3839 lines
106 KiB
C
3839 lines
106 KiB
C
/* vi: set sw=4 ts=4: */
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/*
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* sh.c -- a prototype Bourne shell grammar parser
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* Intended to follow the original Thompson and Ritchie
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* "small and simple is beautiful" philosophy, which
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* incidentally is a good match to today's BusyBox.
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*
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* Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org>
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*
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* Credits:
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* The parser routines proper are all original material, first
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* written Dec 2000 and Jan 2001 by Larry Doolittle. The
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* execution engine, the builtins, and much of the underlying
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* support has been adapted from busybox-0.49pre's lash, which is
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* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
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* written by Erik Andersen <andersen@codepoet.org>. That, in turn,
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* is based in part on ladsh.c, by Michael K. Johnson and Erik W.
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* Troan, which they placed in the public domain. I don't know
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* how much of the Johnson/Troan code has survived the repeated
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* rewrites.
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*
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* Other credits:
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* b_addchr() derived from similar w_addchar function in glibc-2.2
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* setup_redirect(), redirect_opt_num(), and big chunks of main()
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* and many builtins derived from contributions by Erik Andersen
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* miscellaneous bugfixes from Matt Kraai
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*
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* There are two big (and related) architecture differences between
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* this parser and the lash parser. One is that this version is
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* actually designed from the ground up to understand nearly all
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* of the Bourne grammar. The second, consequential change is that
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* the parser and input reader have been turned inside out. Now,
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* the parser is in control, and asks for input as needed. The old
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* way had the input reader in control, and it asked for parsing to
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* take place as needed. The new way makes it much easier to properly
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* handle the recursion implicit in the various substitutions, especially
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* across continuation lines.
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*
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* Bash grammar not implemented: (how many of these were in original sh?)
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* $_
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* ! negation operator for pipes
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* &> and >& redirection of stdout+stderr
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* Brace Expansion
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* Tilde Expansion
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* fancy forms of Parameter Expansion
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* aliases
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* Arithmetic Expansion
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* <(list) and >(list) Process Substitution
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* reserved words: case, esac, select, function
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* Here Documents ( << word )
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* Functions
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* Major bugs:
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* job handling woefully incomplete and buggy (improved --vda)
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* reserved word execution woefully incomplete and buggy
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* to-do:
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* port selected bugfixes from post-0.49 busybox lash - done?
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* finish implementing reserved words: for, while, until, do, done
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* change { and } from special chars to reserved words
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* builtins: break, continue, eval, return, set, trap, ulimit
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* test magic exec
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* handle children going into background
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* clean up recognition of null pipes
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* check setting of global_argc and global_argv
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* control-C handling, probably with longjmp
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* follow IFS rules more precisely, including update semantics
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* figure out what to do with backslash-newline
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* explain why we use signal instead of sigaction
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* propagate syntax errors, die on resource errors?
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* continuation lines, both explicit and implicit - done?
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* memory leak finding and plugging - done?
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* more testing, especially quoting rules and redirection
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* document how quoting rules not precisely followed for variable assignments
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* maybe change charmap[] to use 2-bit entries
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* (eventually) remove all the printf's
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*
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* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
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*/
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#include <glob.h> /* glob, of course */
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#include <getopt.h> /* should be pretty obvious */
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/* #include <dmalloc.h> */
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extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
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#include "busybox.h" /* for struct bb_applet */
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/* If you comment out one of these below, it will be #defined later
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* to perform debug printfs to stderr: */
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#define debug_printf(...) do {} while (0)
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/* Finer-grained debug switches */
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#define debug_printf_parse(...) do {} while (0)
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#define debug_print_tree(a, b) do {} while (0)
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#define debug_printf_exec(...) do {} while (0)
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#define debug_printf_jobs(...) do {} while (0)
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#define debug_printf_expand(...) do {} while (0)
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#define debug_printf_clean(...) do {} while (0)
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#ifndef debug_printf
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#define debug_printf(...) fprintf(stderr, __VA_ARGS__)
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#endif
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#ifndef debug_printf_parse
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#define debug_printf_parse(...) fprintf(stderr, __VA_ARGS__)
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#endif
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#ifndef debug_printf_exec
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#define debug_printf_exec(...) fprintf(stderr, __VA_ARGS__)
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#endif
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#ifndef debug_printf_jobs
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#define debug_printf_jobs(...) fprintf(stderr, __VA_ARGS__)
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#define DEBUG_SHELL_JOBS 1
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#endif
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#ifndef debug_printf_expand
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#define debug_printf_expand(...) fprintf(stderr, __VA_ARGS__)
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#define DEBUG_EXPAND 1
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#endif
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/* Keep unconditionally on for now */
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#define ENABLE_HUSH_DEBUG 1
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#ifndef debug_printf_clean
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/* broken, of course, but OK for testing */
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static const char *indenter(int i)
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{
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static const char blanks[] = " ";
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return &blanks[sizeof(blanks) - i - 1];
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}
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#define debug_printf_clean(...) fprintf(stderr, __VA_ARGS__)
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#define DEBUG_CLEAN 1
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#endif
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#if !ENABLE_HUSH_INTERACTIVE
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#undef ENABLE_FEATURE_EDITING
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#define ENABLE_FEATURE_EDITING 0
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#undef ENABLE_FEATURE_EDITING_FANCY_PROMPT
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#define ENABLE_FEATURE_EDITING_FANCY_PROMPT 0
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#endif
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#define SPECIAL_VAR_SYMBOL 3
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#define PARSEFLAG_EXIT_FROM_LOOP 1
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#define PARSEFLAG_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
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#define PARSEFLAG_REPARSING (1 << 2) /* >= 2nd pass */
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typedef enum {
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REDIRECT_INPUT = 1,
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REDIRECT_OVERWRITE = 2,
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REDIRECT_APPEND = 3,
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REDIRECT_HEREIS = 4,
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REDIRECT_IO = 5
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} redir_type;
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/* The descrip member of this structure is only used to make debugging
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* output pretty */
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static const struct {
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int mode;
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signed char default_fd;
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char descrip[3];
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} redir_table[] = {
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{ 0, 0, "()" },
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{ O_RDONLY, 0, "<" },
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{ O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
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{ O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
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{ O_RDONLY, -1, "<<" },
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{ O_RDWR, 1, "<>" }
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};
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typedef enum {
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PIPE_SEQ = 1,
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PIPE_AND = 2,
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PIPE_OR = 3,
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PIPE_BG = 4,
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} pipe_style;
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/* might eventually control execution */
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typedef enum {
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RES_NONE = 0,
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#if ENABLE_HUSH_IF
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RES_IF = 1,
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RES_THEN = 2,
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RES_ELIF = 3,
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RES_ELSE = 4,
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RES_FI = 5,
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#endif
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#if ENABLE_HUSH_LOOPS
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RES_FOR = 6,
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RES_WHILE = 7,
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RES_UNTIL = 8,
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RES_DO = 9,
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RES_DONE = 10,
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RES_IN = 11,
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#endif
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RES_XXXX = 12,
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RES_SNTX = 13
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} reserved_style;
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enum {
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FLAG_END = (1 << RES_NONE ),
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#if ENABLE_HUSH_IF
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FLAG_IF = (1 << RES_IF ),
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FLAG_THEN = (1 << RES_THEN ),
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FLAG_ELIF = (1 << RES_ELIF ),
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FLAG_ELSE = (1 << RES_ELSE ),
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FLAG_FI = (1 << RES_FI ),
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#endif
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#if ENABLE_HUSH_LOOPS
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FLAG_FOR = (1 << RES_FOR ),
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FLAG_WHILE = (1 << RES_WHILE),
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FLAG_UNTIL = (1 << RES_UNTIL),
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FLAG_DO = (1 << RES_DO ),
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FLAG_DONE = (1 << RES_DONE ),
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FLAG_IN = (1 << RES_IN ),
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#endif
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FLAG_START = (1 << RES_XXXX ),
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};
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/* This holds pointers to the various results of parsing */
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struct p_context {
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struct child_prog *child;
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struct pipe *list_head;
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struct pipe *pipe;
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struct redir_struct *pending_redirect;
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smallint res_w;
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smallint parse_type; /* bitmask of PARSEFLAG_xxx, defines type of parser : ";$" common or special symbol */
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int old_flag; /* bitmask of FLAG_xxx, for figuring out valid reserved words */
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struct p_context *stack;
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/* How about quoting status? */
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};
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struct redir_struct {
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struct redir_struct *next; /* pointer to the next redirect in the list */
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redir_type type; /* type of redirection */
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int fd; /* file descriptor being redirected */
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int dup; /* -1, or file descriptor being duplicated */
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glob_t word; /* *word.gl_pathv is the filename */
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};
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struct child_prog {
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pid_t pid; /* 0 if exited */
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char **argv; /* program name and arguments */
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struct pipe *group; /* if non-NULL, first in group or subshell */
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smallint subshell; /* flag, non-zero if group must be forked */
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smallint is_stopped; /* is the program currently running? */
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struct redir_struct *redirects; /* I/O redirections */
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glob_t glob_result; /* result of parameter globbing */
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struct pipe *family; /* pointer back to the child's parent pipe */
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//sp counting seems to be broken... so commented out, grep for '//sp:'
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//sp: int sp; /* number of SPECIAL_VAR_SYMBOL */
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//seems to be unused, grep for '//pt:'
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//pt: int parse_type;
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};
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/* argv vector may contain variable references (^Cvar^C, ^C0^C etc)
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* and on execution these are substituted with their values.
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* Substitution can make _several_ words out of one argv[n]!
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* Example: argv[0]=='.^C*^C.' here: echo .$*.
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*/
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struct pipe {
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struct pipe *next;
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int num_progs; /* total number of programs in job */
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int running_progs; /* number of programs running (not exited) */
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int stopped_progs; /* number of programs alive, but stopped */
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#if ENABLE_HUSH_JOB
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int jobid; /* job number */
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pid_t pgrp; /* process group ID for the job */
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char *cmdtext; /* name of job */
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#endif
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char *cmdbuf; /* buffer various argv's point into */
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struct child_prog *progs; /* array of commands in pipe */
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int job_context; /* bitmask defining current context */
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smallint followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
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smallint res_word; /* needed for if, for, while, until... */
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};
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struct close_me {
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struct close_me *next;
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int fd;
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};
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/* On program start, environ points to initial environment.
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* putenv adds new pointers into it, unsetenv removes them.
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* Neither of these (de)allocates the strings.
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* setenv allocates new strings in malloc space and does putenv,
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* and thus setenv is unusable (leaky) for shell's purposes */
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#define setenv(...) setenv_is_leaky_dont_use()
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struct variable {
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struct variable *next;
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char *varstr; /* points to "name=" portion */
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int max_len; /* if > 0, name is part of initial env; else name is malloced */
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smallint flg_export; /* putenv should be done on this var */
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smallint flg_read_only;
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};
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typedef struct {
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char *data;
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int length;
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int maxlen;
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int quote;
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int nonnull;
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} o_string;
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#define NULL_O_STRING {NULL,0,0,0,0}
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/* used for initialization: o_string foo = NULL_O_STRING; */
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/* I can almost use ordinary FILE *. Is open_memstream() universally
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* available? Where is it documented? */
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struct in_str {
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const char *p;
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/* eof_flag=1: last char in ->p is really an EOF */
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char eof_flag; /* meaningless if ->p == NULL */
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char peek_buf[2];
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#if ENABLE_HUSH_INTERACTIVE
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smallint promptme;
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smallint promptmode; /* 0: PS1, 1: PS2 */
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#endif
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FILE *file;
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int (*get) (struct in_str *);
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int (*peek) (struct in_str *);
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};
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#define b_getch(input) ((input)->get(input))
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#define b_peek(input) ((input)->peek(input))
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enum {
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CHAR_ORDINARY = 0,
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CHAR_ORDINARY_IF_QUOTED = 1, /* example: *, # */
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CHAR_IFS = 2, /* treated as ordinary if quoted */
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CHAR_SPECIAL = 3, /* example: $ */
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};
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#define HUSH_VER_STR "0.02"
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/* "Globals" within this file */
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/* Sorted roughly by size (smaller offsets == smaller code) */
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struct globals {
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#if ENABLE_HUSH_INTERACTIVE
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/* 'interactive_fd' is a fd# open to ctty, if we have one
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* _AND_ if we decided to act interactively */
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int interactive_fd;
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const char *PS1;
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const char *PS2;
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#endif
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#if ENABLE_FEATURE_EDITING
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line_input_t *line_input_state;
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#endif
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#if ENABLE_HUSH_JOB
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int run_list_level;
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pid_t saved_task_pgrp;
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pid_t saved_tty_pgrp;
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int last_jobid;
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struct pipe *job_list;
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struct pipe *toplevel_list;
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smallint ctrl_z_flag;
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#endif
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smallint fake_mode;
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/* these three support $?, $#, and $1 */
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char **global_argv;
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int global_argc;
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int last_return_code;
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const char *ifs;
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struct close_me *close_me_head;
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const char *cwd;
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unsigned last_bg_pid;
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struct variable *top_var; /* = &shell_ver (set in main()) */
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struct variable shell_ver;
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#if ENABLE_FEATURE_SH_STANDALONE
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struct nofork_save_area nofork_save;
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#endif
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#if ENABLE_HUSH_JOB
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sigjmp_buf toplevel_jb;
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#endif
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unsigned char charmap[256];
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char user_input_buf[ENABLE_FEATURE_EDITING ? BUFSIZ : 2];
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};
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#define G (*ptr_to_globals)
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#if !ENABLE_HUSH_INTERACTIVE
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enum { interactive_fd = 0 };
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#endif
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#if !ENABLE_HUSH_JOB
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enum { run_list_level = 0 };
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#endif
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#if ENABLE_HUSH_INTERACTIVE
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#define interactive_fd (G.interactive_fd )
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#define PS1 (G.PS1 )
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#define PS2 (G.PS2 )
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#endif
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#if ENABLE_FEATURE_EDITING
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#define line_input_state (G.line_input_state)
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#endif
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#if ENABLE_HUSH_JOB
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#define run_list_level (G.run_list_level )
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#define saved_task_pgrp (G.saved_task_pgrp )
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#define saved_tty_pgrp (G.saved_tty_pgrp )
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#define last_jobid (G.last_jobid )
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#define job_list (G.job_list )
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#define toplevel_list (G.toplevel_list )
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#define toplevel_jb (G.toplevel_jb )
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#define ctrl_z_flag (G.ctrl_z_flag )
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#endif /* JOB */
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#define global_argv (G.global_argv )
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#define global_argc (G.global_argc )
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#define last_return_code (G.last_return_code)
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#define ifs (G.ifs )
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#define fake_mode (G.fake_mode )
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#define close_me_head (G.close_me_head )
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#define cwd (G.cwd )
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#define last_bg_pid (G.last_bg_pid )
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#define top_var (G.top_var )
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#define shell_ver (G.shell_ver )
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#if ENABLE_FEATURE_SH_STANDALONE
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#define nofork_save (G.nofork_save )
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#endif
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#if ENABLE_HUSH_JOB
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#define toplevel_jb (G.toplevel_jb )
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#endif
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#define charmap (G.charmap )
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#define user_input_buf (G.user_input_buf )
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#define B_CHUNK 100
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#define B_NOSPAC 1
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#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
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#if 1
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/* Normal */
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static void syntax(const char *msg)
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{
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/* Was using fancy stuff:
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* (interactive_fd ? bb_error_msg : bb_error_msg_and_die)(...params...)
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* but it SEGVs. ?! Oh well... explicit temp ptr works around that */
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void (*fp)(const char *s, ...);
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fp = (interactive_fd ? bb_error_msg : bb_error_msg_and_die);
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fp(msg ? "%s: %s" : "syntax error", "syntax error", msg);
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}
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#else
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/* Debug */
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static void syntax_lineno(int line)
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{
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void (*fp)(const char *s, ...);
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fp = (interactive_fd ? bb_error_msg : bb_error_msg_and_die);
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fp("syntax error hush.c:%d", line);
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}
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#define syntax(str) syntax_lineno(__LINE__)
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#endif
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/* Index of subroutines: */
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/* function prototypes for builtins */
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static int builtin_cd(char **argv);
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static int builtin_eval(char **argv);
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static int builtin_exec(char **argv);
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static int builtin_exit(char **argv);
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static int builtin_export(char **argv);
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#if ENABLE_HUSH_JOB
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static int builtin_fg_bg(char **argv);
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static int builtin_jobs(char **argv);
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#endif
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#if ENABLE_HUSH_HELP
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static int builtin_help(char **argv);
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#endif
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static int builtin_pwd(char **argv);
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static int builtin_read(char **argv);
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static int builtin_set(char **argv);
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static int builtin_shift(char **argv);
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static int builtin_source(char **argv);
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static int builtin_umask(char **argv);
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static int builtin_unset(char **argv);
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//static int builtin_not_written(char **argv);
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/* o_string manipulation: */
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static int b_check_space(o_string *o, int len);
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|
static int b_addchr(o_string *o, int ch);
|
|
static void b_reset(o_string *o);
|
|
static int b_addqchr(o_string *o, int ch, int quote);
|
|
/* in_str manipulations: */
|
|
static int static_get(struct in_str *i);
|
|
static int static_peek(struct in_str *i);
|
|
static int file_get(struct in_str *i);
|
|
static int file_peek(struct in_str *i);
|
|
static void setup_file_in_str(struct in_str *i, FILE *f);
|
|
static void setup_string_in_str(struct in_str *i, const char *s);
|
|
/* close_me manipulations: */
|
|
static void mark_open(int fd);
|
|
static void mark_closed(int fd);
|
|
static void close_all(void);
|
|
/* "run" the final data structures: */
|
|
#if !defined(DEBUG_CLEAN)
|
|
#define free_pipe_list(head, indent) free_pipe_list(head)
|
|
#define free_pipe(pi, indent) free_pipe(pi)
|
|
#endif
|
|
static int free_pipe_list(struct pipe *head, int indent);
|
|
static int free_pipe(struct pipe *pi, int indent);
|
|
/* really run the final data structures: */
|
|
static int setup_redirects(struct child_prog *prog, int squirrel[]);
|
|
static int run_list_real(struct pipe *pi);
|
|
static void pseudo_exec_argv(char **argv) ATTRIBUTE_NORETURN;
|
|
static void pseudo_exec(struct child_prog *child) ATTRIBUTE_NORETURN;
|
|
static int run_pipe_real(struct pipe *pi);
|
|
/* extended glob support: */
|
|
static int globhack(const char *src, int flags, glob_t *pglob);
|
|
static int glob_needed(const char *s);
|
|
static int xglob(o_string *dest, int flags, glob_t *pglob);
|
|
/* variable assignment: */
|
|
static int is_assignment(const char *s);
|
|
/* data structure manipulation: */
|
|
static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input);
|
|
static void initialize_context(struct p_context *ctx);
|
|
static int done_word(o_string *dest, struct p_context *ctx);
|
|
static int done_command(struct p_context *ctx);
|
|
static int done_pipe(struct p_context *ctx, pipe_style type);
|
|
/* primary string parsing: */
|
|
static int redirect_dup_num(struct in_str *input);
|
|
static int redirect_opt_num(o_string *o);
|
|
#if ENABLE_HUSH_TICK
|
|
static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, const char *subst_end);
|
|
#endif
|
|
static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch);
|
|
static const char *lookup_param(const char *src);
|
|
static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input);
|
|
static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, const char *end_trigger);
|
|
/* setup: */
|
|
static int parse_and_run_stream(struct in_str *inp, int parse_flag);
|
|
static int parse_and_run_string(const char *s, int parse_flag);
|
|
static int parse_and_run_file(FILE *f);
|
|
/* job management: */
|
|
static int checkjobs(struct pipe* fg_pipe);
|
|
#if ENABLE_HUSH_JOB
|
|
static int checkjobs_and_fg_shell(struct pipe* fg_pipe);
|
|
static void insert_bg_job(struct pipe *pi);
|
|
static void remove_bg_job(struct pipe *pi);
|
|
static void delete_finished_bg_job(struct pipe *pi);
|
|
#else
|
|
int checkjobs_and_fg_shell(struct pipe* fg_pipe); /* never called */
|
|
#endif
|
|
/* local variable support */
|
|
static char **expand_strvec_to_strvec(char **argv);
|
|
/* used for eval */
|
|
static char *expand_strvec_to_string(char **argv);
|
|
/* used for expansion of right hand of assignments */
|
|
static char *expand_string_to_string(const char *str);
|
|
static struct variable *get_local_var(const char *name);
|
|
static int set_local_var(char *str, int flg_export);
|
|
static void unset_local_var(const char *name);
|
|
|
|
/* Table of built-in functions. They can be forked or not, depending on
|
|
* context: within pipes, they fork. As simple commands, they do not.
|
|
* When used in non-forking context, they can change global variables
|
|
* in the parent shell process. If forked, of course they cannot.
|
|
* For example, 'unset foo | whatever' will parse and run, but foo will
|
|
* still be set at the end. */
|
|
struct built_in_command {
|
|
const char *cmd; /* name */
|
|
int (*function) (char **argv); /* function ptr */
|
|
#if ENABLE_HUSH_HELP
|
|
const char *descr; /* description */
|
|
#define BLTIN(cmd, func, help) { cmd, func, help }
|
|
#else
|
|
#define BLTIN(cmd, func, help) { cmd, func }
|
|
#endif
|
|
};
|
|
|
|
static const struct built_in_command bltins[] = {
|
|
#if ENABLE_HUSH_JOB
|
|
BLTIN("bg" , builtin_fg_bg, "Resume a job in the background"),
|
|
#endif
|
|
// BLTIN("break" , builtin_not_written, "Exit for, while or until loop"),
|
|
BLTIN("cd" , builtin_cd, "Change working directory"),
|
|
// BLTIN("continue", builtin_not_written, "Continue for, while or until loop"),
|
|
BLTIN("eval" , builtin_eval, "Construct and run shell command"),
|
|
BLTIN("exec" , builtin_exec, "Exec command, replacing this shell with the exec'd process"),
|
|
BLTIN("exit" , builtin_exit, "Exit from shell"),
|
|
BLTIN("export", builtin_export, "Set environment variable"),
|
|
#if ENABLE_HUSH_JOB
|
|
BLTIN("fg" , builtin_fg_bg, "Bring job into the foreground"),
|
|
BLTIN("jobs" , builtin_jobs, "Lists the active jobs"),
|
|
#endif
|
|
// TODO: remove pwd? we have it as an applet...
|
|
BLTIN("pwd" , builtin_pwd, "Print current directory"),
|
|
BLTIN("read" , builtin_read, "Input environment variable"),
|
|
// BLTIN("return", builtin_not_written, "Return from a function"),
|
|
BLTIN("set" , builtin_set, "Set/unset shell local variables"),
|
|
BLTIN("shift" , builtin_shift, "Shift positional parameters"),
|
|
// BLTIN("trap" , builtin_not_written, "Trap signals"),
|
|
// BLTIN("ulimit", builtin_not_written, "Controls resource limits"),
|
|
BLTIN("umask" , builtin_umask, "Sets file creation mask"),
|
|
BLTIN("unset" , builtin_unset, "Unset environment variable"),
|
|
BLTIN("." , builtin_source, "Source-in and run commands in a file"),
|
|
#if ENABLE_HUSH_HELP
|
|
BLTIN("help" , builtin_help, "List shell built-in commands"),
|
|
#endif
|
|
BLTIN(NULL, NULL, NULL)
|
|
};
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
|
|
/* move to libbb? */
|
|
static void signal_SA_RESTART(int sig, void (*handler)(int))
|
|
{
|
|
struct sigaction sa;
|
|
sa.sa_handler = handler;
|
|
sa.sa_flags = SA_RESTART;
|
|
sigemptyset(&sa.sa_mask);
|
|
sigaction(sig, &sa, NULL);
|
|
}
|
|
|
|
/* Signals are grouped, we handle them in batches */
|
|
static void set_fatal_sighandler(void (*handler)(int))
|
|
{
|
|
signal(SIGILL , handler);
|
|
signal(SIGTRAP, handler);
|
|
signal(SIGABRT, handler);
|
|
signal(SIGFPE , handler);
|
|
signal(SIGBUS , handler);
|
|
signal(SIGSEGV, handler);
|
|
/* bash 3.2 seems to handle these just like 'fatal' ones */
|
|
signal(SIGHUP , handler);
|
|
signal(SIGPIPE, handler);
|
|
signal(SIGALRM, handler);
|
|
}
|
|
static void set_jobctrl_sighandler(void (*handler)(int))
|
|
{
|
|
signal(SIGTSTP, handler);
|
|
signal(SIGTTIN, handler);
|
|
signal(SIGTTOU, handler);
|
|
}
|
|
static void set_misc_sighandler(void (*handler)(int))
|
|
{
|
|
signal(SIGINT , handler);
|
|
signal(SIGQUIT, handler);
|
|
signal(SIGTERM, handler);
|
|
}
|
|
/* SIGCHLD is special and handled separately */
|
|
|
|
static void set_every_sighandler(void (*handler)(int))
|
|
{
|
|
set_fatal_sighandler(handler);
|
|
set_jobctrl_sighandler(handler);
|
|
set_misc_sighandler(handler);
|
|
signal(SIGCHLD, handler);
|
|
}
|
|
|
|
static void handler_ctrl_c(int sig)
|
|
{
|
|
debug_printf_jobs("got sig %d\n", sig);
|
|
// as usual we can have all kinds of nasty problems with leaked malloc data here
|
|
siglongjmp(toplevel_jb, 1);
|
|
}
|
|
|
|
static void handler_ctrl_z(int sig)
|
|
{
|
|
pid_t pid;
|
|
|
|
debug_printf_jobs("got tty sig %d in pid %d\n", sig, getpid());
|
|
pid = fork();
|
|
if (pid < 0) /* can't fork. Pretend there was no ctrl-Z */
|
|
return;
|
|
ctrl_z_flag = 1;
|
|
if (!pid) { /* child */
|
|
setpgrp();
|
|
debug_printf_jobs("set pgrp for child %d ok\n", getpid());
|
|
set_every_sighandler(SIG_DFL);
|
|
raise(SIGTSTP); /* resend TSTP so that child will be stopped */
|
|
debug_printf_jobs("returning in child\n");
|
|
/* return to nofork, it will eventually exit now,
|
|
* not return back to shell */
|
|
return;
|
|
}
|
|
/* parent */
|
|
/* finish filling up pipe info */
|
|
toplevel_list->pgrp = pid; /* child is in its own pgrp */
|
|
toplevel_list->progs[0].pid = pid;
|
|
/* parent needs to longjmp out of running nofork.
|
|
* we will "return" exitcode 0, with child put in background */
|
|
// as usual we can have all kinds of nasty problems with leaked malloc data here
|
|
debug_printf_jobs("siglongjmp in parent\n");
|
|
siglongjmp(toplevel_jb, 1);
|
|
}
|
|
|
|
/* Restores tty foreground process group, and exits.
|
|
* May be called as signal handler for fatal signal
|
|
* (will faithfully resend signal to itself, producing correct exit state)
|
|
* or called directly with -EXITCODE.
|
|
* We also call it if xfunc is exiting. */
|
|
static void sigexit(int sig) ATTRIBUTE_NORETURN;
|
|
static void sigexit(int sig)
|
|
{
|
|
sigset_t block_all;
|
|
|
|
/* Disable all signals: job control, SIGPIPE, etc. */
|
|
sigfillset(&block_all);
|
|
sigprocmask(SIG_SETMASK, &block_all, NULL);
|
|
|
|
if (interactive_fd)
|
|
tcsetpgrp(interactive_fd, saved_tty_pgrp);
|
|
|
|
/* Not a signal, just exit */
|
|
if (sig <= 0)
|
|
_exit(- sig);
|
|
|
|
/* Enable only this sig and kill ourself with it */
|
|
signal(sig, SIG_DFL);
|
|
sigdelset(&block_all, sig);
|
|
sigprocmask(SIG_SETMASK, &block_all, NULL);
|
|
raise(sig);
|
|
_exit(1); /* Should not reach it */
|
|
}
|
|
|
|
/* Restores tty foreground process group, and exits. */
|
|
static void hush_exit(int exitcode) ATTRIBUTE_NORETURN;
|
|
static void hush_exit(int exitcode)
|
|
{
|
|
fflush(NULL); /* flush all streams */
|
|
sigexit(- (exitcode & 0xff));
|
|
}
|
|
|
|
#else /* !JOB */
|
|
|
|
#define set_fatal_sighandler(handler) ((void)0)
|
|
#define set_jobctrl_sighandler(handler) ((void)0)
|
|
#define set_misc_sighandler(handler) ((void)0)
|
|
#define hush_exit(e) exit(e)
|
|
|
|
#endif /* JOB */
|
|
|
|
|
|
static const char *set_cwd(void)
|
|
{
|
|
if (cwd == bb_msg_unknown)
|
|
cwd = NULL; /* xrealloc_getcwd_or_warn(arg) calls free(arg)! */
|
|
cwd = xrealloc_getcwd_or_warn((char *)cwd);
|
|
if (!cwd)
|
|
cwd = bb_msg_unknown;
|
|
return cwd;
|
|
}
|
|
|
|
/* built-in 'eval' handler */
|
|
static int builtin_eval(char **argv)
|
|
{
|
|
int rcode = EXIT_SUCCESS;
|
|
|
|
if (argv[1]) {
|
|
char *str = expand_strvec_to_string(argv + 1);
|
|
parse_and_run_string(str, PARSEFLAG_EXIT_FROM_LOOP |
|
|
PARSEFLAG_SEMICOLON);
|
|
free(str);
|
|
rcode = last_return_code;
|
|
}
|
|
return rcode;
|
|
}
|
|
|
|
/* built-in 'cd <path>' handler */
|
|
static int builtin_cd(char **argv)
|
|
{
|
|
const char *newdir;
|
|
if (argv[1] == NULL)
|
|
newdir = getenv("HOME") ? : "/";
|
|
else
|
|
newdir = argv[1];
|
|
if (chdir(newdir)) {
|
|
printf("cd: %s: %s\n", newdir, strerror(errno));
|
|
return EXIT_FAILURE;
|
|
}
|
|
set_cwd();
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|
|
/* built-in 'exec' handler */
|
|
static int builtin_exec(char **argv)
|
|
{
|
|
if (argv[1] == NULL)
|
|
return EXIT_SUCCESS; /* Really? */
|
|
pseudo_exec_argv(argv + 1);
|
|
/* never returns */
|
|
}
|
|
|
|
/* built-in 'exit' handler */
|
|
static int builtin_exit(char **argv)
|
|
{
|
|
// TODO: bash does it ONLY on top-level sh exit (+interacive only?)
|
|
//puts("exit"); /* bash does it */
|
|
// TODO: warn if we have background jobs: "There are stopped jobs"
|
|
// On second consecutive 'exit', exit anyway.
|
|
|
|
if (argv[1] == NULL)
|
|
hush_exit(last_return_code);
|
|
/* mimic bash: exit 123abc == exit 255 + error msg */
|
|
xfunc_error_retval = 255;
|
|
/* bash: exit -2 == exit 254, no error msg */
|
|
hush_exit(xatoi(argv[1]) & 0xff);
|
|
}
|
|
|
|
/* built-in 'export VAR=value' handler */
|
|
static int builtin_export(char **argv)
|
|
{
|
|
const char *value;
|
|
char *name = argv[1];
|
|
|
|
if (name == NULL) {
|
|
// TODO:
|
|
// ash emits: export VAR='VAL'
|
|
// bash: declare -x VAR="VAL"
|
|
// (both also escape as needed (quotes, $, etc))
|
|
char **e = environ;
|
|
if (e)
|
|
while (*e)
|
|
puts(*e++);
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|
|
value = strchr(name, '=');
|
|
if (!value) {
|
|
/* They are exporting something without a =VALUE */
|
|
struct variable *var;
|
|
|
|
var = get_local_var(name);
|
|
if (var) {
|
|
var->flg_export = 1;
|
|
putenv(var->varstr);
|
|
}
|
|
/* bash does not return an error when trying to export
|
|
* an undefined variable. Do likewise. */
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|
|
set_local_var(xstrdup(name), 1);
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
/* built-in 'fg' and 'bg' handler */
|
|
static int builtin_fg_bg(char **argv)
|
|
{
|
|
int i, jobnum;
|
|
struct pipe *pi;
|
|
|
|
if (!interactive_fd)
|
|
return EXIT_FAILURE;
|
|
/* If they gave us no args, assume they want the last backgrounded task */
|
|
if (!argv[1]) {
|
|
for (pi = job_list; pi; pi = pi->next) {
|
|
if (pi->jobid == last_jobid) {
|
|
goto found;
|
|
}
|
|
}
|
|
bb_error_msg("%s: no current job", argv[0]);
|
|
return EXIT_FAILURE;
|
|
}
|
|
if (sscanf(argv[1], "%%%d", &jobnum) != 1) {
|
|
bb_error_msg("%s: bad argument '%s'", argv[0], argv[1]);
|
|
return EXIT_FAILURE;
|
|
}
|
|
for (pi = job_list; pi; pi = pi->next) {
|
|
if (pi->jobid == jobnum) {
|
|
goto found;
|
|
}
|
|
}
|
|
bb_error_msg("%s: %d: no such job", argv[0], jobnum);
|
|
return EXIT_FAILURE;
|
|
found:
|
|
// TODO: bash prints a string representation
|
|
// of job being foregrounded (like "sleep 1 | cat")
|
|
if (*argv[0] == 'f') {
|
|
/* Put the job into the foreground. */
|
|
tcsetpgrp(interactive_fd, pi->pgrp);
|
|
}
|
|
|
|
/* Restart the processes in the job */
|
|
debug_printf_jobs("reviving %d procs, pgrp %d\n", pi->num_progs, pi->pgrp);
|
|
for (i = 0; i < pi->num_progs; i++) {
|
|
debug_printf_jobs("reviving pid %d\n", pi->progs[i].pid);
|
|
pi->progs[i].is_stopped = 0;
|
|
}
|
|
pi->stopped_progs = 0;
|
|
|
|
i = kill(- pi->pgrp, SIGCONT);
|
|
if (i < 0) {
|
|
if (errno == ESRCH) {
|
|
delete_finished_bg_job(pi);
|
|
return EXIT_SUCCESS;
|
|
} else {
|
|
bb_perror_msg("kill (SIGCONT)");
|
|
}
|
|
}
|
|
|
|
if (*argv[0] == 'f') {
|
|
remove_bg_job(pi);
|
|
return checkjobs_and_fg_shell(pi);
|
|
}
|
|
return EXIT_SUCCESS;
|
|
}
|
|
#endif
|
|
|
|
/* built-in 'help' handler */
|
|
#if ENABLE_HUSH_HELP
|
|
static int builtin_help(char **argv ATTRIBUTE_UNUSED)
|
|
{
|
|
const struct built_in_command *x;
|
|
|
|
printf("\nBuilt-in commands:\n");
|
|
printf("-------------------\n");
|
|
for (x = bltins; x->cmd; x++) {
|
|
printf("%s\t%s\n", x->cmd, x->descr);
|
|
}
|
|
printf("\n\n");
|
|
return EXIT_SUCCESS;
|
|
}
|
|
#endif
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
/* built-in 'jobs' handler */
|
|
static int builtin_jobs(char **argv ATTRIBUTE_UNUSED)
|
|
{
|
|
struct pipe *job;
|
|
const char *status_string;
|
|
|
|
for (job = job_list; job; job = job->next) {
|
|
if (job->running_progs == job->stopped_progs)
|
|
status_string = "Stopped";
|
|
else
|
|
status_string = "Running";
|
|
|
|
printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->cmdtext);
|
|
}
|
|
return EXIT_SUCCESS;
|
|
}
|
|
#endif
|
|
|
|
/* built-in 'pwd' handler */
|
|
static int builtin_pwd(char **argv ATTRIBUTE_UNUSED)
|
|
{
|
|
puts(set_cwd());
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|
|
/* built-in 'read VAR' handler */
|
|
static int builtin_read(char **argv)
|
|
{
|
|
char *string;
|
|
const char *name = argv[1] ? argv[1] : "REPLY";
|
|
|
|
string = xmalloc_reads(STDIN_FILENO, xasprintf("%s=", name));
|
|
return set_local_var(string, 0);
|
|
}
|
|
|
|
/* built-in 'set [VAR=value]' handler */
|
|
static int builtin_set(char **argv)
|
|
{
|
|
char *temp = argv[1];
|
|
struct variable *e;
|
|
|
|
if (temp == NULL)
|
|
for (e = top_var; e; e = e->next)
|
|
puts(e->varstr);
|
|
else
|
|
set_local_var(xstrdup(temp), 0);
|
|
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|
|
|
|
/* Built-in 'shift' handler */
|
|
static int builtin_shift(char **argv)
|
|
{
|
|
int n = 1;
|
|
if (argv[1]) {
|
|
n = atoi(argv[1]);
|
|
}
|
|
if (n >= 0 && n < global_argc) {
|
|
global_argv[n] = global_argv[0];
|
|
global_argc -= n;
|
|
global_argv += n;
|
|
return EXIT_SUCCESS;
|
|
}
|
|
return EXIT_FAILURE;
|
|
}
|
|
|
|
/* Built-in '.' handler (read-in and execute commands from file) */
|
|
static int builtin_source(char **argv)
|
|
{
|
|
FILE *input;
|
|
int status;
|
|
|
|
if (argv[1] == NULL)
|
|
return EXIT_FAILURE;
|
|
|
|
/* XXX search through $PATH is missing */
|
|
input = fopen(argv[1], "r");
|
|
if (!input) {
|
|
bb_error_msg("cannot open '%s'", argv[1]);
|
|
return EXIT_FAILURE;
|
|
}
|
|
|
|
/* Now run the file */
|
|
/* XXX argv and argc are broken; need to save old global_argv
|
|
* (pointer only is OK!) on this stack frame,
|
|
* set global_argv=argv+1, recurse, and restore. */
|
|
mark_open(fileno(input));
|
|
status = parse_and_run_file(input);
|
|
mark_closed(fileno(input));
|
|
fclose(input);
|
|
return status;
|
|
}
|
|
|
|
static int builtin_umask(char **argv)
|
|
{
|
|
mode_t new_umask;
|
|
const char *arg = argv[1];
|
|
char *end;
|
|
if (arg) {
|
|
new_umask = strtoul(arg, &end, 8);
|
|
if (*end != '\0' || end == arg) {
|
|
return EXIT_FAILURE;
|
|
}
|
|
} else {
|
|
new_umask = umask(0);
|
|
printf("%.3o\n", (unsigned) new_umask);
|
|
}
|
|
umask(new_umask);
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|
|
/* built-in 'unset VAR' handler */
|
|
static int builtin_unset(char **argv)
|
|
{
|
|
/* bash always returns true */
|
|
unset_local_var(argv[1]);
|
|
return EXIT_SUCCESS;
|
|
}
|
|
|
|
//static int builtin_not_written(char **argv)
|
|
//{
|
|
// printf("builtin_%s not written\n", argv[0]);
|
|
// return EXIT_FAILURE;
|
|
//}
|
|
|
|
static int b_check_space(o_string *o, int len)
|
|
{
|
|
/* It would be easy to drop a more restrictive policy
|
|
* in here, such as setting a maximum string length */
|
|
if (o->length + len > o->maxlen) {
|
|
/* assert(data == NULL || o->maxlen != 0); */
|
|
o->maxlen += (2*len > B_CHUNK ? 2*len : B_CHUNK);
|
|
o->data = xrealloc(o->data, 1 + o->maxlen);
|
|
}
|
|
return o->data == NULL;
|
|
}
|
|
|
|
static int b_addchr(o_string *o, int ch)
|
|
{
|
|
debug_printf("b_addchr: '%c' o->length=%d o=%p\n", ch, o->length, o);
|
|
if (b_check_space(o, 1))
|
|
return B_NOSPAC;
|
|
o->data[o->length] = ch;
|
|
o->length++;
|
|
o->data[o->length] = '\0';
|
|
return 0;
|
|
}
|
|
|
|
static void b_reset(o_string *o)
|
|
{
|
|
o->length = 0;
|
|
o->nonnull = 0;
|
|
if (o->data != NULL)
|
|
*o->data = '\0';
|
|
}
|
|
|
|
static void b_free(o_string *o)
|
|
{
|
|
b_reset(o);
|
|
free(o->data);
|
|
o->data = NULL;
|
|
o->maxlen = 0;
|
|
}
|
|
|
|
/* My analysis of quoting semantics tells me that state information
|
|
* is associated with a destination, not a source.
|
|
*/
|
|
static int b_addqchr(o_string *o, int ch, int quote)
|
|
{
|
|
if (quote && strchr("*?[\\", ch)) {
|
|
int rc;
|
|
rc = b_addchr(o, '\\');
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
return b_addchr(o, ch);
|
|
}
|
|
|
|
static int static_get(struct in_str *i)
|
|
{
|
|
int ch = *i->p++;
|
|
if (ch == '\0') return EOF;
|
|
return ch;
|
|
}
|
|
|
|
static int static_peek(struct in_str *i)
|
|
{
|
|
return *i->p;
|
|
}
|
|
|
|
#if ENABLE_HUSH_INTERACTIVE
|
|
#if ENABLE_FEATURE_EDITING
|
|
static void cmdedit_set_initial_prompt(void)
|
|
{
|
|
#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
|
|
PS1 = NULL;
|
|
#else
|
|
PS1 = getenv("PS1");
|
|
if (PS1 == NULL)
|
|
PS1 = "\\w \\$ ";
|
|
#endif
|
|
}
|
|
#endif /* EDITING */
|
|
|
|
static const char* setup_prompt_string(int promptmode)
|
|
{
|
|
const char *prompt_str;
|
|
debug_printf("setup_prompt_string %d ", promptmode);
|
|
#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
|
|
/* Set up the prompt */
|
|
if (promptmode == 0) { /* PS1 */
|
|
free((char*)PS1);
|
|
PS1 = xasprintf("%s %c ", cwd, (geteuid() != 0) ? '$' : '#');
|
|
prompt_str = PS1;
|
|
} else {
|
|
prompt_str = PS2;
|
|
}
|
|
#else
|
|
prompt_str = (promptmode == 0) ? PS1 : PS2;
|
|
#endif
|
|
debug_printf("result '%s'\n", prompt_str);
|
|
return prompt_str;
|
|
}
|
|
|
|
static void get_user_input(struct in_str *i)
|
|
{
|
|
int r;
|
|
const char *prompt_str;
|
|
|
|
prompt_str = setup_prompt_string(i->promptmode);
|
|
#if ENABLE_FEATURE_EDITING
|
|
/* Enable command line editing only while a command line
|
|
* is actually being read; otherwise, we'll end up bequeathing
|
|
* atexit() handlers and other unwanted stuff to our
|
|
* child processes (rob@sysgo.de) */
|
|
r = read_line_input(prompt_str, user_input_buf, BUFSIZ-1, line_input_state);
|
|
i->eof_flag = (r < 0);
|
|
if (i->eof_flag) { /* EOF/error detected */
|
|
user_input_buf[0] = EOF; /* yes, it will be truncated, it's ok */
|
|
user_input_buf[1] = '\0';
|
|
}
|
|
#else
|
|
fputs(prompt_str, stdout);
|
|
fflush(stdout);
|
|
user_input_buf[0] = r = fgetc(i->file);
|
|
/*user_input_buf[1] = '\0'; - already is and never changed */
|
|
i->eof_flag = (r == EOF);
|
|
#endif
|
|
i->p = user_input_buf;
|
|
}
|
|
#endif /* INTERACTIVE */
|
|
|
|
/* This is the magic location that prints prompts
|
|
* and gets data back from the user */
|
|
static int file_get(struct in_str *i)
|
|
{
|
|
int ch;
|
|
|
|
/* If there is data waiting, eat it up */
|
|
if (i->p && *i->p) {
|
|
#if ENABLE_HUSH_INTERACTIVE
|
|
take_cached:
|
|
#endif
|
|
ch = *i->p++;
|
|
if (i->eof_flag && !*i->p)
|
|
ch = EOF;
|
|
} else {
|
|
/* need to double check i->file because we might be doing something
|
|
* more complicated by now, like sourcing or substituting. */
|
|
#if ENABLE_HUSH_INTERACTIVE
|
|
if (interactive_fd && i->promptme && i->file == stdin) {
|
|
do {
|
|
get_user_input(i);
|
|
} while (!*i->p); /* need non-empty line */
|
|
i->promptmode = 1; /* PS2 */
|
|
i->promptme = 0;
|
|
goto take_cached;
|
|
}
|
|
#endif
|
|
ch = fgetc(i->file);
|
|
}
|
|
debug_printf("file_get: got a '%c' %d\n", ch, ch);
|
|
#if ENABLE_HUSH_INTERACTIVE
|
|
if (ch == '\n')
|
|
i->promptme = 1;
|
|
#endif
|
|
return ch;
|
|
}
|
|
|
|
/* All the callers guarantee this routine will never be
|
|
* used right after a newline, so prompting is not needed.
|
|
*/
|
|
static int file_peek(struct in_str *i)
|
|
{
|
|
int ch;
|
|
if (i->p && *i->p) {
|
|
if (i->eof_flag && !i->p[1])
|
|
return EOF;
|
|
return *i->p;
|
|
}
|
|
ch = fgetc(i->file);
|
|
i->eof_flag = (ch == EOF);
|
|
i->peek_buf[0] = ch;
|
|
i->peek_buf[1] = '\0';
|
|
i->p = i->peek_buf;
|
|
debug_printf("file_peek: got a '%c' %d\n", *i->p, *i->p);
|
|
return ch;
|
|
}
|
|
|
|
static void setup_file_in_str(struct in_str *i, FILE *f)
|
|
{
|
|
i->peek = file_peek;
|
|
i->get = file_get;
|
|
#if ENABLE_HUSH_INTERACTIVE
|
|
i->promptme = 1;
|
|
i->promptmode = 0; /* PS1 */
|
|
#endif
|
|
i->file = f;
|
|
i->p = NULL;
|
|
}
|
|
|
|
static void setup_string_in_str(struct in_str *i, const char *s)
|
|
{
|
|
i->peek = static_peek;
|
|
i->get = static_get;
|
|
#if ENABLE_HUSH_INTERACTIVE
|
|
i->promptme = 1;
|
|
i->promptmode = 0; /* PS1 */
|
|
#endif
|
|
i->p = s;
|
|
i->eof_flag = 0;
|
|
}
|
|
|
|
static void mark_open(int fd)
|
|
{
|
|
struct close_me *new = xmalloc(sizeof(struct close_me));
|
|
new->fd = fd;
|
|
new->next = close_me_head;
|
|
close_me_head = new;
|
|
}
|
|
|
|
static void mark_closed(int fd)
|
|
{
|
|
struct close_me *tmp;
|
|
if (close_me_head == NULL || close_me_head->fd != fd)
|
|
bb_error_msg_and_die("corrupt close_me");
|
|
tmp = close_me_head;
|
|
close_me_head = close_me_head->next;
|
|
free(tmp);
|
|
}
|
|
|
|
static void close_all(void)
|
|
{
|
|
struct close_me *c;
|
|
for (c = close_me_head; c; c = c->next) {
|
|
close(c->fd);
|
|
}
|
|
close_me_head = NULL;
|
|
}
|
|
|
|
/* squirrel != NULL means we squirrel away copies of stdin, stdout,
|
|
* and stderr if they are redirected. */
|
|
static int setup_redirects(struct child_prog *prog, int squirrel[])
|
|
{
|
|
int openfd, mode;
|
|
struct redir_struct *redir;
|
|
|
|
for (redir = prog->redirects; redir; redir = redir->next) {
|
|
if (redir->dup == -1 && redir->word.gl_pathv == NULL) {
|
|
/* something went wrong in the parse. Pretend it didn't happen */
|
|
continue;
|
|
}
|
|
if (redir->dup == -1) {
|
|
mode = redir_table[redir->type].mode;
|
|
openfd = open_or_warn(redir->word.gl_pathv[0], mode);
|
|
if (openfd < 0) {
|
|
/* this could get lost if stderr has been redirected, but
|
|
bash and ash both lose it as well (though zsh doesn't!) */
|
|
return 1;
|
|
}
|
|
} else {
|
|
openfd = redir->dup;
|
|
}
|
|
|
|
if (openfd != redir->fd) {
|
|
if (squirrel && redir->fd < 3) {
|
|
squirrel[redir->fd] = dup(redir->fd);
|
|
}
|
|
if (openfd == -3) {
|
|
close(openfd);
|
|
} else {
|
|
dup2(openfd, redir->fd);
|
|
if (redir->dup == -1)
|
|
close(openfd);
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static void restore_redirects(int squirrel[])
|
|
{
|
|
int i, fd;
|
|
for (i = 0; i < 3; i++) {
|
|
fd = squirrel[i];
|
|
if (fd != -1) {
|
|
/* We simply die on error */
|
|
xmove_fd(fd, i);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* never returns */
|
|
/* XXX no exit() here. If you don't exec, use _exit instead.
|
|
* The at_exit handlers apparently confuse the calling process,
|
|
* in particular stdin handling. Not sure why? -- because of vfork! (vda) */
|
|
static void pseudo_exec_argv(char **argv)
|
|
{
|
|
int i, rcode;
|
|
char *p;
|
|
const struct built_in_command *x;
|
|
|
|
for (i = 0; is_assignment(argv[i]); i++) {
|
|
debug_printf_exec("pid %d environment modification: %s\n",
|
|
getpid(), argv[i]);
|
|
// FIXME: vfork case??
|
|
p = expand_string_to_string(argv[i]);
|
|
putenv(p);
|
|
}
|
|
argv += i;
|
|
/* If a variable is assigned in a forest, and nobody listens,
|
|
* was it ever really set?
|
|
*/
|
|
if (argv[0] == NULL) {
|
|
_exit(EXIT_SUCCESS);
|
|
}
|
|
|
|
argv = expand_strvec_to_strvec(argv);
|
|
|
|
/*
|
|
* Check if the command matches any of the builtins.
|
|
* Depending on context, this might be redundant. But it's
|
|
* easier to waste a few CPU cycles than it is to figure out
|
|
* if this is one of those cases.
|
|
*/
|
|
for (x = bltins; x->cmd; x++) {
|
|
if (strcmp(argv[0], x->cmd) == 0) {
|
|
debug_printf_exec("running builtin '%s'\n", argv[0]);
|
|
rcode = x->function(argv);
|
|
fflush(stdout);
|
|
_exit(rcode);
|
|
}
|
|
}
|
|
|
|
/* Check if the command matches any busybox applets */
|
|
#if ENABLE_FEATURE_SH_STANDALONE
|
|
if (strchr(argv[0], '/') == NULL) {
|
|
const struct bb_applet *a = find_applet_by_name(argv[0]);
|
|
if (a) {
|
|
if (a->noexec) {
|
|
current_applet = a;
|
|
debug_printf_exec("running applet '%s'\n", argv[0]);
|
|
// is it ok that run_current_applet_and_exit() does exit(), not _exit()?
|
|
run_current_applet_and_exit(argv);
|
|
}
|
|
/* re-exec ourselves with the new arguments */
|
|
debug_printf_exec("re-execing applet '%s'\n", argv[0]);
|
|
execvp(bb_busybox_exec_path, argv);
|
|
/* If they called chroot or otherwise made the binary no longer
|
|
* executable, fall through */
|
|
}
|
|
}
|
|
#endif
|
|
|
|
debug_printf_exec("execing '%s'\n", argv[0]);
|
|
execvp(argv[0], argv);
|
|
bb_perror_msg("cannot exec '%s'", argv[0]);
|
|
_exit(1);
|
|
}
|
|
|
|
static void pseudo_exec(struct child_prog *child)
|
|
{
|
|
// FIXME: buggy wrt NOMMU! Must not modify any global data
|
|
// until it does exec/_exit, but currently it does.
|
|
int rcode;
|
|
|
|
if (child->argv) {
|
|
pseudo_exec_argv(child->argv);
|
|
}
|
|
|
|
if (child->group) {
|
|
// FIXME: do not modify globals! Think vfork!
|
|
#if ENABLE_HUSH_INTERACTIVE
|
|
debug_printf_exec("pseudo_exec: setting interactive_fd=0\n");
|
|
interactive_fd = 0; /* crucial!!!! */
|
|
#endif
|
|
debug_printf_exec("pseudo_exec: run_list_real\n");
|
|
rcode = run_list_real(child->group);
|
|
/* OK to leak memory by not calling free_pipe_list,
|
|
* since this process is about to exit */
|
|
_exit(rcode);
|
|
}
|
|
|
|
/* Can happen. See what bash does with ">foo" by itself. */
|
|
debug_printf("trying to pseudo_exec null command\n");
|
|
_exit(EXIT_SUCCESS);
|
|
}
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
static const char *get_cmdtext(struct pipe *pi)
|
|
{
|
|
char **argv;
|
|
char *p;
|
|
int len;
|
|
|
|
/* This is subtle. ->cmdtext is created only on first backgrounding.
|
|
* (Think "cat, <ctrl-z>, fg, <ctrl-z>, fg, <ctrl-z>...." here...)
|
|
* On subsequent bg argv is trashed, but we won't use it */
|
|
if (pi->cmdtext)
|
|
return pi->cmdtext;
|
|
argv = pi->progs[0].argv;
|
|
if (!argv || !argv[0])
|
|
return (pi->cmdtext = xzalloc(1));
|
|
|
|
len = 0;
|
|
do len += strlen(*argv) + 1; while (*++argv);
|
|
pi->cmdtext = p = xmalloc(len);
|
|
argv = pi->progs[0].argv;
|
|
do {
|
|
len = strlen(*argv);
|
|
memcpy(p, *argv, len);
|
|
p += len;
|
|
*p++ = ' ';
|
|
} while (*++argv);
|
|
p[-1] = '\0';
|
|
return pi->cmdtext;
|
|
}
|
|
|
|
static void insert_bg_job(struct pipe *pi)
|
|
{
|
|
struct pipe *thejob;
|
|
int i;
|
|
|
|
/* Linear search for the ID of the job to use */
|
|
pi->jobid = 1;
|
|
for (thejob = job_list; thejob; thejob = thejob->next)
|
|
if (thejob->jobid >= pi->jobid)
|
|
pi->jobid = thejob->jobid + 1;
|
|
|
|
/* Add thejob to the list of running jobs */
|
|
if (!job_list) {
|
|
thejob = job_list = xmalloc(sizeof(*thejob));
|
|
} else {
|
|
for (thejob = job_list; thejob->next; thejob = thejob->next)
|
|
continue;
|
|
thejob->next = xmalloc(sizeof(*thejob));
|
|
thejob = thejob->next;
|
|
}
|
|
|
|
/* Physically copy the struct job */
|
|
memcpy(thejob, pi, sizeof(struct pipe));
|
|
thejob->progs = xzalloc(sizeof(pi->progs[0]) * pi->num_progs);
|
|
/* We cannot copy entire pi->progs[] vector! Double free()s will happen */
|
|
for (i = 0; i < pi->num_progs; i++) {
|
|
// TODO: do we really need to have so many fields which are just dead weight
|
|
// at execution stage?
|
|
thejob->progs[i].pid = pi->progs[i].pid;
|
|
/* all other fields are not used and stay zero */
|
|
}
|
|
thejob->next = NULL;
|
|
thejob->cmdtext = xstrdup(get_cmdtext(pi));
|
|
|
|
/* We don't wait for background thejobs to return -- append it
|
|
to the list of backgrounded thejobs and leave it alone */
|
|
printf("[%d] %d %s\n", thejob->jobid, thejob->progs[0].pid, thejob->cmdtext);
|
|
last_bg_pid = thejob->progs[0].pid;
|
|
last_jobid = thejob->jobid;
|
|
}
|
|
|
|
static void remove_bg_job(struct pipe *pi)
|
|
{
|
|
struct pipe *prev_pipe;
|
|
|
|
if (pi == job_list) {
|
|
job_list = pi->next;
|
|
} else {
|
|
prev_pipe = job_list;
|
|
while (prev_pipe->next != pi)
|
|
prev_pipe = prev_pipe->next;
|
|
prev_pipe->next = pi->next;
|
|
}
|
|
if (job_list)
|
|
last_jobid = job_list->jobid;
|
|
else
|
|
last_jobid = 0;
|
|
}
|
|
|
|
/* remove a backgrounded job */
|
|
static void delete_finished_bg_job(struct pipe *pi)
|
|
{
|
|
remove_bg_job(pi);
|
|
pi->stopped_progs = 0;
|
|
free_pipe(pi, 0);
|
|
free(pi);
|
|
}
|
|
#endif /* JOB */
|
|
|
|
/* Checks to see if any processes have exited -- if they
|
|
have, figure out why and see if a job has completed */
|
|
static int checkjobs(struct pipe* fg_pipe)
|
|
{
|
|
int attributes;
|
|
int status;
|
|
#if ENABLE_HUSH_JOB
|
|
int prognum = 0;
|
|
struct pipe *pi;
|
|
#endif
|
|
pid_t childpid;
|
|
int rcode = 0;
|
|
|
|
attributes = WUNTRACED;
|
|
if (fg_pipe == NULL) {
|
|
attributes |= WNOHANG;
|
|
}
|
|
|
|
/* Do we do this right?
|
|
* bash-3.00# sleep 20 | false
|
|
* <ctrl-Z pressed>
|
|
* [3]+ Stopped sleep 20 | false
|
|
* bash-3.00# echo $?
|
|
* 1 <========== bg pipe is not fully done, but exitcode is already known!
|
|
*/
|
|
|
|
//FIXME: non-interactive bash does not continue even if all processes in fg pipe
|
|
//are stopped. Testcase: "cat | cat" in a script (not on command line)
|
|
// + killall -STOP cat
|
|
|
|
wait_more:
|
|
while ((childpid = waitpid(-1, &status, attributes)) > 0) {
|
|
const int dead = WIFEXITED(status) || WIFSIGNALED(status);
|
|
|
|
#ifdef DEBUG_SHELL_JOBS
|
|
if (WIFSTOPPED(status))
|
|
debug_printf_jobs("pid %d stopped by sig %d (exitcode %d)\n",
|
|
childpid, WSTOPSIG(status), WEXITSTATUS(status));
|
|
if (WIFSIGNALED(status))
|
|
debug_printf_jobs("pid %d killed by sig %d (exitcode %d)\n",
|
|
childpid, WTERMSIG(status), WEXITSTATUS(status));
|
|
if (WIFEXITED(status))
|
|
debug_printf_jobs("pid %d exited, exitcode %d\n",
|
|
childpid, WEXITSTATUS(status));
|
|
#endif
|
|
/* Were we asked to wait for fg pipe? */
|
|
if (fg_pipe) {
|
|
int i;
|
|
for (i = 0; i < fg_pipe->num_progs; i++) {
|
|
debug_printf_jobs("check pid %d\n", fg_pipe->progs[i].pid);
|
|
if (fg_pipe->progs[i].pid == childpid) {
|
|
/* printf("process %d exit %d\n", i, WEXITSTATUS(status)); */
|
|
if (dead) {
|
|
fg_pipe->progs[i].pid = 0;
|
|
fg_pipe->running_progs--;
|
|
if (i == fg_pipe->num_progs-1)
|
|
/* last process gives overall exitstatus */
|
|
rcode = WEXITSTATUS(status);
|
|
} else {
|
|
fg_pipe->progs[i].is_stopped = 1;
|
|
fg_pipe->stopped_progs++;
|
|
}
|
|
debug_printf_jobs("fg_pipe: running_progs %d stopped_progs %d\n",
|
|
fg_pipe->running_progs, fg_pipe->stopped_progs);
|
|
if (fg_pipe->running_progs - fg_pipe->stopped_progs <= 0) {
|
|
/* All processes in fg pipe have exited/stopped */
|
|
#if ENABLE_HUSH_JOB
|
|
if (fg_pipe->running_progs)
|
|
insert_bg_job(fg_pipe);
|
|
#endif
|
|
return rcode;
|
|
}
|
|
/* There are still running processes in the fg pipe */
|
|
goto wait_more;
|
|
}
|
|
}
|
|
/* fall through to searching process in bg pipes */
|
|
}
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
/* We asked to wait for bg or orphaned children */
|
|
/* No need to remember exitcode in this case */
|
|
for (pi = job_list; pi; pi = pi->next) {
|
|
prognum = 0;
|
|
while (prognum < pi->num_progs) {
|
|
if (pi->progs[prognum].pid == childpid)
|
|
goto found_pi_and_prognum;
|
|
prognum++;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* Happens when shell is used as init process (init=/bin/sh) */
|
|
debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
|
|
goto wait_more;
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
found_pi_and_prognum:
|
|
if (dead) {
|
|
/* child exited */
|
|
pi->progs[prognum].pid = 0;
|
|
pi->running_progs--;
|
|
if (!pi->running_progs) {
|
|
printf(JOB_STATUS_FORMAT, pi->jobid,
|
|
"Done", pi->cmdtext);
|
|
delete_finished_bg_job(pi);
|
|
}
|
|
} else {
|
|
/* child stopped */
|
|
pi->stopped_progs++;
|
|
pi->progs[prognum].is_stopped = 1;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/* wait found no children or failed */
|
|
|
|
if (childpid && errno != ECHILD)
|
|
bb_perror_msg("waitpid");
|
|
return rcode;
|
|
}
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
static int checkjobs_and_fg_shell(struct pipe* fg_pipe)
|
|
{
|
|
pid_t p;
|
|
int rcode = checkjobs(fg_pipe);
|
|
/* Job finished, move the shell to the foreground */
|
|
p = getpgid(0); /* pgid of our process */
|
|
debug_printf_jobs("fg'ing ourself: getpgid(0)=%d\n", (int)p);
|
|
if (tcsetpgrp(interactive_fd, p) && errno != ENOTTY)
|
|
bb_perror_msg("tcsetpgrp-4a");
|
|
return rcode;
|
|
}
|
|
#endif
|
|
|
|
/* run_pipe_real() starts all the jobs, but doesn't wait for anything
|
|
* to finish. See checkjobs().
|
|
*
|
|
* return code is normally -1, when the caller has to wait for children
|
|
* to finish to determine the exit status of the pipe. If the pipe
|
|
* is a simple builtin command, however, the action is done by the
|
|
* time run_pipe_real returns, and the exit code is provided as the
|
|
* return value.
|
|
*
|
|
* The input of the pipe is always stdin, the output is always
|
|
* stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus,
|
|
* because it tries to avoid running the command substitution in
|
|
* subshell, when that is in fact necessary. The subshell process
|
|
* now has its stdout directed to the input of the appropriate pipe,
|
|
* so this routine is noticeably simpler.
|
|
*
|
|
* Returns -1 only if started some children. IOW: we have to
|
|
* mask out retvals of builtins etc with 0xff!
|
|
*/
|
|
static int run_pipe_real(struct pipe *pi)
|
|
{
|
|
int i;
|
|
int nextin, nextout;
|
|
int pipefds[2]; /* pipefds[0] is for reading */
|
|
struct child_prog *child;
|
|
const struct built_in_command *x;
|
|
char *p;
|
|
/* it is not always needed, but we aim to smaller code */
|
|
int squirrel[] = { -1, -1, -1 };
|
|
int rcode;
|
|
const int single_fg = (pi->num_progs == 1 && pi->followup != PIPE_BG);
|
|
|
|
debug_printf_exec("run_pipe_real start: single_fg=%d\n", single_fg);
|
|
|
|
nextin = 0;
|
|
#if ENABLE_HUSH_JOB
|
|
pi->pgrp = -1;
|
|
#endif
|
|
pi->running_progs = 1;
|
|
pi->stopped_progs = 0;
|
|
|
|
/* Check if this is a simple builtin (not part of a pipe).
|
|
* Builtins within pipes have to fork anyway, and are handled in
|
|
* pseudo_exec. "echo foo | read bar" doesn't work on bash, either.
|
|
*/
|
|
child = &(pi->progs[0]);
|
|
if (single_fg && child->group && child->subshell == 0) {
|
|
debug_printf("non-subshell grouping\n");
|
|
setup_redirects(child, squirrel);
|
|
debug_printf_exec(": run_list_real\n");
|
|
rcode = run_list_real(child->group);
|
|
restore_redirects(squirrel);
|
|
debug_printf_exec("run_pipe_real return %d\n", rcode);
|
|
return rcode; // do we need to add '... & 0xff' ?
|
|
}
|
|
|
|
if (single_fg && child->argv != NULL) {
|
|
char **argv_expanded;
|
|
char **argv = child->argv;
|
|
|
|
for (i = 0; is_assignment(argv[i]); i++)
|
|
continue;
|
|
if (i != 0 && argv[i] == NULL) {
|
|
/* assignments, but no command: set the local environment */
|
|
for (i = 0; argv[i] != NULL; i++) {
|
|
debug_printf("local environment set: %s\n", argv[i]);
|
|
p = expand_string_to_string(argv[i]);
|
|
set_local_var(p, 0);
|
|
}
|
|
return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
|
|
}
|
|
for (i = 0; is_assignment(argv[i]); i++) {
|
|
p = expand_string_to_string(argv[i]);
|
|
//sp: child->sp--;
|
|
putenv(p);
|
|
}
|
|
for (x = bltins; x->cmd; x++) {
|
|
if (strcmp(argv[i], x->cmd) == 0) {
|
|
if (x->function == builtin_exec && argv[i+1] == NULL) {
|
|
debug_printf("magic exec\n");
|
|
setup_redirects(child, NULL);
|
|
return EXIT_SUCCESS;
|
|
}
|
|
debug_printf("builtin inline %s\n", argv[0]);
|
|
/* XXX setup_redirects acts on file descriptors, not FILEs.
|
|
* This is perfect for work that comes after exec().
|
|
* Is it really safe for inline use? Experimentally,
|
|
* things seem to work with glibc. */
|
|
setup_redirects(child, squirrel);
|
|
debug_printf_exec(": builtin '%s' '%s'...\n", x->cmd, argv[i+1]);
|
|
//sp: if (child->sp) /* btw we can do it unconditionally... */
|
|
argv_expanded = expand_strvec_to_strvec(argv + i);
|
|
rcode = x->function(argv_expanded) & 0xff;
|
|
free(argv_expanded);
|
|
restore_redirects(squirrel);
|
|
debug_printf_exec("run_pipe_real return %d\n", rcode);
|
|
return rcode;
|
|
}
|
|
}
|
|
#if ENABLE_FEATURE_SH_STANDALONE
|
|
{
|
|
const struct bb_applet *a = find_applet_by_name(argv[i]);
|
|
if (a && a->nofork) {
|
|
setup_redirects(child, squirrel);
|
|
save_nofork_data(&nofork_save);
|
|
argv_expanded = argv + i;
|
|
//sp: if (child->sp)
|
|
argv_expanded = expand_strvec_to_strvec(argv + i);
|
|
debug_printf_exec(": run_nofork_applet '%s' '%s'...\n", argv_expanded[0], argv_expanded[1]);
|
|
rcode = run_nofork_applet_prime(&nofork_save, a, argv_expanded) & 0xff;
|
|
free(argv_expanded);
|
|
restore_redirects(squirrel);
|
|
debug_printf_exec("run_pipe_real return %d\n", rcode);
|
|
return rcode;
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/* Going to fork a child per each pipe member */
|
|
pi->running_progs = 0;
|
|
|
|
/* Disable job control signals for shell (parent) and
|
|
* for initial child code after fork */
|
|
set_jobctrl_sighandler(SIG_IGN);
|
|
|
|
for (i = 0; i < pi->num_progs; i++) {
|
|
child = &(pi->progs[i]);
|
|
if (child->argv)
|
|
debug_printf_exec(": pipe member '%s' '%s'...\n", child->argv[0], child->argv[1]);
|
|
else
|
|
debug_printf_exec(": pipe member with no argv\n");
|
|
|
|
/* pipes are inserted between pairs of commands */
|
|
if ((i + 1) < pi->num_progs) {
|
|
pipe(pipefds);
|
|
nextout = pipefds[1];
|
|
} else {
|
|
nextout = 1;
|
|
pipefds[0] = -1;
|
|
}
|
|
|
|
/* XXX test for failed fork()? */
|
|
#if BB_MMU
|
|
child->pid = fork();
|
|
#else
|
|
child->pid = vfork();
|
|
#endif
|
|
if (!child->pid) { /* child */
|
|
/* Every child adds itself to new process group
|
|
* with pgid == pid of first child in pipe */
|
|
#if ENABLE_HUSH_JOB
|
|
if (run_list_level == 1 && interactive_fd) {
|
|
/* Don't do pgrp restore anymore on fatal signals */
|
|
set_fatal_sighandler(SIG_DFL);
|
|
if (pi->pgrp < 0) /* true for 1st process only */
|
|
pi->pgrp = getpid();
|
|
if (setpgid(0, pi->pgrp) == 0 && pi->followup != PIPE_BG) {
|
|
/* We do it in *every* child, not just first,
|
|
* to avoid races */
|
|
tcsetpgrp(interactive_fd, pi->pgrp);
|
|
}
|
|
}
|
|
#endif
|
|
/* in non-interactive case fatal sigs are already SIG_DFL */
|
|
close_all();
|
|
if (nextin != 0) {
|
|
dup2(nextin, 0);
|
|
close(nextin);
|
|
}
|
|
if (nextout != 1) {
|
|
dup2(nextout, 1);
|
|
close(nextout);
|
|
}
|
|
if (pipefds[0] != -1) {
|
|
close(pipefds[0]); /* opposite end of our output pipe */
|
|
}
|
|
/* Like bash, explicit redirects override pipes,
|
|
* and the pipe fd is available for dup'ing. */
|
|
setup_redirects(child, NULL);
|
|
|
|
/* Restore default handlers just prior to exec */
|
|
set_jobctrl_sighandler(SIG_DFL);
|
|
set_misc_sighandler(SIG_DFL);
|
|
signal(SIGCHLD, SIG_DFL);
|
|
pseudo_exec(child);
|
|
}
|
|
|
|
pi->running_progs++;
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
/* Second and next children need to know pid of first one */
|
|
if (pi->pgrp < 0)
|
|
pi->pgrp = child->pid;
|
|
#endif
|
|
if (nextin != 0)
|
|
close(nextin);
|
|
if (nextout != 1)
|
|
close(nextout);
|
|
|
|
/* If there isn't another process, nextin is garbage
|
|
but it doesn't matter */
|
|
nextin = pipefds[0];
|
|
}
|
|
debug_printf_exec("run_pipe_real return -1\n");
|
|
return -1;
|
|
}
|
|
|
|
#ifndef debug_print_tree
|
|
static void debug_print_tree(struct pipe *pi, int lvl)
|
|
{
|
|
static const char *PIPE[] = {
|
|
[PIPE_SEQ] = "SEQ",
|
|
[PIPE_AND] = "AND",
|
|
[PIPE_OR ] = "OR" ,
|
|
[PIPE_BG ] = "BG" ,
|
|
};
|
|
static const char *RES[] = {
|
|
[RES_NONE ] = "NONE" ,
|
|
#if ENABLE_HUSH_IF
|
|
[RES_IF ] = "IF" ,
|
|
[RES_THEN ] = "THEN" ,
|
|
[RES_ELIF ] = "ELIF" ,
|
|
[RES_ELSE ] = "ELSE" ,
|
|
[RES_FI ] = "FI" ,
|
|
#endif
|
|
#if ENABLE_HUSH_LOOPS
|
|
[RES_FOR ] = "FOR" ,
|
|
[RES_WHILE] = "WHILE",
|
|
[RES_UNTIL] = "UNTIL",
|
|
[RES_DO ] = "DO" ,
|
|
[RES_DONE ] = "DONE" ,
|
|
[RES_IN ] = "IN" ,
|
|
#endif
|
|
[RES_XXXX ] = "XXXX" ,
|
|
[RES_SNTX ] = "SNTX" ,
|
|
};
|
|
|
|
int pin, prn;
|
|
|
|
pin = 0;
|
|
while (pi) {
|
|
fprintf(stderr, "%*spipe %d res_word=%s followup=%d %s\n", lvl*2, "",
|
|
pin, RES[pi->res_word], pi->followup, PIPE[pi->followup]);
|
|
prn = 0;
|
|
while (prn < pi->num_progs) {
|
|
struct child_prog *child = &pi->progs[prn];
|
|
char **argv = child->argv;
|
|
|
|
fprintf(stderr, "%*s prog %d", lvl*2, "", prn);
|
|
if (child->group) {
|
|
fprintf(stderr, " group %s: (argv=%p)\n",
|
|
(child->subshell ? "()" : "{}"),
|
|
argv);
|
|
debug_print_tree(child->group, lvl+1);
|
|
prn++;
|
|
continue;
|
|
}
|
|
if (argv) while (*argv) {
|
|
fprintf(stderr, " '%s'", *argv);
|
|
argv++;
|
|
}
|
|
fprintf(stderr, "\n");
|
|
prn++;
|
|
}
|
|
pi = pi->next;
|
|
pin++;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/* NB: called by pseudo_exec, and therefore must not modify any
|
|
* global data until exec/_exit (we can be a child after vfork!) */
|
|
static int run_list_real(struct pipe *pi)
|
|
{
|
|
struct pipe *rpipe;
|
|
#if ENABLE_HUSH_LOOPS
|
|
char *for_varname = NULL;
|
|
char **for_lcur = NULL;
|
|
char **for_list = NULL;
|
|
int flag_rep = 0;
|
|
#endif
|
|
int save_num_progs;
|
|
int flag_skip = 1;
|
|
int rcode = 0; /* probably for gcc only */
|
|
int flag_restore = 0;
|
|
#if ENABLE_HUSH_IF
|
|
int if_code = 0, next_if_code = 0; /* need double-buffer to handle elif */
|
|
#else
|
|
enum { if_code = 0, next_if_code = 0 };
|
|
#endif
|
|
reserved_style rword;
|
|
reserved_style skip_more_for_this_rword = RES_XXXX;
|
|
|
|
debug_printf_exec("run_list_real start lvl %d\n", run_list_level + 1);
|
|
|
|
#if ENABLE_HUSH_LOOPS
|
|
/* check syntax for "for" */
|
|
for (rpipe = pi; rpipe; rpipe = rpipe->next) {
|
|
if ((rpipe->res_word == RES_IN || rpipe->res_word == RES_FOR)
|
|
&& (rpipe->next == NULL)
|
|
) {
|
|
syntax("malformed for"); /* no IN or no commands after IN */
|
|
debug_printf_exec("run_list_real lvl %d return 1\n", run_list_level);
|
|
return 1;
|
|
}
|
|
if ((rpipe->res_word == RES_IN && rpipe->next->res_word == RES_IN && rpipe->next->progs[0].argv != NULL)
|
|
|| (rpipe->res_word == RES_FOR && rpipe->next->res_word != RES_IN)
|
|
) {
|
|
/* TODO: what is tested in the first condition? */
|
|
syntax("malformed for"); /* 2nd condition: not followed by IN */
|
|
debug_printf_exec("run_list_real lvl %d return 1\n", run_list_level);
|
|
return 1;
|
|
}
|
|
}
|
|
#else
|
|
rpipe = NULL;
|
|
#endif
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
/* Example of nested list: "while true; do { sleep 1 | exit 2; } done".
|
|
* We are saving state before entering outermost list ("while...done")
|
|
* so that ctrl-Z will correctly background _entire_ outermost list,
|
|
* not just a part of it (like "sleep 1 | exit 2") */
|
|
if (++run_list_level == 1 && interactive_fd) {
|
|
if (sigsetjmp(toplevel_jb, 1)) {
|
|
/* ctrl-Z forked and we are parent; or ctrl-C.
|
|
* Sighandler has longjmped us here */
|
|
signal(SIGINT, SIG_IGN);
|
|
signal(SIGTSTP, SIG_IGN);
|
|
/* Restore level (we can be coming from deep inside
|
|
* nested levels) */
|
|
run_list_level = 1;
|
|
#if ENABLE_FEATURE_SH_STANDALONE
|
|
if (nofork_save.saved) { /* if save area is valid */
|
|
debug_printf_jobs("exiting nofork early\n");
|
|
restore_nofork_data(&nofork_save);
|
|
}
|
|
#endif
|
|
if (ctrl_z_flag) {
|
|
/* ctrl-Z has forked and stored pid of the child in pi->pid.
|
|
* Remember this child as background job */
|
|
insert_bg_job(pi);
|
|
} else {
|
|
/* ctrl-C. We just stop doing whatever we were doing */
|
|
putchar('\n');
|
|
}
|
|
rcode = 0;
|
|
goto ret;
|
|
}
|
|
/* ctrl-Z handler will store pid etc in pi */
|
|
toplevel_list = pi;
|
|
ctrl_z_flag = 0;
|
|
#if ENABLE_FEATURE_SH_STANDALONE
|
|
nofork_save.saved = 0; /* in case we will run a nofork later */
|
|
#endif
|
|
signal_SA_RESTART(SIGTSTP, handler_ctrl_z);
|
|
signal(SIGINT, handler_ctrl_c);
|
|
}
|
|
#endif
|
|
|
|
for (; pi; pi = flag_restore ? rpipe : pi->next) {
|
|
rword = pi->res_word;
|
|
#if ENABLE_HUSH_LOOPS
|
|
if (rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR) {
|
|
flag_restore = 0;
|
|
if (!rpipe) {
|
|
flag_rep = 0;
|
|
rpipe = pi;
|
|
}
|
|
}
|
|
#endif
|
|
debug_printf_exec(": rword=%d if_code=%d next_if_code=%d skip_more=%d\n",
|
|
rword, if_code, next_if_code, skip_more_for_this_rword);
|
|
if (rword == skip_more_for_this_rword && flag_skip) {
|
|
if (pi->followup == PIPE_SEQ)
|
|
flag_skip = 0;
|
|
continue;
|
|
}
|
|
flag_skip = 1;
|
|
skip_more_for_this_rword = RES_XXXX;
|
|
#if ENABLE_HUSH_IF
|
|
if (rword == RES_THEN || rword == RES_ELSE)
|
|
if_code = next_if_code;
|
|
if (rword == RES_THEN && if_code)
|
|
continue;
|
|
if (rword == RES_ELSE && !if_code)
|
|
continue;
|
|
if (rword == RES_ELIF && !if_code)
|
|
break;
|
|
#endif
|
|
#if ENABLE_HUSH_LOOPS
|
|
if (rword == RES_FOR && pi->num_progs) {
|
|
if (!for_lcur) {
|
|
/* if no variable values after "in" we skip "for" */
|
|
if (!pi->next->progs->argv)
|
|
continue;
|
|
/* create list of variable values */
|
|
for_list = expand_strvec_to_strvec(pi->next->progs->argv);
|
|
for_lcur = for_list;
|
|
for_varname = pi->progs->argv[0];
|
|
pi->progs->argv[0] = NULL;
|
|
flag_rep = 1;
|
|
}
|
|
free(pi->progs->argv[0]);
|
|
if (!*for_lcur) {
|
|
free(for_list);
|
|
for_lcur = NULL;
|
|
flag_rep = 0;
|
|
pi->progs->argv[0] = for_varname;
|
|
pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
|
|
continue;
|
|
}
|
|
/* insert next value from for_lcur */
|
|
/* vda: does it need escaping? */
|
|
pi->progs->argv[0] = xasprintf("%s=%s", for_varname, *for_lcur++);
|
|
pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0];
|
|
}
|
|
if (rword == RES_IN)
|
|
continue;
|
|
if (rword == RES_DO) {
|
|
if (!flag_rep)
|
|
continue;
|
|
}
|
|
if (rword == RES_DONE) {
|
|
if (flag_rep) {
|
|
flag_restore = 1;
|
|
} else {
|
|
rpipe = NULL;
|
|
}
|
|
}
|
|
#endif
|
|
if (pi->num_progs == 0)
|
|
continue;
|
|
save_num_progs = pi->num_progs; /* save number of programs */
|
|
debug_printf_exec(": run_pipe_real with %d members\n", pi->num_progs);
|
|
rcode = run_pipe_real(pi);
|
|
if (rcode != -1) {
|
|
/* We only ran a builtin: rcode was set by the return value
|
|
* of run_pipe_real(), and we don't need to wait for anything. */
|
|
} else if (pi->followup == PIPE_BG) {
|
|
/* What does bash do with attempts to background builtins? */
|
|
/* Even bash 3.2 doesn't do that well with nested bg:
|
|
* try "{ { sleep 10; echo DEEP; } & echo HERE; } &".
|
|
* I'm NOT treating inner &'s as jobs */
|
|
#if ENABLE_HUSH_JOB
|
|
if (run_list_level == 1)
|
|
insert_bg_job(pi);
|
|
#endif
|
|
rcode = EXIT_SUCCESS;
|
|
} else {
|
|
#if ENABLE_HUSH_JOB
|
|
/* Paranoia, just "interactive_fd" should be enough? */
|
|
if (run_list_level == 1 && interactive_fd) {
|
|
/* waits for completion, then fg's main shell */
|
|
rcode = checkjobs_and_fg_shell(pi);
|
|
} else
|
|
#endif
|
|
{
|
|
/* this one just waits for completion */
|
|
rcode = checkjobs(pi);
|
|
}
|
|
debug_printf_exec(": checkjobs returned %d\n", rcode);
|
|
}
|
|
debug_printf_exec(": setting last_return_code=%d\n", rcode);
|
|
last_return_code = rcode;
|
|
pi->num_progs = save_num_progs; /* restore number of programs */
|
|
#if ENABLE_HUSH_IF
|
|
if (rword == RES_IF || rword == RES_ELIF)
|
|
next_if_code = rcode; /* can be overwritten a number of times */
|
|
#endif
|
|
#if ENABLE_HUSH_LOOPS
|
|
if (rword == RES_WHILE)
|
|
flag_rep = !last_return_code;
|
|
if (rword == RES_UNTIL)
|
|
flag_rep = last_return_code;
|
|
#endif
|
|
if ((rcode == EXIT_SUCCESS && pi->followup == PIPE_OR)
|
|
|| (rcode != EXIT_SUCCESS && pi->followup == PIPE_AND)
|
|
) {
|
|
skip_more_for_this_rword = rword;
|
|
}
|
|
checkjobs(NULL);
|
|
}
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
if (ctrl_z_flag) {
|
|
/* ctrl-Z forked somewhere in the past, we are the child,
|
|
* and now we completed running the list. Exit. */
|
|
exit(rcode);
|
|
}
|
|
ret:
|
|
if (!--run_list_level && interactive_fd) {
|
|
signal(SIGTSTP, SIG_IGN);
|
|
signal(SIGINT, SIG_IGN);
|
|
}
|
|
#endif
|
|
debug_printf_exec("run_list_real lvl %d return %d\n", run_list_level + 1, rcode);
|
|
return rcode;
|
|
}
|
|
|
|
/* return code is the exit status of the pipe */
|
|
static int free_pipe(struct pipe *pi, int indent)
|
|
{
|
|
char **p;
|
|
struct child_prog *child;
|
|
struct redir_struct *r, *rnext;
|
|
int a, i, ret_code = 0;
|
|
|
|
if (pi->stopped_progs > 0)
|
|
return ret_code;
|
|
debug_printf_clean("%s run pipe: (pid %d)\n", indenter(indent), getpid());
|
|
for (i = 0; i < pi->num_progs; i++) {
|
|
child = &pi->progs[i];
|
|
debug_printf_clean("%s command %d:\n", indenter(indent), i);
|
|
if (child->argv) {
|
|
for (a = 0, p = child->argv; *p; a++, p++) {
|
|
debug_printf_clean("%s argv[%d] = %s\n", indenter(indent), a, *p);
|
|
}
|
|
globfree(&child->glob_result);
|
|
child->argv = NULL;
|
|
} else if (child->group) {
|
|
debug_printf_clean("%s begin group (subshell:%d)\n", indenter(indent), child->subshell);
|
|
ret_code = free_pipe_list(child->group, indent+3);
|
|
debug_printf_clean("%s end group\n", indenter(indent));
|
|
} else {
|
|
debug_printf_clean("%s (nil)\n", indenter(indent));
|
|
}
|
|
for (r = child->redirects; r; r = rnext) {
|
|
debug_printf_clean("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->type].descrip);
|
|
if (r->dup == -1) {
|
|
/* guard against the case >$FOO, where foo is unset or blank */
|
|
if (r->word.gl_pathv) {
|
|
debug_printf_clean(" %s\n", *r->word.gl_pathv);
|
|
globfree(&r->word);
|
|
}
|
|
} else {
|
|
debug_printf_clean("&%d\n", r->dup);
|
|
}
|
|
rnext = r->next;
|
|
free(r);
|
|
}
|
|
child->redirects = NULL;
|
|
}
|
|
free(pi->progs); /* children are an array, they get freed all at once */
|
|
pi->progs = NULL;
|
|
#if ENABLE_HUSH_JOB
|
|
free(pi->cmdtext);
|
|
pi->cmdtext = NULL;
|
|
#endif
|
|
return ret_code;
|
|
}
|
|
|
|
static int free_pipe_list(struct pipe *head, int indent)
|
|
{
|
|
int rcode = 0; /* if list has no members */
|
|
struct pipe *pi, *next;
|
|
|
|
for (pi = head; pi; pi = next) {
|
|
debug_printf_clean("%s pipe reserved mode %d\n", indenter(indent), pi->res_word);
|
|
rcode = free_pipe(pi, indent);
|
|
debug_printf_clean("%s pipe followup code %d\n", indenter(indent), pi->followup);
|
|
next = pi->next;
|
|
/*pi->next = NULL;*/
|
|
free(pi);
|
|
}
|
|
return rcode;
|
|
}
|
|
|
|
/* Select which version we will use */
|
|
static int run_list(struct pipe *pi)
|
|
{
|
|
int rcode = 0;
|
|
debug_printf_exec("run_list entered\n");
|
|
if (fake_mode == 0) {
|
|
debug_printf_exec(": run_list_real with %d members\n", pi->num_progs);
|
|
rcode = run_list_real(pi);
|
|
}
|
|
/* free_pipe_list has the side effect of clearing memory.
|
|
* In the long run that function can be merged with run_list_real,
|
|
* but doing that now would hobble the debugging effort. */
|
|
free_pipe_list(pi, 0);
|
|
debug_printf_exec("run_list return %d\n", rcode);
|
|
return rcode;
|
|
}
|
|
|
|
/* The API for glob is arguably broken. This routine pushes a non-matching
|
|
* string into the output structure, removing non-backslashed backslashes.
|
|
* If someone can prove me wrong, by performing this function within the
|
|
* original glob(3) api, feel free to rewrite this routine into oblivion.
|
|
* Return code (0 vs. GLOB_NOSPACE) matches glob(3).
|
|
* XXX broken if the last character is '\\', check that before calling.
|
|
*/
|
|
static int globhack(const char *src, int flags, glob_t *pglob)
|
|
{
|
|
int cnt = 0, pathc;
|
|
const char *s;
|
|
char *dest;
|
|
for (cnt = 1, s = src; s && *s; s++) {
|
|
if (*s == '\\') s++;
|
|
cnt++;
|
|
}
|
|
dest = xmalloc(cnt);
|
|
if (!(flags & GLOB_APPEND)) {
|
|
pglob->gl_pathv = NULL;
|
|
pglob->gl_pathc = 0;
|
|
pglob->gl_offs = 0;
|
|
pglob->gl_offs = 0;
|
|
}
|
|
pathc = ++pglob->gl_pathc;
|
|
pglob->gl_pathv = xrealloc(pglob->gl_pathv, (pathc+1) * sizeof(*pglob->gl_pathv));
|
|
pglob->gl_pathv[pathc-1] = dest;
|
|
pglob->gl_pathv[pathc] = NULL;
|
|
for (s = src; s && *s; s++, dest++) {
|
|
if (*s == '\\') s++;
|
|
*dest = *s;
|
|
}
|
|
*dest = '\0';
|
|
return 0;
|
|
}
|
|
|
|
/* XXX broken if the last character is '\\', check that before calling */
|
|
static int glob_needed(const char *s)
|
|
{
|
|
for (; *s; s++) {
|
|
if (*s == '\\') s++;
|
|
if (strchr("*[?", *s)) return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int xglob(o_string *dest, int flags, glob_t *pglob)
|
|
{
|
|
int gr;
|
|
|
|
/* short-circuit for null word */
|
|
/* we can code this better when the debug_printf's are gone */
|
|
if (dest->length == 0) {
|
|
if (dest->nonnull) {
|
|
/* bash man page calls this an "explicit" null */
|
|
gr = globhack(dest->data, flags, pglob);
|
|
debug_printf("globhack returned %d\n", gr);
|
|
} else {
|
|
return 0;
|
|
}
|
|
} else if (glob_needed(dest->data)) {
|
|
gr = glob(dest->data, flags, NULL, pglob);
|
|
debug_printf("glob returned %d\n", gr);
|
|
if (gr == GLOB_NOMATCH) {
|
|
/* quote removal, or more accurately, backslash removal */
|
|
gr = globhack(dest->data, flags, pglob);
|
|
debug_printf("globhack returned %d\n", gr);
|
|
}
|
|
} else {
|
|
gr = globhack(dest->data, flags, pglob);
|
|
debug_printf("globhack returned %d\n", gr);
|
|
}
|
|
if (gr == GLOB_NOSPACE)
|
|
bb_error_msg_and_die("out of memory during glob");
|
|
if (gr != 0) { /* GLOB_ABORTED ? */
|
|
bb_error_msg("glob(3) error %d", gr);
|
|
}
|
|
/* globprint(glob_target); */
|
|
return gr;
|
|
}
|
|
|
|
/* expand_strvec_to_strvec() takes a list of strings, expands
|
|
* all variable references within and returns a pointer to
|
|
* a list of expanded strings, possibly with larger number
|
|
* of strings. (Think VAR="a b"; echo $VAR).
|
|
* This new list is allocated as a single malloc block.
|
|
* NULL-terminated list of char* pointers is at the beginning of it,
|
|
* followed by strings themself.
|
|
* Caller can deallocate entire list by single free(list). */
|
|
|
|
/* Helpers first:
|
|
* count_XXX estimates size of the block we need. It's okay
|
|
* to over-estimate sizes a bit, if it makes code simpler */
|
|
static int count_ifs(const char *str)
|
|
{
|
|
int cnt = 0;
|
|
debug_printf_expand("count_ifs('%s') ifs='%s'", str, ifs);
|
|
while (1) {
|
|
str += strcspn(str, ifs);
|
|
if (!*str) break;
|
|
str++; /* str += strspn(str, ifs); */
|
|
cnt++; /* cnt += strspn(str, ifs); - but this code is larger */
|
|
}
|
|
debug_printf_expand(" return %d\n", cnt);
|
|
return cnt;
|
|
}
|
|
|
|
static void count_var_expansion_space(int *countp, int *lenp, char *arg)
|
|
{
|
|
char first_ch;
|
|
int i;
|
|
int len = *lenp;
|
|
int count = *countp;
|
|
const char *val;
|
|
char *p;
|
|
|
|
while ((p = strchr(arg, SPECIAL_VAR_SYMBOL))) {
|
|
len += p - arg;
|
|
arg = ++p;
|
|
p = strchr(p, SPECIAL_VAR_SYMBOL);
|
|
first_ch = arg[0];
|
|
|
|
switch (first_ch & 0x7f) {
|
|
/* high bit in 1st_ch indicates that var is double-quoted */
|
|
case '$': /* pid */
|
|
case '!': /* bg pid */
|
|
case '?': /* exitcode */
|
|
case '#': /* argc */
|
|
len += sizeof(int)*3 + 1; /* enough for int */
|
|
break;
|
|
case '*':
|
|
case '@':
|
|
for (i = 1; i < global_argc; i++) {
|
|
len += strlen(global_argv[i]) + 1;
|
|
count++;
|
|
if (!(first_ch & 0x80))
|
|
count += count_ifs(global_argv[i]);
|
|
}
|
|
break;
|
|
default:
|
|
*p = '\0';
|
|
arg[0] = first_ch & 0x7f;
|
|
if (isdigit(arg[0])) {
|
|
i = xatoi_u(arg);
|
|
val = NULL;
|
|
if (i < global_argc)
|
|
val = global_argv[i];
|
|
} else
|
|
val = lookup_param(arg);
|
|
arg[0] = first_ch;
|
|
*p = SPECIAL_VAR_SYMBOL;
|
|
|
|
if (val) {
|
|
len += strlen(val) + 1;
|
|
if (!(first_ch & 0x80))
|
|
count += count_ifs(val);
|
|
}
|
|
}
|
|
arg = ++p;
|
|
}
|
|
|
|
len += strlen(arg) + 1;
|
|
count++;
|
|
*lenp = len;
|
|
*countp = count;
|
|
}
|
|
|
|
/* Store given string, finalizing the word and starting new one whenever
|
|
* we encounter ifs char(s). This is used for expanding variable values.
|
|
* End-of-string does NOT finalize word: think about 'echo -$VAR-' */
|
|
static int expand_on_ifs(char **list, int n, char **posp, const char *str)
|
|
{
|
|
char *pos = *posp;
|
|
while (1) {
|
|
int word_len = strcspn(str, ifs);
|
|
if (word_len) {
|
|
memcpy(pos, str, word_len); /* store non-ifs chars */
|
|
pos += word_len;
|
|
str += word_len;
|
|
}
|
|
if (!*str) /* EOL - do not finalize word */
|
|
break;
|
|
*pos++ = '\0';
|
|
if (n) debug_printf_expand("expand_on_ifs finalized list[%d]=%p '%s' "
|
|
"strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1],
|
|
strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos);
|
|
list[n++] = pos;
|
|
str += strspn(str, ifs); /* skip ifs chars */
|
|
}
|
|
*posp = pos;
|
|
return n;
|
|
}
|
|
|
|
/* Expand all variable references in given string, adding words to list[]
|
|
* at n, n+1,... positions. Return updated n (so that list[n] is next one
|
|
* to be filled). This routine is extremely tricky: has to deal with
|
|
* variables/parameters with whitespace, $* and $@, and constructs like
|
|
* 'echo -$*-'. If you play here, you must run testsuite afterwards! */
|
|
/* NB: another bug is that we cannot detect empty strings yet:
|
|
* "" or $empty"" expands to zero words, has to expand to empty word */
|
|
static int expand_vars_to_list(char **list, int n, char **posp, char *arg, char or_mask)
|
|
{
|
|
/* or_mask is either 0 (normal case) or 0x80
|
|
* (expansion of right-hand side of assignment == 1-element expand) */
|
|
|
|
char first_ch, ored_ch;
|
|
int i;
|
|
const char *val;
|
|
char *p;
|
|
char *pos = *posp;
|
|
|
|
ored_ch = 0;
|
|
|
|
if (n) debug_printf_expand("expand_vars_to_list finalized list[%d]=%p '%s' "
|
|
"strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1],
|
|
strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos);
|
|
list[n++] = pos;
|
|
|
|
while ((p = strchr(arg, SPECIAL_VAR_SYMBOL))) {
|
|
memcpy(pos, arg, p - arg);
|
|
pos += (p - arg);
|
|
arg = ++p;
|
|
p = strchr(p, SPECIAL_VAR_SYMBOL);
|
|
|
|
first_ch = arg[0] | or_mask; /* forced to "quoted" if or_mask = 0x80 */
|
|
ored_ch |= first_ch;
|
|
val = NULL;
|
|
switch (first_ch & 0x7f) {
|
|
/* Highest bit in first_ch indicates that var is double-quoted */
|
|
case '$': /* pid */
|
|
/* FIXME: (echo $$) should still print pid of main shell */
|
|
val = utoa(getpid());
|
|
break;
|
|
case '!': /* bg pid */
|
|
val = last_bg_pid ? utoa(last_bg_pid) : (char*)"";
|
|
break;
|
|
case '?': /* exitcode */
|
|
val = utoa(last_return_code);
|
|
break;
|
|
case '#': /* argc */
|
|
val = utoa(global_argc ? global_argc-1 : 0);
|
|
break;
|
|
case '*':
|
|
case '@':
|
|
i = 1;
|
|
if (!(first_ch & 0x80)) { /* unquoted $* or $@ */
|
|
while (i < global_argc) {
|
|
n = expand_on_ifs(list, n, &pos, global_argv[i]);
|
|
debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, global_argc-1);
|
|
if (global_argv[i++][0] && i < global_argc) {
|
|
/* this argv[] is not empty and not last:
|
|
* put terminating NUL, start new word */
|
|
*pos++ = '\0';
|
|
if (n) debug_printf_expand("expand_vars_to_list 2 finalized list[%d]=%p '%s' "
|
|
"strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1],
|
|
strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos);
|
|
list[n++] = pos;
|
|
}
|
|
}
|
|
} else
|
|
/* If or_mask is nonzero, we handle assignment 'a=....$@.....'
|
|
* and in this case should theat it like '$*' */
|
|
if (first_ch == ('@'|0x80) && !or_mask) { /* quoted $@ */
|
|
while (1) {
|
|
strcpy(pos, global_argv[i]);
|
|
pos += strlen(global_argv[i]);
|
|
if (++i >= global_argc)
|
|
break;
|
|
*pos++ = '\0';
|
|
if (n) debug_printf_expand("expand_vars_to_list 3 finalized list[%d]=%p '%s' "
|
|
"strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1],
|
|
strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos);
|
|
list[n++] = pos;
|
|
}
|
|
} else { /* quoted $*: add as one word */
|
|
while (1) {
|
|
strcpy(pos, global_argv[i]);
|
|
pos += strlen(global_argv[i]);
|
|
if (++i >= global_argc)
|
|
break;
|
|
if (ifs[0])
|
|
*pos++ = ifs[0];
|
|
}
|
|
}
|
|
break;
|
|
default:
|
|
*p = '\0';
|
|
arg[0] = first_ch & 0x7f;
|
|
if (isdigit(arg[0])) {
|
|
i = xatoi_u(arg);
|
|
val = NULL;
|
|
if (i < global_argc)
|
|
val = global_argv[i];
|
|
} else
|
|
val = lookup_param(arg);
|
|
arg[0] = first_ch;
|
|
*p = SPECIAL_VAR_SYMBOL;
|
|
if (!(first_ch & 0x80)) { /* unquoted $VAR */
|
|
if (val) {
|
|
n = expand_on_ifs(list, n, &pos, val);
|
|
val = NULL;
|
|
}
|
|
} /* else: quoted $VAR, val will be appended at pos */
|
|
}
|
|
if (val) {
|
|
strcpy(pos, val);
|
|
pos += strlen(val);
|
|
}
|
|
arg = ++p;
|
|
}
|
|
debug_printf_expand("expand_vars_to_list adding tail '%s' at %p\n", arg, pos);
|
|
strcpy(pos, arg);
|
|
pos += strlen(arg) + 1;
|
|
if (pos == list[n-1] + 1) { /* expansion is empty */
|
|
if (!(ored_ch & 0x80)) { /* all vars were not quoted... */
|
|
debug_printf_expand("expand_vars_to_list list[%d] empty, going back\n", n);
|
|
pos--;
|
|
n--;
|
|
}
|
|
}
|
|
|
|
*posp = pos;
|
|
return n;
|
|
}
|
|
|
|
static char **expand_variables(char **argv, char or_mask)
|
|
{
|
|
int n;
|
|
int count = 1;
|
|
int len = 0;
|
|
char *pos, **v, **list;
|
|
|
|
v = argv;
|
|
if (!*v) debug_printf_expand("count_var_expansion_space: "
|
|
"argv[0]=NULL count=%d len=%d alloc_space=%d\n",
|
|
count, len, sizeof(char*) * count + len);
|
|
while (*v) {
|
|
count_var_expansion_space(&count, &len, *v);
|
|
debug_printf_expand("count_var_expansion_space: "
|
|
"'%s' count=%d len=%d alloc_space=%d\n",
|
|
*v, count, len, sizeof(char*) * count + len);
|
|
v++;
|
|
}
|
|
len += sizeof(char*) * count; /* total to alloc */
|
|
list = xmalloc(len);
|
|
pos = (char*)(list + count);
|
|
debug_printf_expand("list=%p, list[0] should be %p\n", list, pos);
|
|
n = 0;
|
|
v = argv;
|
|
while (*v)
|
|
n = expand_vars_to_list(list, n, &pos, *v++, or_mask);
|
|
|
|
if (n) debug_printf_expand("finalized list[%d]=%p '%s' "
|
|
"strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1],
|
|
strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos);
|
|
list[n] = NULL;
|
|
|
|
#ifdef DEBUG_EXPAND
|
|
{
|
|
int m = 0;
|
|
while (m <= n) {
|
|
debug_printf_expand("list[%d]=%p '%s'\n", m, list[m], list[m]);
|
|
m++;
|
|
}
|
|
debug_printf_expand("used_space=%d\n", pos - (char*)list);
|
|
}
|
|
#endif
|
|
if (ENABLE_HUSH_DEBUG)
|
|
if (pos - (char*)list > len)
|
|
bb_error_msg_and_die("BUG in varexp");
|
|
return list;
|
|
}
|
|
|
|
static char **expand_strvec_to_strvec(char **argv)
|
|
{
|
|
return expand_variables(argv, 0);
|
|
}
|
|
|
|
static char *expand_string_to_string(const char *str)
|
|
{
|
|
char *argv[2], **list;
|
|
|
|
argv[0] = (char*)str;
|
|
argv[1] = NULL;
|
|
list = expand_variables(argv, 0x80); /* 0x80: make one-element expansion */
|
|
if (ENABLE_HUSH_DEBUG)
|
|
if (!list[0] || list[1])
|
|
bb_error_msg_and_die("BUG in varexp2");
|
|
/* actually, just move string 2*sizeof(char*) bytes back */
|
|
strcpy((char*)list, list[0]);
|
|
debug_printf_expand("string_to_string='%s'\n", (char*)list);
|
|
return (char*)list;
|
|
}
|
|
|
|
static char* expand_strvec_to_string(char **argv)
|
|
{
|
|
char **list;
|
|
|
|
list = expand_variables(argv, 0x80);
|
|
/* Convert all NULs to spaces */
|
|
if (list[0]) {
|
|
int n = 1;
|
|
while (list[n]) {
|
|
if (ENABLE_HUSH_DEBUG)
|
|
if (list[n-1] + strlen(list[n-1]) + 1 != list[n])
|
|
bb_error_msg_and_die("BUG in varexp3");
|
|
list[n][-1] = ' '; /* TODO: or to ifs[0]? */
|
|
n++;
|
|
}
|
|
}
|
|
strcpy((char*)list, list[0]);
|
|
debug_printf_expand("strvec_to_string='%s'\n", (char*)list);
|
|
return (char*)list;
|
|
}
|
|
|
|
/* This is used to get/check local shell variables */
|
|
static struct variable *get_local_var(const char *name)
|
|
{
|
|
struct variable *cur;
|
|
int len;
|
|
|
|
if (!name)
|
|
return NULL;
|
|
len = strlen(name);
|
|
for (cur = top_var; cur; cur = cur->next) {
|
|
if (strncmp(cur->varstr, name, len) == 0 && cur->varstr[len] == '=')
|
|
return cur;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/* str holds "NAME=VAL" and is expected to be malloced.
|
|
* We take ownership of it. */
|
|
static int set_local_var(char *str, int flg_export)
|
|
{
|
|
struct variable *cur;
|
|
char *value;
|
|
int name_len;
|
|
|
|
value = strchr(str, '=');
|
|
if (!value) { /* not expected to ever happen? */
|
|
free(str);
|
|
return -1;
|
|
}
|
|
|
|
name_len = value - str + 1; /* including '=' */
|
|
cur = top_var; /* cannot be NULL (we have HUSH_VERSION and it's RO) */
|
|
while (1) {
|
|
if (strncmp(cur->varstr, str, name_len) != 0) {
|
|
if (!cur->next) {
|
|
/* Bail out. Note that now cur points
|
|
* to last var in linked list */
|
|
break;
|
|
}
|
|
cur = cur->next;
|
|
continue;
|
|
}
|
|
/* We found an existing var with this name */
|
|
*value = '\0';
|
|
if (cur->flg_read_only) {
|
|
bb_error_msg("%s: readonly variable", str);
|
|
free(str);
|
|
return -1;
|
|
}
|
|
unsetenv(str); /* just in case */
|
|
*value = '=';
|
|
if (strcmp(cur->varstr, str) == 0) {
|
|
free_and_exp:
|
|
free(str);
|
|
goto exp;
|
|
}
|
|
if (cur->max_len >= strlen(str)) {
|
|
/* This one is from startup env, reuse space */
|
|
strcpy(cur->varstr, str);
|
|
goto free_and_exp;
|
|
}
|
|
/* max_len == 0 signifies "malloced" var, which we can
|
|
* (and has to) free */
|
|
if (!cur->max_len)
|
|
free(cur->varstr);
|
|
cur->max_len = 0;
|
|
goto set_str_and_exp;
|
|
}
|
|
|
|
/* Not found - create next variable struct */
|
|
cur->next = xzalloc(sizeof(*cur));
|
|
cur = cur->next;
|
|
|
|
set_str_and_exp:
|
|
cur->varstr = str;
|
|
exp:
|
|
if (flg_export)
|
|
cur->flg_export = 1;
|
|
if (cur->flg_export)
|
|
return putenv(cur->varstr);
|
|
return 0;
|
|
}
|
|
|
|
static void unset_local_var(const char *name)
|
|
{
|
|
struct variable *cur;
|
|
struct variable *prev = prev; /* for gcc */
|
|
int name_len;
|
|
|
|
if (!name)
|
|
return;
|
|
name_len = strlen(name);
|
|
cur = top_var;
|
|
while (cur) {
|
|
if (strncmp(cur->varstr, name, name_len) == 0 && cur->varstr[name_len] == '=') {
|
|
if (cur->flg_read_only) {
|
|
bb_error_msg("%s: readonly variable", name);
|
|
return;
|
|
}
|
|
/* prev is ok to use here because 1st variable, HUSH_VERSION,
|
|
* is ro, and we cannot reach this code on the 1st pass */
|
|
prev->next = cur->next;
|
|
unsetenv(cur->varstr);
|
|
if (!cur->max_len)
|
|
free(cur->varstr);
|
|
free(cur);
|
|
return;
|
|
}
|
|
prev = cur;
|
|
cur = cur->next;
|
|
}
|
|
}
|
|
|
|
static int is_assignment(const char *s)
|
|
{
|
|
if (!s || !isalpha(*s))
|
|
return 0;
|
|
s++;
|
|
while (isalnum(*s) || *s == '_')
|
|
s++;
|
|
return *s == '=';
|
|
}
|
|
|
|
/* the src parameter allows us to peek forward to a possible &n syntax
|
|
* for file descriptor duplication, e.g., "2>&1".
|
|
* Return code is 0 normally, 1 if a syntax error is detected in src.
|
|
* Resource errors (in xmalloc) cause the process to exit */
|
|
static int setup_redirect(struct p_context *ctx, int fd, redir_type style,
|
|
struct in_str *input)
|
|
{
|
|
struct child_prog *child = ctx->child;
|
|
struct redir_struct *redir = child->redirects;
|
|
struct redir_struct *last_redir = NULL;
|
|
|
|
/* Create a new redir_struct and drop it onto the end of the linked list */
|
|
while (redir) {
|
|
last_redir = redir;
|
|
redir = redir->next;
|
|
}
|
|
redir = xmalloc(sizeof(struct redir_struct));
|
|
redir->next = NULL;
|
|
redir->word.gl_pathv = NULL;
|
|
if (last_redir) {
|
|
last_redir->next = redir;
|
|
} else {
|
|
child->redirects = redir;
|
|
}
|
|
|
|
redir->type = style;
|
|
redir->fd = (fd == -1) ? redir_table[style].default_fd : fd;
|
|
|
|
debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip);
|
|
|
|
/* Check for a '2>&1' type redirect */
|
|
redir->dup = redirect_dup_num(input);
|
|
if (redir->dup == -2) return 1; /* syntax error */
|
|
if (redir->dup != -1) {
|
|
/* Erik had a check here that the file descriptor in question
|
|
* is legit; I postpone that to "run time"
|
|
* A "-" representation of "close me" shows up as a -3 here */
|
|
debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup);
|
|
} else {
|
|
/* We do _not_ try to open the file that src points to,
|
|
* since we need to return and let src be expanded first.
|
|
* Set ctx->pending_redirect, so we know what to do at the
|
|
* end of the next parsed word. */
|
|
ctx->pending_redirect = redir;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static struct pipe *new_pipe(void)
|
|
{
|
|
struct pipe *pi;
|
|
pi = xzalloc(sizeof(struct pipe));
|
|
/*pi->num_progs = 0;*/
|
|
/*pi->progs = NULL;*/
|
|
/*pi->next = NULL;*/
|
|
/*pi->followup = 0; invalid */
|
|
if (RES_NONE)
|
|
pi->res_word = RES_NONE;
|
|
return pi;
|
|
}
|
|
|
|
static void initialize_context(struct p_context *ctx)
|
|
{
|
|
ctx->child = NULL;
|
|
ctx->pipe = ctx->list_head = new_pipe();
|
|
ctx->pending_redirect = NULL;
|
|
ctx->res_w = RES_NONE;
|
|
//only ctx->parse_type is not touched... is this intentional?
|
|
ctx->old_flag = 0;
|
|
ctx->stack = NULL;
|
|
done_command(ctx); /* creates the memory for working child */
|
|
}
|
|
|
|
/* normal return is 0
|
|
* if a reserved word is found, and processed, return 1
|
|
* should handle if, then, elif, else, fi, for, while, until, do, done.
|
|
* case, function, and select are obnoxious, save those for later.
|
|
*/
|
|
#if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS
|
|
static int reserved_word(o_string *dest, struct p_context *ctx)
|
|
{
|
|
struct reserved_combo {
|
|
char literal[7];
|
|
unsigned char code;
|
|
int flag;
|
|
};
|
|
/* Mostly a list of accepted follow-up reserved words.
|
|
* FLAG_END means we are done with the sequence, and are ready
|
|
* to turn the compound list into a command.
|
|
* FLAG_START means the word must start a new compound list.
|
|
*/
|
|
static const struct reserved_combo reserved_list[] = {
|
|
#if ENABLE_HUSH_IF
|
|
{ "if", RES_IF, FLAG_THEN | FLAG_START },
|
|
{ "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
|
|
{ "elif", RES_ELIF, FLAG_THEN },
|
|
{ "else", RES_ELSE, FLAG_FI },
|
|
{ "fi", RES_FI, FLAG_END },
|
|
#endif
|
|
#if ENABLE_HUSH_LOOPS
|
|
{ "for", RES_FOR, FLAG_IN | FLAG_START },
|
|
{ "while", RES_WHILE, FLAG_DO | FLAG_START },
|
|
{ "until", RES_UNTIL, FLAG_DO | FLAG_START },
|
|
{ "in", RES_IN, FLAG_DO },
|
|
{ "do", RES_DO, FLAG_DONE },
|
|
{ "done", RES_DONE, FLAG_END }
|
|
#endif
|
|
};
|
|
|
|
const struct reserved_combo *r;
|
|
|
|
for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) {
|
|
if (strcmp(dest->data, r->literal) != 0)
|
|
continue;
|
|
debug_printf("found reserved word %s, code %d\n", r->literal, r->code);
|
|
if (r->flag & FLAG_START) {
|
|
struct p_context *new;
|
|
debug_printf("push stack\n");
|
|
#if ENABLE_HUSH_LOOPS
|
|
if (ctx->res_w == RES_IN || ctx->res_w == RES_FOR) {
|
|
syntax("malformed for"); /* example: 'for if' */
|
|
ctx->res_w = RES_SNTX;
|
|
b_reset(dest);
|
|
return 1;
|
|
}
|
|
#endif
|
|
new = xmalloc(sizeof(*new));
|
|
*new = *ctx; /* physical copy */
|
|
initialize_context(ctx);
|
|
ctx->stack = new;
|
|
} else if (ctx->res_w == RES_NONE || !(ctx->old_flag & (1 << r->code))) {
|
|
syntax(NULL);
|
|
ctx->res_w = RES_SNTX;
|
|
b_reset(dest);
|
|
return 1;
|
|
}
|
|
ctx->res_w = r->code;
|
|
ctx->old_flag = r->flag;
|
|
if (ctx->old_flag & FLAG_END) {
|
|
struct p_context *old;
|
|
debug_printf("pop stack\n");
|
|
done_pipe(ctx, PIPE_SEQ);
|
|
old = ctx->stack;
|
|
old->child->group = ctx->list_head;
|
|
old->child->subshell = 0;
|
|
*ctx = *old; /* physical copy */
|
|
free(old);
|
|
}
|
|
b_reset(dest);
|
|
return 1;
|
|
}
|
|
return 0;
|
|
}
|
|
#else
|
|
#define reserved_word(dest, ctx) ((int)0)
|
|
#endif
|
|
|
|
/* Normal return is 0.
|
|
* Syntax or xglob errors return 1. */
|
|
static int done_word(o_string *dest, struct p_context *ctx)
|
|
{
|
|
struct child_prog *child = ctx->child;
|
|
glob_t *glob_target;
|
|
int gr, flags = 0;
|
|
|
|
debug_printf_parse("done_word entered: '%s' %p\n", dest->data, child);
|
|
if (dest->length == 0 && !dest->nonnull) {
|
|
debug_printf_parse("done_word return 0: true null, ignored\n");
|
|
return 0;
|
|
}
|
|
if (ctx->pending_redirect) {
|
|
glob_target = &ctx->pending_redirect->word;
|
|
} else {
|
|
if (child->group) {
|
|
syntax(NULL);
|
|
debug_printf_parse("done_word return 1: syntax error, groups and arglists don't mix\n");
|
|
return 1;
|
|
}
|
|
if (!child->argv && (ctx->parse_type & PARSEFLAG_SEMICOLON)) {
|
|
debug_printf_parse(": checking '%s' for reserved-ness\n", dest->data);
|
|
if (reserved_word(dest, ctx)) {
|
|
debug_printf_parse("done_word return %d\n", (ctx->res_w == RES_SNTX));
|
|
return (ctx->res_w == RES_SNTX);
|
|
}
|
|
}
|
|
glob_target = &child->glob_result;
|
|
if (child->argv)
|
|
flags |= GLOB_APPEND;
|
|
}
|
|
gr = xglob(dest, flags, glob_target);
|
|
if (gr != 0) {
|
|
debug_printf_parse("done_word return 1: xglob returned %d\n", gr);
|
|
return 1;
|
|
}
|
|
|
|
b_reset(dest);
|
|
if (ctx->pending_redirect) {
|
|
ctx->pending_redirect = NULL;
|
|
if (glob_target->gl_pathc != 1) {
|
|
bb_error_msg("ambiguous redirect");
|
|
debug_printf_parse("done_word return 1: ambiguous redirect\n");
|
|
return 1;
|
|
}
|
|
} else {
|
|
child->argv = glob_target->gl_pathv;
|
|
}
|
|
#if ENABLE_HUSH_LOOPS
|
|
if (ctx->res_w == RES_FOR) {
|
|
done_word(dest, ctx);
|
|
done_pipe(ctx, PIPE_SEQ);
|
|
}
|
|
#endif
|
|
debug_printf_parse("done_word return 0\n");
|
|
return 0;
|
|
}
|
|
|
|
/* The only possible error here is out of memory, in which case
|
|
* xmalloc exits. */
|
|
static int done_command(struct p_context *ctx)
|
|
{
|
|
/* The child is really already in the pipe structure, so
|
|
* advance the pipe counter and make a new, null child. */
|
|
struct pipe *pi = ctx->pipe;
|
|
struct child_prog *child = ctx->child;
|
|
|
|
if (child) {
|
|
if (child->group == NULL
|
|
&& child->argv == NULL
|
|
&& child->redirects == NULL
|
|
) {
|
|
debug_printf_parse("done_command: skipping null cmd, num_progs=%d\n", pi->num_progs);
|
|
return pi->num_progs;
|
|
}
|
|
pi->num_progs++;
|
|
debug_printf_parse("done_command: ++num_progs=%d\n", pi->num_progs);
|
|
} else {
|
|
debug_printf_parse("done_command: initializing, num_progs=%d\n", pi->num_progs);
|
|
}
|
|
|
|
/* Only real trickiness here is that the uncommitted
|
|
* child structure is not counted in pi->num_progs. */
|
|
pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
|
|
child = &pi->progs[pi->num_progs];
|
|
|
|
memset(child, 0, sizeof(*child));
|
|
/*child->redirects = NULL;*/
|
|
/*child->argv = NULL;*/
|
|
/*child->is_stopped = 0;*/
|
|
/*child->group = NULL;*/
|
|
/*child->glob_result.gl_pathv = NULL;*/
|
|
child->family = pi;
|
|
//sp: /*child->sp = 0;*/
|
|
//pt: child->parse_type = ctx->parse_type;
|
|
|
|
ctx->child = child;
|
|
/* but ctx->pipe and ctx->list_head remain unchanged */
|
|
|
|
return pi->num_progs; /* used only for 0/nonzero check */
|
|
}
|
|
|
|
static int done_pipe(struct p_context *ctx, pipe_style type)
|
|
{
|
|
struct pipe *new_p;
|
|
int not_null;
|
|
|
|
debug_printf_parse("done_pipe entered, followup %d\n", type);
|
|
not_null = done_command(ctx); /* implicit closure of previous command */
|
|
ctx->pipe->followup = type;
|
|
ctx->pipe->res_word = ctx->res_w;
|
|
/* Without this check, even just <enter> on command line generates
|
|
* tree of three NOPs (!). Which is harmless but annoying.
|
|
* IOW: it is safe to do it unconditionally. */
|
|
if (not_null) {
|
|
new_p = new_pipe();
|
|
ctx->pipe->next = new_p;
|
|
ctx->pipe = new_p;
|
|
ctx->child = NULL;
|
|
done_command(ctx); /* set up new pipe to accept commands */
|
|
}
|
|
debug_printf_parse("done_pipe return 0\n");
|
|
return 0;
|
|
}
|
|
|
|
/* peek ahead in the in_str to find out if we have a "&n" construct,
|
|
* as in "2>&1", that represents duplicating a file descriptor.
|
|
* returns either -2 (syntax error), -1 (no &), or the number found.
|
|
*/
|
|
static int redirect_dup_num(struct in_str *input)
|
|
{
|
|
int ch, d = 0, ok = 0;
|
|
ch = b_peek(input);
|
|
if (ch != '&') return -1;
|
|
|
|
b_getch(input); /* get the & */
|
|
ch = b_peek(input);
|
|
if (ch == '-') {
|
|
b_getch(input);
|
|
return -3; /* "-" represents "close me" */
|
|
}
|
|
while (isdigit(ch)) {
|
|
d = d*10 + (ch-'0');
|
|
ok = 1;
|
|
b_getch(input);
|
|
ch = b_peek(input);
|
|
}
|
|
if (ok) return d;
|
|
|
|
bb_error_msg("ambiguous redirect");
|
|
return -2;
|
|
}
|
|
|
|
/* If a redirect is immediately preceded by a number, that number is
|
|
* supposed to tell which file descriptor to redirect. This routine
|
|
* looks for such preceding numbers. In an ideal world this routine
|
|
* needs to handle all the following classes of redirects...
|
|
* echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
|
|
* echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
|
|
* echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
|
|
* echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
|
|
* A -1 output from this program means no valid number was found, so the
|
|
* caller should use the appropriate default for this redirection.
|
|
*/
|
|
static int redirect_opt_num(o_string *o)
|
|
{
|
|
int num;
|
|
|
|
if (o->length == 0)
|
|
return -1;
|
|
for (num = 0; num < o->length; num++) {
|
|
if (!isdigit(*(o->data + num))) {
|
|
return -1;
|
|
}
|
|
}
|
|
/* reuse num (and save an int) */
|
|
num = atoi(o->data);
|
|
b_reset(o);
|
|
return num;
|
|
}
|
|
|
|
#if ENABLE_HUSH_TICK
|
|
static FILE *generate_stream_from_list(struct pipe *head)
|
|
{
|
|
FILE *pf;
|
|
int pid, channel[2];
|
|
|
|
xpipe(channel);
|
|
#if BB_MMU
|
|
pid = fork();
|
|
#else
|
|
pid = vfork();
|
|
#endif
|
|
if (pid < 0) {
|
|
bb_perror_msg_and_die("fork");
|
|
} else if (pid == 0) {
|
|
close(channel[0]);
|
|
if (channel[1] != 1) {
|
|
dup2(channel[1], 1);
|
|
close(channel[1]);
|
|
}
|
|
/* Prevent it from trying to handle ctrl-z etc */
|
|
#if ENABLE_HUSH_JOB
|
|
run_list_level = 1;
|
|
#endif
|
|
/* Process substitution is not considered to be usual
|
|
* 'command execution'.
|
|
* SUSv3 says ctrl-Z should be ignored, ctrl-C should not. */
|
|
/* Not needed, we are relying on it being disabled
|
|
* everywhere outside actual command execution. */
|
|
/*set_jobctrl_sighandler(SIG_IGN);*/
|
|
set_misc_sighandler(SIG_DFL);
|
|
_exit(run_list_real(head)); /* leaks memory */
|
|
}
|
|
close(channel[1]);
|
|
pf = fdopen(channel[0], "r");
|
|
return pf;
|
|
}
|
|
|
|
/* Return code is exit status of the process that is run. */
|
|
static int process_command_subs(o_string *dest, struct p_context *ctx,
|
|
struct in_str *input, const char *subst_end)
|
|
{
|
|
int retcode, ch, eol_cnt;
|
|
o_string result = NULL_O_STRING;
|
|
struct p_context inner;
|
|
FILE *p;
|
|
struct in_str pipe_str;
|
|
|
|
initialize_context(&inner);
|
|
|
|
/* recursion to generate command */
|
|
retcode = parse_stream(&result, &inner, input, subst_end);
|
|
if (retcode != 0)
|
|
return retcode; /* syntax error or EOF */
|
|
done_word(&result, &inner);
|
|
done_pipe(&inner, PIPE_SEQ);
|
|
b_free(&result);
|
|
|
|
p = generate_stream_from_list(inner.list_head);
|
|
if (p == NULL) return 1;
|
|
mark_open(fileno(p));
|
|
setup_file_in_str(&pipe_str, p);
|
|
|
|
/* now send results of command back into original context */
|
|
eol_cnt = 0;
|
|
while ((ch = b_getch(&pipe_str)) != EOF) {
|
|
if (ch == '\n') {
|
|
eol_cnt++;
|
|
continue;
|
|
}
|
|
while (eol_cnt) {
|
|
b_addqchr(dest, '\n', dest->quote);
|
|
eol_cnt--;
|
|
}
|
|
b_addqchr(dest, ch, dest->quote);
|
|
}
|
|
|
|
debug_printf("done reading from pipe, pclose()ing\n");
|
|
/* This is the step that wait()s for the child. Should be pretty
|
|
* safe, since we just read an EOF from its stdout. We could try
|
|
* to do better, by using wait(), and keeping track of background jobs
|
|
* at the same time. That would be a lot of work, and contrary
|
|
* to the KISS philosophy of this program. */
|
|
mark_closed(fileno(p));
|
|
retcode = fclose(p);
|
|
free_pipe_list(inner.list_head, 0);
|
|
debug_printf("closed FILE from child, retcode=%d\n", retcode);
|
|
return retcode;
|
|
}
|
|
#endif
|
|
|
|
static int parse_group(o_string *dest, struct p_context *ctx,
|
|
struct in_str *input, int ch)
|
|
{
|
|
int rcode;
|
|
const char *endch = NULL;
|
|
struct p_context sub;
|
|
struct child_prog *child = ctx->child;
|
|
|
|
debug_printf_parse("parse_group entered\n");
|
|
if (child->argv) {
|
|
syntax(NULL);
|
|
debug_printf_parse("parse_group return 1: syntax error, groups and arglists don't mix\n");
|
|
return 1;
|
|
}
|
|
initialize_context(&sub);
|
|
endch = "}";
|
|
if (ch == '(') {
|
|
endch = ")";
|
|
child->subshell = 1;
|
|
}
|
|
rcode = parse_stream(dest, &sub, input, endch);
|
|
//vda: err chk?
|
|
done_word(dest, &sub); /* finish off the final word in the subcontext */
|
|
done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */
|
|
child->group = sub.list_head;
|
|
|
|
debug_printf_parse("parse_group return %d\n", rcode);
|
|
return rcode;
|
|
/* child remains "open", available for possible redirects */
|
|
}
|
|
|
|
/* Basically useful version until someone wants to get fancier,
|
|
* see the bash man page under "Parameter Expansion" */
|
|
static const char *lookup_param(const char *src)
|
|
{
|
|
struct variable *var = get_local_var(src);
|
|
if (var)
|
|
return strchr(var->varstr, '=') + 1;
|
|
return NULL;
|
|
}
|
|
|
|
/* return code: 0 for OK, 1 for syntax error */
|
|
static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input)
|
|
{
|
|
int ch = b_peek(input); /* first character after the $ */
|
|
unsigned char quote_mask = dest->quote ? 0x80 : 0;
|
|
|
|
debug_printf_parse("handle_dollar entered: ch='%c'\n", ch);
|
|
if (isalpha(ch)) {
|
|
b_addchr(dest, SPECIAL_VAR_SYMBOL);
|
|
//sp: ctx->child->sp++;
|
|
while (1) {
|
|
debug_printf_parse(": '%c'\n", ch);
|
|
b_getch(input);
|
|
b_addchr(dest, ch | quote_mask);
|
|
quote_mask = 0;
|
|
ch = b_peek(input);
|
|
if (!isalnum(ch) && ch != '_')
|
|
break;
|
|
}
|
|
b_addchr(dest, SPECIAL_VAR_SYMBOL);
|
|
} else if (isdigit(ch)) {
|
|
make_one_char_var:
|
|
b_addchr(dest, SPECIAL_VAR_SYMBOL);
|
|
//sp: ctx->child->sp++;
|
|
debug_printf_parse(": '%c'\n", ch);
|
|
b_getch(input);
|
|
b_addchr(dest, ch | quote_mask);
|
|
b_addchr(dest, SPECIAL_VAR_SYMBOL);
|
|
} else switch (ch) {
|
|
case '$': /* pid */
|
|
case '!': /* last bg pid */
|
|
case '?': /* last exit code */
|
|
case '#': /* number of args */
|
|
case '*': /* args */
|
|
case '@': /* args */
|
|
goto make_one_char_var;
|
|
case '{':
|
|
b_addchr(dest, SPECIAL_VAR_SYMBOL);
|
|
//sp: ctx->child->sp++;
|
|
b_getch(input);
|
|
/* XXX maybe someone will try to escape the '}' */
|
|
while (1) {
|
|
ch = b_getch(input);
|
|
if (ch == '}')
|
|
break;
|
|
if (!isalnum(ch) && ch != '_') {
|
|
syntax("unterminated ${name}");
|
|
debug_printf_parse("handle_dollar return 1: unterminated ${name}\n");
|
|
return 1;
|
|
}
|
|
debug_printf_parse(": '%c'\n", ch);
|
|
b_addchr(dest, ch | quote_mask);
|
|
quote_mask = 0;
|
|
}
|
|
b_addchr(dest, SPECIAL_VAR_SYMBOL);
|
|
break;
|
|
#if ENABLE_HUSH_TICK
|
|
case '(':
|
|
b_getch(input);
|
|
process_command_subs(dest, ctx, input, ")");
|
|
break;
|
|
#endif
|
|
case '-':
|
|
case '_':
|
|
/* still unhandled, but should be eventually */
|
|
bb_error_msg("unhandled syntax: $%c", ch);
|
|
return 1;
|
|
break;
|
|
default:
|
|
b_addqchr(dest, '$', dest->quote);
|
|
}
|
|
debug_printf_parse("handle_dollar return 0\n");
|
|
return 0;
|
|
}
|
|
|
|
/* return code is 0 for normal exit, 1 for syntax error */
|
|
static int parse_stream(o_string *dest, struct p_context *ctx,
|
|
struct in_str *input, const char *end_trigger)
|
|
{
|
|
int ch, m;
|
|
int redir_fd;
|
|
redir_type redir_style;
|
|
int next;
|
|
|
|
/* Only double-quote state is handled in the state variable dest->quote.
|
|
* A single-quote triggers a bypass of the main loop until its mate is
|
|
* found. When recursing, quote state is passed in via dest->quote. */
|
|
|
|
debug_printf_parse("parse_stream entered, end_trigger='%s'\n", end_trigger);
|
|
|
|
while (1) {
|
|
m = CHAR_IFS;
|
|
next = '\0';
|
|
ch = b_getch(input);
|
|
if (ch != EOF) {
|
|
m = charmap[ch];
|
|
if (ch != '\n')
|
|
next = b_peek(input);
|
|
}
|
|
debug_printf_parse(": ch=%c (%d) m=%d quote=%d\n",
|
|
ch, ch, m, dest->quote);
|
|
if (m == CHAR_ORDINARY
|
|
|| (m != CHAR_SPECIAL && dest->quote)
|
|
) {
|
|
if (ch == EOF) {
|
|
syntax("unterminated \"");
|
|
debug_printf_parse("parse_stream return 1: unterminated \"\n");
|
|
return 1;
|
|
}
|
|
b_addqchr(dest, ch, dest->quote);
|
|
continue;
|
|
}
|
|
if (m == CHAR_IFS) {
|
|
if (done_word(dest, ctx)) {
|
|
debug_printf_parse("parse_stream return 1: done_word!=0\n");
|
|
return 1;
|
|
}
|
|
if (ch == EOF)
|
|
break;
|
|
/* If we aren't performing a substitution, treat
|
|
* a newline as a command separator.
|
|
* [why we don't handle it exactly like ';'? --vda] */
|
|
if (end_trigger && ch == '\n') {
|
|
done_pipe(ctx, PIPE_SEQ);
|
|
}
|
|
}
|
|
if ((end_trigger && strchr(end_trigger, ch))
|
|
&& !dest->quote && ctx->res_w == RES_NONE
|
|
) {
|
|
debug_printf_parse("parse_stream return 0: end_trigger char found\n");
|
|
return 0;
|
|
}
|
|
if (m == CHAR_IFS)
|
|
continue;
|
|
switch (ch) {
|
|
case '#':
|
|
if (dest->length == 0 && !dest->quote) {
|
|
while (1) {
|
|
ch = b_peek(input);
|
|
if (ch == EOF || ch == '\n')
|
|
break;
|
|
b_getch(input);
|
|
}
|
|
} else {
|
|
b_addqchr(dest, ch, dest->quote);
|
|
}
|
|
break;
|
|
case '\\':
|
|
if (next == EOF) {
|
|
syntax("\\<eof>");
|
|
debug_printf_parse("parse_stream return 1: \\<eof>\n");
|
|
return 1;
|
|
}
|
|
b_addqchr(dest, '\\', dest->quote);
|
|
b_addqchr(dest, b_getch(input), dest->quote);
|
|
break;
|
|
case '$':
|
|
if (handle_dollar(dest, ctx, input) != 0) {
|
|
debug_printf_parse("parse_stream return 1: handle_dollar returned non-0\n");
|
|
return 1;
|
|
}
|
|
break;
|
|
case '\'':
|
|
dest->nonnull = 1;
|
|
while (1) {
|
|
ch = b_getch(input);
|
|
if (ch == EOF || ch == '\'')
|
|
break;
|
|
b_addchr(dest, ch);
|
|
}
|
|
if (ch == EOF) {
|
|
syntax("unterminated '");
|
|
debug_printf_parse("parse_stream return 1: unterminated '\n");
|
|
return 1;
|
|
}
|
|
break;
|
|
case '"':
|
|
dest->nonnull = 1;
|
|
dest->quote = !dest->quote;
|
|
break;
|
|
#if ENABLE_HUSH_TICK
|
|
case '`':
|
|
process_command_subs(dest, ctx, input, "`");
|
|
break;
|
|
#endif
|
|
case '>':
|
|
redir_fd = redirect_opt_num(dest);
|
|
done_word(dest, ctx);
|
|
redir_style = REDIRECT_OVERWRITE;
|
|
if (next == '>') {
|
|
redir_style = REDIRECT_APPEND;
|
|
b_getch(input);
|
|
}
|
|
#if 0
|
|
else if (next == '(') {
|
|
syntax(">(process) not supported");
|
|
debug_printf_parse("parse_stream return 1: >(process) not supported\n");
|
|
return 1;
|
|
}
|
|
#endif
|
|
setup_redirect(ctx, redir_fd, redir_style, input);
|
|
break;
|
|
case '<':
|
|
redir_fd = redirect_opt_num(dest);
|
|
done_word(dest, ctx);
|
|
redir_style = REDIRECT_INPUT;
|
|
if (next == '<') {
|
|
redir_style = REDIRECT_HEREIS;
|
|
b_getch(input);
|
|
} else if (next == '>') {
|
|
redir_style = REDIRECT_IO;
|
|
b_getch(input);
|
|
}
|
|
#if 0
|
|
else if (next == '(') {
|
|
syntax("<(process) not supported");
|
|
debug_printf_parse("parse_stream return 1: <(process) not supported\n");
|
|
return 1;
|
|
}
|
|
#endif
|
|
setup_redirect(ctx, redir_fd, redir_style, input);
|
|
break;
|
|
case ';':
|
|
done_word(dest, ctx);
|
|
done_pipe(ctx, PIPE_SEQ);
|
|
break;
|
|
case '&':
|
|
done_word(dest, ctx);
|
|
if (next == '&') {
|
|
b_getch(input);
|
|
done_pipe(ctx, PIPE_AND);
|
|
} else {
|
|
done_pipe(ctx, PIPE_BG);
|
|
}
|
|
break;
|
|
case '|':
|
|
done_word(dest, ctx);
|
|
if (next == '|') {
|
|
b_getch(input);
|
|
done_pipe(ctx, PIPE_OR);
|
|
} else {
|
|
/* we could pick up a file descriptor choice here
|
|
* with redirect_opt_num(), but bash doesn't do it.
|
|
* "echo foo 2| cat" yields "foo 2". */
|
|
done_command(ctx);
|
|
}
|
|
break;
|
|
case '(':
|
|
case '{':
|
|
if (parse_group(dest, ctx, input, ch) != 0) {
|
|
debug_printf_parse("parse_stream return 1: parse_group returned non-0\n");
|
|
return 1;
|
|
}
|
|
break;
|
|
case ')':
|
|
case '}':
|
|
syntax("unexpected }"); /* Proper use of this character is caught by end_trigger */
|
|
debug_printf_parse("parse_stream return 1: unexpected '}'\n");
|
|
return 1;
|
|
default:
|
|
if (ENABLE_HUSH_DEBUG)
|
|
bb_error_msg_and_die("BUG: unexpected %c\n", ch);
|
|
}
|
|
}
|
|
/* Complain if quote? No, maybe we just finished a command substitution
|
|
* that was quoted. Example:
|
|
* $ echo "`cat foo` plus more"
|
|
* and we just got the EOF generated by the subshell that ran "cat foo"
|
|
* The only real complaint is if we got an EOF when end_trigger != NULL,
|
|
* that is, we were really supposed to get end_trigger, and never got
|
|
* one before the EOF. Can't use the standard "syntax error" return code,
|
|
* so that parse_stream_outer can distinguish the EOF and exit smoothly. */
|
|
debug_printf_parse("parse_stream return %d\n", -(end_trigger != NULL));
|
|
if (end_trigger)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
static void set_in_charmap(const char *set, int code)
|
|
{
|
|
while (*set)
|
|
charmap[(unsigned char)*set++] = code;
|
|
}
|
|
|
|
static void update_charmap(void)
|
|
{
|
|
/* char *ifs and char charmap[256] are both globals. */
|
|
ifs = getenv("IFS");
|
|
if (ifs == NULL)
|
|
ifs = " \t\n";
|
|
/* Precompute a list of 'flow through' behavior so it can be treated
|
|
* quickly up front. Computation is necessary because of IFS.
|
|
* Special case handling of IFS == " \t\n" is not implemented.
|
|
* The charmap[] array only really needs two bits each,
|
|
* and on most machines that would be faster (reduced L1 cache use).
|
|
*/
|
|
memset(charmap, CHAR_ORDINARY, sizeof(charmap));
|
|
#if ENABLE_HUSH_TICK
|
|
set_in_charmap("\\$\"`", CHAR_SPECIAL);
|
|
#else
|
|
set_in_charmap("\\$\"", CHAR_SPECIAL);
|
|
#endif
|
|
set_in_charmap("<>;&|(){}#'", CHAR_ORDINARY_IF_QUOTED);
|
|
set_in_charmap(ifs, CHAR_IFS); /* are ordinary if quoted */
|
|
}
|
|
|
|
/* most recursion does not come through here, the exception is
|
|
* from builtin_source() and builtin_eval() */
|
|
static int parse_and_run_stream(struct in_str *inp, int parse_flag)
|
|
{
|
|
struct p_context ctx;
|
|
o_string temp = NULL_O_STRING;
|
|
int rcode;
|
|
do {
|
|
ctx.parse_type = parse_flag;
|
|
initialize_context(&ctx);
|
|
update_charmap();
|
|
if (!(parse_flag & PARSEFLAG_SEMICOLON) || (parse_flag & PARSEFLAG_REPARSING))
|
|
set_in_charmap(";$&|", CHAR_ORDINARY);
|
|
#if ENABLE_HUSH_INTERACTIVE
|
|
inp->promptmode = 0; /* PS1 */
|
|
#endif
|
|
/* We will stop & execute after each ';' or '\n'.
|
|
* Example: "sleep 9999; echo TEST" + ctrl-C:
|
|
* TEST should be printed */
|
|
rcode = parse_stream(&temp, &ctx, inp, ";\n");
|
|
if (rcode != 1 && ctx.old_flag != 0) {
|
|
syntax(NULL);
|
|
}
|
|
if (rcode != 1 && ctx.old_flag == 0) {
|
|
done_word(&temp, &ctx);
|
|
done_pipe(&ctx, PIPE_SEQ);
|
|
debug_print_tree(ctx.list_head, 0);
|
|
debug_printf_exec("parse_stream_outer: run_list\n");
|
|
run_list(ctx.list_head);
|
|
} else {
|
|
if (ctx.old_flag != 0) {
|
|
free(ctx.stack);
|
|
b_reset(&temp);
|
|
}
|
|
temp.nonnull = 0;
|
|
temp.quote = 0;
|
|
inp->p = NULL;
|
|
free_pipe_list(ctx.list_head, 0);
|
|
}
|
|
b_free(&temp);
|
|
} while (rcode != -1 && !(parse_flag & PARSEFLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
|
|
return 0;
|
|
}
|
|
|
|
static int parse_and_run_string(const char *s, int parse_flag)
|
|
{
|
|
struct in_str input;
|
|
setup_string_in_str(&input, s);
|
|
return parse_and_run_stream(&input, parse_flag);
|
|
}
|
|
|
|
static int parse_and_run_file(FILE *f)
|
|
{
|
|
int rcode;
|
|
struct in_str input;
|
|
setup_file_in_str(&input, f);
|
|
rcode = parse_and_run_stream(&input, PARSEFLAG_SEMICOLON);
|
|
return rcode;
|
|
}
|
|
|
|
#if ENABLE_HUSH_JOB
|
|
/* Make sure we have a controlling tty. If we get started under a job
|
|
* aware app (like bash for example), make sure we are now in charge so
|
|
* we don't fight over who gets the foreground */
|
|
static void setup_job_control(void)
|
|
{
|
|
pid_t shell_pgrp;
|
|
|
|
saved_task_pgrp = shell_pgrp = getpgrp();
|
|
debug_printf_jobs("saved_task_pgrp=%d\n", saved_task_pgrp);
|
|
fcntl(interactive_fd, F_SETFD, FD_CLOEXEC);
|
|
|
|
/* If we were ran as 'hush &',
|
|
* sleep until we are in the foreground. */
|
|
while (tcgetpgrp(interactive_fd) != shell_pgrp) {
|
|
/* Send TTIN to ourself (should stop us) */
|
|
kill(- shell_pgrp, SIGTTIN);
|
|
shell_pgrp = getpgrp();
|
|
}
|
|
|
|
/* Ignore job-control and misc signals. */
|
|
set_jobctrl_sighandler(SIG_IGN);
|
|
set_misc_sighandler(SIG_IGN);
|
|
//huh? signal(SIGCHLD, SIG_IGN);
|
|
|
|
/* We _must_ restore tty pgrp on fatal signals */
|
|
set_fatal_sighandler(sigexit);
|
|
|
|
/* Put ourselves in our own process group. */
|
|
setpgrp(); /* is the same as setpgid(our_pid, our_pid); */
|
|
/* Grab control of the terminal. */
|
|
tcsetpgrp(interactive_fd, getpid());
|
|
}
|
|
#endif
|
|
|
|
int hush_main(int argc, char **argv);
|
|
int hush_main(int argc, char **argv)
|
|
{
|
|
static const char version_str[] = "HUSH_VERSION="HUSH_VER_STR;
|
|
static const struct variable const_shell_ver = {
|
|
.next = NULL,
|
|
.varstr = (char*)version_str,
|
|
.max_len = 1, /* 0 can provoke free(name) */
|
|
.flg_export = 1,
|
|
.flg_read_only = 1,
|
|
};
|
|
|
|
int opt;
|
|
FILE *input;
|
|
char **e;
|
|
struct variable *cur_var;
|
|
|
|
PTR_TO_GLOBALS = xzalloc(sizeof(G));
|
|
|
|
/* Deal with HUSH_VERSION */
|
|
shell_ver = const_shell_ver; /* copying struct here */
|
|
top_var = &shell_ver;
|
|
unsetenv("HUSH_VERSION"); /* in case it exists in initial env */
|
|
/* Initialize our shell local variables with the values
|
|
* currently living in the environment */
|
|
cur_var = top_var;
|
|
e = environ;
|
|
if (e) while (*e) {
|
|
char *value = strchr(*e, '=');
|
|
if (value) { /* paranoia */
|
|
cur_var->next = xzalloc(sizeof(*cur_var));
|
|
cur_var = cur_var->next;
|
|
cur_var->varstr = *e;
|
|
cur_var->max_len = strlen(*e);
|
|
cur_var->flg_export = 1;
|
|
}
|
|
e++;
|
|
}
|
|
putenv((char *)version_str); /* reinstate HUSH_VERSION */
|
|
|
|
#if ENABLE_FEATURE_EDITING
|
|
line_input_state = new_line_input_t(FOR_SHELL);
|
|
#endif
|
|
/* XXX what should these be while sourcing /etc/profile? */
|
|
global_argc = argc;
|
|
global_argv = argv;
|
|
/* Initialize some more globals to non-zero values */
|
|
set_cwd();
|
|
#if ENABLE_HUSH_INTERACTIVE
|
|
#if ENABLE_FEATURE_EDITING
|
|
cmdedit_set_initial_prompt();
|
|
#endif
|
|
PS2 = "> ";
|
|
#endif
|
|
|
|
if (EXIT_SUCCESS) /* otherwise is already done */
|
|
last_return_code = EXIT_SUCCESS;
|
|
|
|
if (argv[0] && argv[0][0] == '-') {
|
|
debug_printf("sourcing /etc/profile\n");
|
|
input = fopen("/etc/profile", "r");
|
|
if (input != NULL) {
|
|
mark_open(fileno(input));
|
|
parse_and_run_file(input);
|
|
mark_closed(fileno(input));
|
|
fclose(input);
|
|
}
|
|
}
|
|
input = stdin;
|
|
|
|
while ((opt = getopt(argc, argv, "c:xif")) > 0) {
|
|
switch (opt) {
|
|
case 'c':
|
|
global_argv = argv + optind;
|
|
global_argc = argc - optind;
|
|
opt = parse_and_run_string(optarg, PARSEFLAG_SEMICOLON);
|
|
goto final_return;
|
|
case 'i':
|
|
/* Well, we cannot just declare interactiveness,
|
|
* we have to have some stuff (ctty, etc) */
|
|
/* interactive_fd++; */
|
|
break;
|
|
case 'f':
|
|
fake_mode = 1;
|
|
break;
|
|
default:
|
|
#ifndef BB_VER
|
|
fprintf(stderr, "Usage: sh [FILE]...\n"
|
|
" or: sh -c command [args]...\n\n");
|
|
exit(EXIT_FAILURE);
|
|
#else
|
|
bb_show_usage();
|
|
#endif
|
|
}
|
|
}
|
|
#if ENABLE_HUSH_JOB
|
|
/* A shell is interactive if the '-i' flag was given, or if all of
|
|
* the following conditions are met:
|
|
* no -c command
|
|
* no arguments remaining or the -s flag given
|
|
* standard input is a terminal
|
|
* standard output is a terminal
|
|
* Refer to Posix.2, the description of the 'sh' utility. */
|
|
if (argv[optind] == NULL && input == stdin
|
|
&& isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)
|
|
) {
|
|
saved_tty_pgrp = tcgetpgrp(STDIN_FILENO);
|
|
debug_printf("saved_tty_pgrp=%d\n", saved_tty_pgrp);
|
|
if (saved_tty_pgrp >= 0) {
|
|
/* try to dup to high fd#, >= 255 */
|
|
interactive_fd = fcntl(STDIN_FILENO, F_DUPFD, 255);
|
|
if (interactive_fd < 0) {
|
|
/* try to dup to any fd */
|
|
interactive_fd = dup(STDIN_FILENO);
|
|
if (interactive_fd < 0)
|
|
/* give up */
|
|
interactive_fd = 0;
|
|
}
|
|
// TODO: track & disallow any attempts of user
|
|
// to (inadvertently) close/redirect it
|
|
}
|
|
}
|
|
debug_printf("interactive_fd=%d\n", interactive_fd);
|
|
if (interactive_fd) {
|
|
/* Looks like they want an interactive shell */
|
|
setup_job_control();
|
|
/* Make xfuncs do cleanup on exit */
|
|
die_sleep = -1; /* flag */
|
|
// FIXME: should we reset die_sleep = 0 whereever we fork?
|
|
if (setjmp(die_jmp)) {
|
|
/* xfunc has failed! die die die */
|
|
hush_exit(xfunc_error_retval);
|
|
}
|
|
#if !ENABLE_FEATURE_SH_EXTRA_QUIET
|
|
printf("\n\n%s hush - the humble shell v"HUSH_VER_STR"\n", bb_banner);
|
|
printf("Enter 'help' for a list of built-in commands.\n\n");
|
|
#endif
|
|
}
|
|
#elif ENABLE_HUSH_INTERACTIVE
|
|
/* no job control compiled, only prompt/line editing */
|
|
if (argv[optind] == NULL && input == stdin
|
|
&& isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)
|
|
) {
|
|
interactive_fd = fcntl(STDIN_FILENO, F_DUPFD, 255);
|
|
if (interactive_fd < 0) {
|
|
/* try to dup to any fd */
|
|
interactive_fd = dup(STDIN_FILENO);
|
|
if (interactive_fd < 0)
|
|
/* give up */
|
|
interactive_fd = 0;
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
if (argv[optind] == NULL) {
|
|
opt = parse_and_run_file(stdin);
|
|
goto final_return;
|
|
}
|
|
|
|
debug_printf("\nrunning script '%s'\n", argv[optind]);
|
|
global_argv = argv + optind;
|
|
global_argc = argc - optind;
|
|
input = xfopen(argv[optind], "r");
|
|
opt = parse_and_run_file(input);
|
|
|
|
final_return:
|
|
|
|
#if ENABLE_FEATURE_CLEAN_UP
|
|
fclose(input);
|
|
if (cwd != bb_msg_unknown)
|
|
free((char*)cwd);
|
|
cur_var = top_var->next;
|
|
while (cur_var) {
|
|
struct variable *tmp = cur_var;
|
|
if (!cur_var->max_len)
|
|
free(cur_var->varstr);
|
|
cur_var = cur_var->next;
|
|
free(tmp);
|
|
}
|
|
#endif
|
|
hush_exit(opt ? opt : last_return_code);
|
|
}
|