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hush: do "struct globals" trick. hush.o data+bss = 0 bytes now.

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+60 bytes to image, but -8000 bytes in bss.
This commit is contained in:
Denis Vlasenko 2007-05-17 15:38:46 +00:00
parent b6a741ffa7
commit c8be5ee325
1 changed files with 135 additions and 106 deletions
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241
shell/hush.c
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@ -81,6 +81,7 @@
#include <glob.h> /* glob, of course */
#include <getopt.h> /* should be pretty obvious */
/* #include <dmalloc.h> */
extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
/* If you comment out one of these below, it will be #defined later
@ -273,49 +274,6 @@ struct variables {
int flg_read_only;
};
/* globals, connect us to the outside world
* the first three support $?, $#, and $1 */
static char **global_argv;
static int global_argc;
static int last_return_code;
extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */
/* "globals" within this file */
enum {
CHAR_ORDINARY = 0,
CHAR_ORDINARY_IF_QUOTED = 1, /* example: *, # */
CHAR_IFS = 2, /* treated as ordinary if quoted */
CHAR_SPECIAL = 3, /* example: $ */
};
static unsigned char charmap[256];
static const char *ifs;
static int fake_mode;
static struct close_me *close_me_head;
static const char *cwd;
static unsigned last_bg_pid;
#if !ENABLE_HUSH_INTERACTIVE
enum { interactive_fd = 0 };
#else
/* 'interactive_fd' is a fd# open to ctty, if we have one
* _AND_ if we decided to act interactively */
static int interactive_fd;
#if ENABLE_HUSH_JOB
static pid_t saved_task_pgrp;
static pid_t saved_tty_pgrp;
static int last_jobid;
static struct pipe *job_list;
#endif
static const char *PS1;
static const char *PS2;
#endif
#define HUSH_VER_STR "0.02"
static struct variables shell_ver = { NULL, "HUSH_VERSION", HUSH_VER_STR, 1, 1 };
static struct variables *top_vars = &shell_ver;
#define B_CHUNK 100
#define B_NOSPAC 1
typedef struct {
char *data;
int length;
@ -324,8 +282,7 @@ typedef struct {
int nonnull;
} o_string;
#define NULL_O_STRING {NULL,0,0,0,0}
/* used for initialization:
o_string foo = NULL_O_STRING; */
/* used for initialization: o_string foo = NULL_O_STRING; */
/* I can almost use ordinary FILE *. Is open_memstream() universally
* available? Where is it documented? */
@ -345,14 +302,114 @@ struct in_str {
#define b_getch(input) ((input)->get(input))
#define b_peek(input) ((input)->peek(input))
#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
struct built_in_command {
const char *cmd; /* name */
const char *descr; /* description */
int (*function) (char **argv); /* function ptr */
enum {
CHAR_ORDINARY = 0,
CHAR_ORDINARY_IF_QUOTED = 1, /* example: *, # */
CHAR_IFS = 2, /* treated as ordinary if quoted */
CHAR_SPECIAL = 3, /* example: $ */
};
/* "Globals" within this file */
#define HUSH_VER_STR "0.02"
static const struct variables const_shell_ver = {
NULL, "HUSH_VERSION", HUSH_VER_STR, 1, 1
};
/* Sorted roughly by size (smaller offsets == smaller code) */
struct globals {
#if ENABLE_HUSH_INTERACTIVE
/* 'interactive_fd' is a fd# open to ctty, if we have one
* _AND_ if we decided to act interactively */
int interactive_fd;
const char *PS1;
const char *PS2;
#endif
#if ENABLE_FEATURE_EDITING
line_input_t *line_input_state;
#endif
#if ENABLE_HUSH_JOB
int run_list_level;
pid_t saved_task_pgrp;
pid_t saved_tty_pgrp;
int last_jobid;
struct pipe *job_list;
struct pipe *toplevel_list;
smallint ctrl_z_flag;
#endif
smallint fake_mode;
/* these three support $?, $#, and $1 */
char **global_argv;
int global_argc;
int last_return_code;
const char *ifs;
struct close_me *close_me_head;
const char *cwd;
unsigned last_bg_pid;
struct variables *top_vars; /* = &shell_ver (both are set in main()) */
struct variables shell_ver; /* = const_shell_ver */
#if ENABLE_FEATURE_SH_STANDALONE
struct nofork_save_area nofork_save;
#endif
#if ENABLE_HUSH_JOB
sigjmp_buf toplevel_jb;
#endif
unsigned char charmap[256];
char user_input_buf[ENABLE_FEATURE_EDITING ? BUFSIZ : 2];
};
#define G (*ptr_to_globals)
#if !ENABLE_HUSH_INTERACTIVE
enum { interactive_fd = 0 };
#endif
#if !ENABLE_HUSH_JOB
enum { run_list_level = 0 };
#endif
#if ENABLE_HUSH_INTERACTIVE
#define interactive_fd (G.interactive_fd )
#define PS1 (G.PS1 )
#define PS2 (G.PS2 )
#endif
#if ENABLE_FEATURE_EDITING
#define line_input_state (G.line_input_state)
#endif
#if ENABLE_HUSH_JOB
#define run_list_level (G.run_list_level )
#define saved_task_pgrp (G.saved_task_pgrp )
#define saved_tty_pgrp (G.saved_tty_pgrp )
#define last_jobid (G.last_jobid )
#define job_list (G.job_list )
#define toplevel_list (G.toplevel_list )
#define toplevel_jb (G.toplevel_jb )
#define ctrl_z_flag (G.ctrl_z_flag )
#endif /* JOB */
#define global_argv (G.global_argv )
#define global_argc (G.global_argc )
#define last_return_code (G.last_return_code)
#define ifs (G.ifs )
#define fake_mode (G.fake_mode )
#define close_me_head (G.close_me_head )
#define cwd (G.cwd )
#define last_bg_pid (G.last_bg_pid )
#define top_vars (G.top_vars )
#define shell_ver (G.shell_ver )
#if ENABLE_FEATURE_SH_STANDALONE
#define nofork_save (G.nofork_save )
#endif
#if ENABLE_HUSH_JOB
#define toplevel_jb (G.toplevel_jb )
#endif
#define charmap (G.charmap )
#define user_input_buf (G.user_input_buf )
#define B_CHUNK 100
#define B_NOSPAC 1
#define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n"
static void __syntax(int line)
{
bb_error_msg("syntax error hush.c:%d", line);
@ -457,6 +514,12 @@ static void unset_local_var(const char *name);
* 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 */
const char *descr; /* description */
int (*function) (char **argv); /* function ptr */
};
static const struct built_in_command bltins[] = {
#if ENABLE_HUSH_JOB
{ "bg", "Resume a job in the background", builtin_fg_bg },
@ -487,10 +550,6 @@ static const struct built_in_command bltins[] = {
{ NULL, NULL, NULL }
};
#if ENABLE_FEATURE_SH_STANDALONE
struct nofork_save_area nofork_save;
#endif
#if ENABLE_HUSH_JOB
/* move to libbb? */
@ -539,9 +598,6 @@ static void set_every_sighandler(void (*handler)(int))
signal(SIGCHLD, handler);
}
static struct pipe *toplevel_list;
static sigjmp_buf toplevel_jb;
smallint ctrl_z_flag;
static void handler_ctrl_c(int sig)
{
debug_printf_jobs("got sig %d\n", sig);
@ -1062,14 +1118,8 @@ static const char* setup_prompt_string(int promptmode)
return prompt_str;
}
#if ENABLE_FEATURE_EDITING
static line_input_t *line_input_state;
#endif
static void get_user_input(struct in_str *i)
{
static char the_command[ENABLE_FEATURE_EDITING ? BUFSIZ : 2];
int r;
const char *prompt_str;
@ -1081,20 +1131,20 @@ static void get_user_input(struct in_str *i)
** atexit() handlers and other unwanted stuff to our
** child processes (rob@sysgo.de)
*/
r = read_line_input(prompt_str, the_command, BUFSIZ-1, line_input_state);
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 */
the_command[0] = EOF; /* yes, it will be truncated, it's ok */
the_command[1] = '\0';
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);
the_command[0] = r = fgetc(i->file);
/*the_command[1] = '\0'; - already is and never changed */
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 = the_command;
i->p = user_input_buf;
}
#endif /* INTERACTIVE */
@ -1879,12 +1929,6 @@ static void debug_print_tree(struct pipe *pi, int lvl)
* global data until exec/_exit (we can be a child after vfork!) */
static int run_list_real(struct pipe *pi)
{
#if ENABLE_HUSH_JOB
static int level;
#else
enum { level = 0 };
#endif
char *for_varname = NULL;
char **for_lcur = NULL;
char **for_list = NULL;
@ -1897,7 +1941,7 @@ static int run_list_real(struct pipe *pi)
int if_code = 0, next_if_code = 0; /* need double-buffer to handle elif */
reserved_style rmode, skip_more_in_this_rmode = RES_XXXX;
debug_printf_exec("run_list_real start lvl %d\n", level + 1);
debug_printf_exec("run_list_real start lvl %d\n", run_list_level + 1);
/* check syntax for "for" */
for (rpipe = pi; rpipe; rpipe = rpipe->next) {
@ -1905,7 +1949,7 @@ static int run_list_real(struct pipe *pi)
&& (rpipe->next == NULL)
) {
syntax(); /* unterminated FOR (no IN or no commands after IN) */
debug_printf_exec("run_list_real lvl %d return 1\n", level);
debug_printf_exec("run_list_real lvl %d return 1\n", run_list_level);
return 1;
}
if ((rpipe->r_mode == RES_IN && rpipe->next->r_mode == RES_IN && rpipe->next->progs[0].argv != NULL)
@ -1913,7 +1957,7 @@ static int run_list_real(struct pipe *pi)
) {
/* TODO: what is tested in the first condition? */
syntax(); /* 2nd: malformed FOR (not followed by IN) */
debug_printf_exec("run_list_real lvl %d return 1\n", level);
debug_printf_exec("run_list_real lvl %d return 1\n", run_list_level);
return 1;
}
}
@ -1923,7 +1967,7 @@ static int run_list_real(struct pipe *pi)
* 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 (++level == 1 && interactive_fd) {
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 */
@ -1931,7 +1975,7 @@ static int run_list_real(struct pipe *pi)
signal(SIGTSTP, SIG_IGN);
/* Restore level (we can be coming from deep inside
* nested levels) */
level = 1;
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");
@ -2039,7 +2083,7 @@ static int run_list_real(struct pipe *pi)
/* Even bash 3.2 doesn't do that well with nested bg:
* try "{ { sleep 10; echo DEEP; } & echo HERE; } &".
* I'm considering NOT treating inner bgs as jobs -
* thus maybe "if (level == 1 && pi->followup == PIPE_BG)"
* thus maybe "if (run_list_level == 1 && pi->followup == PIPE_BG)"
* above? */
#if ENABLE_HUSH_JOB
insert_bg_job(pi);
@ -2048,7 +2092,7 @@ static int run_list_real(struct pipe *pi)
} else {
#if ENABLE_HUSH_JOB
/* Paranoia, just "interactive_fd" should be enough */
if (level == 1 && interactive_fd) {
if (run_list_level == 1 && interactive_fd) {
rcode = checkjobs_and_fg_shell(pi);
} else
#endif
@ -2081,9 +2125,9 @@ static int run_list_real(struct pipe *pi)
exit(rcode);
}
ret:
level--;
run_list_level--;
#endif
debug_printf_exec("run_list_real lvl %d return %d\n", level + 1, rcode);
debug_printf_exec("run_list_real lvl %d return %d\n", run_list_level + 1, rcode);
return rcode;
}
@ -3544,40 +3588,25 @@ int hush_main(int argc, char **argv)
FILE *input;
char **e;
PTR_TO_GLOBALS = xzalloc(sizeof(G));
top_vars = &shell_ver;
shell_ver = const_shell_ver; /* copying struct here */
#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;
/* (re?) initialize globals. Sometimes hush_main() ends up calling
* hush_main(), therefore we cannot rely on the BSS to zero out this
* stuff. Reset these to 0 every time. */
ifs = NULL;
/* charmap[] is taken care of with call to update_charmap() */
fake_mode = 0;
close_me_head = NULL;
#if ENABLE_HUSH_INTERACTIVE
interactive_fd = 0;
#endif
#if ENABLE_HUSH_JOB
last_bg_pid = 0;
job_list = NULL;
last_jobid = 0;
#endif
/* Initialize some more globals to non-zero values */
set_cwd();
#if ENABLE_HUSH_INTERACTIVE
#if ENABLE_FEATURE_EDITING
cmdedit_set_initial_prompt();
#else
PS1 = NULL;
#endif
PS2 = "> ";
#endif
/* initialize our shell local variables with the values
* currently living in the environment */
e = environ;
@ -3612,7 +3641,7 @@ int hush_main(int argc, char **argv)
/* interactive_fd++; */
break;
case 'f':
fake_mode++;
fake_mode = 1;
break;
default:
#ifndef BB_VER