busybox/msh.c
Eric Andersen ff9eee475f This is a busybox port of the Minix shell. It is reasonably capable,
handles all the basic stuff (for, case/esac, while, if/then/else), and
is very small (adds just 38k on x86).  It is not as rigorously correct
about Bourne semantics as bash, but for most things it is quite
workable.  There is still some work to be done to further shrink it (it
has its own globbing functions instead of using the libc ones, for
example), but it is quite usable as is.
 -Erik
2001-06-29 04:57:14 +00:00

4800 lines
84 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Minix shell port for busybox
*
* This version of the Minix shell was adapted for use in busybox
* by Erik Andersen <andersee@debian.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Original copyright notice is retained at the end of this file.
*/
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <setjmp.h>
#include <signal.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/times.h>
#include <sys/types.h>
#include <sys/wait.h>
#include "cmdedit.h"
#include "busybox.h"
/* -------- sh.h -------- */
/*
* shell
*/
#define LINELIM 2100
#define NPUSH 8 /* limit to input nesting */
#define NOFILE 20 /* Number of open files */
#define NUFILE 10 /* Number of user-accessible files */
#define FDBASE 10 /* First file usable by Shell */
/*
* values returned by wait
*/
#define WAITSIG(s) ((s)&0177)
#define WAITVAL(s) (((s)>>8)&0377)
#define WAITCORE(s) (((s)&0200)!=0)
/*
* library and system defintions
*/
typedef void xint; /* base type of jmp_buf, for not broken compilers */
/*
* shell components
*/
#define QUOTE 0200
#define NOBLOCK ((struct op *)NULL)
#define NOWORD ((char *)NULL)
#define NOWORDS ((char **)NULL)
#define NOPIPE ((int *)NULL)
/*
* Description of a command or an operation on commands.
* Might eventually use a union.
*/
struct op {
int type; /* operation type, see below */
char **words; /* arguments to a command */
struct ioword **ioact; /* IO actions (eg, < > >>) */
struct op *left;
struct op *right;
char *str; /* identifier for case and for */
};
#define TCOM 1 /* command */
#define TPAREN 2 /* (c-list) */
#define TPIPE 3 /* a | b */
#define TLIST 4 /* a [&;] b */
#define TOR 5 /* || */
#define TAND 6 /* && */
#define TFOR 7
#define TDO 8
#define TCASE 9
#define TIF 10
#define TWHILE 11
#define TUNTIL 12
#define TELIF 13
#define TPAT 14 /* pattern in case */
#define TBRACE 15 /* {c-list} */
#define TASYNC 16 /* c & */
/*
* actions determining the environment of a process
*/
#define BIT(i) (1<<(i))
#define FEXEC BIT(0) /* execute without forking */
/*
* flags to control evaluation of words
*/
#define DOSUB 1 /* interpret $, `, and quotes */
#define DOBLANK 2 /* perform blank interpretation */
#define DOGLOB 4 /* interpret [?* */
#define DOKEY 8 /* move words with `=' to 2nd arg. list */
#define DOTRIM 16 /* trim resulting string */
#define DOALL (DOSUB|DOBLANK|DOGLOB|DOKEY|DOTRIM)
static char **dolv;
static int dolc;
static int exstat;
static char gflg;
static int interactive; /* Is this an interactive shell */
static int execflg;
static int multiline; /* \n changed to ; */
static struct op *outtree; /* result from parser */
static xint *failpt;
static xint *errpt;
static struct brkcon *brklist;
static int isbreak;
static int newfile(char *s);
static char *findeq(char *cp);
static char *cclass(char *p, int sub);
static void initarea(void);
extern int shell_main(int argc, char **argv);
struct brkcon {
jmp_buf brkpt;
struct brkcon *nextlev;
} ;
/*
* redirection
*/
struct ioword {
short io_unit; /* unit affected */
short io_flag; /* action (below) */
char *io_name; /* file name */
};
#define IOREAD 1 /* < */
#define IOHERE 2 /* << (here file) */
#define IOWRITE 4 /* > */
#define IOCAT 8 /* >> */
#define IOXHERE 16 /* ${}, ` in << */
#define IODUP 32 /* >&digit */
#define IOCLOSE 64 /* >&- */
#define IODEFAULT (-1) /* token for default IO unit */
static struct wdblock *wdlist;
static struct wdblock *iolist;
/*
* parsing & execution environment
*/
static struct env {
char *linep;
struct io *iobase;
struct io *iop;
xint *errpt;
int iofd;
struct env *oenv;
} e;
/*
* flags:
* -e: quit on error
* -k: look for name=value everywhere on command line
* -n: no execution
* -t: exit after reading and executing one command
* -v: echo as read
* -x: trace
* -u: unset variables net diagnostic
*/
static char *flag;
static char *null; /* null value for variable */
static int intr; /* interrupt pending */
static char *trap[_NSIG+1];
static char ourtrap[_NSIG+1];
static int trapset; /* trap pending */
static int heedint; /* heed interrupt signals */
static int yynerrs; /* yacc */
static char line[LINELIM];
static char *elinep;
/*
* other functions
*/
static int (*inbuilt(char *s ))(void);
static char *rexecve (char *c , char **v, char **envp );
static char *space (int n );
static char *strsave (char *s, int a );
static char *evalstr (char *cp, int f );
static char *putn (int n );
static char *itoa (unsigned u, int n );
static char *unquote (char *as );
static struct var *lookup (char *n );
static int rlookup (char *n );
static struct wdblock *glob (char *cp, struct wdblock *wb );
static int my_getc( int ec);
static int subgetc (int ec, int quoted );
static char **makenv (void);
static char **eval (char **ap, int f );
static int setstatus (int s );
static int waitfor (int lastpid, int canintr );
static void onintr (int s ); /* SIGINT handler */
static int newenv (int f );
static void quitenv (void);
static void err (char *s );
static int anys (char *s1, char *s2 );
static int any (int c, char *s );
static void next (int f );
static void setdash (void);
static void onecommand (void);
static void runtrap (int i );
static int gmatch (char *s, char *p );
/*
* error handling
*/
static void leave (void); /* abort shell (or fail in subshell) */
static void fail (void); /* fail but return to process next command */
static void warn (char *s );
static void sig (int i ); /* default signal handler */
/* -------- area stuff -------- */
#define REGSIZE sizeof(struct region)
#define GROWBY 256
//#define SHRINKBY 64
#undef SHRINKBY
#define FREE 32767
#define BUSY 0
#define ALIGN (sizeof(int)-1)
struct region {
struct region *next;
int area;
};
/* -------- grammar stuff -------- */
typedef union {
char *cp;
char **wp;
int i;
struct op *o;
} YYSTYPE;
#define WORD 256
#define LOGAND 257
#define LOGOR 258
#define BREAK 259
#define IF 260
#define THEN 261
#define ELSE 262
#define ELIF 263
#define FI 264
#define CASE 265
#define ESAC 266
#define FOR 267
#define WHILE 268
#define UNTIL 269
#define DO 270
#define DONE 271
#define IN 272
#define YYERRCODE 300
/* flags to yylex */
#define CONTIN 01 /* skip new lines to complete command */
#define SYNTAXERR zzerr()
static struct op *pipeline(int cf );
static struct op *andor(void);
static struct op *c_list(void);
static int synio(int cf );
static void musthave (int c, int cf );
static struct op *simple(void);
static struct op *nested(int type, int mark );
static struct op *command(int cf );
static struct op *dogroup(int onlydone );
static struct op *thenpart(void);
static struct op *elsepart(void);
static struct op *caselist(void);
static struct op *casepart(void);
static char **pattern(void);
static char **wordlist(void);
static struct op *list(struct op *t1, struct op *t2 );
static struct op *block(int type, struct op *t1, struct op *t2, char **wp );
static struct op *newtp(void);
static struct op *namelist(struct op *t );
static char **copyw(void);
static void word(char *cp );
static struct ioword **copyio(void);
static struct ioword *io (int u, int f, char *cp );
static void zzerr(void);
static void yyerror(char *s );
static int yylex(int cf );
static int collect(int c, int c1 );
static int dual(int c );
static void diag(int ec );
static char *tree(unsigned size );
/* -------- var.h -------- */
struct var {
char *value;
char *name;
struct var *next;
char status;
};
#define COPYV 1 /* flag to setval, suggesting copy */
#define RONLY 01 /* variable is read-only */
#define EXPORT 02 /* variable is to be exported */
#define GETCELL 04 /* name & value space was got with getcell */
static struct var *vlist; /* dictionary */
static struct var *homedir; /* home directory */
static struct var *prompt; /* main prompt */
static struct var *cprompt; /* continuation prompt */
static struct var *path; /* search path for commands */
static struct var *shell; /* shell to interpret command files */
static struct var *ifs; /* field separators */
static int yyparse (void);
static struct var *lookup (char *n );
static void setval (struct var *vp, char *val );
static void nameval (struct var *vp, char *val, char *name );
static void export (struct var *vp );
static void ronly (struct var *vp );
static int isassign (char *s );
static int checkname (char *cp );
static int assign (char *s, int cf );
static void putvlist (int f, int out );
static int eqname (char *n1, char *n2 );
static int execute (struct op *t, int *pin, int *pout, int act );
/* -------- io.h -------- */
/* io buffer */
struct iobuf {
unsigned id; /* buffer id */
char buf[512]; /* buffer */
char *bufp; /* pointer into buffer */
char *ebufp; /* pointer to end of buffer */
};
/* possible arguments to an IO function */
struct ioarg {
char *aword;
char **awordlist;
int afile; /* file descriptor */
unsigned afid; /* buffer id */
long afpos; /* file position */
struct iobuf *afbuf; /* buffer for this file */
};
//static struct ioarg ioargstack[NPUSH];
#define AFID_NOBUF (~0)
#define AFID_ID 0
/* an input generator's state */
struct io {
int (*iofn)();
struct ioarg *argp;
int peekc;
char prev; /* previous character read by readc() */
char nlcount; /* for `'s */
char xchar; /* for `'s */
char task; /* reason for pushed IO */
};
//static struct io iostack[NPUSH];
#define XOTHER 0 /* none of the below */
#define XDOLL 1 /* expanding ${} */
#define XGRAVE 2 /* expanding `'s */
#define XIO 3 /* file IO */
/* in substitution */
#define INSUB() (e.iop->task == XGRAVE || e.iop->task == XDOLL)
/*
* input generators for IO structure
*/
static int nlchar (struct ioarg *ap );
static int strchar (struct ioarg *ap );
static int qstrchar (struct ioarg *ap );
static int filechar (struct ioarg *ap );
static int herechar (struct ioarg *ap );
static int linechar (struct ioarg *ap );
static int gravechar (struct ioarg *ap, struct io *iop );
static int qgravechar (struct ioarg *ap, struct io *iop );
static int dolchar (struct ioarg *ap );
static int wdchar (struct ioarg *ap );
static void scraphere (void);
static void freehere (int area );
static void gethere (void);
static void markhere (char *s, struct ioword *iop );
static int herein (char *hname, int xdoll );
static int run (struct ioarg *argp, int (*f)());
/*
* IO functions
*/
static int eofc (void);
static int readc (void);
static void unget (int c );
static void ioecho (int c );
static void prs (char *s );
static void prn (unsigned u );
static void closef (int i );
static void closeall (void);
/*
* IO control
*/
static void pushio (struct ioarg *argp, int (*fn)());
static int remap (int fd );
static int openpipe (int *pv );
static void closepipe (int *pv );
static struct io *setbase (struct io *ip );
static struct ioarg temparg; /* temporary for PUSHIO */
#define PUSHIO(what,arg,gen) ((temparg.what = (arg)),pushio(&temparg,(gen)))
#define RUN(what,arg,gen) ((temparg.what = (arg)), run(&temparg,(gen)))
/* -------- word.h -------- */
#define NSTART 16 /* default number of words to allow for initially */
struct wdblock {
short w_bsize;
short w_nword;
/* bounds are arbitrary */
char *w_words[1];
};
static struct wdblock *addword (char *wd, struct wdblock *wb );
static struct wdblock *newword (int nw );
static char **getwords (struct wdblock *wb );
/* -------- area.h -------- */
/*
* storage allocation
*/
static char *getcell (unsigned nbytes );
static void garbage (void);
static void setarea (char *cp, int a );
static int getarea (char *cp );
static void freearea (int a );
static void freecell (char *cp );
static int areanum; /* current allocation area */
#define NEW(type) (type *)getcell(sizeof(type))
#define DELETE(obj) freecell((char *)obj)
/* -------- misc stuff -------- */
static int forkexec (struct op *t, int *pin, int *pout, int act, char **wp, int *pforked );
static int iosetup (struct ioword *iop, int pipein, int pipeout );
static void echo(char **wp );
static struct op **find1case (struct op *t, char *w );
static struct op *findcase (struct op *t, char *w );
static void brkset(struct brkcon *bc );
static int dolabel(void);
static int dochdir(struct op *t );
static int doshift(struct op *t );
static int dologin(struct op *t );
static int doumask(struct op *t );
static int doexec(struct op *t );
static int dodot(struct op *t );
static int dowait(struct op *t );
static int doread(struct op *t );
static int doeval(struct op *t );
static int dotrap(struct op *t );
static int getsig(char *s );
static void setsig (int n, void (*f)());
static int getn(char *as );
static int dobreak(struct op *t );
static int docontinue(struct op *t );
static int brkcontin (char *cp, int val );
static int doexit(struct op *t );
static int doexport(struct op *t );
static int doreadonly(struct op *t );
static void rdexp (char **wp, void (*f)(), int key);
static void badid(char *s );
static int doset(struct op *t );
static void varput (char *s, int out );
static int dotimes(void);
static int expand (char *cp, struct wdblock **wbp, int f );
static char *blank(int f );
static int dollar(int quoted );
static int grave(int quoted );
static void globname (char *we, char *pp );
static char *generate (char *start1, char *end1, char *middle, char *end );
static int anyspcl(struct wdblock *wb );
static int xstrcmp (char *p1, char *p2 );
static void glob0 (char *a0, unsigned int a1, int a2, int (*a3)(char *, char *));
static void glob1 (char *base, char *lim );
static void glob2 (char *i, char *j );
static void glob3 (char *i, char *j, char *k );
static void readhere (char **name, char *s, int ec );
static void pushio(struct ioarg *argp, int (*fn)());
static int xxchar(struct ioarg *ap );
struct here {
char *h_tag;
int h_dosub;
struct ioword *h_iop;
struct here *h_next;
};
static char *signame[] = {
"Signal 0",
"Hangup",
(char *)NULL, /* interrupt */
"Quit",
"Illegal instruction",
"Trace/BPT trap",
"Abort",
"Bus error",
"Floating Point Exception",
"Killed",
"SIGUSR1",
"SIGSEGV",
"SIGUSR2",
(char *)NULL, /* broken pipe */
"Alarm clock",
"Terminated",
};
#define NSIGNAL (sizeof(signame)/sizeof(signame[0]))
struct res {
char *r_name;
int r_val;
};
static struct res restab[] = {
{"for", FOR},
{"case", CASE},
{"esac", ESAC},
{"while", WHILE},
{"do", DO},
{"done", DONE},
{"if", IF},
{"in", IN},
{"then", THEN},
{"else", ELSE},
{"elif", ELIF},
{"until", UNTIL},
{"fi", FI},
{";;", BREAK},
{"||", LOGOR},
{"&&", LOGAND},
{"{", '{'},
{"}", '}'},
{0, 0},
};
struct builtin {
char *command;
int (*fn)();
};
static struct builtin builtin[] = {
{":", dolabel},
{"cd", dochdir},
{"shift", doshift},
{"exec", doexec},
{"wait", dowait},
{"read", doread},
{"eval", doeval},
{"trap", dotrap},
{"break", dobreak},
{"continue",docontinue},
{"exit", doexit},
{"export", doexport},
{"readonly",doreadonly},
{"set", doset},
{".", dodot},
{"umask", doumask},
{"login", dologin},
{"newgrp", dologin},
{"times", dotimes},
{0,0}
};
/* Globals */
extern char **environ; /* environment pointer */
static char **dolv;
static int dolc;
static int exstat;
static char gflg;
static int interactive; /* Is this an interactive shell */
static int execflg;
static int multiline; /* \n changed to ; */
static struct op *outtree; /* result from parser */
static xint *failpt;
static xint *errpt;
static struct brkcon *brklist;
static int isbreak;
static struct wdblock *wdlist;
static struct wdblock *iolist;
static char *trap[_NSIG+1];
static char ourtrap[_NSIG+1];
static int trapset; /* trap pending */
static int yynerrs; /* yacc */
static char line[LINELIM];
static struct var *vlist; /* dictionary */
static struct var *homedir; /* home directory */
static struct var *prompt; /* main prompt */
static struct var *cprompt; /* continuation prompt */
static struct var *path; /* search path for commands */
static struct var *shell; /* shell to interpret command files */
static struct var *ifs; /* field separators */
static struct ioarg ioargstack[NPUSH];
static struct io iostack[NPUSH];
static int areanum; /* current allocation area */
static int intr;
static int inparse;
static char flags['z'-'a'+1];
static char *flag = flags-'a';
static char *elinep = line+sizeof(line)-5;
static char *null = "";
static int heedint =1;
static struct env e ={line, iostack, iostack-1, (xint *)NULL, FDBASE, (struct env *)NULL};
static void (*qflag)(int) = SIG_IGN;
static char shellname[] = "/bin/sh";
static char search[] = ":/bin:/usr/bin";
static int startl;
static int peeksym;
static int nlseen;
static int iounit = IODEFAULT;
static YYSTYPE yylval;
static struct iobuf sharedbuf = {AFID_NOBUF};
static struct iobuf mainbuf = {AFID_NOBUF};
static unsigned bufid = AFID_ID; /* buffer id counter */
static struct ioarg temparg = {0, 0, 0, AFID_NOBUF, 0};
static struct here *inhere; /* list of hear docs while parsing */
static struct here *acthere; /* list of active here documents */
static struct region *areabot; /* bottom of area */
static struct region *areatop; /* top of area */
static struct region *areanxt; /* starting point of scan */
static void * brktop;
static void * brkaddr;
#ifdef BB_FEATURE_COMMAND_EDITING
char * current_prompt;
unsigned int shell_context;
#endif
/* -------- sh.c -------- */
/*
* shell
*/
extern int shell_main(int argc, char **argv)
{
register int f;
register char *s;
int cflag;
char *name, **ap;
int (*iof)();
initarea();
if ((ap = environ) != NULL) {
while (*ap)
assign(*ap++, !COPYV);
for (ap = environ; *ap;)
export(lookup(*ap++));
}
closeall();
areanum = 1;
shell = lookup("SHELL");
if (shell->value == null)
setval(shell, shellname);
export(shell);
homedir = lookup("HOME");
if (homedir->value == null)
setval(homedir, "/");
export(homedir);
setval(lookup("$"), itoa(getpid(), 5));
path = lookup("PATH");
if (path->value == null)
setval(path, search);
export(path);
ifs = lookup("IFS");
if (ifs->value == null)
setval(ifs, " \t\n");
prompt = lookup("PS1");
if (prompt->value == null)
setval(prompt, "$ ");
if (geteuid() == 0) {
setval(prompt, "# ");
prompt->status &= ~EXPORT;
}
cprompt = lookup("PS2");
if (cprompt->value == null)
setval(cprompt, "> ");
iof = filechar;
cflag = 0;
name = *argv++;
if (--argc >= 1) {
if(argv[0][0] == '-' && argv[0][1] != '\0') {
for (s = argv[0]+1; *s; s++)
switch (*s) {
case 'c':
prompt->status &= ~EXPORT;
cprompt->status &= ~EXPORT;
setval(prompt, "");
setval(cprompt, "");
cflag = 1;
if (--argc > 0)
PUSHIO(aword, *++argv, iof = nlchar);
break;
case 'q':
qflag = SIG_DFL;
break;
case 's':
/* standard input */
break;
case 't':
prompt->status &= ~EXPORT;
setval(prompt, "");
iof = linechar;
break;
case 'i':
interactive++;
default:
if (*s>='a' && *s<='z')
flag[(int)*s]++;
}
} else {
argv--;
argc++;
}
if (iof == filechar && --argc > 0) {
setval(prompt, "");
setval(cprompt, "");
prompt->status &= ~EXPORT;
cprompt->status &= ~EXPORT;
if (newfile(name = *++argv))
exit(1);
}
}
setdash();
if (e.iop < iostack) {
PUSHIO(afile, 0, iof);
if (isatty(0) && isatty(1) && !cflag)
interactive++;
}
signal(SIGQUIT, qflag);
if (name && name[0] == '-') {
interactive++;
if ((f = open(".profile", 0)) >= 0)
next(remap(f));
if ((f = open("/etc/profile", 0)) >= 0)
next(remap(f));
}
if (interactive)
signal(SIGTERM, sig);
if (signal(SIGINT, SIG_IGN) != SIG_IGN)
signal(SIGINT, onintr);
dolv = argv;
dolc = argc;
dolv[0] = name;
if (dolc > 1) {
for (ap = ++argv; --argc > 0;) {
if (assign(*ap = *argv++, !COPYV)) {
dolc--; /* keyword */
} else {
ap++;
}
}
}
setval(lookup("#"), putn((--dolc < 0) ? (dolc = 0) : dolc));
for (;;) {
if (interactive && e.iop <= iostack) {
#ifdef BB_FEATURE_COMMAND_EDITING
current_prompt=prompt->value;
#else
prs(prompt->value);
#endif
}
onecommand();
}
}
static void
setdash()
{
register char *cp;
register int c;
char m['z'-'a'+1];
cp = m;
for (c='a'; c<='z'; c++)
if (flag[c])
*cp++ = c;
*cp = 0;
setval(lookup("-"), m);
}
static int
newfile(s)
register char *s;
{
register int f;
if (strcmp(s, "-") != 0) {
f = open(s, 0);
if (f < 0) {
prs(s);
err(": cannot open");
return(1);
}
} else
f = 0;
next(remap(f));
return(0);
}
static void
onecommand()
{
register int i;
jmp_buf m1;
while (e.oenv)
quitenv();
areanum = 1;
freehere(areanum);
freearea(areanum);
garbage();
wdlist = 0;
iolist = 0;
e.errpt = 0;
e.linep = line;
yynerrs = 0;
multiline = 0;
inparse = 1;
intr = 0;
execflg = 0;
setjmp(failpt = m1); /* Bruce Evans' fix */
if (setjmp(failpt = m1) || yyparse() || intr) {
while (e.oenv)
quitenv();
scraphere();
if (!interactive && intr)
leave();
inparse = 0;
intr = 0;
return;
}
inparse = 0;
brklist = 0;
intr = 0;
execflg = 0;
if (!flag['n'])
execute(outtree, NOPIPE, NOPIPE, 0);
if (!interactive && intr) {
execflg = 0;
leave();
}
if ((i = trapset) != 0) {
trapset = 0;
runtrap(i);
}
}
static void
fail()
{
longjmp(failpt, 1);
/* NOTREACHED */
}
static void
leave()
{
if (execflg)
fail();
scraphere();
freehere(1);
runtrap(0);
exit(exstat);
/* NOTREACHED */
}
static void
warn(s)
register char *s;
{
if(*s) {
prs(s);
exstat = -1;
}
prs("\n");
if (flag['e'])
leave();
}
static void
err(s)
char *s;
{
warn(s);
if (flag['n'])
return;
if (!interactive)
leave();
if (e.errpt)
longjmp(e.errpt, 1);
closeall();
e.iop = e.iobase = iostack;
}
static int
newenv(f)
int f;
{
register struct env *ep;
if (f) {
quitenv();
return(1);
}
ep = (struct env *) space(sizeof(*ep));
if (ep == NULL) {
while (e.oenv)
quitenv();
fail();
}
*ep = e;
e.oenv = ep;
e.errpt = errpt;
return(0);
}
static void
quitenv()
{
register struct env *ep;
register int fd;
if ((ep = e.oenv) != NULL) {
fd = e.iofd;
e = *ep;
/* should close `'d files */
DELETE(ep);
while (--fd >= e.iofd)
close(fd);
}
}
/*
* Is any character from s1 in s2?
*/
static int
anys(s1, s2)
register char *s1, *s2;
{
while (*s1)
if (any(*s1++, s2))
return(1);
return(0);
}
/*
* Is character c in s?
*/
static int
any(c, s)
register int c;
register char *s;
{
while (*s)
if (*s++ == c)
return(1);
return(0);
}
static char *
putn(n)
register int n;
{
return(itoa(n, -1));
}
static char *
itoa(u, n)
register unsigned u;
int n;
{
register char *cp;
static char s[20];
int m;
m = 0;
if (n < 0 && (int) u < 0) {
m++;
u = -u;
}
cp = s+sizeof(s);
*--cp = 0;
do {
*--cp = u%10 + '0';
u /= 10;
} while (--n > 0 || u);
if (m)
*--cp = '-';
return(cp);
}
static void
next(f)
int f;
{
PUSHIO(afile, f, filechar);
}
static void
onintr(s)
int s; /* ANSI C requires a parameter */
{
signal(SIGINT, onintr);
intr = 1;
if (interactive) {
if (inparse) {
prs("\n");
fail();
}
}
else if (heedint) {
execflg = 0;
leave();
}
}
static char *
space(n)
int n;
{
register char *cp;
if ((cp = getcell(n)) == 0)
err("out of string space");
return(cp);
}
static char *
strsave(s, a)
register char *s;
int a;
{
register char *cp, *xp;
if ((cp = space(strlen(s)+1)) != NULL) {
setarea((char *)cp, a);
for (xp = cp; (*xp++ = *s++) != '\0';)
;
return(cp);
}
return("");
}
/*
* trap handling
*/
static void
sig(i)
register int i;
{
trapset = i;
signal(i, sig);
}
static void runtrap(i)
int i;
{
char *trapstr;
if ((trapstr = trap[i]) == NULL)
return;
if (i == 0)
trap[i] = 0;
RUN(aword, trapstr, nlchar);
}
/* -------- var.c -------- */
/*
* Find the given name in the dictionary
* and return its value. If the name was
* not previously there, enter it now and
* return a null value.
*/
static struct var *
lookup(n)
register char *n;
{
register struct var *vp;
register char *cp;
register int c;
static struct var dummy;
if (isdigit(*n)) {
dummy.name = n;
for (c = 0; isdigit(*n) && c < 1000; n++)
c = c*10 + *n-'0';
dummy.status = RONLY;
dummy.value = c <= dolc? dolv[c]: null;
return(&dummy);
}
for (vp = vlist; vp; vp = vp->next)
if (eqname(vp->name, n))
return(vp);
cp = findeq(n);
vp = (struct var *)space(sizeof(*vp));
if (vp == 0 || (vp->name = space((int)(cp-n)+2)) == 0) {
dummy.name = dummy.value = "";
return(&dummy);
}
for (cp = vp->name; (*cp = *n++) && *cp != '='; cp++)
;
if (*cp == 0)
*cp = '=';
*++cp = 0;
setarea((char *)vp, 0);
setarea((char *)vp->name, 0);
vp->value = null;
vp->next = vlist;
vp->status = GETCELL;
vlist = vp;
return(vp);
}
/*
* give variable at `vp' the value `val'.
*/
static void
setval(vp, val)
struct var *vp;
char *val;
{
nameval(vp, val, (char *)NULL);
}
/*
* if name is not NULL, it must be
* a prefix of the space `val',
* and end with `='.
* this is all so that exporting
* values is reasonably painless.
*/
static void
nameval(vp, val, name)
register struct var *vp;
char *val, *name;
{
register char *cp, *xp;
char *nv;
int fl;
if (vp->status & RONLY) {
for (xp = vp->name; *xp && *xp != '=';)
putc(*xp++, stderr);
err(" is read-only");
return;
}
fl = 0;
if (name == NULL) {
xp = space(strlen(vp->name)+strlen(val)+2);
if (xp == 0)
return;
/* make string: name=value */
setarea((char *)xp, 0);
name = xp;
for (cp = vp->name; (*xp = *cp++) && *xp!='='; xp++)
;
if (*xp++ == 0)
xp[-1] = '=';
nv = xp;
for (cp = val; (*xp++ = *cp++) != '\0';)
;
val = nv;
fl = GETCELL;
}
if (vp->status & GETCELL)
freecell(vp->name); /* form new string `name=value' */
vp->name = name;
vp->value = val;
vp->status |= fl;
}
static void
export(vp)
struct var *vp;
{
vp->status |= EXPORT;
}
static void
ronly(vp)
struct var *vp;
{
if (isalpha(vp->name[0])) /* not an internal symbol ($# etc) */
vp->status |= RONLY;
}
static int
isassign(s)
register char *s;
{
if (!isalpha((int)*s))
return(0);
for (; *s != '='; s++)
if (*s == 0 || !isalnum(*s))
return(0);
return(1);
}
static int
assign(s, cf)
register char *s;
int cf;
{
register char *cp;
struct var *vp;
if (!isalpha(*s))
return(0);
for (cp = s; *cp != '='; cp++)
if (*cp == 0 || !isalnum(*cp))
return(0);
vp = lookup(s);
nameval(vp, ++cp, cf == COPYV? (char *)NULL: s);
if (cf != COPYV)
vp->status &= ~GETCELL;
return(1);
}
static int
checkname(cp)
register char *cp;
{
if (!isalpha(*cp++))
return(0);
while (*cp)
if (!isalnum(*cp++))
return(0);
return(1);
}
static void
putvlist(f, out)
register int f, out;
{
register struct var *vp;
for (vp = vlist; vp; vp = vp->next)
if (vp->status & f && isalpha(*vp->name)) {
if (vp->status & EXPORT)
write(out, "export ", 7);
if (vp->status & RONLY)
write(out, "readonly ", 9);
write(out, vp->name, (int)(findeq(vp->name) - vp->name));
write(out, "\n", 1);
}
}
static int
eqname(n1, n2)
register char *n1, *n2;
{
for (; *n1 != '=' && *n1 != 0; n1++)
if (*n2++ != *n1)
return(0);
return(*n2 == 0 || *n2 == '=');
}
static char *
findeq(cp)
register char *cp;
{
while (*cp != '\0' && *cp != '=')
cp++;
return(cp);
}
/* -------- gmatch.c -------- */
/*
* int gmatch(string, pattern)
* char *string, *pattern;
*
* Match a pattern as in sh(1).
*/
#define CMASK 0377
#define QUOTE 0200
#define QMASK (CMASK&~QUOTE)
#define NOT '!' /* might use ^ */
static int
gmatch(s, p)
register char *s, *p;
{
register int sc, pc;
if (s == NULL || p == NULL)
return(0);
while ((pc = *p++ & CMASK) != '\0') {
sc = *s++ & QMASK;
switch (pc) {
case '[':
if ((p = cclass(p, sc)) == NULL)
return(0);
break;
case '?':
if (sc == 0)
return(0);
break;
case '*':
s--;
do {
if (*p == '\0' || gmatch(s, p))
return(1);
} while (*s++ != '\0');
return(0);
default:
if (sc != (pc&~QUOTE))
return(0);
}
}
return(*s == 0);
}
static char *
cclass(p, sub)
register char *p;
register int sub;
{
register int c, d, not, found;
if ((not = *p == NOT) != 0)
p++;
found = not;
do {
if (*p == '\0')
return((char *)NULL);
c = *p & CMASK;
if (p[1] == '-' && p[2] != ']') {
d = p[2] & CMASK;
p++;
} else
d = c;
if (c == sub || (c <= sub && sub <= d))
found = !not;
} while (*++p != ']');
return(found? p+1: (char *)NULL);
}
/* -------- area.c -------- */
/*
* All memory between (char *)areabot and (char *)(areatop+1) is
* exclusively administered by the area management routines.
* It is assumed that sbrk() and brk() manipulate the high end.
*/
#define sbrk(X) ({ void * __q = (void *)-1; if (brkaddr + (int)(X) < brktop) { __q = brkaddr; brkaddr+=(int)(X); } __q;})
static void
initarea()
{
brkaddr = malloc(65000);
brktop = brkaddr + 65000;
while ((int)sbrk(0) & ALIGN)
sbrk(1);
areabot = (struct region *)sbrk(REGSIZE);
areabot->next = areabot;
areabot->area = BUSY;
areatop = areabot;
areanxt = areabot;
}
char *
getcell(nbytes)
unsigned nbytes;
{
register int nregio;
register struct region *p, *q;
register int i;
if (nbytes == 0) {
puts("getcell(0)");
abort();
} /* silly and defeats the algorithm */
/*
* round upwards and add administration area
*/
nregio = (nbytes+(REGSIZE-1))/REGSIZE + 1;
for (p = areanxt;;) {
if (p->area > areanum) {
/*
* merge free cells
*/
while ((q = p->next)->area > areanum && q != areanxt)
p->next = q->next;
/*
* exit loop if cell big enough
*/
if (q >= p + nregio)
goto found;
}
p = p->next;
if (p == areanxt)
break;
}
i = nregio >= GROWBY ? nregio : GROWBY;
p = (struct region *)sbrk(i * REGSIZE);
if (p == (struct region *)-1)
return((char *)NULL);
p--;
if (p != areatop) {
puts("not contig");
abort(); /* allocated areas are contiguous */
}
q = p + i;
p->next = q;
p->area = FREE;
q->next = areabot;
q->area = BUSY;
areatop = q;
found:
/*
* we found a FREE area big enough, pointed to by 'p', and up to 'q'
*/
areanxt = p + nregio;
if (areanxt < q) {
/*
* split into requested area and rest
*/
if (areanxt+1 > q) {
puts("OOM");
abort(); /* insufficient space left for admin */
}
areanxt->next = q;
areanxt->area = FREE;
p->next = areanxt;
}
p->area = areanum;
return((char *)(p+1));
}
static void
freecell(cp)
char *cp;
{
register struct region *p;
if ((p = (struct region *)cp) != NULL) {
p--;
if (p < areanxt)
areanxt = p;
p->area = FREE;
}
}
static void
freearea(a)
register int a;
{
register struct region *p, *top;
top = areatop;
for (p = areabot; p != top; p = p->next)
if (p->area >= a)
p->area = FREE;
}
static void
setarea(cp,a)
char *cp;
int a;
{
register struct region *p;
if ((p = (struct region *)cp) != NULL)
(p-1)->area = a;
}
int
getarea(cp)
char *cp;
{
return ((struct region*)cp-1)->area;
}
static void
garbage()
{
register struct region *p, *q, *top;
top = areatop;
for (p = areabot; p != top; p = p->next) {
if (p->area > areanum) {
while ((q = p->next)->area > areanum)
p->next = q->next;
areanxt = p;
}
}
#ifdef SHRINKBY
if (areatop >= q + SHRINKBY && q->area > areanum) {
brk((char *)(q+1));
q->next = areabot;
q->area = BUSY;
areatop = q;
}
#endif
}
/* -------- csyn.c -------- */
/*
* shell: syntax (C version)
*/
int
yyparse()
{
startl = 1;
peeksym = 0;
yynerrs = 0;
outtree = c_list();
musthave('\n', 0);
return(yynerrs!=0);
}
static struct op *
pipeline(cf)
int cf;
{
register struct op *t, *p;
register int c;
t = command(cf);
if (t != NULL) {
while ((c = yylex(0)) == '|') {
if ((p = command(CONTIN)) == NULL)
SYNTAXERR;
if (t->type != TPAREN && t->type != TCOM) {
/* shell statement */
t = block(TPAREN, t, NOBLOCK, NOWORDS);
}
t = block(TPIPE, t, p, NOWORDS);
}
peeksym = c;
}
return(t);
}
static struct op *
andor()
{
register struct op *t, *p;
register int c;
t = pipeline(0);
if (t != NULL) {
while ((c = yylex(0)) == LOGAND || c == LOGOR) {
if ((p = pipeline(CONTIN)) == NULL)
SYNTAXERR;
t = block(c == LOGAND? TAND: TOR, t, p, NOWORDS);
}
peeksym = c;
}
return(t);
}
static struct op *
c_list()
{
register struct op *t, *p;
register int c;
t = andor();
if (t != NULL) {
if((peeksym = yylex(0)) == '&')
t = block(TASYNC, t, NOBLOCK, NOWORDS);
while ((c = yylex(0)) == ';' || c == '&' || (multiline && c == '\n')) {
if ((p = andor()) == NULL)
return(t);
if((peeksym = yylex(0)) == '&')
p = block(TASYNC, p, NOBLOCK, NOWORDS);
t = list(t, p);
}
peeksym = c;
}
return(t);
}
static int
synio(cf)
int cf;
{
register struct ioword *iop;
register int i;
register int c;
if ((c = yylex(cf)) != '<' && c != '>') {
peeksym = c;
return(0);
}
i = yylval.i;
musthave(WORD, 0);
iop = io(iounit, i, yylval.cp);
iounit = IODEFAULT;
if (i & IOHERE)
markhere(yylval.cp, iop);
return(1);
}
static void
musthave(c, cf)
int c, cf;
{
if ((peeksym = yylex(cf)) != c)
SYNTAXERR;
peeksym = 0;
}
static struct op *
simple()
{
register struct op *t;
t = NULL;
for (;;) {
switch (peeksym = yylex(0)) {
case '<':
case '>':
(void) synio(0);
break;
case WORD:
if (t == NULL) {
t = newtp();
t->type = TCOM;
}
peeksym = 0;
word(yylval.cp);
break;
default:
return(t);
}
}
}
static struct op *
nested(type, mark)
int type, mark;
{
register struct op *t;
multiline++;
t = c_list();
musthave(mark, 0);
multiline--;
return(block(type, t, NOBLOCK, NOWORDS));
}
static struct op *
command(cf)
int cf;
{
register struct op *t;
struct wdblock *iosave;
register int c;
iosave = iolist;
iolist = NULL;
if (multiline)
cf |= CONTIN;
while (synio(cf))
cf = 0;
switch (c = yylex(cf)) {
default:
peeksym = c;
if ((t = simple()) == NULL) {
if (iolist == NULL)
return((struct op *)NULL);
t = newtp();
t->type = TCOM;
}
break;
case '(':
t = nested(TPAREN, ')');
break;
case '{':
t = nested(TBRACE, '}');
break;
case FOR:
t = newtp();
t->type = TFOR;
musthave(WORD, 0);
startl = 1;
t->str = yylval.cp;
multiline++;
t->words = wordlist();
if ((c = yylex(0)) != '\n' && c != ';')
peeksym = c;
t->left = dogroup(0);
multiline--;
break;
case WHILE:
case UNTIL:
multiline++;
t = newtp();
t->type = c == WHILE? TWHILE: TUNTIL;
t->left = c_list();
t->right = dogroup(1);
t->words = NULL;
multiline--;
break;
case CASE:
t = newtp();
t->type = TCASE;
musthave(WORD, 0);
t->str = yylval.cp;
startl++;
multiline++;
musthave(IN, CONTIN);
startl++;
t->left = caselist();
musthave(ESAC, 0);
multiline--;
break;
case IF:
multiline++;
t = newtp();
t->type = TIF;
t->left = c_list();
t->right = thenpart();
musthave(FI, 0);
multiline--;
break;
}
while (synio(0))
;
t = namelist(t);
iolist = iosave;
return(t);
}
static struct op *
dogroup(onlydone)
int onlydone;
{
register int c;
register struct op *mylist;
c = yylex(CONTIN);
if (c == DONE && onlydone)
return((struct op *)NULL);
if (c != DO)
SYNTAXERR;
mylist = c_list();
musthave(DONE, 0);
return(mylist);
}
static struct op *
thenpart()
{
register int c;
register struct op *t;
if ((c = yylex(0)) != THEN) {
peeksym = c;
return((struct op *)NULL);
}
t = newtp();
t->type = 0;
t->left = c_list();
if (t->left == NULL)
SYNTAXERR;
t->right = elsepart();
return(t);
}
static struct op *
elsepart()
{
register int c;
register struct op *t;
switch (c = yylex(0)) {
case ELSE:
if ((t = c_list()) == NULL)
SYNTAXERR;
return(t);
case ELIF:
t = newtp();
t->type = TELIF;
t->left = c_list();
t->right = thenpart();
return(t);
default:
peeksym = c;
return((struct op *)NULL);
}
}
static struct op *
caselist()
{
register struct op *t;
t = NULL;
while ((peeksym = yylex(CONTIN)) != ESAC)
t = list(t, casepart());
return(t);
}
static struct op *
casepart()
{
register struct op *t;
t = newtp();
t->type = TPAT;
t->words = pattern();
musthave(')', 0);
t->left = c_list();
if ((peeksym = yylex(CONTIN)) != ESAC)
musthave(BREAK, CONTIN);
return(t);
}
static char **
pattern()
{
register int c, cf;
cf = CONTIN;
do {
musthave(WORD, cf);
word(yylval.cp);
cf = 0;
} while ((c = yylex(0)) == '|');
peeksym = c;
word(NOWORD);
return(copyw());
}
static char **
wordlist()
{
register int c;
if ((c = yylex(0)) != IN) {
peeksym = c;
return((char **)NULL);
}
startl = 0;
while ((c = yylex(0)) == WORD)
word(yylval.cp);
word(NOWORD);
peeksym = c;
return(copyw());
}
/*
* supporting functions
*/
static struct op *
list(t1, t2)
register struct op *t1, *t2;
{
if (t1 == NULL)
return(t2);
if (t2 == NULL)
return(t1);
return(block(TLIST, t1, t2, NOWORDS));
}
static struct op *
block(type, t1, t2, wp)
int type;
struct op *t1, *t2;
char **wp;
{
register struct op *t;
t = newtp();
t->type = type;
t->left = t1;
t->right = t2;
t->words = wp;
return(t);
}
static int
rlookup(n)
register char *n;
{
register struct res *rp;
for (rp = restab; rp->r_name; rp++)
if (strcmp(rp->r_name, n) == 0)
return(rp->r_val);
return(0);
}
static struct op *
newtp()
{
register struct op *t;
t = (struct op *)tree(sizeof(*t));
t->type = 0;
t->words = NULL;
t->ioact = NULL;
t->left = NULL;
t->right = NULL;
t->str = NULL;
return(t);
}
static struct op *
namelist(t)
register struct op *t;
{
if (iolist) {
iolist = addword((char *)NULL, iolist);
t->ioact = copyio();
} else
t->ioact = NULL;
if (t->type != TCOM) {
if (t->type != TPAREN && t->ioact != NULL) {
t = block(TPAREN, t, NOBLOCK, NOWORDS);
t->ioact = t->left->ioact;
t->left->ioact = NULL;
}
return(t);
}
word(NOWORD);
t->words = copyw();
return(t);
}
static char **
copyw()
{
register char **wd;
wd = getwords(wdlist);
wdlist = 0;
return(wd);
}
static void
word(cp)
char *cp;
{
wdlist = addword(cp, wdlist);
}
static struct ioword **
copyio()
{
register struct ioword **iop;
iop = (struct ioword **) getwords(iolist);
iolist = 0;
return(iop);
}
static struct ioword *
io(u, f, cp)
int u;
int f;
char *cp;
{
register struct ioword *iop;
iop = (struct ioword *) tree(sizeof(*iop));
iop->io_unit = u;
iop->io_flag = f;
iop->io_name = cp;
iolist = addword((char *)iop, iolist);
return(iop);
}
static void
zzerr()
{
yyerror("syntax error");
}
static void
yyerror(s)
char *s;
{
yynerrs++;
if (interactive && e.iop <= iostack) {
multiline = 0;
while (eofc() == 0 && yylex(0) != '\n')
;
}
err(s);
fail();
}
static int
yylex(cf)
int cf;
{
register int c, c1;
int atstart;
if ((c = peeksym) > 0) {
peeksym = 0;
if (c == '\n')
startl = 1;
return(c);
}
nlseen = 0;
e.linep = line;
atstart = startl;
startl = 0;
yylval.i = 0;
loop:
while ((c = my_getc(0)) == ' ' || c == '\t')
;
switch (c) {
default:
if (any(c, "0123456789")) {
unget(c1 = my_getc(0));
if (c1 == '<' || c1 == '>') {
iounit = c - '0';
goto loop;
}
*e.linep++ = c;
c = c1;
}
break;
case '#':
while ((c = my_getc(0)) != 0 && c != '\n')
;
unget(c);
goto loop;
case 0:
return(c);
case '$':
*e.linep++ = c;
if ((c = my_getc(0)) == '{') {
if ((c = collect(c, '}')) != '\0')
return(c);
goto pack;
}
break;
case '`':
case '\'':
case '"':
if ((c = collect(c, c)) != '\0')
return(c);
goto pack;
case '|':
case '&':
case ';':
if ((c1 = dual(c)) != '\0') {
startl = 1;
return(c1);
}
startl = 1;
return(c);
case '^':
startl = 1;
return('|');
case '>':
case '<':
diag(c);
return(c);
case '\n':
nlseen++;
gethere();
startl = 1;
if (multiline || cf & CONTIN) {
if (interactive && e.iop <= iostack) {
#ifdef BB_FEATURE_COMMAND_EDITING
current_prompt=cprompt->value;
#else
prs(cprompt->value);
#endif
}
if (cf & CONTIN)
goto loop;
}
return(c);
case '(':
case ')':
startl = 1;
return(c);
}
unget(c);
pack:
while ((c = my_getc(0)) != 0 && !any(c, "`$ '\"\t;&<>()|^\n"))
if (e.linep >= elinep)
err("word too long");
else
*e.linep++ = c;
unget(c);
if(any(c, "\"'`$"))
goto loop;
*e.linep++ = '\0';
if (atstart && (c = rlookup(line))!=0) {
startl = 1;
return(c);
}
yylval.cp = strsave(line, areanum);
return(WORD);
}
static int
collect(c, c1)
register int c, c1;
{
char s[2];
*e.linep++ = c;
while ((c = my_getc(c1)) != c1) {
if (c == 0) {
unget(c);
s[0] = c1;
s[1] = 0;
prs("no closing "); yyerror(s);
return(YYERRCODE);
}
if (interactive && c == '\n' && e.iop <= iostack) {
#ifdef BB_FEATURE_COMMAND_EDITING
current_prompt=cprompt->value;
#else
prs(cprompt->value);
#endif
}
*e.linep++ = c;
}
*e.linep++ = c;
return(0);
}
static int
dual(c)
register int c;
{
char s[3];
register char *cp = s;
*cp++ = c;
*cp++ = my_getc(0);
*cp = 0;
if ((c = rlookup(s)) == 0)
unget(*--cp);
return(c);
}
static void
diag(ec)
register int ec;
{
register int c;
c = my_getc(0);
if (c == '>' || c == '<') {
if (c != ec)
zzerr();
yylval.i = ec == '>'? IOWRITE|IOCAT: IOHERE;
c = my_getc(0);
} else
yylval.i = ec == '>'? IOWRITE: IOREAD;
if (c != '&' || yylval.i == IOHERE)
unget(c);
else
yylval.i |= IODUP;
}
static char *
tree(size)
unsigned size;
{
register char *t;
if ((t = getcell(size)) == NULL) {
prs("command line too complicated\n");
fail();
/* NOTREACHED */
}
return(t);
}
/* VARARGS1 */
/* ARGSUSED */
/* -------- exec.c -------- */
/*
* execute tree
*/
static int
execute(t, pin, pout, act)
register struct op *t;
int *pin, *pout;
int act;
{
register struct op *t1;
volatile int i, rv, a;
char *cp, **wp, **wp2;
struct var *vp;
struct brkcon bc;
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &wp;
#endif
if (t == NULL)
return(0);
rv = 0;
a = areanum++;
wp = (wp2 = t->words) != NULL
? eval(wp2, t->type == TCOM ? DOALL : DOALL & ~DOKEY)
: NULL;
switch(t->type) {
case TPAREN:
case TCOM:
{
int child;
rv = forkexec(t, pin, pout, act, wp, &child);
if (child) {
exstat = rv;
leave();
}
}
break;
case TPIPE:
{
int pv[2];
if ((rv = openpipe(pv)) < 0)
break;
pv[0] = remap(pv[0]);
pv[1] = remap(pv[1]);
(void) execute(t->left, pin, pv, 0);
rv = execute(t->right, pv, pout, 0);
}
break;
case TLIST:
(void) execute(t->left, pin, pout, 0);
rv = execute(t->right, pin, pout, 0);
break;
case TASYNC:
{
int hinteractive = interactive;
i = vfork();
if (i != 0) {
interactive = hinteractive;
if (i != -1) {
setval(lookup("!"), putn(i));
if (pin != NULL)
closepipe(pin);
if (interactive) {
prs(putn(i));
prs("\n");
}
} else
rv = -1;
setstatus(rv);
} else {
signal(SIGINT, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
if (interactive)
signal(SIGTERM, SIG_DFL);
interactive = 0;
if (pin == NULL) {
close(0);
open("/dev/null", 0);
}
exit(execute(t->left, pin, pout, FEXEC));
}
}
break;
case TOR:
case TAND:
rv = execute(t->left, pin, pout, 0);
if ((t1 = t->right)!=NULL && (rv == 0) == (t->type == TAND))
rv = execute(t1, pin, pout, 0);
break;
case TFOR:
if (wp == NULL) {
wp = dolv+1;
if ((i = dolc) < 0)
i = 0;
} else {
i = -1;
while (*wp++ != NULL)
;
}
vp = lookup(t->str);
while (setjmp(bc.brkpt))
if (isbreak)
goto broken;
brkset(&bc);
for (t1 = t->left; i-- && *wp != NULL;) {
setval(vp, *wp++);
rv = execute(t1, pin, pout, 0);
}
brklist = brklist->nextlev;
break;
case TWHILE:
case TUNTIL:
while (setjmp(bc.brkpt))
if (isbreak)
goto broken;
brkset(&bc);
t1 = t->left;
while ((execute(t1, pin, pout, 0) == 0) == (t->type == TWHILE))
rv = execute(t->right, pin, pout, 0);
brklist = brklist->nextlev;
break;
case TIF:
case TELIF:
if (t->right != NULL) {
rv = !execute(t->left, pin, pout, 0) ?
execute(t->right->left, pin, pout, 0):
execute(t->right->right, pin, pout, 0);
}
break;
case TCASE:
if ((cp = evalstr(t->str, DOSUB|DOTRIM)) == 0)
cp = "";
if ((t1 = findcase(t->left, cp)) != NULL)
rv = execute(t1, pin, pout, 0);
break;
case TBRACE:
/*
if (iopp = t->ioact)
while (*iopp)
if (iosetup(*iopp++, pin!=NULL, pout!=NULL)) {
rv = -1;
break;
}
*/
if (rv >= 0 && (t1 = t->left))
rv = execute(t1, pin, pout, 0);
break;
}
broken:
t->words = wp2;
isbreak = 0;
freehere(areanum);
freearea(areanum);
areanum = a;
if (interactive && intr) {
closeall();
fail();
}
if ((i = trapset) != 0) {
trapset = 0;
runtrap(i);
}
return(rv);
}
static int
forkexec( register struct op *t, int *pin, int *pout, int act, char **wp, int *pforked)
{
int i, rv;
int (*shcom)() = NULL;
register int f;
char *cp = NULL;
struct ioword **iopp;
int resetsig;
char **owp;
int *hpin = pin;
int *hpout = pout;
int hforked;
char *hwp;
int hinteractive;
int hintr;
struct brkcon * hbrklist;
int hexecflg;
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &pin;
(void) &pout;
(void) &wp;
(void) &shcom;
(void) &cp;
(void) &resetsig;
(void) &owp;
#endif
owp = wp;
resetsig = 0;
*pforked = 0;
rv = -1; /* system-detected error */
if (t->type == TCOM) {
while ((cp = *wp++) != NULL)
;
cp = *wp;
/* strip all initial assignments */
/* not correct wrt PATH=yyy command etc */
if (flag['x'])
echo (cp ? wp: owp);
if (cp == NULL && t->ioact == NULL) {
while ((cp = *owp++) != NULL && assign(cp, COPYV))
;
return(setstatus(0));
}
else if (cp != NULL)
shcom = inbuilt(cp);
}
t->words = wp;
f = act;
if (shcom == NULL && (f & FEXEC) == 0) {
hpin = pin;
hpout = pout;
hforked = *pforked;
hwp = *wp;
hinteractive = interactive;
hintr = intr;
hbrklist = brklist;
hexecflg = execflg;
i = vfork();
if (i != 0) {
/* who wrote this crappy non vfork safe shit? */
pin = hpin;
pout = hpout;
*pforked = hforked;
*wp = hwp;
interactive = hinteractive;
intr = hintr;
brklist = hbrklist;
execflg = hexecflg;
*pforked = 0;
if (i == -1)
return(rv);
if (pin != NULL)
closepipe(pin);
return(pout==NULL? setstatus(waitfor(i,0)): 0);
}
if (interactive) {
signal(SIGINT, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
resetsig = 1;
}
interactive = 0;
intr = 0;
(*pforked)++;
brklist = 0;
execflg = 0;
}
if (owp != NULL)
while ((cp = *owp++) != NULL && assign(cp, COPYV))
if (shcom == NULL)
export(lookup(cp));
#ifdef COMPIPE
if ((pin != NULL || pout != NULL) && shcom != NULL && shcom != doexec) {
err("piping to/from shell builtins not yet done");
return(-1);
}
#endif
if (pin != NULL) {
dup2(pin[0], 0);
closepipe(pin);
}
if (pout != NULL) {
dup2(pout[1], 1);
closepipe(pout);
}
if ((iopp = t->ioact) != NULL) {
if (shcom != NULL && shcom != doexec) {
prs(cp);
err(": cannot redirect shell command");
return(-1);
}
while (*iopp)
if (iosetup(*iopp++, pin!=NULL, pout!=NULL))
return(rv);
}
if (shcom)
return(setstatus((*shcom)(t)));
/* should use FIOCEXCL */
for (i=FDBASE; i<NOFILE; i++)
close(i);
if (resetsig) {
signal(SIGINT, SIG_DFL);
signal(SIGQUIT, SIG_DFL);
}
if (t->type == TPAREN)
exit(execute(t->left, NOPIPE, NOPIPE, FEXEC));
if (wp[0] == NULL)
exit(0);
cp = rexecve(wp[0], wp, makenv());
prs(wp[0]); prs(": "); warn(cp);
if (!execflg)
trap[0] = NULL;
leave();
/* NOTREACHED */
exit(1);
}
/*
* 0< 1> are ignored as required
* within pipelines.
*/
static int
iosetup(iop, pipein, pipeout)
register struct ioword *iop;
int pipein, pipeout;
{
register int u = -1;
char *cp=NULL, *msg;
if (iop->io_unit == IODEFAULT) /* take default */
iop->io_unit = iop->io_flag&(IOREAD|IOHERE)? 0: 1;
if (pipein && iop->io_unit == 0)
return(0);
if (pipeout && iop->io_unit == 1)
return(0);
msg = iop->io_flag&(IOREAD|IOHERE)? "open": "create";
if ((iop->io_flag & IOHERE) == 0) {
cp = iop->io_name;
if ((cp = evalstr(cp, DOSUB|DOTRIM)) == NULL)
return(1);
}
if (iop->io_flag & IODUP) {
if (cp[1] || (!isdigit(*cp) && *cp != '-')) {
prs(cp);
err(": illegal >& argument");
return(1);
}
if (*cp == '-')
iop->io_flag = IOCLOSE;
iop->io_flag &= ~(IOREAD|IOWRITE);
}
switch (iop->io_flag) {
case IOREAD:
u = open(cp, 0);
break;
case IOHERE:
case IOHERE|IOXHERE:
u = herein(iop->io_name, iop->io_flag&IOXHERE);
cp = "here file";
break;
case IOWRITE|IOCAT:
if ((u = open(cp, 1)) >= 0) {
lseek(u, (long)0, 2);
break;
}
case IOWRITE:
u = creat(cp, 0666);
break;
case IODUP:
u = dup2(*cp-'0', iop->io_unit);
break;
case IOCLOSE:
close(iop->io_unit);
return(0);
}
if (u < 0) {
prs(cp);
prs(": cannot ");
warn(msg);
return(1);
} else {
if (u != iop->io_unit) {
dup2(u, iop->io_unit);
close(u);
}
}
return(0);
}
static void
echo(wp)
register char **wp;
{
register int i;
prs("+");
for (i=0; wp[i]; i++) {
if (i)
prs(" ");
prs(wp[i]);
}
prs("\n");
}
static struct op **
find1case(t, w)
struct op *t;
char *w;
{
register struct op *t1;
struct op **tp;
register char **wp, *cp;
if (t == NULL)
return((struct op **)NULL);
if (t->type == TLIST) {
if ((tp = find1case(t->left, w)) != NULL)
return(tp);
t1 = t->right; /* TPAT */
} else
t1 = t;
for (wp = t1->words; *wp;)
if ((cp = evalstr(*wp++, DOSUB)) && gmatch(w, cp))
return(&t1->left);
return((struct op **)NULL);
}
static struct op *
findcase(t, w)
struct op *t;
char *w;
{
register struct op **tp;
return((tp = find1case(t, w)) != NULL? *tp: (struct op *)NULL);
}
/*
* Enter a new loop level (marked for break/continue).
*/
static void
brkset(bc)
struct brkcon *bc;
{
bc->nextlev = brklist;
brklist = bc;
}
/*
* Wait for the last process created.
* Print a message for each process found
* that was killed by a signal.
* Ignore interrupt signals while waiting
* unless `canintr' is true.
*/
static int
waitfor(lastpid, canintr)
register int lastpid;
int canintr;
{
register int pid, rv;
int s;
int oheedint = heedint;
heedint = 0;
rv = 0;
do {
pid = wait(&s);
if (pid == -1) {
if (errno != EINTR || canintr)
break;
} else {
if ((rv = WAITSIG(s)) != 0) {
if (rv < NSIGNAL) {
if (signame[rv] != NULL) {
if (pid != lastpid) {
prn(pid);
prs(": ");
}
prs(signame[rv]);
}
} else {
if (pid != lastpid) {
prn(pid);
prs(": ");
}
prs("Signal "); prn(rv); prs(" ");
}
if (WAITCORE(s))
prs(" - core dumped");
if (rv >= NSIGNAL || signame[rv])
prs("\n");
rv = -1;
} else
rv = WAITVAL(s);
}
} while (pid != lastpid);
heedint = oheedint;
if (intr) {
if (interactive) {
if (canintr)
intr = 0;
} else {
if (exstat == 0) exstat = rv;
onintr(0);
}
}
return(rv);
}
static int
setstatus(s)
register int s;
{
exstat = s;
setval(lookup("?"), putn(s));
return(s);
}
/*
* PATH-searching interface to execve.
* If getenv("PATH") were kept up-to-date,
* execvp might be used.
*/
static char *
rexecve(c, v, envp)
char *c, **v, **envp;
{
register int i;
register char *sp, *tp;
int eacces = 0, asis = 0;
sp = any('/', c)? "": path->value;
asis = *sp == '\0';
while (asis || *sp != '\0') {
asis = 0;
tp = e.linep;
for (; *sp != '\0'; tp++)
if ((*tp = *sp++) == ':') {
asis = *sp == '\0';
break;
}
if (tp != e.linep)
*tp++ = '/';
for (i = 0; (*tp++ = c[i++]) != '\0';)
;
execve(e.linep, v, envp);
switch (errno) {
case ENOEXEC:
*v = e.linep;
tp = *--v;
*v = e.linep;
execve("/bin/sh", v, envp);
*v = tp;
return("no Shell");
case ENOMEM:
return("program too big");
case E2BIG:
return("argument list too long");
case EACCES:
eacces++;
break;
}
}
return(errno==ENOENT ? "not found" : "cannot execute");
}
/*
* Run the command produced by generator `f'
* applied to stream `arg'.
*/
static int
run(argp, f)
struct ioarg *argp;
int (*f)();
{
struct op *otree;
struct wdblock *swdlist;
struct wdblock *siolist;
jmp_buf ev, rt;
xint *ofail;
int rv;
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &rv;
#endif
areanum++;
swdlist = wdlist;
siolist = iolist;
otree = outtree;
ofail = failpt;
rv = -1;
if (newenv(setjmp(errpt = ev)) == 0) {
wdlist = 0;
iolist = 0;
pushio(argp, f);
e.iobase = e.iop;
yynerrs = 0;
if (setjmp(failpt = rt) == 0 && yyparse() == 0)
rv = execute(outtree, NOPIPE, NOPIPE, 0);
quitenv();
}
wdlist = swdlist;
iolist = siolist;
failpt = ofail;
outtree = otree;
freearea(areanum--);
return(rv);
}
/* -------- do.c -------- */
/*
* built-in commands: doX
*/
static int
dolabel()
{
return(0);
}
static int
dochdir(t)
register struct op *t;
{
register char *cp, *er;
if ((cp = t->words[1]) == NULL && (cp = homedir->value) == NULL)
er = ": no home directory";
else if(chdir(cp) < 0)
er = ": bad directory";
else
return(0);
prs(cp != NULL? cp: "cd");
err(er);
return(1);
}
static int
doshift(t)
register struct op *t;
{
register int n;
n = t->words[1]? getn(t->words[1]): 1;
if(dolc < n) {
err("nothing to shift");
return(1);
}
dolv[n] = dolv[0];
dolv += n;
dolc -= n;
setval(lookup("#"), putn(dolc));
return(0);
}
/*
* execute login and newgrp directly
*/
static int
dologin(t)
struct op *t;
{
register char *cp;
if (interactive) {
signal(SIGINT, SIG_DFL);
signal(SIGQUIT, SIG_DFL);
}
cp = rexecve(t->words[0], t->words, makenv());
prs(t->words[0]); prs(": "); err(cp);
return(1);
}
static int
doumask(t)
register struct op *t;
{
register int i, n;
register char *cp;
if ((cp = t->words[1]) == NULL) {
i = umask(0);
umask(i);
for (n=3*4; (n-=3) >= 0;)
putc('0'+((i>>n)&07), stderr);
putc('\n', stderr);
} else {
for (n=0; *cp>='0' && *cp<='9'; cp++)
n = n*8 + (*cp-'0');
umask(n);
}
return(0);
}
static int
doexec(t)
register struct op *t;
{
register int i;
jmp_buf ex;
xint *ofail;
t->ioact = NULL;
for(i = 0; (t->words[i]=t->words[i+1]) != NULL; i++)
;
if (i == 0)
return(1);
execflg = 1;
ofail = failpt;
if (setjmp(failpt = ex) == 0)
execute(t, NOPIPE, NOPIPE, FEXEC);
failpt = ofail;
execflg = 0;
return(1);
}
static int
dodot(t)
struct op *t;
{
register int i;
register char *sp, *tp;
char *cp;
if ((cp = t->words[1]) == NULL)
return(0);
sp = any('/', cp)? ":": path->value;
while (*sp) {
tp = e.linep;
while (*sp && (*tp = *sp++) != ':')
tp++;
if (tp != e.linep)
*tp++ = '/';
for (i = 0; (*tp++ = cp[i++]) != '\0';)
;
if ((i = open(e.linep, 0)) >= 0) {
exstat = 0;
next(remap(i));
return(exstat);
}
}
prs(cp);
err(": not found");
return(-1);
}
static int
dowait(t)
struct op *t;
{
register int i;
register char *cp;
if ((cp = t->words[1]) != NULL) {
i = getn(cp);
if (i == 0)
return(0);
} else
i = -1;
setstatus(waitfor(i, 1));
return(0);
}
static int
doread(t)
struct op *t;
{
register char *cp, **wp;
register int nb = 0;
register int nl = 0;
if (t->words[1] == NULL) {
err("Usage: read name ...");
return(1);
}
for (wp = t->words+1; *wp; wp++) {
for (cp = e.linep; !nl && cp < elinep-1; cp++)
if ((nb = read(0, cp, sizeof(*cp))) != sizeof(*cp) ||
(nl = (*cp == '\n')) ||
(wp[1] && any(*cp, ifs->value)))
break;
*cp = 0;
if (nb <= 0)
break;
setval(lookup(*wp), e.linep);
}
return(nb <= 0);
}
static int
doeval(t)
register struct op *t;
{
return(RUN(awordlist, t->words+1, wdchar));
}
static int
dotrap(t)
register struct op *t;
{
register int n, i;
register int resetsig;
if (t->words[1] == NULL) {
for (i=0; i<=_NSIG; i++)
if (trap[i]) {
prn(i);
prs(": ");
prs(trap[i]);
prs("\n");
}
return(0);
}
resetsig = isdigit(*t->words[1]);
for (i = resetsig ? 1 : 2; t->words[i] != NULL; ++i) {
n = getsig(t->words[i]);
freecell(trap[n]);
trap[n] = 0;
if (!resetsig) {
if (*t->words[1] != '\0') {
trap[n] = strsave(t->words[1], 0);
setsig(n, sig);
} else
setsig(n, SIG_IGN);
} else {
if (interactive)
if (n == SIGINT)
setsig(n, onintr);
else
setsig(n, n == SIGQUIT ? SIG_IGN
: SIG_DFL);
else
setsig(n, SIG_DFL);
}
}
return(0);
}
static int
getsig(s)
char *s;
{
register int n;
if ((n = getn(s)) < 0 || n > _NSIG) {
err("trap: bad signal number");
n = 0;
}
return(n);
}
static void
setsig( register int n, void (*f)(int))
{
if (n == 0)
return;
if (signal(n, SIG_IGN) != SIG_IGN || ourtrap[n]) {
ourtrap[n] = 1;
signal(n, f);
}
}
static int
getn(as)
char *as;
{
register char *s;
register int n, m;
s = as;
m = 1;
if (*s == '-') {
m = -1;
s++;
}
for (n = 0; isdigit(*s); s++)
n = (n*10) + (*s-'0');
if (*s) {
prs(as);
err(": bad number");
}
return(n*m);
}
static int
dobreak(t)
struct op *t;
{
return(brkcontin(t->words[1], 1));
}
static int
docontinue(t)
struct op *t;
{
return(brkcontin(t->words[1], 0));
}
static int
brkcontin(cp, val)
register char *cp;
int val;
{
register struct brkcon *bc;
register int nl;
nl = cp == NULL? 1: getn(cp);
if (nl <= 0)
nl = 999;
do {
if ((bc = brklist) == NULL)
break;
brklist = bc->nextlev;
} while (--nl);
if (nl) {
err("bad break/continue level");
return(1);
}
isbreak = val;
longjmp(bc->brkpt, 1);
/* NOTREACHED */
}
static int
doexit(t)
struct op *t;
{
register char *cp;
execflg = 0;
if ((cp = t->words[1]) != NULL)
setstatus(getn(cp));
leave();
/* NOTREACHED */
return(0);
}
static int
doexport(t)
struct op *t;
{
rdexp(t->words+1, export, EXPORT);
return(0);
}
static int
doreadonly(t)
struct op *t;
{
rdexp(t->words+1, ronly, RONLY);
return(0);
}
static void
rdexp(wp, f, key)
register char **wp;
void (*f)();
int key;
{
if (*wp != NULL) {
for (; *wp != NULL; wp++)
if (checkname(*wp))
(*f)(lookup(*wp));
else
badid(*wp);
} else
putvlist(key, 1);
}
static void
badid(s)
register char *s;
{
prs(s);
err(": bad identifier");
}
static int
doset(t)
register struct op *t;
{
register struct var *vp;
register char *cp;
register int n;
if ((cp = t->words[1]) == NULL) {
for (vp = vlist; vp; vp = vp->next)
varput(vp->name, 1);
return(0);
}
if (*cp == '-') {
/* bad: t->words++; */
for(n = 0; (t->words[n]=t->words[n+1]) != NULL; n++)
;
if (*++cp == 0)
flag['x'] = flag['v'] = 0;
else
for (; *cp; cp++)
switch (*cp) {
case 'e':
if (!interactive)
flag['e']++;
break;
default:
if (*cp>='a' && *cp<='z')
flag[(int)*cp]++;
break;
}
setdash();
}
if (t->words[1]) {
t->words[0] = dolv[0];
for (n=1; t->words[n]; n++)
setarea((char *)t->words[n], 0);
dolc = n-1;
dolv = t->words;
setval(lookup("#"), putn(dolc));
setarea((char *)(dolv-1), 0);
}
return(0);
}
static void
varput(s, out)
register char *s;
int out;
{
if (isalnum(*s)) {
write(out, s, strlen(s));
write(out, "\n", 1);
}
}
/*
* Copyright (c) 1999 Herbert Xu <herbert@debian.org>
* This file contains code for the times builtin.
* $Id: msh.c,v 1.1 2001/06/29 04:57:14 andersen Exp $
*/
static int dotimes ()
{
struct tms buf;
long int clk_tck = sysconf(_SC_CLK_TCK);
times(&buf);
printf("%dm%fs %dm%fs\n%dm%fs %dm%fs\n",
(int) (buf.tms_utime / clk_tck / 60),
((double) buf.tms_utime) / clk_tck,
(int) (buf.tms_stime / clk_tck / 60),
((double) buf.tms_stime) / clk_tck,
(int) (buf.tms_cutime / clk_tck / 60),
((double) buf.tms_cutime) / clk_tck,
(int) (buf.tms_cstime / clk_tck / 60),
((double) buf.tms_cstime) / clk_tck);
return 0;
}
static int (*inbuilt(s))()
register char *s;
{
register struct builtin *bp;
for (bp = builtin; bp->command != NULL; bp++)
if (strcmp(bp->command, s) == 0)
return(bp->fn);
return((int(*)())NULL);
}
/* -------- eval.c -------- */
/*
* ${}
* `command`
* blank interpretation
* quoting
* glob
*/
static char ** eval( char **ap, int f)
{
struct wdblock *wb;
char **wp;
char **wf;
jmp_buf ev;
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &wp;
(void) &ap;
#endif
wp = NULL;
wb = NULL;
wf = NULL;
if (newenv(setjmp(errpt = ev)) == 0) {
while (*ap && isassign(*ap))
expand(*ap++, &wb, f & ~DOGLOB);
if (flag['k']) {
for (wf = ap; *wf; wf++) {
if (isassign(*wf))
expand(*wf, &wb, f & ~DOGLOB);
}
}
for (wb = addword((char *)0, wb); *ap; ap++) {
if (!flag['k'] || !isassign(*ap))
expand(*ap, &wb, f & ~DOKEY);
}
wb = addword((char *)0, wb);
wp = getwords(wb);
quitenv();
} else
gflg = 1;
return(gflg? (char **)NULL: wp);
}
/*
* Make the exported environment from the exported
* names in the dictionary. Keyword assignments
* will already have been done.
*/
static char **
makenv()
{
register struct wdblock *wb;
register struct var *vp;
wb = NULL;
for (vp = vlist; vp; vp = vp->next)
if (vp->status & EXPORT)
wb = addword(vp->name, wb);
wb = addword((char *)0, wb);
return(getwords(wb));
}
static char *
evalstr(cp, f)
register char *cp;
int f;
{
struct wdblock *wb;
wb = NULL;
if (expand(cp, &wb, f)) {
if (wb == NULL || wb->w_nword == 0 || (cp = wb->w_words[0]) == NULL)
cp = "";
DELETE(wb);
} else
cp = NULL;
return(cp);
}
static int
expand( char *cp, register struct wdblock **wbp, int f)
{
jmp_buf ev;
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &cp;
#endif
gflg = 0;
if (cp == NULL)
return(0);
if (!anys("$`'\"", cp) &&
!anys(ifs->value, cp) &&
((f&DOGLOB)==0 || !anys("[*?", cp))) {
cp = strsave(cp, areanum);
if (f & DOTRIM)
unquote(cp);
*wbp = addword(cp, *wbp);
return(1);
}
if (newenv(setjmp(errpt = ev)) == 0) {
PUSHIO(aword, cp, strchar);
e.iobase = e.iop;
while ((cp = blank(f)) && gflg == 0) {
e.linep = cp;
cp = strsave(cp, areanum);
if ((f&DOGLOB) == 0) {
if (f & DOTRIM)
unquote(cp);
*wbp = addword(cp, *wbp);
} else
*wbp = glob(cp, *wbp);
}
quitenv();
} else
gflg = 1;
return(gflg == 0);
}
/*
* Blank interpretation and quoting
*/
static char *
blank(f)
int f;
{
register int c, c1;
register char *sp;
int scanequals, foundequals;
sp = e.linep;
scanequals = f & DOKEY;
foundequals = 0;
loop:
switch (c = subgetc('"', foundequals)) {
case 0:
if (sp == e.linep)
return(0);
*e.linep++ = 0;
return(sp);
default:
if (f & DOBLANK && any(c, ifs->value))
goto loop;
break;
case '"':
case '\'':
scanequals = 0;
if (INSUB())
break;
for (c1 = c; (c = subgetc(c1, 1)) != c1;) {
if (c == 0)
break;
if (c == '\'' || !any(c, "$`\""))
c |= QUOTE;
*e.linep++ = c;
}
c = 0;
}
unget(c);
if (!isalpha(c))
scanequals = 0;
for (;;) {
c = subgetc('"', foundequals);
if (c == 0 ||
f & (DOBLANK && any(c, ifs->value)) ||
(!INSUB() && any(c, "\"'"))) {
scanequals = 0;
unget(c);
if (any(c, "\"'"))
goto loop;
break;
}
if (scanequals) {
if (c == '=') {
foundequals = 1;
scanequals = 0;
}
else if (!isalnum(c))
scanequals = 0;
}
*e.linep++ = c;
}
*e.linep++ = 0;
return(sp);
}
/*
* Get characters, substituting for ` and $
*/
static int
subgetc(ec, quoted)
register int ec;
int quoted;
{
register char c;
again:
c = my_getc(ec);
if (!INSUB() && ec != '\'') {
if (c == '`') {
if (grave(quoted) == 0)
return(0);
e.iop->task = XGRAVE;
goto again;
}
if (c == '$' && (c = dollar(quoted)) == 0) {
e.iop->task = XDOLL;
goto again;
}
}
return(c);
}
/*
* Prepare to generate the string returned by ${} substitution.
*/
static int
dollar(quoted)
int quoted;
{
int otask;
struct io *oiop;
char *dolp;
register char *s, c, *cp=NULL;
struct var *vp;
c = readc();
s = e.linep;
if (c != '{') {
*e.linep++ = c;
if (isalpha(c)) {
while ((c = readc())!=0 && isalnum(c))
if (e.linep < elinep)
*e.linep++ = c;
unget(c);
}
c = 0;
} else {
oiop = e.iop;
otask = e.iop->task;
e.iop->task = XOTHER;
while ((c = subgetc('"', 0))!=0 && c!='}' && c!='\n')
if (e.linep < elinep)
*e.linep++ = c;
if (oiop == e.iop)
e.iop->task = otask;
if (c != '}') {
err("unclosed ${");
gflg++;
return(c);
}
}
if (e.linep >= elinep) {
err("string in ${} too long");
gflg++;
e.linep -= 10;
}
*e.linep = 0;
if (*s)
for (cp = s+1; *cp; cp++)
if (any(*cp, "=-+?")) {
c = *cp;
*cp++ = 0;
break;
}
if (s[1] == 0 && (*s == '*' || *s == '@')) {
if (dolc > 1) {
/* currently this does not distinguish $* and $@ */
/* should check dollar */
e.linep = s;
PUSHIO(awordlist, dolv+1, dolchar);
return(0);
} else { /* trap the nasty ${=} */
s[0] = '1';
s[1] = 0;
}
}
vp = lookup(s);
if ((dolp = vp->value) == null) {
switch (c) {
case '=':
if (isdigit(*s)) {
err("cannot use ${...=...} with $n");
gflg++;
break;
}
setval(vp, cp);
dolp = vp->value;
break;
case '-':
dolp = strsave(cp, areanum);
break;
case '?':
if (*cp == 0) {
prs("missing value for ");
err(s);
} else
err(cp);
gflg++;
break;
}
} else if (c == '+')
dolp = strsave(cp, areanum);
if (flag['u'] && dolp == null) {
prs("unset variable: ");
err(s);
gflg++;
}
e.linep = s;
PUSHIO(aword, dolp, quoted ? qstrchar : strchar);
return(0);
}
/*
* Run the command in `...` and read its output.
*/
static int
grave(quoted)
int quoted;
{
register int i;
char *cp;
int pf[2];
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &cp;
#endif
for (cp = e.iop->argp->aword; *cp != '`'; cp++)
if (*cp == 0) {
err("no closing `");
return(0);
}
if (openpipe(pf) < 0)
return(0);
if ((i = vfork()) == -1) {
closepipe(pf);
err("try again");
return(0);
}
if (i != 0) {
e.iop->argp->aword = ++cp;
close(pf[1]);
PUSHIO(afile, remap(pf[0]), quoted? qgravechar: gravechar);
return(1);
}
*cp = 0;
/* allow trapped signals */
for (i=0; i<=_NSIG; i++)
if (ourtrap[i] && signal(i, SIG_IGN) != SIG_IGN)
signal(i, SIG_DFL);
dup2(pf[1], 1);
closepipe(pf);
flag['e'] = 0;
flag['v'] = 0;
flag['n'] = 0;
cp = strsave(e.iop->argp->aword, 0);
areanum = 1;
freehere(areanum);
freearea(areanum); /* free old space */
e.oenv = NULL;
e.iop = (e.iobase = iostack) - 1;
unquote(cp);
interactive = 0;
PUSHIO(aword, cp, nlchar);
onecommand();
exit(1);
}
static char *
unquote(as)
register char *as;
{
register char *s;
if ((s = as) != NULL)
while (*s)
*s++ &= ~QUOTE;
return(as);
}
/* -------- glob.c -------- */
/*
* glob
*/
#define scopy(x) strsave((x), areanum)
#define BLKSIZ 512
#define NDENT ((BLKSIZ+sizeof(struct dirent)-1)/sizeof(struct dirent))
static struct wdblock *cl, *nl;
static char spcl[] = "[?*";
static struct wdblock *
glob(cp, wb)
char *cp;
struct wdblock *wb;
{
register int i;
register char *pp;
if (cp == 0)
return(wb);
i = 0;
for (pp = cp; *pp; pp++)
if (any(*pp, spcl))
i++;
else if (!any(*pp & ~QUOTE, spcl))
*pp &= ~QUOTE;
if (i != 0) {
for (cl = addword(scopy(cp), (struct wdblock *)0); anyspcl(cl); cl = nl) {
nl = newword(cl->w_nword*2);
for(i=0; i<cl->w_nword; i++) { /* for each argument */
for (pp = cl->w_words[i]; *pp; pp++)
if (any(*pp, spcl)) {
globname(cl->w_words[i], pp);
break;
}
if (*pp == '\0')
nl = addword(scopy(cl->w_words[i]), nl);
}
for(i=0; i<cl->w_nword; i++)
DELETE(cl->w_words[i]);
DELETE(cl);
}
for(i=0; i<cl->w_nword; i++)
unquote(cl->w_words[i]);
glob0((char *)cl->w_words, cl->w_nword, sizeof(char *), xstrcmp);
if (cl->w_nword) {
for (i=0; i<cl->w_nword; i++)
wb = addword(cl->w_words[i], wb);
DELETE(cl);
return(wb);
}
}
wb = addword(unquote(cp), wb);
return(wb);
}
static void
globname(we, pp)
char *we;
register char *pp;
{
register char *np, *cp;
char *name, *gp, *dp;
int k;
DIR *dirp;
struct dirent *de;
char dname[NAME_MAX+1];
struct stat dbuf;
for (np = we; np != pp; pp--)
if (pp[-1] == '/')
break;
for (dp = cp = space((int)(pp-np)+3); np < pp;)
*cp++ = *np++;
*cp++ = '.';
*cp = '\0';
for (gp = cp = space(strlen(pp)+1); *np && *np != '/';)
*cp++ = *np++;
*cp = '\0';
dirp = opendir(dp);
if (dirp == 0) {
DELETE(dp);
DELETE(gp);
return;
}
dname[NAME_MAX] = '\0';
while ((de=readdir(dirp))!=NULL) {
/* XXX Hmmm... What this could be? (abial) */
/*
if (ent[j].d_ino == 0)
continue;
*/
strncpy(dname, de->d_name, NAME_MAX);
if (dname[0] == '.')
if (*gp != '.')
continue;
for(k=0; k<NAME_MAX; k++)
if (any(dname[k], spcl))
dname[k] |= QUOTE;
if (gmatch(dname, gp)) {
name = generate(we, pp, dname, np);
if (*np && !anys(np, spcl)) {
if (stat(name,&dbuf)) {
DELETE(name);
continue;
}
}
nl = addword(name, nl);
}
}
closedir(dirp);
DELETE(dp);
DELETE(gp);
}
/*
* generate a pathname as below.
* start..end1 / middle end
* the slashes come for free
*/
static char *
generate(start1, end1, middle, end)
char *start1;
register char *end1;
char *middle, *end;
{
char *p;
register char *op, *xp;
p = op = space((int)(end1-start1)+strlen(middle)+strlen(end)+2);
for (xp = start1; xp != end1;)
*op++ = *xp++;
for (xp = middle; (*op++ = *xp++) != '\0';)
;
op--;
for (xp = end; (*op++ = *xp++) != '\0';)
;
return(p);
}
static int
anyspcl(wb)
register struct wdblock *wb;
{
register int i;
register char **wd;
wd = wb->w_words;
for (i=0; i<wb->w_nword; i++)
if (anys(spcl, *wd++))
return(1);
return(0);
}
static int
xstrcmp(p1, p2)
char *p1, *p2;
{
return(strcmp(*(char **)p1, *(char **)p2));
}
/* -------- word.c -------- */
static struct wdblock *
newword(nw)
register int nw;
{
register struct wdblock *wb;
wb = (struct wdblock *) space(sizeof(*wb) + nw*sizeof(char *));
wb->w_bsize = nw;
wb->w_nword = 0;
return(wb);
}
static struct wdblock *
addword(wd, wb)
char *wd;
register struct wdblock *wb;
{
register struct wdblock *wb2;
register int nw;
if (wb == NULL)
wb = newword(NSTART);
if ((nw = wb->w_nword) >= wb->w_bsize) {
wb2 = newword(nw * 2);
memcpy((char *)wb2->w_words, (char *)wb->w_words, nw*sizeof(char *));
wb2->w_nword = nw;
DELETE(wb);
wb = wb2;
}
wb->w_words[wb->w_nword++] = wd;
return(wb);
}
static
char **
getwords(wb)
register struct wdblock *wb;
{
register char **wd;
register int nb;
if (wb == NULL)
return((char **)NULL);
if (wb->w_nword == 0) {
DELETE(wb);
return((char **)NULL);
}
wd = (char **) space(nb = sizeof(*wd) * wb->w_nword);
memcpy((char *)wd, (char *)wb->w_words, nb);
DELETE(wb); /* perhaps should done by caller */
return(wd);
}
int (*func)(char *, char *);
int globv;
static void
glob0(a0, a1, a2, a3)
char *a0;
unsigned a1;
int a2;
int (*a3) (char *, char *);
{
func = a3;
globv = a2;
glob1(a0, a0 + a1 * a2);
}
static void
glob1(base, lim)
char *base, *lim;
{
register char *i, *j;
int v2;
char *lptr, *hptr;
int c;
unsigned n;
v2 = globv;
top:
if ((n=(int)(lim-base)) <= v2)
return;
n = v2 * (n / (2*v2));
hptr = lptr = base+n;
i = base;
j = lim-v2;
for(;;) {
if (i < lptr) {
if ((c = (*func)(i, lptr)) == 0) {
glob2(i, lptr -= v2);
continue;
}
if (c < 0) {
i += v2;
continue;
}
}
begin:
if (j > hptr) {
if ((c = (*func)(hptr, j)) == 0) {
glob2(hptr += v2, j);
goto begin;
}
if (c > 0) {
if (i == lptr) {
glob3(i, hptr += v2, j);
i = lptr += v2;
goto begin;
}
glob2(i, j);
j -= v2;
i += v2;
continue;
}
j -= v2;
goto begin;
}
if (i == lptr) {
if (lptr-base >= lim-hptr) {
glob1(hptr+v2, lim);
lim = lptr;
} else {
glob1(base, lptr);
base = hptr+v2;
}
goto top;
}
glob3(j, lptr -= v2, i);
j = hptr -= v2;
}
}
static void
glob2(i, j)
char *i, *j;
{
register char *index1, *index2, c;
int m;
m = globv;
index1 = i;
index2 = j;
do {
c = *index1;
*index1++ = *index2;
*index2++ = c;
} while(--m);
}
static void
glob3(i, j, k)
char *i, *j, *k;
{
register char *index1, *index2, *index3;
int c;
int m;
m = globv;
index1 = i;
index2 = j;
index3 = k;
do {
c = *index1;
*index1++ = *index3;
*index3++ = *index2;
*index2++ = c;
} while(--m);
}
/* -------- io.c -------- */
/*
* shell IO
*/
static int my_getc( int ec)
{
register int c;
if(e.linep > elinep) {
while((c=readc()) != '\n' && c)
;
err("input line too long");
gflg++;
return(c);
}
c = readc();
if (ec != '\'' && e.iop->task != XGRAVE) {
if(c == '\\') {
c = readc();
if (c == '\n' && ec != '\"')
return(my_getc(ec));
c |= QUOTE;
}
}
return(c);
}
static void
unget(c)
int c;
{
if (e.iop >= e.iobase)
e.iop->peekc = c;
}
static int
eofc()
{
return e.iop < e.iobase || (e.iop->peekc == 0 && e.iop->prev == 0);
}
static int
readc()
{
register int c;
for (; e.iop >= e.iobase; e.iop--)
if ((c = e.iop->peekc) != '\0') {
e.iop->peekc = 0;
return(c);
}
else {
if (e.iop->prev != 0) {
if ((c = (*e.iop->iofn)(e.iop->argp, e.iop)) != '\0') {
if (c == -1) {
e.iop++;
continue;
}
if (e.iop == iostack)
ioecho(c);
return(e.iop->prev = c);
}
else if (e.iop->task == XIO && e.iop->prev != '\n') {
e.iop->prev = 0;
if (e.iop == iostack)
ioecho('\n');
return '\n';
}
}
if (e.iop->task == XIO) {
if (multiline)
return e.iop->prev = 0;
if (interactive && e.iop == iostack+1) {
#ifdef BB_FEATURE_COMMAND_EDITING
current_prompt=prompt->value;
#else
prs(prompt->value);
#endif
}
}
}
if (e.iop >= iostack)
return(0);
leave();
/* NOTREACHED */
return(0);
}
static void
ioecho(c)
char c;
{
if (flag['v'])
write(2, &c, sizeof c);
}
static void
pushio(argp, fn)
struct ioarg *argp;
int (*fn)();
{
if (++e.iop >= &iostack[NPUSH]) {
e.iop--;
err("Shell input nested too deeply");
gflg++;
return;
}
e.iop->iofn = fn;
if (argp->afid != AFID_NOBUF)
e.iop->argp = argp;
else {
e.iop->argp = ioargstack + (e.iop - iostack);
*e.iop->argp = *argp;
e.iop->argp->afbuf = e.iop == &iostack[0] ? &mainbuf : &sharedbuf;
if (isatty(e.iop->argp->afile) == 0 &&
(e.iop == &iostack[0] ||
lseek(e.iop->argp->afile, 0L, 1) != -1)) {
if (++bufid == AFID_NOBUF)
bufid = AFID_ID;
e.iop->argp->afid = bufid;
}
}
e.iop->prev = ~'\n';
e.iop->peekc = 0;
e.iop->xchar = 0;
e.iop->nlcount = 0;
if (fn == filechar || fn == linechar)
e.iop->task = XIO;
else if (fn == gravechar || fn == qgravechar)
e.iop->task = XGRAVE;
else
e.iop->task = XOTHER;
}
static struct io *
setbase(ip)
struct io *ip;
{
register struct io *xp;
xp = e.iobase;
e.iobase = ip;
return(xp);
}
/*
* Input generating functions
*/
/*
* Produce the characters of a string, then a newline, then EOF.
*/
static int
nlchar(ap)
register struct ioarg *ap;
{
register int c;
if (ap->aword == NULL)
return(0);
if ((c = *ap->aword++) == 0) {
ap->aword = NULL;
return('\n');
}
return(c);
}
/*
* Given a list of words, produce the characters
* in them, with a space after each word.
*/
static int
wdchar(ap)
register struct ioarg *ap;
{
register char c;
register char **wl;
if ((wl = ap->awordlist) == NULL)
return(0);
if (*wl != NULL) {
if ((c = *(*wl)++) != 0)
return(c & 0177);
ap->awordlist++;
return(' ');
}
ap->awordlist = NULL;
return('\n');
}
/*
* Return the characters of a list of words,
* producing a space between them.
*/
static int
dolchar(ap)
register struct ioarg *ap;
{
register char *wp;
if ((wp = *ap->awordlist++) != NULL) {
PUSHIO(aword, wp, *ap->awordlist == NULL? strchar: xxchar);
return(-1);
}
return(0);
}
static int
xxchar(ap)
register struct ioarg *ap;
{
register int c;
if (ap->aword == NULL)
return(0);
if ((c = *ap->aword++) == '\0') {
ap->aword = NULL;
return(' ');
}
return(c);
}
/*
* Produce the characters from a single word (string).
*/
static int
strchar(ap)
register struct ioarg *ap;
{
register int c;
if (ap->aword == NULL || (c = *ap->aword++) == 0)
return(0);
return(c);
}
/*
* Produce quoted characters from a single word (string).
*/
static int
qstrchar(ap)
register struct ioarg *ap;
{
register int c;
if (ap->aword == NULL || (c = *ap->aword++) == 0)
return(0);
return(c|QUOTE);
}
/*
* Return the characters from a file.
*/
static int
filechar(ap)
register struct ioarg *ap;
{
register int i;
char c;
struct iobuf *bp = ap->afbuf;
if (ap->afid != AFID_NOBUF) {
if ((i = ap->afid != bp->id) || bp->bufp == bp->ebufp) {
if (i)
lseek(ap->afile, ap->afpos, 0);
do {
i = read(ap->afile, bp->buf, sizeof(bp->buf));
} while (i < 0 && errno == EINTR);
if (i <= 0) {
closef(ap->afile);
return 0;
}
bp->id = ap->afid;
bp->ebufp = (bp->bufp = bp->buf) + i;
}
ap->afpos++;
return *bp->bufp++ & 0177;
}
#ifdef BB_FEATURE_COMMAND_EDITING
if (interactive) {
static char mycommand[BUFSIZ];
static int position = 0, size = 0;
while (size == 0 || position >= size) {
cmdedit_read_input(current_prompt, mycommand);
cmdedit_terminate();
size = strlen(mycommand);
position = 0;
}
c = mycommand[position];
position++;
return(c);
} else
#endif
{
do {
i = read(ap->afile, &c, sizeof(c));
} while (i < 0 && errno == EINTR);
return(i == sizeof(c)? c&0177: (closef(ap->afile), 0));
}
}
/*
* Return the characters from a here temp file.
*/
static int
herechar(ap)
register struct ioarg *ap;
{
char c;
if (read(ap->afile, &c, sizeof(c)) != sizeof(c)) {
close(ap->afile);
c = 0;
}
return (c);
}
/*
* Return the characters produced by a process (`...`).
* Quote them if required, and remove any trailing newline characters.
*/
static int
gravechar(ap, iop)
struct ioarg *ap;
struct io *iop;
{
register int c;
if ((c = qgravechar(ap, iop)&~QUOTE) == '\n')
c = ' ';
return(c);
}
static int
qgravechar(ap, iop)
register struct ioarg *ap;
struct io *iop;
{
register int c;
if (iop->xchar) {
if (iop->nlcount) {
iop->nlcount--;
return('\n'|QUOTE);
}
c = iop->xchar;
iop->xchar = 0;
} else if ((c = filechar(ap)) == '\n') {
iop->nlcount = 1;
while ((c = filechar(ap)) == '\n')
iop->nlcount++;
iop->xchar = c;
if (c == 0)
return(c);
iop->nlcount--;
c = '\n';
}
return(c!=0? c|QUOTE: 0);
}
/*
* Return a single command (usually the first line) from a file.
*/
static int
linechar(ap)
register struct ioarg *ap;
{
register int c;
if ((c = filechar(ap)) == '\n') {
if (!multiline) {
closef(ap->afile);
ap->afile = -1; /* illegal value */
}
}
return(c);
}
static void
prs(s)
register char *s;
{
if (*s)
write(2, s, strlen(s));
}
static void
prn(u)
unsigned u;
{
prs(itoa(u, 0));
}
static void
closef(i)
register int i;
{
if (i > 2)
close(i);
}
static void
closeall()
{
register int u;
for (u=NUFILE; u<NOFILE;)
close(u++);
}
/*
* remap fd into Shell's fd space
*/
static int
remap(fd)
register int fd;
{
register int i;
int map[NOFILE];
if (fd < e.iofd) {
for (i=0; i<NOFILE; i++)
map[i] = 0;
do {
map[fd] = 1;
fd = dup(fd);
} while (fd >= 0 && fd < e.iofd);
for (i=0; i<NOFILE; i++)
if (map[i])
close(i);
if (fd < 0)
err("too many files open in shell");
}
return(fd);
}
static int
openpipe(pv)
register int *pv;
{
register int i;
if ((i = pipe(pv)) < 0)
err("can't create pipe - try again");
return(i);
}
static void
closepipe(pv)
register int *pv;
{
if (pv != NULL) {
close(*pv++);
close(*pv);
}
}
/* -------- here.c -------- */
/*
* here documents
*/
static void
markhere(s, iop)
register char *s;
struct ioword *iop;
{
register struct here *h, *lh;
h = (struct here *) space(sizeof(struct here));
if (h == 0)
return;
h->h_tag = evalstr(s, DOSUB);
if (h->h_tag == 0)
return;
h->h_iop = iop;
iop->io_name = 0;
h->h_next = NULL;
if (inhere == 0)
inhere = h;
else
for (lh = inhere; lh!=NULL; lh = lh->h_next)
if (lh->h_next == 0) {
lh->h_next = h;
break;
}
iop->io_flag |= IOHERE|IOXHERE;
for (s = h->h_tag; *s; s++)
if (*s & QUOTE) {
iop->io_flag &= ~ IOXHERE;
*s &= ~ QUOTE;
}
h->h_dosub = iop->io_flag & IOXHERE;
}
static void
gethere()
{
register struct here *h, *hp;
/* Scan here files first leaving inhere list in place */
for (hp = h = inhere; h != NULL; hp = h, h = h->h_next)
readhere(&h->h_iop->io_name, h->h_tag, h->h_dosub? 0: '\'');
/* Make inhere list active - keep list intact for scraphere */
if (hp != NULL) {
hp->h_next = acthere;
acthere = inhere;
inhere = NULL;
}
}
static void
readhere(name, s, ec)
char **name;
register char *s;
int ec;
{
int tf;
char tname[30] = ".msh_XXXXXX";
register int c;
jmp_buf ev;
char myline [LINELIM+1];
char *thenext;
tf = mkstemp(tname);
if (tf < 0)
return;
*name = strsave(tname, areanum);
if (newenv(setjmp(errpt = ev)) != 0)
unlink(tname);
else {
pushio(e.iop->argp, e.iop->iofn);
e.iobase = e.iop;
for (;;) {
if (interactive && e.iop <= iostack) {
#ifdef BB_FEATURE_COMMAND_EDITING
current_prompt=cprompt->value;
#else
prs(cprompt->value);
#endif
}
thenext = myline;
while ((c = my_getc(ec)) != '\n' && c) {
if (ec == '\'')
c &= ~ QUOTE;
if (thenext >= &myline[LINELIM]) {
c = 0;
break;
}
*thenext++ = c;
}
*thenext = 0;
if (strcmp(s, myline) == 0 || c == 0)
break;
*thenext++ = '\n';
write (tf, myline, (int)(thenext-myline));
}
if (c == 0) {
prs("here document `"); prs(s); err("' unclosed");
}
quitenv();
}
close(tf);
}
/*
* open here temp file.
* if unquoted here, expand here temp file into second temp file.
*/
static int
herein(hname, xdoll)
char *hname;
int xdoll;
{
register int hf;
int tf;
#if __GNUC__
/* Avoid longjmp clobbering */
(void) &tf;
#endif
if (hname == 0)
return(-1);
hf = open(hname, 0);
if (hf < 0)
return (-1);
if (xdoll) {
char c;
char tname[30] = ".msh_XXXXXX";
jmp_buf ev;
tf = mkstemp(tname);
if (tf < 0)
return (-1);
if (newenv(setjmp(errpt = ev)) == 0) {
PUSHIO(afile, hf, herechar);
setbase(e.iop);
while ((c = subgetc(0, 0)) != 0) {
c &= ~ QUOTE;
write(tf, &c, sizeof c);
}
quitenv();
} else
unlink(tname);
close(tf);
tf = open(tname, 0);
unlink(tname);
return (tf);
} else
return (hf);
}
static void
scraphere()
{
register struct here *h;
for (h = inhere; h != NULL; h = h->h_next) {
if (h->h_iop && h->h_iop->io_name)
unlink(h->h_iop->io_name);
}
inhere = NULL;
}
/* unlink here temp files before a freearea(area) */
static void
freehere(area)
int area;
{
register struct here *h, *hl;
hl = NULL;
for (h = acthere; h != NULL; h = h->h_next)
if (getarea((char *) h) >= area) {
if (h->h_iop->io_name != NULL)
unlink(h->h_iop->io_name);
if (hl == NULL)
acthere = h->h_next;
else
hl->h_next = h->h_next;
} else
hl = h;
}
/*
* Copyright (c) 1987,1997, Prentice Hall
* All rights reserved.
*
* Redistribution and use of the MINIX operating system in source and
* binary forms, with or without modification, are permitted provided
* that the following conditions are met:
*
* Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* Neither the name of Prentice Hall nor the names of the software
* authors or contributors may be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS, AUTHORS, AND
* CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL PRENTICE HALL OR ANY AUTHORS OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
* OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/