freebsd-dev/bin/sh/main.c
Jilles Tjoelker 3835f47c7e sh: Remove special code for shell scripts without magic number.
These are called "shell procedures" in the source.

If execve() failed with [ENOEXEC], the shell would reinitialize itself
and execute the program as a script. This requires a fair amount of code
which is not frequently used (most scripts have a #! magic number).
Therefore just execute a new instance of sh (_PATH_BSHELL) to run the
script.
2011-02-04 22:47:55 +00:00

334 lines
7.0 KiB
C

/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 THE REGENTS 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.
*/
#ifndef lint
static char const copyright[] =
"@(#) Copyright (c) 1991, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)main.c 8.6 (Berkeley) 5/28/95";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <stdio.h>
#include <signal.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <locale.h>
#include <errno.h>
#include "shell.h"
#include "main.h"
#include "mail.h"
#include "options.h"
#include "output.h"
#include "parser.h"
#include "nodes.h"
#include "expand.h"
#include "eval.h"
#include "jobs.h"
#include "input.h"
#include "trap.h"
#include "var.h"
#include "show.h"
#include "memalloc.h"
#include "error.h"
#include "init.h"
#include "mystring.h"
#include "exec.h"
#include "cd.h"
int rootpid;
int rootshell;
struct jmploc main_handler;
static void read_profile(const char *);
static char *find_dot_file(char *);
/*
* Main routine. We initialize things, parse the arguments, execute
* profiles if we're a login shell, and then call cmdloop to execute
* commands. The setjmp call sets up the location to jump to when an
* exception occurs. When an exception occurs the variable "state"
* is used to figure out how far we had gotten.
*/
int
main(int argc, char *argv[])
{
struct stackmark smark;
volatile int state;
char *shinit;
(void) setlocale(LC_ALL, "");
state = 0;
if (setjmp(main_handler.loc)) {
switch (exception) {
case EXEXEC:
exitstatus = exerrno;
break;
case EXERROR:
exitstatus = 2;
break;
default:
break;
}
if (state == 0 || iflag == 0 || ! rootshell)
exitshell(exitstatus);
reset();
if (exception == EXINT)
out2fmt_flush("\n");
popstackmark(&smark);
FORCEINTON; /* enable interrupts */
if (state == 1)
goto state1;
else if (state == 2)
goto state2;
else if (state == 3)
goto state3;
else
goto state4;
}
handler = &main_handler;
#ifdef DEBUG
opentrace();
trputs("Shell args: "); trargs(argv);
#endif
rootpid = getpid();
rootshell = 1;
init();
setstackmark(&smark);
procargs(argc, argv);
pwd_init(iflag);
if (iflag)
chkmail(1);
if (argv[0] && argv[0][0] == '-') {
state = 1;
read_profile("/etc/profile");
state1:
state = 2;
if (privileged == 0)
read_profile(".profile");
else
read_profile("/etc/suid_profile");
}
state2:
state = 3;
if (!privileged && iflag) {
if ((shinit = lookupvar("ENV")) != NULL && *shinit != '\0') {
state = 3;
read_profile(shinit);
}
}
state3:
state = 4;
if (minusc) {
evalstring(minusc, sflag ? 0 : EV_EXIT);
}
if (sflag || minusc == NULL) {
state4: /* XXX ??? - why isn't this before the "if" statement */
cmdloop(1);
}
exitshell(exitstatus);
/*NOTREACHED*/
return 0;
}
/*
* Read and execute commands. "Top" is nonzero for the top level command
* loop; it turns on prompting if the shell is interactive.
*/
void
cmdloop(int top)
{
union node *n;
struct stackmark smark;
int inter;
int numeof = 0;
TRACE(("cmdloop(%d) called\n", top));
setstackmark(&smark);
for (;;) {
if (pendingsigs)
dotrap();
inter = 0;
if (iflag && top) {
inter++;
showjobs(1, SHOWJOBS_DEFAULT);
chkmail(0);
flushout(&output);
}
n = parsecmd(inter);
/* showtree(n); DEBUG */
if (n == NEOF) {
if (!top || numeof >= 50)
break;
if (!stoppedjobs()) {
if (!Iflag)
break;
out2fmt_flush("\nUse \"exit\" to leave shell.\n");
}
numeof++;
} else if (n != NULL && nflag == 0) {
job_warning = (job_warning == 2) ? 1 : 0;
numeof = 0;
evaltree(n, 0);
}
popstackmark(&smark);
setstackmark(&smark);
if (evalskip != 0) {
if (evalskip == SKIPFILE)
evalskip = 0;
break;
}
}
popstackmark(&smark);
}
/*
* Read /etc/profile or .profile. Return on error.
*/
static void
read_profile(const char *name)
{
int fd;
INTOFF;
if ((fd = open(name, O_RDONLY)) >= 0)
setinputfd(fd, 1);
INTON;
if (fd < 0)
return;
cmdloop(0);
popfile();
}
/*
* Read a file containing shell functions.
*/
void
readcmdfile(const char *name)
{
int fd;
INTOFF;
if ((fd = open(name, O_RDONLY)) >= 0)
setinputfd(fd, 1);
else
error("Can't open %s: %s", name, strerror(errno));
INTON;
cmdloop(0);
popfile();
}
/*
* Take commands from a file. To be compatible we should do a path
* search for the file, which is necessary to find sub-commands.
*/
static char *
find_dot_file(char *basename)
{
static char localname[FILENAME_MAX+1];
char *fullname;
const char *path = pathval();
struct stat statb;
/* don't try this for absolute or relative paths */
if( strchr(basename, '/'))
return basename;
while ((fullname = padvance(&path, basename)) != NULL) {
strcpy(localname, fullname);
stunalloc(fullname);
if ((stat(fullname, &statb) == 0) && S_ISREG(statb.st_mode))
return localname;
}
return basename;
}
int
dotcmd(int argc, char **argv)
{
char *filename, *fullname;
if (argc < 2)
error("missing filename");
exitstatus = 0;
/*
* Because we have historically not supported any options,
* only treat "--" specially.
*/
filename = argc > 2 && strcmp(argv[1], "--") == 0 ? argv[2] : argv[1];
fullname = find_dot_file(filename);
setinputfile(fullname, 1);
commandname = fullname;
cmdloop(0);
popfile();
return exitstatus;
}
int
exitcmd(int argc, char **argv)
{
if (stoppedjobs())
return 0;
if (argc > 1)
exitshell(number(argv[1]));
else
exitshell_savedstatus();
}