shadow/libmisc/shell.c
Serge Hallyn f93cf255d4 Update licensing info
Closes #238

Update all files to list SPDX license shortname.  Most files are
BSD 3 clause license.

The exceptions are:

serge@sl ~/src/shadow$ git grep SPDX-License | grep -v BSD-3-Clause
contrib/atudel:# SPDX-License-Identifier: BSD-4-Clause
lib/tcbfuncs.c: * SPDX-License-Identifier: 0BSD
libmisc/salt.c: * SPDX-License-Identifier: Unlicense
src/login_nopam.c: * SPDX-License-Identifier: Unlicense
src/nologin.c: * SPDX-License-Identifier: BSD-2-Clause
src/vipw.c: * SPDX-License-Identifier: GPL-2.0-or-later

Signed-off-by: Serge Hallyn <serge@hallyn.com>
2021-12-23 19:36:50 -06:00

81 lines
1.9 KiB
C

/*
* SPDX-FileCopyrightText: 1989 - 1991, Julianne Frances Haugh
* SPDX-FileCopyrightText: 1996 - 1998, Marek Michałkiewicz
* SPDX-FileCopyrightText: 2003 - 2006, Tomasz Kłoczko
* SPDX-FileCopyrightText: 2009 , Nicolas François
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <config.h>
#ident "$Id$"
#include <stdio.h>
#include <errno.h>
#include "prototypes.h"
#include "defines.h"
extern char **newenvp;
extern size_t newenvc;
/*
* shell - execute the named program
*
* shell begins by trying to figure out what argv[0] is going to
* be for the named process. The user may pass in that argument,
* or it will be the last pathname component of the file with a
* '-' prepended.
* Then, it executes the named file.
*/
int shell (const char *file, /*@null@*/const char *arg, char *const envp[])
{
char arg0[1024];
int err;
if (file == (char *) 0) {
errno = EINVAL;
return errno;
}
/*
* The argv[0]'th entry is usually the path name, but
* for various reasons the invoker may want to override
* that. So, we determine the 0'th entry only if they
* don't want to tell us what it is themselves.
*/
if (arg == (char *) 0) {
(void) snprintf (arg0, sizeof arg0, "-%s", Basename ((char *) file));
arg0[sizeof arg0 - 1] = '\0';
arg = arg0;
}
/*
* First we try the direct approach. The system should be
* able to figure out what we are up to without too much
* grief.
*/
(void) execle (file, arg, (char *) 0, envp);
err = errno;
if (access (file, R_OK|X_OK) == 0) {
/*
* Assume this is a shell script (with no shebang).
* Interpret it with /bin/sh
*/
(void) execle (SHELL, "sh", "-", file, (char *)0, envp);
err = errno;
}
/*
* Obviously something is really wrong - I can't figure out
* how to execute this stupid shell, so I might as well give
* up in disgust ...
*/
(void) snprintf (arg0, sizeof arg0, _("Cannot execute %s"), file);
errno = err;
perror (arg0);
return err;
}