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/*
* Utility routines.
*
* Copyright (C) 2010 ABRT team
* Copyright (C) 2010 RedHat Inc
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "libreport.h"
static char *concat_str_vector(char **strings)
{
if (!strings[0])
return xzalloc(1); // returns ""
unsigned len = 0;
char **spp = strings;
while (*spp)
len += strlen(*spp++) + 1;
char *result = xmalloc(len);
char *r = result;
spp = strings;
while (*spp) {
r = stpcpy(r, *spp++);
*r++ = ' ';
}
*--r = '\0';
return result;
}
/* Returns pid */
pid_t fork_execv_on_steroids(int flags,
char **argv,
int *pipefds,
char **env_vec,
const char *dir,
uid_t uid)
{
pid_t child;
/* Reminder: [0] is read end, [1] is write end */
int pipe_to_child[2];
int pipe_fm_child[2];
/* Sanitize flags */
if (!pipefds)
flags &= ~(EXECFLG_INPUT | EXECFLG_OUTPUT);
if (flags & EXECFLG_INPUT)
xpipe(pipe_to_child);
if (flags & EXECFLG_OUTPUT)
xpipe(pipe_fm_child);
fflush(NULL);
child = fork();
if (child == -1) {
perror_msg_and_die("fork");
}
if (child == 0) {
/* Child */
if (dir)
xchdir(dir);
if (flags & EXECFLG_SETGUID) {
struct passwd* pw = getpwuid(uid);
gid_t gid = pw ? pw->pw_gid : uid;
setgroups(1, &gid);
xsetregid(gid, gid);
xsetreuid(uid, uid);
}
if (env_vec) {
/* Note: we use the glibc extension that putenv("var")
* *unsets* $var if "var" string has no '=' */
while (*env_vec)
putenv(*env_vec++);
}
/* Play with stdio descriptors */
if (flags & EXECFLG_INPUT) {
xmove_fd(pipe_to_child[0], STDIN_FILENO);
close(pipe_to_child[1]);
} else if (flags & EXECFLG_INPUT_NUL) {
xmove_fd(xopen("/dev/null", O_RDWR), STDIN_FILENO);
}
if (flags & EXECFLG_OUTPUT) {
xmove_fd(pipe_fm_child[1], STDOUT_FILENO);
close(pipe_fm_child[0]);
} else if (flags & EXECFLG_OUTPUT_NUL) {
xmove_fd(xopen("/dev/null", O_RDWR), STDOUT_FILENO);
}
/* This should be done BEFORE stderr redirect */
VERB1 {
char *r = concat_str_vector(argv);
log("Executing: %s", r);
free(r);
}
if (flags & EXECFLG_ERR2OUT) {
/* Want parent to see errors in the same stream */
xdup2(STDOUT_FILENO, STDERR_FILENO);
} else if (flags & EXECFLG_ERR_NUL) {
xmove_fd(xopen("/dev/null", O_RDWR), STDERR_FILENO);
}
if (flags & EXECFLG_SETSID)
setsid();
execvp(argv[0], argv);
if (!(flags & EXECFLG_QUIET))
perror_msg("Can't execute '%s'", argv[0]);
exit(127); /* shell uses this exit code in this case */
}
if (flags & EXECFLG_INPUT) {
close(pipe_to_child[0]);
pipefds[1] = pipe_to_child[1];
}
if (flags & EXECFLG_OUTPUT) {
close(pipe_fm_child[1]);
pipefds[0] = pipe_fm_child[0];
}
return child;
}
char *run_in_shell_and_save_output(int flags,
const char *cmd,
const char *dir,
size_t *size_p)
{
flags |= EXECFLG_OUTPUT;
flags &= ~EXECFLG_INPUT;
const char *argv[] = { "/bin/sh", "-c", cmd, NULL };
int pipeout[2];
pid_t child = fork_execv_on_steroids(flags, (char **)argv, pipeout,
/*env_vec:*/ NULL, dir, /*uid (unused):*/ 0);
size_t pos = 0;
char *result = NULL;
while (1) {
result = (char*) xrealloc(result, pos + 4*1024 + 1);
size_t sz = safe_read(pipeout[0], result + pos, 4*1024);
if (sz <= 0) {
break;
}
pos += sz;
}
result[pos] = '\0';
if (size_p)
*size_p = pos;
close(pipeout[0]);
waitpid(child, NULL, 0);
return result;
}
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