Commit 5c2c0b8b authored by Rémi Denis-Courmont's avatar Rémi Denis-Courmont
Browse files

- Fix various error handling bugs in vlc_execve.

- Use a single pipe rather two pairs
parent 7e784b4d
......@@ -25,11 +25,12 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
#include <vlc/vlc.h>
#include <string.h> /* strdup() */
#include <stdlib.h>
#include <ctype.h>
#include <vlc/vlc.h>
#undef iconv_t
#undef iconv_open
......@@ -49,6 +50,9 @@
# include <unistd.h>
# include <errno.h>
# include <sys/wait.h>
# include <fcntl.h>
# include <sys/socket.h>
# include <sys/poll.h>
#endif
#if defined(WIN32) || defined(UNDER_CE)
......@@ -914,128 +918,122 @@ char **vlc_parse_cmdline( const char *psz_cmdline, int *i_args )
* vlc_execve: Execute an external program with a given environment,
* wait until it finishes and return its standard output
*************************************************************************/
int __vlc_execve( vlc_object_t *p_object, int i_argc, char **ppsz_argv,
char **ppsz_env, char *psz_cwd, char *p_in, int i_in,
char **pp_data, int *pi_data )
int __vlc_execve( vlc_object_t *p_object, int i_argc, char *const *ppsz_argv,
char *const *ppsz_env, const char *psz_cwd,
const char *p_in, size_t i_in,
char **pp_data, size_t *pi_data )
{
#ifdef HAVE_FORK
int pi_stdin[2];
int pi_stdout[2];
pid_t i_child_pid;
# define BUFSIZE 1024
int fds[2], i_status;
pipe( pi_stdin );
pipe( pi_stdout );
if ( (i_child_pid = fork()) == -1 )
{
msg_Err( p_object, "unable to fork (%s)", strerror(errno) );
if (socketpair (AF_LOCAL, SOCK_STREAM, 0, fds))
return -1;
}
if ( i_child_pid == 0 )
{
close(0);
dup(pi_stdin[1]);
close(pi_stdin[0]);
pid_t pid = -1;
if ((fds[0] > 2) && (fds[1] > 2))
pid = fork ();
close(1);
dup(pi_stdout[1]);
close(pi_stdout[0]);
switch (pid)
{
case -1:
msg_Err (p_object, "unable to fork (%s)", strerror (errno));
close (fds[0]);
close (fds[1]);
return -1;
close(2);
case 0:
/* NOTE:
* Like it or not, close can fail (and not only with EBADF)
*/
if ((close (0) == 0) && (close (1) == 0) && (close (2) == 0)
&& (dup (fds[1]) == 0) && (dup (fds[1]) == 1)
&& (open ("/dev/null", O_RDONLY) == 2)
&& ((psz_cwd == NULL) || (chdir (psz_cwd) == 0)))
execve (ppsz_argv[0], ppsz_argv, ppsz_env);
if ( psz_cwd != NULL )
chdir( psz_cwd );
execve( ppsz_argv[0], ppsz_argv, ppsz_env );
exit(1);
exit (1);
}
close(pi_stdin[1]);
close(pi_stdout[1]);
if ( !i_in )
close( pi_stdin[0] );
close (fds[1]);
*pi_data = 0;
if( *pp_data )
free( *pp_data );
if (*pp_data)
free (*pp_data);
*pp_data = NULL;
*pp_data = malloc( 1025 ); /* +1 for \0 */
if( !*pp_data )
return -1;
while ( !p_object->b_die )
if (i_in == 0)
shutdown (fds[0], SHUT_WR);
while (!p_object->b_die)
{
int i_ret, i_status;
fd_set readfds, writefds;
struct timeval tv;
FD_ZERO( &readfds );
FD_ZERO( &writefds );
FD_SET( pi_stdout[0], &readfds );
if ( i_in )
FD_SET( pi_stdin[0], &writefds );
tv.tv_sec = 0;
tv.tv_usec = 10000;
i_ret = select( pi_stdin[0] > pi_stdout[0] ? pi_stdin[0] + 1 :
pi_stdout[0] + 1, &readfds, &writefds, NULL, &tv );
if ( i_ret > 0 )
struct pollfd ufd[1];
memset (ufd, 0, sizeof (ufd));
ufd[0].fd = fds[0];
ufd[0].events = POLLIN;
if (i_in > 0)
ufd[0].events |= POLLOUT;
if (poll (ufd, 1, 10) <= 0)
continue;
if (ufd[0].revents & ~POLLOUT)
{
if ( FD_ISSET( pi_stdout[0], &readfds ) )
{
ssize_t i_read = read( pi_stdout[0], &(*pp_data)[*pi_data],
1024 );
if ( i_read > 0 )
{
*pi_data += i_read;
*pp_data = realloc( *pp_data, *pi_data + 1025 );
}
}
if ( FD_ISSET( pi_stdin[0], &writefds ) )
char *ptr = realloc (*pp_data, *pi_data + BUFSIZE + 1);
if (ptr == NULL)
break; /* safely abort */
*pp_data = ptr;
ssize_t val = read (fds[0], ptr + *pi_data, BUFSIZE);
switch (val)
{
ssize_t i_write = write( pi_stdin[0], p_in, __MIN(i_in, 1024) );
if ( i_write > 0 )
{
p_in += i_write;
i_in -= i_write;
}
if ( !i_in )
close( pi_stdin[0] );
case -1:
case 0:
shutdown (fds[0], SHUT_RD);
break;
default:
*pi_data += val;
}
}
if ( waitpid( i_child_pid, &i_status, WNOHANG ) == i_child_pid )
if (ufd[0].revents & POLLOUT)
{
if ( WIFEXITED( i_status ) )
ssize_t val = write (fds[0], p_in, i_in);
switch (val)
{
if ( WEXITSTATUS( i_status ) )
{
msg_Warn( p_object,
"child %s returned with error code %d",
ppsz_argv[0], WEXITSTATUS( i_status ) );
}
case -1:
case 0:
i_in = 0;
shutdown (fds[0], SHUT_WR);
break;
default:
i_in -= val;
p_in += val;
}
else
{
if ( WIFSIGNALED( i_status ) )
{
msg_Warn( p_object,
"child %s quit on signal %d", ppsz_argv[0],
WTERMSIG( i_status ) );
}
}
if ( i_in )
close( pi_stdin[0] );
close( pi_stdout[0] );
break;
}
}
if ( i_ret < 0 && errno != EINTR )
{
msg_Warn( p_object, "select failed (%s)", strerror(errno) );
}
close (fds[0]);
while (waitpid (pid, &i_status, 0) == -1);
if (WIFEXITED (i_status))
{
i_status = WEXITSTATUS (i_status);
if (i_status)
msg_Warn (p_object, "child %s (PID %d) exited with error code %d",
ppsz_argv[0], (int)pid, i_status);
}
else
if (WIFSIGNALED (i_status)) // <-- this should be redumdant a check
{
i_status = WTERMSIG (i_status);
msg_Warn (p_object, "child %s (PID %d) exited on signal %d (%s)",
ppsz_argv[0], (int)pid, i_status, strsignal (i_status));
}
#elif defined( WIN32 ) && !defined( UNDER_CE )
......@@ -1210,6 +1208,9 @@ int __vlc_execve( vlc_object_t *p_object, int i_argc, char **ppsz_argv,
#endif
if (*pp_data == NULL)
return -1;
(*pp_data)[*pi_data] = '\0';
return 0;
}
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