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mirror of git://github.com/lxc/lxc synced 2025-08-30 23:59:37 +00:00

utils: duplicate stderr as well in lxc_popen()

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
This commit is contained in:
Christian Brauner
2017-09-13 05:25:22 +02:00
parent b68c6a71d4
commit 3f32320757

View File

@@ -472,6 +472,7 @@ const char** lxc_va_arg_list_to_argv_const(va_list ap, size_t skip)
extern struct lxc_popen_FILE *lxc_popen(const char *command)
{
int ret;
struct lxc_popen_FILE *fp = NULL;
int parent_end = -1, child_end = -1;
int pipe_fds[2];
@@ -491,24 +492,40 @@ extern struct lxc_popen_FILE *lxc_popen(const char *command)
if (child_pid == 0) {
/* child */
int child_std_end = STDOUT_FILENO;
close(parent_end);
if (child_end != child_std_end) {
if (child_end != STDOUT_FILENO) {
/* dup2() doesn't dup close-on-exec flag */
dup2(child_end, child_std_end);
/* it's safe not to close child_end here
* as it's marked close-on-exec anyway
*/
ret = dup2(child_end, STDOUT_FILENO);
if (ret < 0)
WARN("Failed to duplicate stdout fd");
} else {
/*
* The descriptor is already the one we will use.
* But it must not be marked close-on-exec.
* Undo the effects.
*/
if (fcntl(child_end, F_SETFD, 0) != 0) {
ret = fcntl(child_end, F_SETFD, 0);
if (ret < 0) {
SYSERROR("Failed to remove FD_CLOEXEC from fd.");
exit(127);
}
}
if (child_end != STDERR_FILENO) {
/* dup2() doesn't dup close-on-exec flag */
ret = dup2(child_end, STDERR_FILENO);
if (ret < 0)
WARN("Failed to duplicate stdout fd");
} else {
/*
* The descriptor is already the one we will use.
* But it must not be marked close-on-exec.
* Undo the effects.
*/
ret = fcntl(child_end, F_SETFD, 0);
if (ret < 0) {
SYSERROR("Failed to remove FD_CLOEXEC from fd.");
exit(127);
}