misc: add cloexec_fds_from() helper function

Move logic to set file descriptors to a cloexec_fds_from() function in
misc.c so it can be shared by both supervisor-daemon and
start-stop-daemon, and hide the details behind.
This commit is contained in:
Natanael Copa 2023-08-30 13:17:07 +02:00 committed by William Hubbs
parent 5bfb592d75
commit c199c5cf6e
3 changed files with 31 additions and 20 deletions

View File

@ -15,6 +15,11 @@
* except according to the terms contained in the LICENSE file.
*/
#ifdef HAVE_CLOSE_RANGE
/* For close_range() */
# define _GNU_SOURCE
#endif
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
@ -500,3 +505,25 @@ pid_t get_pid(const char *applet,const char *pidfile)
return pid;
}
#ifndef HAVE_CLOSE_RANGE
static inline int close_range(int first RC_UNUSED,
int last RC_UNUSED,
unsigned int flags RC_UNUSED)
{
return -1;
}
#endif
#ifndef CLOSE_RANGE_CLOEXEC
# define CLOSE_RANGE_CLOEXEC (1U << 2)
#endif
void
cloexec_fds_from(int first)
{
int i;
if (close_range(first, UINT_MAX, CLOSE_RANGE_CLOEXEC) < 0) {
for (i = getdtablesize() - 1; i >= first; --i)
fcntl(i, F_SETFD, FD_CLOEXEC);
}
}

View File

@ -73,4 +73,6 @@ void from_time_t(char *time_string, time_t tv);
time_t to_time_t(char *timestring);
pid_t get_pid(const char *applet, const char *pidfile);
void cloexec_fds_from(int);
#endif

View File

@ -22,11 +22,6 @@
#define ONE_SECOND 1000000000
#define ONE_MS 1000000
#ifdef HAVE_CLOSE_RANGE
/* For close_range() */
# define _GNU_SOURCE
#endif
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
@ -203,18 +198,6 @@ static inline int ioprio_set(int which RC_UNUSED, int who RC_UNUSED,
}
#endif
#ifndef CLOSE_RANGE_CLOEXEC
# define CLOSE_RANGE_CLOEXEC (1U << 2)
#endif
#ifndef HAVE_CLOSE_RANGE
static inline int close_range(int first RC_UNUSED,
int last RC_UNUSED,
unsigned int flags RC_UNUSED)
{
return -1;
}
#endif
static void cleanup(void)
{
free(changeuser);
@ -582,9 +565,8 @@ RC_NORETURN static void child_process(char *exec, char **argv)
if (redirect_stderr || rc_yesno(getenv("EINFO_QUIET")))
dup2(stderr_fd, STDERR_FILENO);
if (close_range(3, UINT_MAX, CLOSE_RANGE_CLOEXEC) < 0)
for (i = getdtablesize() - 1; i >= 3; --i)
fcntl(i, F_SETFD, FD_CLOEXEC);
cloexec_fds_from(3);
cmdline = make_cmdline(argv);
syslog(LOG_INFO, "Child command line: %s", cmdline);
free(cmdline);