p/desktop-tools
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

iexec: enable not exitting together with the child

Browse Source
This commit is contained in:
Přemysl Eric Janouch 2023-06-19 18:57:52 +02:00
parent 4cc1baf429
commit 7e30dfb6f0
Signed by: p
GPG Key ID: A0420B94F92B9493
1 changed files with 53 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

77
iexec.c
View File

@ -24,20 +24,35 @@
// This can also work on BSD if someone puts in the effort to support kqueue // This can also work on BSD if someone puts in the effort to support kqueue
#include <sys/inotify.h> #include <sys/inotify.h>
static pid_t g_child; static struct
static bool g_restarting = false; {
static int g_inotify_fd, g_inotify_wd; pid_t child; ///< Watched child or 0
bool exits; ///< Don't restart child when it exits
bool respawn; ///< Respawn child ASAP
bool killing; ///< Waiting for child to die
int inotify_fd, inotify_wd;
}
g;
// Note that this program doesn't queue up file-based restarts
static void static void
handle_inotify_event (const struct inotify_event *e, const char *base) handle_inotify_event (const struct inotify_event *e, const char *base)
{ {
if (e->wd != g_inotify_wd || strcmp (e->name, base)) if (e->wd != g.inotify_wd || strcmp (e->name, base))
return; return;
if (g.child)
{
print_debug ("file changed, killing child"); print_debug ("file changed, killing child");
g_restarting = true; if (kill (g.child, SIGINT))
if (g_child >= 0 && kill (g_child, SIGINT))
print_error ("kill: %s", strerror (errno)); print_error ("kill: %s", strerror (errno));
g.killing = true;
}
else
{
print_debug ("file changed, respawning");
g.respawn = true;
}
} }
static void static void
@ -46,7 +61,7 @@ handle_file_change (const char *base)
char buf[4096]; char buf[4096];
ssize_t len = 0; ssize_t len = 0;
struct inotify_event *e = NULL; struct inotify_event *e = NULL;
while ((len = read (g_inotify_fd, buf, sizeof buf)) > 0) while ((len = read (g.inotify_fd, buf, sizeof buf)) > 0)
for (char *ptr = buf; ptr < buf + len; ptr += sizeof *e + e->len) for (char *ptr = buf; ptr < buf + len; ptr += sizeof *e + e->len)
handle_inotify_event ((e = (struct inotify_event *) buf), base); handle_inotify_event ((e = (struct inotify_event *) buf), base);
} }
@ -54,9 +69,9 @@ handle_file_change (const char *base)
static void static void
spawn (char *argv[]) spawn (char *argv[])
{ {
if ((g_child = fork ()) == -1) if ((g.child = fork ()) == -1)
exit_fatal ("fork: %s", strerror (errno)); exit_fatal ("fork: %s", strerror (errno));
else if (g_child) else if (g.child)
return; return;
// A linker can create spurious CLOSE_WRITEs, wait until it's executable // A linker can create spurious CLOSE_WRITEs, wait until it's executable
@ -69,23 +84,22 @@ spawn (char *argv[])
} }
static bool static bool
check_child_death (char *argv[]) check_child_death (void)
{ {
if (waitpid (g_child, NULL, WNOHANG) != g_child) int status = 0;
if (waitpid (g.child, &status, WNOHANG) != g.child)
return true; return true;
if (!g_restarting) g.child = 0;
if (!g.killing)
{ {
print_debug ("child died on its own, not respawning"); print_debug ("child died on its own, not respawning");
return false; return g.exits;
} }
else
{ g.killing = false;
print_debug ("child died on request, respawning"); print_debug ("child died on request, respawning");
spawn (argv); return g.respawn = true;
g_restarting = false;
return true;
}
} }
static void static void
@ -102,6 +116,7 @@ main (int argc, char *argv[])
static const struct opt opts[] = static const struct opt opts[] =
{ {
{ 'f', "file", "PATH", 0, "watch this path rather than the program" }, { 'f', "file", "PATH", 0, "watch this path rather than the program" },
{ 'e', "exits", NULL, 0, "allow the program to exit on its own" },
{ 'd', "debug", NULL, 0, "run in debug mode" }, { 'd', "debug", NULL, 0, "run in debug mode" },
{ 'h', "help", NULL, 0, "display this help and exit" }, { 'h', "help", NULL, 0, "display this help and exit" },
{ 'V', "version", NULL, 0, "output version information and exit" }, { 'V', "version", NULL, 0, "output version information and exit" },
@ -121,6 +136,9 @@ main (int argc, char *argv[])
case 'f': case 'f':
target = optarg; target = optarg;
break; break;
case 'e':
g.exits = true;
break;
case 'd': case 'd':
g_debug_mode = true; g_debug_mode = true;
break; break;
@ -164,25 +182,30 @@ main (int argc, char *argv[])
char *path = NULL; char *path = NULL;
char *dir = dirname ((path = xstrdup (target))); char *dir = dirname ((path = xstrdup (target)));
if ((g_inotify_fd = inotify_init1 (IN_NONBLOCK)) < 0) if ((g.inotify_fd = inotify_init1 (IN_NONBLOCK)) < 0)
exit_fatal ("inotify_init1: %s", strerror (errno)); exit_fatal ("inotify_init1: %s", strerror (errno));
if ((g_inotify_wd = inotify_add_watch (g_inotify_fd, if ((g.inotify_wd = inotify_add_watch (g.inotify_fd,
dir, IN_MOVED_TO | IN_CLOSE_WRITE)) < 0) dir, IN_MOVED_TO | IN_CLOSE_WRITE)) < 0)
exit_fatal ("inotify_add_watch: %s", strerror (errno)); exit_fatal ("inotify_add_watch: %s", strerror (errno));
free (path); free (path);
char *base = basename ((path = xstrdup (target))); char *base = basename ((path = xstrdup (target)));
spawn (argv); g.respawn = true;
do do
{ {
fd_set r; FD_SET (g_inotify_fd, &r); if (g.respawn)
(void) pselect (g_inotify_fd + 1, &r, NULL, NULL, NULL, &orig); {
spawn (argv);
g.respawn = false;
}
fd_set r; FD_SET (g.inotify_fd, &r);
(void) pselect (g.inotify_fd + 1, &r, NULL, NULL, NULL, &orig);
handle_file_change (base); handle_file_change (base);
} }
while (check_child_death (argv)); while (check_child_death ());
free (path); free (path);
close (g_inotify_fd); xclose (g.inotify_fd);
return EXIT_SUCCESS; return EXIT_SUCCESS;
} }