diff options
| -rw-r--r-- | main/asterisk.c | 20 | ||||
| -rw-r--r-- | utils/astcanary.c | 20 |
2 files changed, 22 insertions, 18 deletions
diff --git a/main/asterisk.c b/main/asterisk.c index 39940ebf5..427ddf6aa 100644 --- a/main/asterisk.c +++ b/main/asterisk.c @@ -276,7 +276,6 @@ static int restartnow; static pthread_t consolethread = AST_PTHREADT_NULL; static int canary_pid = 0; static char canary_filename[128]; -static int canary_pipe = -1; static char randompool[256]; @@ -3495,15 +3494,6 @@ int main(int argc, char *argv[]) /* Spawning of astcanary must happen AFTER the call to daemon(3) */ if (isroot && ast_opt_high_priority) { - int cpipe[2]; - - /* PIPE signal ensures that astcanary dies when Asterisk dies */ - if (pipe(cpipe)) { - fprintf(stderr, "Unable to open pipe for canary process: %s\n", strerror(errno)); - exit(1); - } - canary_pipe = cpipe[0]; - snprintf(canary_filename, sizeof(canary_filename), "%s/alt.asterisk.canary.tweet.tweet.tweet", ast_config_AST_RUN_DIR); /* Don't let the canary child kill Asterisk, if it dies immediately */ @@ -3511,18 +3501,17 @@ int main(int argc, char *argv[]) canary_pid = fork(); if (canary_pid == 0) { - char canary_binary[128], *lastslash; + char canary_binary[128], *lastslash, ppid[12]; /* Reset signal handler */ signal(SIGCHLD, SIG_DFL); signal(SIGPIPE, SIG_DFL); - dup2(cpipe[1], 0); - close(cpipe[1]); ast_close_fds_above_n(0); ast_set_priority(0); + snprintf(ppid, sizeof(ppid), "%d", (int) getpid()); - execlp("astcanary", "astcanary", canary_filename, (char *)NULL); + execlp("astcanary", "astcanary", canary_filename, ppid, (char *)NULL); /* If not found, try the same path as used to execute asterisk */ ast_copy_string(canary_binary, argv[0], sizeof(canary_binary)); @@ -3535,12 +3524,11 @@ int main(int argc, char *argv[]) _exit(1); } else if (canary_pid > 0) { pthread_t dont_care; - close(cpipe[1]); ast_pthread_create_detached(&dont_care, NULL, canary_thread, NULL); } /* Kill the canary when we exit */ - atexit(canary_exit); + ast_register_atexit(canary_exit); } if (ast_event_init()) { diff --git a/utils/astcanary.c b/utils/astcanary.c index aa13c5656..bcf2abb69 100644 --- a/utils/astcanary.c +++ b/utils/astcanary.c @@ -87,9 +87,25 @@ static const char explanation[] = int main(int argc, char *argv[]) { int fd; + pid_t parent; + + if (argc < 3) { + fprintf(stderr, "Usage: %s <monitor-filename> <ppid>\n", argv[0]); + exit(1); + } + /* Run at normal priority */ setpriority(PRIO_PROCESS, 0, 0); - for (;;) { + + /*!\note + * See http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap03.html#tag_03_265 + * for a justification of this approach. The PPID after the creator dies in Linux and + * most other Unix-like systems will be 1, but this is not strictly the case. The POSIX + * specification allows it to be an implementation-defined system process. However, it + * most certainly will not be the original parent PID, which makes the following code + * POSIX-compliant. + */ + for (parent = atoi(argv[2]); parent == getppid() ;) { /* Update the modification times (checked from Asterisk) */ if (utime(argv[1], NULL)) { /* Recreate the file if it doesn't exist */ @@ -108,7 +124,7 @@ int main(int argc, char *argv[]) sleep(5); } - /* Never reached */ + /* Exit when the parent dies */ return 0; } |