diff options
Diffstat (limited to 'libnetdata/popen/popen.c')
| -rw-r--r-- | libnetdata/popen/popen.c | 106 |
1 files changed, 48 insertions, 58 deletions
diff --git a/libnetdata/popen/popen.c b/libnetdata/popen/popen.c index 5ed74ae95..783c74a51 100644 --- a/libnetdata/popen/popen.c +++ b/libnetdata/popen/popen.c @@ -5,11 +5,13 @@ // ---------------------------------------------------------------------------- // popen with tracking -static pthread_mutex_t netdata_popen_tracking_mutex; -static bool netdata_popen_tracking_enabled = false; +static pthread_mutex_t netdata_popen_tracking_mutex = NETDATA_MUTEX_INITIALIZER; struct netdata_popen { pid_t pid; + bool reaped; + siginfo_t infop; + int waitid_ret; struct netdata_popen *next; struct netdata_popen *prev; }; @@ -18,29 +20,20 @@ static struct netdata_popen *netdata_popen_root = NULL; // myp_add_lock takes the lock if we're tracking. static void netdata_popen_tracking_lock(void) { - if(!netdata_popen_tracking_enabled) - return; - netdata_mutex_lock(&netdata_popen_tracking_mutex); } // myp_add_unlock release the lock if we're tracking. static void netdata_popen_tracking_unlock(void) { - if(!netdata_popen_tracking_enabled) - return; - netdata_mutex_unlock(&netdata_popen_tracking_mutex); } // myp_add_locked adds pid if we're tracking. // myp_add_lock must have been called previously. static void netdata_popen_tracking_add_pid_unsafe(pid_t pid) { - if(!netdata_popen_tracking_enabled) - return; - struct netdata_popen *mp; - mp = mallocz(sizeof(struct netdata_popen)); + mp = callocz(1, sizeof(struct netdata_popen)); mp->pid = pid; DOUBLE_LINKED_LIST_PREPEND_ITEM_UNSAFE(netdata_popen_root, mp, prev, next); @@ -48,12 +41,9 @@ static void netdata_popen_tracking_add_pid_unsafe(pid_t pid) { // myp_del deletes pid if we're tracking. static void netdata_popen_tracking_del_pid(pid_t pid) { - if(!netdata_popen_tracking_enabled) - return; - struct netdata_popen *mp; - netdata_mutex_lock(&netdata_popen_tracking_mutex); + netdata_popen_tracking_lock(); DOUBLE_LINKED_LIST_FOREACH_FORWARD(netdata_popen_root, mp, prev, next) { if(unlikely(mp->pid == pid)) @@ -65,34 +55,15 @@ static void netdata_popen_tracking_del_pid(pid_t pid) { freez(mp); } else - error("Cannot find pid %d.", pid); - - netdata_mutex_unlock(&netdata_popen_tracking_mutex); -} + error("POPEN: Cannot find pid %d.", pid); -// netdata_popen_tracking_init() should be called by apps which act as init -// (pid 1) so that processes created by mypopen and mypopene -// are tracked. This enables the reaper to ignore processes -// which will be handled internally, by calling myp_reap, to -// avoid issues with already reaped processes during wait calls. -// -// Callers should call myp_free() to clean up resources. -void netdata_popen_tracking_init(void) { - info("process tracking enabled."); - netdata_popen_tracking_enabled = true; - - if (netdata_mutex_init(&netdata_popen_tracking_mutex) != 0) - fatal("netdata_popen_tracking_init() mutex init failed."); + netdata_popen_tracking_unlock(); } // myp_free cleans up any resources allocated for process // tracking. void netdata_popen_tracking_cleanup(void) { - if(!netdata_popen_tracking_enabled) - return; - - netdata_mutex_lock(&netdata_popen_tracking_mutex); - netdata_popen_tracking_enabled = false; + netdata_popen_tracking_lock(); while(netdata_popen_root) { struct netdata_popen *mp = netdata_popen_root; @@ -100,26 +71,45 @@ void netdata_popen_tracking_cleanup(void) { freez(mp); } - netdata_mutex_unlock(&netdata_popen_tracking_mutex); + netdata_popen_tracking_unlock(); } -// myp_reap returns 1 if pid should be reaped, 0 otherwise. -int netdata_popen_tracking_pid_shoud_be_reaped(pid_t pid) { - if(!netdata_popen_tracking_enabled) - return 0; +int netdata_waitid(idtype_t idtype, id_t id, siginfo_t *infop, int options) { + struct netdata_popen *mp = NULL; - netdata_mutex_lock(&netdata_popen_tracking_mutex); + if(idtype == P_PID && id != 0) { + // the caller is asking to waitid() for a specific child pid - int ret = 1; - struct netdata_popen *mp; - DOUBLE_LINKED_LIST_FOREACH_FORWARD(netdata_popen_root, mp, prev, next) { - if(unlikely(mp->pid == pid)) { - ret = 0; - break; + netdata_popen_tracking_lock(); + DOUBLE_LINKED_LIST_FOREACH_FORWARD(netdata_popen_root, mp, prev, next) { + if(unlikely(mp->pid == (pid_t)id)) + break; } + + if(!mp) + netdata_popen_tracking_unlock(); } - netdata_mutex_unlock(&netdata_popen_tracking_mutex); + int ret; + if(mp && mp->reaped) { + // we have already reaped this child + ret = mp->waitid_ret; + *infop = mp->infop; + } + else { + // we haven't reaped this child yet + ret = waitid(idtype, id, infop, options); + + if(mp && !mp->reaped) { + mp->reaped = true; + mp->infop = *infop; + mp->waitid_ret = ret; + } + } + + if(mp) + netdata_popen_tracking_unlock(); + return ret; } @@ -404,7 +394,7 @@ int netdata_pclose(FILE *fp_child_input, FILE *fp_child_output, pid_t pid) { errno = 0; - ret = waitid(P_PID, (id_t) pid, &info, WEXITED); + ret = netdata_waitid(P_PID, (id_t) pid, &info, WEXITED); netdata_popen_tracking_del_pid(pid); if (ret != -1) { @@ -415,8 +405,12 @@ int netdata_pclose(FILE *fp_child_input, FILE *fp_child_output, pid_t pid) { return(info.si_status); case CLD_KILLED: - if(info.si_status == 15) { - info("child pid %d killed by signal %d.", info.si_pid, info.si_status); + if(info.si_status == SIGTERM) { + info("child pid %d killed by SIGTERM", info.si_pid); + return(0); + } + else if(info.si_status == SIGPIPE) { + info("child pid %d killed by SIGPIPE.", info.si_pid); return(0); } else { @@ -450,7 +444,3 @@ int netdata_pclose(FILE *fp_child_input, FILE *fp_child_output, pid_t pid) { return 0; } - -int netdata_spawn_waitpid(pid_t pid) { - return netdata_pclose(NULL, NULL, pid); -} |