perl: unlock mutex on error

[collectd.git] / src / perl.c

diff --git a/src/perl.c b/src/perl.c
index 924cb63..d247dc0 100644 (file)
--- a/src/perl.c
+++ b/src/perl.c
@@ -510,7 +510,6 @@ static int av2notification_meta (pTHX_ AV *array, notification_meta_t **meta)
                if (NULL == (tmp = hv_fetch (hash, "value", 5, 0))) {
                        log_warn ("av2notification_meta: Skipping invalid "
                                        "meta information.");
-                       free ((*m)->name);
                        free (*m);
                        continue;
                }
@@ -1203,7 +1202,10 @@ static void c_ithread_destructor (void *arg)
 
        /* the ithread no longer exists */
        if (NULL == t)
+       {
+               pthread_mutex_unlock (&perl_threads->mutex);
                return;
+       }
 
        c_ithread_destroy (ithread);
 
@@ -1644,15 +1646,15 @@ static XS (Collectd_plugin_dispatch_values)
 
        values = ST (/* stack index = */ 0);
 
+       if (NULL == values)
+               XSRETURN_EMPTY;
+
        /* Make sure the argument is a hash reference. */
        if (! (SvROK (values) && (SVt_PVHV == SvTYPE (SvRV (values))))) {
                log_err ("Collectd::plugin_dispatch_values: Invalid values.");
                XSRETURN_EMPTY;
        }
 
-       if (NULL == values)
-               XSRETURN_EMPTY;
-
        ret = pplugin_dispatch_values (aTHX_ (HV *)SvRV (values));
 
        if (0 == ret)
@@ -1946,6 +1948,11 @@ static int perl_read (void)
                aTHX = t->interp;
        }
 
+       /* Assert that we're not running as the base thread. Otherwise, we might
+        * run into concurrency issues with c_ithread_create(). See
+        * https://github.com/collectd/collectd/issues/9 for details. */
+       assert (aTHX != perl_threads->head->interp);
+
        log_debug ("perl_read: c_ithread: interp = %p (active threads: %i)",
                        aTHX, perl_threads->number_of_threads);
        return pplugin_call_all (aTHX_ PLUGIN_READ);
@@ -1954,6 +1961,7 @@ static int perl_read (void)
 static int perl_write (const data_set_t *ds, const value_list_t *vl,
                user_data_t __attribute__((unused)) *user_data)
 {
+       int status;
        dTHX;
 
        if (NULL == perl_threads)
@@ -1969,9 +1977,20 @@ static int perl_write (const data_set_t *ds, const value_list_t *vl,
                aTHX = t->interp;
        }
 
+       /* Lock the base thread if this is not called from one of the read threads
+        * to avoid race conditions with c_ithread_create(). See
+        * https://github.com/collectd/collectd/issues/9 for details. */
+       if (aTHX == perl_threads->head->interp)
+               pthread_mutex_lock (&perl_threads->mutex);
+
        log_debug ("perl_write: c_ithread: interp = %p (active threads: %i)",
                        aTHX, perl_threads->number_of_threads);
-       return pplugin_call_all (aTHX_ PLUGIN_WRITE, ds, vl);
+       status = pplugin_call_all (aTHX_ PLUGIN_WRITE, ds, vl);
+
+       if (aTHX == perl_threads->head->interp)
+               pthread_mutex_unlock (&perl_threads->mutex);
+
+       return status;
 } /* static int perl_write (const data_set_t *, const value_list_t *) */
 
 static void perl_log (int level, const char *msg,
@@ -1992,7 +2011,17 @@ static void perl_log (int level, const char *msg,
                aTHX = t->interp;
        }
 
+       /* Lock the base thread if this is not called from one of the read threads
+        * to avoid race conditions with c_ithread_create(). See
+        * https://github.com/collectd/collectd/issues/9 for details. */
+       if (aTHX == perl_threads->head->interp)
+               pthread_mutex_lock (&perl_threads->mutex);
+
        pplugin_call_all (aTHX_ PLUGIN_LOG, level, msg);
+
+       if (aTHX == perl_threads->head->interp)
+               pthread_mutex_unlock (&perl_threads->mutex);
+
        return;
 } /* static void perl_log (int, const char *) */
 
@@ -2120,6 +2149,9 @@ static int g_pv_set (pTHX_ SV *var, MAGIC *mg)
 
 static int g_interval_get (pTHX_ SV *var, MAGIC *mg)
 {
+       log_warn ("Accessing $interval_g is deprecated (and might not "
+                       "give the desired results) - plugin_get_interval() should "
+                       "be used instead.");
        sv_setnv (var, CDTIME_T_TO_DOUBLE (interval_g));
        return 0;
 } /* static int g_interval_get (pTHX_ SV *, MAGIC *) */
@@ -2127,6 +2159,9 @@ static int g_interval_get (pTHX_ SV *var, MAGIC *mg)
 static int g_interval_set (pTHX_ SV *var, MAGIC *mg)
 {
        double nv = (double)SvNV (var);
+       log_warn ("Accessing $interval_g is deprecated (and might not "
+                       "give the desired results) - plugin_get_interval() should "
+                       "be used instead.");
        interval_g = DOUBLE_TO_CDTIME_T (nv);
        return 0;
 } /* static int g_interval_set (pTHX_ SV *, MAGIC *) */
@@ -2477,7 +2512,10 @@ static int perl_config (oconfig_item_t *ci)
                int current_status = 0;
 
                if (NULL != perl_threads)
-                       aTHX = PERL_GET_CONTEXT;
+               {
+                       if ((aTHX = PERL_GET_CONTEXT) == NULL)
+                               return -1;
+               }
 
                if (0 == strcasecmp (c->key, "LoadPlugin"))
                        current_status = perl_config_loadplugin (aTHX_ c);