X-Git-Url: https://git.octo.it/?p=collectd.git;a=blobdiff_plain;f=src%2Fdaemon%2Fplugin.c;h=4b7a58ec76e48a6033a096001c592e36d04ef26f;hp=3bf183d9c066934ecbfd664ef1c25e75d1c1920c;hb=f9d2c85e5459dfedbb1e3c09307556a74d5dc3bd;hpb=b165cd13cd30a30ac830df1f6f6fbd52474a6f64

diff --git a/src/daemon/plugin.c b/src/daemon/plugin.c
index 3bf183d9..4b7a58ec 100644
--- a/src/daemon/plugin.c
+++ b/src/daemon/plugin.c
@@ -191,16 +191,21 @@ static int plugin_update_internal_statistics(void) { /* {{{ */
   return 0;
 } /* }}} int plugin_update_internal_statistics */
 
-static void destroy_callback(callback_func_t *cf) /* {{{ */
+static void free_userdata(user_data_t const *ud) /* {{{ */
 {
-  if (cf == NULL)
+  if (ud == NULL)
     return;
 
-  if ((cf->cf_udata.data != NULL) && (cf->cf_udata.free_func != NULL)) {
-    cf->cf_udata.free_func(cf->cf_udata.data);
-    cf->cf_udata.data = NULL;
-    cf->cf_udata.free_func = NULL;
+  if ((ud->data != NULL) && (ud->free_func != NULL)) {
+    ud->free_func(ud->data);
   }
+} /* }}} void free_userdata */
+
+static void destroy_callback(callback_func_t *cf) /* {{{ */
+{
+  if (cf == NULL)
+    return;
+  free_userdata(&cf->cf_udata);
   sfree(cf);
 } /* }}} void destroy_callback */
 
@@ -345,6 +350,7 @@ static int create_register_callback(llist_t **list, /* {{{ */
 
   cf = calloc(1, sizeof(*cf));
   if (cf == NULL) {
+    free_userdata(ud);
     ERROR("plugin: create_register_callback: calloc failed.");
     return -1;
   }
@@ -383,50 +389,44 @@ static int plugin_unregister(llist_t *list, const char *name) /* {{{ */
   return 0;
 } /* }}} int plugin_unregister */
 
-/*
- * (Try to) load the shared object `file'. Won't complain if it isn't a shared
- * object, but it will bitch about a shared object not having a
- * ``module_register'' symbol..
- */
-static int plugin_load_file(const char *file, _Bool global) {
-  void (*reg_handle)(void);
-
+/* plugin_load_file loads the shared object "file" and calls its
+ * "module_register" function. Returns zero on success, non-zero otherwise. */
+static int plugin_load_file(char const *file, _Bool global) {
   int flags = RTLD_NOW;
   if (global)
     flags |= RTLD_GLOBAL;
 
   void *dlh = dlopen(file, flags);
-
   if (dlh == NULL) {
     char errbuf[1024] = "";
 
-    ssnprintf(errbuf, sizeof(errbuf),
-              "dlopen (\"%s\") failed: %s. "
-              "The most common cause for this problem is "
-              "missing dependencies. Use ldd(1) to check "
-              "the dependencies of the plugin "
-              "/ shared object.",
-              file, dlerror());
-
-    ERROR("%s", errbuf);
-    /* Make sure this is printed to STDERR in any case, but also
-     * make sure it's printed only once. */
-    if (list_log != NULL)
-      fprintf(stderr, "ERROR: %s\n", errbuf);
+    snprintf(errbuf, sizeof(errbuf),
+             "dlopen(\"%s\") failed: %s. "
+             "The most common cause for this problem is missing dependencies. "
+             "Use ldd(1) to check the dependencies of the plugin / shared "
+             "object.",
+             file, dlerror());
+
+    /* This error is printed to STDERR unconditionally. If list_log is NULL,
+     * plugin_log() will also print to STDERR. We avoid duplicate output by
+     * checking that the list of log handlers, list_log, is not NULL. */
+    fprintf(stderr, "ERROR: %s\n", errbuf);
+    if (list_log != NULL) {
+      ERROR("%s", errbuf);
+    }
 
-    return 1;
+    return ENOENT;
   }
 
-  reg_handle = (void (*)(void))dlsym(dlh, "module_register");
+  void (*reg_handle)(void) = dlsym(dlh, "module_register");
   if (reg_handle == NULL) {
-    WARNING("Couldn't find symbol \"module_register\" in \"%s\": %s\n", file,
-            dlerror());
+    ERROR("Couldn't find symbol \"module_register\" in \"%s\": %s\n", file,
+          dlerror());
     dlclose(dlh);
-    return -1;
+    return ENOENT;
   }
 
   (*reg_handle)();
-
   return 0;
 }
 
@@ -604,9 +604,7 @@ static void set_thread_name(pthread_t tid, char const *name) {
 #if defined(HAVE_PTHREAD_SETNAME_NP)
   int status = pthread_setname_np(tid, n);
   if (status != 0) {
-    char errbuf[1024];
-    ERROR("set_thread_name(\"%s\"): %s", n,
-          sstrerror(status, errbuf, sizeof(errbuf)));
+    ERROR("set_thread_name(\"%s\"): %s", n, STRERROR(status));
   }
 #else /* if defined(HAVE_PTHREAD_SET_NAME_NP) */
   pthread_set_name_np(tid, n);
@@ -632,15 +630,14 @@ static void start_read_threads(size_t num) /* {{{ */
                                 /* attr = */ NULL, plugin_read_thread,
                                 /* arg = */ NULL);
     if (status != 0) {
-      char errbuf[1024];
-      ERROR("plugin: start_read_threads: pthread_create failed "
-            "with status %i (%s).",
-            status, sstrerror(status, errbuf, sizeof(errbuf)));
+      ERROR("plugin: start_read_threads: pthread_create failed with status %i "
+            "(%s).",
+            status, STRERROR(status));
       return;
     }
 
     char name[THREAD_NAME_MAX];
-    ssnprintf(name, sizeof(name), "reader#%zu", read_threads_num);
+    snprintf(name, sizeof(name), "reader#%zu", read_threads_num);
     set_thread_name(read_threads[read_threads_num], name);
 
     read_threads_num++;
@@ -839,15 +836,14 @@ static void start_write_threads(size_t num) /* {{{ */
                                 /* attr = */ NULL, plugin_write_thread,
                                 /* arg = */ NULL);
     if (status != 0) {
-      char errbuf[1024];
-      ERROR("plugin: start_write_threads: pthread_create failed "
-            "with status %i (%s).",
-            status, sstrerror(status, errbuf, sizeof(errbuf)));
+      ERROR("plugin: start_write_threads: pthread_create failed with status %i "
+            "(%s).",
+            status, STRERROR(status));
       return;
     }
 
     char name[THREAD_NAME_MAX];
-    ssnprintf(name, sizeof(name), "writer#%zu", write_threads_num);
+    snprintf(name, sizeof(name), "writer#%zu", write_threads_num);
     set_thread_name(write_threads[write_threads_num], name);
 
     write_threads_num++;
@@ -996,16 +992,14 @@ int plugin_load(char const *plugin_name, _Bool global) {
 
   /* `cpu' should not match `cpufreq'. To solve this we add `.so' to the
    * type when matching the filename */
-  status = ssnprintf(typename, sizeof(typename), "%s.so", plugin_name);
+  status = snprintf(typename, sizeof(typename), "%s.so", plugin_name);
   if ((status < 0) || ((size_t)status >= sizeof(typename))) {
     WARNING("plugin_load: Filename too long: \"%s.so\"", plugin_name);
     return -1;
   }
 
   if ((dh = opendir(dir)) == NULL) {
-    char errbuf[1024];
-    ERROR("plugin_load: opendir (%s) failed: %s", dir,
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("plugin_load: opendir (%s) failed: %s", dir, STRERRNO);
     return -1;
   }
 
@@ -1013,16 +1007,14 @@ int plugin_load(char const *plugin_name, _Bool global) {
     if (strcasecmp(de->d_name, typename))
       continue;
 
-    status = ssnprintf(filename, sizeof(filename), "%s/%s", dir, de->d_name);
+    status = snprintf(filename, sizeof(filename), "%s/%s", dir, de->d_name);
     if ((status < 0) || ((size_t)status >= sizeof(filename))) {
       WARNING("plugin_load: Filename too long: \"%s/%s\"", dir, de->d_name);
       continue;
     }
 
     if (lstat(filename, &statbuf) == -1) {
-      char errbuf[1024];
-      WARNING("plugin_load: stat (\"%s\") failed: %s", filename,
-              sstrerror(errno, errbuf, sizeof(errbuf)));
+      WARNING("plugin_load: stat (\"%s\") failed: %s", filename, STRERRNO);
       continue;
     } else if (!S_ISREG(statbuf.st_mode)) {
       /* don't follow symlinks */
@@ -1120,8 +1112,7 @@ static int plugin_insert_read(read_func_t *rf) {
   if (le != NULL) {
     pthread_mutex_unlock(&read_lock);
     WARNING("The read function \"%s\" is already registered. "
-            "Check for duplicate \"LoadPlugin\" lines "
-            "in your configuration!",
+            "Check for duplicates in your configuration!",
             rf->rf_name);
     return EINVAL;
   }
@@ -1186,6 +1177,7 @@ int plugin_register_complex_read(const char *group, const char *name,
 
   rf = calloc(1, sizeof(*rf));
   if (rf == NULL) {
+    free_userdata(user_data);
     ERROR("plugin_register_complex_read: calloc failed.");
     return ENOMEM;
   }
@@ -1211,6 +1203,7 @@ int plugin_register_complex_read(const char *group, const char *name,
 
   status = plugin_insert_read(rf);
   if (status != 0) {
+    free_userdata(&rf->rf_udata);
     sfree(rf->rf_name);
     sfree(rf);
   }
@@ -1303,11 +1296,7 @@ int plugin_register_flush(const char *name, plugin_flush_cb callback,
         });
 
     sfree(flush_name);
-    if (status != 0) {
-      sfree(cb->name);
-      sfree(cb);
-      return status;
-    }
+    return status;
   }
 
   return 0;
@@ -1319,8 +1308,7 @@ int plugin_register_missing(const char *name, plugin_missing_cb callback,
 } /* int plugin_register_missing */
 
 int plugin_register_shutdown(const char *name, int (*callback)(void)) {
-  return create_register_callback(&list_shutdown, name, (void *)callback,
-                                  NULL);
+  return create_register_callback(&list_shutdown, name, (void *)callback, NULL);
 } /* int plugin_register_shutdown */
 
 static void plugin_free_data_sets(void) {
@@ -1871,23 +1859,16 @@ int plugin_shutdown_all(void) {
 
 int plugin_dispatch_missing(const value_list_t *vl) /* {{{ */
 {
-  llentry_t *le;
-
   if (list_missing == NULL)
     return 0;
 
-  le = llist_head(list_missing);
+  llentry_t *le = llist_head(list_missing);
   while (le != NULL) {
-    callback_func_t *cf;
-    plugin_missing_cb callback;
-    plugin_ctx_t old_ctx;
-    int status;
-
-    cf = le->value;
-    old_ctx = plugin_set_ctx(cf->cf_ctx);
-    callback = cf->cf_callback;
+    callback_func_t *cf = le->value;
+    plugin_ctx_t old_ctx = plugin_set_ctx(cf->cf_ctx);
+    plugin_missing_cb callback = cf->cf_callback;
 
-    status = (*callback)(vl, &cf->cf_udata);
+    int status = (*callback)(vl, &cf->cf_udata);
     plugin_set_ctx(old_ctx);
     if (status != 0) {
       if (status < 0) {
@@ -1909,8 +1890,6 @@ static int plugin_dispatch_values_internal(value_list_t *vl) {
   int status;
   static c_complain_t no_write_complaint = C_COMPLAIN_INIT_STATIC;
 
-  data_set_t *ds;
-
   _Bool free_meta_data = 0;
 
   assert(vl != NULL);
@@ -1946,6 +1925,7 @@ static int plugin_dispatch_values_internal(value_list_t *vl) {
     return -1;
   }
 
+  data_set_t *ds = NULL;
   if (c_avl_get(data_sets, vl->type, (void *)&ds) != 0) {
     char ident[6 * DATA_MAX_NAME_LEN];
 
@@ -2098,10 +2078,9 @@ int plugin_dispatch_values(value_list_t const *vl) {
 
   status = plugin_write_enqueue(vl);
   if (status != 0) {
-    char errbuf[1024];
-    ERROR("plugin_dispatch_values: plugin_write_enqueue failed "
-          "with status %i (%s).",
-          status, sstrerror(status, errbuf, sizeof(errbuf)));
+    ERROR("plugin_dispatch_values: plugin_write_enqueue failed with status %i "
+          "(%s).",
+          status, STRERROR(status));
     return status;
   }
 
@@ -2468,9 +2447,7 @@ static plugin_ctx_t *plugin_ctx_create(void) {
 
   ctx = malloc(sizeof(*ctx));
   if (ctx == NULL) {
-    char errbuf[1024];
-    ERROR("Failed to allocate plugin context: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("Failed to allocate plugin context: %s", STRERRNO);
     return NULL;
   }