Run clang-format after removing ssnprintf

[collectd.git] / src / write_prometheus.c

diff --git a/src/write_prometheus.c b/src/write_prometheus.c
index 43a60fc..eac0d68 100644 (file)
--- a/src/write_prometheus.c
+++ b/src/write_prometheus.c
@@ -37,7 +37,7 @@
 #include <microhttpd.h>
 
 #ifndef PROMETHEUS_DEFAULT_STALENESS_DELTA
-#define PROMETHEUS_DEFAULT_STALENESS_DELTA TIME_T_TO_CDTIME_T(300)
+#define PROMETHEUS_DEFAULT_STALENESS_DELTA TIME_T_TO_CDTIME_T_STATIC(300)
 #endif
 
 #define VARINT_UINT32_BYTES 5
@@ -98,6 +98,43 @@ static void format_protobuf(ProtobufCBuffer *buffer) {
   pthread_mutex_unlock(&metrics_lock);
 }
 
+static char const *escape_label_value(char *buffer, size_t buffer_size,
+                                      char const *value) {
+  /* shortcut for values that don't need escaping. */
+  if (strpbrk(value, "\n\"\\") == NULL)
+    return value;
+
+  size_t value_len = strlen(value);
+  size_t buffer_len = 0;
+
+  for (size_t i = 0; i < value_len; i++) {
+    switch (value[i]) {
+    case '\n':
+    case '"':
+    case '\\':
+      if ((buffer_size - buffer_len) < 3) {
+        break;
+      }
+      buffer[buffer_len] = '\\';
+      buffer[buffer_len + 1] = (value[i] == '\n') ? 'n' : value[i];
+      buffer_len += 2;
+      break;
+
+    default:
+      if ((buffer_size - buffer_len) < 2) {
+        break;
+      }
+      buffer[buffer_len] = value[i];
+      buffer_len++;
+      break;
+    }
+  }
+
+  assert(buffer_len < buffer_size);
+  buffer[buffer_len] = 0;
+  return buffer;
+}
+
 /* format_labels formats a metric's labels in Prometheus-compatible format. This
  * format looks like this:
  *
@@ -109,16 +146,22 @@ static char *format_labels(char *buffer, size_t buffer_size,
   assert(m->n_label >= 1);
   assert(m->n_label <= 3);
 
-#define LABEL_BUFFER_SIZE (2 * DATA_MAX_NAME_LEN + 4)
+#define LABEL_KEY_SIZE DATA_MAX_NAME_LEN
+#define LABEL_VALUE_SIZE (2 * DATA_MAX_NAME_LEN - 1)
+#define LABEL_BUFFER_SIZE (LABEL_KEY_SIZE + LABEL_VALUE_SIZE + 4)
 
   char *labels[3] = {
       (char[LABEL_BUFFER_SIZE]){0}, (char[LABEL_BUFFER_SIZE]){0},
       (char[LABEL_BUFFER_SIZE]){0},
   };
 
-  for (size_t i = 0; i < m->n_label; i++)
-    ssnprintf(labels[i], LABEL_BUFFER_SIZE, "%s=\"%s\"", m->label[i]->name,
-              m->label[i]->value);
+  /* N.B.: the label *names* are hard-coded by this plugin and therefore we
+   * know that they are sane. */
+  for (size_t i = 0; i < m->n_label; i++) {
+    char value[LABEL_VALUE_SIZE];
+    snprintf(labels[i], LABEL_BUFFER_SIZE, "%s=\"%s\"", m->label[i]->name,
+             escape_label_value(value, sizeof(value), m->label[i]->value));
+  }
 
   strjoin(buffer, buffer_size, labels, m->n_label, ",");
   return buffer;
@@ -135,13 +178,13 @@ static void format_text(ProtobufCBuffer *buffer) {
   while (c_avl_iterator_next(iter, (void *)&unused_name, (void *)&fam) == 0) {
     char line[1024]; /* 4x DATA_MAX_NAME_LEN? */
 
-    ssnprintf(line, sizeof(line), "# HELP %s %s\n", fam->name, fam->help);
+    snprintf(line, sizeof(line), "# HELP %s %s\n", fam->name, fam->help);
     buffer->append(buffer, strlen(line), (uint8_t *)line);
 
-    ssnprintf(line, sizeof(line), "# TYPE %s %s\n", fam->name,
-              (fam->type == IO__PROMETHEUS__CLIENT__METRIC_TYPE__GAUGE)
-                  ? "gauge"
-                  : "counter");
+    snprintf(line, sizeof(line), "# TYPE %s %s\n", fam->name,
+             (fam->type == IO__PROMETHEUS__CLIENT__METRIC_TYPE__GAUGE)
+                 ? "gauge"
+                 : "counter");
     buffer->append(buffer, strlen(line), (uint8_t *)line);
 
     for (size_t i = 0; i < fam->n_metric; i++) {
@@ -151,17 +194,17 @@ static void format_text(ProtobufCBuffer *buffer) {
 
       char timestamp_ms[24] = "";
       if (m->has_timestamp_ms)
-        ssnprintf(timestamp_ms, sizeof(timestamp_ms), " %" PRIi64,
-                  m->timestamp_ms);
+        snprintf(timestamp_ms, sizeof(timestamp_ms), " %" PRIi64,
+                 m->timestamp_ms);
 
       if (fam->type == IO__PROMETHEUS__CLIENT__METRIC_TYPE__GAUGE)
-        ssnprintf(line, sizeof(line), "%s{%s} " GAUGE_FORMAT "%s\n", fam->name,
-                  format_labels(labels, sizeof(labels), m), m->gauge->value,
-                  timestamp_ms);
+        snprintf(line, sizeof(line), "%s{%s} " GAUGE_FORMAT "%s\n", fam->name,
+                 format_labels(labels, sizeof(labels), m), m->gauge->value,
+                 timestamp_ms);
       else /* if (fam->type == IO__PROMETHEUS__CLIENT__METRIC_TYPE__COUNTER) */
-        ssnprintf(line, sizeof(line), "%s{%s} %.0f%s\n", fam->name,
-                  format_labels(labels, sizeof(labels), m), m->counter->value,
-                  timestamp_ms);
+        snprintf(line, sizeof(line), "%s{%s} %.0f%s\n", fam->name,
+                 format_labels(labels, sizeof(labels), m), m->counter->value,
+                 timestamp_ms);
 
       buffer->append(buffer, strlen(line), (uint8_t *)line);
     }
@@ -169,8 +212,8 @@ static void format_text(ProtobufCBuffer *buffer) {
   c_avl_iterator_destroy(iter);
 
   char server[1024];
-  ssnprintf(server, sizeof(server), "\n# collectd/write_prometheus %s at %s\n",
-            PACKAGE_VERSION, hostname_g);
+  snprintf(server, sizeof(server), "\n# collectd/write_prometheus %s at %s\n",
+           PACKAGE_VERSION, hostname_g);
   buffer->append(buffer, strlen(server), (uint8_t *)server);
 
   pthread_mutex_unlock(&metrics_lock);
@@ -210,12 +253,11 @@ static int http_handler(void *cls, struct MHD_Connection *connection,
   else
     format_text(buffer);
 
-  struct MHD_Response *res =
 #if defined(MHD_VERSION) && MHD_VERSION >= 0x00090500
-    MHD_create_response_from_buffer(
+  struct MHD_Response *res = MHD_create_response_from_buffer(
       simple.len, simple.data, MHD_RESPMEM_MUST_COPY);
 #else
-    MHD_create_response_from_data(
+  struct MHD_Response *res = MHD_create_response_from_data(
       simple.len, simple.data, /* must_free = */ 0, /* must_copy = */ 1);
 #endif
   MHD_add_response_header(res, MHD_HTTP_HEADER_CONTENT_TYPE,
@@ -504,9 +546,14 @@ metric_family_delete_metric(Io__Prometheus__Client__MetricFamily *fam,
             ((fam->n_metric - 1) - i) * sizeof(fam->metric[i]));
   fam->n_metric--;
 
+  if (fam->n_metric == 0) {
+    sfree(fam->metric);
+    return 0;
+  }
+
   Io__Prometheus__Client__Metric **tmp =
       realloc(fam->metric, fam->n_metric * sizeof(*fam->metric));
-  if ((tmp != NULL) || (fam->n_metric == 0))
+  if (tmp != NULL)
     fam->metric = tmp;
 
   return 0;
@@ -584,7 +631,7 @@ metric_family_create(char *name, data_set_t const *ds, value_list_t const *vl,
   msg->name = name;
 
   char help[1024];
-  ssnprintf(
+  snprintf(
       help, sizeof(help),
       "write_prometheus plugin: '%s' Type: '%s', Dstype: '%s', Dsname: '%s'",
       vl->plugin, vl->type, DS_TYPE_TO_STRING(ds->ds[ds_index].type),
@@ -652,8 +699,10 @@ metric_family_get(data_set_t const *ds, value_list_t const *vl, size_t ds_index,
     return fam;
   }
 
-  if (!allocate)
+  if (!allocate) {
+    sfree(name);
     return NULL;
+  }
 
   fam = metric_family_create(name, ds, vl, ds_index);
   if (fam == NULL) {
@@ -826,5 +875,3 @@ void module_register() {
                           /* user data = */ NULL);
   plugin_register_shutdown("write_prometheus", prom_shutdown);
 }
-
-/* vim: set sw=2 sts=2 et fdm=marker : */