X-Git-Url: https://git.octo.it/?p=collectd.git;a=blobdiff_plain;f=src%2Fcurl_json.c;h=f0badc998e05c2be1f45e0f04bcc365f88d3ab56;hp=9ec9f1e260d341a6088aa8d339ded7463ded7c2c;hb=06a86a60a7dabc685bdbd81ce3d36ea5f7e2c2d4;hpb=307c875e5a78a2729fbbe1a588d232e9a129d75a

diff --git a/src/curl_json.c b/src/curl_json.c
index 9ec9f1e2..f0badc99 100644
--- a/src/curl_json.c
+++ b/src/curl_json.c
@@ -44,8 +44,6 @@
 #endif
 
 #define CJ_DEFAULT_HOST "localhost"
-#define CJ_KEY_MAGIC 0x43484b59UL /* CHKY */
-#define CJ_IS_KEY(key) ((key)->magic == CJ_KEY_MAGIC)
 #define CJ_ANY "*"
 #define COUCH_MIN(x, y) ((x) < (y) ? (x) : (y))
 
@@ -53,16 +51,38 @@ struct cj_key_s;
 typedef struct cj_key_s cj_key_t;
 struct cj_key_s /* {{{ */
 {
-  unsigned long magic;
   char *path;
   char *type;
   char *instance;
 };
 /* }}} */
 
+/* cj_tree_entry_t is a union of either a metric configuration ("key") or a tree
+ * mapping array indexes / map keys to a descendant cj_tree_entry_t*. */
+typedef struct {
+  enum { KEY, TREE } type;
+  union {
+    c_avl_tree_t *tree;
+    cj_key_t *key;
+  };
+} cj_tree_entry_t;
+
+/* cj_state_t is a stack providing the configuration relevant for the context
+ * that is currently being parsed. If entry->type == KEY, the parser should
+ * expect a metric (a numeric value). If entry->type == TREE, the parser should
+ * expect an array of map to descent into. If entry == NULL, no configuration
+ * exists for this part of the JSON structure. */
+typedef struct {
+  cj_tree_entry_t *entry;
+  bool in_array;
+  int index;
+  char name[DATA_MAX_NAME_LEN];
+} cj_state_t;
+
 struct cj_s /* {{{ */
 {
   char *instance;
+  char *plugin_name;
   char *host;
 
   char *sock;
@@ -71,9 +91,9 @@ struct cj_s /* {{{ */
   char *user;
   char *pass;
   char *credentials;
-  _Bool digest;
-  _Bool verify_peer;
-  _Bool verify_host;
+  bool digest;
+  bool verify_peer;
+  bool verify_host;
   char *cacert;
   struct curl_slist *headers;
   char *post_body;
@@ -86,17 +106,8 @@ struct cj_s /* {{{ */
 
   yajl_handle yajl;
   c_avl_tree_t *tree;
-  cj_key_t *key;
   int depth;
-  struct {
-    union {
-      c_avl_tree_t *tree;
-      cj_key_t *key;
-    };
-    _Bool in_array;
-    int index;
-    char name[DATA_MAX_NAME_LEN];
-  } state[YAJL_MAX_DEPTH];
+  cj_state_t state[YAJL_MAX_DEPTH];
 };
 typedef struct cj_s cj_t; /* }}} */
 
@@ -107,7 +118,11 @@ typedef unsigned int yajl_len_t;
 #endif
 
 static int cj_read(user_data_t *ud);
-static void cj_submit(cj_t *db, cj_key_t *key, value_t *value);
+static void cj_submit_impl(cj_t *db, cj_key_t *key, value_t *value);
+
+/* cj_submit is a function pointer to cj_submit_impl, allowing the unit-test to
+ * overwrite which function is called. */
+static void (*cj_submit)(cj_t *, cj_key_t *, value_t *) = cj_submit_impl;
 
 static size_t cj_curl_callback(void *buf, /* {{{ */
                                size_t size, size_t nmemb, void *user_data) {
@@ -141,12 +156,10 @@ static size_t cj_curl_callback(void *buf, /* {{{ */
 } /* }}} size_t cj_curl_callback */
 
 static int cj_get_type(cj_key_t *key) {
-  const data_set_t *ds;
-
-  if ((key == NULL) || !CJ_IS_KEY(key))
+  if (key == NULL)
     return -EINVAL;
 
-  ds = plugin_get_ds(key->type);
+  const data_set_t *ds = plugin_get_ds(key->type);
   if (ds == NULL) {
     static char type[DATA_MAX_NAME_LEN] = "!!!invalid!!!";
 
@@ -171,78 +184,85 @@ static int cj_get_type(cj_key_t *key) {
   return ds->ds[0].type;
 }
 
-static int cj_cb_map_key(void *ctx, const unsigned char *val, yajl_len_t len);
+/* cj_load_key loads the configuration for "key" from the parent context and
+ * sets either .key or .tree in the current context. */
+static int cj_load_key(cj_t *db, char const *key) {
+  if (db == NULL || key == NULL || db->depth <= 0)
+    return EINVAL;
 
-static void cj_cb_inc_array_index(void *ctx, _Bool update_key) {
-  cj_t *db = (cj_t *)ctx;
+  sstrncpy(db->state[db->depth].name, key, sizeof(db->state[db->depth].name));
+
+  if (db->state[db->depth - 1].entry == NULL ||
+      db->state[db->depth - 1].entry->type != TREE) {
+    return 0;
+  }
+
+  c_avl_tree_t *tree = db->state[db->depth - 1].entry->tree;
+  cj_tree_entry_t *e = NULL;
+
+  if (c_avl_get(tree, key, (void *)&e) == 0) {
+    db->state[db->depth].entry = e;
+  } else if (c_avl_get(tree, CJ_ANY, (void *)&e) == 0) {
+    db->state[db->depth].entry = e;
+  } else {
+    db->state[db->depth].entry = NULL;
+  }
+
+  return 0;
+}
 
+static void cj_advance_array(cj_t *db) {
   if (!db->state[db->depth].in_array)
     return;
 
   db->state[db->depth].index++;
 
-  if (update_key) {
-    char name[DATA_MAX_NAME_LEN];
-
-    ssnprintf(name, sizeof(name), "%d", db->state[db->depth].index - 1);
-
-    cj_cb_map_key(ctx, (unsigned char *)name, (yajl_len_t)strlen(name));
-  }
+  char name[DATA_MAX_NAME_LEN];
+  snprintf(name, sizeof(name), "%d", db->state[db->depth].index);
+  cj_load_key(db, name);
 }
 
 /* yajl callbacks */
 #define CJ_CB_ABORT 0
 #define CJ_CB_CONTINUE 1
 
-static int cj_cb_boolean(void *ctx, int boolVal) {
-  cj_cb_inc_array_index(ctx, /* update_key = */ 0);
-  return CJ_CB_CONTINUE;
-}
-
 static int cj_cb_null(void *ctx) {
-  cj_cb_inc_array_index(ctx, /* update_key = */ 0);
+  cj_advance_array(ctx);
   return CJ_CB_CONTINUE;
 }
 
 static int cj_cb_number(void *ctx, const char *number, yajl_len_t number_len) {
-  char buffer[number_len + 1];
-
   cj_t *db = (cj_t *)ctx;
-  cj_key_t *key = db->state[db->depth].key;
-  value_t vt;
-  int type;
-  int status;
 
   /* Create a null-terminated version of the string. */
+  char buffer[number_len + 1];
   memcpy(buffer, number, number_len);
   buffer[sizeof(buffer) - 1] = 0;
 
-  if ((key == NULL) || !CJ_IS_KEY(key)) {
-    if (key != NULL &&
-        !db->state[db->depth].in_array /*can be inhomogeneous*/) {
-      NOTICE("curl_json plugin: Found \"%s\", but the configuration expects"
-             " a map.",
+  if (db->state[db->depth].entry == NULL ||
+      db->state[db->depth].entry->type != KEY) {
+    if (db->state[db->depth].entry != NULL) {
+      NOTICE("curl_json plugin: Found \"%s\", but the configuration expects a "
+             "map.",
              buffer);
-      return CJ_CB_CONTINUE;
-    }
-
-    cj_cb_inc_array_index(ctx, /* update_key = */ 1);
-    key = db->state[db->depth].key;
-    if ((key == NULL) || !CJ_IS_KEY(key)) {
-      return CJ_CB_CONTINUE;
     }
-  } else {
-    cj_cb_inc_array_index(ctx, /* update_key = */ 1);
+    cj_advance_array(ctx);
+    return CJ_CB_CONTINUE;
   }
 
-  type = cj_get_type(key);
-  status = parse_value(buffer, &vt, type);
+  cj_key_t *key = db->state[db->depth].entry->key;
+
+  int type = cj_get_type(key);
+  value_t vt;
+  int status = parse_value(buffer, &vt, type);
   if (status != 0) {
     NOTICE("curl_json plugin: Unable to parse number: \"%s\"", buffer);
+    cj_advance_array(ctx);
     return CJ_CB_CONTINUE;
   }
 
   cj_submit(db, key, &vt);
+  cj_advance_array(ctx);
   return CJ_CB_CONTINUE;
 } /* int cj_cb_number */
 
@@ -251,38 +271,13 @@ static int cj_cb_number(void *ctx, const char *number, yajl_len_t number_len) {
  * NULL. */
 static int cj_cb_map_key(void *ctx, unsigned char const *in_name,
                          yajl_len_t in_name_len) {
-  cj_t *db = (cj_t *)ctx;
-  c_avl_tree_t *tree;
+  char name[in_name_len + 1];
 
-  tree = db->state[db->depth - 1].tree;
-
-  if (tree != NULL) {
-    cj_key_t *value = NULL;
-    char *name;
-    size_t name_len;
-
-    /* Create a null-terminated version of the name. */
-    name = db->state[db->depth].name;
-    name_len =
-        COUCH_MIN((size_t)in_name_len, sizeof(db->state[db->depth].name) - 1);
-    memcpy(name, in_name, name_len);
-    name[name_len] = 0;
-
-    if (c_avl_get(tree, name, (void *)&value) == 0) {
-      if (CJ_IS_KEY((cj_key_t *)value)) {
-        db->state[db->depth].key = value;
-      } else {
-        db->state[db->depth].tree = (c_avl_tree_t *)value;
-      }
-    } else if (c_avl_get(tree, CJ_ANY, (void *)&value) == 0)
-      if (CJ_IS_KEY((cj_key_t *)value)) {
-        db->state[db->depth].key = value;
-      } else {
-        db->state[db->depth].tree = (c_avl_tree_t *)value;
-      }
-    else
-      db->state[db->depth].key = NULL;
-  }
+  memmove(name, in_name, in_name_len);
+  name[sizeof(name) - 1] = 0;
+
+  if (cj_load_key(ctx, name) != 0)
+    return CJ_CB_ABORT;
 
   return CJ_CB_CONTINUE;
 }
@@ -292,43 +287,55 @@ static int cj_cb_string(void *ctx, const unsigned char *val, yajl_len_t len) {
   return cj_cb_number(ctx, (const char *)val, len);
 } /* int cj_cb_string */
 
-static int cj_cb_start(void *ctx) {
-  cj_t *db = (cj_t *)ctx;
-  if (++db->depth >= YAJL_MAX_DEPTH) {
-    ERROR("curl_json plugin: %s depth exceeds max, aborting.",
-          db->url ? db->url : db->sock);
-    return CJ_CB_ABORT;
-  }
-  return CJ_CB_CONTINUE;
-}
+static int cj_cb_boolean(void *ctx, int boolVal) {
+  if (boolVal)
+    return cj_cb_number(ctx, "1", 1);
+  else
+    return cj_cb_number(ctx, "0", 1);
+} /* int cj_cb_boolean */
 
 static int cj_cb_end(void *ctx) {
   cj_t *db = (cj_t *)ctx;
-  db->state[db->depth].tree = NULL;
-  --db->depth;
+  memset(&db->state[db->depth], 0, sizeof(db->state[db->depth]));
+  db->depth--;
+  cj_advance_array(ctx);
   return CJ_CB_CONTINUE;
 }
 
 static int cj_cb_start_map(void *ctx) {
-  cj_cb_inc_array_index(ctx, /* update_key = */ 1);
-  return cj_cb_start(ctx);
+  cj_t *db = (cj_t *)ctx;
+
+  if ((db->depth + 1) >= YAJL_MAX_DEPTH) {
+    ERROR("curl_json plugin: %s depth exceeds max, aborting.",
+          db->url ? db->url : db->sock);
+    return CJ_CB_ABORT;
+  }
+  db->depth++;
+  return CJ_CB_CONTINUE;
 }
 
 static int cj_cb_end_map(void *ctx) { return cj_cb_end(ctx); }
 
 static int cj_cb_start_array(void *ctx) {
   cj_t *db = (cj_t *)ctx;
-  cj_cb_inc_array_index(ctx, /* update_key = */ 1);
-  if (db->depth + 1 < YAJL_MAX_DEPTH) {
-    db->state[db->depth + 1].in_array = 1;
-    db->state[db->depth + 1].index = 0;
+
+  if ((db->depth + 1) >= YAJL_MAX_DEPTH) {
+    ERROR("curl_json plugin: %s depth exceeds max, aborting.",
+          db->url ? db->url : db->sock);
+    return CJ_CB_ABORT;
   }
-  return cj_cb_start(ctx);
+  db->depth++;
+  db->state[db->depth].in_array = true;
+  db->state[db->depth].index = 0;
+
+  cj_load_key(db, "0");
+
+  return CJ_CB_CONTINUE;
 }
 
 static int cj_cb_end_array(void *ctx) {
   cj_t *db = (cj_t *)ctx;
-  db->state[db->depth].in_array = 0;
+  db->state[db->depth].in_array = false;
   return cj_cb_end(ctx);
 }
 
@@ -357,17 +364,16 @@ static void cj_key_free(cj_key_t *key) /* {{{ */
 static void cj_tree_free(c_avl_tree_t *tree) /* {{{ */
 {
   char *name;
-  void *value;
+  cj_tree_entry_t *e;
 
-  while (c_avl_pick(tree, (void *)&name, (void *)&value) == 0) {
-    cj_key_t *key = (cj_key_t *)value;
+  while (c_avl_pick(tree, (void *)&name, (void *)&e) == 0) {
+    sfree(name);
 
-    if (CJ_IS_KEY(key))
-      cj_key_free(key);
+    if (e->type == KEY)
+      cj_key_free(e->key);
     else
-      cj_tree_free((c_avl_tree_t *)value);
-
-    sfree(name);
+      cj_tree_free(e->tree);
+    sfree(e);
   }
 
   c_avl_destroy(tree);
@@ -393,6 +399,7 @@ static void cj_free(void *arg) /* {{{ */
   db->tree = NULL;
 
   sfree(db->instance);
+  sfree(db->plugin_name);
   sfree(db->host);
 
   sfree(db->sock);
@@ -412,7 +419,7 @@ static void cj_free(void *arg) /* {{{ */
 /* Configuration handling functions {{{ */
 
 static c_avl_tree_t *cj_avl_create(void) {
-  return c_avl_create((int(*)(const void *, const void *))strcmp);
+  return c_avl_create((int (*)(const void *, const void *))strcmp);
 }
 
 static int cj_config_append_string(const char *name,
@@ -433,6 +440,67 @@ static int cj_config_append_string(const char *name,
   return 0;
 } /* }}} int cj_config_append_string */
 
+/* cj_append_key adds key to the configuration stored in db.
+ *
+ * For example:
+ * "httpd/requests/count",
+ * "httpd/requests/current" ->
+ * { "httpd": { "requests": { "count": $key, "current": $key } } }
+ */
+static int cj_append_key(cj_t *db, cj_key_t *key) { /* {{{ */
+  if (db->tree == NULL)
+    db->tree = cj_avl_create();
+
+  c_avl_tree_t *tree = db->tree;
+
+  char const *start = key->path;
+  if (*start == '/')
+    ++start;
+
+  char const *end;
+  while ((end = strchr(start, '/')) != NULL) {
+    char name[PATH_MAX];
+
+    size_t len = end - start;
+    if (len == 0)
+      break;
+
+    len = COUCH_MIN(len, sizeof(name) - 1);
+    sstrncpy(name, start, len + 1);
+
+    cj_tree_entry_t *e;
+    if (c_avl_get(tree, name, (void *)&e) != 0) {
+      e = calloc(1, sizeof(*e));
+      if (e == NULL)
+        return ENOMEM;
+      e->type = TREE;
+      e->tree = cj_avl_create();
+
+      c_avl_insert(tree, strdup(name), e);
+    }
+
+    if (e->type != TREE)
+      return EINVAL;
+
+    tree = e->tree;
+    start = end + 1;
+  }
+
+  if (strlen(start) == 0) {
+    ERROR("curl_json plugin: invalid key: %s", key->path);
+    return -1;
+  }
+
+  cj_tree_entry_t *e = calloc(1, sizeof(*e));
+  if (e == NULL)
+    return ENOMEM;
+  e->type = KEY;
+  e->key = key;
+
+  c_avl_insert(tree, strdup(start), e);
+  return 0;
+} /* }}} int cj_append_key */
+
 static int cj_config_add_key(cj_t *db, /* {{{ */
                              oconfig_item_t *ci) {
   cj_key_t *key;
@@ -449,7 +517,6 @@ static int cj_config_add_key(cj_t *db, /* {{{ */
     ERROR("curl_json plugin: calloc failed.");
     return -1;
   }
-  key->magic = CJ_KEY_MAGIC;
 
   if (strcasecmp("Key", ci->key) == 0) {
     status = cf_util_get_string(ci, &key->path);
@@ -493,53 +560,13 @@ static int cj_config_add_key(cj_t *db, /* {{{ */
     return -1;
   }
 
-  /* store path in a tree that will match the json map structure, example:
-   * "httpd/requests/count",
-   * "httpd/requests/current" ->
-   * { "httpd": { "requests": { "count": $key, "current": $key } } }
-   */
-  char *ptr;
-  char *name;
-  c_avl_tree_t *tree;
-
-  if (db->tree == NULL)
-    db->tree = cj_avl_create();
-
-  tree = db->tree;
-  ptr = key->path;
-  if (*ptr == '/')
-    ++ptr;
-
-  name = ptr;
-  while ((ptr = strchr(name, '/')) != NULL) {
-    char ent[PATH_MAX];
-    c_avl_tree_t *value;
-    size_t len;
-
-    len = ptr - name;
-    if (len == 0)
-      break;
-
-    len = COUCH_MIN(len, sizeof(ent) - 1);
-    sstrncpy(ent, name, len + 1);
-
-    if (c_avl_get(tree, ent, (void *)&value) != 0) {
-      value = cj_avl_create();
-      c_avl_insert(tree, strdup(ent), value);
-    }
-
-    tree = value;
-    name = ptr + 1;
-  }
-
-  if (strlen(name) == 0) {
-    ERROR("curl_json plugin: invalid key: %s", key->path);
+  status = cj_append_key(db, key);
+  if (status != 0) {
     cj_key_free(key);
     return -1;
   }
 
-  c_avl_insert(tree, strdup(name), key);
-  return status;
+  return 0;
 } /* }}} int cj_config_add_key */
 
 static int cj_init_curl(cj_t *db) /* {{{ */
@@ -555,7 +582,6 @@ static int cj_init_curl(cj_t *db) /* {{{ */
   curl_easy_setopt(db->curl, CURLOPT_WRITEDATA, db);
   curl_easy_setopt(db->curl, CURLOPT_USERAGENT, COLLECTD_USERAGENT);
   curl_easy_setopt(db->curl, CURLOPT_ERRORBUFFER, db->curl_errbuf);
-  curl_easy_setopt(db->curl, CURLOPT_URL, db->url);
   curl_easy_setopt(db->curl, CURLOPT_FOLLOWLOCATION, 1L);
   curl_easy_setopt(db->curl, CURLOPT_MAXREDIRS, 50L);
 
@@ -577,8 +603,8 @@ static int cj_init_curl(cj_t *db) /* {{{ */
       return -1;
     }
 
-    ssnprintf(db->credentials, credentials_size, "%s:%s", db->user,
-              (db->pass == NULL) ? "" : db->pass);
+    snprintf(db->credentials, credentials_size, "%s:%s", db->user,
+             (db->pass == NULL) ? "" : db->pass);
     curl_easy_setopt(db->curl, CURLOPT_USERPWD, db->credentials);
 #endif
 
@@ -650,6 +676,8 @@ static int cj_config_add_url(oconfig_item_t *ci) /* {{{ */
 
     if (strcasecmp("Instance", child->key) == 0)
       status = cf_util_get_string(child, &db->instance);
+    else if (strcasecmp("Plugin", child->key) == 0)
+      status = cf_util_get_string(child, &db->plugin_name);
     else if (strcasecmp("Host", child->key) == 0)
       status = cf_util_get_string(child, &db->host);
     else if (db->url && strcasecmp("User", child->key) == 0)
@@ -767,7 +795,7 @@ static const char *cj_host(cj_t *db) /* {{{ */
   return db->host;
 } /* }}} cj_host */
 
-static void cj_submit(cj_t *db, cj_key_t *key, value_t *value) /* {{{ */
+static void cj_submit_impl(cj_t *db, cj_key_t *key, value_t *value) /* {{{ */
 {
   value_list_t vl = VALUE_LIST_INIT;
 
@@ -777,13 +805,14 @@ static void cj_submit(cj_t *db, cj_key_t *key, value_t *value) /* {{{ */
   if (key->instance == NULL) {
     int len = 0;
     for (int i = 0; i < db->depth; i++)
-      len += ssnprintf(vl.type_instance + len, sizeof(vl.type_instance) - len,
-                       i ? "-%s" : "%s", db->state[i + 1].name);
+      len += snprintf(vl.type_instance + len, sizeof(vl.type_instance) - len,
+                      i ? "-%s" : "%s", db->state[i + 1].name);
   } else
     sstrncpy(vl.type_instance, key->instance, sizeof(vl.type_instance));
 
   sstrncpy(vl.host, cj_host(db), sizeof(vl.host));
-  sstrncpy(vl.plugin, "curl_json", sizeof(vl.plugin));
+  sstrncpy(vl.plugin, (db->plugin_name != NULL) ? db->plugin_name : "curl_json",
+           sizeof(vl.plugin));
   sstrncpy(vl.plugin_instance, db->instance, sizeof(vl.plugin_instance));
   sstrncpy(vl.type, key->type, sizeof(vl.type));
 
@@ -791,13 +820,13 @@ static void cj_submit(cj_t *db, cj_key_t *key, value_t *value) /* {{{ */
     vl.interval = db->interval;
 
   plugin_dispatch_values(&vl);
-} /* }}} int cj_submit */
+} /* }}} int cj_submit_impl */
 
 static int cj_sock_perform(cj_t *db) /* {{{ */
 {
-  char errbuf[1024];
-  struct sockaddr_un sa_unix = {0};
-  sa_unix.sun_family = AF_UNIX;
+  struct sockaddr_un sa_unix = {
+      .sun_family = AF_UNIX,
+  };
   sstrncpy(sa_unix.sun_path, db->sock, sizeof(sa_unix.sun_path));
 
   int fd = socket(AF_UNIX, SOCK_STREAM, 0);
@@ -805,8 +834,7 @@ static int cj_sock_perform(cj_t *db) /* {{{ */
     return -1;
   if (connect(fd, (struct sockaddr *)&sa_unix, sizeof(sa_unix)) < 0) {
     ERROR("curl_json plugin: connect(%s) failed: %s",
-          (db->sock != NULL) ? db->sock : "<null>",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+          (db->sock != NULL) ? db->sock : "<null>", STRERRNO);
     close(fd);
     return -1;
   }
@@ -817,8 +845,7 @@ static int cj_sock_perform(cj_t *db) /* {{{ */
     red = read(fd, buffer, sizeof(buffer));
     if (red < 0) {
       ERROR("curl_json plugin: read(%s) failed: %s",
-            (db->sock != NULL) ? db->sock : "<null>",
-            sstrerror(errno, errbuf, sizeof(errbuf)));
+            (db->sock != NULL) ? db->sock : "<null>", STRERRNO);
       close(fd);
       return -1;
     }
@@ -834,12 +861,13 @@ static int cj_curl_perform(cj_t *db) /* {{{ */
   int status;
   long rc;
   char *url;
-  url = db->url;
+
+  curl_easy_setopt(db->curl, CURLOPT_URL, db->url);
 
   status = curl_easy_perform(db->curl);
   if (status != CURLE_OK) {
     ERROR("curl_json plugin: curl_easy_perform failed with status %i: %s (%s)",
-          status, db->curl_errbuf, url);
+          status, db->curl_errbuf, db->url);
     return -1;
   }
   if (db->stats != NULL)
@@ -922,10 +950,19 @@ static int cj_read(user_data_t *ud) /* {{{ */
 
   db->depth = 0;
   memset(&db->state, 0, sizeof(db->state));
-  db->state[db->depth].tree = db->tree;
-  db->key = NULL;
 
-  return cj_perform(db);
+  /* This is not a compound literal because EPEL6's GCC is not cool enough to
+   * handle anonymous unions within compound literals. */
+  cj_tree_entry_t root = {0};
+  root.type = TREE;
+  root.tree = db->tree;
+  db->state[0].entry = &root;
+
+  int status = cj_perform(db);
+
+  db->state[0].entry = NULL;
+
+  return status;
 } /* }}} int cj_read */
 
 static int cj_init(void) /* {{{ */