Better memory management in chained list

key is now managed internally, using a copy.
add_elt() / add_key() now provide a 'suffix' parameter.
If suffix is given, it is appended to the key.
If NULL, or empty string ("") is given, nothing is appended.

NOTE : value is still owned by json object.

Bug-AGL: SPEC-2416

Change-Id: I624a2dd211801c2d24b2c6739f2c7536a047ea32
Signed-off-by: Johann CAHIER <johann.cahier@iot.bzh>

5 files changed, 47 insertions, 43 deletions

diff --git a/src/plugins/influxdb-reader.c b/src/plugins/influxdb-reader.c
index d7ddac7..c633e9f 100644
--- a/src/plugins/influxdb-reader.c
+++ b/src/plugins/influxdb-reader.c
@@ -70,10 +70,10 @@ static void fill_key(void *c, json_object *columnJ)
 	struct metrics_list *m_list = (struct metrics_list *)c;
 
 	if(strncasecmp(&column[length-2], "_t", 2) == 0) {
-		add_key(&m_list->serie.serie_columns.tags, column);
+		add_key(&m_list->serie.serie_columns.tags, column, "");
 	}
 	else if(strncasecmp(&column[length-2], "_f", 2) == 0) {
-		add_key(&m_list->serie.serie_columns.fields, column);
+		add_key(&m_list->serie.serie_columns.fields, column, "");
 	}
 }
 
diff --git a/src/plugins/influxdb-writer.c b/src/plugins/influxdb-writer.c
index 2815b19..a7ce8fc 100644
--- a/src/plugins/influxdb-writer.c
+++ b/src/plugins/influxdb-writer.c
@@ -136,7 +136,7 @@ CURL *make_curl_write_post(afb_api_t apiHandle, const char *url, json_object *me
 		   curl_wrap_prepare_post_unescaped(url, NULL, "\n", (const char * const*)post_data) : NULL;
 	free(serie);
 	for(i = 0; i < lpd; i++)
-		free(post_data[i]);
+		if (post_data[i]) free(post_data[i]);
 	free(post_data);
 
 	return curl;
@@ -155,6 +155,7 @@ CTLP_CAPI(write_to_influxdb, source, argsJ, eventJ)
 	const char *port = NULL;
 	const char *host = NULL;
 	CURL *curl_request;
+	int rc = -1;
 
 	json_object *req_args = afb_req_json(request),
 				*portJ = NULL,
@@ -163,15 +164,17 @@ CTLP_CAPI(write_to_influxdb, source, argsJ, eventJ)
 	if(wrap_json_unpack(req_args, "{s?s,s?o,so!}",
 			"host", &host,
 			"port", &portJ,
-			"metric", &metric) || ! metric)
+			"metric", &metric) || ! metric) {
 		afb_req_fail(request, "Failed", "Error processing arguments. Miss metric\
 JSON object or malformed");
-	else
+		rc = -1;
+	} else {
 		port = json_object_is_type(portJ, json_type_null) ?
 			NULL : json_object_to_json_string(portJ);
+		curl_request = influxdb_write(source->api, host, port, metric);
+		curl_wrap_do(curl_request, influxdb_write_curl_cb, request);
+		rc = 0;
+	}
 
-	curl_request = influxdb_write(source->api, host, port, metric);
-	curl_wrap_do(curl_request, influxdb_write_curl_cb, request);
-
-	return 0;
+	return rc;
 }
diff --git a/src/plugins/influxdb.c b/src/plugins/influxdb.c
index 2cfd551..b8f85d2 100644
--- a/src/plugins/influxdb.c
+++ b/src/plugins/influxdb.c
@@ -117,28 +117,12 @@ int create_database(afb_req_t request)
 
 void unpack_values(void* l, json_object* valuesJ, const char* key)
 {
-    struct list** oneList = (struct list**)l;
-
-    /* Append a suffix to be able to differentiate tags and fields at reading
-	   time */
-    char* suffixed_key = calloc(1, strlen(key) + 3);
-    strcpy(suffixed_key, key);
-    // strcat(suffixed_key, "_f");
-
-    add_elt(oneList, suffixed_key, valuesJ);
+    add_elt((struct list**)l, key, "", valuesJ);
 }
 
 void unpack_metadata(void* l, json_object* valuesJ, const char* key)
 {
-    struct list** oneList = (struct list**)l;
-
-    /* Append a suffix to be able to differentiate tags and fields at reading
-	   time */
-    char* suffixed_key = calloc(1, strlen(key) + 3);
-    strcpy(suffixed_key, key);
-    // strcat(suffixed_key, "_t");
-
-    add_elt(oneList, suffixed_key, valuesJ);
+    add_elt((struct list**)l, key, "", valuesJ);
 }
 
 void unpacking_from_api(void* s, json_object* valueJ, const char* key)
@@ -156,13 +140,13 @@ void unpacking_from_api(void* s, json_object* valueJ, const char* key)
     else if (strcasecmp("value", key) == 0 || strcasecmp("values", key) == 0)
         wrap_json_object_for_all(valueJ, unpack_values, (void*)&serie->serie_columns.fields);
     /* Treat all key looking for tag and field object. Those ones could be find
-	   with the last 2 character. '_t' for tag and '_f' that are the keys that
-	   could be indefinite. Cf influxdb documentation:
-	   https://docs.influxdata.com/influxdb/v1.5/write_protocols/line_protocol_reference/ */
+       with the last 2 character. '_t' for tag and '_f' that are the keys that
+       could be indefinite. Cf influxdb documentation:
+       https://docs.influxdata.com/influxdb/v1.5/write_protocols/line_protocol_reference/ */
     else if (strncasecmp(&key[key_length - 2], "_t", 2) == 0)
-        add_elt(&serie->serie_columns.tags, key, valueJ);
+        add_elt(&serie->serie_columns.tags, key, "", valueJ);
     else if (strncasecmp(&key[key_length - 2], "_f", 2) == 0)
-        add_elt(&serie->serie_columns.fields, key, valueJ);
+        add_elt(&serie->serie_columns.fields, key, "", valueJ);
 }
 
 int unpack_metric_from_api(json_object* m, struct series_t* serie)
diff --git a/src/utils/list.c b/src/utils/list.c
index c5152a3..030c759 100644
--- a/src/utils/list.c
+++ b/src/utils/list.c
@@ -25,14 +25,31 @@ void destroy_list(struct list* l)
     struct list* save;
     while (l != NULL) {
         save = l->next;
+        free(l->key);
         free(l);
         l = save;
     }
 }
 
-void add_elt(struct list** l, const char* key, json_object* value)
+void add_elt(struct list** l, const char* key, const char* suffix, json_object* value)
 {
-    struct list* new_elt;
+    struct list* new_elt = NULL;
+    char *suffixed_key = NULL;
+    size_t key_len = strlen(key), suffix_len = -1;
+
+    if (suffix == NULL) {
+        suffix = "";
+        suffix_len=0;
+    } else {
+        suffix_len = strlen(suffix);
+    }
+    suffixed_key = malloc(key_len + suffix_len + 1);
+    if (!suffixed_key) {
+        fprintf(stderr, "list.c, add_elt() : can't allocate 'suffixed_key' (out of memory)");
+        exit(1);
+    }
+    strncpy(suffixed_key, key, key_len);
+    strncpy(suffixed_key+key_len, suffix, suffix_len+1);
 
     // search tail
     new_elt = *l;
@@ -44,19 +61,19 @@ void add_elt(struct list** l, const char* key, json_object* value)
     // alloc new elem
     new_elt = malloc(sizeof(struct list));
     if (!new_elt) {
-        fprintf(stderr, "OUT of memory");
+        fprintf(stderr, "list.c, add_elt() : can't allocate 'new_elt' (out of memory)");
         exit(1);
     }
 
     *l = new_elt;
-    new_elt->key = key;
+    new_elt->key = suffixed_key;
     new_elt->value = value;
     new_elt->next = NULL;
 }
 
-void add_key(struct list** l, const char* key)
+void add_key(struct list** l, const char* key, const char* suffix)
 {
-    add_elt(l, key, NULL);
+    add_elt(l, key, suffix, NULL);
 }
 
 int set_value(struct list* l, json_object* val, int index)
diff --git a/src/utils/list.h b/src/utils/list.h
index 9f93cb6..c0d559f 100644
--- a/src/utils/list.h
+++ b/src/utils/list.h
@@ -21,17 +21,17 @@
 #include <json-c/json.h>
 
 struct list {
-	const char *key;
+	char *key;
 	json_object *value;
 	struct list *next;
 };
 
 void destroy_list(struct list *l);
-void add_elt(struct list **l, const char *key, json_object *value);
-void add_key(struct list **l, const char *key);
+void add_elt(struct list **l, const char *key, const char* suffix, json_object *value);
+void add_key(struct list **l, const char *key, const char* suffix);
 int set_value(struct list *l, json_object *val, int index);
 struct list *get_elt(struct list *l, int index);
-struct list *find_elt_from_key(struct list *l, const char *key);
-json_object *find_key_value(struct list *l, const char *key);
+struct list *find_elt_from_key(struct list *l, const char *suffixed_key);
+json_object *find_key_value(struct list *l, const char *suffixed_key);
 
 #endif