Escaped special characters for measurement, tags and fields

See https://docs.influxdata.com/influxdb/v1.5/write_protocols/line_protocol_reference/#special-characters
for more info.

Change-Id: Iad2f7d00b7d6c42dbea33df03a75353e9cac97a9
Signed-off-by: Sebastien Douheret <sebastien.douheret@iot.bzh>

3 files changed, 68 insertions, 14 deletions

diff --git a/.vscode/settings.json b/.vscode/settings.json
index c3366cb..8337700 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -21,7 +21,8 @@
         "type_traits": "c",
         "influxdb.h": "c",
         "tsdb.h": "c",
-        "ctl-plugin.h": "c"
+        "ctl-plugin.h": "c",
+        "escape.h": "c"
     },
 	"C_Cpp.intelliSenseEngineFallback": "Disabled",
     "C_Cpp.errorSquiggles": "Disabled",
diff --git a/src/plugins/influxdb-writer.c b/src/plugins/influxdb-writer.c
index aaa8991..be02e34 100644
--- a/src/plugins/influxdb-writer.c
+++ b/src/plugins/influxdb-writer.c
@@ -56,7 +56,7 @@ static size_t format_write_args(char *query, struct series_t *serie)
 	struct list *tags = serie->serie_columns.tags;
 	struct list *fields = serie->serie_columns.fields;
 
-	strncat(query, serie->name, strlen(serie->name));
+    concatenate(query, serie->name, NULL);
 	if(tags) {
 		while(tags != NULL) {
 			concatenate(query, tags->key, ",");
@@ -132,6 +132,8 @@ CURL *make_curl_write_post(AFB_ApiT apiHandle, const char *url, json_object *met
 		}
 	}
 
+    AFB_ApiDebug(apiHandle, "influx curl: url=%s data=%s", url, (const char*) *post_data);
+
 	/* Check that we just do not broke the for loop before trying preparing CURL
 	   request object */
 	curl = i == lpd ?
diff --git a/src/plugins/influxdb.h b/src/plugins/influxdb.h
index 0f06dda..88ea2bc 100644
--- a/src/plugins/influxdb.h
+++ b/src/plugins/influxdb.h
@@ -21,32 +21,83 @@
 #define _GNU_SOURCE
 #include <string.h>
 
+#include "../utils/list.h"
 #include "ctl-plugin.h"
-#include "wrap-json.h"
 #include "tsdb.h"
-#include "../utils/list.h"
+#include "wrap-json.h"
 
 struct serie_columns_t {
-	struct list *tags;
-	struct list *fields;
+    struct list* tags;
+    struct list* fields;
 };
 
 struct series_t {
-	const char *name;
-	struct serie_columns_t serie_columns;
-	uint64_t timestamp;
+    const char* name;
+    struct serie_columns_t serie_columns;
+    uint64_t timestamp;
 };
 
 int create_database(AFB_ReqT request);
 
-int unpack_metric_from_api(json_object *m, struct series_t *serie);
+int unpack_metric_from_api(json_object* m, struct series_t* serie);
+
+static inline int should_escape(char c)
+{
+    switch (c) {
+    case ',':
+    case '=':
+    case ' ':
+    case '"':
+        return 1;
+        break;
+    }
+    return 0;
+}
+
+static inline char* escape_chr(const char* src)
+{
+    int j, i = 0;
+    size_t len, src_len;
+    char* res;
+
+    len = src_len = strlen(src);
+    while (i < src_len) {
+        if (should_escape(src[i++]))
+            len++;
+    }
+
+    if (len == src_len) {
+        res = strdup(src);
+    } else {
+        res = malloc(len + 1);
+        if (res) {
+            i = j = 0;
+            while (i < src_len) {
+                if (should_escape(src[i]))
+                    res[j++] = '\\';
+                res[j++] = src[i++];
+            }
+        }
+        res[j] = '\0';
+    }
+    return res;
+}
 
-static inline void concatenate(char* dest, const char* source, const char *sep)
+static inline void concatenate(char* dest, const char* source, const char* sep)
 {
-	strncat(dest, sep, strlen(sep));
-	strncat(dest, source, strlen(source));
+    char* esc_source;
+
+    if (sep)
+        strncat(dest, sep, strlen(sep));
+
+    esc_source = escape_chr(source);
+
+    strncat(dest, esc_source, strlen(esc_source));
+
+    if (esc_source)
+        free(esc_source);
 }
 
-size_t make_url(char *url, size_t l_url, const char *host, const char *port, const char *endpoint);
+size_t make_url(char* url, size_t l_url, const char* host, const char* port, const char* endpoint);
 
 #endif