wsutil: rename some wsjson functions

Rename wsjson_unescape_json_string to json_decode_string_inplace
(inspired by the g_base64_decode_inplace name). Rename
wsjson_is_valid_json to json_validate (inspired by g_unichar_validate).

Ideally json_parse is inlined with its user (sharkd_session.c), but that
requires exporting the jsmn_init and jsmn_parse functions... Hence the
dependency on jsmn.h remains in wsjson.h.

Change-Id: I7ecfe3565f15516e9115cbd7e025362df2da5416
Reviewed-on: https://code.wireshark.org/review/30731
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot
Reviewed-by: Anders Broman <a.broman58@gmail.com>

debian/libwsutil0.symbols

@@ -100,6 +100,9 @@ libwsutil.so.0 libwsutil0 #MINVER#
  isdigit_string@Base 1.10.0
  isprint_string@Base 1.10.0
  isprint_utf8_string@Base 2.6.1
+ json_decode_string_inplace@Base 2.9.0
+ json_parse@Base 2.9.0
+ json_validate@Base 2.9.0
  linear2alaw@Base 1.12.0~rc1
  linear2ulaw@Base 1.12.0~rc1
  local_interfaces_to_list@Base 2.1.2
@@ -201,6 +204,3 @@ libwsutil.so.0 libwsutil0 #MINVER#
  ws_utf8_char_len@Base 1.12.0~rc1
  ws_vadd_crash_info@Base 2.5.2
  ws_xton@Base 1.12.0~rc1
- wsjson_parse@Base 2.9.0
- wsjson_unescape_json_string@Base 2.9.0
- wsjson_is_valid_json@Base 2.9.0

epan/dissectors/packet-json.c

@@ -755,7 +755,7 @@ dissect_json_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *dat
 	guint len = tvb_captured_length(tvb);
 	const guint8* buf = tvb_get_string_enc(wmem_packet_scope(), tvb, 0, len, ENC_ASCII);
 
-	if (wsjson_is_valid_json(buf, len) == FALSE)
+	if (json_validate(buf, len) == FALSE)
 		return FALSE;
 
 	return (dissect_json(tvb, pinfo, tree, data) != 0);

sharkd_session.c

@@ -79,12 +79,6 @@ struct sharkd_filter_item
 
 static GHashTable *filter_table = NULL;
 
-static gboolean
-json_unescape_str(char *input)
-{
-	return wsjson_unescape_json_string(input, input);
-}
-
 static const char *
 json_find_attr(const char *buf, const jsmntok_t *tokens, int count, const char *attr)
 {
@@ -4321,7 +4315,7 @@ sharkd_session_process(char *buf, const jsmntok_t *tokens, int count)
 		buf[tokens[i + 1].end] = '\0';
 
 		/* unescape only value, as keys are simple strings */
-		if (tokens[i + 1].type == JSMN_STRING && !json_unescape_str(&buf[tokens[i + 1].start]))
+		if (tokens[i + 1].type == JSMN_STRING && !json_decode_string_inplace(&buf[tokens[i + 1].start]))
 		{
 			fprintf(stderr, "sanity check(3b): [%d] cannot unescape string\n", i + 1);
 			return;
@@ -4416,7 +4410,7 @@ sharkd_session_main(void)
 		/* every command is line seperated JSON */
 		int ret;
 
-		ret = wsjson_parse(buf, NULL, 0);
+		ret = json_parse(buf, NULL, 0);
 		if (ret < 0)
 		{
 			fprintf(stderr, "invalid JSON -> closing\n");
@@ -4434,7 +4428,7 @@ sharkd_session_main(void)
 
 		memset(tokens, 0, ret * sizeof(jsmntok_t));
 
-		ret = wsjson_parse(buf, tokens, ret);
+		ret = json_parse(buf, tokens, ret);
 		if (ret < 0)
 		{
 			fprintf(stderr, "invalid JSON(2) -> closing\n");

wiretap/json.c

@@ -42,7 +42,7 @@ wtap_open_return_val json_open(wtap *wth, int *err, gchar **err_info)
         return WTAP_OPEN_NOT_MINE;
     }
 
-    if (wsjson_is_valid_json(filebuf, bytes_read) == FALSE) {
+    if (json_validate(filebuf, bytes_read) == FALSE) {
         g_free(filebuf);
         return WTAP_OPEN_NOT_MINE;
     }

wsutil/wsjson.c

@@ -1,5 +1,5 @@
 /* wsjson.c
- * Utility to check if a payload is json using other libraries.
+ * JSON parsing functions.
  *
  * Copyright 2016, Dario Lombardo
  *
@@ -24,7 +24,8 @@
 #include <json-glib/json-glib.h>
 #endif
 
-gboolean wsjson_is_valid_json(const guint8* buf, const size_t len)
+gboolean
+json_validate(const guint8 *buf, const size_t len)
 {
     gboolean ret = TRUE;
 #ifdef HAVE_JSONGLIB
@@ -69,7 +70,8 @@ gboolean wsjson_is_valid_json(const guint8* buf, const size_t len)
     return ret;
 }
 
-int wsjson_parse(const char *buf, jsmntok_t *tokens, unsigned int max_tokens)
+int
+json_parse(const char *buf, jsmntok_t *tokens, unsigned int max_tokens)
 {
     jsmn_parser p;
 
@@ -77,8 +79,11 @@ int wsjson_parse(const char *buf, jsmntok_t *tokens, unsigned int max_tokens)
     return jsmn_parse(&p, buf, strlen(buf), tokens, max_tokens);
 }
 
-gboolean wsjson_unescape_json_string(const char *input, char *output)
+gboolean
+json_decode_string_inplace(char *text)
 {
+    const char *input = text;
+    char *output = text;
     while (*input) {
         char ch = *input++;
 

wsutil/wsjson.h

@@ -1,5 +1,5 @@
 /* wsjson.h
- * Utility to check if a payload is json using libjsmn
+ * JSON parsing functions.
  *
  * Copyright 2016, Dario Lombardo
  *
@@ -25,14 +25,15 @@ extern "C" {
 /**
  * Check if a buffer is json an returns true if it is.
  */
-WS_DLL_PUBLIC gboolean wsjson_is_valid_json(const guint8* buf, const size_t len);
+WS_DLL_PUBLIC gboolean json_validate(const guint8 *buf, const size_t len);
 
-WS_DLL_PUBLIC int wsjson_parse(const char *buf, jsmntok_t *tokens, unsigned int max_tokens);
+WS_DLL_PUBLIC int json_parse(const char *buf, jsmntok_t *tokens, unsigned int max_tokens);
 
 /**
- * Try to unescape input JSON string. output can be the same pointer as input, or must have the same buffer size as input.
+ * Decode the contents of a JSON string value by overwriting the input data.
+ * Returns TRUE on success and FALSE if invalid characters were encountered.
  */
-WS_DLL_PUBLIC gboolean wsjson_unescape_json_string(const char *input, char *output);
+WS_DLL_PUBLIC gboolean json_decode_string_inplace(char *text);
 
 #ifdef __cplusplus
 }