wsutil: split libjsmn.

The libjsmn was imported into the tree and enhanced with a new
function. This change splits it into the "original" libjsmn and
an addictional module wsjsmn that contains the new function.
This will make easier to port within the tree future versions
of the library.

Change-Id: I3f1caa91bee462e0767e5e18d0b6a10f0b1cad32
Reviewed-on: https://code.wireshark.org/review/17963
Petri-Dish: Peter Wu <peter@lekensteyn.nl>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Peter Wu <peter@lekensteyn.nl>

1 files changed, 80 insertions, 0 deletions

diff --git a/wsutil/wsjsmn.c b/wsutil/wsjsmn.c
new file mode 100644
index 0000000000..e18bd45a4e
--- /dev/null
+++ b/wsutil/wsjsmn.c
@@ -0,0 +1,80 @@
+/* wsjsmn.c
+ * Utility to check if a payload is json using libjsmn
+ *
+ * Copyright 2016, Dario Lombardo
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "wsjsmn.h"
+#include <wsutil/jsmn.h>
+#include "log.h"
+
+gboolean jsmn_is_json(const guint8* buf, const size_t len)
+{
+        /* We expect no more than 1024 tokens */
+        guint max_tokens = 1024;
+        jsmntok_t* t;
+        jsmn_parser p;
+        gboolean ret = TRUE;
+        int rcode;
+
+        t = g_new0(jsmntok_t, max_tokens);
+
+        if (!t)
+                return FALSE;
+
+        jsmn_init(&p);
+        rcode = jsmn_parse(&p, buf, len, t, max_tokens);
+        if (rcode < 0) {
+                switch (rcode) {
+                        case JSMN_ERROR_NOMEM:
+                                g_log(LOG_DOMAIN_MAIN, G_LOG_LEVEL_DEBUG, "jsmn: not enough tokens were provided");
+                                break;
+                        case JSMN_ERROR_INVAL:
+                                g_log(LOG_DOMAIN_MAIN, G_LOG_LEVEL_DEBUG, "jsmn: invalid character inside JSON string");
+                                break;
+                        case JSMN_ERROR_PART:
+                                g_log(LOG_DOMAIN_MAIN, G_LOG_LEVEL_DEBUG, "jsmn: the string is not a full JSON packet, "
+                                        "more bytes expected");
+                                break;
+                        default:
+                                g_log(LOG_DOMAIN_MAIN, G_LOG_LEVEL_DEBUG, "jsmn: unexpected error");
+                                break;
+                }
+                ret = FALSE;
+        }
+
+        g_free(t);
+
+        return ret;
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 4
+ * tab-width: 8
+ * indent-tabs-mode: t
+ * End:
+ *
+ * vi: set shiftwidth=4 tabstop=8 noexpandtab:
+ * :indentSize=4:tabSize=8:noTabs=false:
+ */