feature: Add option to skip invalid value types.

Co-authored-by: Jesper Lundgren <jesperlundgren@exosite.com>

5 files changed, 79 insertions, 16 deletions

diff --git a/.travis.yml b/.travis.yml
index b07f3dc..91f73ff 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -46,8 +46,8 @@ install:
     - cd ..
 
 script:
-  - cppcheck -i ./luajit2 -i --force --error-exitcode=1 --enable=warning . > build.log 2>&1 || (cat build.log && exit 1)
-  - sh runtests.sh
+  - cppcheck -i ./luajit2 --force --error-exitcode=1 --enable=warning . > build.log 2>&1 || (cat build.log && exit 1)
+  - bash runtests.sh
   - make
   - prove -Itests tests
   - TEST_LUA_USE_VALGRIND=1 prove -Itests tests > build.log 2>&1; export e=$?
diff --git a/lua-cjson-2.1.0.10-1.rockspec b/lua-cjson-2.1.0.11-1.rockspec
index 9ed4272..9ed4272 100644
--- a/lua-cjson-2.1.0.10-1.rockspec
+++ b/lua-cjson-2.1.0.11-1.rockspec
diff --git a/lua_cjson.c b/lua_cjson.c
index 94b0b46..42672de 100644
--- a/lua_cjson.c
+++ b/lua_cjson.c
@@ -82,6 +82,7 @@
 #define DEFAULT_ENCODE_EMPTY_TABLE_AS_OBJECT 1
 #define DEFAULT_DECODE_ARRAY_WITH_ARRAY_MT 0
 #define DEFAULT_ENCODE_ESCAPE_FORWARD_SLASH 1
+#define DEFAULT_ENCODE_SKIP_UNSUPPORTED_VALUE_TYPES 0
 
 #ifdef DISABLE_INVALID_NUMBERS
 #undef DEFAULT_DECODE_INVALID_NUMBERS
@@ -165,6 +166,7 @@ typedef struct {
     int decode_invalid_numbers;
     int decode_max_depth;
     int decode_array_with_array_mt;
+    int encode_skip_unsupported_value_types;
 } json_config_t;
 
 typedef struct {
@@ -356,6 +358,16 @@ static int json_cfg_decode_array_with_array_mt(lua_State *l)
     return 1;
 }
 
+/* Configure how to treat invalid types */
+static int json_cfg_encode_skip_unsupported_value_types(lua_State *l)
+{
+    json_config_t *cfg = json_arg_init(l, 1);
+
+    json_enum_option(l, 1, &cfg->encode_skip_unsupported_value_types, NULL, 1);
+
+    return 1;
+}
+
 /* Configures JSON encoding buffer persistence */
 static int json_cfg_encode_keep_buffer(lua_State *l)
 {
@@ -463,6 +475,7 @@ static void json_create_config(lua_State *l)
     cfg->encode_empty_table_as_object = DEFAULT_ENCODE_EMPTY_TABLE_AS_OBJECT;
     cfg->decode_array_with_array_mt = DEFAULT_DECODE_ARRAY_WITH_ARRAY_MT;
     cfg->encode_escape_forward_slash = DEFAULT_ENCODE_ESCAPE_FORWARD_SLASH;
+    cfg->encode_skip_unsupported_value_types = DEFAULT_ENCODE_SKIP_UNSUPPORTED_VALUE_TYPES;
 
 #if DEFAULT_ENCODE_KEEP_BUFFER > 0
     strbuf_init(&cfg->encode_buf, 0);
@@ -627,7 +640,7 @@ static void json_check_encode_depth(lua_State *l, json_config_t *cfg,
                current_depth);
 }
 
-static void json_append_data(lua_State *l, json_config_t *cfg,
+static int json_append_data(lua_State *l, json_config_t *cfg,
                              int current_depth, strbuf_t *json);
 
 /* json_append_array args:
@@ -637,19 +650,24 @@ static void json_append_data(lua_State *l, json_config_t *cfg,
 static void json_append_array(lua_State *l, json_config_t *cfg, int current_depth,
                               strbuf_t *json, int array_length)
 {
-    int comma, i;
+    int comma, i, json_pos, err;
 
     strbuf_append_char(json, '[');
 
     comma = 0;
     for (i = 1; i <= array_length; i++) {
-        if (comma)
+        json_pos = strbuf_length(json);
+        if (comma++ > 0)
             strbuf_append_char(json, ',');
-        else
-            comma = 1;
 
         lua_rawgeti(l, -1, i);
-        json_append_data(l, cfg, current_depth, json);
+        err = json_append_data(l, cfg, current_depth, json);
+        if (err) {
+            strbuf_set_length(json, json_pos);
+            if (comma == 1) {
+                comma = 0;
+            }
+        }
         lua_pop(l, 1);
     }
 
@@ -697,7 +715,7 @@ static void json_append_number(lua_State *l, json_config_t *cfg,
 static void json_append_object(lua_State *l, json_config_t *cfg,
                                int current_depth, strbuf_t *json)
 {
-    int comma, keytype;
+    int comma, keytype, json_pos, err;
 
     /* Object */
     strbuf_append_char(json, '{');
@@ -706,10 +724,9 @@ static void json_append_object(lua_State *l, json_config_t *cfg,
     /* table, startkey */
     comma = 0;
     while (lua_next(l, -2) != 0) {
-        if (comma)
+        json_pos = strbuf_length(json);
+        if (comma++ > 0)
             strbuf_append_char(json, ',');
-        else
-            comma = 1;
 
         /* table, key, value */
         keytype = lua_type(l, -2);
@@ -727,7 +744,14 @@ static void json_append_object(lua_State *l, json_config_t *cfg,
         }
 
         /* table, key, value */
-        json_append_data(l, cfg, current_depth, json);
+        err = json_append_data(l, cfg, current_depth, json);
+        if (err) {
+            strbuf_set_length(json, json_pos);
+            if (comma == 1) {
+                comma = 0;
+            }
+        }
+
         lua_pop(l, 1);
         /* table, key */
     }
@@ -735,8 +759,8 @@ static void json_append_object(lua_State *l, json_config_t *cfg,
     strbuf_append_char(json, '}');
 }
 
-/* Serialise Lua data into JSON string. */
-static void json_append_data(lua_State *l, json_config_t *cfg,
+/* Serialise Lua data into JSON string. Return 1 if error an error happened, else 0 */
+static int json_append_data(lua_State *l, json_config_t *cfg,
                              int current_depth, strbuf_t *json)
 {
     int len;
@@ -807,9 +831,15 @@ static void json_append_data(lua_State *l, json_config_t *cfg,
     default:
         /* Remaining types (LUA_TFUNCTION, LUA_TUSERDATA, LUA_TTHREAD,
          * and LUA_TLIGHTUSERDATA) cannot be serialised */
-        json_encode_exception(l, cfg, json, -1, "type not supported");
+        if (cfg->encode_skip_unsupported_value_types) {
+            return 1;
+        } else {
+            json_encode_exception(l, cfg, json, -1, "type not supported");
+        }
+
         /* never returns */
     }
+    return 0;
 }
 
 static int json_encode(lua_State *l)
@@ -1479,6 +1509,7 @@ static int lua_cjson_new(lua_State *l)
         { "encode_invalid_numbers", json_cfg_encode_invalid_numbers },
         { "decode_invalid_numbers", json_cfg_decode_invalid_numbers },
         { "encode_escape_forward_slash", json_cfg_encode_escape_forward_slash },
+        { "encode_skip_unsupported_value_types", json_cfg_encode_skip_unsupported_value_types },
         { "new", lua_cjson_new },
         { NULL, NULL }
     };
diff --git a/strbuf.h b/strbuf.h
index 5df0b7b..a98ee22 100644
--- a/strbuf.h
+++ b/strbuf.h
@@ -70,6 +70,7 @@ static char *strbuf_string(strbuf_t *s, int *len);
 static void strbuf_ensure_empty_length(strbuf_t *s, int len);
 static char *strbuf_empty_ptr(strbuf_t *s);
 static void strbuf_extend_length(strbuf_t *s, int len);
+static void strbuf_set_length(strbuf_t *s, int len);
 
 /* Update */
 extern void strbuf_append_fmt(strbuf_t *s, int len, const char *fmt, ...);
@@ -108,6 +109,11 @@ static inline char *strbuf_empty_ptr(strbuf_t *s)
     return s->buf + s->length;
 }
 
+static inline void strbuf_set_length(strbuf_t *s, int len)
+{
+    s->length = len;
+}
+
 static inline void strbuf_extend_length(strbuf_t *s, int len)
 {
     s->length += len;
diff --git a/tests/agentzh.t b/tests/agentzh.t
index 2e7c8ce..552630a 100644
--- a/tests/agentzh.t
+++ b/tests/agentzh.t
@@ -306,3 +306,29 @@ print(b)
 {"test":"http:\/\/google.com\/google"}
 {"test":"http://google.com/google"}
 {"test":"http:\/\/google.com\/google"}
+
+
+
+=== TEST 22: disable error on invalid type
+--- lua
+local cjson = require "cjson"
+local f = function (x) return 2*x end
+local res, err = pcall(cjson.encode, f)
+print(err)
+local t = {f = f, valid = "valid"}
+local res, err = pcall(cjson.encode, t)
+print(err)
+local arr = {"one", "two", f, "three"}
+local res, err = pcall(cjson.encode, arr)
+print(err)
+cjson.encode_skip_unsupported_value_types(true)
+print(cjson.encode(f))
+print(cjson.encode(t))
+print(cjson.encode(arr))
+--- out
+Cannot serialise function: type not supported
+Cannot serialise function: type not supported
+Cannot serialise function: type not supported
+
+{"valid":"valid"}
+["one","two","three"]