Merge pull request #584 from DiUS/cjson-lua-mem-wrap

Improvements to cjson memory handling, Note that when cjson fails a memory allocation, it leaks a bit of memory, it's possible to detect that it did fail, and schedule a restart.

app/cjson/cjson_mem.c

@@ -0,0 +1,28 @@
+#include "cjson_mem.h"
+#include "../lua/lauxlib.h"
+#include <c_stdlib.h>
+
+static lua_State *gL;
+static const char errfmt[] = "cjson %salloc: out of mem (%d bytes)";
+
+void cjson_mem_setlua (lua_State *L)
+{
+  gL = L;
+}
+
+void *cjson_mem_malloc (uint32_t sz)
+{
+  void *p = (void*)c_malloc (sz);
+  if (!p && gL)
+    luaL_error (gL, errfmt, "m", sz);
+  return p;
+}
+
+
+void *cjson_mem_realloc (void *o, uint32_t sz)
+{
+  void *p = (void*)c_realloc (o, sz);
+  if (!p && gL)
+    luaL_error (gL, errfmt, "re", sz);
+  return p;
+}

app/cjson/cjson_mem.h

@@ -0,0 +1,11 @@
+#ifndef _CJSON_MEM_H_
+#define _CJSON_MEM_H_
+
+#include "../lua/lua.h"
+
+void cjson_mem_setlua (lua_State *L);
+
+void *cjson_mem_malloc (uint32_t sz);
+void *cjson_mem_realloc (void *p, uint32_t sz);
+
+#endif

app/cjson/strbuf.c

@@ -28,6 +28,7 @@
 #include "c_string.h"
 
 #include "strbuf.h"
+#include "cjson_mem.h"
 
 int strbuf_init(strbuf_t *s, int len)
 {
@@ -46,7 +47,7 @@ int strbuf_init(strbuf_t *s, int len)
     s->reallocs = 0;
     s->debug = 0;
 
-    s->buf = (char *)c_malloc(size);
+    s->buf = (char *)cjson_mem_malloc(size);
     if (!s->buf){
         NODE_ERR("not enough memory\n");
         return -1;
@@ -60,7 +61,7 @@ strbuf_t *strbuf_new(int len)
 {
     strbuf_t *s;
 
-    s = (strbuf_t *)c_malloc(sizeof(strbuf_t));
+    s = (strbuf_t *)cjson_mem_malloc(sizeof(strbuf_t));
     if (!s){
         NODE_ERR("not enough memory\n");
         return NULL;
@@ -150,7 +151,7 @@ static int calculate_new_size(strbuf_t *s, int len)
             newsize *= -s->increment;
     } else {
         /* Linear sizing */
-        newsize = ((newsize + s->increment - 1) / s->increment) * s->increment;
+        newsize = (((reqsize -1) / s->increment) + 1) * s->increment;
     }
 
     return newsize;
@@ -170,7 +171,7 @@ int strbuf_resize(strbuf_t *s, int len)
                 (long)s, s->size, newsize);
     }
 
-    s->buf = (char *)c_realloc(s->buf, newsize);
+    s->buf = (char *)cjson_mem_realloc(s->buf, newsize);
     if (!s->buf){
         NODE_ERR("not enough memory");
         return -1;

app/cjson/strbuf.h

@@ -24,6 +24,7 @@
 
 #include "c_stdlib.h"
 #include "c_stdarg.h"
+#include "user_config.h"
 
 /* Size: Total bytes allocated to *buf
  * Length: String length, excluding optional NULL terminator.

app/include/user_config.h

@@ -68,4 +68,6 @@
 #define LED_LOW_COUNT_DEFAULT 0
 #endif
 
+#define STRBUF_DEFAULT_INCREMENT 32
+
 #endif	/* __USER_CONFIG_H__ */

app/modules/cjson.c

@@ -45,6 +45,7 @@
 #include "flash_api.h"
 
 #include "strbuf.h"
+#include "cjson_mem.h"
 
 #define FPCONV_G_FMT_BUFSIZE   32
 #define fpconv_strtod c_strtod
@@ -1461,7 +1462,7 @@ static int json_decode(lua_State *l)
      * string must be smaller than the entire json string */
     json.tmp = strbuf_new(json_len);
     if(json.tmp == NULL){
-        return luaL_error(l, "not enought memory");
+        return luaL_error(l, "not enough memory");
     }
 
     json_next_token(&json, &token);
@@ -1552,6 +1553,8 @@ const LUA_REG_TYPE cjson_map[] =
 
 LUALIB_API int luaopen_cjson( lua_State *L )
 {
+  cjson_mem_setlua (L);
+
   /* Initialise number conversions */
   // fpconv_init();         // not needed for a specific cpu.
   if(-1==cfg_init(&_cfg)){