contributors: Add Alper Akcan

fix memory leak in cJSON_Duplicate

CMakeLists.txt

@@ -6,16 +6,16 @@ include(GNUInstallDirs)
 project(cJSON C)
 
 set(PROJECT_VERSION_MAJOR 1)
-set(PROJECT_VERSION_MINOR 0)
+set(PROJECT_VERSION_MINOR 1)
-set(PROJECT_VERSION_PATCH 2)
+set(PROJECT_VERSION_PATCH 0)
 set(CJSON_VERSION_SO 1)
 set(CJSON_UTILS_VERSION_SO 1)
 set(PROJECT_VERSION "${PROJECT_VERSION_MAJOR}.${PROJECT_VERSION_MINOR}.${PROJECT_VERSION_PATCH}")
 
-option(ENABLE_CUSTOM_COMPILER_FLAGS ON)
+option(ENABLE_CUSTOM_COMPILER_FLAGS "Enables custom compiler flags for Clang and GCC" ON)
 if (ENABLE_CUSTOM_COMPILER_FLAGS)
     if(("${CMAKE_C_COMPILER_ID}" MATCHES "GNU") OR ("${CMAKE_C_COMPILER_ID}" MATCHES "Clang"))
-        set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c89 -pedantic -Wall -Wextra -Werror -Wstrict-prototypes -Wwrite-strings")
+        set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c89 -pedantic -Wall -Wextra -Werror -Wstrict-prototypes -Wwrite-strings -Wshadow -Winit-self -Wcast-align -Wformat=2 -Wmissing-prototypes -Wstrict-overflow=2")
     endif()
 endif()
 

CONTRIBUTORS.md

@@ -2,6 +2,7 @@ Contributors
 ============
 
 * [Ajay Bhargav](https://github.com/ajaybhargav)
+* [Alper Akcan](https://github.com/alperakcan)
 * [Anton Sergeev](https://github.com/anton-sergeev)
 * [Christian Schulze](https://github.com/ChristianSch)
 * [Dave Gamble](https://github.com/DaveGamble)
@@ -15,6 +16,7 @@ Contributors
 * [IvanVoid](https://github.com/npi3pak)
 * [Jonathan Fether](https://github.com/jfether)
 * [Kevin Branigan](https://github.com/kbranigan)
+* [Kyle Chisholm](https://github.com/ChisholmKyle)
 * [Linus Wallgren](https://github.com/ecksun)
 * [Max Bruckner](https://github.com/FSMaxB)
 * Mike Pontillo
@@ -22,6 +24,7 @@ Contributors
 * [Rafael Leal Dias](https://github.com/rafaeldias)
 * [Rod Vagg](https://github.com/rvagg)
 * [Roland Meertens](https://github.com/rmeertens)
+* [Stephan Gatzka](https://github.com/gatzka)
 * [Weston Schmidt](https://github.com/schmidtw)
 
 And probably more people on [SourceForge](https://sourceforge.net/p/cjson/bugs/search/?q=status%3Aclosed-rejected+or+status%3Aclosed-out-of-date+or+status%3Awont-fix+or+status%3Aclosed-fixed+or+status%3Aclosed&page=0)

Makefile

@@ -5,9 +5,12 @@ UTILS_LIBNAME = libcjson_utils
 CJSON_TEST = cJSON_test
 UTILS_TEST = cJSON_test_utils
 
+CJSON_TEST_SRC = cJSON.c test.c
+UTILS_TEST_SRC = cJSON.c cJSON_Utils.c test_utils.c
+
 LDLIBS = -lm
 
-LIBVERSION = 1.0.2
+LIBVERSION = 1.1.0
 CJSON_SOVERSION = 1
 UTILS_SOVERSION = 1
 
@@ -20,7 +23,7 @@ INSTALL_LIBRARY_PATH = $(DESTDIR)$(PREFIX)/$(LIBRARY_PATH)
 
 INSTALL ?= cp -a
 
-R_CFLAGS = -fPIC -std=c89 -pedantic -Wall -Werror -Wstrict-prototypes -Wwrite-strings $(CFLAGS)
+R_CFLAGS = -fPIC -std=c89 -pedantic -Wall -Werror -Wstrict-prototypes -Wwrite-strings -Wshadow -Winit-self -Wcast-align -Wformat=2 -Wmissing-prototypes -Wstrict-overflow=2 $(CFLAGS)
 
 uname := $(shell sh -c 'uname -s 2>/dev/null || echo false')
 
@@ -62,15 +65,15 @@ test: tests
 	./$(UTILS_TEST)
 
 .c.o:
-	$(CC) -ansi -pedantic -c $(R_CFLAGS) $<
+	$(CC) -c $(R_CFLAGS) $<
 
 #tests
 #cJSON
-$(CJSON_TEST): cJSON.c cJSON.h test.c
+$(CJSON_TEST): $(CJSON_TEST_SRC) cJSON.h
-	$(CC) $^ -o $@ $(LDLIBS) -I.
+	$(CC) $(R_CFLAGS) $(CJSON_TEST_SRC)  -o $@ $(LDLIBS) -I.
 #cJSON_Utils
-$(UTILS_TEST): cJSON.c cJSON.h test.c
+$(UTILS_TEST): $(UTILS_TEST_SRC) cJSON.h cJSON_Utils.h
-	$(CC) $^ -o $@ $(LDLIBS) -I.
+	$(CC) $(R_CFLAGS) $(UTILS_TEST_SRC) -o $@ $(LDLIBS) -I.
 
 #static libraries
 #cJSON

cJSON.c

@@ -244,6 +244,7 @@ typedef struct
     char *buffer;
     int length;
     int offset;
+    cjbool noalloc;
 } printbuffer;
 
 /* realloc printbuffer if necessary to have at least "needed" bytes more */
@@ -261,6 +262,10 @@ static char* ensure(printbuffer *p, int needed)
         return p->buffer + p->offset;
     }
 
+    if (p->noalloc) {
+        return NULL;
+    }
+
     newsize = pow2gt(needed);
     newbuffer = (char*)cJSON_malloc(newsize);
     if (!newbuffer)
@@ -712,8 +717,9 @@ static char *print_string_ptr(const char *str, printbuffer *p)
 
     ptr = str;
     /* calculate additional space that is needed for escaping */
-    while ((token = *ptr) && ++len)
+    while ((token = *ptr))
     {
+        ++len;
         if (strchr("\"\\\b\f\n\r\t", token))
         {
             len++; /* +1 for the backslash */
@@ -882,10 +888,20 @@ char *cJSON_PrintBuffered(const cJSON *item, int prebuffer, cjbool fmt)
     }
     p.length = prebuffer;
     p.offset = 0;
+    p.noalloc = false;
 
     return print_value(item, 0, fmt, &p);
 }
 
+int cJSON_PrintPreallocated(cJSON *item,char *buf, const int len, const cjbool fmt)
+{
+    printbuffer p;
+    p.buffer = buf;
+    p.length = len;
+    p.offset = 0;
+    p.noalloc = true;
+    return print_value(item,0,fmt,&p) != NULL;
+}
 
 /* Parser core - when encountering text, process appropriately. */
 static const char *parse_value(cJSON *item, const char *value, const char **ep)
@@ -1137,7 +1153,10 @@ static char *print_array(const cJSON *item, int depth, cjbool fmt, printbuffer *
         child = item->child;
         while (child && !fail)
         {
-            print_value(child, depth + 1, fmt, p);
+            if (!print_value(child, depth + 1, fmt, p))
+            {
+                return NULL;
+            }
             p->offset = update(p);
             if (child->next)
             {
@@ -1434,7 +1453,10 @@ static char *print_object(const cJSON *item, int depth, cjbool fmt, printbuffer
             }
 
             /* print key */
-            print_string_ptr(child->string, p);
+            if (!print_string_ptr(child->string, p))
+            {
+                return NULL;
+            }
             p->offset = update(p);
 
             len = fmt ? 2 : 1;
@@ -1451,7 +1473,10 @@ static char *print_object(const cJSON *item, int depth, cjbool fmt, printbuffer
             p->offset+=len;
 
             /* print value */
-            print_value(child, depth, fmt, p);
+            if (!print_value(child, depth, fmt, p))
+            {
+                return NULL;
+            };
             p->offset = update(p);
 
             /* print comma if not last */
@@ -2128,7 +2153,7 @@ cJSON *cJSON_Duplicate(const cJSON *item, cjbool recurse)
     }
     if (item->string)
     {
-        newitem->string = cJSON_strdup(item->string);
+        newitem->string = (item->type&cJSON_StringIsConst) ? item->string : cJSON_strdup(item->string);
         if (!newitem->string)
         {
             cJSON_Delete(newitem);

cJSON.h

@@ -83,6 +83,8 @@ extern char  *cJSON_Print(const cJSON *item);
 extern char  *cJSON_PrintUnformatted(const cJSON *item);
 /* Render a cJSON entity to text using a buffered strategy. prebuffer is a guess at the final size. guessing well reduces reallocation. fmt=0 gives unformatted, =1 gives formatted */
 extern char *cJSON_PrintBuffered(const cJSON *item, int prebuffer, int fmt);
+/* Render a cJSON entity to text using a buffer already allocated in memory with length buf_len. Returns 1 on success and 0 on failure. */
+extern int cJSON_PrintPreallocated(cJSON *item, char *buf, const int len, const int fmt);
 /* Delete a cJSON entity and all subentities. */
 extern void   cJSON_Delete(cJSON *c);
 
@@ -115,7 +117,10 @@ extern cJSON *cJSON_CreateStringArray(const char **strings, int count);
 /* Append item to the specified array/object. */
 extern void cJSON_AddItemToArray(cJSON *array, cJSON *item);
 extern void	cJSON_AddItemToObject(cJSON *object, const char *string, cJSON *item);
-extern void	cJSON_AddItemToObjectCS(cJSON *object, const char *string, cJSON *item);	/* Use this when string is definitely const (i.e. a literal, or as good as), and will definitely survive the cJSON object */
+/* Use this when string is definitely const (i.e. a literal, or as good as), and will definitely survive the cJSON object.
+ * WARNING: When this function was used, make sure to always check that (item->type & cJSON_StringIsConst) is zero before
+ * writing to `item->string` */
+extern void	cJSON_AddItemToObjectCS(cJSON *object, const char *string, cJSON *item);
 /* Append reference to item to the specified array/object. Use this when you want to add an existing cJSON to a new cJSON, but don't want to corrupt your existing cJSON. */
 extern void cJSON_AddItemReferenceToArray(cJSON *array, cJSON *item);
 extern void	cJSON_AddItemReferenceToObject(cJSON *object, const char *string, cJSON *item);

test.c

@@ -22,10 +22,11 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include "cJSON.h"
 
 /* Parse text to JSON, then render back to text, and print! */
-void doit(char *text)
+static void doit(char *text)
 {
     char *out = NULL;
     cJSON *json = NULL;
@@ -44,8 +45,9 @@ void doit(char *text)
     }
 }
 
+#if 0
 /* Read a file, parse, render back, etc. */
-void dofile(char *filename)
+static void dofile(char *filename)
 {
     FILE *f = NULL;
     long len = 0;
@@ -59,6 +61,11 @@ void dofile(char *filename)
     fseek(f, 0, SEEK_SET);
 
     data = (char*)malloc(len + 1);
+    if (data == NULL)
+    {
+        printf("Failed to allocate memory.\n");
+        exit(1);
+    }
 
     fread(data, 1, len, f);
     data[len] = '\0';
@@ -67,6 +74,7 @@ void dofile(char *filename)
     doit(data);
     free(data);
 }
+#endif
 
 /* Used by some code below as an example datatype. */
 struct record
@@ -81,8 +89,75 @@ struct record
     const char *country;
 };
 
+
 /* Create a bunch of objects as demonstration. */
-void create_objects(void)
+static int print_preallocated(cJSON *root)
+{
+    /* declarations */
+    char *out = NULL;
+    char *buf = NULL;
+    char *buf_fail = NULL;
+    int len = 0;
+    int len_fail = 0;
+
+    /* formatted print */
+    out = cJSON_Print(root);
+
+    /* create buffer to succeed */
+    /* the extra 64 bytes are in case a floating point value is printed */
+    len = strlen(out) + 64;
+    buf = malloc(len);
+    if (buf == NULL)
+    {
+        printf("Failed to allocate memory.\n");
+        exit(1);
+    }
+
+    /* create buffer to fail */
+    len_fail = strlen(out);
+    buf_fail = malloc(len_fail);
+    if (buf_fail == NULL)
+    {
+        printf("Failed to allocate memory.\n");
+        exit(1);
+    }
+
+    /* Print to buffer */
+    if (!cJSON_PrintPreallocated(root, buf, len, 1)) {
+        printf("cJSON_PrintPreallocated failed!\n");
+        if (strcmp(out, buf) != 0) {
+            printf("cJSON_PrintPreallocated not the same as cJSON_Print!\n");
+            printf("cJSON_Print result:\n%s\n", out);
+            printf("cJSON_PrintPreallocated result:\n%s\n", buf);
+        }
+        free(out);
+        free(buf_fail);
+        free(buf);
+        return -1;
+    }
+
+    /* success */
+    printf("%s\n", buf);
+
+    /* force it to fail */
+    if (cJSON_PrintPreallocated(root, buf_fail, len_fail, 1)) {
+        printf("cJSON_PrintPreallocated failed to show error with insufficient memory!\n");
+        printf("cJSON_Print result:\n%s\n", out);
+        printf("cJSON_PrintPreallocated result:\n%s\n", buf_fail);
+        free(out);
+        free(buf_fail);
+        free(buf);
+        return -1;
+    }
+
+    free(out);
+    free(buf_fail);
+    free(buf);
+    return 0;
+}
+
+/* Create a bunch of objects as demonstration. */
+static void create_objects(void)
 {
     /* declare a few. */
     cJSON *root = NULL;
@@ -90,7 +165,6 @@ void create_objects(void)
     cJSON *img = NULL;
     cJSON *thm = NULL;
     cJSON *fld = NULL;
-    char *out = NULL;
     int i = 0;
 
     /* Our "days of the week" array: */
@@ -152,21 +226,20 @@ void create_objects(void)
     cJSON_AddNumberToObject(fmt, "frame rate", 24);
 
     /* Print to text */
-    out = cJSON_Print(root);
+    if (print_preallocated(root) != 0) {
-    /* Delete the cJSON */
+        cJSON_Delete(root);
+        exit(EXIT_FAILURE);
+    }
     cJSON_Delete(root);
-    /* print it */
-    printf("%s\n",out);
-    /* release the string */
-    free(out);
 
     /* Our "days of the week" array: */
     root = cJSON_CreateStringArray(strings, 7);
 
-    out = cJSON_Print(root);
+    if (print_preallocated(root) != 0) {
+        cJSON_Delete(root);
+        exit(EXIT_FAILURE);
+    }
     cJSON_Delete(root);
-    printf("%s\n", out);
-    free(out);
 
     /* Our matrix: */
     root = cJSON_CreateArray();
@@ -177,11 +250,11 @@ void create_objects(void)
 
     /* cJSON_ReplaceItemInArray(root, 1, cJSON_CreateString("Replacement")); */
 
-    out = cJSON_Print(root);
+    if (print_preallocated(root) != 0) {
+        cJSON_Delete(root);
+        exit(EXIT_FAILURE);
+    }
     cJSON_Delete(root);
-    printf("%s\n", out);
-    free(out);
-
 
     /* Our "gallery" item: */
     root = cJSON_CreateObject();
@@ -195,13 +268,13 @@ void create_objects(void)
     cJSON_AddStringToObject(thm, "Width", "100");
     cJSON_AddItemToObject(img, "IDs", cJSON_CreateIntArray(ids, 4));
 
-    out = cJSON_Print(root);
+    if (print_preallocated(root) != 0) {
+        cJSON_Delete(root);
+        exit(EXIT_FAILURE);
+    }
     cJSON_Delete(root);
-    printf("%s\n", out);
-    free(out);
 
     /* Our array of "records": */
-
     root = cJSON_CreateArray();
     for (i = 0; i < 2; i++)
     {
@@ -218,17 +291,20 @@ void create_objects(void)
 
     /* cJSON_ReplaceItemInObject(cJSON_GetArrayItem(root, 1), "City", cJSON_CreateIntArray(ids, 4)); */
 
-    out = cJSON_Print(root);
+    if (print_preallocated(root) != 0) {
+        cJSON_Delete(root);
+        exit(EXIT_FAILURE);
+    }
     cJSON_Delete(root);
-    printf("%s\n", out);
-    free(out);
 
     root = cJSON_CreateObject();
     cJSON_AddNumberToObject(root, "number", 1.0 / zero);
-    out = cJSON_Print(root);
+
+    if (print_preallocated(root) != 0) {
+        cJSON_Delete(root);
+        exit(EXIT_FAILURE);
+    }
     cJSON_Delete(root);
-    printf("%s\n", out);
-    free(out);
 }
 
 int main(void)

test_utils.c

@@ -96,14 +96,14 @@ int main(void)
     printf("JSON Apply Patch Tests\n");
     for (i = 0; i < 15; i++)
     {
-        cJSON *object = cJSON_Parse(patches[i][0]);
+        cJSON *object_to_be_patched = cJSON_Parse(patches[i][0]);
         cJSON *patch = cJSON_Parse(patches[i][1]);
-        int err = cJSONUtils_ApplyPatches(object, patch);
+        int err = cJSONUtils_ApplyPatches(object_to_be_patched, patch);
-        char *output = cJSON_Print(object);
+        char *output = cJSON_Print(object_to_be_patched);
         printf("Test %d (err %d):\n%s\n\n", i + 1, err, output);
 
         free(output);
-        cJSON_Delete(object);
+        cJSON_Delete(object_to_be_patched);
         cJSON_Delete(patch);
     }
 
@@ -168,19 +168,19 @@ int main(void)
     printf("JSON Merge Patch tests\n");
     for (i = 0; i < 15; i++)
     {
-        cJSON *object = cJSON_Parse(merges[i][0]);
+        cJSON *object_to_be_merged = cJSON_Parse(merges[i][0]);
         cJSON *patch = cJSON_Parse(merges[i][1]);
-        char *before = cJSON_PrintUnformatted(object);
+        char *before_merge = cJSON_PrintUnformatted(object_to_be_merged);
         patchtext = cJSON_PrintUnformatted(patch);
-        printf("Before: [%s] -> [%s] = ", before, patchtext);
+        printf("Before: [%s] -> [%s] = ", before_merge, patchtext);
-        object = cJSONUtils_MergePatch(object, patch);
+        object_to_be_merged = cJSONUtils_MergePatch(object_to_be_merged, patch);
-        after = cJSON_PrintUnformatted(object);
+        after = cJSON_PrintUnformatted(object_to_be_merged);
         printf("[%s] vs [%s] (%s)\n", after, merges[i][2], strcmp(after, merges[i][2]) ? "FAIL" : "OK");
 
-        free(before);
+        free(before_merge);
         free(patchtext);
         free(after);
-        cJSON_Delete(object);
+        cJSON_Delete(object_to_be_merged);
         cJSON_Delete(patch);
     }