jansson/test/suites/api/test_memory_funcs.c

#include <string.h>
#include <jansson.h>

#include "util.h"

static int malloc_called = 0;
static int free_called = 0;
static size_t malloc_used = 0;

/* helpers */
static void create_and_free_complex_object()
{
    json_t *obj;

    obj = json_pack("{s:i,s:n,s:b,s:b,s:{s:s},s:[i,i,i]}",
                    "foo", 42,
                    "bar",
                    "baz", 1,
                    "qux", 0,
                    "alice", "bar", "baz",
                    "bob", 9, 8, 7);

    json_decref(obj);
}

static void create_and_free_object_with_oom()
{
    int i;
    char key[4];
    json_t *obj = json_object();

    for (i = 0; i < 10; i++)
    {
        snprintf(key, sizeof key, "%d", i);
        json_object_set_new(obj, key, json_integer(i));
    }

    json_decref(obj);
}

static void *my_malloc(size_t size)
{
    malloc_called = 1;
    return malloc(size);
}

static void my_free(void *ptr)
{
    free_called = 1;
    free(ptr);
}

static void test_simple()
{
    json_malloc_t mfunc = NULL;
    json_free_t ffunc = NULL;

    json_set_alloc_funcs(my_malloc, my_free);
    json_get_alloc_funcs(&mfunc, &ffunc);
    create_and_free_complex_object();

    if (malloc_called != 1 || free_called != 1
        || mfunc != my_malloc || ffunc != my_free)
        fail("Custom allocation failed");
}


static void *oom_malloc(size_t size)
{
    if (malloc_used + size > 800)
        return NULL;

    malloc_used += size;
    return malloc(size);
}

static void oom_free(void *ptr)
{
    free_called++;
    free(ptr);
}

static void test_oom()
{
    free_called = 0;
    json_set_alloc_funcs(oom_malloc, oom_free);
    create_and_free_object_with_oom();

    if (free_called == 0)
        fail("Allocation with OOM failed");
}


/*
  Test the secure memory functions code given in the API reference
  documentation, but by using plain memset instead of
  guaranteed_memset().
*/

static void *secure_malloc(size_t size)
{
    /* Store the memory area size in the beginning of the block */
    void *ptr = malloc(size + 8);
    *((size_t *)ptr) = size;
    return (char *)ptr + 8;
}

static void secure_free(void *ptr)
{
    size_t size;

    ptr = (char *)ptr - 8;
    size = *((size_t *)ptr);

    /*guaranteed_*/memset(ptr, 0, size + 8);
    free(ptr);
}

static void test_secure_funcs(void)
{
    json_set_alloc_funcs(secure_malloc, secure_free);
    create_and_free_complex_object();
}

static void test_bad_args(void)
{
    /* The result of this test is not crashing. */
    json_get_alloc_funcs(NULL, NULL);
}

static void run_tests()
{
    test_simple();
    test_secure_funcs();
    test_oom();
    test_bad_args();
}