/* zmalloc - total amount of allocated memory aware version of malloc()
 *
 * Copyright (c) 2006-2009, Salvatore Sanfilippo <antirez at gmail dot com>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *   * Neither the name of Redis nor the names of its contributors may be used
 *     to endorse or promote products derived from this software without
 *     specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdlib.h>
#include <string.h>

#ifdef __APPLE__
#include <malloc/malloc.h>
#define HAVE_MALLOC_SIZE
#define redis_malloc_size(p) malloc_size(p)
#endif

static size_t used_memory = 0;

void *zmalloc(size_t size) {
    void *ptr = malloc(size+sizeof(size_t));

    if (!ptr) return NULL;
#ifdef HAVE_MALLOC_SIZE
    used_memory += redis_malloc_size(ptr);
    return ptr;
#else
    *((size_t*)ptr) = size;
    used_memory += size+sizeof(size_t);
    return (char*)ptr+sizeof(size_t);
#endif
}

void *zrealloc(void *ptr, size_t size) {
#ifndef HAVE_MALLOC_SIZE
    void *realptr;
#endif
    size_t oldsize;
    void *newptr;

    if (ptr == NULL) return zmalloc(size);
#ifdef HAVE_MALLOC_SIZE
    oldsize = redis_malloc_size(ptr);
    newptr = realloc(ptr,size);
    if (!newptr) return NULL;

    used_memory -= oldsize;
    used_memory += redis_malloc_size(newptr);
    return newptr;
#else
    realptr = (char*)ptr-sizeof(size_t);
    oldsize = *((size_t*)realptr);
    newptr = realloc(realptr,size+sizeof(size_t));
    if (!newptr) return NULL;

    *((size_t*)newptr) = size;
    used_memory -= oldsize;
    used_memory += size;
    return (char*)newptr+sizeof(size_t);
#endif
}

void zfree(void *ptr) {
#ifndef HAVE_MALLOC_SIZE
    void *realptr;
    size_t oldsize;
#endif

    if (ptr == NULL) return;
#ifdef HAVE_MALLOC_SIZE
    used_memory -= redis_malloc_size(ptr);
    free(ptr);
#else
    realptr = (char*)ptr-sizeof(size_t);
    oldsize = *((size_t*)realptr);
    used_memory -= oldsize+sizeof(size_t);
    free(realptr);
#endif
}

char *zstrdup(const char *s) {
    size_t l = strlen(s)+1;
    char *p = zmalloc(l);

    memcpy(p,s,l);
    return p;
}

size_t zmalloc_used_memory(void) {
    return used_memory;
}