zmalloc.c

   1 /* zmalloc - total amount of allocated memory aware version of malloc()
   2  *
   3  * Copyright (c) 2009-2010, Salvatore Sanfilippo <antirez at gmail dot com>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are met:
   8  *
   9  *   * Redistributions of source code must retain the above copyright notice,
  10  *     this list of conditions and the following disclaimer.
  11  *   * Redistributions in binary form must reproduce the above copyright
  12  *     notice, this list of conditions and the following disclaimer in the
  13  *     documentation and/or other materials provided with the distribution.
  14  *   * Neither the name of Redis nor the names of its contributors may be used
  15  *     to endorse or promote products derived from this software without
  16  *     specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <pthread.h>
  35 #include "config.h"
  36
  37 #if defined(__sun)
  38 #define PREFIX_SIZE sizeof(long long)
  39 #else
  40 #define PREFIX_SIZE sizeof(size_t)
  41 #endif
  42
  43 #define increment_used_memory(__n) do { \
  44     size_t _n = (__n); \
  45     if (_n&(sizeof(long)-1)) _n += sizeof(long)-(_n&(sizeof(long)-1)); \
  46     if (zmalloc_thread_safe) { \
  47         pthread_mutex_lock(&used_memory_mutex);  \
  48         used_memory += _n; \
  49         pthread_mutex_unlock(&used_memory_mutex); \
  50     } else { \
  51         used_memory += _n; \
  52     } \
  53 } while(0)
  54
  55 #define decrement_used_memory(__n) do { \
  56     size_t _n = (__n); \
  57     if (_n&(sizeof(long)-1)) _n += sizeof(long)-(_n&(sizeof(long)-1)); \
  58     if (zmalloc_thread_safe) { \
  59         pthread_mutex_lock(&used_memory_mutex);  \
  60         used_memory -= _n; \
  61         pthread_mutex_unlock(&used_memory_mutex); \
  62     } else { \
  63         used_memory -= _n; \
  64     } \
  65 } while(0)
  66
  67 static size_t used_memory = 0;
  68 static int zmalloc_thread_safe = 0;
  69 pthread_mutex_t used_memory_mutex = PTHREAD_MUTEX_INITIALIZER;
  70
  71 static void zmalloc_oom(size_t size) {
  72     fprintf(stderr, "zmalloc: Out of memory trying to allocate %zu bytes\n",
  73         size);
  74     fflush(stderr);
  75     abort();
  76 }
  77
  78 void *zmalloc(size_t size) {
  79     void *ptr = malloc(size+PREFIX_SIZE);
  80
  81     if (!ptr) zmalloc_oom(size);
  82 #ifdef HAVE_MALLOC_SIZE
  83     increment_used_memory(redis_malloc_size(ptr));
  84     return ptr;
  85 #else
  86     *((size_t*)ptr) = size;
  87     increment_used_memory(size+PREFIX_SIZE);
  88     return (char*)ptr+PREFIX_SIZE;
  89 #endif
  90 }
  91
  92 void *zrealloc(void *ptr, size_t size) {
  93 #ifndef HAVE_MALLOC_SIZE
  94     void *realptr;
  95 #endif
  96     size_t oldsize;
  97     void *newptr;
  98
  99     if (ptr == NULL) return zmalloc(size);
 100 #ifdef HAVE_MALLOC_SIZE
 101     oldsize = redis_malloc_size(ptr);
 102     newptr = realloc(ptr,size);
 103     if (!newptr) zmalloc_oom(size);
 104
 105     decrement_used_memory(oldsize);
 106     increment_used_memory(redis_malloc_size(newptr));
 107     return newptr;
 108 #else
 109     realptr = (char*)ptr-PREFIX_SIZE;
 110     oldsize = *((size_t*)realptr);
 111     newptr = realloc(realptr,size+PREFIX_SIZE);
 112     if (!newptr) zmalloc_oom(size);
 113
 114     *((size_t*)newptr) = size;
 115     decrement_used_memory(oldsize);
 116     increment_used_memory(size);
 117     return (char*)newptr+PREFIX_SIZE;
 118 #endif
 119 }
 120
 121 void zfree(void *ptr) {
 122 #ifndef HAVE_MALLOC_SIZE
 123     void *realptr;
 124     size_t oldsize;
 125 #endif
 126
 127     if (ptr == NULL) return;
 128 #ifdef HAVE_MALLOC_SIZE
 129     decrement_used_memory(redis_malloc_size(ptr));
 130     free(ptr);
 131 #else
 132     realptr = (char*)ptr-PREFIX_SIZE;
 133     oldsize = *((size_t*)realptr);
 134     decrement_used_memory(oldsize+PREFIX_SIZE);
 135     free(realptr);
 136 #endif
 137 }
 138
 139 char *zstrdup(const char *s) {
 140     size_t l = strlen(s)+1;
 141     char *p = zmalloc(l);
 142
 143     memcpy(p,s,l);
 144     return p;
 145 }
 146
 147 size_t zmalloc_used_memory(void) {
 148     size_t um;
 149
 150     if (zmalloc_thread_safe) pthread_mutex_lock(&used_memory_mutex);
 151     um = used_memory;
 152     if (zmalloc_thread_safe) pthread_mutex_unlock(&used_memory_mutex);
 153     return um;
 154 }
 155
 156 void zmalloc_enable_thread_safeness(void) {
 157     zmalloc_thread_safe = 1;
 158 }