zmalloc.c

   1 /* zmalloc - total amount of allocated memory aware version of malloc()
   2  *
   3  * Copyright (c) 2006-2009, 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     if (zmalloc_thread_safe) { \
  45         pthread_mutex_lock(&used_memory_mutex);  \
  46         used_memory += _n; \
  47         pthread_mutex_unlock(&used_memory_mutex); \
  48     } else { \
  49         used_memory += _n; \
  50     } \
  51 } while(0)
  52
  53 #define decrement_used_memory(_n) do { \
  54     if (zmalloc_thread_safe) { \
  55         pthread_mutex_lock(&used_memory_mutex);  \
  56         used_memory -= _n; \
  57         pthread_mutex_unlock(&used_memory_mutex); \
  58     } else { \
  59         used_memory -= _n; \
  60     } \
  61 } while(0)
  62
  63 static size_t used_memory = 0;
  64 static int zmalloc_thread_safe = 0;
  65 pthread_mutex_t used_memory_mutex = PTHREAD_MUTEX_INITIALIZER;
  66
  67 static void zmalloc_oom(size_t size) {
  68     fprintf(stderr, "zmalloc: Out of memory trying to allocate %zu bytes\n",
  69         size);
  70     fflush(stderr);
  71     abort();
  72 }
  73
  74 void *zmalloc(size_t size) {
  75     void *ptr = malloc(size+PREFIX_SIZE);
  76
  77     if (!ptr) zmalloc_oom(size);
  78 #ifdef HAVE_MALLOC_SIZE
  79     increment_used_memory(redis_malloc_size(ptr));
  80     return ptr;
  81 #else
  82     *((size_t*)ptr) = size;
  83     increment_used_memory(size+PREFIX_SIZE);
  84     return (char*)ptr+PREFIX_SIZE;
  85 #endif
  86 }
  87
  88 void *zrealloc(void *ptr, size_t size) {
  89 #ifndef HAVE_MALLOC_SIZE
  90     void *realptr;
  91 #endif
  92     size_t oldsize;
  93     void *newptr;
  94
  95     if (ptr == NULL) return zmalloc(size);
  96 #ifdef HAVE_MALLOC_SIZE
  97     oldsize = redis_malloc_size(ptr);
  98     newptr = realloc(ptr,size);
  99     if (!newptr) zmalloc_oom(size);
 100
 101     decrement_used_memory(oldsize);
 102     increment_used_memory(redis_malloc_size(newptr));
 103     return newptr;
 104 #else
 105     realptr = (char*)ptr-PREFIX_SIZE;
 106     oldsize = *((size_t*)realptr);
 107     newptr = realloc(realptr,size+PREFIX_SIZE);
 108     if (!newptr) zmalloc_oom(size);
 109
 110     *((size_t*)newptr) = size;
 111     decrement_used_memory(oldsize);
 112     increment_used_memory(size);
 113     return (char*)newptr+PREFIX_SIZE;
 114 #endif
 115 }
 116
 117 void zfree(void *ptr) {
 118 #ifndef HAVE_MALLOC_SIZE
 119     void *realptr;
 120     size_t oldsize;
 121 #endif
 122
 123     if (ptr == NULL) return;
 124 #ifdef HAVE_MALLOC_SIZE
 125     decrement_used_memory(redis_malloc_size(ptr));
 126     free(ptr);
 127 #else
 128     realptr = (char*)ptr-PREFIX_SIZE;
 129     oldsize = *((size_t*)realptr);
 130     decrement_used_memory(oldsize+PREFIX_SIZE);
 131     free(realptr);
 132 #endif
 133 }
 134
 135 char *zstrdup(const char *s) {
 136     size_t l = strlen(s)+1;
 137     char *p = zmalloc(l);
 138
 139     memcpy(p,s,l);
 140     return p;
 141 }
 142
 143 size_t zmalloc_used_memory(void) {
 144     size_t um;
 145
 146     if (zmalloc_thread_safe) pthread_mutex_lock(&used_memory_mutex);
 147     um = used_memory;
 148     if (zmalloc_thread_safe) pthread_mutex_unlock(&used_memory_mutex);
 149     return um;
 150 }
 151
 152 void zmalloc_enable_thread_safeness(void) {
 153     zmalloc_thread_safe = 1;
 154 }