git.m6w6.name Git - m6w6/libmemcached/blob - libmemcached/memcached_string.c

   1 /* LibMemcached
   2  * Copyright (C) 2006-2009 Brian Aker
   3  * All rights reserved.
   4  *
   5  * Use and distribution licensed under the BSD license.  See
   6  * the COPYING file in the parent directory for full text.
   7  *
   8  */
   9
  10 #include "common.h"
  11
  12 inline static memcached_return_t _string_check(memcached_string_st *string, size_t need)
  13 {
  14   if (need && need > (size_t)(string->current_size - (size_t)(string->end - string->string)))
  15   {
  16     size_t current_offset= (size_t) (string->end - string->string);
  17     char *new_value;
  18     size_t adjust;
  19     size_t new_size;
  20
  21     /* This is the block multiplier. To keep it larger and surive division errors we must round it up */
  22     adjust= (need - (size_t)(string->current_size - (size_t)(string->end - string->string))) / string->block_size;
  23     adjust++;
  24
  25     new_size= sizeof(char) * (size_t)((adjust * string->block_size) + string->current_size);
  26     /* Test for overflow */
  27     if (new_size < need)
  28       return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
  29
  30     new_value= string->root->call_realloc(string->root, string->string, new_size);
  31
  32     if (new_value == NULL)
  33       return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
  34
  35     string->string= new_value;
  36     string->end= string->string + current_offset;
  37
  38     string->current_size+= (string->block_size * adjust);
  39   }
  40
  41   return MEMCACHED_SUCCESS;
  42 }
  43
  44 memcached_string_st *memcached_string_create(memcached_st *memc, memcached_string_st *string, size_t initial_size)
  45 {
  46   memcached_return_t rc;
  47
  48   /* Saving malloc calls :) */
  49   if (string)
  50   {
  51     WATCHPOINT_ASSERT(memc->options.is_safe && string->options.is_initialized == false);
  52
  53     memset(string, 0, sizeof(memcached_string_st));
  54   }
  55   else
  56   {
  57     string= memc->call_calloc(memc, 1, sizeof(memcached_string_st));
  58
  59     if (string == NULL)
  60     {
  61       return NULL;
  62     }
  63
  64     string->options.is_allocated= true;
  65   }
  66   string->block_size= MEMCACHED_BLOCK_SIZE;
  67   string->root= memc;
  68
  69   rc=  _string_check(string, initial_size);
  70   if (rc != MEMCACHED_SUCCESS)
  71   {
  72     memc->call_free(memc, string);
  73     return NULL;
  74   }
  75
  76   string->options.is_initialized= true;
  77
  78   WATCHPOINT_ASSERT(string->string == string->end);
  79
  80   return string;
  81 }
  82
  83 memcached_return_t memcached_string_append_character(memcached_string_st *string,
  84                                                    char character)
  85 {
  86   memcached_return_t rc;
  87
  88   rc=  _string_check(string, 1);
  89
  90   if (rc != MEMCACHED_SUCCESS)
  91     return rc;
  92
  93   *string->end= character;
  94   string->end++;
  95
  96   return MEMCACHED_SUCCESS;
  97 }
  98
  99 memcached_return_t memcached_string_append(memcached_string_st *string,
 100                                          const char *value, size_t length)
 101 {
 102   memcached_return_t rc;
 103
 104   rc= _string_check(string, length);
 105
 106   if (rc != MEMCACHED_SUCCESS)
 107     return rc;
 108
 109   WATCHPOINT_ASSERT(length <= string->current_size);
 110   WATCHPOINT_ASSERT(string->string);
 111   WATCHPOINT_ASSERT(string->end >= string->string);
 112
 113   memcpy(string->end, value, length);
 114   string->end+= length;
 115
 116   return MEMCACHED_SUCCESS;
 117 }
 118
 119 char *memcached_string_c_copy(memcached_string_st *string)
 120 {
 121   char *c_ptr;
 122
 123   if (memcached_string_length(string) == 0)
 124     return NULL;
 125
 126   c_ptr= string->root->call_malloc(string->root, (memcached_string_length(string)+1) * sizeof(char));
 127
 128   if (c_ptr == NULL)
 129     return NULL;
 130
 131   memcpy(c_ptr, memcached_string_value(string), memcached_string_length(string));
 132   c_ptr[memcached_string_length(string)]= 0;
 133
 134   return c_ptr;
 135 }
 136
 137 memcached_return_t memcached_string_reset(memcached_string_st *string)
 138 {
 139   string->end= string->string;
 140
 141   return MEMCACHED_SUCCESS;
 142 }
 143
 144 void memcached_string_free(memcached_string_st *ptr)
 145 {
 146   if (ptr == NULL)
 147     return;
 148
 149   if (ptr->string)
 150   {
 151     ptr->root->call_free(ptr->root, ptr->string);
 152   }
 153
 154   if (memcached_is_allocated(ptr))
 155   {
 156     ptr->root->call_free(ptr->root, ptr);
 157   }
 158   else
 159   {
 160     ptr->options.is_initialized= false;
 161     memset(ptr, 0, sizeof(memcached_string_st));
 162   }
 163 }
 164
 165 memcached_return_t memcached_string_check(memcached_string_st *string, size_t need)
 166 {
 167   return _string_check(string, need);
 168 }
 169