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

   1 #include "common.h"
   2
   3 memcached_return memcached_string_check(memcached_string_st *string, size_t need)
   4 {
   5   if (need > (size_t)(string->current_size - (size_t)(string->end - string->string)))
   6   {
   7     size_t current_offset= string->end - string->string;
   8     char *new_value;
   9     size_t adjust;
  10     size_t new_size;
  11
  12     /* This is the block multiplier. To keep it larger and surive division errors we must round it up */
  13     adjust= (need - (size_t)(string->current_size - (size_t)(string->end - string->string))) / string->block_size;
  14     adjust++;
  15
  16     new_size= sizeof(char) * (size_t)((adjust * string->block_size) + string->current_size);
  17     /* Test for overflow */
  18     if (new_size < need)
  19       return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
  20
  21     new_value= (char *)realloc(string->string, new_size);
  22
  23     if (new_value == NULL)
  24       return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
  25
  26     string->string= new_value;
  27     string->end= string->string + current_offset;
  28
  29     string->current_size+= (string->block_size * adjust);
  30
  31     /* We zero the block structure we just realloced */
  32     memset((string->string + current_offset), 0,
  33            sizeof(char) * string->block_size);
  34   }
  35
  36   return MEMCACHED_SUCCESS;
  37 }
  38
  39 memcached_string_st *memcached_string_create(memcached_st *ptr, size_t initial_size)
  40 {
  41   memcached_return rc;
  42   memcached_string_st *string;
  43
  44   /* Saving malloc calls :) */
  45   string= (memcached_string_st *)malloc(sizeof(memcached_string_st));
  46   if (!string)
  47     return NULL;
  48   string->end= string->string;
  49   memset(string, 0, sizeof(memcached_string_st));
  50   string->block_size= initial_size;
  51
  52   rc=  memcached_string_check(string, initial_size);
  53   if (rc != MEMCACHED_SUCCESS)
  54   {
  55     free(string);
  56     return NULL;
  57   }
  58
  59   WATCHPOINT_ASSERT(string->string == string->end);
  60
  61   return string;
  62 }
  63
  64 memcached_return memcached_string_append_character(memcached_st *ptr,
  65                                                    memcached_string_st *string,
  66                                                    char character)
  67 {
  68   memcached_return rc;
  69
  70   rc=  memcached_string_check(string, 1);
  71
  72   if (rc != MEMCACHED_SUCCESS)
  73     return rc;
  74
  75   *string->end= ' ';
  76   string->end++;
  77
  78   return MEMCACHED_SUCCESS;
  79 }
  80
  81 memcached_return memcached_string_append(memcached_st *ptr, memcached_string_st *string,
  82                                          char *value, size_t length)
  83 {
  84   memcached_return rc;
  85
  86   rc= memcached_string_check(string, length);
  87
  88   if (rc != MEMCACHED_SUCCESS)
  89     return rc;
  90
  91   WATCHPOINT_ASSERT(length <= string->current_size);
  92   WATCHPOINT_ASSERT(string->string);
  93   WATCHPOINT_ASSERT(string->end >= string->string);
  94
  95   memcpy(string->end, value, length);
  96   string->end+= length;
  97
  98   return MEMCACHED_SUCCESS;
  99 }
 100
 101 size_t memcached_string_backspace(memcached_st *ptr, memcached_string_st *string, size_t remove)
 102 {
 103   if (string->end - string->string  > remove)
 104   {
 105     size_t difference;
 106
 107     difference= string->end - string->string;
 108     string->end= string->string;
 109
 110     return difference;
 111   }
 112   string->end-= remove;
 113
 114   return remove;
 115 }
 116
 117 memcached_return memcached_string_reset(memcached_st *ptr, memcached_string_st *string)
 118 {
 119   string->end= string->string;
 120
 121   return MEMCACHED_SUCCESS;
 122 }
 123
 124 void memcached_string_free(memcached_st *ptr, memcached_string_st *string)
 125 {
 126   free(string->string);
 127   free(string);
 128 }