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, memcached_string_st *string, size_t initial_size)
  40 {
  41   memcached_return rc;
  42
  43   /* Saving malloc calls :) */
  44   if (string)
  45   {
  46     memset(string, 0, sizeof(memcached_string_st));
  47     string->is_allocated= MEMCACHED_NOT_ALLOCATED;
  48   }
  49   else
  50   {
  51     string= (memcached_string_st *)malloc(sizeof(memcached_string_st));
  52     if (!string)
  53       return NULL;
  54     memset(string, 0, sizeof(memcached_string_st));
  55     string->is_allocated= MEMCACHED_ALLOCATED;
  56   }
  57   string->end= string->string;
  58   string->block_size= initial_size;
  59
  60   rc=  memcached_string_check(string, initial_size);
  61   if (rc != MEMCACHED_SUCCESS)
  62   {
  63     free(string);
  64     return NULL;
  65   }
  66
  67   WATCHPOINT_ASSERT(string->string == string->end);
  68
  69   return string;
  70 }
  71
  72 memcached_return memcached_string_append_character(memcached_st *ptr,
  73                                                    memcached_string_st *string,
  74                                                    char character)
  75 {
  76   memcached_return rc;
  77
  78   rc=  memcached_string_check(string, 1);
  79
  80   if (rc != MEMCACHED_SUCCESS)
  81     return rc;
  82
  83   *string->end= ' ';
  84   string->end++;
  85
  86   return MEMCACHED_SUCCESS;
  87 }
  88
  89 memcached_return memcached_string_append(memcached_st *ptr, memcached_string_st *string,
  90                                          char *value, size_t length)
  91 {
  92   memcached_return rc;
  93
  94   rc= memcached_string_check(string, length);
  95
  96   if (rc != MEMCACHED_SUCCESS)
  97     return rc;
  98
  99   WATCHPOINT_ASSERT(length <= string->current_size);
 100   WATCHPOINT_ASSERT(string->string);
 101   WATCHPOINT_ASSERT(string->end >= string->string);
 102
 103   memcpy(string->end, value, length);
 104   string->end+= length;
 105
 106   return MEMCACHED_SUCCESS;
 107 }
 108
 109 size_t memcached_string_backspace(memcached_st *ptr, memcached_string_st *string, size_t remove)
 110 {
 111   if (string->end - string->string  > remove)
 112   {
 113     size_t difference;
 114
 115     difference= string->end - string->string;
 116     string->end= string->string;
 117
 118     return difference;
 119   }
 120   string->end-= remove;
 121
 122   return remove;
 123 }
 124
 125 memcached_return memcached_string_reset(memcached_st *ptr, memcached_string_st *string)
 126 {
 127   string->end= string->string;
 128
 129   return MEMCACHED_SUCCESS;
 130 }
 131
 132 void memcached_string_free(memcached_st *ptr, memcached_string_st *string)
 133 {
 134   free(string->string);
 135   if (string->is_allocated == MEMCACHED_ALLOCATED)
 136     free(string);
 137 }