git.m6w6.name Git - awesomized/libmemcached/blob - libmemcached/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  * Summary: String structure used for libmemcached.
   9  *
  10  */
  11
  12 #include "common.h"
  13
  14 inline static memcached_return_t _string_check(memcached_string_st *string, size_t need)
  15 {
  16   if (need && need > (size_t)(string->current_size - (size_t)(string->end - string->string)))
  17   {
  18     size_t current_offset= (size_t) (string->end - string->string);
  19     char *new_value;
  20     size_t adjust;
  21     size_t new_size;
  22
  23     /* This is the block multiplier. To keep it larger and surive division errors we must round it up */
  24     adjust= (need - (size_t)(string->current_size - (size_t)(string->end - string->string))) / MEMCACHED_BLOCK_SIZE;
  25     adjust++;
  26
  27     new_size= sizeof(char) * (size_t)((adjust * MEMCACHED_BLOCK_SIZE) + string->current_size);
  28     /* Test for overflow */
  29     if (new_size < need)
  30       return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
  31
  32     new_value= libmemcached_realloc(string->root, string->string, new_size);
  33
  34     if (new_value == NULL)
  35     {
  36       return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
  37     }
  38
  39     string->string= new_value;
  40     string->end= string->string + current_offset;
  41
  42     string->current_size+= (MEMCACHED_BLOCK_SIZE * adjust);
  43   }
  44
  45   return MEMCACHED_SUCCESS;
  46 }
  47
  48 static inline void _init_string(memcached_string_st *self)
  49 {
  50   self->current_size= 0;
  51   self->end= self->string= NULL;
  52 }
  53
  54 memcached_string_st *memcached_string_create(const memcached_st *memc, memcached_string_st *self, size_t initial_size)
  55 {
  56   memcached_return_t rc;
  57
  58   WATCHPOINT_ASSERT(memc);
  59
  60   /* Saving malloc calls :) */
  61   if (self)
  62   {
  63     WATCHPOINT_ASSERT(self->options.is_initialized == false);
  64
  65     self->options.is_allocated= false;
  66   }
  67   else
  68   {
  69     self= libmemcached_malloc(memc, sizeof(memcached_string_st));
  70
  71     if (self == NULL)
  72     {
  73       return NULL;
  74     }
  75
  76     self->options.is_allocated= true;
  77   }
  78   self->root= (memcached_st *)memc;
  79
  80   _init_string(self);
  81
  82   rc=  _string_check(self, initial_size);
  83   if (rc != MEMCACHED_SUCCESS)
  84   {
  85     if (rc == MEMCACHED_MEMORY_ALLOCATION_FAILURE)
  86     {
  87       memcached_set_errno(self->root, errno, NULL);
  88     }
  89     libmemcached_free(memc, self);
  90
  91     return NULL;
  92   }
  93
  94   self->options.is_initialized= true;
  95
  96   WATCHPOINT_ASSERT(self->string == self->end);
  97
  98   return self;
  99 }
 100
 101 memcached_return_t memcached_string_append_character(memcached_string_st *string,
 102                                                      char character)
 103 {
 104   memcached_return_t rc;
 105
 106   rc=  _string_check(string, 1);
 107
 108   if (rc != MEMCACHED_SUCCESS)
 109   {
 110     return rc;
 111   }
 112
 113   *string->end= character;
 114   string->end++;
 115
 116   return MEMCACHED_SUCCESS;
 117 }
 118
 119 memcached_return_t memcached_string_append(memcached_string_st *string,
 120                                            const char *value, size_t length)
 121 {
 122   memcached_return_t rc;
 123
 124   rc= _string_check(string, length);
 125
 126   if (rc != MEMCACHED_SUCCESS)
 127   {
 128     return rc;
 129   }
 130
 131   WATCHPOINT_ASSERT(length <= string->current_size);
 132   WATCHPOINT_ASSERT(string->string);
 133   WATCHPOINT_ASSERT(string->end >= string->string);
 134
 135   memcpy(string->end, value, length);
 136   string->end+= length;
 137
 138   return MEMCACHED_SUCCESS;
 139 }
 140
 141 char *memcached_string_c_copy(memcached_string_st *string)
 142 {
 143   char *c_ptr;
 144
 145   if (memcached_string_length(string) == 0)
 146     return NULL;
 147
 148   c_ptr= libmemcached_malloc(string->root, (memcached_string_length(string)+1) * sizeof(char));
 149
 150   if (c_ptr == NULL)
 151     return NULL;
 152
 153   memcpy(c_ptr, memcached_string_value(string), memcached_string_length(string));
 154   c_ptr[memcached_string_length(string)]= 0;
 155
 156   return c_ptr;
 157 }
 158
 159 memcached_return_t memcached_string_reset(memcached_string_st *string)
 160 {
 161   string->end= string->string;
 162
 163   return MEMCACHED_SUCCESS;
 164 }
 165
 166 void memcached_string_free(memcached_string_st *ptr)
 167 {
 168   if (ptr == NULL)
 169     return;
 170
 171   if (ptr->string)
 172   {
 173     libmemcached_free(ptr->root, ptr->string);
 174   }
 175
 176   if (memcached_is_allocated(ptr))
 177   {
 178     libmemcached_free(ptr->root, ptr);
 179   }
 180   else
 181   {
 182     ptr->options.is_initialized= false;
 183   }
 184 }
 185
 186 memcached_return_t memcached_string_check(memcached_string_st *string, size_t need)
 187 {
 188   return _string_check(string, need);
 189 }
 190
 191 size_t memcached_string_length(const memcached_string_st *self)
 192 {
 193   return (size_t)(self->end - self->string);
 194 }
 195
 196 size_t memcached_string_size(const memcached_string_st *self)
 197 {
 198   return self->current_size;
 199 }
 200
 201 const char *memcached_string_value(const memcached_string_st *self)
 202 {
 203   return self->string;
 204 }
 205
 206 char *memcached_string_value_mutable(const memcached_string_st *self)
 207 {
 208   return self->string;
 209 }
 210
 211 void memcached_string_set_length(memcached_string_st *self, size_t length)
 212 {
 213   self->end= self->string + length;
 214 }