git.m6w6.name Git - awesomized/libmemcached/blob - libmemcached/string.cc

   1 /*  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
   2  *
   3  *  Libmemcached library
   4  *
   5  *  Copyright (C) 2011 Data Differential, http://datadifferential.com/
   6  *  Copyright (C) 2006-2009 Brian Aker All rights reserved.
   7  *
   8  *  Redistribution and use in source and binary forms, with or without
   9  *  modification, are permitted provided that the following conditions are
  10  *  met:
  11  *
  12  *      * Redistributions of source code must retain the above copyright
  13  *  notice, this list of conditions and the following disclaimer.
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  15  *      * Redistributions in binary form must reproduce the above
  16  *  copyright notice, this list of conditions and the following disclaimer
  17  *  in the documentation and/or other materials provided with the
  18  *  distribution.
  19  *
  20  *      * The names of its contributors may not be used to endorse or
  21  *  promote products derived from this software without specific prior
  22  *  written permission.
  23  *
  24  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  25  *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  26  *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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  28  *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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  34  *  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  *
  36  */
  37
  38
  39 #include <libmemcached/common.h>
  40
  41 inline static memcached_return_t _string_check(memcached_string_st *string, size_t need)
  42 {
  43   if (need && need > (size_t)(string->current_size - (size_t)(string->end - string->string)))
  44   {
  45     size_t current_offset= (size_t) (string->end - string->string);
  46     size_t adjust;
  47     size_t new_size;
  48
  49     /* This is the block multiplier. To keep it larger and surive division errors we must round it up */
  50     adjust= (need - (size_t)(string->current_size - (size_t)(string->end - string->string))) / MEMCACHED_BLOCK_SIZE;
  51     adjust++;
  52
  53     new_size= sizeof(char) * (size_t)((adjust * MEMCACHED_BLOCK_SIZE) + string->current_size);
  54     /* Test for overflow */
  55     if (new_size < need)
  56       return memcached_set_error(*string->root, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
  57
  58     char *new_value= libmemcached_xrealloc(string->root, string->string, new_size, char);
  59
  60     if (new_value == NULL)
  61     {
  62       return memcached_set_error(*string->root, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
  63     }
  64
  65     string->string= new_value;
  66     string->end= string->string + current_offset;
  67
  68     string->current_size+= (MEMCACHED_BLOCK_SIZE * adjust);
  69   }
  70
  71   return MEMCACHED_SUCCESS;
  72 }
  73
  74 static inline void _init_string(memcached_string_st *self)
  75 {
  76   self->current_size= 0;
  77   self->end= self->string= NULL;
  78 }
  79
  80 memcached_string_st *memcached_string_create(memcached_st *memc, memcached_string_st *self, size_t initial_size)
  81 {
  82   WATCHPOINT_ASSERT(memc);
  83
  84   /* Saving malloc calls :) */
  85   if (self)
  86   {
  87     WATCHPOINT_ASSERT(self->options.is_initialized == false);
  88
  89     memcached_set_allocated(self, false);
  90   }
  91   else
  92   {
  93     self= libmemcached_xmalloc(memc, memcached_string_st);
  94
  95     if (self == NULL)
  96     {
  97       return NULL;
  98     }
  99
 100     memcached_set_allocated(self, true);
 101   }
 102   self->root= memc;
 103
 104   _init_string(self);
 105
 106   if (memcached_failed(_string_check(self, initial_size)))
 107   {
 108     if (memcached_is_allocated(self))
 109     {
 110       libmemcached_free(memc, self);
 111     }
 112
 113     return NULL;
 114   }
 115
 116   self->options.is_initialized= true;
 117
 118   WATCHPOINT_ASSERT(self->string == self->end);
 119
 120   return self;
 121 }
 122
 123 static memcached_return_t memcached_string_append_null(memcached_string_st *string)
 124 {
 125   if (memcached_failed(_string_check(string, 1)))
 126   {
 127     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 128   }
 129
 130   *string->end= 0;
 131
 132   return MEMCACHED_SUCCESS;
 133 }
 134
 135 memcached_return_t memcached_string_append_character(memcached_string_st *string,
 136                                                      char character)
 137 {
 138   if (memcached_failed(_string_check(string, 1)))
 139   {
 140     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 141   }
 142
 143   *string->end= character;
 144   string->end++;
 145
 146   return MEMCACHED_SUCCESS;
 147 }
 148
 149 memcached_return_t memcached_string_append(memcached_string_st *string,
 150                                            const char *value, size_t length)
 151 {
 152   if (memcached_failed(_string_check(string, length)))
 153   {
 154     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 155   }
 156
 157   WATCHPOINT_ASSERT(length <= string->current_size);
 158   WATCHPOINT_ASSERT(string->string);
 159   WATCHPOINT_ASSERT(string->end >= string->string);
 160
 161   memcpy(string->end, value, length);
 162   string->end+= length;
 163
 164   return MEMCACHED_SUCCESS;
 165 }
 166
 167 char *memcached_string_c_copy(memcached_string_st *string)
 168 {
 169   if (not memcached_string_length(string))
 170     return NULL;
 171
 172   char *c_ptr= static_cast<char *>(libmemcached_malloc(string->root, (memcached_string_length(string)+1) * sizeof(char)));
 173
 174   if (not c_ptr)
 175     return NULL;
 176
 177   memcpy(c_ptr, memcached_string_value(string), memcached_string_length(string));
 178   c_ptr[memcached_string_length(string)]= 0;
 179
 180   return c_ptr;
 181 }
 182
 183 memcached_return_t memcached_string_reset(memcached_string_st *string)
 184 {
 185   string->end= string->string;
 186
 187   return MEMCACHED_SUCCESS;
 188 }
 189
 190 void memcached_string_free(memcached_string_st *ptr)
 191 {
 192   if (not ptr)
 193   {
 194     return;
 195   }
 196
 197   if (ptr->string)
 198   {
 199     libmemcached_free(ptr->root, ptr->string);
 200   }
 201
 202   if (memcached_is_allocated(ptr))
 203   {
 204     libmemcached_free(ptr->root, ptr);
 205   }
 206   else
 207   {
 208     ptr->options.is_initialized= false;
 209   }
 210 }
 211
 212 memcached_return_t memcached_string_check(memcached_string_st *string, size_t need)
 213 {
 214   return _string_check(string, need);
 215 }
 216
 217 size_t memcached_string_length(const memcached_string_st *self)
 218 {
 219   return size_t(self->end -self->string);
 220 }
 221
 222 size_t memcached_string_size(const memcached_string_st *self)
 223 {
 224   return self->current_size;
 225 }
 226
 227 const char *memcached_string_value(const memcached_string_st *self)
 228 {
 229   return self->string;
 230 }
 231
 232 char *memcached_string_take_value(memcached_string_st *self)
 233 {
 234   assert_msg(self, "Invalid memcached_string_st");
 235   // If we fail at adding the null, we copy and move on
 236   if (memcached_success(memcached_string_append_null(self)))
 237   {
 238     return memcached_string_c_copy(self);
 239   }
 240
 241   char *value= self->string;
 242
 243   _init_string(self);
 244
 245   return value;
 246 }
 247
 248 char *memcached_string_value_mutable(const memcached_string_st *self)
 249 {
 250   return self->string;
 251 }
 252
 253 void memcached_string_set_length(memcached_string_st *self, size_t length)
 254 {
 255   self->end= self->string + length;
 256 }