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.
  14  *
  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
  27  *  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  28  *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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  30  *  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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  32  *  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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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
  47     /* This is the block multiplier. To keep it larger and surive division errors we must round it up */
  48     size_t adjust= (need - (size_t)(string->current_size - (size_t)(string->end - string->string))) / MEMCACHED_BLOCK_SIZE;
  49     adjust++;
  50
  51     size_t new_size= sizeof(char) * (size_t)((adjust * MEMCACHED_BLOCK_SIZE) + string->current_size);
  52     /* Test for overflow */
  53     if (new_size < need)
  54     {
  55       char error_message[1024];
  56       int error_message_length= snprintf(error_message, sizeof(error_message),"Needed %ld, got %ld", (long)need, (long)new_size);
  57       return memcached_set_error(*string->root, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT, error_message, error_message_length);
  58     }
  59
  60     char *new_value= libmemcached_xrealloc(string->root, string->string, new_size, char);
  61
  62     if (new_value == NULL)
  63     {
  64       return memcached_set_error(*string->root, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
  65     }
  66
  67     string->string= new_value;
  68     string->end= string->string + current_offset;
  69
  70     string->current_size+= (MEMCACHED_BLOCK_SIZE * adjust);
  71   }
  72
  73   return MEMCACHED_SUCCESS;
  74 }
  75
  76 static inline void _init_string(memcached_string_st *self)
  77 {
  78   self->current_size= 0;
  79   self->end= self->string= NULL;
  80 }
  81
  82 memcached_string_st *memcached_string_create(memcached_st *memc, memcached_string_st *self, size_t initial_size)
  83 {
  84   WATCHPOINT_ASSERT(memc);
  85
  86   /* Saving malloc calls :) */
  87   if (self)
  88   {
  89     WATCHPOINT_ASSERT(self->options.is_initialized == false);
  90
  91     memcached_set_allocated(self, false);
  92   }
  93   else
  94   {
  95     self= libmemcached_xmalloc(memc, memcached_string_st);
  96
  97     if (self == NULL)
  98     {
  99       return NULL;
 100     }
 101
 102     memcached_set_allocated(self, true);
 103   }
 104   self->root= memc;
 105
 106   _init_string(self);
 107
 108   if (memcached_failed(_string_check(self, initial_size)))
 109   {
 110     if (memcached_is_allocated(self))
 111     {
 112       libmemcached_free(memc, self);
 113     }
 114
 115     return NULL;
 116   }
 117
 118   self->options.is_initialized= true;
 119
 120   WATCHPOINT_ASSERT(self->string == self->end);
 121
 122   return self;
 123 }
 124
 125 static memcached_return_t memcached_string_append_null(memcached_string_st *string)
 126 {
 127   if (memcached_failed(_string_check(string, 1)))
 128   {
 129     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 130   }
 131
 132   *string->end= 0;
 133
 134   return MEMCACHED_SUCCESS;
 135 }
 136
 137 memcached_return_t memcached_string_append_character(memcached_string_st *string,
 138                                                      char character)
 139 {
 140   if (memcached_failed(_string_check(string, 1)))
 141   {
 142     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 143   }
 144
 145   *string->end= character;
 146   string->end++;
 147
 148   return MEMCACHED_SUCCESS;
 149 }
 150
 151 memcached_return_t memcached_string_append(memcached_string_st *string,
 152                                            const char *value, size_t length)
 153 {
 154   if (memcached_failed(_string_check(string, length)))
 155   {
 156     return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
 157   }
 158
 159   WATCHPOINT_ASSERT(length <= string->current_size);
 160   WATCHPOINT_ASSERT(string->string);
 161   WATCHPOINT_ASSERT(string->end >= string->string);
 162
 163   memcpy(string->end, value, length);
 164   string->end+= length;
 165
 166   return MEMCACHED_SUCCESS;
 167 }
 168
 169 char *memcached_string_c_copy(memcached_string_st *string)
 170 {
 171   if (not memcached_string_length(string))
 172     return NULL;
 173
 174   char *c_ptr= static_cast<char *>(libmemcached_malloc(string->root, (memcached_string_length(string)+1) * sizeof(char)));
 175
 176   if (not c_ptr)
 177     return NULL;
 178
 179   memcpy(c_ptr, memcached_string_value(string), memcached_string_length(string));
 180   c_ptr[memcached_string_length(string)]= 0;
 181
 182   return c_ptr;
 183 }
 184
 185 memcached_return_t memcached_string_reset(memcached_string_st *string)
 186 {
 187   string->end= string->string;
 188
 189   return MEMCACHED_SUCCESS;
 190 }
 191
 192 void memcached_string_free(memcached_string_st *ptr)
 193 {
 194   if (not ptr)
 195   {
 196     return;
 197   }
 198
 199   if (ptr->string)
 200   {
 201     libmemcached_free(ptr->root, ptr->string);
 202   }
 203
 204   if (memcached_is_allocated(ptr))
 205   {
 206     libmemcached_free(ptr->root, ptr);
 207   }
 208   else
 209   {
 210     ptr->options.is_initialized= false;
 211   }
 212 }
 213
 214 memcached_return_t memcached_string_check(memcached_string_st *string, size_t need)
 215 {
 216   return _string_check(string, need);
 217 }
 218
 219 size_t memcached_string_length(const memcached_string_st *self)
 220 {
 221   return size_t(self->end -self->string);
 222 }
 223
 224 size_t memcached_string_size(const memcached_string_st *self)
 225 {
 226   return self->current_size;
 227 }
 228
 229 const char *memcached_string_value(const memcached_string_st *self)
 230 {
 231   return self->string;
 232 }
 233
 234 char *memcached_string_take_value(memcached_string_st *self)
 235 {
 236   assert_msg(self, "Invalid memcached_string_st");
 237   // If we fail at adding the null, we copy and move on
 238   if (memcached_success(memcached_string_append_null(self)))
 239   {
 240     return memcached_string_c_copy(self);
 241   }
 242
 243   char *value= self->string;
 244
 245   _init_string(self);
 246
 247   return value;
 248 }
 249
 250 char *memcached_string_value_mutable(const memcached_string_st *self)
 251 {
 252   return self->string;
 253 }
 254
 255 void memcached_string_set_length(memcached_string_st *self, size_t length)
 256 {
 257   self->end= self->string + length;
 258 }