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

   1 #include "common.h"
   2 #include "memcached_io.h"
   3
   4 static char *memcached_value_fetch(memcached_st *ptr, char *key, size_t *key_length,
   5                                    size_t *value_length,
   6                                    uint16_t *flags,
   7                                    memcached_return *error,
   8                                    char load_key,
   9                                    unsigned int server_key)
  10 {
  11   char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
  12   char *string_ptr;
  13   char *end_ptr;
  14
  15   memset(buffer, 0, MEMCACHED_DEFAULT_COMMAND_SIZE);
  16   end_ptr= buffer + MEMCACHED_DEFAULT_COMMAND_SIZE;
  17
  18   *value_length= 0;
  19   *flags= 0;
  20
  21   *error= memcached_response(ptr, buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, server_key);
  22
  23   if (*error == MEMCACHED_SUCCESS)
  24   {
  25     char *next_ptr;
  26
  27     string_ptr= buffer;
  28     string_ptr+= 6; /* "VALUE " */
  29
  30     /* We load the key */
  31     if (load_key)
  32     {
  33       memset(key, 0, MEMCACHED_MAX_KEY);
  34       *key_length= 0;
  35
  36       for (; end_ptr > string_ptr && *string_ptr != ' '; string_ptr++)
  37       {
  38         *key= *string_ptr;
  39         key++;
  40         (*key_length)++;
  41       }
  42     }
  43     else /* Skip characters */
  44       for (; end_ptr > string_ptr && *string_ptr != ' '; string_ptr++);
  45
  46     if (end_ptr == string_ptr)
  47         goto read_error;
  48
  49     /* Flags fetch move past space */
  50     string_ptr++;
  51     if (end_ptr == string_ptr)
  52         goto read_error;
  53     for (next_ptr= string_ptr; end_ptr > string_ptr && *string_ptr != ' '; string_ptr++);
  54     *flags= (uint16_t)strtol(next_ptr, &string_ptr, 10);
  55
  56     if (end_ptr == string_ptr)
  57         goto read_error;
  58
  59     /* Length fetch move past space*/
  60     string_ptr++;
  61     if (end_ptr == string_ptr)
  62         goto read_error;
  63
  64     for (next_ptr= string_ptr; end_ptr > string_ptr && *string_ptr != ' '; string_ptr++);
  65     *value_length= (size_t)strtoll(next_ptr, &string_ptr, 10);
  66
  67     if (end_ptr == string_ptr)
  68         goto read_error;
  69
  70     /* Skip past the \r\n */
  71     string_ptr+= 2;
  72
  73     if (end_ptr < string_ptr)
  74         goto read_error;
  75
  76     if (*value_length)
  77     {
  78       size_t read_length;
  79       size_t to_read;
  80       char *value;
  81       char *value_ptr;
  82
  83       /* We add two bytes so that we can walk the \r\n */
  84       value= (char *)malloc(((*value_length) +2) * sizeof(char));
  85       if (!value)
  86       {
  87         *value_length= 0;
  88         *error= MEMCACHED_MEMORY_ALLOCATION_FAILURE;
  89         return NULL;
  90       }
  91       memset(value, 0, ((*value_length) +2) * sizeof(char));
  92
  93       value_ptr= value;
  94       read_length= 0;
  95       /*
  96         We read the \r\n into the string since not doing so is more
  97         cycles then the waster of memory to do so.
  98
  99         We are null terminating through, which will most likely make
 100         some people lazy about using the return length.
 101       */
 102       to_read= (*value_length) + 2;
 103
 104       read_length= memcached_io_read(ptr, server_key,
 105                                      value_ptr, to_read);
 106
 107       if (read_length != (size_t)(*value_length + 2))
 108       {
 109         free(value);
 110         goto read_error;
 111       }
 112
 113       value[*value_length]= 0;
 114       value[(*value_length) + 1]= 0;
 115
 116       return value;
 117     }
 118   }
 119   else if (*error == MEMCACHED_END)
 120     *error= MEMCACHED_NOTFOUND;
 121
 122   return NULL;
 123 read_error:
 124   *error= MEMCACHED_PARTIAL_READ;
 125   return NULL;
 126 }
 127
 128 /*
 129   What happens if no servers exist?
 130 */
 131 char *memcached_get(memcached_st *ptr, char *key, size_t key_length,
 132                     size_t *value_length,
 133                     uint16_t *flags,
 134                     memcached_return *error)
 135 {
 136   char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
 137   char *buf_ptr= buffer;
 138   unsigned int server_key;
 139   char *value= NULL;
 140   LIBMEMCACHED_MEMCACHED_GET_START();
 141
 142   server_key= memcached_generate_hash(ptr, key, key_length);
 143
 144   *value_length= 0;
 145   *error= memcached_connect(ptr, server_key);
 146
 147   if (*error != MEMCACHED_SUCCESS)
 148     goto error;
 149
 150   memcpy(buf_ptr, "get ", 4);
 151   buf_ptr+= 4;
 152   memcpy(buf_ptr, key, key_length);
 153   buf_ptr+= key_length;
 154   memcpy(buf_ptr, "\r\n", 2);
 155   buf_ptr+= 2;
 156
 157   if ((memcached_io_write(ptr, server_key, buffer, (size_t)(buf_ptr - buffer), 1)) == -1)
 158   {
 159     *error= MEMCACHED_WRITE_FAILURE;
 160     goto error;
 161   }
 162
 163   value= memcached_value_fetch(ptr, key, &key_length, value_length, flags,
 164                                error, 0, server_key);
 165   if (*error == MEMCACHED_END && *value_length == 0)
 166   {
 167     *error= MEMCACHED_NOTFOUND;
 168     goto error;
 169   }
 170   else if (*error == MEMCACHED_END)
 171     assert(0); /* If this happens we have somehow messed up the fetch */
 172   else if (*error == MEMCACHED_SUCCESS)
 173   {
 174     memcached_return rc;
 175     /* We need to read END */
 176     rc= memcached_response(ptr, buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, server_key);
 177
 178     if (rc != MEMCACHED_END)
 179     {
 180       *error= MEMCACHED_PROTOCOL_ERROR;
 181       goto error;
 182     }
 183   }
 184   else
 185       goto error;
 186
 187   LIBMEMCACHED_MEMCACHED_GET_END();
 188
 189   return value;
 190
 191 error:
 192   free(value);
 193   *value_length= 0;
 194
 195   LIBMEMCACHED_MEMCACHED_GET_END();
 196
 197     return NULL;
 198 }
 199
 200 memcached_return memcached_mget(memcached_st *ptr,
 201                                 char **keys, size_t *key_length,
 202                                 unsigned int number_of_keys)
 203 {
 204   unsigned int x;
 205   memcached_return rc= MEMCACHED_NOTFOUND;
 206   char *cursor_key_exec;
 207   LIBMEMCACHED_MEMCACHED_MGET_START();
 208   ptr->cursor_server= 0;
 209
 210   if (number_of_keys == 0)
 211     return MEMCACHED_NOTFOUND;
 212
 213   cursor_key_exec= (char *)malloc(sizeof(char) * ptr->number_of_hosts);
 214   memset(cursor_key_exec, 0, sizeof(char) * ptr->number_of_hosts);
 215
 216   for (x= 0; x < number_of_keys; x++)
 217   {
 218     unsigned int server_key;
 219
 220     server_key= memcached_generate_hash(ptr, keys[x], key_length[x]);
 221
 222     if (cursor_key_exec[server_key] == 0)
 223     {
 224       rc= memcached_connect(ptr, server_key);
 225
 226       if ((memcached_io_write(ptr, server_key, "get ", 4, 0)) == -1)
 227       {
 228         memcached_quit(ptr);
 229         rc= MEMCACHED_SOME_ERRORS;
 230         break;
 231       }
 232     }
 233
 234     if ((memcached_io_write(ptr, server_key, keys[x], key_length[x], 0)) == -1)
 235     {
 236       memcached_quit(ptr);
 237       rc= MEMCACHED_SOME_ERRORS;
 238       break;
 239     }
 240
 241     if ((memcached_io_write(ptr, server_key, " ", 1, 0)) == -1)
 242     {
 243       memcached_quit(ptr);
 244       rc= MEMCACHED_SOME_ERRORS;
 245       break;
 246     }
 247     cursor_key_exec[server_key]= 1;
 248   }
 249
 250
 251   /*
 252     Should we muddle on if some servers are dead?
 253   */
 254   for (x= 0; x < ptr->number_of_hosts; x++)
 255   {
 256     if (cursor_key_exec[x])
 257     {
 258       /* We need to doo something about non-connnected hosts in the future */
 259       if ((memcached_io_write(ptr, x, "\r\n", 2, 1)) == -1)
 260       {
 261         memcached_quit(ptr);
 262         rc= MEMCACHED_SOME_ERRORS;
 263         break;
 264       }
 265
 266       ptr->hosts[x].cursor_active= 1;
 267     }
 268     else
 269       ptr->hosts[x].cursor_active= 0;
 270   }
 271
 272   free(cursor_key_exec);
 273
 274   LIBMEMCACHED_MEMCACHED_MGET_END();
 275   return rc;
 276 }
 277
 278 char *memcached_fetch(memcached_st *ptr, char *key, size_t *key_length,
 279                     size_t *value_length,
 280                     uint16_t *flags,
 281                     memcached_return *error)
 282 {
 283   char *value_check;
 284
 285   while (ptr->cursor_server < ptr->number_of_hosts)
 286   {
 287     if (!ptr->hosts[ptr->cursor_server].cursor_active)
 288     {
 289       ptr->cursor_server++;
 290       continue;
 291     }
 292
 293     value_check= memcached_value_fetch(ptr, key, key_length, value_length, flags,
 294                                        error, 1, ptr->cursor_server);
 295
 296     if (*error == MEMCACHED_NOTFOUND)
 297       ptr->cursor_server++;
 298     else if (*error == MEMCACHED_END && *value_length == 0)
 299       return NULL;
 300     else if (*error == MEMCACHED_END)
 301       assert(0); /* If this happens we have somehow messed up the fetch */
 302     else if (*error != MEMCACHED_SUCCESS)
 303       return NULL;
 304     else
 305       return value_check;
 306
 307   }
 308
 309   *value_length= 0;
 310   return NULL;
 311 }