First version of replication.

[awesomized/libmemcached] / lib / memcached_auto.c

diff --git a/lib/memcached_auto.c b/lib/memcached_auto.c
index aa7ce5dfcddfd87de212be53e8c447d1818c3f20..1f61a18ce0fe05c318fee3d0f7ebafa469f65eca 100644 (file)
--- a/lib/memcached_auto.c
+++ b/lib/memcached_auto.c
@@ -1,22 +1,27 @@
-#include <memcached.h>
+#include "common.h"
 
 static memcached_return memcached_auto(memcached_st *ptr, 
                                        char *verb,
                                        char *key, size_t key_length,
                                        unsigned int offset,
-                                       unsigned int *value)
+                                       uint64_t *value)
 {
-  size_t send_length, sent_length;
-  memcached_return rc;
+  size_t send_length;
   char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
   unsigned int server_key;
+  uint8_t replicas= 0;
+  memcached_return rc[MEMCACHED_MAX_REPLICAS];
+
+  if (key_length == 0)
+    return MEMCACHED_NO_KEY_PROVIDED;
 
-  rc= memcached_connect(ptr);
+  if (ptr->hosts == NULL || ptr->number_of_hosts == 0)
+    return MEMCACHED_NO_SERVERS;
 
-  if (rc != MEMCACHED_SUCCESS)
-    return rc;
+  if ((ptr->flags & MEM_VERIFY_KEY) && (memcachd_key_test(&key, &key_length, 1) == MEMCACHED_BAD_KEY_PROVIDED))
+    return MEMCACHED_BAD_KEY_PROVIDED;
 
-  server_key= memcached_generate_hash(key, key_length) % ptr->number_of_hosts;
+  server_key= memcached_generate_hash(ptr, key, key_length);
 
   send_length= snprintf(buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, 
                         "%s %.*s %u\r\n", verb, 
@@ -24,45 +29,82 @@ static memcached_return memcached_auto(memcached_st *ptr,
                         offset);
   if (send_length >= MEMCACHED_DEFAULT_COMMAND_SIZE)
     return MEMCACHED_WRITE_FAILURE;
-  sent_length= send(ptr->hosts[server_key].fd, buffer, send_length, 0);
 
-  if (sent_length == -1 || sent_length != send_length)
-    return MEMCACHED_WRITE_FAILURE;
+  do 
+  {
+    rc[replicas]= memcached_do(&ptr->hosts[server_key], buffer, send_length, 1);
+    if (rc[replicas] != MEMCACHED_SUCCESS)
+      goto error;
 
-  memset(buffer, 0, MEMCACHED_DEFAULT_COMMAND_SIZE);
-  send_length= read(ptr->hosts[server_key].fd, buffer, MEMCACHED_DEFAULT_COMMAND_SIZE);
+    rc[replicas]= memcached_response(&ptr->hosts[server_key], buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, NULL);
 
-  if (!memcmp(buffer, "ERROR\r\n", MEMCACHED_DEFAULT_COMMAND_SIZE))
-  {
-    *value= 0;
-    rc= MEMCACHED_PROTOCOL_ERROR;
-  }
-  else if (!memcmp(buffer, "NOT_FOUND\r\n", MEMCACHED_DEFAULT_COMMAND_SIZE))
-  {
-    *value= 0;
-    rc= MEMCACHED_NOTFOUND;
-  }
-  else
+    /* 
+      So why recheck responce? Because the protocol is brain dead :)
+      The number returned might end up equaling one of the string 
+      values. Less chance of a mistake with strncmp() so we will 
+      use it. We still called memcached_response() though since it
+      worked its magic for non-blocking IO.
+    */
+    if (!strncmp(buffer, "ERROR\r\n", 7))
+    {
+      *value= 0;
+      rc[replicas]= MEMCACHED_PROTOCOL_ERROR;
+    }
+    else if (!strncmp(buffer, "NOT_FOUND\r\n", 11))
+    {
+      *value= 0;
+      rc[replicas]= MEMCACHED_NOTFOUND;
+    }
+    else
+    {
+      *value= (uint64_t)strtoll(buffer, (char **)NULL, 10);
+      rc[replicas]= MEMCACHED_SUCCESS;
+    }
+    /* On error we just jump to the next potential server */
+error:
+    if (replicas > 1 && ptr->distribution == MEMCACHED_DISTRIBUTION_CONSISTENT)
+    {
+      if (server_key == (ptr->number_of_hosts - 1))
+        server_key= 0;
+      else
+        server_key++;
+    }
+  } while ((++replicas) < ptr->number_of_replicas);
+
+  /* As long as one object gets stored, we count this as a success */
+  while (replicas--)
   {
-    *value= strtol(buffer, (char **)NULL, 10);
-    rc= MEMCACHED_SUCCESS;
+    if (rc[replicas] == MEMCACHED_STORED)
+      return MEMCACHED_SUCCESS;
   }
 
-  return rc;
+  return rc[0];
 }
 
 memcached_return memcached_increment(memcached_st *ptr, 
                                      char *key, size_t key_length,
-                                     unsigned int offset,
-                                     unsigned int *value)
+                                     uint32_t offset,
+                                     uint64_t *value)
 {
-  return memcached_auto(ptr, "incr", key, key_length, offset, value);
+  memcached_return rc;
+
+  LIBMEMCACHED_MEMCACHED_INCREMENT_START();
+  rc= memcached_auto(ptr, "incr", key, key_length, offset, value);
+  LIBMEMCACHED_MEMCACHED_INCREMENT_END();
+
+  return rc;
 }
 
 memcached_return memcached_decrement(memcached_st *ptr, 
                                      char *key, size_t key_length,
-                                     unsigned int offset,
-                                     unsigned int *value)
+                                     uint32_t offset,
+                                     uint64_t *value)
 {
-  return memcached_auto(ptr, "decr", key, key_length, offset, value);
+  memcached_return rc;
+
+  LIBMEMCACHED_MEMCACHED_DECREMENT_START();
+  rc= memcached_auto(ptr, "decr", key, key_length, offset, value);
+  LIBMEMCACHED_MEMCACHED_DECREMENT_END();
+
+  return rc;
 }