memcached_return_t memcached_response(memcached_server_write_instance_st ptr,
char *buffer, size_t buffer_length,
memcached_result_st *result)
{
/* We may have old commands in the buffer not set, first purge */
if ((ptr->root->flags.no_block) && (memcached_is_processing_input(ptr->root) == false))
{
(void)memcached_io_write(ptr, NULL, 0, true);
}
/*
* The previous implementation purged all pending requests and just
* returned the last one. Purge all pending messages to ensure backwards
* compatibility. But this breaks prefetching, so we only make it when
* mget_flush_old_results is true.
*/
if ((ptr->root->flags.mget_flush_old_results) && (ptr->root->flags.binary_protocol == false))
while (memcached_server_response_count(ptr) > 1)
{
memcached_return_t rc= memcached_read_one_response(ptr, buffer, buffer_length, result);
unlikely (rc != MEMCACHED_END &&
rc != MEMCACHED_STORED &&
rc != MEMCACHED_SUCCESS &&
rc != MEMCACHED_STAT &&
rc != MEMCACHED_DELETED &&
rc != MEMCACHED_NOTFOUND &&
rc != MEMCACHED_NOTSTORED &&
rc != MEMCACHED_DATA_EXISTS)
return rc;
}
return memcached_read_one_response(ptr, buffer, buffer_length, result);
}
char *memcached_fetch(memcached_st *ptr, char *key, size_t *key_length,
size_t *value_length,
uint32_t *flags,
memcached_return *error)
{
memcached_result_st *result_buffer= &ptr->result;
while (ptr->cursor_server < ptr->number_of_hosts)
{
char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
if (memcached_server_response_count(&ptr->hosts[ptr->cursor_server]) == 0)
{
ptr->cursor_server++;
continue;
}
*error= memcached_response(&ptr->hosts[ptr->cursor_server], buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, result_buffer);
if (*error == MEMCACHED_END) /* END means that we move on to the next */
{
memcached_server_response_reset(&ptr->hosts[ptr->cursor_server]);
ptr->cursor_server++;
continue;
}
else if (*error == MEMCACHED_SUCCESS)
{
*value_length= memcached_string_length(&result_buffer->value);
if (key)
{
strncpy(key, result_buffer->key, result_buffer->key_length);
*key_length= result_buffer->key_length;
}
if (result_buffer->flags)
*flags= result_buffer->flags;
else
*flags= 0;
return memcached_string_c_copy(&result_buffer->value);
}
else
{
*value_length= 0;
return NULL;
}
}
ptr->cursor_server= 0;
*value_length= 0;
return NULL;
}
memcached_result_st *memcached_fetch_result(memcached_st *ptr,
memcached_result_st *result,
memcached_return *error)
{
if (result == NULL)
result= memcached_result_create(ptr, NULL);
#ifdef UNUSED
if (ptr->flags & MEM_NO_BLOCK)
memcached_io_preread(ptr);
#endif
while (ptr->cursor_server < ptr->number_of_hosts)
{
char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
if (memcached_server_response_count(&ptr->hosts[ptr->cursor_server]) == 0)
{
ptr->cursor_server++;
continue;
}
*error= memcached_response(&ptr->hosts[ptr->cursor_server], buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, result);
if (*error == MEMCACHED_END) /* END means that we move on to the next */
{
memcached_server_response_reset(&ptr->hosts[ptr->cursor_server]);
ptr->cursor_server++;
continue;
}
else if (*error == MEMCACHED_SUCCESS)
return result;
else
return NULL;
}
/* We have completed reading data */
if (result->is_allocated)
memcached_result_free(result);
else
memcached_string_reset(&result->value);
ptr->cursor_server= 0;
return NULL;
}
void memcached_io_preread(memcached_st *ptr)
{
unsigned int x;
return;
for (x= 0; x < ptr->number_of_hosts; x++)
{
if (memcached_server_response_count(ptr, x) &&
ptr->hosts[x].read_data_length < MEMCACHED_MAX_BUFFER )
{
size_t data_read;
data_read= read(ptr->hosts[x].fd,
ptr->hosts[x].read_ptr + ptr->hosts[x].read_data_length,
MEMCACHED_MAX_BUFFER - ptr->hosts[x].read_data_length);
if (data_read == -1)
continue;
ptr->hosts[x].read_buffer_length+= data_read;
ptr->hosts[x].read_data_length+= data_read;
}
}
}
memcached_return_t memcached_purge(memcached_server_write_instance_st ptr)
{
uint32_t x;
memcached_return_t ret= MEMCACHED_SUCCESS;
memcached_st *root= (memcached_st *)ptr->root;
uint32_t no_msg;
if (memcached_is_purging(ptr->root) || /* already purging */
(memcached_server_response_count(ptr) < ptr->root->io_msg_watermark &&
ptr->io_bytes_sent < ptr->root->io_bytes_watermark) ||
(ptr->io_bytes_sent >= ptr->root->io_bytes_watermark &&
memcached_server_response_count(ptr) < 2))
{
return MEMCACHED_SUCCESS;
}
/* memcached_io_write and memcached_response may call memcached_purge
so we need to be able stop any recursion.. */
memcached_set_purging(root, true);
WATCHPOINT_ASSERT(ptr->fd != -1);
/* Force a flush of the buffer to ensure that we don't have the n-1 pending
requests buffered up.. */
if (memcached_io_write(ptr, NULL, 0, true) == -1)
{
memcached_set_purging(root, true);
return MEMCACHED_WRITE_FAILURE;
}
WATCHPOINT_ASSERT(ptr->fd != -1);
no_msg= memcached_server_response_count(ptr) - 1;
if (no_msg > 0)
{
memcached_result_st result;
memcached_result_st *result_ptr;
char buffer[SMALL_STRING_LEN];
/*
* We need to increase the timeout, because we might be waiting for
* data to be sent from the server (the commands was in the output buffer
* and just flushed
*/
const int32_t timeo= ptr->root->poll_timeout;
root->poll_timeout= 2000;
result_ptr= memcached_result_create(root, &result);
WATCHPOINT_ASSERT(result_ptr);
for (x= 0; x < no_msg; x++)
{
memcached_return_t rc;
memcached_result_reset(result_ptr);
rc= memcached_read_one_response(ptr, buffer,
sizeof (buffer),
result_ptr);
/*
* Purge doesn't care for what kind of command results that is received.
* The only kind of errors I care about if is I'm out of sync with the
* protocol or have problems reading data from the network..
*/
if (rc== MEMCACHED_PROTOCOL_ERROR || rc == MEMCACHED_UNKNOWN_READ_FAILURE)
{
WATCHPOINT_ERROR(rc);
ret = rc;
memcached_io_reset(ptr);
}
if (ptr->root->callbacks != NULL)
{
memcached_callback_st cb = *ptr->root->callbacks;
if (rc == MEMCACHED_SUCCESS)
{
uint32_t y;
for (y= 0; y < cb.number_of_callback; y++)
{
rc = (*cb.callback[y])(ptr->root, result_ptr, cb.context);
if (rc != MEMCACHED_SUCCESS)
break;
}
}
}
}
memcached_result_free(result_ptr);
root->poll_timeout= timeo;
}
memcached_set_purging(root, false);
return ret;
}
