/* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
*
* Libmemcached library
*
* Copyright (C) 2011 Data Differential, http://datadifferential.com/
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
*
* * The names of its contributors may not be used to endorse or
* promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
/*
We use this to dump all keys.
At this point we only support a callback method. This could be optimized by first
calling items and finding active slabs. For the moment though we just loop through
all slabs on servers and "grab" the keys.
*/
#include <libmemcached/common.h>
static memcached_return_t ascii_dump(Memcached *memc, memcached_dump_fn *callback, void *context, uint32_t number_of_callbacks)
{
/* MAX_NUMBER_OF_SLAB_CLASSES is defined to 200 in Memcached 1.4.10 */
for (uint32_t x= 0; x < 200; x++)
{
char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
int buffer_length= snprintf(buffer, sizeof(buffer), "%u", x);
if (size_t(buffer_length) >= sizeof(buffer) or buffer_length < 0)
{
return memcached_set_error(*memc, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT,
memcached_literal_param("snprintf(MEMCACHED_DEFAULT_COMMAND_SIZE)"));
}
// @NOTE the hard coded zero means "no limit"
libmemcached_io_vector_st vector[]=
{
{ memcached_literal_param("stats cachedump ") },
{ buffer, size_t(buffer_length) },
{ memcached_literal_param(" 0\r\n") }
};
// Send message to all servers
for (uint32_t server_key= 0; server_key < memcached_server_count(memc); server_key++)
{
memcached_instance_st* instance= memcached_instance_fetch(memc, server_key);
memcached_return_t vdo_rc;
if (memcached_success((vdo_rc= memcached_vdo(instance, vector, 3, true))))
{
// We have sent the message to the server successfully
}
else
{
return vdo_rc;
}
}
// Collect the returned items
memcached_instance_st* instance;
memcached_return_t read_ret= MEMCACHED_SUCCESS;
while ((instance= memcached_io_get_readable_server(memc, read_ret)))
{
memcached_return_t response_rc= memcached_response(instance, buffer, MEMCACHED_DEFAULT_COMMAND_SIZE, NULL);
if (response_rc == MEMCACHED_ITEM)
{
char *string_ptr, *end_ptr;
string_ptr= buffer;
string_ptr+= 5; /* Move past ITEM */
for (end_ptr= string_ptr; isgraph(*end_ptr); end_ptr++) {} ;
char *key= string_ptr;
key[(size_t)(end_ptr-string_ptr)]= 0;
for (uint32_t callback_counter= 0; callback_counter < number_of_callbacks; callback_counter++)
{
memcached_return_t callback_rc= (*callback[callback_counter])(memc, key, (size_t)(end_ptr-string_ptr), context);
if (callback_rc != MEMCACHED_SUCCESS)
{
// @todo build up a message for the error from the value
memcached_set_error(*instance, callback_rc, MEMCACHED_AT);
break;
}
}
}
else if (response_rc == MEMCACHED_END)
{
// All items have been returned
}
else if (response_rc == MEMCACHED_SERVER_ERROR or response_rc == MEMCACHED_CLIENT_ERROR or response_rc == MEMCACHED_ERROR)
{
/* If we try to request stats cachedump for a slab class that is too big
* the server will return an incorrect error message:
* "MEMCACHED_SERVER_ERROR failed to allocate memory"
* This isn't really a fatal error, so let's just skip it. I want to
* fix the return value from the memcached server to a CLIENT_ERROR,
* so let's add support for that as well right now.
*/
assert(response_rc == MEMCACHED_SUCCESS); // Just fail
return response_rc;
}
else
{
// IO error of some sort must have occurred
return response_rc;
}
}
}
return memcached_has_current_error(*memc) ? MEMCACHED_SOME_ERRORS : MEMCACHED_SUCCESS;
}
memcached_return_t memcached_dump(memcached_st *shell, memcached_dump_fn *callback, void *context, uint32_t number_of_callbacks)
{
Memcached* ptr= memcached2Memcached(shell);
memcached_return_t rc;
if (memcached_failed(rc= initialize_query(ptr, true)))
{
return rc;
}
/*
No support for Binary protocol yet
@todo Fix this so that we just flush, switch to ascii, and then go back to binary.
*/
if (memcached_is_binary(ptr))
{
return memcached_set_error(*ptr, MEMCACHED_NOT_SUPPORTED, MEMCACHED_AT, memcached_literal_param("Binary protocol is not supported for memcached_dump()"));
}
return ascii_dump(ptr, callback, context, number_of_callbacks);
}