--- /dev/null
+/* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
+ *
+ * LibMemcached
+ *
+ * Copyright (C) 2011 Data Differential, http://datadifferential.com/
+ * Copyright (C) 2006-2009 Brian Aker
+ * All rights reserved.
+ *
+ * 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.
+ *
+ */
+
+
+#include <libmemcached/common.h>
+
+#ifdef HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+#endif
+
+void initialize_binary_request(memcached_instance_st* server, protocol_binary_request_header& header)
+{
+ server->request_id++;
+ header.request.magic= PROTOCOL_BINARY_REQ;
+ header.request.opaque= htons(server->request_id);
+}
+
+enum memc_read_or_write {
+ MEM_READ,
+ MEM_WRITE
+};
+
+/**
+ * Try to fill the input buffer for a server with as much
+ * data as possible.
+ *
+ * @param instance the server to pack
+ */
+static bool repack_input_buffer(memcached_instance_st* instance)
+{
+ if (instance->read_ptr != instance->read_buffer)
+ {
+ /* Move all of the data to the beginning of the buffer so
+ ** that we can fit more data into the buffer...
+ */
+ memmove(instance->read_buffer, instance->read_ptr, instance->read_buffer_length);
+ instance->read_ptr= instance->read_buffer;
+ }
+
+ /* There is room in the buffer, try to fill it! */
+ if (instance->read_buffer_length != MEMCACHED_MAX_BUFFER)
+ {
+ do {
+ /* Just try a single read to grab what's available */
+ ssize_t nr;
+ if ((nr= ::recv(instance->fd,
+ instance->read_ptr + instance->read_buffer_length,
+ MEMCACHED_MAX_BUFFER - instance->read_buffer_length,
+ MSG_NOSIGNAL)) <= 0)
+ {
+ if (nr == 0)
+ {
+ memcached_set_error(*instance, MEMCACHED_CONNECTION_FAILURE, MEMCACHED_AT);
+ }
+ else
+ {
+ switch (get_socket_errno())
+ {
+ case EINTR:
+ continue;
+
+#if EWOULDBLOCK != EAGAIN
+ case EWOULDBLOCK:
+#endif
+ case EAGAIN:
+#ifdef __linux
+ case ERESTART:
+#endif
+ break; // No IO is fine, we can just move on
+
+ default:
+ memcached_set_errno(*instance, get_socket_errno(), MEMCACHED_AT);
+ }
+ }
+
+ break;
+ }
+ else // We read data, append to our read buffer
+ {
+ instance->read_buffer_length+= size_t(nr);
+
+ return true;
+ }
+ } while (false);
+ }
+
+ return false;
+}
+
+/**
+ * If the we have callbacks connected to this server structure
+ * we may start process the input queue and fire the callbacks
+ * for the incomming messages. This function is _only_ called
+ * when the input buffer is full, so that we _know_ that we have
+ * at least _one_ message to process.
+ *
+ * @param instance the server to star processing iput messages for
+ * @return true if we processed anything, false otherwise
+ */
+static bool process_input_buffer(memcached_instance_st* instance)
+{
+ /*
+ ** We might be able to process some of the response messages if we
+ ** have a callback set up
+ */
+ if (instance->root->callbacks != NULL)
+ {
+ /*
+ * We might have responses... try to read them out and fire
+ * callbacks
+ */
+ memcached_callback_st cb= *instance->root->callbacks;
+
+ memcached_set_processing_input((Memcached *)instance->root, true);
+
+ char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
+ Memcached *root= (Memcached *)instance->root;
+ memcached_return_t error= memcached_response(instance, buffer, sizeof(buffer), &root->result);
+
+ memcached_set_processing_input(root, false);
+
+ if (error == MEMCACHED_SUCCESS)
+ {
+ for (unsigned int x= 0; x < cb.number_of_callback; x++)
+ {
+ error= (*cb.callback[x])(instance->root, &root->result, cb.context);
+ if (error != MEMCACHED_SUCCESS)
+ {
+ break;
+ }
+ }
+
+ /* @todo what should I do with the error message??? */
+ }
+ /* @todo what should I do with other error messages?? */
+ return true;
+ }
+
+ return false;
+}
+
+static memcached_return_t io_wait(memcached_instance_st* instance,
+ const short events)
+{
+ /*
+ ** We are going to block on write, but at least on Solaris we might block
+ ** on write if we haven't read anything from our input buffer..
+ ** Try to purge the input buffer if we don't do any flow control in the
+ ** application layer (just sending a lot of data etc)
+ ** The test is moved down in the purge function to avoid duplication of
+ ** the test.
+ */
+ if (events & POLLOUT)
+ {
+ if (memcached_purge(instance) == false)
+ {
+ return MEMCACHED_FAILURE;
+ }
+ }
+
+ struct pollfd fds;
+ fds.fd= instance->fd;
+ fds.events= events;
+ fds.revents= 0;
+
+ if (fds.events & POLLOUT) /* write */
+ {
+ instance->io_wait_count.write++;
+ }
+ else
+ {
+ instance->io_wait_count.read++;
+ }
+
+ if (instance->root->poll_timeout == 0) // Mimic 0 causes timeout behavior (not all platforms do this)
+ {
+ return memcached_set_error(*instance, MEMCACHED_TIMEOUT, MEMCACHED_AT, memcached_literal_param("poll_timeout() was set to zero"));
+ }
+
+ size_t loop_max= 5;
+ while (--loop_max) // While loop is for ERESTART or EINTR
+ {
+ int active_fd= poll(&fds, 1, instance->root->poll_timeout);
+
+ if (active_fd >= 1)
+ {
+ assert_msg(active_fd == 1 , "poll() returned an unexpected number of active file descriptors");
+ if (fds.revents & POLLIN or fds.revents & POLLOUT)
+ {
+ return MEMCACHED_SUCCESS;
+ }
+
+ if (fds.revents & POLLHUP)
+ {
+ return memcached_set_error(*instance, MEMCACHED_CONNECTION_FAILURE, MEMCACHED_AT,
+ memcached_literal_param("poll() detected hang up"));
+ }
+
+ if (fds.revents & POLLERR)
+ {
+ int local_errno= EINVAL;
+ int err;
+ socklen_t len= sizeof (err);
+ if (getsockopt(instance->fd, SOL_SOCKET, SO_ERROR, (char*)&err, &len) == 0)
+ {
+ if (err == 0) // treat this as EINTR
+ {
+ continue;
+ }
+ local_errno= err;
+ }
+ memcached_quit_server(instance, true);
+ return memcached_set_errno(*instance, local_errno, MEMCACHED_AT,
+ memcached_literal_param("poll() returned POLLHUP"));
+ }
+
+ return memcached_set_error(*instance, MEMCACHED_FAILURE, MEMCACHED_AT, memcached_literal_param("poll() returned a value that was not dealt with"));
+ }
+
+ if (active_fd == 0)
+ {
+ return memcached_set_error(*instance, MEMCACHED_TIMEOUT, MEMCACHED_AT, memcached_literal_param("No active_fd were found"));
+ }
+
+ // Only an error should result in this code being called.
+ int local_errno= get_socket_errno(); // We cache in case memcached_quit_server() modifies errno
+ assert_msg(active_fd == -1 , "poll() returned an unexpected value");
+ switch (local_errno)
+ {
+#ifdef __linux
+ case ERESTART:
+#endif
+ case EINTR:
+ continue;
+
+ case EFAULT:
+ case ENOMEM:
+ memcached_set_error(*instance, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
+ break;
+
+ case EINVAL:
+ memcached_set_error(*instance, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT, memcached_literal_param("RLIMIT_NOFILE exceeded, or if OSX the timeout value was invalid"));
+ break;
+
+ default:
+ memcached_set_errno(*instance, local_errno, MEMCACHED_AT, memcached_literal_param("poll"));
+ }
+
+ break;
+ }
+
+ memcached_quit_server(instance, true);
+
+ if (memcached_has_error(instance))
+ {
+ return memcached_instance_error_return(instance);
+ }
+
+ return memcached_set_error(*instance, MEMCACHED_CONNECTION_FAILURE, MEMCACHED_AT,
+ memcached_literal_param("number of attempts to call io_wait() failed"));
+}
+
+static bool io_flush(memcached_instance_st* instance,
+ const bool with_flush,
+ memcached_return_t& error)
+{
+ /*
+ ** We might want to purge the input buffer if we haven't consumed
+ ** any output yet... The test for the limits is the purge is inline
+ ** in the purge function to avoid duplicating the logic..
+ */
+ {
+ WATCHPOINT_ASSERT(instance->fd != INVALID_SOCKET);
+
+ if (memcached_purge(instance) == false)
+ {
+ return false;
+ }
+ }
+ char *local_write_ptr= instance->write_buffer;
+ size_t write_length= instance->write_buffer_offset;
+
+ error= MEMCACHED_SUCCESS;
+
+ WATCHPOINT_ASSERT(instance->fd != INVALID_SOCKET);
+
+ /* Looking for memory overflows */
+#if defined(DEBUG)
+ if (write_length == MEMCACHED_MAX_BUFFER)
+ WATCHPOINT_ASSERT(instance->write_buffer == local_write_ptr);
+ WATCHPOINT_ASSERT((instance->write_buffer + MEMCACHED_MAX_BUFFER) >= (local_write_ptr + write_length));
+#endif
+
+ while (write_length)
+ {
+ WATCHPOINT_ASSERT(instance->fd != INVALID_SOCKET);
+ WATCHPOINT_ASSERT(write_length > 0);
+
+ int flags;
+ if (with_flush)
+ {
+ flags= MSG_NOSIGNAL;
+ }
+ else
+ {
+ flags= MSG_NOSIGNAL|MSG_MORE;
+ }
+
+ ssize_t sent_length= ::send(instance->fd, local_write_ptr, write_length, flags);
+ int local_errno= get_socket_errno(); // We cache in case memcached_quit_server() modifies errno
+
+ if (sent_length == SOCKET_ERROR)
+ {
+#if 0 // @todo I should look at why we hit this bit of code hard frequently
+ WATCHPOINT_ERRNO(get_socket_errno());
+ WATCHPOINT_NUMBER(get_socket_errno());
+#endif
+ switch (get_socket_errno())
+ {
+ case ENOBUFS:
+ continue;
+
+#if EWOULDBLOCK != EAGAIN
+ case EWOULDBLOCK:
+#endif
+ case EAGAIN:
+ {
+ /*
+ * We may be blocked on write because the input buffer
+ * is full. Let's check if we have room in our input
+ * buffer for more data and retry the write before
+ * waiting..
+ */
+ if (repack_input_buffer(instance) or process_input_buffer(instance))
+ {
+ continue;
+ }
+
+ memcached_return_t rc= io_wait(instance, POLLOUT);
+ if (memcached_success(rc))
+ {
+ continue;
+ }
+ else if (rc == MEMCACHED_TIMEOUT)
+ {
+ return false;
+ }
+
+ memcached_quit_server(instance, true);
+ error= memcached_set_errno(*instance, local_errno, MEMCACHED_AT);
+ return false;
+ }
+ case ENOTCONN:
+ case EPIPE:
+ default:
+ memcached_quit_server(instance, true);
+ error= memcached_set_errno(*instance, local_errno, MEMCACHED_AT);
+ WATCHPOINT_ASSERT(instance->fd == INVALID_SOCKET);
+ return false;
+ }
+ }
+
+ instance->io_bytes_sent+= uint32_t(sent_length);
+
+ local_write_ptr+= sent_length;
+ write_length-= uint32_t(sent_length);
+ }
+
+ WATCHPOINT_ASSERT(write_length == 0);
+ instance->write_buffer_offset= 0;
+
+ return true;
+}
+
+memcached_return_t memcached_io_wait_for_write(memcached_instance_st* instance)
+{
+ return io_wait(instance, POLLOUT);
+}
+
+memcached_return_t memcached_io_wait_for_read(memcached_instance_st* instance)
+{
+ return io_wait(instance, POLLIN);
+}
+
+static memcached_return_t _io_fill(memcached_instance_st* instance)
+{
+ ssize_t data_read;
+ do
+ {
+ data_read= ::recv(instance->fd, instance->read_buffer, MEMCACHED_MAX_BUFFER, MSG_NOSIGNAL);
+ int local_errno= get_socket_errno(); // We cache in case memcached_quit_server() modifies errno
+
+ if (data_read == SOCKET_ERROR)
+ {
+ switch (get_socket_errno())
+ {
+ case EINTR: // We just retry
+ continue;
+
+ case ETIMEDOUT: // OSX
+#if EWOULDBLOCK != EAGAIN
+ case EWOULDBLOCK:
+#endif
+ case EAGAIN:
+#ifdef __linux
+ case ERESTART:
+#endif
+ {
+ memcached_return_t io_wait_ret;
+ if (memcached_success(io_wait_ret= io_wait(instance, POLLIN)))
+ {
+ continue;
+ }
+
+ return io_wait_ret;
+ }
+
+ /* fall through */
+
+ case ENOTCONN: // Programmer Error
+ WATCHPOINT_ASSERT(0);
+ // fall through
+ case ENOTSOCK:
+ WATCHPOINT_ASSERT(0);
+ // fall through
+ case EBADF:
+ assert_msg(instance->fd != INVALID_SOCKET, "Programmer error, invalid socket");
+ /* fall through */
+ case EINVAL:
+ case EFAULT:
+ case ECONNREFUSED:
+ default:
+ memcached_quit_server(instance, true);
+ memcached_set_errno(*instance, local_errno, MEMCACHED_AT);
+ break;
+ }
+
+ return memcached_instance_error_return(instance);
+ }
+ else if (data_read == 0)
+ {
+ /*
+ EOF. Any data received so far is incomplete
+ so discard it. This always reads by byte in case of TCP
+ and protocol enforcement happens at memcached_response()
+ looking for '\n'. We do not care for UDB which requests 8 bytes
+ at once. Generally, this means that connection went away. Since
+ for blocking I/O we do not return 0 and for non-blocking case
+ it will return EGAIN if data is not immediatly available.
+ */
+ memcached_quit_server(instance, true);
+ return memcached_set_error(*instance, MEMCACHED_CONNECTION_FAILURE, MEMCACHED_AT,
+ memcached_literal_param("::rec() returned zero, server has disconnected"));
+ }
+ instance->io_wait_count._bytes_read+= data_read;
+ } while (data_read <= 0);
+
+ instance->io_bytes_sent= 0;
+ instance->read_buffer_length= (size_t) data_read;
+ instance->read_ptr= instance->read_buffer;
+
+ return MEMCACHED_SUCCESS;
+}
+
+memcached_return_t memcached_io_read(memcached_instance_st* instance,
+ void *buffer, size_t length, ssize_t& nread)
+{
+ assert(memcached_is_udp(instance->root) == false);
+ assert_msg(instance, "Programmer error, memcached_io_read() recieved an invalid Instance"); // Programmer error
+ char *buffer_ptr= static_cast<char *>(buffer);
+
+ if (instance->fd == INVALID_SOCKET)
+ {
+#if 0
+ assert_msg(int(instance->state) <= int(MEMCACHED_SERVER_STATE_ADDRINFO), "Programmer error, invalid socket state");
+#endif
+ return MEMCACHED_CONNECTION_FAILURE;
+ }
+
+ while (length)
+ {
+ if (instance->read_buffer_length == 0)
+ {
+ memcached_return_t io_fill_ret;
+ if (memcached_fatal(io_fill_ret= _io_fill(instance)))
+ {
+ nread= -1;
+ return io_fill_ret;
+ }
+ }
+
+ if (length > 1)
+ {
+ size_t difference= (length > instance->read_buffer_length) ? instance->read_buffer_length : length;
+
+ memcpy(buffer_ptr, instance->read_ptr, difference);
+ length -= difference;
+ instance->read_ptr+= difference;
+ instance->read_buffer_length-= difference;
+ buffer_ptr+= difference;
+ }
+ else
+ {
+ *buffer_ptr= *instance->read_ptr;
+ instance->read_ptr++;
+ instance->read_buffer_length--;
+ buffer_ptr++;
+ break;
+ }
+ }
+
+ nread= ssize_t(buffer_ptr - (char*)buffer);
+
+ return MEMCACHED_SUCCESS;
+}
+
+memcached_return_t memcached_io_slurp(memcached_instance_st* instance)
+{
+ assert_msg(instance, "Programmer error, invalid Instance");
+ assert(memcached_is_udp(instance->root) == false);
+
+ if (instance->fd == INVALID_SOCKET)
+ {
+ assert_msg(int(instance->state) <= int(MEMCACHED_SERVER_STATE_ADDRINFO), "Invalid socket state");
+ return MEMCACHED_CONNECTION_FAILURE;
+ }
+
+ ssize_t data_read;
+ char buffer[MEMCACHED_MAX_BUFFER];
+ do
+ {
+ data_read= ::recv(instance->fd, instance->read_buffer, sizeof(buffer), MSG_NOSIGNAL);
+ if (data_read == SOCKET_ERROR)
+ {
+ switch (get_socket_errno())
+ {
+ case EINTR: // We just retry
+ continue;
+
+ case ETIMEDOUT: // OSX
+#if EWOULDBLOCK != EAGAIN
+ case EWOULDBLOCK:
+#endif
+ case EAGAIN:
+#ifdef __linux
+ case ERESTART:
+#endif
+ if (memcached_success(io_wait(instance, POLLIN)))
+ {
+ continue;
+ }
+ return MEMCACHED_IN_PROGRESS;
+
+ /* fall through */
+
+ case ENOTCONN: // Programmer Error
+ case ENOTSOCK:
+ assert(0);
+ /* fall through */
+ case EBADF:
+ assert_msg(instance->fd != INVALID_SOCKET, "Invalid socket state");
+ /* fall through */
+ case EINVAL:
+ case EFAULT:
+ case ECONNREFUSED:
+ default:
+ return MEMCACHED_CONNECTION_FAILURE; // We want this!
+ }
+ }
+ } while (data_read > 0);
+
+ return MEMCACHED_CONNECTION_FAILURE;
+}
+
+static bool _io_write(memcached_instance_st* instance,
+ const void *buffer, size_t length, bool with_flush,
+ size_t& written)
+{
+ assert(instance->fd != INVALID_SOCKET);
+ assert(memcached_is_udp(instance->root) == false);
+
+ const char *buffer_ptr= static_cast<const char *>(buffer);
+
+ const size_t original_length= length;
+
+ while (length)
+ {
+ char *write_ptr;
+ size_t buffer_end= MEMCACHED_MAX_BUFFER;
+ size_t should_write= buffer_end -instance->write_buffer_offset;
+ should_write= (should_write < length) ? should_write : length;
+
+ write_ptr= instance->write_buffer + instance->write_buffer_offset;
+ memcpy(write_ptr, buffer_ptr, should_write);
+ instance->write_buffer_offset+= should_write;
+ buffer_ptr+= should_write;
+ length-= should_write;
+
+ if (instance->write_buffer_offset == buffer_end)
+ {
+ WATCHPOINT_ASSERT(instance->fd != INVALID_SOCKET);
+
+ memcached_return_t rc;
+ if (io_flush(instance, with_flush, rc) == false)
+ {
+ written= original_length -length;
+ return false;
+ }
+ }
+ }
+
+ if (with_flush)
+ {
+ memcached_return_t rc;
+ WATCHPOINT_ASSERT(instance->fd != INVALID_SOCKET);
+ if (io_flush(instance, with_flush, rc) == false)
+ {
+ written= original_length -length;
+ return false;
+ }
+ }
+
+ written= original_length -length;
+
+ return true;
+}
+
+bool memcached_io_write(memcached_instance_st* instance)
+{
+ size_t written;
+ return _io_write(instance, NULL, 0, true, written);
+}
+
+ssize_t memcached_io_write(memcached_instance_st* instance,
+ const void *buffer, const size_t length, const bool with_flush)
+{
+ size_t written;
+
+ if (_io_write(instance, buffer, length, with_flush, written) == false)
+ {
+ return -1;
+ }
+
+ return ssize_t(written);
+}
+
+bool memcached_io_writev(memcached_instance_st* instance,
+ libmemcached_io_vector_st vector[],
+ const size_t number_of, const bool with_flush)
+{
+ ssize_t complete_total= 0;
+ ssize_t total= 0;
+
+ for (size_t x= 0; x < number_of; x++, vector++)
+ {
+ complete_total+= vector->length;
+ if (vector->length)
+ {
+ size_t written;
+ if ((_io_write(instance, vector->buffer, vector->length, false, written)) == false)
+ {
+ return false;
+ }
+ total+= written;
+ }
+ }
+
+ if (with_flush)
+ {
+ if (memcached_io_write(instance) == false)
+ {
+ return false;
+ }
+ }
+
+ return (complete_total == total);
+}
+
+void memcached_instance_st::start_close_socket()
+{
+ if (fd != INVALID_SOCKET)
+ {
+ shutdown(fd, SHUT_WR);
+ options.is_shutting_down= true;
+ }
+}
+
+void memcached_instance_st::reset_socket()
+{
+ if (fd != INVALID_SOCKET)
+ {
+ (void)closesocket(fd);
+ fd= INVALID_SOCKET;
+ }
+}
+
+void memcached_instance_st::close_socket()
+{
+ if (fd != INVALID_SOCKET)
+ {
+ int shutdown_options= SHUT_RD;
+ if (options.is_shutting_down == false)
+ {
+ shutdown_options= SHUT_RDWR;
+ }
+
+ /* in case of death shutdown to avoid blocking at close() */
+ if (shutdown(fd, shutdown_options) == SOCKET_ERROR and get_socket_errno() != ENOTCONN)
+ {
+ WATCHPOINT_NUMBER(fd);
+ WATCHPOINT_ERRNO(get_socket_errno());
+ WATCHPOINT_ASSERT(get_socket_errno());
+ }
+
+ reset_socket();
+ state= MEMCACHED_SERVER_STATE_NEW;
+ }
+
+ state= MEMCACHED_SERVER_STATE_NEW;
+ cursor_active_= 0;
+ io_bytes_sent= 0;
+ write_buffer_offset= size_t(root and memcached_is_udp(root) ? UDP_DATAGRAM_HEADER_LENGTH : 0);
+ read_buffer_length= 0;
+ read_ptr= read_buffer;
+ options.is_shutting_down= false;
+ memcached_server_response_reset(this);
+
+ // We reset the version so that if we end up talking to a different server
+ // we don't have stale server version information.
+ major_version= minor_version= micro_version= UINT8_MAX;
+}
+
+memcached_instance_st* memcached_io_get_readable_server(Memcached *memc, memcached_return_t&)
+{
+#define MAX_SERVERS_TO_POLL 100
+ struct pollfd fds[MAX_SERVERS_TO_POLL];
+ nfds_t host_index= 0;
+
+ for (uint32_t x= 0; x < memcached_server_count(memc) and host_index < MAX_SERVERS_TO_POLL; ++x)
+ {
+ memcached_instance_st* instance= memcached_instance_fetch(memc, x);
+
+ if (instance->read_buffer_length > 0) /* I have data in the buffer */
+ {
+ return instance;
+ }
+
+ if (instance->response_count() > 0)
+ {
+ fds[host_index].events= POLLIN;
+ fds[host_index].revents= 0;
+ fds[host_index].fd= instance->fd;
+ ++host_index;
+ }
+ }
+
+ if (host_index < 2)
+ {
+ /* We have 0 or 1 server with pending events.. */
+ for (uint32_t x= 0; x< memcached_server_count(memc); ++x)
+ {
+ memcached_instance_st* instance= memcached_instance_fetch(memc, x);
+
+ if (instance->response_count() > 0)
+ {
+ return instance;
+ }
+ }
+
+ return NULL;
+ }
+
+ int error= poll(fds, host_index, memc->poll_timeout);
+ switch (error)
+ {
+ case -1:
+ memcached_set_errno(*memc, get_socket_errno(), MEMCACHED_AT);
+ /* FALLTHROUGH */
+ case 0:
+ break;
+
+ default:
+ for (nfds_t x= 0; x < host_index; ++x)
+ {
+ if (fds[x].revents & POLLIN)
+ {
+ for (uint32_t y= 0; y < memcached_server_count(memc); ++y)
+ {
+ memcached_instance_st* instance= memcached_instance_fetch(memc, y);
+
+ if (instance->fd == fds[x].fd)
+ {
+ return instance;
+ }
+ }
+ }
+ }
+ }
+
+ return NULL;
+}
+
+/*
+ Eventually we will just kill off the server with the problem.
+*/
+void memcached_io_reset(memcached_instance_st* instance)
+{
+ memcached_quit_server(instance, true);
+}
+
+/**
+ * Read a given number of bytes from the server and place it into a specific
+ * buffer. Reset the IO channel on this server if an error occurs.
+ */
+memcached_return_t memcached_safe_read(memcached_instance_st* instance,
+ void *dta,
+ const size_t size)
+{
+ size_t offset= 0;
+ char *data= static_cast<char *>(dta);
+
+ while (offset < size)
+ {
+ ssize_t nread;
+ memcached_return_t rc;
+
+ while (memcached_continue(rc= memcached_io_read(instance, data + offset, size - offset, nread))) { };
+
+ if (memcached_failed(rc))
+ {
+ return rc;
+ }
+
+ offset+= size_t(nread);
+ }
+
+ return MEMCACHED_SUCCESS;
+}
+
+memcached_return_t memcached_io_readline(memcached_instance_st* instance,
+ char *buffer_ptr,
+ size_t size,
+ size_t& total_nr)
+{
+ total_nr= 0;
+ bool line_complete= false;
+
+ while (line_complete == false)
+ {
+ if (instance->read_buffer_length == 0)
+ {
+ /*
+ * We don't have any data in the buffer, so let's fill the read
+ * buffer. Call the standard read function to avoid duplicating
+ * the logic.
+ */
+ ssize_t nread;
+ memcached_return_t rc= memcached_io_read(instance, buffer_ptr, 1, nread);
+ if (memcached_failed(rc) and rc == MEMCACHED_IN_PROGRESS)
+ {
+ memcached_quit_server(instance, true);
+ return memcached_set_error(*instance, rc, MEMCACHED_AT);
+ }
+ else if (memcached_failed(rc))
+ {
+ return rc;
+ }
+
+ if (*buffer_ptr == '\n')
+ {
+ line_complete= true;
+ }
+
+ ++buffer_ptr;
+ ++total_nr;
+ }
+
+ /* Now let's look in the buffer and copy as we go! */
+ while (instance->read_buffer_length and total_nr < size and line_complete == false)
+ {
+ *buffer_ptr = *instance->read_ptr;
+ if (*buffer_ptr == '\n')
+ {
+ line_complete = true;
+ }
+ --instance->read_buffer_length;
+ ++instance->read_ptr;
+ ++total_nr;
+ ++buffer_ptr;
+ }
+
+ if (total_nr == size)
+ {
+ return MEMCACHED_PROTOCOL_ERROR;
+ }
+ }
+
+ return MEMCACHED_SUCCESS;
+}
projects / awesomized / libmemcached / blobdiff