diff options
| -rw-r--r-- | Makefile.am | 4 | ||||
| -rw-r--r-- | src/event/BufferedSocket.cxx | 256 | ||||
| -rw-r--r-- | src/event/BufferedSocket.hxx | 125 | ||||
| -rw-r--r-- | src/event/SocketMonitor.cxx | 108 | ||||
| -rw-r--r-- | src/event/SocketMonitor.hxx | 118 |
5 files changed, 610 insertions, 1 deletions
diff --git a/Makefile.am b/Makefile.am index 5f6ce85c4..eca6d7d7c 100644 --- a/Makefile.am +++ b/Makefile.am @@ -39,8 +39,8 @@ src_mpd_LDADD = \ $(FILTER_LIBS) \ $(ENCODER_LIBS) \ $(MIXER_LIBS) \ - libutil.a \ libevent.a \ + libutil.a \ $(SYSTEMD_DAEMON_LIBS) \ $(GLIB_LIBS) @@ -357,6 +357,8 @@ libutil_a_SOURCES = \ libevent_a_SOURCES = \ src/event/WakeFD.cxx src/event/WakeFD.hxx \ src/event/TimeoutMonitor.hxx src/event/TimeoutMonitor.cxx \ + src/event/SocketMonitor.cxx src/event/SocketMonitor.hxx \ + src/event/BufferedSocket.cxx src/event/BufferedSocket.hxx \ src/event/Loop.hxx # PCM library diff --git a/src/event/BufferedSocket.cxx b/src/event/BufferedSocket.cxx new file mode 100644 index 000000000..f84fe808b --- /dev/null +++ b/src/event/BufferedSocket.cxx @@ -0,0 +1,256 @@ +/* + * Copyright (C) 2003-2013 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "config.h" +#include "BufferedSocket.hxx" +#include "SocketError.hxx" +#include "util/fifo_buffer.h" + +#include <assert.h> +#include <stdint.h> +#include <string.h> + +#ifndef WIN32 +#include <sys/types.h> +#include <sys/socket.h> +#endif + +BufferedSocket::~BufferedSocket() +{ + if (input != nullptr) + fifo_buffer_free(input); +} + +BufferedSocket::ssize_t +BufferedSocket::DirectWrite(const void *data, size_t length) +{ + int flags = 0; +#ifdef MSG_NOSIGNAL + flags |= MSG_NOSIGNAL; +#endif +#ifdef MSG_DONTWAIT + flags |= MSG_DONTWAIT; +#endif + + const auto nbytes = send(Get(), (const char *)data, length, flags); + if (gcc_unlikely(nbytes < 0)) { + const auto code = GetSocketError(); + if (IsSocketErrorAgain(code)) + return 0; + + Cancel(); + + if (IsSocketErrorClosed(code)) + OnSocketClosed(); + else + OnSocketError(NewSocketError(code)); + } + + return nbytes; +} + +ssize_t +BufferedSocket::DirectRead(void *data, size_t length) +{ + int flags = 0; +#ifdef MSG_DONTWAIT + flags |= MSG_DONTWAIT; +#endif + + const auto nbytes = recv(Get(), (char *)data, length, flags); + if (gcc_likely(nbytes > 0)) + return nbytes; + + if (nbytes == 0) { + OnSocketClosed(); + return -1; + } + + const auto code = GetSocketError(); + if (IsSocketErrorAgain(code)) + return 0; + + if (IsSocketErrorClosed(code)) + OnSocketClosed(); + else + OnSocketError(NewSocketError(code)); + return -1; +} + +bool +BufferedSocket::WriteFromBuffer() +{ + assert(IsDefined()); + + size_t length; + const void *data = output.Read(&length); + if (data == nullptr) { + CancelWrite(); + return true; + } + + auto nbytes = DirectWrite(data, length); + if (gcc_unlikely(nbytes <= 0)) + return nbytes == 0; + + output.Consume(nbytes); + + if (output.IsEmpty()) + CancelWrite(); + + return true; +} + +bool +BufferedSocket::ReadToBuffer() +{ + assert(IsDefined()); + + if (input == nullptr) + input = fifo_buffer_new(8192); + + size_t length; + void *buffer = fifo_buffer_write(input, &length); + assert(buffer != nullptr); + + const auto nbytes = DirectRead(buffer, length); + if (nbytes > 0) + fifo_buffer_append(input, nbytes); + + return nbytes >= 0; +} + +bool +BufferedSocket::Write(const void *data, size_t length) +{ + assert(IsDefined()); + +#if 0 + /* TODO: disabled because this would add overhead on some callers (the ones that often), but it may be useful */ + + if (output.IsEmpty()) { + /* try to write it directly first */ + const auto nbytes = DirectWrite(data, length); + if (gcc_likely(nbytes > 0)) { + data = (const uint8_t *)data + nbytes; + length -= nbytes; + if (length == 0) + return true; + } else if (nbytes < 0) + return false; + } +#endif + + if (!output.Append(data, length)) { + // TODO + OnSocketError(g_error_new_literal(g_quark_from_static_string("buffered_socket"), + 0, "Output buffer is full")); + return false; + } + + ScheduleWrite(); + return true; +} + +bool +BufferedSocket::ResumeInput() +{ + assert(IsDefined()); + + if (input == nullptr) { + ScheduleRead(); + return true; + } + + while (true) { + size_t length; + const void *data = fifo_buffer_read(input, &length); + if (data == nullptr) { + ScheduleRead(); + return true; + } + + const auto result = OnSocketInput(data, length); + switch (result) { + case InputResult::MORE: + if (fifo_buffer_is_full(input)) { + // TODO + OnSocketError(g_error_new_literal(g_quark_from_static_string("buffered_socket"), + 0, "Input buffer is full")); + return false; + } + + ScheduleRead(); + return true; + + case InputResult::PAUSE: + CancelRead(); + return true; + + case InputResult::AGAIN: + continue; + + case InputResult::CLOSED: + return false; + } + } +} + +void +BufferedSocket::ConsumeInput(size_t nbytes) +{ + assert(IsDefined()); + + fifo_buffer_consume(input, nbytes); +} + +void +BufferedSocket::OnSocketReady(unsigned flags) +{ + assert(IsDefined()); + + if (gcc_unlikely(flags & (ERROR|HANGUP))) { + OnSocketClosed(); + return; + } + + if (flags & READ) { + assert(input == nullptr || !fifo_buffer_is_full(input)); + + if (!ReadToBuffer() || !ResumeInput()) + return; + + if (input == nullptr || !fifo_buffer_is_full(input)) + ScheduleRead(); + + /* just in case the OnSocketInput() method has added + data to the output buffer: try to send it now + instead of waiting for the next event loop + iteration */ + if (!output.IsEmpty()) + flags |= WRITE; + } + + if (flags & WRITE) { + assert(!output.IsEmpty()); + + if (!WriteFromBuffer()) + return; + } +} diff --git a/src/event/BufferedSocket.hxx b/src/event/BufferedSocket.hxx new file mode 100644 index 000000000..49b17c86f --- /dev/null +++ b/src/event/BufferedSocket.hxx @@ -0,0 +1,125 @@ +/* + * Copyright (C) 2003-2013 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef MPD_BUFFERED_SOCKET_HXX +#define MPD_BUFFERED_SOCKET_HXX + +#include "check.h" +#include "SocketMonitor.hxx" +#include "util/PeakBuffer.hxx" +#include "gcc.h" + +#include <type_traits> + +#include <stddef.h> + +struct fifo_buffer; +class EventLoop; + +class BufferedSocket : private SocketMonitor { + typedef std::make_signed<size_t>::type ssize_t; + + fifo_buffer *input; + PeakBuffer output; + +public: + BufferedSocket(int _fd, EventLoop &_loop, + size_t normal_size, size_t peak_size=0) + :SocketMonitor(_fd, _loop), input(nullptr), + output(normal_size, peak_size) { + ScheduleRead(); + } + + ~BufferedSocket(); + + using SocketMonitor::IsDefined; + using SocketMonitor::Close; + +private: + ssize_t DirectWrite(const void *data, size_t length); + ssize_t DirectRead(void *data, size_t length); + + /** + * Send data from the output buffer to the socket. + * + * @return false if the socket has been closed + */ + bool WriteFromBuffer(); + + /** + * Receive data from the socket to the input buffer. + * + * @return false if the socket has been closed + */ + bool ReadToBuffer(); + +protected: + /** + * @return false if the socket has been closed + */ + bool Write(const void *data, size_t length); + + /** + * @return false if the socket has been closed + */ + bool ResumeInput(); + + /** + * Mark a portion of the input buffer "consumed". Only + * allowed to be called from OnSocketInput(). This method + * does not invalidate the pointer passed to OnSocketInput() + * yet. + */ + void ConsumeInput(size_t nbytes); + + enum class InputResult { + /** + * The method was successful, and it is ready to + * read more data. + */ + MORE, + + /** + * The method does not want to get more data for now. + * It will call ResumeInput() when it's ready for + * more. + */ + PAUSE, + + /** + * The method wants to be called again immediately, if + * there's more data in the buffer. + */ + AGAIN, + + /** + * The method has closed the socket. + */ + CLOSED, + }; + + virtual InputResult OnSocketInput(const void *data, size_t length) = 0; + virtual void OnSocketError(GError *error) = 0; + virtual void OnSocketClosed() = 0; + +private: + virtual void OnSocketReady(unsigned flags) override; +}; + +#endif diff --git a/src/event/SocketMonitor.cxx b/src/event/SocketMonitor.cxx new file mode 100644 index 000000000..ec31647f2 --- /dev/null +++ b/src/event/SocketMonitor.cxx @@ -0,0 +1,108 @@ +/* + * Copyright (C) 2003-2013 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "config.h" +#include "SocketMonitor.hxx" +#include "Loop.hxx" +#include "fd_util.h" +#include "gcc.h" + +#include <assert.h> + +/* + * GSource methods + * + */ + +gboolean +SocketMonitor::Prepare(gcc_unused GSource *source, gcc_unused gint *timeout_r) +{ + return false; +} + +gboolean +SocketMonitor::Check(GSource *_source) +{ + const Source &source = *(const Source *)_source; + const SocketMonitor &monitor = *source.monitor; + assert(_source == &monitor.source->base); + + return monitor.Check(); +} + +gboolean +SocketMonitor::Dispatch(GSource *_source, + gcc_unused GSourceFunc callback, + gcc_unused gpointer user_data) +{ + Source &source = *(Source *)_source; + SocketMonitor &monitor = *source.monitor; + assert(_source == &monitor.source->base); + + monitor.Dispatch(); + return true; +} + +/** + * The vtable for our GSource implementation. Unfortunately, we + * cannot declare it "const", because g_source_new() takes a non-const + * pointer, for whatever reason. + */ +static GSourceFuncs socket_monitor_source_funcs = { + SocketMonitor::Prepare, + SocketMonitor::Check, + SocketMonitor::Dispatch, + nullptr, + nullptr, + nullptr, +}; + +SocketMonitor::SocketMonitor(int _fd, EventLoop &_loop) + :fd(_fd), loop(_loop), + source((Source *)g_source_new(&socket_monitor_source_funcs, + sizeof(*source))), + poll{fd, 0, 0} { + assert(fd >= 0); + + source->monitor = this; + + g_source_attach(&source->base, loop.GetContext()); + g_source_add_poll(&source->base, &poll); +} + +SocketMonitor::~SocketMonitor() +{ + if (IsDefined()) + Close(); +} + +void +SocketMonitor::Close() +{ + assert(IsDefined()); + + Cancel(); + + close_socket(fd); + fd = -1; + + g_source_destroy(&source->base); + g_source_unref(&source->base); + source = nullptr; +} diff --git a/src/event/SocketMonitor.hxx b/src/event/SocketMonitor.hxx new file mode 100644 index 000000000..ca3c5dcc4 --- /dev/null +++ b/src/event/SocketMonitor.hxx @@ -0,0 +1,118 @@ +/* + * Copyright (C) 2003-2013 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#ifndef MPD_SOCKET_MONITOR_HXX +#define MPD_SOCKET_MONITOR_HXX + +#include "check.h" + +#include <glib.h> + +#include <assert.h> + +#ifdef WIN32 +/* ERRORis a WIN32 macro that poisons our namespace; this is a + kludge to allow us to use it anyway */ +#ifdef ERROR +#undef ERROR +#endif +#endif + +class EventLoop; + +class SocketMonitor { + struct Source { + GSource base; + + SocketMonitor *monitor; + }; + + int fd; + EventLoop &loop; + Source *source; + GPollFD poll; + +public: + static constexpr unsigned READ = G_IO_IN; + static constexpr unsigned WRITE = G_IO_OUT; + static constexpr unsigned ERROR = G_IO_ERR; + static constexpr unsigned HANGUP = G_IO_HUP; + + SocketMonitor(int _fd, EventLoop &_loop); + + ~SocketMonitor(); + + bool IsDefined() const { + return fd >= 0; + } + + int Get() const { + assert(IsDefined()); + + return fd; + } + + void Close(); + + void Schedule(unsigned flags) { + poll.events = flags; + poll.revents &= flags; + } + + void Cancel() { + poll.events = 0; + } + + void ScheduleRead() { + poll.events |= READ|HANGUP|ERROR; + } + + void ScheduleWrite() { + poll.events |= WRITE; + } + + void CancelRead() { + poll.events &= ~(READ|HANGUP|ERROR); + } + + void CancelWrite() { + poll.events &= ~WRITE; + } + +protected: + virtual void OnSocketReady(unsigned flags) = 0; + +public: + /* GSource callbacks */ + static gboolean Prepare(GSource *source, gint *timeout_r); + static gboolean Check(GSource *source); + static gboolean Dispatch(GSource *source, GSourceFunc callback, + gpointer user_data); + +private: + bool Check() const { + return (poll.revents & poll.events) != 0; + } + + void Dispatch() { + OnSocketReady(poll.revents & poll.events); + } +}; + +#endif |