[Spice-devel] [PATCH 09/22] Move read, write, handle and locking into the 'Stream' class
Frediano Ziglio
fziglio at redhat.com
Thu Mar 1 10:59:40 UTC 2018
>
> From: Christophe de Dinechin <dinechin at redhat.com>
>
> The 'Stream' class is designed to abstract file I/O. In a subsequent
> patch, message formatting will be isolated out of the class, but in
> order to minimize code changes, this intermediate step simply moves
> the corresponding functions within the Stream class.
>
> Signed-off-by: Christophe de Dinechin <dinechin at redhat.com>
> ---
> src/spice-streaming-agent.cpp | 108
> +++++++++++++++++++++++-------------------
> 1 file changed, 58 insertions(+), 50 deletions(-)
>
> diff --git a/src/spice-streaming-agent.cpp b/src/spice-streaming-agent.cpp
> index 21f9c31..4d24234 100644
> --- a/src/spice-streaming-agent.cpp
> +++ b/src/spice-streaming-agent.cpp
> @@ -40,8 +40,6 @@
>
> using namespace spice::streaming_agent;
>
> -static size_t write_all(int fd, const void *buf, const size_t len);
> -
> static ConcreteAgent agent;
>
> namespace spice
> @@ -72,31 +70,44 @@ class Stream
> public:
> Stream(const char *name)
> {
> - fd = open(name, O_RDWR);
> - if (fd < 0) {
> + streamfd = open(name, O_RDWR);
> + if (streamfd < 0) {
is inside Stream, no reason to have a "streamfd" there, "fd" was fine.
> throw std::runtime_error("failed to open streaming device");
> }
> }
> ~Stream()
> {
> - close(fd);
> + close(streamfd);
> }
> - int file_descriptor() { return fd; }
> +
> + int read_command(bool blocking);
> + size_t write_all(const void *buf, const size_t len);
this should be private, maximum protected.
> + int send_format(unsigned w, unsigned h, uint8_t c);
> + int send_frame(const void *buf, const unsigned size);
> + void send_cursor(uint16_t width, uint16_t height,
> + uint16_t hotspot_x, uint16_t hotspot_y,
> + std::function<void(uint32_t *)> fill_cursor);
> +
> +private:
> + int have_something_to_read(int timeout);
> + void handle_stream_start_stop(uint32_t len);
> + void handle_stream_capabilities(uint32_t len);
> + void handle_stream_error(uint32_t len);
> + void read_command_from_device(void);
>
> private:
> - int fd = -1;
> + int streamfd = -1;
> + std::mutex mutex;
> };
>
> }} // namespace spice::streaming_agent
>
> -
spurious line removal, better to stick to 1 line spacing.
> static bool streaming_requested = false;
> static bool quit_requested = false;
> static bool log_binary = false;
> static std::set<SpiceVideoCodecType> client_codecs;
> -static std::mutex stream_mtx;
>
> -static int have_something_to_read(int streamfd, int timeout)
> +int Stream::have_something_to_read(int timeout)
> {
> struct pollfd pollfd = {streamfd, POLLIN, 0};
>
> @@ -112,7 +123,7 @@ static int have_something_to_read(int streamfd, int
> timeout)
> return 0;
> }
>
> -static void handle_stream_start_stop(int streamfd, uint32_t len)
> +void Stream::handle_stream_start_stop(uint32_t len)
> {
> uint8_t msg[256];
>
> @@ -134,7 +145,7 @@ static void handle_stream_start_stop(int streamfd,
> uint32_t len)
> }
> }
>
> -static void handle_stream_capabilities(int streamfd, uint32_t len)
> +void Stream::handle_stream_capabilities(uint32_t len)
> {
> uint8_t caps[STREAM_MSG_CAPABILITIES_MAX_BYTES];
>
> @@ -154,23 +165,23 @@ static void handle_stream_capabilities(int streamfd,
> uint32_t len)
> STREAM_TYPE_CAPABILITIES,
> 0
> };
> - if (write_all(streamfd, &hdr, sizeof(hdr)) != sizeof(hdr)) {
> + if (write_all(&hdr, sizeof(hdr)) != sizeof(hdr)) {
> throw std::runtime_error("error writing capabilities");
> }
> }
>
> -static void handle_stream_error(int streamfd, uint32_t len)
> +void Stream::handle_stream_error(uint32_t len)
> {
> // TODO read message and use it
> throw std::runtime_error("got an error message from server");
> }
>
> -static void read_command_from_device(int streamfd)
> +void Stream::read_command_from_device()
> {
> StreamDevHeader hdr;
> int n;
>
> - std::lock_guard<std::mutex> stream_guard(stream_mtx);
> + std::lock_guard<std::mutex> stream_guard(mutex);
> n = read(streamfd, &hdr, sizeof(hdr));
> if (n != sizeof(hdr)) {
> throw std::runtime_error("read command from device FAILED -- read "
> + std::to_string(n) +
> @@ -183,39 +194,38 @@ static void read_command_from_device(int streamfd)
>
> switch (hdr.type) {
> case STREAM_TYPE_CAPABILITIES:
> - return handle_stream_capabilities(streamfd, hdr.size);
> + return handle_stream_capabilities(hdr.size);
> case STREAM_TYPE_NOTIFY_ERROR:
> - return handle_stream_error(streamfd, hdr.size);
> + return handle_stream_error(hdr.size);
> case STREAM_TYPE_START_STOP:
> - return handle_stream_start_stop(streamfd, hdr.size);
> + return handle_stream_start_stop(hdr.size);
> }
> throw std::runtime_error("UNKNOWN msg of type " +
> std::to_string(hdr.type));
> }
>
> -static int read_command(int streamfd, bool blocking)
> +int Stream::read_command(bool blocking)
> {
> int timeout = blocking?-1:0;
> while (!quit_requested) {
> - if (!have_something_to_read(streamfd, timeout)) {
> + if (!have_something_to_read(timeout)) {
> if (!blocking) {
> return 0;
> }
> sleep(1);
> continue;
> }
> - read_command_from_device(streamfd);
> + read_command_from_device();
> break;
> }
>
> return 1;
> }
>
> -static size_t
> -write_all(int fd, const void *buf, const size_t len)
> +size_t Stream::write_all(const void *buf, const size_t len)
> {
> size_t written = 0;
> while (written < len) {
> - int l = write(fd, (const char *) buf + written, len - written);
> + int l = write(streamfd, (const char *) buf + written, len -
> written);
> if (l < 0) {
> if (errno == EINTR) {
> continue;
> @@ -229,7 +239,7 @@ write_all(int fd, const void *buf, const size_t len)
> return written;
> }
>
> -static int spice_stream_send_format(int streamfd, unsigned w, unsigned h,
> uint8_t c)
> +int Stream::send_format(unsigned w, unsigned h, uint8_t c)
> {
> const size_t msgsize = sizeof(FormatMessage);
> const size_t hdrsize = sizeof(StreamDevHeader);
> @@ -248,14 +258,14 @@ static int spice_stream_send_format(int streamfd,
> unsigned w, unsigned h, uint8_
> }
> };
> syslog(LOG_DEBUG, "writing format\n");
> - std::lock_guard<std::mutex> stream_guard(stream_mtx);
> - if (write_all(streamfd, &msg, msgsize) != msgsize) {
> + std::lock_guard<std::mutex> stream_guard(mutex);
> + if (write_all(&msg, msgsize) != msgsize) {
> return EXIT_FAILURE;
> }
> return EXIT_SUCCESS;
> }
>
> -static int spice_stream_send_frame(int streamfd, const void *buf, const
> unsigned size)
> +int Stream::send_frame(const void *buf, const unsigned size)
> {
> ssize_t n;
> const size_t msgsize = sizeof(FormatMessage);
> @@ -269,8 +279,8 @@ static int spice_stream_send_frame(int streamfd, const
> void *buf, const unsigned
> .msg = {}
> };
>
> - std::lock_guard<std::mutex> stream_guard(stream_mtx);
> - n = write_all(streamfd, &msg, msgsize);
> + std::lock_guard<std::mutex> stream_guard(mutex);
> + n = write_all(&msg, msgsize);
> syslog(LOG_DEBUG,
> "wrote %ld bytes of header of data msg with frame of size %u
> bytes\n",
> n, msg.hdr.size);
> @@ -279,7 +289,7 @@ static int spice_stream_send_frame(int streamfd, const
> void *buf, const unsigned
> n, msgsize);
> return EXIT_FAILURE;
> }
> - n = write_all(streamfd, buf, size);
> + n = write_all(buf, size);
> syslog(LOG_DEBUG, "wrote data msg body of size %ld\n", n);
> if (n != size) {
> syslog(LOG_WARNING, "write_all header: wrote %ld expected %u\n",
> @@ -333,11 +343,10 @@ static void usage(const char *progname)
> exit(1);
> }
>
> -static void
> -send_cursor(int streamfd,
> - uint16_t width, uint16_t height,
> - uint16_t hotspot_x, uint16_t hotspot_y,
> - std::function<void(uint32_t *)> fill_cursor)
> +void
> +Stream::send_cursor(uint16_t width, uint16_t height,
> + uint16_t hotspot_x, uint16_t hotspot_y,
> + std::function<void(uint32_t *)> fill_cursor)
> {
> if (width >= STREAM_MSG_CURSOR_SET_MAX_WIDTH || height >=
> STREAM_MSG_CURSOR_SET_MAX_HEIGHT) {
> return;
> @@ -370,11 +379,11 @@ send_cursor(int streamfd,
> uint32_t *pixels = reinterpret_cast<uint32_t *>(cursor_msg->msg.data);
> fill_cursor(pixels);
>
> - std::lock_guard<std::mutex> stream_guard(stream_mtx);
> - write_all(streamfd, storage.get(), msgsize);
> + std::lock_guard<std::mutex> stream_guard(mutex);
> + write_all(storage.get(), msgsize);
> }
>
> -static void cursor_changes(int streamfd, Display *display, int event_base)
> +static void cursor_changes(Stream *stream, Display *display, int event_base)
> {
> unsigned long last_serial = 0;
>
> @@ -399,18 +408,18 @@ static void cursor_changes(int streamfd, Display
> *display, int event_base)
> for (unsigned i = 0; i < cursor->width * cursor->height; ++i)
> pixels[i] = cursor->pixels[i];
> };
> - send_cursor(streamfd,
> - cursor->width, cursor->height, cursor->xhot,
> cursor->yhot, fill_cursor);
> + stream->send_cursor(cursor->width, cursor->height,
> + cursor->xhot, cursor->yhot, fill_cursor);
> }
> }
>
> static void
> -do_capture(int streamfd, const char *streamport, FILE *f_log)
> +do_capture(Stream &stream, const char *streamport, FILE *f_log)
> {
> unsigned int frame_count = 0;
> while (!quit_requested) {
> while (!quit_requested && !streaming_requested) {
> - if (read_command(streamfd, true) < 0) {
> + if (stream.read_command(true) < 0) {
> syslog(LOG_ERR, "FAILED to read command\n");
> return;
> }
> @@ -455,7 +464,7 @@ do_capture(int streamfd, const char *streamport, FILE
> *f_log)
>
> syslog(LOG_DEBUG, "wXh %uX%u codec=%u\n", width, height,
> codec);
>
> - if (spice_stream_send_format(streamfd, width, height, codec)
> == EXIT_FAILURE) {
> + if (stream.send_format(width, height, codec) ==
> EXIT_FAILURE) {
> throw std::runtime_error("FAILED to send format
> message");
> }
> }
> @@ -468,13 +477,12 @@ do_capture(int streamfd, const char *streamport, FILE
> *f_log)
> hexdump(frame.buffer, frame.buffer_size, f_log);
> }
> }
> - if (spice_stream_send_frame(streamfd,
> - frame.buffer, frame.buffer_size) ==
> EXIT_FAILURE) {
> + if (stream.send_frame(frame.buffer, frame.buffer_size) ==
> EXIT_FAILURE) {
> syslog(LOG_ERR, "FAILED to send a frame\n");
> break;
> }
> //usleep(1);
> - if (read_command(streamfd, false) < 0) {
> + if (stream.read_command(false) < 0) {
> syslog(LOG_ERR, "FAILED to read command\n");
> return;
> }
> @@ -576,12 +584,12 @@ int main(int argc, char* argv[])
> XFixesSelectCursorInput(display, rootwindow,
> XFixesDisplayCursorNotifyMask);
>
> Stream stream(streamport);
> - std::thread cursor_th(cursor_changes, stream.file_descriptor(), display,
> event_base);
> + std::thread cursor_th(cursor_changes, &stream, display, event_base);
> cursor_th.detach();
>
> int ret = EXIT_SUCCESS;
> try {
> - do_capture(stream.file_descriptor(), streamport, f_log);
> + do_capture(stream, streamport, f_log);
> }
> catch (std::runtime_error &err) {
> syslog(LOG_ERR, "%s\n", err.what());
Frediano
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