Here is V6 of my "Simple IPC" series. This version addresses comments from last week on V5. This includes: 1. Removing "perf and" in pkt-line.c 2. Better comments to describe the various timeout #define's. 3. Remove the double-underscore and shorten the "unix_stream_server" prefix. Thanks Jeff Jeff Hostetler (9): pkt-line: eliminate the need for static buffer in packet_write_gently() simple-ipc: design documentation for new IPC mechanism simple-ipc: add win32 implementation unix-socket: eliminate static unix_stream_socket() helper function unix-socket: add backlog size option to unix_stream_listen() unix-socket: disallow chdir() when creating unix domain sockets unix-stream-server: create unix domain socket under lock simple-ipc: add Unix domain socket implementation t0052: add simple-ipc tests and t/helper/test-simple-ipc tool Johannes Schindelin (3): pkt-line: do not issue flush packets in write_packetized_*() pkt-line: add PACKET_READ_GENTLE_ON_READ_ERROR option pkt-line: add options argument to read_packetized_to_strbuf() Documentation/technical/api-simple-ipc.txt | 105 ++ Makefile | 9 + builtin/credential-cache--daemon.c | 3 +- builtin/credential-cache.c | 2 +- compat/simple-ipc/ipc-shared.c | 28 + compat/simple-ipc/ipc-unix-socket.c | 1000 ++++++++++++++++++++ compat/simple-ipc/ipc-win32.c | 751 +++++++++++++++ config.mak.uname | 2 + contrib/buildsystems/CMakeLists.txt | 8 +- convert.c | 11 +- pkt-line.c | 59 +- pkt-line.h | 17 +- simple-ipc.h | 239 +++++ t/helper/test-simple-ipc.c | 787 +++++++++++++++ t/helper/test-tool.c | 1 + t/helper/test-tool.h | 1 + t/t0052-simple-ipc.sh | 122 +++ unix-socket.c | 53 +- unix-socket.h | 12 +- unix-stream-server.c | 125 +++ unix-stream-server.h | 33 + 21 files changed, 3316 insertions(+), 52 deletions(-) create mode 100644 Documentation/technical/api-simple-ipc.txt create mode 100644 compat/simple-ipc/ipc-shared.c create mode 100644 compat/simple-ipc/ipc-unix-socket.c create mode 100644 compat/simple-ipc/ipc-win32.c create mode 100644 simple-ipc.h create mode 100644 t/helper/test-simple-ipc.c create mode 100755 t/t0052-simple-ipc.sh create mode 100644 unix-stream-server.c create mode 100644 unix-stream-server.h base-commit: f01623b2c9d14207e497b21ebc6b3ec4afaf4b46 Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-766%2Fjeffhostetler%2Fsimple-ipc-v6 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-766/jeffhostetler/simple-ipc-v6 Pull-Request: https://github.com/gitgitgadget/git/pull/766 Range-diff vs v5: 1: 311ea4a5cd71 ! 1: fe35dc3d292d pkt-line: eliminate the need for static buffer in packet_write_gently() @@ pkt-line.c: int packet_write_fmt_gently(int fd, const char *fmt, ...) + set_packet_header(header, packet_size); + + /* -+ * Write the header and the buffer in 2 parts so that we do not need -+ * to allocate a buffer or rely on a static buffer. This avoids perf -+ * and multi-threading issues. ++ * Write the header and the buffer in 2 parts so that we do ++ * not need to allocate a buffer or rely on a static buffer. ++ * This also avoids putting a large buffer on the stack which ++ * might have multi-threading issues. + */ + + if (write_in_full(fd_out, header, 4) < 0 || 2: 25157c1f4873 = 2: de11b3036148 pkt-line: do not issue flush packets in write_packetized_*() 3: af3d13113bc9 = 3: 3718da39da30 pkt-line: add PACKET_READ_GENTLE_ON_READ_ERROR option 4: b73e66a69b61 = 4: b43df7ad0b7a pkt-line: add options argument to read_packetized_to_strbuf() 5: 1ae99d824a21 = 5: f829feb2aa93 simple-ipc: design documentation for new IPC mechanism 6: 8b3ce40e4538 = 6: 58c3fb7cd776 simple-ipc: add win32 implementation 7: 34df1af98e5b = 7: 4e8c352fb366 unix-socket: eliminate static unix_stream_socket() helper function 8: d6ff6e0e050a = 8: 3b71f52d8628 unix-socket: add backlog size option to unix_stream_listen() 9: 21b8d3c63dbf = 9: 5972a198361c unix-socket: disallow chdir() when creating unix domain sockets 10: 1ee9de55a106 ! 10: 02c885fd623d unix-stream-server: create unix domain socket under lock @@ unix-stream-server.c (new) + return 0; +} + -+int unix_stream_server__create( -+ const char *path, -+ const struct unix_stream_listen_opts *opts, -+ long timeout_ms, -+ struct unix_stream_server_socket **new_server_socket) ++int unix_ss_create(const char *path, ++ const struct unix_stream_listen_opts *opts, ++ long timeout_ms, ++ struct unix_ss_socket **new_server_socket) +{ + struct lock_file lock = LOCK_INIT; + int fd_socket; -+ struct unix_stream_server_socket *server_socket; ++ struct unix_ss_socket *server_socket; + + *new_server_socket = NULL; + @@ unix-stream-server.c (new) + return 0; +} + -+void unix_stream_server__free( -+ struct unix_stream_server_socket *server_socket) ++void unix_ss_free(struct unix_ss_socket *server_socket) +{ + if (!server_socket) + return; + + if (server_socket->fd_socket >= 0) { -+ if (!unix_stream_server__was_stolen(server_socket)) ++ if (!unix_ss_was_stolen(server_socket)) + unlink(server_socket->path_socket); + close(server_socket->fd_socket); + } @@ unix-stream-server.c (new) + free(server_socket); +} + -+int unix_stream_server__was_stolen( -+ struct unix_stream_server_socket *server_socket) ++int unix_ss_was_stolen(struct unix_ss_socket *server_socket) +{ + struct stat st_now; + @@ unix-stream-server.h (new) + +#include "unix-socket.h" + -+struct unix_stream_server_socket { ++struct unix_ss_socket { + char *path_socket; + struct stat st_socket; + int fd_socket; @@ unix-stream-server.h (new) + * + * Returns 0 on success, -1 on error, -2 if socket is in use. + */ -+int unix_stream_server__create( -+ const char *path, -+ const struct unix_stream_listen_opts *opts, -+ long timeout_ms, -+ struct unix_stream_server_socket **server_socket); ++int unix_ss_create(const char *path, ++ const struct unix_stream_listen_opts *opts, ++ long timeout_ms, ++ struct unix_ss_socket **server_socket); + +/* + * Close and delete the socket. + */ -+void unix_stream_server__free( -+ struct unix_stream_server_socket *server_socket); ++void unix_ss_free(struct unix_ss_socket *server_socket); + +/* + * Return 1 if the inode of the pathname to our socket changes. + */ -+int unix_stream_server__was_stolen( -+ struct unix_stream_server_socket *server_socket); ++int unix_ss_was_stolen(struct unix_ss_socket *server_socket); + +#endif /* UNIX_STREAM_SERVER_H */ 11: f2e3b046cc8f ! 11: 4c2199231d05 simple-ipc: add Unix domain socket implementation @@ compat/simple-ipc/ipc-unix-socket.c (new) +} + +/* -+ * This value was chosen at random. ++ * Retry frequency when trying to connect to a server. ++ * ++ * This value should be short enough that we don't seriously delay our ++ * caller, but not fast enough that our spinning puts pressure on the ++ * system. + */ +#define WAIT_STEP_MS (50) + @@ compat/simple-ipc/ipc-unix-socket.c (new) + const struct ipc_client_connect_options *options, + int *pfd) +{ -+ int wait_ms = 50; + int k; + + *pfd = -1; + -+ for (k = 0; k < timeout_ms; k += wait_ms) { ++ for (k = 0; k < timeout_ms; k += WAIT_STEP_MS) { + int fd = unix_stream_connect(path, options->uds_disallow_chdir); + + if (fd != -1) { @@ compat/simple-ipc/ipc-unix-socket.c (new) + return IPC_STATE__OTHER_ERROR; + + sleep_and_try_again: -+ sleep_millisec(wait_ms); ++ sleep_millisec(WAIT_STEP_MS); + } + + return IPC_STATE__NOT_LISTENING; +} + +/* -+ * A randomly chosen timeout value. ++ * The total amount of time that we are willing to wait when trying to ++ * connect to a server. ++ * ++ * When the server is first started, it might take a little while for ++ * it to become ready to service requests. Likewise, the server may ++ * be very (temporarily) busy and not respond to our connections. ++ * ++ * We should gracefully and silently handle those conditions and try ++ * again for a reasonable time period. ++ * ++ * The value chosen here should be long enough for the server ++ * to reliably heal from the above conditions. + */ +#define MY_CONNECTION_TIMEOUT_MS (1000) + @@ compat/simple-ipc/ipc-unix-socket.c (new) + enum magic magic; + struct ipc_server_data *server_data; + -+ struct unix_stream_server_socket *server_socket; ++ struct unix_ss_socket *server_socket; + + int fd_send_shutdown; + int fd_wait_shutdown; @@ compat/simple-ipc/ipc-unix-socket.c (new) + * will be routed elsewhere and we silently starve. + * If that happens, just queue a shutdown. + */ -+ if (unix_stream_server__was_stolen( ++ if (unix_ss_was_stolen( + accept_thread_data->server_socket)) { + trace2_data_string("ipc-accept", NULL, + "queue_stop_async", @@ compat/simple-ipc/ipc-unix-socket.c (new) +static int create_listener_socket( + const char *path, + const struct ipc_server_opts *ipc_opts, -+ struct unix_stream_server_socket **new_server_socket) ++ struct unix_ss_socket **new_server_socket) +{ -+ struct unix_stream_server_socket *server_socket = NULL; ++ struct unix_ss_socket *server_socket = NULL; + struct unix_stream_listen_opts uslg_opts = UNIX_STREAM_LISTEN_OPTS_INIT; + int ret; + + uslg_opts.listen_backlog_size = LISTEN_BACKLOG; + uslg_opts.disallow_chdir = ipc_opts->uds_disallow_chdir; + -+ ret = unix_stream_server__create(path, &uslg_opts, -1, &server_socket); ++ ret = unix_ss_create(path, &uslg_opts, -1, &server_socket); + if (ret) + return ret; + + if (set_socket_blocking_flag(server_socket->fd_socket, 1)) { + int saved_errno = errno; -+ unix_stream_server__free(server_socket); ++ unix_ss_free(server_socket); + errno = saved_errno; + return -1; + } @@ compat/simple-ipc/ipc-unix-socket.c (new) +static int setup_listener_socket( + const char *path, + const struct ipc_server_opts *ipc_opts, -+ struct unix_stream_server_socket **new_server_socket) ++ struct unix_ss_socket **new_server_socket) +{ + int ret, saved_errno; + @@ compat/simple-ipc/ipc-unix-socket.c (new) + ipc_server_application_cb *application_cb, + void *application_data) +{ -+ struct unix_stream_server_socket *server_socket = NULL; ++ struct unix_ss_socket *server_socket = NULL; + struct ipc_server_data *server_data; + int sv[2]; + int k; @@ compat/simple-ipc/ipc-unix-socket.c (new) + + accept_thread_data = server_data->accept_thread; + if (accept_thread_data) { -+ unix_stream_server__free(accept_thread_data->server_socket); ++ unix_ss_free(accept_thread_data->server_socket); + + if (accept_thread_data->fd_send_shutdown != -1) + close(accept_thread_data->fd_send_shutdown); 12: 6ccc7472096f = 12: 132b6f3271be t0052: add simple-ipc tests and t/helper/test-simple-ipc tool -- gitgitgadget