From: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx> Create client routines to spawn a fsmonitor daemon and send it an IPC request using `simple-ipc`. Signed-off-by: Jeff Hostetler <jeffhost@xxxxxxxxxxxxx> --- Makefile | 1 + fsmonitor-ipc.c | 153 ++++++++++++++++++++++++++++++++++++++++++++++++ fsmonitor-ipc.h | 48 +++++++++++++++ help.c | 4 ++ 4 files changed, 206 insertions(+) create mode 100644 fsmonitor-ipc.c create mode 100644 fsmonitor-ipc.h diff --git a/Makefile b/Makefile index a6a73c574191..50977911d41a 100644 --- a/Makefile +++ b/Makefile @@ -891,6 +891,7 @@ LIB_OBJS += fetch-pack.o LIB_OBJS += fmt-merge-msg.o LIB_OBJS += fsck.o LIB_OBJS += fsmonitor.o +LIB_OBJS += fsmonitor-ipc.o LIB_OBJS += gettext.o LIB_OBJS += gpg-interface.o LIB_OBJS += graph.o diff --git a/fsmonitor-ipc.c b/fsmonitor-ipc.c new file mode 100644 index 000000000000..b0dc334ff02d --- /dev/null +++ b/fsmonitor-ipc.c @@ -0,0 +1,153 @@ +#include "cache.h" +#include "fsmonitor.h" +#include "fsmonitor-ipc.h" +#include "run-command.h" +#include "strbuf.h" +#include "trace2.h" + +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND +#define FSMONITOR_DAEMON_IS_SUPPORTED 1 +#else +#define FSMONITOR_DAEMON_IS_SUPPORTED 0 +#endif + +/* + * A trivial function so that this source file always defines at least + * one symbol even when the feature is not supported. This quiets an + * annoying compiler error. + */ +int fsmonitor_ipc__is_supported(void) +{ + return FSMONITOR_DAEMON_IS_SUPPORTED; +} + +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND + +GIT_PATH_FUNC(fsmonitor_ipc__get_path, "fsmonitor") + +enum ipc_active_state fsmonitor_ipc__get_state(void) +{ + return ipc_get_active_state(fsmonitor_ipc__get_path()); +} + +static int spawn_daemon(void) +{ + const char *args[] = { "fsmonitor--daemon", "--start", NULL }; + + return run_command_v_opt_tr2(args, RUN_COMMAND_NO_STDIN | RUN_GIT_CMD, + "fsmonitor"); +} + +int fsmonitor_ipc__send_query(const char *since_token, + struct strbuf *answer) +{ + int ret = -1; + int tried_to_spawn = 0; + enum ipc_active_state state = IPC_STATE__OTHER_ERROR; + struct ipc_client_connection *connection = NULL; + struct ipc_client_connect_options options + = IPC_CLIENT_CONNECT_OPTIONS_INIT; + + options.wait_if_busy = 1; + options.wait_if_not_found = 0; + + trace2_region_enter("fsm_client", "query", NULL); + + trace2_data_string("fsm_client", NULL, "query/command", + since_token); + +try_again: + state = ipc_client_try_connect(fsmonitor_ipc__get_path(), &options, + &connection); + + switch (state) { + case IPC_STATE__LISTENING: + ret = ipc_client_send_command_to_connection( + connection, since_token, answer); + ipc_client_close_connection(connection); + + trace2_data_intmax("fsm_client", NULL, + "query/response-length", answer->len); + + if (fsmonitor_is_trivial_response(answer)) + trace2_data_intmax("fsm_client", NULL, + "query/trivial-response", 1); + + goto done; + + case IPC_STATE__NOT_LISTENING: + ret = error(_("fsmonitor_ipc__send_query: daemon not available")); + goto done; + + case IPC_STATE__PATH_NOT_FOUND: + if (tried_to_spawn) + goto done; + + tried_to_spawn++; + if (spawn_daemon()) + goto done; + + /* + * Try again, but this time give the daemon a chance to + * actually create the pipe/socket. + * + * Granted, the daemon just started so it can't possibly have + * any FS cached yet, so we'll always get a trivial answer. + * BUT the answer should include a new token that can serve + * as the basis for subsequent requests. + */ + options.wait_if_not_found = 1; + goto try_again; + + case IPC_STATE__INVALID_PATH: + ret = error(_("fsmonitor_ipc__send_query: invalid path '%s'"), + fsmonitor_ipc__get_path()); + goto done; + + case IPC_STATE__OTHER_ERROR: + default: + ret = error(_("fsmonitor_ipc__send_query: unspecified error on '%s'"), + fsmonitor_ipc__get_path()); + goto done; + } + +done: + trace2_region_leave("fsm_client", "query", NULL); + + return ret; +} + +int fsmonitor_ipc__send_command(const char *command, + struct strbuf *answer) +{ + struct ipc_client_connection *connection = NULL; + struct ipc_client_connect_options options + = IPC_CLIENT_CONNECT_OPTIONS_INIT; + int ret; + enum ipc_active_state state; + + strbuf_reset(answer); + + options.wait_if_busy = 1; + options.wait_if_not_found = 0; + + state = ipc_client_try_connect(fsmonitor_ipc__get_path(), &options, + &connection); + if (state != IPC_STATE__LISTENING) { + die("fsmonitor--daemon is not running"); + return -1; + } + + ret = ipc_client_send_command_to_connection(connection, command, answer); + ipc_client_close_connection(connection); + + if (ret == -1) { + die("could not send '%s' command to fsmonitor--daemon", + command); + return -1; + } + + return 0; +} + +#endif diff --git a/fsmonitor-ipc.h b/fsmonitor-ipc.h new file mode 100644 index 000000000000..7d21c1260151 --- /dev/null +++ b/fsmonitor-ipc.h @@ -0,0 +1,48 @@ +#ifndef FSMONITOR_IPC_H +#define FSMONITOR_IPC_H + +/* + * Returns true if a filesystem notification backend is defined + * for this platform. This symbol must always be visible and + * outside of the HAVE_ ifdef. + */ +int fsmonitor_ipc__is_supported(void); + +#ifdef HAVE_FSMONITOR_DAEMON_BACKEND +#include "run-command.h" +#include "simple-ipc.h" + +/* + * Returns the pathname to the IPC named pipe or Unix domain socket + * where a `git-fsmonitor--daemon` process will listen. This is a + * per-worktree value. + */ +const char *fsmonitor_ipc__get_path(void); + +/* + * Try to determine whether there is a `git-fsmonitor--daemon` process + * listening on the IPC pipe/socket. + */ +enum ipc_active_state fsmonitor_ipc__get_state(void); + +/* + * Connect to a `git-fsmonitor--daemon` process via simple-ipc + * and ask for the set of changed files since the given token. + * + * This DOES NOT use the hook interface. + * + * Spawn a daemon process in the background if necessary. + */ +int fsmonitor_ipc__send_query(const char *since_token, + struct strbuf *answer); + +/* + * Connect to a `git-fsmonitor--daemon` process via simple-ipc and + * send a command verb. If no daemon is available, we DO NOT try to + * start one. + */ +int fsmonitor_ipc__send_command(const char *command, + struct strbuf *answer); + +#endif /* HAVE_FSMONITOR_DAEMON_BACKEND */ +#endif /* FSMONITOR_IPC_H */ diff --git a/help.c b/help.c index 3c3bdec21356..e22ba1d246a5 100644 --- a/help.c +++ b/help.c @@ -11,6 +11,7 @@ #include "version.h" #include "refs.h" #include "parse-options.h" +#include "fsmonitor-ipc.h" struct category_description { uint32_t category; @@ -664,6 +665,9 @@ void get_version_info(struct strbuf *buf, int show_build_options) strbuf_addf(buf, "sizeof-size_t: %d\n", (int)sizeof(size_t)); strbuf_addf(buf, "shell-path: %s\n", SHELL_PATH); /* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */ + + if (fsmonitor_ipc__is_supported()) + strbuf_addstr(buf, "feature: fsmonitor--daemon\n"); } } -- gitgitgadget