From 00d76784f42408bdf46a8b1e753536f033fd9e08 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= Date: Wed, 5 Feb 2020 19:53:50 +0100 Subject: [PATCH] main: add --print-pid=FILE|FD When specified, our PID is written to the specified file (or FD), after we've successfully started up. Only applicable in server mode. --- completions/zsh/_foot | 1 + doc/foot.1.scd | 7 ++++ main.c | 75 +++++++++++++++++++++++++++++++++++++------ 3 files changed, 73 insertions(+), 10 deletions(-) diff --git a/completions/zsh/_foot b/completions/zsh/_foot index 8fbec2bd..3b068f7f 100644 --- a/completions/zsh/_foot +++ b/completions/zsh/_foot @@ -8,6 +8,7 @@ _arguments \ '(-g --geometry)'{-g,--geometry}'[window WIDTHxHEIGHT, in pixels (80x24 cells)]:geometry:()' \ '(-s --server)'{-s,--server}'[run as server; open terminals by running footclient]:server:_files' \ '--hold[remain open after child process exits]' \ + '(-p --print-pid)'{-p,--print-pid}'[print PID to this file or FD when up and running (server mode only)]:pidfile:_files' \ '(-v --version)'{-v,--version}'[show the version number and quit]' \ '(-h --help)'{-h,--help}'[show help message and quit]' diff --git a/doc/foot.1.scd b/doc/foot.1.scd index 0cb1235c..b555ba90 100644 --- a/doc/foot.1.scd +++ b/doc/foot.1.scd @@ -65,6 +65,13 @@ execute (instead of the shell). *--hold* Remain open after child process exits. +*-p*,*--print-pid*=_FILE_|_FD_ + Print PID to this file, or FD, when successfully started. The file + (or FD) is closed immediately after writing the PID. When a _FILE_ + as been specified, the file is unlinked when yambar exits. + + This option can only be used in combination with *-s*,*--server*. + *-v*,*--version* Show the version number and quit. diff --git a/main.c b/main.c index ba13ea93..0c127e84 100644 --- a/main.c +++ b/main.c @@ -9,7 +9,9 @@ #include #include +#include #include +#include #include @@ -41,14 +43,15 @@ print_usage(const char *prog_name) "Usage: %s [OPTIONS]... -- command\n" "\n" "Options:\n" - " -c,--config=PATH load configuration from PATH (XDG_CONFIG_HOME/footrc)\n" - " -f,--font=FONT comma separated list of fonts in fontconfig format (monospace)\n" - " -t,--term=TERM value to set the environment variable TERM to (foot)\n" - " -g,--geometry=WIDTHxHEIGHT set initial width and height\n" - " -s,--server[=PATH] run as a server (use 'footclient' to start terminals).\n" - " Without PATH, XDG_RUNTIME_DIR/foot.sock will be used.\n" - " --hold remain open after child process exits\n" - " -v,--version show the version number and quit\n", + " -c,--config=PATH load configuration from PATH (XDG_CONFIG_HOME/footrc)\n" + " -f,--font=FONT comma separated list of fonts in fontconfig format (monospace)\n" + " -t,--term=TERM value to set the environment variable TERM to (foot)\n" + " -g,--geometry=WIDTHxHEIGHT set initial width and height\n" + " -s,--server[=PATH] run as a server (use 'footclient' to start terminals).\n" + " Without PATH, XDG_RUNTIME_DIR/foot.sock will be used.\n" + " --hold remain open after child process exits\n" + " -p,--print-pid=FILE|FD print PID to file or FD (only applicable in server mode)\n" + " -v,--version show the version number and quit\n", prog_name, prog_name); } @@ -80,6 +83,43 @@ term_shutdown_cb(void *data, int exit_code) ctx->exit_code = exit_code; } +static bool +print_pid(const char *pid_file, bool *unlink_at_exit) +{ + LOG_DBG("printing PID to %s", pid_file); + + errno = 0; + char *end; + int pid_fd = strtoul(pid_file, &end, 10); + + if (errno != 0 || *end != '\0') { + if ((pid_fd = open(pid_file, + O_WRONLY | O_CREAT | O_EXCL | O_CLOEXEC, + S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)) < 0) { + LOG_ERRNO("%s: failed to open", pid_file); + return false; + } else + *unlink_at_exit = true; + } + + if (pid_fd >= 0) { + char pid[32]; + snprintf(pid, sizeof(pid), "%u\n", getpid()); + + ssize_t bytes = write(pid_fd, pid, strlen(pid)); + close(pid_fd); + + if (bytes < 0) { + LOG_ERRNO("failed to write PID to FD=%u", pid_fd); + return false; + } + + LOG_DBG("wrote %zd bytes to FD=%d", bytes, pid_fd); + return true; + } else + return false; +} + int main(int argc, char *const *argv) { @@ -98,7 +138,8 @@ main(int argc, char *const *argv) {"geometry", required_argument, NULL, 'g'}, {"server", optional_argument, NULL, 's'}, {"hold", no_argument, NULL, 'H'}, - {"presentation-timings", no_argument, NULL, 'p'}, /* Undocumented */ + {"presentation-timings", no_argument, NULL, 'P'}, /* Undocumented */ + {"print-pid", required_argument, NULL, 'p'}, {"version", no_argument, NULL, 'v'}, {"help", no_argument, NULL, 'h'}, {NULL, no_argument, NULL, 0}, @@ -113,6 +154,8 @@ main(int argc, char *const *argv) const char *conf_server_socket_path = NULL; bool presentation_timings = false; bool hold = false; + bool unlink_pid_file = false; + const char *pid_file = NULL; while (true) { int c = getopt_long(argc, argv, "c:tf:g:s::pvh", longopts, NULL); @@ -168,7 +211,7 @@ main(int argc, char *const *argv) conf_server_socket_path = optarg; break; - case 'p': + case 'P': presentation_timings = true; break; @@ -176,6 +219,10 @@ main(int argc, char *const *argv) hold = true; break; + case 'p': + pid_file = optarg; + break; + case 'v': printf("foot version %s\n", FOOT_VERSION); return EXIT_SUCCESS; @@ -277,6 +324,11 @@ main(int argc, char *const *argv) if (as_server) LOG_INFO("running as server; launch terminals by running footclient"); + if (as_server && pid_file != NULL) { + if (!print_pid(pid_file, &unlink_pid_file)) + goto out; + } + while (!aborted && (as_server || tll_length(wayl->terms) > 0)) { if (!fdm_poll(fdm)) break; @@ -295,6 +347,9 @@ out: config_free(conf); + if (unlink_pid_file) + unlink(pid_file); + LOG_INFO("goodbye"); log_deinit(); return ret == EXIT_SUCCESS && !as_server ? shutdown_ctx.exit_code : ret;