diff options
| -rw-r--r-- | src/gammad.c | 261 |
1 files changed, 196 insertions, 65 deletions
diff --git a/src/gammad.c b/src/gammad.c index 6dcb31f..7dfebd9 100644 --- a/src/gammad.c +++ b/src/gammad.c @@ -38,6 +38,14 @@ /** + * Number put in front of the marshalled data + * so the program an detect incompatible updates + */ +#define MARSHAL_VERSION 0 + + + +/** * The name of the process */ char* argv0; @@ -87,6 +95,16 @@ int gerror; int init_stage = 0; /** + * The adjustment method, -1 for automatic + */ +int method = -1; + +/** + * The site's name, may be `NULL` + */ +char* sitename = NULL; + +/** * The libgamma site state */ libgamma_site_state_t site; @@ -228,6 +246,17 @@ static inline char* get_pidfile_pathname(void) /** + * Get the pathname of the state file + * + * @return The pathname of the state file, `NULL` on error + */ +static inline char* get_state_pathname(void) +{ + return get_pathname(".state"); +} + + +/** * Parse adjustment method name (or stringised number) * * @param arg The adjustment method name (or stringised number) @@ -463,8 +492,8 @@ static int create_pidfile(char* pidfile) /** * Initialise the process * - * @param method The adjustment method, -1 for automatic - * @param sitename The site's name, may be `NULL` + * @param full Perform a full initialisation, shall be done + * iff the state is not going to be unmarshalled * @param preserve Preserve current gamma ramps at priority 0 * @param foreground Keep process in the foreground * @param keep_stderr Keep stderr open @@ -475,7 +504,7 @@ static int create_pidfile(char* pidfile) * Otherwise: The negative of the exit value the * process should have and shall exit immediately */ -static int initialise(int method, const char *sitename, int preserve, int foreground, int keep_stderr) +static int initialise(int full, int preserve, int foreground, int keep_stderr) { struct sockaddr_un address; struct rlimit rlimit; @@ -487,22 +516,25 @@ static int initialise(int method, const char *sitename, int preserve, int foregr /* Zero out some memory so it can be destoried safely. */ memset(&site, 0, sizeof(site)); - /* Close all file descriptors above stderr */ - if (getrlimit(RLIMIT_NOFILE, &rlimit) || (rlimit.rlim_cur == RLIM_INFINITY)) - n = 4 << 10; - else - n = (size_t)(rlimit.rlim_cur); - for (i = STDERR_FILENO + 1; i < n; i++) - close((int)i); - - /* Set umask, reset signal handlers, and reset signal mask */ - umask(0); - for (r = 1; r < _NSIG; r++) - signal(r, SIG_DFL); - if (sigfillset(&mask)) - perror(argv0); - else - sigprocmask(SIG_UNBLOCK, &mask, NULL); + if (full) + { + /* Close all file descriptors above stderr */ + if (getrlimit(RLIMIT_NOFILE, &rlimit) || (rlimit.rlim_cur == RLIM_INFINITY)) + n = 4 << 10; + else + n = (size_t)(rlimit.rlim_cur); + for (i = STDERR_FILENO + 1; i < n; i++) + close((int)i); + + /* Set umask, reset signal handlers, and reset signal mask */ + umask(0); + for (r = 1; r < _NSIG; r++) + signal(r, SIG_DFL); + if (sigfillset(&mask)) + perror(argv0); + else + sigprocmask(SIG_UNBLOCK, &mask, NULL); + } /* Get method */ if ((method < 0) && (libgamma_list_methods(&method, 1, 0) < 1)) @@ -515,19 +547,22 @@ static int initialise(int method, const char *sitename, int preserve, int foregr if ((gerror = libgamma_site_initialise(&site, method, sitename_dup))) goto fail_libgamma; - /* Get PID file and socket pathname */ - if (!(pidpath = get_pidfile_pathname())) - goto fail; - if (!(socketpath = get_socket_pathname())) - goto fail; - - /* Create PID file */ - if ((r = create_pidfile(pidpath)) < 0) + if (full) { - free(pidpath), pidpath = NULL; - if (r == -2) - goto already_running; - goto fail; + /* Get PID file and socket pathname */ + if (!(pidpath = get_pidfile_pathname())) + goto fail; + if (!(socketpath = get_socket_pathname())) + goto fail; + + /* Create PID file */ + if ((r = create_pidfile(pidpath)) < 0) + { + free(pidpath), pidpath = NULL; + if (r == -2) + goto already_running; + goto fail; + } } /* Get partitions */ @@ -662,33 +697,36 @@ static int initialise(int method, const char *sitename, int preserve, int foregr goto fail; } - /* Create socket and start listening */ - address.sun_family = AF_UNIX; - if (strlen(socketpath) >= sizeof(address.sun_path)) + if (full) { - errno = ENAMETOOLONG; - goto fail; + /* Create socket and start listening */ + address.sun_family = AF_UNIX; + if (strlen(socketpath) >= sizeof(address.sun_path)) + { + errno = ENAMETOOLONG; + goto fail; + } + strcpy(address.sun_path, socketpath); + unlink(socketpath); + if ((socketfd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) + goto fail; + if (fchmod(socketfd, S_IRWXU) < 0) + goto fail; + if (bind(socketfd, (struct sockaddr*)(&address), sizeof(address)) < 0) + goto fail; + if (listen(socketfd, SOMAXCONN) < 0) + goto fail; + + /* Get the real pathname of the process's binary, in case + * it is relative, so we can re-execute without problem. */ + if ((*argv0 != '/') && strchr(argv0, '/')) + if (!(argv0_real = realpath(argv0, NULL))) + goto fail; + + /* Change directory to / to avoid blocking umounting */ + if (chdir("/") < 0) + perror(argv0); } - strcpy(address.sun_path, socketpath); - unlink(socketpath); - if ((socketfd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) - goto fail; - if (fchmod(socketfd, S_IRWXU) < 0) - goto fail; - if (bind(socketfd, (struct sockaddr*)(&address), sizeof(address)) < 0) - goto fail; - if (listen(socketfd, SOMAXCONN) < 0) - goto fail; - - /* Get the real pathname of the process's binary, in case - * it is relative, so we can re-execute without problem. */ - if ((*argv0 != '/') && strchr(argv0, '/')) - if (!(argv0_real = realpath(argv0, NULL))) - goto fail; - - /* Change directory to / to avoid blocking umounting */ - if (chdir("/") < 0) - perror(argv0); /* Set up signal handlers */ if (signal(SIGUSR1, sig_reexec) == SIG_ERR) @@ -696,13 +734,16 @@ static int initialise(int method, const char *sitename, int preserve, int foregr if (signal(SIGTERM, sig_terminate) == SIG_ERR) goto fail; - /* Initialise the server */ - if (server_initialise() < 0) - goto fail; - init_stage++; + if (full) + { + /* Initialise the server */ + if (server_initialise() < 0) + goto fail; + init_stage++; + } /* Place in the background unless -f */ - if (foreground == 0) + if (full && (foreground == 0)) { pid_t pid; int fd = -1, saved_errno; @@ -783,7 +824,7 @@ static int initialise(int method, const char *sitename, int preserve, int foregr errno = saved_errno; done_background:; } - else + else if (full) { /* Signal the spawner that the service is ready */ close(STDOUT_FILENO); @@ -873,6 +914,84 @@ static void destroy(void) unlink(pidpath); free(pidpath); free(argv0_real); + free(sitename); +} + + +/** + * Marshal the state of the process + * + * @param buf Output buffer for the marshalled data, + * `NULL` to only measure how large the + * buffer needs to be + * @return The number of marshalled news + */ +static size_t marshal(void* buf) +{ + size_t off = 0, i, n; + char* bs = buf; + + if (bs != NULL) + *(int*)(bs + off) = MARSHAL_VERSION; + off += sizeof(int); + + if (argv0_real == NULL) + { + if (bs != NULL) + *(bs + off) = '\0'; + off += 1; + } + else + { + n = strlen(argv0_real) + 1; + if (bs != NULL) + memcpy(bs + off, argv0_real, n); + off += n; + } + + if (bs != NULL) + *(size_t*)(bs + off) = outputs_n; + off += sizeof(size_t); + + for (i = 0; i < outputs_n; i++) + off += output_marshal(outputs + i , bs ? bs + off : NULL); + + if (bs != NULL) + *(int*)(bs + off) = socketfd; + off += sizeof(int); + + n = strlen(pidpath) + 1; + if (bs != NULL) + memcpy(bs + off, pidpath, n); + off += n; + + n = strlen(socketpath) + 1; + if (bs != NULL) + memcpy(bs + off, socketpath, n); + off += n; + + off += server_marshal(bs ? bs + off : NULL); + + if (bs != NULL) + *(int*)(bs + off) = init_stage; + off += sizeof(int); + + if (bs != NULL) + *(int*)(bs + off) = method; + off += sizeof(int); + + if (bs != NULL) + *(int*)(bs + off) = sitename != NULL; + off += sizeof(int); + if (sitename != NULL) + { + n = strlen(sitename) + 1; + if (bs != NULL) + memcpy(bs + off, sitename, n); + off += n; + } + + return off; } @@ -915,13 +1034,17 @@ static void usage(void) */ int main(int argc, char** argv) { - int method = -1, rc = 1, preserve = 0, foreground = 0, keep_stderr = 0, r; - char* sitename = NULL; + int rc = 1, preserve = 0, foreground = 0, keep_stderr = 0, r; + char* statefile = NULL; ARGBEGIN { case 's': sitename = EARGF(usage()); + /* To simplify re-exec: */ + sitename = memdup(sitename, strlen(sitename) + 1); + if (sitename == NULL) + goto fail; break; case 'm': method = get_method(EARGF(usage())); @@ -937,6 +1060,9 @@ int main(int argc, char** argv) case 'k': keep_stderr = 1; break; + case '#': /* Internal, do not document */ + statefile = EARGF(usage()); + break; default: usage(); } @@ -944,7 +1070,7 @@ int main(int argc, char** argv) if (argc > 0) usage(); - switch ((r = initialise(method, sitename, preserve, foreground, keep_stderr))) + switch ((r = initialise(statefile == NULL, preserve, foreground, keep_stderr))) { case 1: break; @@ -959,6 +1085,11 @@ int main(int argc, char** argv) return -r; } + if (statefile != NULL) + { + /* TODO unmarshal */ + } + rc = 0; done: destroy(); |