diff options
Diffstat (limited to 'src/coopgammad.c')
| -rw-r--r-- | src/coopgammad.c | 1335 |
1 files changed, 1335 insertions, 0 deletions
diff --git a/src/coopgammad.c b/src/coopgammad.c new file mode 100644 index 0000000..26a9d05 --- /dev/null +++ b/src/coopgammad.c @@ -0,0 +1,1335 @@ +/** + * coopgammad -- Cooperative gamma server + * Copyright (C) 2016 Mattias Andrée (maandree@kth.se) + * + * This library is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this library. If not, see <http://www.gnu.org/licenses/>. + */ +#include <libgamma.h> + +#include <sys/resource.h> +#include <sys/socket.h> +#include <sys/stat.h> +#include <sys/un.h> +#include <errno.h> +#include <fcntl.h> +#include <pwd.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "arg.h" +#include "output.h" +#include "util.h" +#include "server.h" + + + +/** + * 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; + +/** + * The real pathname of the process's binary, + * `NULL` if `argv0` is satisfactory + */ +char* argv0_real = NULL; + +/** + * Array of all outputs + */ +struct output* outputs = NULL; + +/** + * The nubmer of elements in `outputs` + */ +size_t outputs_n = 0; + +/** + * The server socket's file descriptor + */ +int socketfd = -1; + +/** + * The pathname of the PID file + */ +char* pidpath = NULL; + +/** + * The pathname of the socket + */ +char* socketpath = NULL; + +/** + * Error code returned by libgamma + */ +int gerror; + +/** + * Initialisation stage + * + * Used to keep track on what to destroy, of those things that + * must only be destroyed if they have been initialised + */ +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; + +/** + * The libgamma partition states + */ +libgamma_partition_state_t* partitions = NULL; + +/** + * The libgamma CRTC states + */ +libgamma_crtc_state_t* crtcs = NULL; + +/** + * Has the process receive a signal + * telling it to re-execute? + */ +volatile sig_atomic_t reexec = 0; + +/** + * Has the process receive a signal + * telling it to terminate? + */ +volatile sig_atomic_t terminate = 0; + + + +/** + * Called when the process receives + * a signal telling it to re-execute + * + * @param signo The received signal + */ +static void sig_reexec(int signo) +{ + reexec = 1; + (void) signo; +} + + +/** + * Called when the process receives + * a signal telling it to terminate + * + * @param signo The received signal + */ +static void sig_terminate(int signo) +{ + terminate = 1; + (void) signo; +} + + +/** + * Get the pathname of the runtime file + * + * @param suffix The suffix for the file + * @return The pathname of the file, `NULL` on error + */ +static char* get_pathname(const char* suffix) +{ + const char* rundir = getenv("XDG_RUNTIME_DIR"); + const char* username = ""; + char* name = NULL; + char* p; + char* rc; + struct passwd* pw; + size_t n; + int saved_errno; + + if (site.site) + { + name = memdup(site.site, strlen(site.site) + 1); + if (name == NULL) + goto fail; + } + else if ((name = libgamma_method_default_site(site.method))) + { + name = memdup(name, strlen(name) + 1); + if (name == NULL) + goto fail; + } + + if (name != NULL) + switch (site.method) + { + case LIBGAMMA_METHOD_X_RANDR: + case LIBGAMMA_METHOD_X_VIDMODE: + if ((p = strrchr(name, ':'))) + if ((p = strchr(p, '.'))) + *p = '\0'; + default: + break; + } + + if (!rundir || !*rundir) + rundir = "/tmp"; + + if ((pw = getpwuid(getuid()))) + username = pw->pw_name ? pw->pw_name : ""; + + n = sizeof("/.coopgammad/~/.") + 3 * sizeof(int); + n += strlen(rundir) + strlen(username) + strlen(name) + strlen(suffix); + if (!(rc = malloc(n))) + goto fail; + sprintf(rc, "%s/.coopgammad/~%s/%i%s%s%s", + rundir, username, site.method, name ? "." : "", name ? name : "", suffix); + return rc; + + fail: + saved_errno = errno; + free(name); + errno = saved_errno; + return NULL; +} + + +/** + * Get the pathname of the socket + * + * @return The pathname of the socket, `NULL` on error + */ +static inline char* get_socket_pathname(void) +{ + return get_pathname(".socket"); +} + + +/** + * Get the pathname of the PID file + * + * @return The pathname of the PID file, `NULL` on error + */ +static inline char* get_pidfile_pathname(void) +{ + return get_pathname(".pid"); +} + + +/** + * 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) + * @return The adjustment method, -1 (negative) on error + */ +static int get_method(char* arg) +{ +#if LIBGAMMA_METHOD_MAX > 5 +# warning libgamma has added more adjustment methods +#endif + + char* p; + + if (!strcmp(arg, "dummy")) return LIBGAMMA_METHOD_DUMMY; + if (!strcmp(arg, "randr")) return LIBGAMMA_METHOD_X_RANDR; + if (!strcmp(arg, "vidmode")) return LIBGAMMA_METHOD_X_VIDMODE; + if (!strcmp(arg, "drm")) return LIBGAMMA_METHOD_LINUX_DRM; + if (!strcmp(arg, "gdi")) return LIBGAMMA_METHOD_W32_GDI; + if (!strcmp(arg, "quartz")) return LIBGAMMA_METHOD_QUARTZ_CORE_GRAPHICS; + + if (!*arg || (/* avoid overflow: */ strlen(arg) > 4)) + goto bad; + for (p = arg; *p; p++) + if (('0' > *p) || (*p > '9')) + goto bad; + + return atoi(arg); + + bad: + fprintf(stderr, "%s: unrecognised adjustment method name: %s\n", argv0, arg); + errno = 0; + return -1; +} + + +/** + * Get the name of a CRTC + * + * @param info Information about the CRTC + * @param crtc libgamma's state for the CRTC + * @return The name of the CRTC, `NULL` on error + */ +static char* get_crtc_name(libgamma_crtc_information_t* info, libgamma_crtc_state_t* crtc) +{ + if ((info->edid_error == 0) && (info->edid != NULL)) + return libgamma_behex_edid(info->edid, info->edid_length); + else if ((info->connector_name_error == 0) && (info->connector_name != NULL)) + { + char* name = malloc(3 * sizeof(size_t) + strlen(info->connector_name) + 2); + if (name != NULL) + sprintf(name, "%zu.%s", crtc->partition->partition, info->connector_name); + return name; + } + else + { + char* name = malloc(2 * 3 * sizeof(size_t) + 2); + if (name != NULL) + sprintf(name, "%zu.%zu", crtc->partition->partition, crtc->crtc); + return name; + } +} + + +/** + * Check whether a PID file is outdated + * + * @param pidfile The PID file + * @param token An environment variable (including both key and value) + * that must exist in the process if it is a coopgammad process + * @return -1: An error occurred + * 0: The service is already running + * 1: The PID file is outdated + */ +static int is_pidfile_reusable(const char* pidfile, const char* token) +{ + /* PORTERS: /proc/$PID/environ is Linux specific */ + + char temp[sizeof("/proc//environ") + 3 * sizeof(pid_t)]; + int fd = -1, saved_errno, tries = 0; + char* content = NULL; + char* p; + pid_t pid = 0; + size_t n; +#if defined(HAVE_LINUX_PROCFS) + char* end; +#else + (void) token; +#endif + + /* Get PID */ + retry: + fd = open(pidfile, O_RDONLY); + if (fd < 0) + return -1; + content = nread(fd, &n); + if (content == NULL) + goto fail; + close(fd), fd = -1; + + if (n == 0) + { + if (++tries > 1) + goto bad; + msleep(100); /* 1 tenth of a second */ + goto retry; + } + + if (('0' > content[0]) || (content[0] > '9')) + goto bad; + if ((content[0] == '0') && ('0' <= content[1]) && (content[1] <= '9')) + goto bad; + for (p = content; *p; p++) + if (('0' <= *p) && (*p <= '9')) + pid = pid * 10 + (*p & 15); + else + break; + if (*p++ != '\n') + goto bad; + if (*p) + goto bad; + if ((size_t)(content - p) != n) + goto bad; + sprintf(temp, "%llu", (unsigned long long)pid); + if (strcmp(content, temp)) + goto bad; + + /* Validate PID */ +#if defined(HAVE_LINUX_PROCFS) + sprintf(temp, "/proc/%llu/environ", (unsigned long long)pid); + fd = open(temp, O_RDONLY); + if (fd < 0) + return ((errno == ENOENT) || (errno == EACCES)) ? 1 : -1; + content = nread(fd, &n); + if (content == NULL) + goto fail; + close(fd), fd = -1; + + for (end = (p = content) + n; p != end; p = strchr(p, '\0') + 1) + if (!strcmp(p, token)) + return 0; +#else + if ((kill(pid, 0) == 0) || (errno == EINVAL)) + return 0; +#endif + + return 1; + bad: + fprintf(stderr, "%s: pid file contain invalid content: %s\n", argv0, pidfile); + errno = 0; + return -1; + fail: + saved_errno = errno; + free(content); + if (fd >= 0) + close(fd); + errno = saved_errno; + return -1; +} + + +/** + * Create PID file + * + * @param pidfile The pathname of the PID file + * @return Zero on success, -1 on error, + * -2 if the service is already running + */ +static int create_pidfile(char* pidfile) +{ + int fd, r, saved_errno; + char* p; + char* token; + + /* Create token used to validate the service. */ + token = malloc(sizeof("COOPGAMMAD_PIDFILE_TOKEN=") + strlen(pidfile)); + if (token == NULL) + return -1; + sprintf(token, "COOPGAMMAD_PIDFILE_TOKEN=%s", pidfile); + if (putenv(token)) + return -1; + + /* Create PID file's directory. */ + for (p = pidfile; *p == '/'; p++); + while ((p = strchr(p, '/'))) + { + *p = '\0'; + if (mkdir(pidfile, 0644) < 0) + if (errno != EEXIST) + return -1; + *p++ = '/'; + } + + /* Create PID file. */ + retry: + fd = open(pidfile, O_CREAT | O_EXCL, 0644); + if (fd < 0) + { + if (errno == EINTR) + goto retry; + if (errno != EEXIST) + return -1; + r = is_pidfile_reusable(pidfile, token); + if (r > 0) + { + unlink(pidfile); + goto retry; + } + else if (r < 0) + goto fail; + fprintf(stderr, "%s: service is already running\n", argv0); + errno = 0; + return -2; + } + + /* Write PID to PID file. */ + if (dprintf(fd, "%llu\n", (unsigned long long)getpid()) < 0) + goto fail; + + /* Done */ + if (close(fd) < 0) + if (errno != EINTR) + return -1; + return 0; + fail: + saved_errno = errno; + close(fd); + unlink(pidfile); + errno = saved_errno; + return -1; +} + + +/** + * Initialise the process + * + * @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 + * @return 1: Success + * 2: Normal failure + * 3: Libgamma failure + * 4: The service is already running + * Otherwise: The negative of the exit value the + * process should have and shall exit immediately + */ +static int initialise(int full, int preserve, int foreground, int keep_stderr) +{ + struct sockaddr_un address; + struct rlimit rlimit; + size_t i, j, n, n0; + sigset_t mask; + char* sitename_dup = NULL; + int r; + + /* Zero out some memory so it can be destoried safely. */ + memset(&site, 0, sizeof(site)); + + 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)) + return fprintf(stderr, "%s: no adjustment method available\n", argv0), -1; + + /* Get site */ + if (sitename != NULL) + if (!(sitename_dup = memdup(sitename, strlen(sitename) + 1))) + goto fail; + if ((gerror = libgamma_site_initialise(&site, method, sitename_dup))) + goto fail_libgamma; + + if (full) + { + /* 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 */ + if (site.partitions_available) + if (!(partitions = calloc(site.partitions_available, sizeof(*partitions)))) + goto fail; + for (i = 0; i < site.partitions_available; i++) + { + if ((gerror = libgamma_partition_initialise(partitions + i, &site, i))) + goto fail_libgamma; + outputs_n += partitions[i].crtcs_available; + } + + /* Get CRTC:s */ + if (outputs_n) + if (!(crtcs = calloc(outputs_n, sizeof(*crtcs)))) + goto fail; + for (i = 0, j = n = 0; i < site.partitions_available; i++) + for (n0 = n, n += partitions[i].crtcs_available; j < n; j++) + if ((gerror = libgamma_crtc_initialise(crtcs + j, partitions + i, j - n0))) + goto fail_libgamma; + + /* Get CRTC information */ + if (outputs_n) + if (!(outputs = calloc(outputs_n, sizeof(*outputs)))) + goto fail; + for (i = 0; i < outputs_n; i++) + { + libgamma_crtc_information_t info; + int saved_errno; + libgamma_get_crtc_information(&info, crtcs + i, + LIBGAMMA_CRTC_INFO_EDID | + LIBGAMMA_CRTC_INFO_MACRO_RAMP | + LIBGAMMA_CRTC_INFO_GAMMA_SUPPORT | + LIBGAMMA_CRTC_INFO_CONNECTOR_NAME); + outputs[i].depth = info.gamma_depth_error ? 0 : info.gamma_depth; + outputs[i].red_size = info.gamma_size_error ? 0 : info.red_gamma_size; + outputs[i].green_size = info.gamma_size_error ? 0 : info.green_gamma_size; + outputs[i].blue_size = info.gamma_size_error ? 0 : info.blue_gamma_size; + outputs[i].supported = info.gamma_support_error ? 0 : info.gamma_support; + if (outputs[i].depth == 0 || outputs[i].red_size == 0 || + outputs[i].green_size == 0 || outputs[i].blue_size == 0) + outputs[i].supported = 0; + outputs[i].name = get_crtc_name(&info, crtcs + i); + saved_errno = errno; + outputs[i].crtc = crtcs + i; + libgamma_crtc_information_destroy(&info); + outputs[i].ramps_size = outputs[i].red_size + outputs[i].green_size + outputs[i].blue_size; + /* outputs[i].ramps_size will be multipled by the stop-size later */ + errno = saved_errno; + if (outputs[i].name == NULL) + goto fail; + } + free(crtcs), crtcs = NULL; + + /* Sort outputs */ + qsort(outputs, outputs_n, sizeof(*outputs), output_cmp_by_name); + + /* Load current gamma ramps */ +#define LOAD_RAMPS(SUFFIX, MEMBER) \ + do \ + { \ + libgamma_gamma_ramps##SUFFIX##_initialise(&(outputs[i].saved_ramps.MEMBER)); \ + gerror = libgamma_crtc_get_gamma_ramps##SUFFIX(outputs[i].crtc, &(outputs[i].saved_ramps.MEMBER)); \ + if (gerror) \ + { \ + libgamma_perror(argv0, gerror); \ + outputs[i].supported = LIBGAMMA_NO; \ + libgamma_gamma_ramps##SUFFIX##_destroy(&(outputs[i].saved_ramps.MEMBER)); \ + memset(&(outputs[i].saved_ramps.MEMBER), 0, sizeof(outputs[i].saved_ramps.MEMBER)); \ + } \ + } \ + while (0) + for (i = 0; i < outputs_n; i++) + if (outputs[i].supported != LIBGAMMA_NO) + switch (outputs[i].depth) + { + case 8: + outputs[i].ramps_size *= sizeof(uint8_t); + LOAD_RAMPS(8, u8); + break; + case 16: + outputs[i].ramps_size *= sizeof(uint16_t); + LOAD_RAMPS(16, u16); + break; + case 32: + outputs[i].ramps_size *= sizeof(uint32_t); + LOAD_RAMPS(32, u32); + break; + default: + outputs[i].depth = 64; + /* fall through */ + case 64: + outputs[i].ramps_size *= sizeof(uint64_t); + LOAD_RAMPS(64, u64); + break; + case -1: + outputs[i].ramps_size *= sizeof(float); + LOAD_RAMPS(f, f); + break; + case -2: + outputs[i].ramps_size *= sizeof(double); + LOAD_RAMPS(d, d); + break; + } + + /* Preserve current gamma ramps at priority=0 if -p */ + if (preserve) + for (i = 0; i < outputs_n; i++) + { + struct filter filter = { + .client = -1, + .crtc = NULL, + .priority = 0, + .class = NULL, + .lifespan = LIFESPAN_UNTIL_REMOVAL, + .ramps = NULL + }; + outputs[i].table_filters = calloc(4, sizeof(*(outputs[i].table_filters))); + outputs[i].table_sums = calloc(4, sizeof(*(outputs[i].table_sums))); + outputs[i].table_alloc = 4; + outputs[i].table_size = 1; + filter.class = memdup(PKGNAME "::" COMMAND "::preserved", sizeof(PKGNAME "::" COMMAND "::preserved")); + if (filter.class == NULL) + goto fail; + filter.ramps = memdup(outputs[i].saved_ramps.u8.red, outputs[i].ramps_size); + if (filter.ramps == NULL) + goto fail; + outputs[i].table_filters[0] = filter; + COPY_RAMP_SIZES(&(outputs[i].table_sums[0].u8), outputs + i); + if (!gamma_ramps_unmarshal(outputs[i].table_sums, outputs[i].saved_ramps.u8.red, outputs[i].ramps_size)) + goto fail; + } + + if (full) + { + /* 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); + } + + /* Set up signal handlers */ + if (signal(SIGUSR1, sig_reexec) == SIG_ERR) + goto fail; + if (signal(SIGTERM, sig_terminate) == SIG_ERR) + goto fail; + + if (full) + { + /* Initialise the server */ + if (server_initialise() < 0) + goto fail; + init_stage++; + } + + /* Place in the background unless -f */ + if (full && (foreground == 0)) + { + pid_t pid; + int fd = -1, saved_errno; + int notify_rw[2] = { -1, -1 }; + char a_byte = 0; + ssize_t got; + + if (pipe(notify_rw) < 0) + goto fail; + if (notify_rw[0] <= STDERR_FILENO) + if ((notify_rw[0] = dup2atleast(notify_rw[0], STDERR_FILENO + 1)) < 0) + goto fail_background; + if (notify_rw[1] <= STDERR_FILENO) + if ((notify_rw[1] = dup2atleast(notify_rw[1], STDERR_FILENO + 1)) < 0) + goto fail_background; + + switch ((pid = fork())) + { + case -1: + goto fail_background; + case 0: + /* Child */ + close(notify_rw[0]), notify_rw[0] = -1; + if (setsid() < 0) + goto fail_background; + switch ((pid = fork())) + { + case -1: + goto fail_background; + case 0: + /* Replace std* with /dev/null */ + fd = open("/dev/null", O_RDWR); + if (fd < 0) + goto fail; +#define xdup2(s, d) do if (s != d) { close(d); if (dup2(s, d) < 0) goto fail; } while (0) + xdup2(fd, STDIN_FILENO); + xdup2(fd, STDOUT_FILENO); + if (keep_stderr) + xdup2(fd, STDERR_FILENO); + if (fd > STDERR_FILENO) + close(fd); + fd = -1; + + /* Update PID file */ + fd = open(pidpath, O_WRONLY); + if (fd < 0) + goto fail_background; + if (dprintf(fd, "%llu\n", (unsigned long long)getpid()) < 0) + goto fail_background; + close(fd), fd = -1; + + /* Notify */ + if (write(notify_rw[1], &a_byte, 1) <= 0) + goto fail_background; + close(notify_rw[1]); + break; + default: + /* Parent */ + return 0; + } + break; + default: + /* Parent */ + close(notify_rw[1]), notify_rw[1] = -1; + got = read(notify_rw[0], &a_byte, 1); + if (got < 0) + goto fail_background; + close(notify_rw[0]); + return -(got == 0); + } + + goto done_background; + fail_background: + saved_errno = errno; + if (fd >= 0) close(fd); + if (notify_rw[0] >= 0) close(notify_rw[0]); + if (notify_rw[1] >= 0) close(notify_rw[1]); + errno = saved_errno; + done_background:; + } + else if (full) + { + /* Signal the spawner that the service is ready */ + close(STDOUT_FILENO); + /* Avoid potential catastrophes that would occur if a library that is being + * used was so mindless as to write to stdout. */ + if (dup2(STDERR_FILENO, STDOUT_FILENO) < 0) + perror(argv0); + } + + return 1; + fail: + return 2; + fail_libgamma: + return 3; + already_running: + return 4; +} + + +/** + * Deinitialise the process + * + * @param full Perform a full deinitialisation, shall be + * done iff the process is going to re-execute + */ +static void destroy(int full) +{ + size_t i; + + if (init_stage >= 1) + server_destroy(full); + if (full && (socketfd >= 0)) + { + shutdown(socketfd, SHUT_RDWR); + close(socketfd); + unlink(socketpath); + } +#define RESTORE_RAMPS(SUFFIX, MEMBER) \ + do \ + if (outputs[i].saved_ramps.MEMBER.red != NULL) \ + { \ + gerror = libgamma_crtc_set_gamma_ramps##SUFFIX(outputs[i].crtc, outputs[i].saved_ramps.MEMBER); \ + if (gerror) \ + libgamma_perror(argv0, gerror); \ + } \ + while (0) + if (outputs != NULL) + for (i = 0; i < outputs_n; i++) + { + if (full && (outputs[i].supported != LIBGAMMA_NO)) + switch (outputs[i].depth) + { + case 8: + RESTORE_RAMPS(8, u8); + break; + case 16: + RESTORE_RAMPS(16, u16); + break; + case 32: + RESTORE_RAMPS(32, u32); + break; + case 64: + RESTORE_RAMPS(64, u64); + break; + case -1: + RESTORE_RAMPS(f, f); + break; + case -2: + RESTORE_RAMPS(d, d); + break; + default: + break; /* impossible */ + } + if (crtcs == NULL) + libgamma_crtc_destroy(outputs[i].crtc + i); + output_destroy(outputs + i); + } + free(outputs); + if (crtcs != NULL) + for (i = 0; i < outputs_n; i++) + libgamma_crtc_destroy(crtcs + i); + free(crtcs); + if (partitions != NULL) + for (i = 0; i < site.partitions_available; i++) + libgamma_partition_destroy(partitions + i); + free(partitions); + libgamma_site_destroy(&site); + free(socketpath); + if (full && (pidpath != NULL)) + 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 bytes + */ +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; +} + + +/** + * Unmarshal the state of the process + * + * @param buf Buffer with the marshalled data + * @return The number of marshalled bytes, 0 on error + */ +static size_t unmarshal(void* buf) +{ + size_t off = 0, i, n; + char* bs = buf; + + if (*(int*)(bs + off) != MARSHAL_VERSION) + { + fprintf(stderr, "%s: re-executing to incompatible version, sorry about that\n", argv0); + errno = 0; + return 0; + } + off += sizeof(int); + + if (*(bs + off)) + { + off += 1; + n = strlen(bs + off) + 1; + if (!(argv0_real = memdup(bs + off, n))) + return 0; + off += n; + } + else + off += 1; + + outputs_n = *(size_t*)(bs + off); + off += sizeof(size_t); + + for (i = 0; i < outputs_n; i++) + { + off += n = output_unmarshal(outputs + i, bs + off); + if (n == 0) + return 0; + } + + socketfd = *(int*)(bs + off); + off += sizeof(int); + + n = strlen(bs + off) + 1; + if (!(pidpath = memdup(bs + off, n))) + return 0; + off += n; + + n = strlen(bs + off) + 1; + if (!(socketpath = memdup(bs + off, n))) + return 0; + off += n; + + off += n = server_unmarshal(bs + off); + if (n == 0) + return 0; + + init_stage = *(int*)(bs + off); + off += sizeof(int); + + method = *(int*)(bs + off); + off += sizeof(int); + + if (*(int*)(bs + off)) + { + off += sizeof(int); + n = strlen(bs + off) + 1; + if (!(sitename = memdup(bs + off, n))) + return 0; + off += n; + } + else + off += sizeof(int); + + return off; +} + + +/** + * Unmarshal the state of the process and merge with new state + * + * @param statefile The state file + * @return Zero on success, -1 on error + */ +static int unmarshal_and_merge_state(const char* statefile) +{ + struct output* new_outputs = outputs; + struct output* old_outputs = NULL; + size_t new_outputs_n = outputs_n; + size_t old_outputs_n = 0; + size_t i, j, k; + void* marshalled = NULL; + int fd = -1, saved_errno; + + outputs = NULL; + outputs_n = 0; + + fd = open(statefile, O_RDONLY); + if (fd < 0) + goto fail; + if (!(marshalled = nread(fd, &k))) + goto fail; + close(fd), fd = -1; + unlink(statefile), statefile = NULL; + + if (unmarshal(marshalled) == 0) + goto fail; + free(marshalled), marshalled = NULL; + + old_outputs = outputs, outputs = new_outputs, new_outputs = NULL; + old_outputs_n = outputs_n, outputs_n = new_outputs_n, new_outputs_n = 0; + + i = j = new_outputs_n = 0; + while ((i < old_outputs_n) && (j < outputs_n)) + { + int cmp = strcmp(old_outputs[i].name, outputs[j].name); + if (cmp <= 0) + new_outputs_n++; + i += cmp >= 0; + j += cmp <= 0; + } + new_outputs_n += outputs_n - j; + + new_outputs = calloc(new_outputs_n, sizeof(*new_outputs)); + if (new_outputs == NULL) + goto fail; + + i = j = k = new_outputs_n = 0; + while ((i < old_outputs_n) && (j < outputs_n)) + { + int cmp = strcmp(old_outputs[i].name, outputs[j].name); + int is_same = 0; + if (cmp == 0) + is_same = (old_outputs[i].depth == outputs[j].depth && + old_outputs[i].red_size == outputs[j].red_size && + old_outputs[i].green_size == outputs[j].green_size && + old_outputs[i].blue_size == outputs[j].blue_size); + if (is_same) + { + new_outputs[k] = old_outputs[i]; + new_outputs[k].crtc = outputs[j].crtc; + output_destroy(outputs + j); + k++; + } + else if (cmp <= 0) + new_outputs[k++] = outputs[j]; + i += cmp >= 0; + j += cmp <= 0; + } + while (j < outputs_n) + new_outputs[k++] = outputs[j++]; + + outputs = new_outputs; + outputs_n = new_outputs_n; + + for (i = 0; i < old_outputs_n; i++) + output_destroy(old_outputs + i); + + return 0; + fail: + saved_errno = errno; + if (fd >= 0) + close(fd); + free(marshalled); + for (i = 0; i < old_outputs_n; i++) + output_destroy(old_outputs + i); + free(old_outputs); + errno = saved_errno; + return -1; +} + + +/** + * Print usage information and exit + */ +static void usage(void) +{ + printf("Usage: %s [-m method] [-s site] [-kfp]\n", argv0); + exit(1); +} + + +/** + * Must not be started without stdin, stdout, or stderr (may be /dev/null) + * + * argv[0] must refer to the real command name or pathname, + * otherwise, re-execute will not work + * + * The process closes stdout when the socket has been created + * + * @signal SIGUSR1 Re-execute to updated process image + * @signal SIGTERM Terminate the process gracefully + * + * @param argc The number of elements in `argv` + * @param argv Command line arguments. Recognised options: + * -s SITENAME + * The site to which to connect + * -m METHOD + * Adjustment method name or adjustment method number + * -p + * Preserve current gamma ramps at priority 0 + * -f + * Do not fork the process into the background + * -k + * Keep stderr open + * @return 0: Successful + * 1: An error occurred + * 2: Already running + */ +int main(int argc, char** argv) +{ + int rc = 1, preserve = 0, foreground = 0, keep_stderr = 0, r; + char* statefile = NULL; + char* statebuffer = 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())); + if (method < 0) + goto fail; + break; + case 'p': + preserve = 1; + break; + case 'f': + foreground = 1; + break; + case 'k': + keep_stderr = 1; + break; + case '#': /* Internal, do not document */ + statefile = EARGF(usage()); + break; + default: + usage(); + } + ARGEND; + if (argc > 0) + usage(); + + restart: /* If C had comefrom: comefrom reexec_failure; */ + + switch ((r = initialise(statefile == NULL, preserve, foreground, keep_stderr))) + { + case 1: + break; + case 2: + goto fail; + case 3: + goto fail_libgamma; + case 4: + rc = 2; + goto fail; + default: + return -r; + } + + if (statefile != NULL) + { + if (unmarshal_and_merge_state(statefile) < 0) + goto fail; + unlink(statefile), statefile = NULL; + reexec = 0; /* See `if (reexec && !terminate)` */ + } + + if (reexec && !terminate) + { + size_t buffer_size; + int fd; + + /* `reexec = 0;` is done later in case of re-execute failure, + * since it determines whether `statefile` shall be freed. */ + + statefile = get_state_pathname(); + if (statefile == NULL) + goto fail; + + buffer_size = marshal(NULL); + statebuffer = malloc(buffer_size); + if (statebuffer == NULL) + goto fail; + if (marshal(statebuffer) != buffer_size) + abort(); + + fd = open(statefile, O_CREAT, S_IRUSR | S_IWUSR); + if (fd < 0) + goto fail; + + if (nwrite(fd, statebuffer, buffer_size) != buffer_size) + { + perror(argv0); + close(fd); + errno = 0; + goto fail; + } + free(statebuffer), statebuffer = NULL; + + if ((close(fd) < 0) && (errno != EINTR)) + goto fail; + + destroy(0); + + execlp(argv0_real ? argv0_real : argv0, argv0, "-#", statefile, preserve ? "-p" : NULL, NULL); + perror(argv0); + fprintf(stderr, "%s: restoring state without re-executing\n", argv0); + free(argv0_real), argv0_real = NULL; + goto restart; + } + + rc = 0; + done: + free(statebuffer); + if (statefile) + unlink(statefile); + if (reexec) + free(statefile); + destroy(1); + return rc; + fail: + if (errno != 0) + perror(argv0); + goto done; + fail_libgamma: + libgamma_perror(argv0, gerror); + goto done; +} + |