diff options
Diffstat (limited to 'systemd.c')
| -rw-r--r-- | systemd.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/systemd.c b/systemd.c new file mode 100644 index 0000000..f556a55 --- /dev/null +++ b/systemd.c @@ -0,0 +1,321 @@ +#include <string.h> +#include <stdlib.h> +#include <systemd/sd-bus.h> + +#include "main.h" +#include "server.h" +#include "systemd.h" + +#define SYSTEMD_DBUS_SERVICE "org.freedesktop.systemd1" +#define SYSTEMD_DBUS_INTERFACE "org.freedesktop.systemd1.Unit" +#define SYSTEMD_DBUS_PATH_PREFIX "/org/freedesktop/systemd1/unit/" + +static inline char +tohex(uint8_t val) +{ + static const char hex[] = "0123456789abcdef"; + + return hex[val & 0x0f]; +} + +/* + * Creates an escaped D-Bus object path for a given systemd service + * + * Escaping rules are documented here: + * https://dbus.freedesktop.org/doc/dbus-specification.html + * + * Essentially, everyting but a-z, A-Z, 0-9 is replaced by _xx where xx is + * the hexadecimal value of the character. + * + * Example: minecraft@world1.service -> minecraft_40world1_2eservice + */ +char * +systemd_service_object_path(struct cfg *cfg, const char *service) +{ + char *r; + char *d; + const char *s; + + if (empty_str(service)) { + fprintf(stderr, "%s: called with NULL arg\n", __func__); + return NULL; + } + + r = malloc(strlen(SYSTEMD_DBUS_PATH_PREFIX) + strlen(service) * 3 + 1); + if (!r) + return NULL; + + memcpy(r, SYSTEMD_DBUS_PATH_PREFIX, strlen(SYSTEMD_DBUS_PATH_PREFIX)); + d = r + strlen(SYSTEMD_DBUS_PATH_PREFIX); + + for (s = service; *s; s++) { + if ((*s >= 'a' && *s <= 'z') || + (*s >= 'A' && *s <= 'Z') || + (*s >= '0' && *s <= '9')) { + *(d++) = *s; + continue; + } + + *(d++) = '_'; + *(d++) = tohex(*s >> 4); + *(d++) = tohex(*s); + } + + *d = '\0'; + return r; +} + +void +systemd_delete(struct cfg *cfg) +{ + if (!cfg->sd_bus) + return; + + sd_bus_unref(cfg->sd_bus); + cfg->sd_bus = NULL; +} + +static sd_bus * +get_bus(struct cfg *cfg) +{ + int r; + + if (cfg->sd_bus_failed) + return NULL; + + if (!cfg->sd_bus) { + r = sd_bus_open_user(&cfg->sd_bus); + if (r < 0) { + fprintf(stderr, "Failed to connect to user system bus: %s\n", strerror(-r)); + cfg->sd_bus_failed = true; + return NULL; + } + } + + return cfg->sd_bus; +} + +/* + * Check if a systemd service is running. + * + * This is equivalent to (assuming service minecraft@world1): + * gdbus call --session + * --dest org.freedesktop.systemd1 + * --object-path /org/freedesktop/systemd1/unit/minecraft_40world1_2eservice + * --method org.freedesktop.DBus.Properties.Get + * "org.freedesktop.systemd1.Unit" + * "ActiveState" + */ +bool +systemd_service_running(struct cfg *cfg, struct server *server) +{ + sd_bus *bus = get_bus(cfg); + sd_bus_error error = SD_BUS_ERROR_NULL; + char *status = NULL; + int r; + bool running = false; + + if (!bus || !server->systemd_service || !server->systemd_obj) + return false; + + r = sd_bus_get_property_string(bus, + SYSTEMD_DBUS_SERVICE, + server->systemd_obj, + SYSTEMD_DBUS_INTERFACE, + "ActiveState", + &error, + &status); + if (r < 0) { + fprintf(stderr, "%s: failed to get status for service %s (%s): %s\n", + __func__, server->systemd_service, server->systemd_obj, error.message); + goto out; + } + + if (!strcmp(status, "active")) { + running = true; + fprintf(stderr, "Systemd service %s (%s) is active\n", + server->systemd_service, server->systemd_obj); + } else + fprintf(stderr, "Systemd service %s (%s) is not active\n", + server->systemd_service, server->systemd_obj); + +out: + free(status); + sd_bus_error_free(&error); + return running; +} + +static bool +systemd_service_action(struct cfg *cfg, struct server *server, const char *action) +{ + sd_bus_error error = SD_BUS_ERROR_NULL; + sd_bus_message *m = NULL; + sd_bus *bus = get_bus(cfg); + const char *path; + bool performed = false; + int r; + + if (!bus || !server->systemd_service || !server->systemd_obj || !action) + return false; + + r = sd_bus_call_method(bus, + SYSTEMD_DBUS_SERVICE, + server->systemd_obj, + SYSTEMD_DBUS_INTERFACE, + action, + &error, + &m, + "s", + "fail"); + if (r < 0) { + fprintf(stderr, "Failed to perform action %s on systemd service %s: %s\n", + action, server->systemd_service, error.message); + goto out; + } + + r = sd_bus_message_read(m, "o", &path); + if (r < 0) { + fprintf(stderr, "Failed to parse response message: %s\n", strerror(-r)); + goto out; + } + + fprintf(stderr, "Queued %s on service %s as %s\n", + action, server->systemd_service, path); + performed = true; + +out: + sd_bus_error_free(&error); + sd_bus_message_unref(m); + return performed; +} + +/* + * Stop systemd service. + * + * This is equivalent to (assuming service minecraft@world1): + * gdbus call --session + * --dest org.freedesktop.systemd1 + * --object-path /org/freedesktop/systemd1/unit/minecraft_40world1_2eservice + * --method org.freedesktop.systemd1.Unit.Stop "fail" + */ +bool +systemd_service_stop(struct cfg *cfg, struct server *server) +{ + return systemd_service_action(cfg, server, "Stop"); +} + +/* + * Start systemd service. + * + * This is equivalent to (assuming service minecraft@world1): + * gdbus call --session + * --dest org.freedesktop.systemd1 + * --object-path /org/freedesktop/systemd1/unit/minecraft_40world1_2eservice + * --method org.freedesktop.systemd1.Unit.Start "fail" + */ +bool +systemd_service_start(struct cfg *cfg, struct server *server) +{ + return systemd_service_action(cfg, server, "Start"); +} + + +#if 0 + + + + +int main(int argc, char *argv[]) { + sd_bus_error error = SD_BUS_ERROR_NULL; + sd_bus_message *m = NULL; + sd_bus *bus = NULL; + const char *path; + int r; + + /* Connect to the system bus */ + r = sd_bus_open_user(&bus); + if (r < 0) { + fprintf(stderr, "Failed to connect to system bus: %s\n", strerror(-r)); + goto finish; + } + + /* Issue the method call and store the respons message in m */ + r = sd_bus_call_method(bus, + "org.freedesktop.systemd1", /* service to contact */ + "/org/freedesktop/systemd1", /* object path */ + "org.freedesktop.systemd1.Manager", /* interface name */ + "StartUnit", /* method name */ + &error, /* object to return error in */ + &m, /* return message on success */ + "ss", /* input signature */ + "apa.service", /* first argument */ + "fail"); /* second argument */ + if (r < 0) { + fprintf(stderr, "Failed to issue method call: %s\n", error.message); + goto finish; + } + + /* Parse the response message */ + r = sd_bus_message_read(m, "o", &path); + if (r < 0) { + fprintf(stderr, "Failed to parse response message: %s\n", strerror(-r)); + goto finish; + } + printf("Queued service job as %s.\n", path); + + sd_bus_error_free(&error); + sd_bus_message_unref(m); + error = SD_BUS_ERROR_NULL; + m = NULL; + + /* + gdbus call --session + --dest org.freedesktop.systemd1 + --object-path /org/freedesktop/systemd1/unit/myapa_40local2_2eservice + --method org.freedesktop.systemd1.Unit.Start "fail" + + gdbus introspect --session + --dest org.freedesktop.systemd1 + --object-path /org/freedesktop/systemd1/unit/myapa_40local_2eservice + + gdbus call --session + --dest org.freedesktop.systemd1 + --object-path /org/freedesktop/systemd1/unit/myapa_40basker_2eservice + --method org.freedesktop.DBus.Properties.Get + "org.freedesktop.systemd1.Unit" + "ActiveState" + */ + char *res; + r = sd_bus_get_property_string(bus, + "org.freedesktop.systemd1", + "/org/freedesktop/systemd1/unit/apa_2eservice", + "org.freedesktop.systemd1.Unit", + "ActiveState", + &error, + &res); + if (r < 0) { + fprintf(stderr, "Failed to issue prop call: %s\n", error.message); + goto finish; + } + + fprintf(stderr, "RESULT: %s\n", res); +/* + int sd_bus_get_property_string(sd_bus *bus, + const char *destination, + const char *path, + const char *interface, + const char *member, + sd_bus_error *ret_error, + char **ret); + */ +/* +finish: + sd_bus_error_free(&error); + sd_bus_message_unref(m); + sd_bus_unref(bus); + */ + +finish: + return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; +} +#endif |