diff options
Diffstat (limited to 'compat/systemd.c')
| -rw-r--r-- | compat/systemd.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/compat/systemd.c b/compat/systemd.c new file mode 100644 index 00000000..6f790a32 --- /dev/null +++ b/compat/systemd.c @@ -0,0 +1,215 @@ +/* $OpenBSD$ */ + +/* + * Copyright (c) 2022 Nicholas Marriott <nicholas.marriott@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER + * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING + * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <sys/types.h> +#include <sys/un.h> + +#include <systemd/sd-bus.h> +#include <systemd/sd-daemon.h> +#include <systemd/sd-login.h> +#include <systemd/sd-id128.h> + +#include <string.h> + +#include "tmux.h" + +int +systemd_activated(void) +{ + return (sd_listen_fds(0) >= 1); +} + +int +systemd_create_socket(int flags, char **cause) +{ + int fds; + int fd; + struct sockaddr_un sa; + socklen_t addrlen = sizeof sa; + + fds = sd_listen_fds(0); + if (fds > 1) { /* too many file descriptors */ + errno = E2BIG; + goto fail; + } + + if (fds == 1) { /* socket-activated */ + fd = SD_LISTEN_FDS_START; + if (!sd_is_socket_unix(fd, SOCK_STREAM, 1, NULL, 0)) { + errno = EPFNOSUPPORT; + goto fail; + } + if (getsockname(fd, (struct sockaddr *)&sa, &addrlen) == -1) + goto fail; + socket_path = xstrdup(sa.sun_path); + return (fd); + } + + return (server_create_socket(flags, cause)); + +fail: + if (cause != NULL) + xasprintf(cause, "systemd socket error (%s)", strerror(errno)); + return (-1); +} + +int +systemd_move_pid_to_new_cgroup(pid_t pid, char **cause) +{ + sd_bus_error error = SD_BUS_ERROR_NULL; + sd_bus_message *m = NULL, *reply = NULL; + sd_bus *bus = NULL; + char *name, *desc, *slice; + sd_id128_t uuid; + int r; + pid_t parent_pid; + + /* Connect to the session bus. */ + r = sd_bus_default_user(&bus); + if (r < 0) { + xasprintf(cause, "failed to connect to session bus: %s", + strerror(-r)); + goto finish; + } + + /* Start building the method call. */ + r = sd_bus_message_new_method_call(bus, &m, + "org.freedesktop.systemd1", + "/org/freedesktop/systemd1", + "org.freedesktop.systemd1.Manager", + "StartTransientUnit"); + if (r < 0) { + xasprintf(cause, "failed to create bus message: %s", + strerror(-r)); + goto finish; + } + + /* Generate a unique name for the new scope, to avoid collisions. */ + r = sd_id128_randomize(&uuid); + if (r < 0) { + xasprintf(cause, "failed to generate uuid: %s", strerror(-r)); + goto finish; + } + xasprintf(&name, "tmux-spawn-" SD_ID128_UUID_FORMAT_STR ".scope", + SD_ID128_FORMAT_VAL(uuid)); + r = sd_bus_message_append(m, "s", name); + free(name); + if (r < 0) { + xasprintf(cause, "failed to append to bus message: %s", + strerror(-r)); + goto finish; + } + + /* Mode: fail if there's a queued unit with the same name. */ + r = sd_bus_message_append(m, "s", "fail"); + if (r < 0) { + xasprintf(cause, "failed to append to bus message: %s", + strerror(-r)); + goto finish; + } + + /* Start properties array. */ + r = sd_bus_message_open_container(m, 'a', "(sv)"); + if (r < 0) { + xasprintf(cause, "failed to start properties array: %s", + strerror(-r)); + goto finish; + } + + parent_pid = getpid(); + xasprintf(&desc, "tmux child pane %ld launched by process %ld", + (long)pid, (long)parent_pid); + r = sd_bus_message_append(m, "(sv)", "Description", "s", desc); + free(desc); + if (r < 0) { + xasprintf(cause, "failed to append to properties: %s", + strerror(-r)); + goto finish; + } + + /* + * Inherit the slice from the parent process, or default to + * "app-tmux.slice" if that fails. + */ + r = sd_pid_get_user_slice(parent_pid, &slice); + if (r < 0) { + slice = xstrdup("app-tmux.slice"); + } + r = sd_bus_message_append(m, "(sv)", "Slice", "s", slice); + free(slice); + if (r < 0) { + xasprintf(cause, "failed to append to properties: %s", + strerror(-r)); + goto finish; + } + + /* PIDs to add to the scope: length - 1 array of uint32_t. */ + r = sd_bus_message_append(m, "(sv)", "PIDs", "au", 1, pid); + if (r < 0) { + xasprintf(cause, "failed to append to properties: %s", + strerror(-r)); + goto finish; + } + + /* Clean up the scope even if it fails. */ + r = sd_bus_message_append(m, "(sv)", "CollectMode", "s", + "inactive-or-failed"); + if (r < 0) { + xasprintf(cause, "failed to append to properties: %s", + strerror(-r)); + goto finish; + } + + /* End properties array. */ + r = sd_bus_message_close_container(m); + if (r < 0) { + xasprintf(cause, "failed to end properties array: %s", + strerror(-r)); + goto finish; + } + + /* aux is currently unused and should be passed an empty array. */ + r = sd_bus_message_append(m, "a(sa(sv))", 0); + if (r < 0) { + xasprintf(cause, "failed to append to bus message: %s", + strerror(-r)); + goto finish; + } + + /* Call the method with a timeout of 1 second = 1e6 us. */ + r = sd_bus_call(bus, m, 1000000, &error, &reply); + if (r < 0) { + if (error.message != NULL) { + /* We have a specific error message from sd-bus. */ + xasprintf(cause, "StartTransientUnit call failed: %s", + error.message); + } else { + xasprintf(cause, "StartTransientUnit call failed: %s", + strerror(-r)); + } + goto finish; + } + +finish: + sd_bus_error_free(&error); + sd_bus_message_unref(m); + sd_bus_message_unref(reply); + sd_bus_unref(bus); + + return (r); +} |