diff options
Diffstat (limited to '')
-rw-r--r-- | src/systemctl/systemctl-edit.c | 588 |
1 files changed, 588 insertions, 0 deletions
diff --git a/src/systemctl/systemctl-edit.c b/src/systemctl/systemctl-edit.c new file mode 100644 index 0000000..4186ec3 --- /dev/null +++ b/src/systemctl/systemctl-edit.c @@ -0,0 +1,588 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include "bus-error.h" +#include "copy.h" +#include "fd-util.h" +#include "fileio.h" +#include "fs-util.h" +#include "mkdir.h" +#include "pager.h" +#include "path-util.h" +#include "pretty-print.h" +#include "process-util.h" +#include "selinux-util.h" +#include "stat-util.h" +#include "systemctl-daemon-reload.h" +#include "systemctl-edit.h" +#include "systemctl-util.h" +#include "systemctl.h" +#include "terminal-util.h" +#include "tmpfile-util.h" + +#define EDIT_MARKER_START "### Anything between here and the comment below will become the new contents of the file" +#define EDIT_MARKER_END "### Lines below this comment will be discarded" + +int cat(int argc, char *argv[], void *userdata) { + _cleanup_(hashmap_freep) Hashmap *cached_name_map = NULL, *cached_id_map = NULL; + _cleanup_(lookup_paths_free) LookupPaths lp = {}; + _cleanup_strv_free_ char **names = NULL; + char **name; + sd_bus *bus; + bool first = true; + int r, rc = 0; + + /* Include all units by default — i.e. continue as if the --all option was used */ + if (strv_isempty(arg_states)) + arg_all = true; + + if (arg_transport != BUS_TRANSPORT_LOCAL) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot remotely cat units."); + + r = lookup_paths_init(&lp, arg_scope, 0, arg_root); + if (r < 0) + return log_error_errno(r, "Failed to determine unit paths: %m"); + + r = acquire_bus(BUS_MANAGER, &bus); + if (r < 0) + return r; + + r = expand_unit_names(bus, strv_skip(argv, 1), NULL, &names, NULL); + if (r < 0) + return log_error_errno(r, "Failed to expand names: %m"); + + r = maybe_extend_with_unit_dependencies(bus, &names); + if (r < 0) + return r; + + (void) pager_open(arg_pager_flags); + + STRV_FOREACH(name, names) { + _cleanup_free_ char *fragment_path = NULL; + _cleanup_strv_free_ char **dropin_paths = NULL; + + r = unit_find_paths(bus, *name, &lp, false, &cached_name_map, &cached_id_map, &fragment_path, &dropin_paths); + if (r == -ERFKILL) { + printf("%s# Unit %s is masked%s.\n", + ansi_highlight_magenta(), + *name, + ansi_normal()); + continue; + } + if (r == -EKEYREJECTED) { + printf("%s# Unit %s could not be loaded.%s\n", + ansi_highlight_magenta(), + *name, + ansi_normal()); + continue; + } + if (r < 0) + return r; + if (r == 0) { + /* Skip units which have no on-disk counterpart, but propagate the error to the + * user */ + rc = -ENOENT; + continue; + } + + if (first) + first = false; + else + puts(""); + + if (need_daemon_reload(bus, *name) > 0) /* ignore errors (<0), this is informational output */ + fprintf(stderr, + "%s# Warning: %s changed on disk, the version systemd has loaded is outdated.\n" + "%s# This output shows the current version of the unit's original fragment and drop-in files.\n" + "%s# If fragments or drop-ins were added or removed, they are not properly reflected in this output.\n" + "%s# Run 'systemctl%s daemon-reload' to reload units.%s\n", + ansi_highlight_red(), + *name, + ansi_highlight_red(), + ansi_highlight_red(), + ansi_highlight_red(), + arg_scope == UNIT_FILE_SYSTEM ? "" : " --user", + ansi_normal()); + + r = cat_files(fragment_path, dropin_paths, 0); + if (r < 0) + return r; + } + + return rc; +} + +static int create_edit_temp_file(const char *new_path, const char *original_path, char ** const original_unit_paths, char **ret_tmp_fn) { + _cleanup_free_ char *t = NULL; + int r; + + assert(new_path); + assert(ret_tmp_fn); + + r = tempfn_random(new_path, NULL, &t); + if (r < 0) + return log_error_errno(r, "Failed to determine temporary filename for \"%s\": %m", new_path); + + r = mkdir_parents_label(new_path, 0755); + if (r < 0) + return log_error_errno(r, "Failed to create directories for \"%s\": %m", new_path); + + if (original_path) { + r = mac_selinux_create_file_prepare(new_path, S_IFREG); + if (r < 0) + return r; + + r = copy_file(original_path, t, 0, 0644, 0, 0, COPY_REFLINK); + if (r == -ENOENT) { + r = touch(t); + mac_selinux_create_file_clear(); + if (r < 0) + return log_error_errno(r, "Failed to create temporary file \"%s\": %m", t); + } else { + mac_selinux_create_file_clear(); + if (r < 0) + return log_error_errno(r, "Failed to create temporary file for \"%s\": %m", new_path); + } + } else if (original_unit_paths) { + _cleanup_free_ char *new_contents = NULL; + _cleanup_fclose_ FILE *f = NULL; + char **path; + size_t size; + + r = mac_selinux_create_file_prepare(new_path, S_IFREG); + if (r < 0) + return r; + + f = fopen(t, "we"); + mac_selinux_create_file_clear(); + if (!f) + return log_error_errno(errno, "Failed to open \"%s\": %m", t); + + r = fchmod(fileno(f), 0644); + if (r < 0) + return log_error_errno(errno, "Failed to change mode of \"%s\": %m", t); + + r = read_full_file(new_path, &new_contents, &size); + if (r < 0 && r != -ENOENT) + return log_error_errno(r, "Failed to read \"%s\": %m", new_path); + + fprintf(f, + "### Editing %s\n" + EDIT_MARKER_START + "\n\n%s%s\n" + EDIT_MARKER_END, + new_path, + strempty(new_contents), + new_contents && endswith(new_contents, "\n") ? "" : "\n"); + + /* Add a comment with the contents of the original unit files */ + STRV_FOREACH(path, original_unit_paths) { + _cleanup_free_ char *contents = NULL; + + /* Skip the file that's being edited */ + if (path_equal(*path, new_path)) + continue; + + r = read_full_file(*path, &contents, &size); + if (r < 0) + return log_error_errno(r, "Failed to read \"%s\": %m", *path); + + fprintf(f, "\n\n### %s", *path); + if (!isempty(contents)) { + contents = strreplace(strstrip(contents), "\n", "\n# "); + if (!contents) + return log_oom(); + fprintf(f, "\n# %s", contents); + } + } + + r = fflush_and_check(f); + if (r < 0) + return log_error_errno(r, "Failed to create temporary file \"%s\": %m", t); + } + + *ret_tmp_fn = TAKE_PTR(t); + + return 0; +} + +static int get_file_to_edit( + const LookupPaths *paths, + const char *name, + char **ret_path) { + + _cleanup_free_ char *path = NULL, *run = NULL; + + assert(name); + assert(ret_path); + + path = path_join(paths->persistent_config, name); + if (!path) + return log_oom(); + + if (arg_runtime) { + run = path_join(paths->runtime_config, name); + if (!run) + return log_oom(); + } + + if (arg_runtime) { + if (access(path, F_OK) >= 0) + return log_error_errno(SYNTHETIC_ERRNO(EEXIST), + "Refusing to create \"%s\" because it would be overridden by \"%s\" anyway.", + run, path); + + *ret_path = TAKE_PTR(run); + } else + *ret_path = TAKE_PTR(path); + + return 0; +} + +static int unit_file_create_new( + const LookupPaths *paths, + const char *unit_name, + const char *suffix, + char ** const original_unit_paths, + char **ret_new_path, + char **ret_tmp_path) { + + _cleanup_free_ char *new_path = NULL, *tmp_path = NULL; + const char *ending; + int r; + + assert(unit_name); + assert(ret_new_path); + assert(ret_tmp_path); + + ending = strjoina(unit_name, suffix); + r = get_file_to_edit(paths, ending, &new_path); + if (r < 0) + return r; + + r = create_edit_temp_file(new_path, NULL, original_unit_paths, &tmp_path); + if (r < 0) + return r; + + *ret_new_path = TAKE_PTR(new_path); + *ret_tmp_path = TAKE_PTR(tmp_path); + + return 0; +} + +static int unit_file_create_copy( + const LookupPaths *paths, + const char *unit_name, + const char *fragment_path, + char **ret_new_path, + char **ret_tmp_path) { + + _cleanup_free_ char *new_path = NULL, *tmp_path = NULL; + int r; + + assert(fragment_path); + assert(unit_name); + assert(ret_new_path); + assert(ret_tmp_path); + + r = get_file_to_edit(paths, unit_name, &new_path); + if (r < 0) + return r; + + if (!path_equal(fragment_path, new_path) && access(new_path, F_OK) >= 0) { + char response; + + r = ask_char(&response, "yn", "\"%s\" already exists. Overwrite with \"%s\"? [(y)es, (n)o] ", new_path, fragment_path); + if (r < 0) + return r; + if (response != 'y') + return log_warning_errno(SYNTHETIC_ERRNO(EKEYREJECTED), "%s skipped.", unit_name); + } + + r = create_edit_temp_file(new_path, fragment_path, NULL, &tmp_path); + if (r < 0) + return r; + + *ret_new_path = TAKE_PTR(new_path); + *ret_tmp_path = TAKE_PTR(tmp_path); + + return 0; +} + +static int run_editor(char **paths) { + int r; + + assert(paths); + + r = safe_fork("(editor)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG|FORK_WAIT, NULL); + if (r < 0) + return r; + if (r == 0) { + char **editor_args = NULL, **tmp_path, **original_path; + size_t n_editor_args = 0, i = 1, argc; + const char **args, *editor, *p; + + argc = strv_length(paths)/2 + 1; + + /* SYSTEMD_EDITOR takes precedence over EDITOR which takes precedence over VISUAL. If + * neither SYSTEMD_EDITOR nor EDITOR nor VISUAL are present, we try to execute well known + * editors. */ + editor = getenv("SYSTEMD_EDITOR"); + if (!editor) + editor = getenv("EDITOR"); + if (!editor) + editor = getenv("VISUAL"); + + if (!isempty(editor)) { + editor_args = strv_split(editor, WHITESPACE); + if (!editor_args) { + (void) log_oom(); + _exit(EXIT_FAILURE); + } + n_editor_args = strv_length(editor_args); + argc += n_editor_args - 1; + } + + args = newa(const char*, argc + 1); + + if (n_editor_args > 0) { + args[0] = editor_args[0]; + for (; i < n_editor_args; i++) + args[i] = editor_args[i]; + } + + STRV_FOREACH_PAIR(original_path, tmp_path, paths) + args[i++] = *tmp_path; + args[i] = NULL; + + if (n_editor_args > 0) + execvp(args[0], (char* const*) args); + + FOREACH_STRING(p, "editor", "nano", "vim", "vi") { + args[0] = p; + execvp(p, (char* const*) args); + /* We do not fail if the editor doesn't exist because we want to try each one of them + * before failing. */ + if (errno != ENOENT) { + log_error_errno(errno, "Failed to execute %s: %m", editor); + _exit(EXIT_FAILURE); + } + } + + log_error("Cannot edit unit(s), no editor available. Please set either $SYSTEMD_EDITOR, $EDITOR or $VISUAL."); + _exit(EXIT_FAILURE); + } + + return 0; +} + +static int find_paths_to_edit(sd_bus *bus, char **names, char ***paths) { + _cleanup_(hashmap_freep) Hashmap *cached_name_map = NULL, *cached_id_map = NULL; + _cleanup_(lookup_paths_free) LookupPaths lp = {}; + char **name; + int r; + + assert(names); + assert(paths); + + r = lookup_paths_init(&lp, arg_scope, 0, arg_root); + if (r < 0) + return r; + + STRV_FOREACH(name, names) { + _cleanup_free_ char *path = NULL, *new_path = NULL, *tmp_path = NULL, *tmp_name = NULL; + _cleanup_strv_free_ char **unit_paths = NULL; + const char *unit_name; + + r = unit_find_paths(bus, *name, &lp, false, &cached_name_map, &cached_id_map, &path, &unit_paths); + if (r == -EKEYREJECTED) { + /* If loading of the unit failed server side complete, then the server won't tell us + * the unit file path. In that case, find the file client side. */ + log_debug_errno(r, "Unit '%s' was not loaded correctly, retrying client-side.", *name); + r = unit_find_paths(bus, *name, &lp, true, &cached_name_map, &cached_id_map, &path, &unit_paths); + } + if (r == -ERFKILL) + return log_error_errno(r, "Unit '%s' masked, cannot edit.", *name); + if (r < 0) + return r; + + if (!path) { + if (!arg_force) { + log_info("Run 'systemctl edit%s --force --full %s' to create a new unit.", + arg_scope == UNIT_FILE_GLOBAL ? " --global" : + arg_scope == UNIT_FILE_USER ? " --user" : "", + *name); + return -ENOENT; + } + + /* Create a new unit from scratch */ + unit_name = *name; + r = unit_file_create_new(&lp, unit_name, + arg_full ? NULL : ".d/override.conf", + NULL, &new_path, &tmp_path); + } else { + unit_name = basename(path); + /* We follow unit aliases, but we need to propagate the instance */ + if (unit_name_is_valid(*name, UNIT_NAME_INSTANCE) && + unit_name_is_valid(unit_name, UNIT_NAME_TEMPLATE)) { + _cleanup_free_ char *instance = NULL; + + r = unit_name_to_instance(*name, &instance); + if (r < 0) + return r; + + r = unit_name_replace_instance(unit_name, instance, &tmp_name); + if (r < 0) + return r; + + unit_name = tmp_name; + } + + if (arg_full) + r = unit_file_create_copy(&lp, unit_name, path, &new_path, &tmp_path); + else { + r = strv_prepend(&unit_paths, path); + if (r < 0) + return log_oom(); + + r = unit_file_create_new(&lp, unit_name, ".d/override.conf", unit_paths, &new_path, &tmp_path); + } + } + if (r < 0) + return r; + + r = strv_push_pair(paths, new_path, tmp_path); + if (r < 0) + return log_oom(); + + new_path = tmp_path = NULL; + } + + return 0; +} + +static int trim_edit_markers(const char *path) { + _cleanup_free_ char *contents = NULL; + char *contents_start = NULL; + const char *contents_end = NULL; + size_t size; + int r; + + /* Trim out the lines between the two markers */ + r = read_full_file(path, &contents, &size); + if (r < 0) + return log_error_errno(r, "Failed to read temporary file \"%s\": %m", path); + + contents_start = strstr(contents, EDIT_MARKER_START); + if (contents_start) + contents_start += strlen(EDIT_MARKER_START); + else + contents_start = contents; + + contents_end = strstr(contents_start, EDIT_MARKER_END); + if (contents_end) + strshorten(contents_start, contents_end - contents_start); + + contents_start = strstrip(contents_start); + + /* Write new contents if the trimming actually changed anything */ + if (strlen(contents) != size) { + r = write_string_file(path, contents_start, WRITE_STRING_FILE_CREATE | WRITE_STRING_FILE_TRUNCATE | WRITE_STRING_FILE_AVOID_NEWLINE); + if (r < 0) + return log_error_errno(r, "Failed to modify temporary file \"%s\": %m", path); + } + + return 0; +} + +int edit(int argc, char *argv[], void *userdata) { + _cleanup_(lookup_paths_free) LookupPaths lp = {}; + _cleanup_strv_free_ char **names = NULL; + _cleanup_strv_free_ char **paths = NULL; + char **original, **tmp; + sd_bus *bus; + int r; + + if (!on_tty()) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit units if not on a tty."); + + if (arg_transport != BUS_TRANSPORT_LOCAL) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit units remotely."); + + r = lookup_paths_init(&lp, arg_scope, 0, arg_root); + if (r < 0) + return log_error_errno(r, "Failed to determine unit paths: %m"); + + r = mac_selinux_init(); + if (r < 0) + return r; + + r = acquire_bus(BUS_MANAGER, &bus); + if (r < 0) + return r; + + r = expand_unit_names(bus, strv_skip(argv, 1), NULL, &names, NULL); + if (r < 0) + return log_error_errno(r, "Failed to expand names: %m"); + + STRV_FOREACH(tmp, names) { + r = unit_is_masked(bus, &lp, *tmp); + if (r < 0) + return r; + if (r > 0) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit %s: unit is masked.", *tmp); + } + + r = find_paths_to_edit(bus, names, &paths); + if (r < 0) + return r; + + if (strv_isempty(paths)) + return -ENOENT; + + r = run_editor(paths); + if (r < 0) + goto end; + + STRV_FOREACH_PAIR(original, tmp, paths) { + /* If the temporary file is empty we ignore it. This allows the user to cancel the + * modification. */ + r = trim_edit_markers(*tmp); + if (r < 0) + continue; + + if (null_or_empty_path(*tmp)) { + log_warning("Editing \"%s\" canceled: temporary file is empty.", *original); + continue; + } + + r = rename(*tmp, *original); + if (r < 0) { + r = log_error_errno(errno, "Failed to rename \"%s\" to \"%s\": %m", *tmp, *original); + goto end; + } + } + + r = 0; + + if (!arg_no_reload && !install_client_side()) + r = daemon_reload(argc, argv, userdata); + +end: + STRV_FOREACH_PAIR(original, tmp, paths) { + (void) unlink(*tmp); + + /* Removing empty dropin dirs */ + if (!arg_full) { + _cleanup_free_ char *dir; + + dir = dirname_malloc(*original); + if (!dir) + return log_oom(); + + /* No need to check if the dir is empty, rmdir does nothing if it is not the case. */ + (void) rmdir(dir); + } + } + + return r; +} |