[thirdparty/systemd.git] / src / systemctl / systemctl-edit.c

/* 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;

                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, NULL);
                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, NULL);
                        if (r < 0)
                                return log_error_errno(r, "Failed to read \"%s\": %m", *path);

                        fprintf(f, "\n\n### %s", *path);
                        if (!isempty(contents)) {
                                _cleanup_free_ char *commented_contents = NULL;

                                commented_contents = strreplace(strstrip(contents), "\n", "\n# ");
                                if (!commented_contents)
                                        return log_oom();
                                fprintf(f, "\n# %s", commented_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, NULL);
        if (r < 0)
                return log_error_errno(r, "Failed to read temporary file \"%s\": %m", path);

        size = strlen(contents);

        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;
}
Commit	Line	Data
db9ecf05	1	/* SPDX-License-Identifier: LGPL-2.1-or-later */
daf71ef6 LP	2
	3	#include "bus-error.h"
	4	#include "copy.h"
85c5d313	5	#include "fd-util.h"
85c5d313	6	#include "fileio.h"
daf71ef6 LP	7	#include "fs-util.h"
	8	#include "mkdir.h"
	9	#include "pager.h"
	10	#include "path-util.h"
	11	#include "pretty-print.h"
	12	#include "process-util.h"
	13	#include "selinux-util.h"
	14	#include "stat-util.h"
	15	#include "systemctl-daemon-reload.h"
	16	#include "systemctl-edit.h"
	17	#include "systemctl-util.h"
	18	#include "systemctl.h"
	19	#include "terminal-util.h"
	20	#include "tmpfile-util.h"
	21
85c5d313	22	#define EDIT_MARKER_START "### Anything between here and the comment below will become the new contents of the file"
	23	#define EDIT_MARKER_END "### Lines below this comment will be discarded"
	24
daf71ef6	25	int cat(int argc, char argv[], void userdata) {
b4c527f4	26	_cleanup_(hashmap_freep) Hashmap cached_name_map = NULL, cached_id_map = NULL;
daf71ef6 LP	27	_cleanup_(lookup_paths_free) LookupPaths lp = {};
	28	_cleanup_strv_free_ char **names = NULL;
	29	char **name;
	30	sd_bus *bus;
	31	bool first = true;
	32	int r, rc = 0;
	33
	34	/* Include all units by default — i.e. continue as if the --all option was used */
	35	if (strv_isempty(arg_states))
	36	arg_all = true;
	37
	38	if (arg_transport != BUS_TRANSPORT_LOCAL)
	39	return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot remotely cat units.");
	40
	41	r = lookup_paths_init(&lp, arg_scope, 0, arg_root);
	42	if (r < 0)
	43	return log_error_errno(r, "Failed to determine unit paths: %m");
	44
	45	r = acquire_bus(BUS_MANAGER, &bus);
	46	if (r < 0)
	47	return r;
	48
	49	r = expand_unit_names(bus, strv_skip(argv, 1), NULL, &names, NULL);
	50	if (r < 0)
	51	return log_error_errno(r, "Failed to expand names: %m");
	52
	53	r = maybe_extend_with_unit_dependencies(bus, &names);
	54	if (r < 0)
	55	return r;
	56
	57	(void) pager_open(arg_pager_flags);
	58
	59	STRV_FOREACH(name, names) {
	60	_cleanup_free_ char *fragment_path = NULL;
	61	_cleanup_strv_free_ char **dropin_paths = NULL;
	62
b4c527f4	63	r = unit_find_paths(bus, *name, &lp, false, &cached_name_map, &cached_id_map, &fragment_path, &dropin_paths);
daf71ef6 LP	64	if (r == -ERFKILL) {
	65	printf("%s# Unit %s is masked%s.\n",
	66	ansi_highlight_magenta(),
	67	*name,
	68	ansi_normal());
	69	continue;
	70	}
	71	if (r == -EKEYREJECTED) {
	72	printf("%s# Unit %s could not be loaded.%s\n",
	73	ansi_highlight_magenta(),
	74	*name,
	75	ansi_normal());
	76	continue;
	77	}
	78	if (r < 0)
	79	return r;
	80	if (r == 0) {
	81	/* Skip units which have no on-disk counterpart, but propagate the error to the
	82	* user */
	83	rc = -ENOENT;
	84	continue;
	85	}
	86
	87	if (first)
	88	first = false;
	89	else
	90	puts("");
	91
	92	if (need_daemon_reload(bus, name) > 0) / ignore errors (<0), this is informational output */
	93	fprintf(stderr,
	94	"%s# Warning: %s changed on disk, the version systemd has loaded is outdated.\n"
	95	"%s# This output shows the current version of the unit's original fragment and drop-in files.\n"
	96	"%s# If fragments or drop-ins were added or removed, they are not properly reflected in this output.\n"
	97	"%s# Run 'systemctl%s daemon-reload' to reload units.%s\n",
	98	ansi_highlight_red(),
	99	*name,
	100	ansi_highlight_red(),
	101	ansi_highlight_red(),
	102	ansi_highlight_red(),
	103	arg_scope == UNIT_FILE_SYSTEM ? "" : " --user",
	104	ansi_normal());
	105
	106	r = cat_files(fragment_path, dropin_paths, 0);
	107	if (r < 0)
	108	return r;
	109	}
	110
	111	return rc;
	112	}
	113
85c5d313	114	static int create_edit_temp_file(const char new_path, const char original_path, char const original_unit_paths, char ret_tmp_fn) {
daf71ef6 LP	115	_cleanup_free_ char *t = NULL;
	116	int r;
	117
	118	assert(new_path);
daf71ef6 LP	119	assert(ret_tmp_fn);
	120
	121	r = tempfn_random(new_path, NULL, &t);
	122	if (r < 0)
	123	return log_error_errno(r, "Failed to determine temporary filename for \"%s\": %m", new_path);
	124
	125	r = mkdir_parents_label(new_path, 0755);
	126	if (r < 0)
	127	return log_error_errno(r, "Failed to create directories for \"%s\": %m", new_path);
	128
85c5d313	129	if (original_path) {
	130	r = mac_selinux_create_file_prepare(new_path, S_IFREG);
	131	if (r < 0)
	132	return r;
daf71ef6	133
85c5d313	134	r = copy_file(original_path, t, 0, 0644, 0, 0, COPY_REFLINK);
	135	if (r == -ENOENT) {
	136	r = touch(t);
	137	mac_selinux_create_file_clear();
	138	if (r < 0)
	139	return log_error_errno(r, "Failed to create temporary file \"%s\": %m", t);
	140	} else {
	141	mac_selinux_create_file_clear();
	142	if (r < 0)
	143	return log_error_errno(r, "Failed to create temporary file for \"%s\": %m", new_path);
	144	}
	145	} else if (original_unit_paths) {
	146	_cleanup_free_ char *new_contents = NULL;
	147	_cleanup_fclose_ FILE *f = NULL;
	148	char **path;
daf71ef6	149
85c5d313	150	r = mac_selinux_create_file_prepare(new_path, S_IFREG);
	151	if (r < 0)
	152	return r;
daf71ef6	153
85c5d313	154	f = fopen(t, "we");
daf71ef6	155	mac_selinux_create_file_clear();
85c5d313	156	if (!f)
85c5d313	157	return log_error_errno(errno, "Failed to open \"%s\": %m", t);
daf71ef6	158
85c5d313	159	r = fchmod(fileno(f), 0644);
daf71ef6	160	if (r < 0)
85c5d313	161	return log_error_errno(errno, "Failed to change mode of \"%s\": %m", t);
85c5d313	162
be81e45c	163	r = read_full_file(new_path, &new_contents, NULL);
85c5d313	164	if (r < 0 && r != -ENOENT)
	165	return log_error_errno(r, "Failed to read \"%s\": %m", new_path);
	166
	167	fprintf(f,
	168	"### Editing %s\n"
	169	EDIT_MARKER_START
	170	"\n\n%s%s\n"
	171	EDIT_MARKER_END,
	172	new_path,
	173	strempty(new_contents),
	174	new_contents && endswith(new_contents, "\n") ? "" : "\n");
	175
	176	/* Add a comment with the contents of the original unit files */
	177	STRV_FOREACH(path, original_unit_paths) {
	178	_cleanup_free_ char *contents = NULL;
	179
	180	/* Skip the file that's being edited */
	181	if (path_equal(*path, new_path))
	182	continue;
	183
be81e45c	184	r = read_full_file(*path, &contents, NULL);
85c5d313	185	if (r < 0)
	186	return log_error_errno(r, "Failed to read \"%s\": %m", *path);
	187
	188	fprintf(f, "\n\n### %s", *path);
	189	if (!isempty(contents)) {
8f3e1b9d DT	190	_cleanup_free_ char *commented_contents = NULL;
	191
	192	commented_contents = strreplace(strstrip(contents), "\n", "\n# ");
	193	if (!commented_contents)
85c5d313	194	return log_oom();
8f3e1b9d	195	fprintf(f, "\n# %s", commented_contents);
85c5d313	196	}
85c5d313	197	}
daf71ef6	198
85c5d313	199	r = fflush_and_check(f);
daf71ef6	200	if (r < 0)
85c5d313	201	return log_error_errno(r, "Failed to create temporary file \"%s\": %m", t);
daf71ef6 LP	202	}
	203
	204	*ret_tmp_fn = TAKE_PTR(t);
	205
	206	return 0;
	207	}
	208
	209	static int get_file_to_edit(
	210	const LookupPaths *paths,
	211	const char *name,
	212	char **ret_path) {
	213
	214	_cleanup_free_ char path = NULL, run = NULL;
	215
	216	assert(name);
	217	assert(ret_path);
	218
	219	path = path_join(paths->persistent_config, name);
	220	if (!path)
	221	return log_oom();
	222
	223	if (arg_runtime) {
	224	run = path_join(paths->runtime_config, name);
	225	if (!run)
	226	return log_oom();
	227	}
	228
	229	if (arg_runtime) {
	230	if (access(path, F_OK) >= 0)
	231	return log_error_errno(SYNTHETIC_ERRNO(EEXIST),
	232	"Refusing to create \"%s\" because it would be overridden by \"%s\" anyway.",
	233	run, path);
	234
	235	*ret_path = TAKE_PTR(run);
	236	} else
	237	*ret_path = TAKE_PTR(path);
	238
	239	return 0;
	240	}
	241
	242	static int unit_file_create_new(
	243	const LookupPaths *paths,
	244	const char *unit_name,
	245	const char *suffix,
85c5d313	246	char ** const original_unit_paths,
daf71ef6 LP	247	char **ret_new_path,
	248	char **ret_tmp_path) {
	249
	250	_cleanup_free_ char new_path = NULL, tmp_path = NULL;
	251	const char *ending;
	252	int r;
	253
	254	assert(unit_name);
	255	assert(ret_new_path);
	256	assert(ret_tmp_path);
	257
	258	ending = strjoina(unit_name, suffix);
	259	r = get_file_to_edit(paths, ending, &new_path);
	260	if (r < 0)
	261	return r;
	262
85c5d313	263	r = create_edit_temp_file(new_path, NULL, original_unit_paths, &tmp_path);
daf71ef6 LP	264	if (r < 0)
	265	return r;
	266
	267	*ret_new_path = TAKE_PTR(new_path);
	268	*ret_tmp_path = TAKE_PTR(tmp_path);
	269
	270	return 0;
	271	}
	272
	273	static int unit_file_create_copy(
	274	const LookupPaths *paths,
	275	const char *unit_name,
	276	const char *fragment_path,
	277	char **ret_new_path,
	278	char **ret_tmp_path) {
	279
	280	_cleanup_free_ char new_path = NULL, tmp_path = NULL;
	281	int r;
	282
	283	assert(fragment_path);
	284	assert(unit_name);
	285	assert(ret_new_path);
	286	assert(ret_tmp_path);
	287
	288	r = get_file_to_edit(paths, unit_name, &new_path);
	289	if (r < 0)
	290	return r;
	291
	292	if (!path_equal(fragment_path, new_path) && access(new_path, F_OK) >= 0) {
	293	char response;
	294
	295	r = ask_char(&response, "yn", "\"%s\" already exists. Overwrite with \"%s\"? [(y)es, (n)o] ", new_path, fragment_path);
	296	if (r < 0)
	297	return r;
	298	if (response != 'y')
	299	return log_warning_errno(SYNTHETIC_ERRNO(EKEYREJECTED), "%s skipped.", unit_name);
	300	}
	301
85c5d313	302	r = create_edit_temp_file(new_path, fragment_path, NULL, &tmp_path);
daf71ef6 LP	303	if (r < 0)
	304	return r;
	305
	306	*ret_new_path = TAKE_PTR(new_path);
	307	*ret_tmp_path = TAKE_PTR(tmp_path);
	308
	309	return 0;
	310	}
	311
	312	static int run_editor(char **paths) {
	313	int r;
	314
	315	assert(paths);
	316
	317	r = safe_fork("(editor)", FORK_RESET_SIGNALS\|FORK_DEATHSIG\|FORK_RLIMIT_NOFILE_SAFE\|FORK_LOG\|FORK_WAIT, NULL);
	318	if (r < 0)
	319	return r;
	320	if (r == 0) {
	321	char editor_args = NULL, tmp_path, **original_path;
	322	size_t n_editor_args = 0, i = 1, argc;
	323	const char *args, editor, *p;
	324
	325	argc = strv_length(paths)/2 + 1;
	326
	327	/* SYSTEMD_EDITOR takes precedence over EDITOR which takes precedence over VISUAL. If
	328	* neither SYSTEMD_EDITOR nor EDITOR nor VISUAL are present, we try to execute well known
	329	* editors. */
	330	editor = getenv("SYSTEMD_EDITOR");
	331	if (!editor)
	332	editor = getenv("EDITOR");
	333	if (!editor)
	334	editor = getenv("VISUAL");
	335
	336	if (!isempty(editor)) {
	337	editor_args = strv_split(editor, WHITESPACE);
	338	if (!editor_args) {
	339	(void) log_oom();
	340	_exit(EXIT_FAILURE);
	341	}
	342	n_editor_args = strv_length(editor_args);
	343	argc += n_editor_args - 1;
	344	}
	345
	346	args = newa(const char*, argc + 1);
	347
	348	if (n_editor_args > 0) {
	349	args[0] = editor_args[0];
	350	for (; i < n_editor_args; i++)
	351	args[i] = editor_args[i];
	352	}
	353
	354	STRV_FOREACH_PAIR(original_path, tmp_path, paths)
	355	args[i++] = *tmp_path;
	356	args[i] = NULL;
	357
	358	if (n_editor_args > 0)
	359	execvp(args[0], (char* const*) args);
	360
	361	FOREACH_STRING(p, "editor", "nano", "vim", "vi") {
	362	args[0] = p;
	363	execvp(p, (char* const*) args);
	364	/* We do not fail if the editor doesn't exist because we want to try each one of them
	365	* before failing. */
	366	if (errno != ENOENT) {
367	log_error_errno(errno, "Failed to execute %s: %m", editor);
368	_exit(EXIT_FAILURE);
369	}
370	}
371
372	log_error("Cannot edit unit(s), no editor available. Please set either $SYSTEMD_EDITOR, $EDITOR or $VISUAL.");
373	_exit(EXIT_FAILURE);
374	}
375
376	return 0;
377	}
378
379	static int find_paths_to_edit(sd_bus bus, char names, char **paths) {
b4c527f4	380	_cleanup_(hashmap_freep) Hashmap cached_name_map = NULL, cached_id_map = NULL;
daf71ef6 LP	381	_cleanup_(lookup_paths_free) LookupPaths lp = {};
	382	char **name;
	383	int r;
	384
	385	assert(names);
	386	assert(paths);
	387
	388	r = lookup_paths_init(&lp, arg_scope, 0, arg_root);
	389	if (r < 0)
	390	return r;
	391
	392	STRV_FOREACH(name, names) {
	393	_cleanup_free_ char path = NULL, new_path = NULL, tmp_path = NULL, tmp_name = NULL;
85c5d313	394	_cleanup_strv_free_ char **unit_paths = NULL;
daf71ef6 LP	395	const char *unit_name;
daf71ef6 LP	396
85c5d313	397	r = unit_find_paths(bus, *name, &lp, false, &cached_name_map, &cached_id_map, &path, &unit_paths);
daf71ef6 LP	398	if (r == -EKEYREJECTED) {
	399	/* If loading of the unit failed server side complete, then the server won't tell us
	400	* the unit file path. In that case, find the file client side. */
	401	log_debug_errno(r, "Unit '%s' was not loaded correctly, retrying client-side.", *name);
e4d22a9f	402	r = unit_find_paths(bus, *name, &lp, true, &cached_name_map, &cached_id_map, &path, &unit_paths);
daf71ef6 LP	403	}
	404	if (r == -ERFKILL)
	405	return log_error_errno(r, "Unit '%s' masked, cannot edit.", *name);
	406	if (r < 0)
	407	return r;
	408
98199724	409	if (!path) {
daf71ef6 LP	410	if (!arg_force) {
	411	log_info("Run 'systemctl edit%s --force --full %s' to create a new unit.",
	412	arg_scope == UNIT_FILE_GLOBAL ? " --global" :
	413	arg_scope == UNIT_FILE_USER ? " --user" : "",
	414	*name);
	415	return -ENOENT;
	416	}
	417
	418	/* Create a new unit from scratch */
	419	unit_name = *name;
	420	r = unit_file_create_new(&lp, unit_name,
	421	arg_full ? NULL : ".d/override.conf",
85c5d313	422	NULL, &new_path, &tmp_path);
daf71ef6	423	} else {
daf71ef6 LP	424	unit_name = basename(path);
	425	/* We follow unit aliases, but we need to propagate the instance */
	426	if (unit_name_is_valid(*name, UNIT_NAME_INSTANCE) &&
	427	unit_name_is_valid(unit_name, UNIT_NAME_TEMPLATE)) {
	428	_cleanup_free_ char *instance = NULL;
	429
	430	r = unit_name_to_instance(*name, &instance);
	431	if (r < 0)
	432	return r;
	433
	434	r = unit_name_replace_instance(unit_name, instance, &tmp_name);
	435	if (r < 0)
	436	return r;
	437
	438	unit_name = tmp_name;
	439	}
	440
	441	if (arg_full)
	442	r = unit_file_create_copy(&lp, unit_name, path, &new_path, &tmp_path);
85c5d313	443	else {
	444	r = strv_prepend(&unit_paths, path);
	445	if (r < 0)
	446	return log_oom();
	447
	448	r = unit_file_create_new(&lp, unit_name, ".d/override.conf", unit_paths, &new_path, &tmp_path);
	449	}
daf71ef6 LP	450	}
	451	if (r < 0)
	452	return r;
	453
	454	r = strv_push_pair(paths, new_path, tmp_path);
	455	if (r < 0)
	456	return log_oom();
	457
	458	new_path = tmp_path = NULL;
	459	}
	460
	461	return 0;
	462	}
	463
85c5d313	464	static int trim_edit_markers(const char *path) {
	465	_cleanup_free_ char *contents = NULL;
	466	char *contents_start = NULL;
	467	const char *contents_end = NULL;
	468	size_t size;
	469	int r;
	470
	471	/* Trim out the lines between the two markers */
be81e45c	472	r = read_full_file(path, &contents, NULL);
85c5d313	473	if (r < 0)
	474	return log_error_errno(r, "Failed to read temporary file \"%s\": %m", path);
	475
be81e45c LP	476	size = strlen(contents);
be81e45c LP	477
85c5d313	478	contents_start = strstr(contents, EDIT_MARKER_START);
	479	if (contents_start)
	480	contents_start += strlen(EDIT_MARKER_START);
	481	else
	482	contents_start = contents;
	483
	484	contents_end = strstr(contents_start, EDIT_MARKER_END);
	485	if (contents_end)
	486	strshorten(contents_start, contents_end - contents_start);
	487
	488	contents_start = strstrip(contents_start);
	489
	490	/* Write new contents if the trimming actually changed anything */
	491	if (strlen(contents) != size) {
	492	r = write_string_file(path, contents_start, WRITE_STRING_FILE_CREATE \| WRITE_STRING_FILE_TRUNCATE \| WRITE_STRING_FILE_AVOID_NEWLINE);
	493	if (r < 0)
	494	return log_error_errno(r, "Failed to modify temporary file \"%s\": %m", path);
	495	}
	496
	497	return 0;
	498	}
	499
daf71ef6 LP	500	int edit(int argc, char argv[], void userdata) {
	501	_cleanup_(lookup_paths_free) LookupPaths lp = {};
	502	_cleanup_strv_free_ char **names = NULL;
	503	_cleanup_strv_free_ char **paths = NULL;
	504	char original, tmp;
	505	sd_bus *bus;
	506	int r;
	507
	508	if (!on_tty())
	509	return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit units if not on a tty.");
	510
	511	if (arg_transport != BUS_TRANSPORT_LOCAL)
	512	return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit units remotely.");
	513
	514	r = lookup_paths_init(&lp, arg_scope, 0, arg_root);
	515	if (r < 0)
	516	return log_error_errno(r, "Failed to determine unit paths: %m");
	517
	518	r = mac_selinux_init();
	519	if (r < 0)
	520	return r;
	521
	522	r = acquire_bus(BUS_MANAGER, &bus);
	523	if (r < 0)
	524	return r;
	525
	526	r = expand_unit_names(bus, strv_skip(argv, 1), NULL, &names, NULL);
	527	if (r < 0)
	528	return log_error_errno(r, "Failed to expand names: %m");
	529
	530	STRV_FOREACH(tmp, names) {
	531	r = unit_is_masked(bus, &lp, *tmp);
	532	if (r < 0)
	533	return r;
	534	if (r > 0)
	535	return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Cannot edit %s: unit is masked.", *tmp);
	536	}
	537
	538	r = find_paths_to_edit(bus, names, &paths);
	539	if (r < 0)
	540	return r;
	541
	542	if (strv_isempty(paths))
	543	return -ENOENT;
	544
	545	r = run_editor(paths);
	546	if (r < 0)
	547	goto end;
	548
	549	STRV_FOREACH_PAIR(original, tmp, paths) {
	550	/* If the temporary file is empty we ignore it. This allows the user to cancel the
	551	* modification. */
85c5d313	552	r = trim_edit_markers(*tmp);
	553	if (r < 0)
	554	continue;
	555
daf71ef6 LP	556	if (null_or_empty_path(*tmp)) {
	557	log_warning("Editing \"%s\" canceled: temporary file is empty.", *original);
	558	continue;
	559	}
	560
	561	r = rename(tmp, original);
	562	if (r < 0) {
	563	r = log_error_errno(errno, "Failed to rename \"%s\" to \"%s\": %m", tmp, original);
	564	goto end;
	565	}
	566	}
	567
	568	r = 0;
	569
	570	if (!arg_no_reload && !install_client_side())
	571	r = daemon_reload(argc, argv, userdata);
	572
	573	end:
	574	STRV_FOREACH_PAIR(original, tmp, paths) {
	575	(void) unlink(*tmp);
	576
	577	/* Removing empty dropin dirs */
	578	if (!arg_full) {
	579	_cleanup_free_ char *dir;
	580
	581	dir = dirname_malloc(*original);
	582	if (!dir)
	583	return log_oom();
	584
	585	/* No need to check if the dir is empty, rmdir does nothing if it is not the case. */
	586	(void) rmdir(dir);
	587	}
	588	}
	589
	590	return r;
	591	}