diff options
Diffstat (limited to '')
-rw-r--r-- | src/shared/install.c | 3479 |
1 files changed, 3479 insertions, 0 deletions
diff --git a/src/shared/install.c b/src/shared/install.c new file mode 100644 index 0000000..302497a --- /dev/null +++ b/src/shared/install.c @@ -0,0 +1,3479 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <errno.h> +#include <fcntl.h> +#include <fnmatch.h> +#include <limits.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +#include "alloc-util.h" +#include "conf-files.h" +#include "conf-parser.h" +#include "def.h" +#include "dirent-util.h" +#include "extract-word.h" +#include "fd-util.h" +#include "fileio.h" +#include "fs-util.h" +#include "hashmap.h" +#include "install-printf.h" +#include "install.h" +#include "locale-util.h" +#include "log.h" +#include "macro.h" +#include "mkdir.h" +#include "path-lookup.h" +#include "path-util.h" +#include "rm-rf.h" +#include "set.h" +#include "special.h" +#include "stat-util.h" +#include "string-table.h" +#include "string-util.h" +#include "strv.h" +#include "unit-file.h" + +#define UNIT_FILE_FOLLOW_SYMLINK_MAX 64 + +typedef enum SearchFlags { + SEARCH_LOAD = 1 << 0, + SEARCH_FOLLOW_CONFIG_SYMLINKS = 1 << 1, + SEARCH_DROPIN = 1 << 2, +} SearchFlags; + +typedef struct { + OrderedHashmap *will_process; + OrderedHashmap *have_processed; +} InstallContext; + +typedef enum { + PRESET_UNKNOWN, + PRESET_ENABLE, + PRESET_DISABLE, +} PresetAction; + +struct UnitFilePresetRule { + char *pattern; + PresetAction action; + char **instances; +}; + +static bool unit_file_install_info_has_rules(const UnitFileInstallInfo *i) { + assert(i); + + return !strv_isempty(i->aliases) || + !strv_isempty(i->wanted_by) || + !strv_isempty(i->required_by); +} + +static bool unit_file_install_info_has_also(const UnitFileInstallInfo *i) { + assert(i); + + return !strv_isempty(i->also); +} + +void unit_file_presets_freep(UnitFilePresets *p) { + if (!p) + return; + + for (size_t i = 0; i < p->n_rules; i++) { + free(p->rules[i].pattern); + strv_free(p->rules[i].instances); + } + + free(p->rules); + p->n_rules = 0; +} + +static const char *const unit_file_type_table[_UNIT_FILE_TYPE_MAX] = { + [UNIT_FILE_TYPE_REGULAR] = "regular", + [UNIT_FILE_TYPE_SYMLINK] = "symlink", + [UNIT_FILE_TYPE_MASKED] = "masked", +}; + +DEFINE_PRIVATE_STRING_TABLE_LOOKUP_TO_STRING(unit_file_type, UnitFileType); + +static int in_search_path(const LookupPaths *p, const char *path) { + _cleanup_free_ char *parent = NULL; + + assert(path); + + parent = dirname_malloc(path); + if (!parent) + return -ENOMEM; + + return path_strv_contains(p->search_path, parent); +} + +static const char* skip_root(const LookupPaths *p, const char *path) { + char *e; + + assert(p); + assert(path); + + if (!p->root_dir) + return path; + + e = path_startswith(path, p->root_dir); + if (!e) + return NULL; + + /* Make sure the returned path starts with a slash */ + if (e[0] != '/') { + if (e == path || e[-1] != '/') + return NULL; + + e--; + } + + return e; +} + +static int path_is_generator(const LookupPaths *p, const char *path) { + _cleanup_free_ char *parent = NULL; + + assert(p); + assert(path); + + parent = dirname_malloc(path); + if (!parent) + return -ENOMEM; + + return path_equal_ptr(parent, p->generator) || + path_equal_ptr(parent, p->generator_early) || + path_equal_ptr(parent, p->generator_late); +} + +static int path_is_transient(const LookupPaths *p, const char *path) { + _cleanup_free_ char *parent = NULL; + + assert(p); + assert(path); + + parent = dirname_malloc(path); + if (!parent) + return -ENOMEM; + + return path_equal_ptr(parent, p->transient); +} + +static int path_is_control(const LookupPaths *p, const char *path) { + _cleanup_free_ char *parent = NULL; + + assert(p); + assert(path); + + parent = dirname_malloc(path); + if (!parent) + return -ENOMEM; + + return path_equal_ptr(parent, p->persistent_control) || + path_equal_ptr(parent, p->runtime_control); +} + +static int path_is_config(const LookupPaths *p, const char *path, bool check_parent) { + _cleanup_free_ char *parent = NULL; + + assert(p); + assert(path); + + /* Note that we do *not* have generic checks for /etc or /run in place, since with + * them we couldn't discern configuration from transient or generated units */ + + if (check_parent) { + parent = dirname_malloc(path); + if (!parent) + return -ENOMEM; + + path = parent; + } + + return path_equal_ptr(path, p->persistent_config) || + path_equal_ptr(path, p->runtime_config); +} + +static int path_is_runtime(const LookupPaths *p, const char *path, bool check_parent) { + _cleanup_free_ char *parent = NULL; + const char *rpath; + + assert(p); + assert(path); + + /* Everything in /run is considered runtime. On top of that we also add + * explicit checks for the various runtime directories, as safety net. */ + + rpath = skip_root(p, path); + if (rpath && path_startswith(rpath, "/run")) + return true; + + if (check_parent) { + parent = dirname_malloc(path); + if (!parent) + return -ENOMEM; + + path = parent; + } + + return path_equal_ptr(path, p->runtime_config) || + path_equal_ptr(path, p->generator) || + path_equal_ptr(path, p->generator_early) || + path_equal_ptr(path, p->generator_late) || + path_equal_ptr(path, p->transient) || + path_equal_ptr(path, p->runtime_control); +} + +static int path_is_vendor_or_generator(const LookupPaths *p, const char *path) { + const char *rpath; + + assert(p); + assert(path); + + rpath = skip_root(p, path); + if (!rpath) + return 0; + + if (path_startswith(rpath, "/usr")) + return true; + +#if HAVE_SPLIT_USR + if (path_startswith(rpath, "/lib")) + return true; +#endif + + if (path_is_generator(p, rpath)) + return true; + + return path_equal(rpath, SYSTEM_DATA_UNIT_PATH); +} + +static const char* config_path_from_flags(const LookupPaths *paths, UnitFileFlags flags) { + assert(paths); + + if (FLAGS_SET(flags, UNIT_FILE_PORTABLE)) + return FLAGS_SET(flags, UNIT_FILE_RUNTIME) ? paths->runtime_attached : paths->persistent_attached; + else + return FLAGS_SET(flags, UNIT_FILE_RUNTIME) ? paths->runtime_config : paths->persistent_config; +} + +int unit_file_changes_add( + UnitFileChange **changes, + size_t *n_changes, + int type, + const char *path, + const char *source) { + + _cleanup_free_ char *p = NULL, *s = NULL; + UnitFileChange *c; + + assert(path); + assert(!changes == !n_changes); + + if (!changes) + return 0; + + c = reallocarray(*changes, *n_changes + 1, sizeof(UnitFileChange)); + if (!c) + return -ENOMEM; + *changes = c; + + p = strdup(path); + if (source) + s = strdup(source); + + if (!p || (source && !s)) + return -ENOMEM; + + path_simplify(p, false); + if (s) + path_simplify(s, false); + + c[*n_changes] = (UnitFileChange) { type, p, s }; + p = s = NULL; + (*n_changes) ++; + return 0; +} + +void unit_file_changes_free(UnitFileChange *changes, size_t n_changes) { + assert(changes || n_changes == 0); + + for (size_t i = 0; i < n_changes; i++) { + free(changes[i].path); + free(changes[i].source); + } + + free(changes); +} + +void unit_file_dump_changes(int r, const char *verb, const UnitFileChange *changes, size_t n_changes, bool quiet) { + bool logged = false; + + assert(changes || n_changes == 0); + /* If verb is not specified, errors are not allowed! */ + assert(verb || r >= 0); + + for (size_t i = 0; i < n_changes; i++) { + assert(verb || changes[i].type >= 0); + + switch(changes[i].type) { + case UNIT_FILE_SYMLINK: + if (!quiet) + log_info("Created symlink %s %s %s.", + changes[i].path, + special_glyph(SPECIAL_GLYPH_ARROW), + changes[i].source); + break; + case UNIT_FILE_UNLINK: + if (!quiet) + log_info("Removed %s.", changes[i].path); + break; + case UNIT_FILE_IS_MASKED: + if (!quiet) + log_info("Unit %s is masked, ignoring.", changes[i].path); + break; + case UNIT_FILE_IS_DANGLING: + if (!quiet) + log_info("Unit %s is an alias to a unit that is not present, ignoring.", + changes[i].path); + break; + case -EEXIST: + if (changes[i].source) + log_error_errno(changes[i].type, + "Failed to %s unit, file %s already exists and is a symlink to %s.", + verb, changes[i].path, changes[i].source); + else + log_error_errno(changes[i].type, + "Failed to %s unit, file %s already exists.", + verb, changes[i].path); + logged = true; + break; + case -ERFKILL: + log_error_errno(changes[i].type, "Failed to %s unit, unit %s is masked.", + verb, changes[i].path); + logged = true; + break; + case -EADDRNOTAVAIL: + log_error_errno(changes[i].type, "Failed to %s unit, unit %s is transient or generated.", + verb, changes[i].path); + logged = true; + break; + case -EUCLEAN: + log_error_errno(changes[i].type, + "Failed to %s unit, \"%s\" is not a valid unit name.", + verb, changes[i].path); + logged = true; + break; + case -ELOOP: + log_error_errno(changes[i].type, "Failed to %s unit, refusing to operate on linked unit file %s", + verb, changes[i].path); + logged = true; + break; + + case -ENOENT: + log_error_errno(changes[i].type, "Failed to %s unit, unit %s does not exist.", verb, changes[i].path); + logged = true; + break; + + default: + assert(changes[i].type < 0); + log_error_errno(changes[i].type, "Failed to %s unit, file %s: %m.", + verb, changes[i].path); + logged = true; + } + } + + if (r < 0 && !logged) + log_error_errno(r, "Failed to %s: %m.", verb); +} + +/** + * Checks if two paths or symlinks from wd are the same, when root is the root of the filesystem. + * wc should be the full path in the host file system. + */ +static bool chroot_symlinks_same(const char *root, const char *wd, const char *a, const char *b) { + assert(path_is_absolute(wd)); + + /* This will give incorrect results if the paths are relative and go outside + * of the chroot. False negatives are possible. */ + + if (!root) + root = "/"; + + a = strjoina(path_is_absolute(a) ? root : wd, "/", a); + b = strjoina(path_is_absolute(b) ? root : wd, "/", b); + return path_equal_or_files_same(a, b, 0); +} + +static int create_symlink( + const LookupPaths *paths, + const char *old_path, + const char *new_path, + bool force, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_free_ char *dest = NULL, *dirname = NULL; + const char *rp; + int r; + + assert(old_path); + assert(new_path); + + rp = skip_root(paths, old_path); + if (rp) + old_path = rp; + + /* Actually create a symlink, and remember that we did. Is + * smart enough to check if there's already a valid symlink in + * place. + * + * Returns 1 if a symlink was created or already exists and points to + * the right place, or negative on error. + */ + + mkdir_parents_label(new_path, 0755); + + if (symlink(old_path, new_path) >= 0) { + unit_file_changes_add(changes, n_changes, UNIT_FILE_SYMLINK, new_path, old_path); + return 1; + } + + if (errno != EEXIST) { + unit_file_changes_add(changes, n_changes, -errno, new_path, NULL); + return -errno; + } + + r = readlink_malloc(new_path, &dest); + if (r < 0) { + /* translate EINVAL (non-symlink exists) to EEXIST */ + if (r == -EINVAL) + r = -EEXIST; + + unit_file_changes_add(changes, n_changes, r, new_path, NULL); + return r; + } + + dirname = dirname_malloc(new_path); + if (!dirname) + return -ENOMEM; + + if (chroot_symlinks_same(paths->root_dir, dirname, dest, old_path)) { + log_debug("Symlink %s → %s already exists", new_path, dest); + return 1; + } + + if (!force) { + unit_file_changes_add(changes, n_changes, -EEXIST, new_path, dest); + return -EEXIST; + } + + r = symlink_atomic(old_path, new_path); + if (r < 0) { + unit_file_changes_add(changes, n_changes, r, new_path, NULL); + return r; + } + + unit_file_changes_add(changes, n_changes, UNIT_FILE_UNLINK, new_path, NULL); + unit_file_changes_add(changes, n_changes, UNIT_FILE_SYMLINK, new_path, old_path); + + return 1; +} + +static int mark_symlink_for_removal( + Set **remove_symlinks_to, + const char *p) { + + char *n; + int r; + + assert(p); + + r = set_ensure_allocated(remove_symlinks_to, &path_hash_ops); + if (r < 0) + return r; + + n = strdup(p); + if (!n) + return -ENOMEM; + + path_simplify(n, false); + + r = set_consume(*remove_symlinks_to, n); + if (r == -EEXIST) + return 0; + if (r < 0) + return r; + + return 1; +} + +static int remove_marked_symlinks_fd( + Set *remove_symlinks_to, + int fd, + const char *path, + const char *config_path, + const LookupPaths *lp, + bool dry_run, + bool *restart, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_closedir_ DIR *d = NULL; + struct dirent *de; + int r = 0; + + assert(remove_symlinks_to); + assert(fd >= 0); + assert(path); + assert(config_path); + assert(lp); + assert(restart); + + d = fdopendir(fd); + if (!d) { + safe_close(fd); + return -errno; + } + + rewinddir(d); + + FOREACH_DIRENT(de, d, return -errno) { + + dirent_ensure_type(d, de); + + if (de->d_type == DT_DIR) { + _cleanup_free_ char *p = NULL; + int nfd, q; + + nfd = openat(fd, de->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW); + if (nfd < 0) { + if (errno == ENOENT) + continue; + + if (r == 0) + r = -errno; + continue; + } + + p = path_make_absolute(de->d_name, path); + if (!p) { + safe_close(nfd); + return -ENOMEM; + } + + /* This will close nfd, regardless whether it succeeds or not */ + q = remove_marked_symlinks_fd(remove_symlinks_to, nfd, p, config_path, lp, dry_run, restart, changes, n_changes); + if (q < 0 && r == 0) + r = q; + + } else if (de->d_type == DT_LNK) { + _cleanup_free_ char *p = NULL, *dest = NULL; + const char *rp; + bool found; + int q; + + if (!unit_name_is_valid(de->d_name, UNIT_NAME_ANY)) + continue; + + p = path_make_absolute(de->d_name, path); + if (!p) + return -ENOMEM; + path_simplify(p, false); + + q = chase_symlinks(p, NULL, CHASE_NONEXISTENT, &dest, NULL); + if (q == -ENOENT) + continue; + if (q < 0) { + if (r == 0) + r = q; + continue; + } + + /* We remove all links pointing to a file or path that is marked, as well as all files sharing + * the same name as a file that is marked. */ + + found = set_contains(remove_symlinks_to, dest) || + set_contains(remove_symlinks_to, basename(dest)) || + set_contains(remove_symlinks_to, de->d_name); + + if (!found) + continue; + + if (!dry_run) { + if (unlinkat(fd, de->d_name, 0) < 0 && errno != ENOENT) { + if (r == 0) + r = -errno; + unit_file_changes_add(changes, n_changes, -errno, p, NULL); + continue; + } + + (void) rmdir_parents(p, config_path); + } + + unit_file_changes_add(changes, n_changes, UNIT_FILE_UNLINK, p, NULL); + + /* Now, remember the full path (but with the root prefix removed) of + * the symlink we just removed, and remove any symlinks to it, too. */ + + rp = skip_root(lp, p); + q = mark_symlink_for_removal(&remove_symlinks_to, rp ?: p); + if (q < 0) + return q; + if (q > 0 && !dry_run) + *restart = true; + } + } + + return r; +} + +static int remove_marked_symlinks( + Set *remove_symlinks_to, + const char *config_path, + const LookupPaths *lp, + bool dry_run, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_close_ int fd = -1; + bool restart; + int r = 0; + + assert(config_path); + assert(lp); + + if (set_size(remove_symlinks_to) <= 0) + return 0; + + fd = open(config_path, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC); + if (fd < 0) + return errno == ENOENT ? 0 : -errno; + + do { + int q, cfd; + restart = false; + + cfd = fcntl(fd, F_DUPFD_CLOEXEC, 3); + if (cfd < 0) + return -errno; + + /* This takes possession of cfd and closes it */ + q = remove_marked_symlinks_fd(remove_symlinks_to, cfd, config_path, config_path, lp, dry_run, &restart, changes, n_changes); + if (r == 0) + r = q; + } while (restart); + + return r; +} + +static int is_symlink_with_known_name(const UnitFileInstallInfo *i, const char *name) { + int r; + + if (streq(name, i->name)) + return true; + + if (strv_contains(i->aliases, name)) + return true; + + /* Look for template symlink matching DefaultInstance */ + if (i->default_instance && unit_name_is_valid(i->name, UNIT_NAME_TEMPLATE)) { + _cleanup_free_ char *s = NULL; + + r = unit_name_replace_instance(i->name, i->default_instance, &s); + if (r < 0) { + if (r != -EINVAL) + return r; + + } else if (streq(name, s)) + return true; + } + + return false; +} + +static int find_symlinks_fd( + const char *root_dir, + const UnitFileInstallInfo *i, + bool match_aliases, + bool ignore_same_name, + int fd, + const char *path, + const char *config_path, + bool *same_name_link) { + + _cleanup_closedir_ DIR *d = NULL; + struct dirent *de; + int r = 0; + + assert(i); + assert(fd >= 0); + assert(path); + assert(config_path); + assert(same_name_link); + + d = fdopendir(fd); + if (!d) { + safe_close(fd); + return -errno; + } + + FOREACH_DIRENT(de, d, return -errno) { + + dirent_ensure_type(d, de); + + if (de->d_type == DT_DIR) { + _cleanup_free_ char *p = NULL; + int nfd, q; + + nfd = openat(fd, de->d_name, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW); + if (nfd < 0) { + if (errno == ENOENT) + continue; + + if (r == 0) + r = -errno; + continue; + } + + p = path_make_absolute(de->d_name, path); + if (!p) { + safe_close(nfd); + return -ENOMEM; + } + + /* This will close nfd, regardless whether it succeeds or not */ + q = find_symlinks_fd(root_dir, i, match_aliases, ignore_same_name, nfd, + p, config_path, same_name_link); + if (q > 0) + return 1; + if (r == 0) + r = q; + + } else if (de->d_type == DT_LNK) { + _cleanup_free_ char *p = NULL, *dest = NULL; + bool found_path = false, found_dest, b = false; + int q; + + /* Acquire symlink name */ + p = path_make_absolute(de->d_name, path); + if (!p) + return -ENOMEM; + + /* Acquire symlink destination */ + q = readlink_malloc(p, &dest); + if (q == -ENOENT) + continue; + if (q < 0) { + if (r == 0) + r = q; + continue; + } + + /* Make absolute */ + if (!path_is_absolute(dest)) { + char *x; + + x = path_join(root_dir, dest); + if (!x) + return -ENOMEM; + + free_and_replace(dest, x); + } + + assert(unit_name_is_valid(i->name, UNIT_NAME_ANY)); + if (!ignore_same_name) + /* Check if the symlink itself matches what we are looking for. + * + * If ignore_same_name is specified, we are in one of the directories which + * have lower priority than the unit file, and even if a file or symlink with + * this name was found, we should ignore it. */ + found_path = streq(de->d_name, i->name); + + /* Check if what the symlink points to matches what we are looking for */ + found_dest = streq(basename(dest), i->name); + + if (found_path && found_dest) { + _cleanup_free_ char *t = NULL; + + /* Filter out same name links in the main + * config path */ + t = path_make_absolute(i->name, config_path); + if (!t) + return -ENOMEM; + + b = path_equal(t, p); + } + + if (b) + *same_name_link = true; + else if (found_path || found_dest) { + if (!match_aliases) + return 1; + + /* Check if symlink name is in the set of names used by [Install] */ + q = is_symlink_with_known_name(i, de->d_name); + if (q < 0) + return q; + if (q > 0) + return 1; + } + } + } + + return r; +} + +static int find_symlinks( + const char *root_dir, + const UnitFileInstallInfo *i, + bool match_name, + bool ignore_same_name, + const char *config_path, + bool *same_name_link) { + + int fd; + + assert(i); + assert(config_path); + assert(same_name_link); + + fd = open(config_path, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC); + if (fd < 0) { + if (IN_SET(errno, ENOENT, ENOTDIR, EACCES)) + return 0; + return -errno; + } + + /* This takes possession of fd and closes it */ + return find_symlinks_fd(root_dir, i, match_name, ignore_same_name, fd, + config_path, config_path, same_name_link); +} + +static int find_symlinks_in_scope( + UnitFileScope scope, + const LookupPaths *paths, + const UnitFileInstallInfo *i, + bool match_name, + UnitFileState *state) { + + bool same_name_link_runtime = false, same_name_link_config = false; + bool enabled_in_runtime = false, enabled_at_all = false; + bool ignore_same_name = false; + char **p; + int r; + + assert(paths); + assert(i); + + /* As we iterate over the list of search paths in paths->search_path, we may encounter "same name" + * symlinks. The ones which are "below" (i.e. have lower priority) than the unit file itself are + * effectively masked, so we should ignore them. */ + + STRV_FOREACH(p, paths->search_path) { + bool same_name_link = false; + + r = find_symlinks(paths->root_dir, i, match_name, ignore_same_name, *p, &same_name_link); + if (r < 0) + return r; + if (r > 0) { + /* We found symlinks in this dir? Yay! Let's see where precisely it is enabled. */ + + if (path_equal_ptr(*p, paths->persistent_config)) { + /* This is the best outcome, let's return it immediately. */ + *state = UNIT_FILE_ENABLED; + return 1; + } + + /* look for global enablement of user units */ + if (scope == UNIT_FILE_USER && path_is_user_config_dir(*p)) { + *state = UNIT_FILE_ENABLED; + return 1; + } + + r = path_is_runtime(paths, *p, false); + if (r < 0) + return r; + if (r > 0) + enabled_in_runtime = true; + else + enabled_at_all = true; + + } else if (same_name_link) { + if (path_equal_ptr(*p, paths->persistent_config)) + same_name_link_config = true; + else { + r = path_is_runtime(paths, *p, false); + if (r < 0) + return r; + if (r > 0) + same_name_link_runtime = true; + } + } + + /* Check if next iteration will be "below" the unit file (either a regular file + * or a symlink), and hence should be ignored */ + if (!ignore_same_name && path_startswith(i->path, *p)) + ignore_same_name = true; + } + + if (enabled_in_runtime) { + *state = UNIT_FILE_ENABLED_RUNTIME; + return 1; + } + + /* Here's a special rule: if the unit we are looking for is an instance, and it symlinked in the search path + * outside of runtime and configuration directory, then we consider it statically enabled. Note we do that only + * for instance, not for regular names, as those are merely aliases, while instances explicitly instantiate + * something, and hence are a much stronger concept. */ + if (enabled_at_all && unit_name_is_valid(i->name, UNIT_NAME_INSTANCE)) { + *state = UNIT_FILE_STATIC; + return 1; + } + + /* Hmm, we didn't find it, but maybe we found the same name + * link? */ + if (same_name_link_config) { + *state = UNIT_FILE_LINKED; + return 1; + } + if (same_name_link_runtime) { + *state = UNIT_FILE_LINKED_RUNTIME; + return 1; + } + + return 0; +} + +static void install_info_free(UnitFileInstallInfo *i) { + + if (!i) + return; + + free(i->name); + free(i->path); + strv_free(i->aliases); + strv_free(i->wanted_by); + strv_free(i->required_by); + strv_free(i->also); + free(i->default_instance); + free(i->symlink_target); + free(i); +} + +static void install_context_done(InstallContext *c) { + assert(c); + + c->will_process = ordered_hashmap_free_with_destructor(c->will_process, install_info_free); + c->have_processed = ordered_hashmap_free_with_destructor(c->have_processed, install_info_free); +} + +static UnitFileInstallInfo *install_info_find(InstallContext *c, const char *name) { + UnitFileInstallInfo *i; + + i = ordered_hashmap_get(c->have_processed, name); + if (i) + return i; + + return ordered_hashmap_get(c->will_process, name); +} + +static int install_info_may_process( + const UnitFileInstallInfo *i, + const LookupPaths *paths, + UnitFileChange **changes, + size_t *n_changes) { + assert(i); + assert(paths); + + /* Checks whether the loaded unit file is one we should process, or is masked, + * transient or generated and thus not subject to enable/disable operations. */ + + if (i->type == UNIT_FILE_TYPE_MASKED) { + unit_file_changes_add(changes, n_changes, -ERFKILL, i->path, NULL); + return -ERFKILL; + } + if (path_is_generator(paths, i->path) || + path_is_transient(paths, i->path)) { + unit_file_changes_add(changes, n_changes, -EADDRNOTAVAIL, i->path, NULL); + return -EADDRNOTAVAIL; + } + + return 0; +} + +/** + * Adds a new UnitFileInstallInfo entry under name in the InstallContext.will_process + * hashmap, or retrieves the existing one if already present. + * + * Returns negative on error, 0 if the unit was already known, 1 otherwise. + */ +static int install_info_add( + InstallContext *c, + const char *name, + const char *path, + bool auxiliary, + UnitFileInstallInfo **ret) { + + UnitFileInstallInfo *i = NULL; + int r; + + assert(c); + + if (!name) { + /* 'name' and 'path' must not both be null. Check here 'path' using assert_se() to + * workaround a bug in gcc that generates a -Wnonnull warning when calling basename(), + * but this cannot be possible in any code path (See #6119). */ + assert_se(path); + name = basename(path); + } + + if (!unit_name_is_valid(name, UNIT_NAME_ANY)) + return -EINVAL; + + i = install_info_find(c, name); + if (i) { + i->auxiliary = i->auxiliary && auxiliary; + + if (ret) + *ret = i; + return 0; + } + + r = ordered_hashmap_ensure_allocated(&c->will_process, &string_hash_ops); + if (r < 0) + return r; + + i = new(UnitFileInstallInfo, 1); + if (!i) + return -ENOMEM; + + *i = (UnitFileInstallInfo) { + .type = _UNIT_FILE_TYPE_INVALID, + .auxiliary = auxiliary, + }; + + i->name = strdup(name); + if (!i->name) { + r = -ENOMEM; + goto fail; + } + + if (path) { + i->path = strdup(path); + if (!i->path) { + r = -ENOMEM; + goto fail; + } + } + + r = ordered_hashmap_put(c->will_process, i->name, i); + if (r < 0) + goto fail; + + if (ret) + *ret = i; + + return 1; + +fail: + install_info_free(i); + return r; +} + +static int config_parse_alias( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + UnitType type; + + assert(unit); + assert(filename); + assert(lvalue); + assert(rvalue); + + type = unit_name_to_type(unit); + if (!unit_type_may_alias(type)) + return log_syntax(unit, LOG_WARNING, filename, line, 0, + "Alias= is not allowed for %s units, ignoring.", + unit_type_to_string(type)); + + return config_parse_strv(unit, filename, line, section, section_line, + lvalue, ltype, rvalue, data, userdata); +} + +static int config_parse_also( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + UnitFileInstallInfo *info = userdata; + InstallContext *c = data; + int r; + + assert(unit); + assert(filename); + assert(lvalue); + assert(rvalue); + + for (;;) { + _cleanup_free_ char *word = NULL, *printed = NULL; + + r = extract_first_word(&rvalue, &word, NULL, 0); + if (r < 0) + return r; + if (r == 0) + break; + + r = install_full_printf(info, word, &printed); + if (r < 0) + return r; + + r = install_info_add(c, printed, NULL, true, NULL); + if (r < 0) + return r; + + r = strv_push(&info->also, printed); + if (r < 0) + return r; + + printed = NULL; + } + + return 0; +} + +static int config_parse_default_instance( + const char *unit, + const char *filename, + unsigned line, + const char *section, + unsigned section_line, + const char *lvalue, + int ltype, + const char *rvalue, + void *data, + void *userdata) { + + UnitFileInstallInfo *i = data; + _cleanup_free_ char *printed = NULL; + int r; + + assert(unit); + assert(filename); + assert(lvalue); + assert(rvalue); + + if (unit_name_is_valid(unit, UNIT_NAME_INSTANCE)) + /* When enabling an instance, we might be using a template unit file, + * but we should ignore DefaultInstance silently. */ + return 0; + if (!unit_name_is_valid(unit, UNIT_NAME_TEMPLATE)) + return log_syntax(unit, LOG_WARNING, filename, line, 0, + "DefaultInstance= only makes sense for template units, ignoring."); + + r = install_full_printf(i, rvalue, &printed); + if (r < 0) + return r; + + if (isempty(printed)) { + i->default_instance = mfree(i->default_instance); + return 0; + } + + if (!unit_instance_is_valid(printed)) + return log_syntax(unit, LOG_WARNING, filename, line, SYNTHETIC_ERRNO(EINVAL), + "Invalid DefaultInstance= value \"%s\".", printed); + + return free_and_replace(i->default_instance, printed); +} + +static int unit_file_load( + InstallContext *c, + UnitFileInstallInfo *info, + const char *path, + const char *root_dir, + SearchFlags flags) { + + const ConfigTableItem items[] = { + { "Install", "Alias", config_parse_alias, 0, &info->aliases }, + { "Install", "WantedBy", config_parse_strv, 0, &info->wanted_by }, + { "Install", "RequiredBy", config_parse_strv, 0, &info->required_by }, + { "Install", "DefaultInstance", config_parse_default_instance, 0, info }, + { "Install", "Also", config_parse_also, 0, c }, + {} + }; + + UnitType type; + _cleanup_fclose_ FILE *f = NULL; + _cleanup_close_ int fd = -1; + struct stat st; + int r; + + assert(info); + assert(path); + + if (!(flags & SEARCH_DROPIN)) { + /* Loading or checking for the main unit file… */ + + type = unit_name_to_type(info->name); + if (type < 0) + return -EINVAL; + if (unit_name_is_valid(info->name, UNIT_NAME_TEMPLATE|UNIT_NAME_INSTANCE) && !unit_type_may_template(type)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "%s: unit type %s cannot be templated, ignoring.", path, unit_type_to_string(type)); + + if (!(flags & SEARCH_LOAD)) { + if (lstat(path, &st) < 0) + return -errno; + + if (null_or_empty(&st)) + info->type = UNIT_FILE_TYPE_MASKED; + else if (S_ISREG(st.st_mode)) + info->type = UNIT_FILE_TYPE_REGULAR; + else if (S_ISLNK(st.st_mode)) + return -ELOOP; + else if (S_ISDIR(st.st_mode)) + return -EISDIR; + else + return -ENOTTY; + + return 0; + } + + fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); + if (fd < 0) + return -errno; + } else { + /* Operating on a drop-in file. If we aren't supposed to load the unit file drop-ins don't matter, let's hence shortcut this. */ + + if (!(flags & SEARCH_LOAD)) + return 0; + + fd = chase_symlinks_and_open(path, root_dir, 0, O_RDONLY|O_CLOEXEC|O_NOCTTY, NULL); + if (fd < 0) + return fd; + } + + if (fstat(fd, &st) < 0) + return -errno; + + if (null_or_empty(&st)) { + if ((flags & SEARCH_DROPIN) == 0) + info->type = UNIT_FILE_TYPE_MASKED; + + return 0; + } + + r = stat_verify_regular(&st); + if (r < 0) + return r; + + f = take_fdopen(&fd, "r"); + if (!f) + return -errno; + + /* c is only needed if we actually load the file (it's referenced from items[] btw, in case you wonder.) */ + assert(c); + + r = config_parse(info->name, path, f, + "Install\0" + "-Unit\0" + "-Automount\0" + "-Device\0" + "-Mount\0" + "-Path\0" + "-Scope\0" + "-Service\0" + "-Slice\0" + "-Socket\0" + "-Swap\0" + "-Target\0" + "-Timer\0", + config_item_table_lookup, items, + 0, info, + NULL); + if (r < 0) + return log_debug_errno(r, "Failed to parse %s: %m", info->name); + + if ((flags & SEARCH_DROPIN) == 0) + info->type = UNIT_FILE_TYPE_REGULAR; + + return + (int) strv_length(info->aliases) + + (int) strv_length(info->wanted_by) + + (int) strv_length(info->required_by); +} + +static int unit_file_load_or_readlink( + InstallContext *c, + UnitFileInstallInfo *info, + const char *path, + const char *root_dir, + SearchFlags flags) { + _cleanup_free_ char *resolved = NULL; + struct stat st; + int r; + + r = unit_file_load(c, info, path, root_dir, flags); + if (r != -ELOOP || (flags & SEARCH_DROPIN)) + return r; + + r = chase_symlinks(path, root_dir, CHASE_WARN | CHASE_NONEXISTENT, &resolved, NULL); + if (r >= 0 && + root_dir && + path_equal_ptr(path_startswith(resolved, root_dir), "dev/null")) + /* When looking under root_dir, we can't expect /dev/ to be mounted, + * so let's see if the path is a (possibly dangling) symlink to /dev/null. */ + info->type = UNIT_FILE_TYPE_MASKED; + + else if (r > 0 && + stat(resolved, &st) >= 0 && + null_or_empty(&st)) + + info->type = UNIT_FILE_TYPE_MASKED; + + else { + _cleanup_free_ char *target = NULL; + const char *bn; + UnitType a, b; + + /* This is a symlink, let's read it. We read the link again, because last time + * we followed the link until resolution, and here we need to do one step. */ + + r = readlink_malloc(path, &target); + if (r < 0) + return r; + + bn = basename(target); + + if (unit_name_is_valid(info->name, UNIT_NAME_PLAIN)) { + + if (!unit_name_is_valid(bn, UNIT_NAME_PLAIN)) + return -EINVAL; + + } else if (unit_name_is_valid(info->name, UNIT_NAME_INSTANCE)) { + + if (!unit_name_is_valid(bn, UNIT_NAME_INSTANCE|UNIT_NAME_TEMPLATE)) + return -EINVAL; + + } else if (unit_name_is_valid(info->name, UNIT_NAME_TEMPLATE)) { + + if (!unit_name_is_valid(bn, UNIT_NAME_TEMPLATE)) + return -EINVAL; + } else + return -EINVAL; + + /* Enforce that the symlink destination does not + * change the unit file type. */ + + a = unit_name_to_type(info->name); + b = unit_name_to_type(bn); + if (a < 0 || b < 0 || a != b) + return -EINVAL; + + if (path_is_absolute(target)) + /* This is an absolute path, prefix the root so that we always deal with fully qualified paths */ + info->symlink_target = path_join(root_dir, target); + else + /* This is a relative path, take it relative to the dir the symlink is located in. */ + info->symlink_target = file_in_same_dir(path, target); + if (!info->symlink_target) + return -ENOMEM; + + info->type = UNIT_FILE_TYPE_SYMLINK; + } + + return 0; +} + +static int unit_file_search( + InstallContext *c, + UnitFileInstallInfo *info, + const LookupPaths *paths, + SearchFlags flags) { + + const char *dropin_dir_name = NULL, *dropin_template_dir_name = NULL; + _cleanup_strv_free_ char **dirs = NULL, **files = NULL; + _cleanup_free_ char *template = NULL; + bool found_unit = false; + int r, result; + char **p; + + assert(info); + assert(paths); + + /* Was this unit already loaded? */ + if (info->type != _UNIT_FILE_TYPE_INVALID) + return 0; + + if (info->path) + return unit_file_load_or_readlink(c, info, info->path, paths->root_dir, flags); + + assert(info->name); + + if (unit_name_is_valid(info->name, UNIT_NAME_INSTANCE)) { + r = unit_name_template(info->name, &template); + if (r < 0) + return r; + } + + STRV_FOREACH(p, paths->search_path) { + _cleanup_free_ char *path = NULL; + + path = path_join(*p, info->name); + if (!path) + return -ENOMEM; + + r = unit_file_load_or_readlink(c, info, path, paths->root_dir, flags); + if (r >= 0) { + info->path = TAKE_PTR(path); + result = r; + found_unit = true; + break; + } else if (!IN_SET(r, -ENOENT, -ENOTDIR, -EACCES)) + return r; + } + + if (!found_unit && template) { + + /* Unit file doesn't exist, however instance + * enablement was requested. We will check if it is + * possible to load template unit file. */ + + STRV_FOREACH(p, paths->search_path) { + _cleanup_free_ char *path = NULL; + + path = path_join(*p, template); + if (!path) + return -ENOMEM; + + r = unit_file_load_or_readlink(c, info, path, paths->root_dir, flags); + if (r >= 0) { + info->path = TAKE_PTR(path); + result = r; + found_unit = true; + break; + } else if (!IN_SET(r, -ENOENT, -ENOTDIR, -EACCES)) + return r; + } + } + + if (!found_unit) + return log_debug_errno(SYNTHETIC_ERRNO(ENOENT), + "Cannot find unit %s%s%s.", + info->name, template ? " or " : "", strempty(template)); + + if (info->type == UNIT_FILE_TYPE_MASKED) + return result; + + /* Search for drop-in directories */ + + dropin_dir_name = strjoina(info->name, ".d"); + STRV_FOREACH(p, paths->search_path) { + char *path; + + path = path_join(*p, dropin_dir_name); + if (!path) + return -ENOMEM; + + r = strv_consume(&dirs, path); + if (r < 0) + return r; + } + + if (template) { + dropin_template_dir_name = strjoina(template, ".d"); + STRV_FOREACH(p, paths->search_path) { + char *path; + + path = path_join(*p, dropin_template_dir_name); + if (!path) + return -ENOMEM; + + r = strv_consume(&dirs, path); + if (r < 0) + return r; + } + } + + /* Load drop-in conf files */ + + r = conf_files_list_strv(&files, ".conf", NULL, 0, (const char**) dirs); + if (r < 0) + return log_debug_errno(r, "Failed to get list of conf files: %m"); + + STRV_FOREACH(p, files) { + r = unit_file_load_or_readlink(c, info, *p, paths->root_dir, flags | SEARCH_DROPIN); + if (r < 0) + return log_debug_errno(r, "Failed to load conf file %s: %m", *p); + } + + return result; +} + +static int install_info_follow( + InstallContext *c, + UnitFileInstallInfo *i, + const char *root_dir, + SearchFlags flags, + bool ignore_different_name) { + + assert(c); + assert(i); + + if (i->type != UNIT_FILE_TYPE_SYMLINK) + return -EINVAL; + if (!i->symlink_target) + return -EINVAL; + + /* If the basename doesn't match, the caller should add a + * complete new entry for this. */ + + if (!ignore_different_name && !streq(basename(i->symlink_target), i->name)) + return -EXDEV; + + free_and_replace(i->path, i->symlink_target); + i->type = _UNIT_FILE_TYPE_INVALID; + + return unit_file_load_or_readlink(c, i, i->path, root_dir, flags); +} + +/** + * Search for the unit file. If the unit name is a symlink, follow the symlink to the + * target, maybe more than once. Propagate the instance name if present. + */ +static int install_info_traverse( + UnitFileScope scope, + InstallContext *c, + const LookupPaths *paths, + UnitFileInstallInfo *start, + SearchFlags flags, + UnitFileInstallInfo **ret) { + + UnitFileInstallInfo *i; + unsigned k = 0; + int r; + + assert(paths); + assert(start); + assert(c); + + r = unit_file_search(c, start, paths, flags); + if (r < 0) + return r; + + i = start; + while (i->type == UNIT_FILE_TYPE_SYMLINK) { + /* Follow the symlink */ + + if (++k > UNIT_FILE_FOLLOW_SYMLINK_MAX) + return -ELOOP; + + if (!(flags & SEARCH_FOLLOW_CONFIG_SYMLINKS)) { + r = path_is_config(paths, i->path, true); + if (r < 0) + return r; + if (r > 0) + return -ELOOP; + } + + r = install_info_follow(c, i, paths->root_dir, flags, false); + if (r == -EXDEV) { + _cleanup_free_ char *buffer = NULL; + const char *bn; + + /* Target has a different name, create a new + * install info object for that, and continue + * with that. */ + + bn = basename(i->symlink_target); + + if (unit_name_is_valid(i->name, UNIT_NAME_INSTANCE) && + unit_name_is_valid(bn, UNIT_NAME_TEMPLATE)) { + + _cleanup_free_ char *instance = NULL; + + r = unit_name_to_instance(i->name, &instance); + if (r < 0) + return r; + + r = unit_name_replace_instance(bn, instance, &buffer); + if (r < 0) + return r; + + if (streq(buffer, i->name)) { + + /* We filled in the instance, and the target stayed the same? If so, then let's + * honour the link as it is. */ + + r = install_info_follow(c, i, paths->root_dir, flags, true); + if (r < 0) + return r; + + continue; + } + + bn = buffer; + } + + r = install_info_add(c, bn, NULL, false, &i); + if (r < 0) + return r; + + /* Try again, with the new target we found. */ + r = unit_file_search(c, i, paths, flags); + if (r == -ENOENT) + /* Translate error code to highlight this specific case */ + return -ENOLINK; + } + + if (r < 0) + return r; + } + + if (ret) + *ret = i; + + return 0; +} + +/** + * Call install_info_add() with name_or_path as the path (if name_or_path starts with "/") + * or the name (otherwise). root_dir is prepended to the path. + */ +static int install_info_add_auto( + InstallContext *c, + const LookupPaths *paths, + const char *name_or_path, + UnitFileInstallInfo **ret) { + + assert(c); + assert(name_or_path); + + if (path_is_absolute(name_or_path)) { + const char *pp; + + pp = prefix_roota(paths->root_dir, name_or_path); + + return install_info_add(c, NULL, pp, false, ret); + } else + return install_info_add(c, name_or_path, NULL, false, ret); +} + +static int install_info_discover( + UnitFileScope scope, + InstallContext *c, + const LookupPaths *paths, + const char *name, + SearchFlags flags, + UnitFileInstallInfo **ret, + UnitFileChange **changes, + size_t *n_changes) { + + UnitFileInstallInfo *i; + int r; + + assert(c); + assert(paths); + assert(name); + + r = install_info_add_auto(c, paths, name, &i); + if (r >= 0) + r = install_info_traverse(scope, c, paths, i, flags, ret); + + if (r < 0) + unit_file_changes_add(changes, n_changes, r, name, NULL); + return r; +} + +static int install_info_discover_and_check( + UnitFileScope scope, + InstallContext *c, + const LookupPaths *paths, + const char *name, + SearchFlags flags, + UnitFileInstallInfo **ret, + UnitFileChange **changes, + size_t *n_changes) { + + int r; + + r = install_info_discover(scope, c, paths, name, flags, ret, changes, n_changes); + if (r < 0) + return r; + + return install_info_may_process(ret ? *ret : NULL, paths, changes, n_changes); +} + +int unit_file_verify_alias(const UnitFileInstallInfo *i, const char *dst, char **ret_dst) { + _cleanup_free_ char *dst_updated = NULL; + int r; + + /* Verify that dst is a valid either a valid alias or a valid .wants/.requires symlink for the target + * unit *i. Return negative on error or if not compatible, zero on success. + * + * ret_dst is set in cases where "instance propagation" happens, i.e. when the instance part is + * inserted into dst. It is not normally set, even on success, so that the caller can easily + * distinguish the case where instance propagation occurred. + */ + + const char *path_alias = strrchr(dst, '/'); + if (path_alias) { + /* This branch covers legacy Alias= function of creating .wants and .requires symlinks. */ + _cleanup_free_ char *dir = NULL; + char *p; + + path_alias ++; /* skip over slash */ + + dir = dirname_malloc(dst); + if (!dir) + return log_oom(); + + p = endswith(dir, ".wants"); + if (!p) + p = endswith(dir, ".requires"); + if (!p) + return log_warning_errno(SYNTHETIC_ERRNO(EXDEV), + "Invalid path \"%s\" in alias.", dir); + *p = '\0'; /* dir should now be a unit name */ + + r = unit_name_classify(dir); + if (r < 0) + return log_warning_errno(SYNTHETIC_ERRNO(EXDEV), + "Invalid unit name component \"%s\" in alias.", dir); + + const bool instance_propagation = r == UNIT_NAME_TEMPLATE; + + /* That's the name we want to use for verification. */ + r = unit_symlink_name_compatible(path_alias, i->name, instance_propagation); + if (r < 0) + return log_error_errno(r, "Failed to verify alias validity: %m"); + if (r == 0) + return log_warning_errno(SYNTHETIC_ERRNO(EXDEV), + "Invalid unit %s symlink %s.", + i->name, dst); + + } else { + /* If the symlink target has an instance set and the symlink source doesn't, we "propagate + * the instance", i.e. instantiate the symlink source with the target instance. */ + if (unit_name_is_valid(dst, UNIT_NAME_TEMPLATE)) { + _cleanup_free_ char *inst = NULL; + + r = unit_name_to_instance(i->name, &inst); + if (r < 0) + return log_error_errno(r, "Failed to extract instance name from %s: %m", i->name); + + if (r == UNIT_NAME_INSTANCE) { + r = unit_name_replace_instance(dst, inst, &dst_updated); + if (r < 0) + return log_error_errno(r, "Failed to build unit name from %s+%s: %m", + dst, inst); + } + } + + r = unit_validate_alias_symlink_and_warn(dst_updated ?: dst, i->name); + if (r < 0) + return r; + + } + + *ret_dst = TAKE_PTR(dst_updated); + return 0; +} + +static int install_info_symlink_alias( + UnitFileInstallInfo *i, + const LookupPaths *paths, + const char *config_path, + bool force, + UnitFileChange **changes, + size_t *n_changes) { + + char **s; + int r = 0, q; + + assert(i); + assert(paths); + assert(config_path); + + STRV_FOREACH(s, i->aliases) { + _cleanup_free_ char *alias_path = NULL, *dst = NULL, *dst_updated = NULL; + + q = install_full_printf(i, *s, &dst); + if (q < 0) + return q; + + q = unit_file_verify_alias(i, dst, &dst_updated); + if (q < 0) + continue; + + alias_path = path_make_absolute(dst_updated ?: dst, config_path); + if (!alias_path) + return -ENOMEM; + + q = create_symlink(paths, i->path, alias_path, force, changes, n_changes); + if (r == 0) + r = q; + } + + return r; +} + +static int install_info_symlink_wants( + UnitFileInstallInfo *i, + const LookupPaths *paths, + const char *config_path, + char **list, + const char *suffix, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_free_ char *buf = NULL; + const char *n; + char **s; + int r = 0, q; + + assert(i); + assert(paths); + assert(config_path); + + if (strv_isempty(list)) + return 0; + + if (unit_name_is_valid(i->name, UNIT_NAME_TEMPLATE)) { + UnitFileInstallInfo instance = { + .type = _UNIT_FILE_TYPE_INVALID, + }; + _cleanup_free_ char *path = NULL; + + /* If this is a template, and we have no instance, don't do anything */ + if (!i->default_instance) + return 1; + + r = unit_name_replace_instance(i->name, i->default_instance, &buf); + if (r < 0) + return r; + + instance.name = buf; + r = unit_file_search(NULL, &instance, paths, SEARCH_FOLLOW_CONFIG_SYMLINKS); + if (r < 0) + return r; + + path = TAKE_PTR(instance.path); + + if (instance.type == UNIT_FILE_TYPE_MASKED) { + unit_file_changes_add(changes, n_changes, -ERFKILL, path, NULL); + return -ERFKILL; + } + + n = buf; + } else + n = i->name; + + STRV_FOREACH(s, list) { + _cleanup_free_ char *path = NULL, *dst = NULL; + + q = install_full_printf(i, *s, &dst); + if (q < 0) + return q; + + if (!unit_name_is_valid(dst, UNIT_NAME_ANY)) { + unit_file_changes_add(changes, n_changes, -EUCLEAN, dst, NULL); + r = -EUCLEAN; + continue; + } + + path = strjoin(config_path, "/", dst, suffix, n); + if (!path) + return -ENOMEM; + + q = create_symlink(paths, i->path, path, true, changes, n_changes); + if (r == 0) + r = q; + } + + return r; +} + +static int install_info_symlink_link( + UnitFileInstallInfo *i, + const LookupPaths *paths, + const char *config_path, + bool force, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_free_ char *path = NULL; + int r; + + assert(i); + assert(paths); + assert(config_path); + assert(i->path); + + r = in_search_path(paths, i->path); + if (r < 0) + return r; + if (r > 0) + return 0; + + path = path_join(config_path, i->name); + if (!path) + return -ENOMEM; + + return create_symlink(paths, i->path, path, force, changes, n_changes); +} + +static int install_info_apply( + UnitFileInstallInfo *i, + const LookupPaths *paths, + const char *config_path, + bool force, + UnitFileChange **changes, + size_t *n_changes) { + + int r, q; + + assert(i); + assert(paths); + assert(config_path); + + if (i->type != UNIT_FILE_TYPE_REGULAR) + return 0; + + r = install_info_symlink_alias(i, paths, config_path, force, changes, n_changes); + + q = install_info_symlink_wants(i, paths, config_path, i->wanted_by, ".wants/", changes, n_changes); + if (r == 0) + r = q; + + q = install_info_symlink_wants(i, paths, config_path, i->required_by, ".requires/", changes, n_changes); + if (r == 0) + r = q; + + q = install_info_symlink_link(i, paths, config_path, force, changes, n_changes); + /* Do not count links to the unit file towards the "carries_install_info" count */ + if (r == 0 && q < 0) + r = q; + + return r; +} + +static int install_context_apply( + UnitFileScope scope, + InstallContext *c, + const LookupPaths *paths, + const char *config_path, + bool force, + SearchFlags flags, + UnitFileChange **changes, + size_t *n_changes) { + + UnitFileInstallInfo *i; + int r; + + assert(c); + assert(paths); + assert(config_path); + + if (ordered_hashmap_isempty(c->will_process)) + return 0; + + r = ordered_hashmap_ensure_allocated(&c->have_processed, &string_hash_ops); + if (r < 0) + return r; + + r = 0; + while ((i = ordered_hashmap_first(c->will_process))) { + int q; + + q = ordered_hashmap_move_one(c->have_processed, c->will_process, i->name); + if (q < 0) + return q; + + q = install_info_traverse(scope, c, paths, i, flags, NULL); + if (q < 0) { + unit_file_changes_add(changes, n_changes, q, i->name, NULL); + return q; + } + + /* We can attempt to process a masked unit when a different unit + * that we were processing specifies it in Also=. */ + if (i->type == UNIT_FILE_TYPE_MASKED) { + unit_file_changes_add(changes, n_changes, UNIT_FILE_IS_MASKED, i->path, NULL); + if (r >= 0) + /* Assume that something *could* have been enabled here, + * avoid "empty [Install] section" warning. */ + r += 1; + continue; + } + + if (i->type != UNIT_FILE_TYPE_REGULAR) + continue; + + q = install_info_apply(i, paths, config_path, force, changes, n_changes); + if (r >= 0) { + if (q < 0) + r = q; + else + r += q; + } + } + + return r; +} + +static int install_context_mark_for_removal( + UnitFileScope scope, + InstallContext *c, + const LookupPaths *paths, + Set **remove_symlinks_to, + const char *config_path, + UnitFileChange **changes, + size_t *n_changes) { + + UnitFileInstallInfo *i; + int r; + + assert(c); + assert(paths); + assert(config_path); + + /* Marks all items for removal */ + + if (ordered_hashmap_isempty(c->will_process)) + return 0; + + r = ordered_hashmap_ensure_allocated(&c->have_processed, &string_hash_ops); + if (r < 0) + return r; + + while ((i = ordered_hashmap_first(c->will_process))) { + + r = ordered_hashmap_move_one(c->have_processed, c->will_process, i->name); + if (r < 0) + return r; + + r = install_info_traverse(scope, c, paths, i, SEARCH_LOAD|SEARCH_FOLLOW_CONFIG_SYMLINKS, NULL); + if (r == -ENOLINK) { + log_debug_errno(r, "Name %s leads to a dangling symlink, removing name.", i->name); + unit_file_changes_add(changes, n_changes, UNIT_FILE_IS_DANGLING, i->path ?: i->name, NULL); + } else if (r == -ENOENT) { + + if (i->auxiliary) /* some unit specified in Also= or similar is missing */ + log_debug_errno(r, "Auxiliary unit of %s not found, removing name.", i->name); + else { + log_debug_errno(r, "Unit %s not found, removing name.", i->name); + unit_file_changes_add(changes, n_changes, r, i->path ?: i->name, NULL); + } + + } else if (r < 0) { + log_debug_errno(r, "Failed to find unit %s, removing name: %m", i->name); + unit_file_changes_add(changes, n_changes, r, i->path ?: i->name, NULL); + } else if (i->type == UNIT_FILE_TYPE_MASKED) { + log_debug("Unit file %s is masked, ignoring.", i->name); + unit_file_changes_add(changes, n_changes, UNIT_FILE_IS_MASKED, i->path ?: i->name, NULL); + continue; + } else if (i->type != UNIT_FILE_TYPE_REGULAR) { + log_debug("Unit %s has type %s, ignoring.", i->name, unit_file_type_to_string(i->type) ?: "invalid"); + continue; + } + + r = mark_symlink_for_removal(remove_symlinks_to, i->name); + if (r < 0) + return r; + } + + return 0; +} + +int unit_file_mask( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + char **files, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + const char *config_path; + char **i; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + config_path = (flags & UNIT_FILE_RUNTIME) ? paths.runtime_config : paths.persistent_config; + if (!config_path) + return -ENXIO; + + STRV_FOREACH(i, files) { + _cleanup_free_ char *path = NULL; + int q; + + if (!unit_name_is_valid(*i, UNIT_NAME_ANY)) { + if (r == 0) + r = -EINVAL; + continue; + } + + path = path_make_absolute(*i, config_path); + if (!path) + return -ENOMEM; + + q = create_symlink(&paths, "/dev/null", path, !!(flags & UNIT_FILE_FORCE), changes, n_changes); + if (q < 0 && r >= 0) + r = q; + } + + return r; +} + +int unit_file_unmask( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + char **files, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_set_free_free_ Set *remove_symlinks_to = NULL; + _cleanup_strv_free_ char **todo = NULL; + size_t n_todo = 0, n_allocated = 0; + const char *config_path; + char **i; + bool dry_run; + int r, q; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + config_path = (flags & UNIT_FILE_RUNTIME) ? paths.runtime_config : paths.persistent_config; + if (!config_path) + return -ENXIO; + + dry_run = !!(flags & UNIT_FILE_DRY_RUN); + + STRV_FOREACH(i, files) { + _cleanup_free_ char *path = NULL; + + if (!unit_name_is_valid(*i, UNIT_NAME_ANY)) + return -EINVAL; + + path = path_make_absolute(*i, config_path); + if (!path) + return -ENOMEM; + + r = null_or_empty_path(path); + if (r == -ENOENT) + continue; + if (r < 0) + return r; + if (r == 0) + continue; + + if (!GREEDY_REALLOC0(todo, n_allocated, n_todo + 2)) + return -ENOMEM; + + todo[n_todo] = strdup(*i); + if (!todo[n_todo]) + return -ENOMEM; + + n_todo++; + } + + strv_uniq(todo); + + r = 0; + STRV_FOREACH(i, todo) { + _cleanup_free_ char *path = NULL; + const char *rp; + + path = path_make_absolute(*i, config_path); + if (!path) + return -ENOMEM; + + if (!dry_run && unlink(path) < 0) { + if (errno != ENOENT) { + if (r >= 0) + r = -errno; + unit_file_changes_add(changes, n_changes, -errno, path, NULL); + } + + continue; + } + + unit_file_changes_add(changes, n_changes, UNIT_FILE_UNLINK, path, NULL); + + rp = skip_root(&paths, path); + q = mark_symlink_for_removal(&remove_symlinks_to, rp ?: path); + if (q < 0) + return q; + } + + q = remove_marked_symlinks(remove_symlinks_to, config_path, &paths, dry_run, changes, n_changes); + if (r >= 0) + r = q; + + return r; +} + +int unit_file_link( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + char **files, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_strv_free_ char **todo = NULL; + size_t n_todo = 0, n_allocated = 0; + const char *config_path; + char **i; + int r, q; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + config_path = (flags & UNIT_FILE_RUNTIME) ? paths.runtime_config : paths.persistent_config; + if (!config_path) + return -ENXIO; + + STRV_FOREACH(i, files) { + _cleanup_free_ char *full = NULL; + struct stat st; + char *fn; + + if (!path_is_absolute(*i)) + return -EINVAL; + + fn = basename(*i); + if (!unit_name_is_valid(fn, UNIT_NAME_ANY)) + return -EINVAL; + + full = path_join(paths.root_dir, *i); + if (!full) + return -ENOMEM; + + if (lstat(full, &st) < 0) + return -errno; + r = stat_verify_regular(&st); + if (r < 0) + return r; + + q = in_search_path(&paths, *i); + if (q < 0) + return q; + if (q > 0) + continue; + + if (!GREEDY_REALLOC0(todo, n_allocated, n_todo + 2)) + return -ENOMEM; + + todo[n_todo] = strdup(*i); + if (!todo[n_todo]) + return -ENOMEM; + + n_todo++; + } + + strv_uniq(todo); + + r = 0; + STRV_FOREACH(i, todo) { + _cleanup_free_ char *new_path = NULL; + + new_path = path_make_absolute(basename(*i), config_path); + if (!new_path) + return -ENOMEM; + + q = create_symlink(&paths, *i, new_path, !!(flags & UNIT_FILE_FORCE), changes, n_changes); + if (q < 0 && r >= 0) + r = q; + } + + return r; +} + +static int path_shall_revert(const LookupPaths *paths, const char *path) { + int r; + + assert(paths); + assert(path); + + /* Checks whether the path is one where the drop-in directories shall be removed. */ + + r = path_is_config(paths, path, true); + if (r != 0) + return r; + + r = path_is_control(paths, path); + if (r != 0) + return r; + + return path_is_transient(paths, path); +} + +int unit_file_revert( + UnitFileScope scope, + const char *root_dir, + char **files, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_set_free_free_ Set *remove_symlinks_to = NULL; + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_strv_free_ char **todo = NULL; + size_t n_todo = 0, n_allocated = 0; + char **i; + int r, q; + + /* Puts a unit file back into vendor state. This means: + * + * a) we remove all drop-in snippets added by the user ("config"), add to transient units ("transient"), and + * added via "systemctl set-property" ("control"), but not if the drop-in is generated ("generated"). + * + * c) if there's a vendor unit file (i.e. one in /usr) we remove any configured overriding unit files (i.e. in + * "config", but not in "transient" or "control" or even "generated"). + * + * We remove all that in both the runtime and the persistent directories, if that applies. + */ + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + STRV_FOREACH(i, files) { + bool has_vendor = false; + char **p; + + if (!unit_name_is_valid(*i, UNIT_NAME_ANY)) + return -EINVAL; + + STRV_FOREACH(p, paths.search_path) { + _cleanup_free_ char *path = NULL, *dropin = NULL; + struct stat st; + + path = path_make_absolute(*i, *p); + if (!path) + return -ENOMEM; + + r = lstat(path, &st); + if (r < 0) { + if (errno != ENOENT) + return -errno; + } else if (S_ISREG(st.st_mode)) { + /* Check if there's a vendor version */ + r = path_is_vendor_or_generator(&paths, path); + if (r < 0) + return r; + if (r > 0) + has_vendor = true; + } + + dropin = strjoin(path, ".d"); + if (!dropin) + return -ENOMEM; + + r = lstat(dropin, &st); + if (r < 0) { + if (errno != ENOENT) + return -errno; + } else if (S_ISDIR(st.st_mode)) { + /* Remove the drop-ins */ + r = path_shall_revert(&paths, dropin); + if (r < 0) + return r; + if (r > 0) { + if (!GREEDY_REALLOC0(todo, n_allocated, n_todo + 2)) + return -ENOMEM; + + todo[n_todo++] = TAKE_PTR(dropin); + } + } + } + + if (!has_vendor) + continue; + + /* OK, there's a vendor version, hence drop all configuration versions */ + STRV_FOREACH(p, paths.search_path) { + _cleanup_free_ char *path = NULL; + struct stat st; + + path = path_make_absolute(*i, *p); + if (!path) + return -ENOMEM; + + r = lstat(path, &st); + if (r < 0) { + if (errno != ENOENT) + return -errno; + } else if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) { + r = path_is_config(&paths, path, true); + if (r < 0) + return r; + if (r > 0) { + if (!GREEDY_REALLOC0(todo, n_allocated, n_todo + 2)) + return -ENOMEM; + + todo[n_todo++] = TAKE_PTR(path); + } + } + } + } + + strv_uniq(todo); + + r = 0; + STRV_FOREACH(i, todo) { + _cleanup_strv_free_ char **fs = NULL; + const char *rp; + char **j; + + (void) get_files_in_directory(*i, &fs); + + q = rm_rf(*i, REMOVE_ROOT|REMOVE_PHYSICAL); + if (q < 0 && q != -ENOENT && r >= 0) { + r = q; + continue; + } + + STRV_FOREACH(j, fs) { + _cleanup_free_ char *t = NULL; + + t = path_join(*i, *j); + if (!t) + return -ENOMEM; + + unit_file_changes_add(changes, n_changes, UNIT_FILE_UNLINK, t, NULL); + } + + unit_file_changes_add(changes, n_changes, UNIT_FILE_UNLINK, *i, NULL); + + rp = skip_root(&paths, *i); + q = mark_symlink_for_removal(&remove_symlinks_to, rp ?: *i); + if (q < 0) + return q; + } + + q = remove_marked_symlinks(remove_symlinks_to, paths.runtime_config, &paths, false, changes, n_changes); + if (r >= 0) + r = q; + + q = remove_marked_symlinks(remove_symlinks_to, paths.persistent_config, &paths, false, changes, n_changes); + if (r >= 0) + r = q; + + return r; +} + +int unit_file_add_dependency( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + char **files, + const char *target, + UnitDependency dep, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_(install_context_done) InstallContext c = {}; + UnitFileInstallInfo *i, *target_info; + const char *config_path; + char **f; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + assert(target); + + if (!IN_SET(dep, UNIT_WANTS, UNIT_REQUIRES)) + return -EINVAL; + + if (!unit_name_is_valid(target, UNIT_NAME_ANY)) + return -EINVAL; + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + config_path = (flags & UNIT_FILE_RUNTIME) ? paths.runtime_config : paths.persistent_config; + if (!config_path) + return -ENXIO; + + r = install_info_discover_and_check(scope, &c, &paths, target, SEARCH_FOLLOW_CONFIG_SYMLINKS, + &target_info, changes, n_changes); + if (r < 0) + return r; + + assert(target_info->type == UNIT_FILE_TYPE_REGULAR); + + STRV_FOREACH(f, files) { + char ***l; + + r = install_info_discover_and_check(scope, &c, &paths, *f, SEARCH_FOLLOW_CONFIG_SYMLINKS, + &i, changes, n_changes); + if (r < 0) + return r; + + assert(i->type == UNIT_FILE_TYPE_REGULAR); + + /* We didn't actually load anything from the unit + * file, but instead just add in our new symlink to + * create. */ + + if (dep == UNIT_WANTS) + l = &i->wanted_by; + else + l = &i->required_by; + + strv_free(*l); + *l = strv_new(target_info->name); + if (!*l) + return -ENOMEM; + } + + return install_context_apply(scope, &c, &paths, config_path, !!(flags & UNIT_FILE_FORCE), SEARCH_FOLLOW_CONFIG_SYMLINKS, changes, n_changes); +} + +int unit_file_enable( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + char **files, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_(install_context_done) InstallContext c = {}; + const char *config_path; + UnitFileInstallInfo *i; + char **f; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + config_path = config_path_from_flags(&paths, flags); + if (!config_path) + return -ENXIO; + + STRV_FOREACH(f, files) { + r = install_info_discover_and_check(scope, &c, &paths, *f, SEARCH_LOAD|SEARCH_FOLLOW_CONFIG_SYMLINKS, + &i, changes, n_changes); + if (r < 0) + return r; + + assert(i->type == UNIT_FILE_TYPE_REGULAR); + } + + /* This will return the number of symlink rules that were + supposed to be created, not the ones actually created. This + is useful to determine whether the passed files had any + installation data at all. */ + + return install_context_apply(scope, &c, &paths, config_path, !!(flags & UNIT_FILE_FORCE), SEARCH_LOAD, changes, n_changes); +} + +int unit_file_disable( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + char **files, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_(install_context_done) InstallContext c = {}; + _cleanup_set_free_free_ Set *remove_symlinks_to = NULL; + const char *config_path; + char **i; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + config_path = config_path_from_flags(&paths, flags); + if (!config_path) + return -ENXIO; + + STRV_FOREACH(i, files) { + if (!unit_name_is_valid(*i, UNIT_NAME_ANY)) + return -EINVAL; + + r = install_info_add(&c, *i, NULL, false, NULL); + if (r < 0) + return r; + } + + r = install_context_mark_for_removal(scope, &c, &paths, &remove_symlinks_to, config_path, changes, n_changes); + if (r < 0) + return r; + + return remove_marked_symlinks(remove_symlinks_to, config_path, &paths, !!(flags & UNIT_FILE_DRY_RUN), changes, n_changes); +} + +int unit_file_reenable( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + char **files, + UnitFileChange **changes, + size_t *n_changes) { + + char **n; + int r; + size_t l, i; + + /* First, we invoke the disable command with only the basename... */ + l = strv_length(files); + n = newa(char*, l+1); + for (i = 0; i < l; i++) + n[i] = basename(files[i]); + n[i] = NULL; + + r = unit_file_disable(scope, flags, root_dir, n, changes, n_changes); + if (r < 0) + return r; + + /* But the enable command with the full name */ + return unit_file_enable(scope, flags, root_dir, files, changes, n_changes); +} + +int unit_file_set_default( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + const char *name, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_(install_context_done) InstallContext c = {}; + UnitFileInstallInfo *i; + const char *new_path; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + assert(name); + + if (unit_name_to_type(name) != UNIT_TARGET) /* this also validates the name */ + return -EINVAL; + if (streq(name, SPECIAL_DEFAULT_TARGET)) + return -EINVAL; + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + r = install_info_discover_and_check(scope, &c, &paths, name, 0, &i, changes, n_changes); + if (r < 0) + return r; + + new_path = strjoina(paths.persistent_config, "/" SPECIAL_DEFAULT_TARGET); + return create_symlink(&paths, i->path, new_path, !!(flags & UNIT_FILE_FORCE), changes, n_changes); +} + +int unit_file_get_default( + UnitFileScope scope, + const char *root_dir, + char **name) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_(install_context_done) InstallContext c = {}; + UnitFileInstallInfo *i; + char *n; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + assert(name); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + r = install_info_discover(scope, &c, &paths, SPECIAL_DEFAULT_TARGET, SEARCH_FOLLOW_CONFIG_SYMLINKS, + &i, NULL, NULL); + if (r < 0) + return r; + r = install_info_may_process(i, &paths, NULL, 0); + if (r < 0) + return r; + + n = strdup(i->name); + if (!n) + return -ENOMEM; + + *name = n; + return 0; +} + +int unit_file_lookup_state( + UnitFileScope scope, + const LookupPaths *paths, + const char *name, + UnitFileState *ret) { + + _cleanup_(install_context_done) InstallContext c = {}; + UnitFileInstallInfo *i; + UnitFileState state; + int r; + + assert(paths); + assert(name); + + if (!unit_name_is_valid(name, UNIT_NAME_ANY)) + return -EINVAL; + + r = install_info_discover(scope, &c, paths, name, SEARCH_LOAD|SEARCH_FOLLOW_CONFIG_SYMLINKS, + &i, NULL, NULL); + if (r < 0) + return log_debug_errno(r, "Failed to discover unit %s: %m", name); + + assert(IN_SET(i->type, UNIT_FILE_TYPE_REGULAR, UNIT_FILE_TYPE_MASKED)); + log_debug("Found unit %s at %s (%s)", name, strna(i->path), + i->type == UNIT_FILE_TYPE_REGULAR ? "regular file" : "mask"); + + /* Shortcut things, if the caller just wants to know if this unit exists. */ + if (!ret) + return 0; + + switch (i->type) { + + case UNIT_FILE_TYPE_MASKED: + r = path_is_runtime(paths, i->path, true); + if (r < 0) + return r; + + state = r > 0 ? UNIT_FILE_MASKED_RUNTIME : UNIT_FILE_MASKED; + break; + + case UNIT_FILE_TYPE_REGULAR: + /* Check if the name we were querying is actually an alias */ + if (!streq(name, basename(i->path)) && !unit_name_is_valid(i->name, UNIT_NAME_INSTANCE)) { + state = UNIT_FILE_ALIAS; + break; + } + + r = path_is_generator(paths, i->path); + if (r < 0) + return r; + if (r > 0) { + state = UNIT_FILE_GENERATED; + break; + } + + r = path_is_transient(paths, i->path); + if (r < 0) + return r; + if (r > 0) { + state = UNIT_FILE_TRANSIENT; + break; + } + + /* Check if any of the Alias= symlinks have been created. + * We ignore other aliases, and only check those that would + * be created by systemctl enable for this unit. */ + r = find_symlinks_in_scope(scope, paths, i, true, &state); + if (r < 0) + return r; + if (r > 0) + break; + + /* Check if the file is known under other names. If it is, + * it might be in use. Report that as UNIT_FILE_INDIRECT. */ + r = find_symlinks_in_scope(scope, paths, i, false, &state); + if (r < 0) + return r; + if (r > 0) + state = UNIT_FILE_INDIRECT; + else { + if (unit_file_install_info_has_rules(i)) + state = UNIT_FILE_DISABLED; + else if (unit_file_install_info_has_also(i)) + state = UNIT_FILE_INDIRECT; + else + state = UNIT_FILE_STATIC; + } + + break; + + default: + assert_not_reached("Unexpected unit file type."); + } + + *ret = state; + return 0; +} + +int unit_file_get_state( + UnitFileScope scope, + const char *root_dir, + const char *name, + UnitFileState *ret) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + assert(name); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + return unit_file_lookup_state(scope, &paths, name, ret); +} + +int unit_file_exists(UnitFileScope scope, const LookupPaths *paths, const char *name) { + _cleanup_(install_context_done) InstallContext c = {}; + int r; + + assert(paths); + assert(name); + + if (!unit_name_is_valid(name, UNIT_NAME_ANY)) + return -EINVAL; + + r = install_info_discover(scope, &c, paths, name, 0, NULL, NULL, NULL); + if (r == -ENOENT) + return 0; + if (r < 0) + return r; + + return 1; +} + +static int split_pattern_into_name_and_instances(const char *pattern, char **out_unit_name, char ***out_instances) { + _cleanup_strv_free_ char **instances = NULL; + _cleanup_free_ char *unit_name = NULL; + int r; + + assert(pattern); + assert(out_instances); + assert(out_unit_name); + + r = extract_first_word(&pattern, &unit_name, NULL, EXTRACT_RETAIN_ESCAPE); + if (r < 0) + return r; + + /* We handle the instances logic when unit name is extracted */ + if (pattern) { + /* We only create instances when a rule of templated unit + * is seen. A rule like enable foo@.service a b c will + * result in an array of (a, b, c) as instance names */ + if (!unit_name_is_valid(unit_name, UNIT_NAME_TEMPLATE)) + return -EINVAL; + + instances = strv_split(pattern, WHITESPACE); + if (!instances) + return -ENOMEM; + + *out_instances = TAKE_PTR(instances); + } + + *out_unit_name = TAKE_PTR(unit_name); + + return 0; +} + +static int presets_find_config(UnitFileScope scope, const char *root_dir, char ***files) { + static const char* const system_dirs[] = {CONF_PATHS("systemd/system-preset"), NULL}; + static const char* const user_dirs[] = {CONF_PATHS_USR("systemd/user-preset"), NULL}; + const char* const* dirs; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + + if (scope == UNIT_FILE_SYSTEM) + dirs = system_dirs; + else if (IN_SET(scope, UNIT_FILE_GLOBAL, UNIT_FILE_USER)) + dirs = user_dirs; + else + assert_not_reached("Invalid unit file scope"); + + return conf_files_list_strv(files, ".preset", root_dir, 0, dirs); +} + +static int read_presets(UnitFileScope scope, const char *root_dir, UnitFilePresets *presets) { + _cleanup_(unit_file_presets_freep) UnitFilePresets ps = {}; + size_t n_allocated = 0; + _cleanup_strv_free_ char **files = NULL; + char **p; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + assert(presets); + + r = presets_find_config(scope, root_dir, &files); + if (r < 0) + return r; + + STRV_FOREACH(p, files) { + _cleanup_fclose_ FILE *f; + int n = 0; + + f = fopen(*p, "re"); + if (!f) { + if (errno == ENOENT) + continue; + + return -errno; + } + + for (;;) { + _cleanup_free_ char *line = NULL; + UnitFilePresetRule rule = {}; + const char *parameter; + char *l; + + r = read_line(f, LONG_LINE_MAX, &line); + if (r < 0) + return r; + if (r == 0) + break; + + l = strstrip(line); + n++; + + if (isempty(l)) + continue; + if (strchr(COMMENTS, *l)) + continue; + + parameter = first_word(l, "enable"); + if (parameter) { + char *unit_name; + char **instances = NULL; + + /* Unit_name will remain the same as parameter when no instances are specified */ + r = split_pattern_into_name_and_instances(parameter, &unit_name, &instances); + if (r < 0) { + log_syntax(NULL, LOG_WARNING, *p, n, r, "Couldn't parse line '%s'. Ignoring.", line); + continue; + } + + rule = (UnitFilePresetRule) { + .pattern = unit_name, + .action = PRESET_ENABLE, + .instances = instances, + }; + } + + parameter = first_word(l, "disable"); + if (parameter) { + char *pattern; + + pattern = strdup(parameter); + if (!pattern) + return -ENOMEM; + + rule = (UnitFilePresetRule) { + .pattern = pattern, + .action = PRESET_DISABLE, + }; + } + + if (rule.action) { + if (!GREEDY_REALLOC(ps.rules, n_allocated, ps.n_rules + 1)) + return -ENOMEM; + + ps.rules[ps.n_rules++] = rule; + continue; + } + + log_syntax(NULL, LOG_WARNING, *p, n, 0, "Couldn't parse line '%s'. Ignoring.", line); + } + } + + ps.initialized = true; + *presets = ps; + ps = (UnitFilePresets){}; + + return 0; +} + +static int pattern_match_multiple_instances( + const UnitFilePresetRule rule, + const char *unit_name, + char ***ret) { + + _cleanup_free_ char *templated_name = NULL; + int r; + + /* If no ret is needed or the rule itself does not have instances + * initialized, we return not matching */ + if (!ret || !rule.instances) + return 0; + + r = unit_name_template(unit_name, &templated_name); + if (r < 0) + return r; + if (!streq(rule.pattern, templated_name)) + return 0; + + /* Compose a list of specified instances when unit name is a template */ + if (unit_name_is_valid(unit_name, UNIT_NAME_TEMPLATE)) { + _cleanup_strv_free_ char **out_strv = NULL; + + char **iter; + STRV_FOREACH(iter, rule.instances) { + _cleanup_free_ char *name = NULL; + + r = unit_name_replace_instance(unit_name, *iter, &name); + if (r < 0) + return r; + + r = strv_consume(&out_strv, TAKE_PTR(name)); + if (r < 0) + return r; + } + + *ret = TAKE_PTR(out_strv); + return 1; + } else { + /* We now know the input unit name is an instance name */ + _cleanup_free_ char *instance_name = NULL; + + r = unit_name_to_instance(unit_name, &instance_name); + if (r < 0) + return r; + + if (strv_find(rule.instances, instance_name)) + return 1; + } + return 0; +} + +static int query_presets(const char *name, const UnitFilePresets *presets, char ***instance_name_list) { + PresetAction action = PRESET_UNKNOWN; + + if (!unit_name_is_valid(name, UNIT_NAME_ANY)) + return -EINVAL; + + for (size_t i = 0; i < presets->n_rules; i++) + if (pattern_match_multiple_instances(presets->rules[i], name, instance_name_list) > 0 || + fnmatch(presets->rules[i].pattern, name, FNM_NOESCAPE) == 0) { + action = presets->rules[i].action; + break; + } + + switch (action) { + case PRESET_UNKNOWN: + log_debug("Preset files don't specify rule for %s. Enabling.", name); + return 1; + case PRESET_ENABLE: + if (instance_name_list && *instance_name_list) { + char **s; + STRV_FOREACH(s, *instance_name_list) + log_debug("Preset files say enable %s.", *s); + } else + log_debug("Preset files say enable %s.", name); + return 1; + case PRESET_DISABLE: + log_debug("Preset files say disable %s.", name); + return 0; + default: + assert_not_reached("invalid preset action"); + } +} + +int unit_file_query_preset(UnitFileScope scope, const char *root_dir, const char *name, UnitFilePresets *cached) { + _cleanup_(unit_file_presets_freep) UnitFilePresets tmp = {}; + int r; + + if (!cached) + cached = &tmp; + if (!cached->initialized) { + r = read_presets(scope, root_dir, cached); + if (r < 0) + return r; + } + + return query_presets(name, cached, NULL); +} + +static int execute_preset( + UnitFileScope scope, + InstallContext *plus, + InstallContext *minus, + const LookupPaths *paths, + const char *config_path, + char **files, + UnitFilePresetMode mode, + bool force, + UnitFileChange **changes, + size_t *n_changes) { + + int r; + + assert(plus); + assert(minus); + assert(paths); + assert(config_path); + + if (mode != UNIT_FILE_PRESET_ENABLE_ONLY) { + _cleanup_set_free_free_ Set *remove_symlinks_to = NULL; + + r = install_context_mark_for_removal(scope, minus, paths, &remove_symlinks_to, config_path, changes, n_changes); + if (r < 0) + return r; + + r = remove_marked_symlinks(remove_symlinks_to, config_path, paths, false, changes, n_changes); + } else + r = 0; + + if (mode != UNIT_FILE_PRESET_DISABLE_ONLY) { + int q; + + /* Returns number of symlinks that where supposed to be installed. */ + q = install_context_apply(scope, plus, paths, config_path, force, SEARCH_LOAD, changes, n_changes); + if (r >= 0) { + if (q < 0) + r = q; + else + r += q; + } + } + + return r; +} + +static int preset_prepare_one( + UnitFileScope scope, + InstallContext *plus, + InstallContext *minus, + LookupPaths *paths, + const char *name, + const UnitFilePresets *presets, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(install_context_done) InstallContext tmp = {}; + _cleanup_strv_free_ char **instance_name_list = NULL; + UnitFileInstallInfo *i; + int r; + + if (install_info_find(plus, name) || install_info_find(minus, name)) + return 0; + + r = install_info_discover(scope, &tmp, paths, name, SEARCH_FOLLOW_CONFIG_SYMLINKS, + &i, changes, n_changes); + if (r < 0) + return r; + if (!streq(name, i->name)) { + log_debug("Skipping %s because it is an alias for %s.", name, i->name); + return 0; + } + + r = query_presets(name, presets, &instance_name_list); + if (r < 0) + return r; + + if (r > 0) { + if (instance_name_list) { + char **s; + STRV_FOREACH(s, instance_name_list) { + r = install_info_discover_and_check(scope, plus, paths, *s, SEARCH_LOAD|SEARCH_FOLLOW_CONFIG_SYMLINKS, + &i, changes, n_changes); + if (r < 0) + return r; + } + } else { + r = install_info_discover_and_check(scope, plus, paths, name, SEARCH_LOAD|SEARCH_FOLLOW_CONFIG_SYMLINKS, + &i, changes, n_changes); + if (r < 0) + return r; + } + + } else + r = install_info_discover(scope, minus, paths, name, SEARCH_FOLLOW_CONFIG_SYMLINKS, + &i, changes, n_changes); + + return r; +} + +int unit_file_preset( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + char **files, + UnitFilePresetMode mode, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(install_context_done) InstallContext plus = {}, minus = {}; + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_(unit_file_presets_freep) UnitFilePresets presets = {}; + const char *config_path; + char **i; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + assert(mode < _UNIT_FILE_PRESET_MAX); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + config_path = (flags & UNIT_FILE_RUNTIME) ? paths.runtime_config : paths.persistent_config; + if (!config_path) + return -ENXIO; + + r = read_presets(scope, root_dir, &presets); + if (r < 0) + return r; + + STRV_FOREACH(i, files) { + r = preset_prepare_one(scope, &plus, &minus, &paths, *i, &presets, changes, n_changes); + if (r < 0) + return r; + } + + return execute_preset(scope, &plus, &minus, &paths, config_path, files, mode, !!(flags & UNIT_FILE_FORCE), changes, n_changes); +} + +int unit_file_preset_all( + UnitFileScope scope, + UnitFileFlags flags, + const char *root_dir, + UnitFilePresetMode mode, + UnitFileChange **changes, + size_t *n_changes) { + + _cleanup_(install_context_done) InstallContext plus = {}, minus = {}; + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + _cleanup_(unit_file_presets_freep) UnitFilePresets presets = {}; + const char *config_path = NULL; + char **i; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + assert(mode < _UNIT_FILE_PRESET_MAX); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + config_path = (flags & UNIT_FILE_RUNTIME) ? paths.runtime_config : paths.persistent_config; + if (!config_path) + return -ENXIO; + + r = read_presets(scope, root_dir, &presets); + if (r < 0) + return r; + + STRV_FOREACH(i, paths.search_path) { + _cleanup_closedir_ DIR *d = NULL; + struct dirent *de; + + d = opendir(*i); + if (!d) { + if (errno == ENOENT) + continue; + + return -errno; + } + + FOREACH_DIRENT(de, d, return -errno) { + + if (!unit_name_is_valid(de->d_name, UNIT_NAME_ANY)) + continue; + + dirent_ensure_type(d, de); + + if (!IN_SET(de->d_type, DT_LNK, DT_REG)) + continue; + + /* we don't pass changes[] in, because we want to handle errors on our own */ + r = preset_prepare_one(scope, &plus, &minus, &paths, de->d_name, &presets, NULL, 0); + if (r == -ERFKILL) + r = unit_file_changes_add(changes, n_changes, + UNIT_FILE_IS_MASKED, de->d_name, NULL); + else if (r == -ENOLINK) + r = unit_file_changes_add(changes, n_changes, + UNIT_FILE_IS_DANGLING, de->d_name, NULL); + else if (r == -EADDRNOTAVAIL) /* Ignore generated/transient units when applying preset */ + continue; + if (r < 0) + return r; + } + } + + return execute_preset(scope, &plus, &minus, &paths, config_path, NULL, mode, !!(flags & UNIT_FILE_FORCE), changes, n_changes); +} + +static void unit_file_list_free_one(UnitFileList *f) { + if (!f) + return; + + free(f->path); + free(f); +} + +Hashmap* unit_file_list_free(Hashmap *h) { + return hashmap_free_with_destructor(h, unit_file_list_free_one); +} + +DEFINE_TRIVIAL_CLEANUP_FUNC(UnitFileList*, unit_file_list_free_one); + +int unit_file_get_list( + UnitFileScope scope, + const char *root_dir, + Hashmap *h, + char **states, + char **patterns) { + + _cleanup_(lookup_paths_free) LookupPaths paths = {}; + char **dirname; + int r; + + assert(scope >= 0); + assert(scope < _UNIT_FILE_SCOPE_MAX); + assert(h); + + r = lookup_paths_init(&paths, scope, 0, root_dir); + if (r < 0) + return r; + + STRV_FOREACH(dirname, paths.search_path) { + _cleanup_closedir_ DIR *d = NULL; + struct dirent *de; + + d = opendir(*dirname); + if (!d) { + if (errno == ENOENT) + continue; + if (IN_SET(errno, ENOTDIR, EACCES)) { + log_debug_errno(errno, "Failed to open \"%s\": %m", *dirname); + continue; + } + + return -errno; + } + + FOREACH_DIRENT(de, d, return -errno) { + _cleanup_(unit_file_list_free_onep) UnitFileList *f = NULL; + + if (!unit_name_is_valid(de->d_name, UNIT_NAME_ANY)) + continue; + + if (!strv_fnmatch_or_empty(patterns, de->d_name, FNM_NOESCAPE)) + continue; + + if (hashmap_get(h, de->d_name)) + continue; + + dirent_ensure_type(d, de); + + if (!IN_SET(de->d_type, DT_LNK, DT_REG)) + continue; + + f = new0(UnitFileList, 1); + if (!f) + return -ENOMEM; + + f->path = path_make_absolute(de->d_name, *dirname); + if (!f->path) + return -ENOMEM; + + r = unit_file_lookup_state(scope, &paths, de->d_name, &f->state); + if (r < 0) + f->state = UNIT_FILE_BAD; + + if (!strv_isempty(states) && + !strv_contains(states, unit_file_state_to_string(f->state))) + continue; + + r = hashmap_put(h, basename(f->path), f); + if (r < 0) + return r; + + f = NULL; /* prevent cleanup */ + } + } + + return 0; +} + +static const char* const unit_file_state_table[_UNIT_FILE_STATE_MAX] = { + [UNIT_FILE_ENABLED] = "enabled", + [UNIT_FILE_ENABLED_RUNTIME] = "enabled-runtime", + [UNIT_FILE_LINKED] = "linked", + [UNIT_FILE_LINKED_RUNTIME] = "linked-runtime", + [UNIT_FILE_ALIAS] = "alias", + [UNIT_FILE_MASKED] = "masked", + [UNIT_FILE_MASKED_RUNTIME] = "masked-runtime", + [UNIT_FILE_STATIC] = "static", + [UNIT_FILE_DISABLED] = "disabled", + [UNIT_FILE_INDIRECT] = "indirect", + [UNIT_FILE_GENERATED] = "generated", + [UNIT_FILE_TRANSIENT] = "transient", + [UNIT_FILE_BAD] = "bad", +}; + +DEFINE_STRING_TABLE_LOOKUP(unit_file_state, UnitFileState); + +static const char* const unit_file_change_type_table[_UNIT_FILE_CHANGE_TYPE_MAX] = { + [UNIT_FILE_SYMLINK] = "symlink", + [UNIT_FILE_UNLINK] = "unlink", + [UNIT_FILE_IS_MASKED] = "masked", + [UNIT_FILE_IS_DANGLING] = "dangling", +}; + +DEFINE_STRING_TABLE_LOOKUP(unit_file_change_type, UnitFileChangeType); + +static const char* const unit_file_preset_mode_table[_UNIT_FILE_PRESET_MAX] = { + [UNIT_FILE_PRESET_FULL] = "full", + [UNIT_FILE_PRESET_ENABLE_ONLY] = "enable-only", + [UNIT_FILE_PRESET_DISABLE_ONLY] = "disable-only", +}; + +DEFINE_STRING_TABLE_LOOKUP(unit_file_preset_mode, UnitFilePresetMode); |