/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include #include #include "alloc-util.h" #include "copy.h" #include "edit-util.h" #include "fd-util.h" #include "fileio.h" #include "fs-util.h" #include "mkdir-label.h" #include "path-util.h" #include "process-util.h" #include "string-util.h" #include "strv.h" #include "tmpfile-util-label.h" void edit_file_context_done(EditFileContext *context) { int r; assert(context); FOREACH_ARRAY(i, context->files, context->n_files) { unlink_and_free(i->temp); if (context->remove_parent) { _cleanup_free_ char *parent = NULL; r = path_extract_directory(i->path, &parent); if (r < 0) log_debug_errno(r, "Failed to extract directory from '%s', ignoring: %m", i->path); else if (rmdir(parent) < 0 && !IN_SET(errno, ENOENT, ENOTEMPTY)) log_debug_errno(errno, "Failed to remove parent directory '%s', ignoring: %m", parent); } free(i->path); free(i->original_path); strv_free(i->comment_paths); } context->files = mfree(context->files); context->n_files = 0; } bool edit_files_contains(const EditFileContext *context, const char *path) { assert(context); assert(path); FOREACH_ARRAY(i, context->files, context->n_files) if (path_equal(i->path, path)) return true; return false; } int edit_files_add( EditFileContext *context, const char *path, const char *original_path, char * const *comment_paths) { _cleanup_free_ char *new_path = NULL, *new_original_path = NULL; _cleanup_strv_free_ char **new_comment_paths = NULL; assert(context); assert(path); if (edit_files_contains(context, path)) return 0; if (!GREEDY_REALLOC(context->files, context->n_files + 1)) return log_oom(); new_path = strdup(path); if (!new_path) return log_oom(); if (original_path) { new_original_path = strdup(original_path); if (!new_original_path) return log_oom(); } if (comment_paths) { new_comment_paths = strv_copy(comment_paths); if (!new_comment_paths) return log_oom(); } context->files[context->n_files] = (EditFile) { .context = context, .path = TAKE_PTR(new_path), .original_path = TAKE_PTR(new_original_path), .comment_paths = TAKE_PTR(new_comment_paths), }; context->n_files++; return 1; } static int create_edit_temp_file(EditFile *e) { _cleanup_(unlink_and_freep) char *temp = NULL; _cleanup_fclose_ FILE *f = NULL; const char *source; bool has_original, has_target; unsigned line = 1; int r; assert(e); assert(e->context); assert(e->path); assert(!e->comment_paths || (e->context->marker_start && e->context->marker_end)); if (e->temp) return 0; r = mkdir_parents_label(e->path, 0755); if (r < 0) return log_error_errno(r, "Failed to create parent directories for '%s': %m", e->path); r = fopen_temporary_label(e->path, e->path, &f, &temp); if (r < 0) return log_error_errno(r, "Failed to create temporary file for '%s': %m", e->path); if (fchmod(fileno(f), 0644) < 0) return log_error_errno(errno, "Failed to change mode of temporary file '%s': %m", temp); has_original = e->original_path && access(e->original_path, F_OK) >= 0; has_target = access(e->path, F_OK) >= 0; if (has_original && (!has_target || e->context->overwrite_with_origin)) /* We are asked to overwrite target with original_path or target doesn't exist. */ source = e->original_path; else if (has_target) /* Target exists and shouldn't be overwritten. */ source = e->path; else source = NULL; if (e->comment_paths) { _cleanup_free_ char *source_contents = NULL; if (source) { r = read_full_file(source, &source_contents, NULL); if (r < 0) return log_error_errno(r, "Failed to read source file '%s': %m", source); } fprintf(f, "### Editing %s\n" "%s\n" "\n" "%s%s" "\n" "%s\n", e->path, e->context->marker_start, strempty(source_contents), source_contents && endswith(source_contents, "\n") ? "" : "\n", e->context->marker_end); line = 4; /* Start editing at the contents area */ STRV_FOREACH(path, e->comment_paths) { _cleanup_free_ char *comment = NULL; /* Skip the file which is being edited and the source file (can be the same) */ if (PATH_IN_SET(*path, e->path, source)) continue; r = read_full_file(*path, &comment, NULL); if (r < 0) return log_error_errno(r, "Failed to read comment file '%s': %m", *path); fprintf(f, "\n\n### %s", *path); if (!isempty(comment)) { _cleanup_free_ char *c = NULL; c = strreplace(strstrip(comment), "\n", "\n# "); if (!c) return log_oom(); fprintf(f, "\n# %s", c); } } } else if (source) { r = copy_file_fd(source, fileno(f), COPY_REFLINK); if (r < 0) { assert(r != -ENOENT); return log_error_errno(r, "Failed to copy file '%s' to temporary file '%s': %m", source, temp); } } r = fflush_and_check(f); if (r < 0) return log_error_errno(r, "Failed to write to temporary file '%s': %m", temp); e->temp = TAKE_PTR(temp); e->line = line; return 0; } static int run_editor_child(const EditFileContext *context) { _cleanup_strv_free_ char **args = NULL; const char *editor; int r; /* 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)) { _cleanup_strv_free_ char **editor_args = NULL; editor_args = strv_split(editor, WHITESPACE); if (!editor_args) return log_oom(); args = TAKE_PTR(editor_args); } if (context->n_files == 1 && context->files[0].line > 1) { /* If editing a single file only, use the +LINE syntax to put cursor on the right line */ r = strv_extendf(&args, "+%u", context->files[0].line); if (r < 0) return log_oom(); } FOREACH_ARRAY(i, context->files, context->n_files) { r = strv_extend(&args, i->temp); if (r < 0) return log_oom(); } if (!isempty(editor)) execvp(args[0], (char* const*) args); bool prepended = false; FOREACH_STRING(name, "editor", "nano", "vim", "vi") { if (!prepended) { r = strv_prepend(&args, name); prepended = true; } else r = free_and_strdup(&args[0], name); if (r < 0) return log_oom(); execvp(args[0], (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) return log_error_errno(errno, "Failed to execute '%s': %m", name); } return log_error_errno(SYNTHETIC_ERRNO(ENOENT), "Cannot edit files, no editor available. Please set either $SYSTEMD_EDITOR, $EDITOR or $VISUAL."); } static int run_editor(const EditFileContext *context) { int r; assert(context); r = safe_fork("(editor)", FORK_RESET_SIGNALS|FORK_DEATHSIG_SIGTERM|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG|FORK_WAIT, NULL); if (r < 0) return r; if (r == 0) { /* Child */ r = run_editor_child(context); _exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS); } return 0; } static int strip_edit_temp_file(EditFile *e) { _cleanup_free_ char *old_contents = NULL, *new_contents = NULL; const char *stripped; int r; assert(e); assert(e->context); assert(e->temp); r = read_full_file(e->temp, &old_contents, NULL); if (r < 0) return log_error_errno(r, "Failed to read temporary file '%s': %m", e->temp); if (e->context->marker_start) { /* Trim out the lines between the two markers */ char *contents_start, *contents_end; assert(e->context->marker_end); contents_start = strstrafter(old_contents, e->context->marker_start); if (!contents_start) contents_start = old_contents; contents_end = strstr(contents_start, e->context->marker_end); if (contents_end) *contents_end = '\0'; stripped = strstrip(contents_start); } else stripped = strstrip(old_contents); if (isempty(stripped)) return 0; /* File is empty (has no real changes) */ /* Trim prefix and suffix, but ensure suffixed by single newline */ new_contents = strjoin(stripped, "\n"); if (!new_contents) return log_oom(); if (streq(old_contents, new_contents)) /* Don't touch the file if the above didn't change a thing */ return 1; /* Contents unchanged after stripping but has changes */ r = write_string_file(e->temp, new_contents, WRITE_STRING_FILE_CREATE | WRITE_STRING_FILE_TRUNCATE | WRITE_STRING_FILE_AVOID_NEWLINE); if (r < 0) return log_error_errno(r, "Failed to strip temporary file '%s': %m", e->temp); return 1; /* Contents have real changes and are changed after stripping */ } int do_edit_files_and_install(EditFileContext *context) { int r; assert(context); if (context->n_files == 0) return log_debug_errno(SYNTHETIC_ERRNO(ENOENT), "Got no files to edit."); FOREACH_ARRAY(i, context->files, context->n_files) { r = create_edit_temp_file(i); if (r < 0) return r; } r = run_editor(context); if (r < 0) return r; FOREACH_ARRAY(i, context->files, context->n_files) { /* Always call strip_edit_temp_file which will tell if the temp file has actual changes */ r = strip_edit_temp_file(i); if (r < 0) return r; if (r == 0) /* temp file doesn't carry actual changes, ignoring */ continue; r = RET_NERRNO(rename(i->temp, i->path)); if (r < 0) return log_error_errno(r, "Failed to rename temporary file '%s' to target file '%s': %m", i->temp, i->path); i->temp = mfree(i->temp); log_info("Successfully installed edited file '%s'.", i->path); } return 0; }