shared: extract edit-util from systemctl-edit

src/shared/edit-util.c

@@ -0,0 +1,261 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <stdio.h>
+
+#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 "selinux-util.h"
+#include "stat-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "tmpfile-util.h"
+
+void edit_file_free_all(EditFile **f) {
+        if (!f || !*f)
+                return;
+
+        for (EditFile *i = *f; i->path; i++) {
+                free(i->path);
+                free(i->tmp);
+        }
+
+        free(*f);
+}
+
+int create_edit_temp_file(
+                const char *new_path,
+                const char *original_path,
+                char ** const original_unit_paths,
+                const char *marker_start,
+                const char *marker_end,
+                char **ret_tmp_fn,
+                unsigned *ret_edit_line) {
+
+        _cleanup_free_ char *t = NULL;
+        unsigned ln = 1;
+        int r;
+
+        assert(new_path);
+        assert(ret_tmp_fn);
+        assert(ret_edit_line);
+
+        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;
+
+                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);
+
+                if (fchmod(fileno(f), 0644) < 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"
+                        "%s\n"
+                        "\n"
+                        "%s%s"
+                        "\n"
+                        "%s\n",
+                        new_path,
+                        strempty(marker_start),
+                        strempty(new_contents),
+                        new_contents && endswith(new_contents, "\n") ? "" : "\n",
+                        strempty(marker_end));
+
+                ln = 4; /* start editing at the contents */
+
+                /* 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);
+        *ret_edit_line = ln;
+
+        return 0;
+}
+
+int run_editor(const EditFile *files) {
+        int r;
+
+        assert(files);
+
+        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) {
+                size_t n_editor_args = 0, i = 1, argc;
+                char **editor_args = NULL, **args;
+                const char *editor;
+
+                /* 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))
+                        argc = 1;
+                else {
+                        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;
+                }
+
+                for (const EditFile *f = files; f->path; f++)
+                        argc += 2;
+
+                args = newa(char*, argc + 1);
+
+                if (n_editor_args > 0) {
+                        args[0] = editor_args[0];
+                        for (; i < n_editor_args; i++)
+                                args[i] = editor_args[i];
+                }
+
+                if (files[0].path && files[0].line > 1 && !files[1].path) {
+                        /* If editing a single file only, use the +LINE syntax to put cursor on the right line */
+                        if (asprintf(args + i, "+%u", files[0].line) < 0) {
+                                (void) log_oom();
+                                _exit(EXIT_FAILURE);
+                        }
+
+                        i++;
+                        args[i++] = files[0].tmp;
+                } else
+                        for (const EditFile *f = files; f->path; f++)
+                                args[i++] = f->tmp;
+
+                args[i] = NULL;
+
+                if (n_editor_args > 0)
+                        execvp(args[0], (char* const*) args);
+
+                FOREACH_STRING(name, "editor", "nano", "vim", "vi") {
+                        args[0] = (char*) name;
+                        execvp(name, (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", name);
+                                _exit(EXIT_FAILURE);
+                        }
+                }
+
+                log_error("Cannot edit units, no editor available. Please set either $SYSTEMD_EDITOR, $EDITOR or $VISUAL.");
+                _exit(EXIT_FAILURE);
+        }
+
+        return 0;
+}
+
+int trim_edit_markers(const char *path, const char *marker_start, const char *marker_end) {
+        _cleanup_free_ char *old_contents = NULL, *new_contents = NULL;
+        char *contents_start, *contents_end;
+        const char *c = NULL;
+        int r;
+
+        /* Trim out the lines between the two markers */
+        r = read_full_file(path, &old_contents, NULL);
+        if (r < 0)
+                return log_error_errno(r, "Failed to read temporary file \"%s\": %m", path);
+
+        contents_start = strstr(old_contents, marker_start);
+        if (contents_start)
+                contents_start += strlen(marker_start);
+        else
+                contents_start = old_contents;
+
+        contents_end = strstr(contents_start, marker_end);
+        if (contents_end)
+                contents_end[0] = 0;
+
+        c = strstrip(contents_start);
+        if (isempty(c))
+                return 0; /* All gone now */
+
+        new_contents = strjoin(c, "\n"); /* Trim prefix and suffix, but ensure suffixed by single newline */
+        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; /* Unchanged, but good */
+
+        r = write_string_file(path, 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 modify temporary file \"%s\": %m", path);
+
+        return 1; /* Changed, but good */
+}

src/shared/edit-util.h

@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include "path-lookup.h"
+
+typedef struct EditFile {
+        char *path;
+        char *tmp;
+        unsigned line;
+} EditFile;
+
+void edit_file_free_all(EditFile **ef);
+
+int create_edit_temp_file(
+                const char *new_path,
+                const char *original_path,
+                char ** const original_unit_paths,
+                const char *marker_start,
+                const char *marker_end,
+                char **ret_tmp_fn,
+                unsigned *ret_edit_line);
+
+int run_editor(const EditFile *files);
+
+int trim_edit_markers(const char *path, const char *marker_start, const char *marker_end);

src/shared/meson.build

@@ -54,6 +54,7 @@ shared_sources = files(
         'dm-util.c',
         'dns-domain.c',
         'dropin.c',
+        'edit-util.c',
         'efi-api.c',
         'efi-loader.c',
         'elf-util.c',

src/systemctl/systemctl-edit.c

@@ -1,23 +1,17 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
 #include "bus-error.h"
-#include "copy.h"
-#include "fd-util.h"
-#include "fileio.h"
+#include "edit-util.h"
 #include "fs-util.h"
-#include "mkdir-label.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 contents of the drop-in file"
 #define EDIT_MARKER_END "### Edits below this comment will be discarded"
@@ -110,112 +104,6 @@ int verb_cat(int argc, char *argv[], void *userdata) {
         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,
-                unsigned *ret_edit_line) {
-
-        _cleanup_free_ char *t = NULL;
-        unsigned ln = 1;
-        int r;
-
-        assert(new_path);
-        assert(ret_tmp_fn);
-        assert(ret_edit_line);
-
-        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;
-
-                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);
-
-                if (fchmod(fileno(f), 0644) < 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");
-
-                ln = 4; /* start editing at the contents */
-
-                /* 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);
-        *ret_edit_line = ln;
-
-        return 0;
-}
-
 static int get_file_to_edit(
                 const LookupPaths *paths,
                 const char *name,
@@ -247,24 +135,6 @@ static int get_file_to_edit(
         return 0;
 }
 
-typedef struct EditFile {
-        char *path;
-        char *tmp;
-        unsigned line;
-} EditFile;
-
-static void edit_file_free_all(EditFile **f) {
-        if (!f || !*f)
-                return;
-
-        for (EditFile *i = *f; i->path; i++) {
-                free(i->path);
-                free(i->tmp);
-        }
-
-        free(*f);
-}
-
 static int unit_file_create_new(
                 const LookupPaths *paths,
                 const char *unit_name,
@@ -285,7 +155,7 @@ static int unit_file_create_new(
         if (r < 0)
                 return r;
 
-        r = create_edit_temp_file(new_path, NULL, original_unit_paths, &tmp_path, &edit_line);
+        r = create_edit_temp_file(new_path, NULL, original_unit_paths, EDIT_MARKER_START, EDIT_MARKER_END, &tmp_path, &edit_line);
         if (r < 0)
                 return r;
 
@@ -325,7 +195,7 @@ static int unit_file_create_copy(
                         return log_warning_errno(SYNTHETIC_ERRNO(EKEYREJECTED), "%s skipped.", unit_name);
         }
 
-        r = create_edit_temp_file(new_path, fragment_path, NULL, &tmp_path, &edit_line);
+        r = create_edit_temp_file(new_path, fragment_path, NULL, EDIT_MARKER_START, EDIT_MARKER_END, &tmp_path, &edit_line);
         if (r < 0)
                 return r;
 
@@ -337,87 +207,6 @@ static int unit_file_create_copy(
         return 0;
 }
 
-static int run_editor(const EditFile *files) {
-        int r;
-
-        assert(files);
-
-        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) {
-                size_t n_editor_args = 0, i = 1, argc;
-                char **editor_args = NULL, **args;
-                const char *editor;
-
-                /* 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))
-                        argc = 1;
-                else {
-                        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;
-                }
-
-                for (const EditFile *f = files; f->path; f++)
-                        argc += 2;
-
-                args = newa(char*, argc + 1);
-
-                if (n_editor_args > 0) {
-                        args[0] = editor_args[0];
-                        for (; i < n_editor_args; i++)
-                                args[i] = editor_args[i];
-                }
-
-                if (files[0].path && files[0].line > 1 && !files[1].path) {
-                        /* If editing a single file only, use the +LINE syntax to put cursor on the right line */
-                        if (asprintf(args + i, "+%u", files[0].line) < 0) {
-                                (void) log_oom();
-                                _exit(EXIT_FAILURE);
-                        }
-
-                        i++;
-                        args[i++] = files[0].tmp;
-                } else
-                        for (const EditFile *f = files; f->path; f++)
-                                args[i++] = f->tmp;
-
-                args[i] = NULL;
-
-                if (n_editor_args > 0)
-                        execvp(args[0], (char* const*) args);
-
-                FOREACH_STRING(name, "editor", "nano", "vim", "vi") {
-                        args[0] = (char*) name;
-                        execvp(name, (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", name);
-                                _exit(EXIT_FAILURE);
-                        }
-                }
-
-                log_error("Cannot edit units, 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,
@@ -543,45 +332,6 @@ static int find_paths_to_edit(
         return 0;
 }
 
-static int trim_edit_markers(const char *path) {
-        _cleanup_free_ char *old_contents = NULL, *new_contents = NULL;
-        char *contents_start, *contents_end;
-        const char *c = NULL;
-        int r;
-
-        /* Trim out the lines between the two markers */
-        r = read_full_file(path, &old_contents, NULL);
-        if (r < 0)
-                return log_error_errno(r, "Failed to read temporary file \"%s\": %m", path);
-
-        contents_start = strstr(old_contents, EDIT_MARKER_START);
-        if (contents_start)
-                contents_start += strlen(EDIT_MARKER_START);
-        else
-                contents_start = old_contents;
-
-        contents_end = strstr(contents_start, EDIT_MARKER_END);
-        if (contents_end)
-                contents_end[0] = 0;
-
-        c = strstrip(contents_start);
-        if (isempty(c))
-                return 0; /* All gone now */
-
-        new_contents = strjoin(c, "\n"); /* Trim prefix and suffix, but ensure suffixed by single newline */
-        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; /* Unchanged, but good */
-
-        r = write_string_file(path, 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 modify temporary file \"%s\": %m", path);
-
-        return 1; /* Changed, but good */
-}
-
 int verb_edit(int argc, char *argv[], void *userdata) {
         _cleanup_(edit_file_free_all) EditFile *edit_files = NULL;
         _cleanup_(lookup_paths_free) LookupPaths lp = {};
@@ -634,7 +384,7 @@ int verb_edit(int argc, char *argv[], void *userdata) {
         for (EditFile *f = edit_files; f->path; f++) {
                 /* If the temporary file is empty we ignore it. This allows the user to cancel the
                  * modification. */
-                r = trim_edit_markers(f->tmp);
+                r = trim_edit_markers(f->tmp, EDIT_MARKER_START, EDIT_MARKER_END);
                 if (r < 0)
                         goto end;
                 if (r == 0) /* has no actual contents? then ignore it */