Adding upstream version 1.21.22.upstream/1.21.22upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 884 insertions, 0 deletions

diff --git a/src/divert/main.c b/src/divert/main.c
new file mode 100644
index 0000000..865796d
--- /dev/null
+++ b/src/divert/main.c
@@ -0,0 +1,884 @@
+/*
+ * dpkg-divert - override a package's version of a file
+ *
+ * Copyright © 1995 Ian Jackson
+ * Copyright © 2000, 2001 Wichert Akkerman
+ * Copyright © 2006-2015, 2017-2018 Guillem Jover <guillem@debian.org>
+ * Copyright © 2011 Linaro Limited
+ * Copyright © 2011 Raphaël Hertzog <hertzog@debian.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <compat.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <errno.h>
+#if HAVE_LOCALE_H
+#include <locale.h>
+#endif
+#include <fcntl.h>
+#include <fnmatch.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <dpkg/i18n.h>
+#include <dpkg/dpkg.h>
+#include <dpkg/dpkg-db.h>
+#include <dpkg/debug.h>
+#include <dpkg/arch.h>
+#include <dpkg/file.h>
+#include <dpkg/glob.h>
+#include <dpkg/buffer.h>
+#include <dpkg/options.h>
+#include <dpkg/db-fsys.h>
+
+
+static const char printforhelp[] = N_(
+"Use --help for help about diverting files.");
+
+static bool opt_pkgname_match_any = true;
+static const char *opt_pkgname = NULL;
+static const char *opt_divertto = NULL;
+
+static int opt_verbose = 1;
+static int opt_test = 0;
+static int opt_rename = -1;
+
+
+static int
+printversion(const char *const *argv)
+{
+	printf(_("Debian %s version %s.\n"), dpkg_get_progname(),
+	       PACKAGE_RELEASE);
+
+	printf(_(
+"This is free software; see the GNU General Public License version 2 or\n"
+"later for copying conditions. There is NO warranty.\n"));
+
+	m_output(stdout, _("<standard output>"));
+
+	return 0;
+}
+
+static int
+usage(const char *const *argv)
+{
+	printf(_(
+"Usage: %s [<option>...] <command>\n"
+"\n"), dpkg_get_progname());
+
+	printf(_(
+"Commands:\n"
+"  [--add] <file>           add a diversion.\n"
+"  --remove <file>          remove the diversion.\n"
+"  --list [<glob-pattern>]  show file diversions.\n"
+"  --listpackage <file>     show what package diverts the file.\n"
+"  --truename <file>        return the diverted file.\n"
+"\n"));
+
+	printf(_(
+"Options:\n"
+"  --package <package>      name of the package whose copy of <file> will not\n"
+"                             be diverted.\n"
+"  --local                  all packages' versions are diverted.\n"
+"  --divert <divert-to>     the name used by other packages' versions.\n"
+"  --rename                 actually move the file aside (or back).\n"
+"  --no-rename              do not move the file aside (or back) (default).\n"
+"  --admindir <directory>   set the directory with the diversions file.\n"
+"  --instdir <directory>    set the root directory, but not the admin dir.\n"
+"  --root <directory>       set the directory of the root filesystem.\n"
+"  --test                   don't do anything, just demonstrate.\n"
+"  --quiet                  quiet operation, minimal output.\n"
+"  --help                   show this help message.\n"
+"  --version                show the version.\n"
+"\n"));
+
+	printf(_(
+"When adding, default is --local and --divert <original>.distrib.\n"
+"When removing, --package or --local and --divert must match if specified.\n"
+"Package preinst/postrm scripts should always specify --package and --divert.\n"));
+
+	m_output(stdout, _("<standard output>"));
+
+	return 0;
+}
+
+static void
+opt_rename_setup(void)
+{
+	if (opt_rename >= 0)
+		return;
+
+	opt_rename = 0;
+	warning(_("please specify --no-rename explicitly, the default "
+	          "will change to --rename in 1.20.x"));
+}
+
+struct file {
+	char *name;
+	enum {
+		FILE_STAT_INVALID,
+		FILE_STAT_VALID,
+		FILE_STAT_NOFILE,
+	} stat_state;
+	struct stat stat;
+};
+
+static void
+file_init(struct file *f, const char *filename)
+{
+	struct varbuf usefilename = VARBUF_INIT;
+
+	varbuf_add_str(&usefilename, dpkg_fsys_get_dir());
+	varbuf_add_str(&usefilename, filename);
+	varbuf_end_str(&usefilename);
+
+	f->name = varbuf_detach(&usefilename);
+	f->stat_state = FILE_STAT_INVALID;
+}
+
+static void
+file_destroy(struct file *f)
+{
+	free(f->name);
+}
+
+static void
+file_stat(struct file *f)
+{
+	int ret;
+
+	if (f->stat_state != FILE_STAT_INVALID)
+		return;
+
+	ret = lstat(f->name, &f->stat);
+	if (ret && errno != ENOENT)
+		ohshite(_("cannot stat file '%s'"), f->name);
+
+	if (ret == 0)
+		f->stat_state = FILE_STAT_VALID;
+	else
+		f->stat_state = FILE_STAT_NOFILE;
+}
+
+static void
+check_writable_dir(struct file *f)
+{
+	char *tmpname;
+	int tmpfd;
+
+	tmpname = str_fmt("%s%s", f->name, ".dpkg-divert.tmp");
+
+	tmpfd = creat(tmpname, 0600);
+	if (tmpfd < 0)
+		ohshite(_("error checking '%s'"), f->name);
+	close(tmpfd);
+	(void)unlink(tmpname);
+
+	free(tmpname);
+}
+
+static bool
+check_rename(struct file *src, struct file *dst)
+{
+	file_stat(src);
+
+	/* If the source file is not present and we are not going to do
+	 * the rename anyway there's no point in checking any further. */
+	if (src->stat_state == FILE_STAT_NOFILE)
+		return false;
+
+	file_stat(dst);
+
+	/*
+	 * Unfortunately we have to check for write access in both places,
+	 * just having +w is not enough, since people do mount things RO,
+	 * and we need to fail before we start mucking around with things.
+	 * So we open a file with the same name as the diversions but with
+	 * an extension that (hopefully) won't overwrite anything. If it
+	 * succeeds, we assume a writable filesystem.
+	 */
+
+	check_writable_dir(src);
+	check_writable_dir(dst);
+
+	if (src->stat_state == FILE_STAT_VALID &&
+	    dst->stat_state == FILE_STAT_VALID &&
+	    !(src->stat.st_dev == dst->stat.st_dev &&
+	      src->stat.st_ino == dst->stat.st_ino))
+		ohshit(_("rename involves overwriting '%s' with\n"
+		         "  different file '%s', not allowed"),
+		        dst->name, src->name);
+
+	return true;
+}
+
+static void
+file_copy(const char *src, const char *dst)
+{
+	struct dpkg_error err;
+	char *tmp;
+	int srcfd, dstfd;
+
+	srcfd = open(src, O_RDONLY);
+	if (srcfd < 0)
+		ohshite(_("unable to open file '%s'"), src);
+
+	tmp = str_fmt("%s%s", dst, ".dpkg-divert.tmp");
+	dstfd = creat(tmp, 0600);
+	if (dstfd < 0)
+		ohshite(_("unable to create file '%s'"), tmp);
+
+	push_cleanup(cu_filename, ~ehflag_normaltidy, 1, tmp);
+
+	if (fd_fd_copy(srcfd, dstfd, -1, &err) < 0)
+		ohshit(_("cannot copy '%s' to '%s': %s"), src, tmp, err.str);
+
+	close(srcfd);
+
+	if (fsync(dstfd))
+		ohshite(_("unable to sync file '%s'"), tmp);
+	if (close(dstfd))
+		ohshite(_("unable to close file '%s'"), tmp);
+
+	file_copy_perms(src, tmp);
+
+	if (rename(tmp, dst) != 0)
+		ohshite(_("cannot rename '%s' to '%s'"), tmp, dst);
+
+	free(tmp);
+
+	pop_cleanup(ehflag_normaltidy);
+}
+
+static void
+file_rename(struct file *src, struct file *dst)
+{
+	if (src->stat_state == FILE_STAT_NOFILE)
+		return;
+
+	if (dst->stat_state == FILE_STAT_VALID) {
+		if (unlink(src->name))
+			ohshite(_("rename: remove duplicate old link '%s'"),
+			        src->name);
+	} else {
+		if (rename(src->name, dst->name) == 0)
+			return;
+
+		/* If a rename didn't work try moving the file instead. */
+		file_copy(src->name, dst->name);
+
+		if (unlink(src->name))
+			ohshite(_("unable to remove copied source file '%s'"),
+			        src->name);
+	}
+}
+
+static void
+diversion_check_filename(const char *filename)
+{
+	if (filename[0] != '/')
+		badusage(_("filename \"%s\" is not absolute"), filename);
+	if (strchr(filename, '\n') != NULL)
+		badusage(_("file may not contain newlines"));
+}
+
+static const char *
+diversion_pkg_name(struct fsys_diversion *d)
+{
+	if (d->pkgset == NULL)
+		return ":";
+	else
+		return d->pkgset->name;
+}
+
+static const char *
+varbuf_diversion(struct varbuf *str, const char *pkgname,
+                 const char *filename, const char *divertto)
+{
+	varbuf_reset(str);
+
+	if (pkgname == NULL) {
+		if (divertto == NULL)
+			varbuf_printf(str, _("local diversion of %s"), filename);
+		else
+			varbuf_printf(str, _("local diversion of %s to %s"),
+			              filename, divertto);
+	} else {
+		if (divertto == NULL)
+			varbuf_printf(str, _("diversion of %s by %s"),
+			              filename, pkgname);
+		else
+			varbuf_printf(str, _("diversion of %s to %s by %s"),
+			              filename, divertto, pkgname);
+	}
+
+	return str->buf;
+}
+
+static const char *
+diversion_current(const char *filename)
+{
+	static struct varbuf str = VARBUF_INIT;
+
+	if (opt_pkgname_match_any) {
+		varbuf_reset(&str);
+
+		if (opt_divertto == NULL)
+			varbuf_printf(&str, _("any diversion of %s"), filename);
+		else
+			varbuf_printf(&str, _("any diversion of %s to %s"),
+			              filename, opt_divertto);
+	} else {
+		return varbuf_diversion(&str, opt_pkgname, filename, opt_divertto);
+	}
+
+	return str.buf;
+}
+
+static const char *
+diversion_describe(struct fsys_diversion *d)
+{
+	static struct varbuf str = VARBUF_INIT;
+	const char *pkgname;
+	const char *name_from, *name_to;
+
+	if (d->camefrom) {
+		name_from = d->camefrom->name;
+		name_to = d->camefrom->divert->useinstead->name;
+	} else {
+		name_from = d->useinstead->divert->camefrom->name;
+		name_to = d->useinstead->name;
+	}
+
+	if (d->pkgset == NULL)
+		pkgname = NULL;
+	else
+		pkgname = d->pkgset->name;
+
+	return varbuf_diversion(&str, pkgname, name_from, name_to);
+}
+
+static void
+divertdb_write(void)
+{
+	char *dbname;
+	struct atomic_file *file;
+	struct fsys_hash_iter *iter;
+	struct fsys_namenode *namenode;
+
+	dbname = dpkg_db_get_path(DIVERSIONSFILE);
+
+	file = atomic_file_new(dbname, ATOMIC_FILE_BACKUP);
+	atomic_file_open(file);
+
+	iter = fsys_hash_iter_new();
+	while ((namenode = fsys_hash_iter_next(iter))) {
+		struct fsys_diversion *d = namenode->divert;
+
+		if (d == NULL || d->useinstead == NULL)
+			continue;
+
+		fprintf(file->fp, "%s\n%s\n%s\n",
+		        d->useinstead->divert->camefrom->name,
+		        d->useinstead->name,
+		        diversion_pkg_name(d));
+	}
+	fsys_hash_iter_free(iter);
+
+	atomic_file_sync(file);
+	atomic_file_close(file);
+	atomic_file_commit(file);
+	atomic_file_free(file);
+
+	free(dbname);
+}
+
+static bool
+diversion_is_essential(struct fsys_namenode *namenode)
+{
+	struct pkginfo *pkg;
+	struct pkg_hash_iter *pkg_iter;
+	struct fsys_node_pkgs_iter *iter;
+	bool essential = false;
+
+	pkg_iter = pkg_hash_iter_new();
+	while ((pkg = pkg_hash_iter_next_pkg(pkg_iter))) {
+		if (pkg->installed.essential)
+			ensure_packagefiles_available(pkg);
+	}
+	pkg_hash_iter_free(pkg_iter);
+
+	iter = fsys_node_pkgs_iter_new(namenode);
+	while ((pkg = fsys_node_pkgs_iter_next(iter))) {
+		if (pkg->installed.essential) {
+			essential = true;
+			break;
+		}
+	}
+	fsys_node_pkgs_iter_free(iter);
+
+	return essential;
+}
+
+static bool
+diversion_is_owned_by_self(struct pkgset *set, struct fsys_namenode *namenode)
+{
+	struct pkginfo *pkg;
+	struct fsys_node_pkgs_iter *iter;
+	bool owned = false;
+
+	if (set == NULL)
+		return false;
+
+	for (pkg = &set->pkg; pkg; pkg = pkg->arch_next)
+		ensure_packagefiles_available(pkg);
+
+	iter = fsys_node_pkgs_iter_new(namenode);
+	while ((pkg = fsys_node_pkgs_iter_next(iter))) {
+		if (pkg->set == set) {
+			owned = true;
+			break;
+		}
+	}
+	fsys_node_pkgs_iter_free(iter);
+
+	return owned;
+}
+
+static int
+diversion_add(const char *const *argv)
+{
+	const char *filename = argv[0];
+	struct file file_from, file_to;
+	struct fsys_diversion *contest, *altname;
+	struct fsys_namenode *fnn_from, *fnn_to;
+	struct pkgset *pkgset;
+
+	opt_pkgname_match_any = false;
+	opt_rename_setup();
+
+	/* Handle filename. */
+	if (!filename || argv[1])
+		badusage(_("--%s needs a single argument"), cipaction->olong);
+
+	diversion_check_filename(filename);
+
+	modstatdb_open(msdbrw_readonly);
+	ensure_diversions();
+
+	file_init(&file_from, filename);
+	file_stat(&file_from);
+
+	if (file_from.stat_state == FILE_STAT_VALID &&
+	    S_ISDIR(file_from.stat.st_mode))
+		badusage(_("cannot divert directories"));
+
+	fnn_from = fsys_hash_find_node(filename, 0);
+
+	/* Handle divertto. */
+	if (opt_divertto == NULL)
+		opt_divertto = str_fmt("%s.distrib", filename);
+
+	if (strcmp(filename, opt_divertto) == 0)
+		badusage(_("cannot divert file '%s' to itself"), filename);
+
+	file_init(&file_to, opt_divertto);
+
+	fnn_to = fsys_hash_find_node(opt_divertto, 0);
+
+	/* Handle package name. */
+	if (opt_pkgname == NULL)
+		pkgset = NULL;
+	else
+		pkgset = pkg_hash_find_set(opt_pkgname);
+
+	/* Check we are not stomping over an existing diversion. */
+	if (fnn_from->divert || fnn_to->divert) {
+		if (fnn_to->divert && fnn_to->divert->camefrom &&
+		    strcmp(fnn_to->divert->camefrom->name, filename) == 0 &&
+		    fnn_from->divert && fnn_from->divert->useinstead &&
+		    strcmp(fnn_from->divert->useinstead->name, opt_divertto) == 0 &&
+		    fnn_from->divert->pkgset == pkgset) {
+			if (opt_verbose > 0)
+				printf(_("Leaving '%s'\n"),
+				       diversion_describe(fnn_from->divert));
+
+			file_destroy(&file_from);
+			file_destroy(&file_to);
+
+			modstatdb_shutdown();
+
+			return 0;
+		}
+
+		ohshit(_("'%s' clashes with '%s'"),
+		       diversion_current(filename),
+		       fnn_from->divert ?
+		       diversion_describe(fnn_from->divert) :
+		       diversion_describe(fnn_to->divert));
+	}
+
+	/* Create new diversion. */
+	contest = nfmalloc(sizeof(*contest));
+	altname = nfmalloc(sizeof(*altname));
+
+	altname->camefrom = fnn_from;
+	altname->camefrom->divert = contest;
+	altname->useinstead = NULL;
+	altname->pkgset = pkgset;
+
+	contest->useinstead = fnn_to;
+	contest->useinstead->divert = altname;
+	contest->camefrom = NULL;
+	contest->pkgset = pkgset;
+
+	/* Update database and file system if needed. */
+	if (opt_verbose > 0)
+		printf(_("Adding '%s'\n"), diversion_describe(contest));
+	if (opt_rename)
+		opt_rename = check_rename(&file_from, &file_to);
+	/* Check we are not renaming a file owned by the diverting pkgset. */
+	if (opt_rename && diversion_is_owned_by_self(pkgset, fnn_from)) {
+		if (opt_verbose > 0)
+			printf(_("Ignoring request to rename file '%s' "
+			         "owned by diverting package '%s'\n"),
+			       filename, pkgset->name);
+		opt_rename = false;
+	}
+	if (opt_rename && diversion_is_essential(fnn_from))
+		warning(_("diverting file '%s' from an Essential package with "
+		          "rename is dangerous, use --no-rename"), filename);
+	if (!opt_test) {
+		divertdb_write();
+		if (opt_rename)
+			file_rename(&file_from, &file_to);
+	}
+
+	file_destroy(&file_from);
+	file_destroy(&file_to);
+
+	modstatdb_shutdown();
+
+	return 0;
+}
+
+static bool
+diversion_is_shared(struct pkgset *set, struct fsys_namenode *namenode)
+{
+	const char *archname;
+	struct pkginfo *pkg;
+	struct dpkg_arch *arch;
+	struct fsys_node_pkgs_iter *iter;
+	bool shared = false;
+
+	if (set == NULL)
+		return false;
+
+	archname = getenv("DPKG_MAINTSCRIPT_ARCH");
+	arch = dpkg_arch_find(archname);
+	if (arch->type == DPKG_ARCH_NONE || arch->type == DPKG_ARCH_EMPTY)
+		return false;
+
+	for (pkg = &set->pkg; pkg; pkg = pkg->arch_next)
+		ensure_packagefiles_available(pkg);
+
+	iter = fsys_node_pkgs_iter_new(namenode);
+	while ((pkg = fsys_node_pkgs_iter_next(iter))) {
+		if (pkg->set == set && pkg->installed.arch != arch) {
+			shared = true;
+			break;
+		}
+	}
+	fsys_node_pkgs_iter_free(iter);
+
+	return shared;
+}
+
+static int
+diversion_remove(const char *const *argv)
+{
+	const char *filename = argv[0];
+	struct fsys_namenode *namenode;
+	struct fsys_diversion *contest, *altname;
+	struct file file_from, file_to;
+	struct pkgset *pkgset;
+
+	opt_rename_setup();
+
+	if (!filename || argv[1])
+		badusage(_("--%s needs a single argument"), cipaction->olong);
+
+	diversion_check_filename(filename);
+
+	modstatdb_open(msdbrw_readonly);
+	ensure_diversions();
+
+	namenode = fsys_hash_find_node(filename, FHFF_NONE);
+
+	if (namenode == NULL || namenode->divert == NULL ||
+	    namenode->divert->useinstead == NULL) {
+		if (opt_verbose > 0)
+			printf(_("No diversion '%s', none removed.\n"),
+			       diversion_current(filename));
+		modstatdb_shutdown();
+		return 0;
+	}
+
+	if (opt_pkgname == NULL)
+		pkgset = NULL;
+	else
+		pkgset = pkg_hash_find_set(opt_pkgname);
+
+	contest = namenode->divert;
+	altname = contest->useinstead->divert;
+
+	if (opt_divertto != NULL &&
+	    strcmp(opt_divertto, contest->useinstead->name) != 0)
+		ohshit(_("mismatch on divert-to\n"
+		         "  when removing '%s'\n"
+		         "  found '%s'"),
+		       diversion_current(filename),
+		       diversion_describe(contest));
+
+	if (!opt_pkgname_match_any && pkgset != contest->pkgset)
+		ohshit(_("mismatch on package\n"
+		         "  when removing '%s'\n"
+		         "  found '%s'"),
+		       diversion_current(filename),
+		       diversion_describe(contest));
+
+	/* Ignore removal request if the diverted file is still owned
+	 * by another package in the same set. */
+	if (diversion_is_shared(pkgset, namenode)) {
+		if (opt_verbose > 0)
+			printf(_("Ignoring request to remove shared diversion '%s'.\n"),
+			       diversion_describe(contest));
+		modstatdb_shutdown();
+		return 0;
+	}
+
+	if (opt_verbose > 0)
+		printf(_("Removing '%s'\n"), diversion_describe(contest));
+
+	file_init(&file_from, altname->camefrom->name);
+	file_init(&file_to, contest->useinstead->name);
+
+	/* Remove entries from database. */
+	contest->useinstead->divert = NULL;
+	altname->camefrom->divert = NULL;
+
+	if (opt_rename)
+		opt_rename = check_rename(&file_to, &file_from);
+	if (opt_rename && !opt_test)
+		file_rename(&file_to, &file_from);
+
+	if (!opt_test)
+		divertdb_write();
+
+	file_destroy(&file_from);
+	file_destroy(&file_to);
+
+	modstatdb_shutdown();
+
+	return 0;
+}
+
+static int
+diversion_list(const char *const *argv)
+{
+	struct fsys_hash_iter *iter;
+	struct fsys_namenode *namenode;
+	struct glob_node *glob_list = NULL;
+	const char *pattern;
+
+	modstatdb_open(msdbrw_readonly);
+	ensure_diversions();
+
+	while ((pattern = *argv++))
+		glob_list_prepend(&glob_list, m_strdup(pattern));
+
+	if (glob_list == NULL)
+		glob_list_prepend(&glob_list, m_strdup("*"));
+
+	iter = fsys_hash_iter_new();
+	while ((namenode = fsys_hash_iter_next(iter))) {
+		struct glob_node *g;
+		struct fsys_diversion *contest = namenode->divert;
+		struct fsys_diversion *altname;
+		const char *pkgname;
+
+		if (contest == NULL || contest->useinstead == NULL)
+			continue;
+
+		altname = contest->useinstead->divert;
+
+		pkgname = diversion_pkg_name(contest);
+
+		for (g = glob_list; g; g = g->next) {
+			if (fnmatch(g->pattern, pkgname, 0) == 0 ||
+			    fnmatch(g->pattern, contest->useinstead->name, 0) == 0 ||
+			    fnmatch(g->pattern, altname->camefrom->name, 0) == 0) {
+				printf("%s\n", diversion_describe(contest));
+				break;
+			}
+		}
+	}
+	fsys_hash_iter_free(iter);
+
+	glob_list_free(glob_list);
+
+	modstatdb_shutdown();
+
+	return 0;
+}
+
+static int
+diversion_truename(const char *const *argv)
+{
+	const char *filename = argv[0];
+	struct fsys_namenode *namenode;
+
+	if (!filename || argv[1])
+		badusage(_("--%s needs a single argument"), cipaction->olong);
+
+	diversion_check_filename(filename);
+
+	modstatdb_open(msdbrw_readonly);
+	ensure_diversions();
+
+	namenode = fsys_hash_find_node(filename, FHFF_NONE);
+
+	/* Print the given name if file is not diverted. */
+	if (namenode && namenode->divert && namenode->divert->useinstead)
+		printf("%s\n", namenode->divert->useinstead->name);
+	else
+		printf("%s\n", filename);
+
+	modstatdb_shutdown();
+
+	return 0;
+}
+
+static int
+diversion_listpackage(const char *const *argv)
+{
+	const char *filename = argv[0];
+	struct fsys_namenode *namenode;
+
+	if (!filename || argv[1])
+		badusage(_("--%s needs a single argument"), cipaction->olong);
+
+	diversion_check_filename(filename);
+
+	modstatdb_open(msdbrw_readonly);
+	ensure_diversions();
+
+	namenode = fsys_hash_find_node(filename, FHFF_NONE);
+
+	/* Print nothing if file is not diverted. */
+	if (namenode == NULL || namenode->divert == NULL)
+		return 0;
+
+	if (namenode->divert->pkgset == NULL)
+		/* Indicate package is local using something not in package
+		 * namespace. */
+		printf("LOCAL\n");
+	else
+		printf("%s\n", namenode->divert->pkgset->name);
+
+	modstatdb_shutdown();
+
+	return 0;
+}
+
+static void
+set_package(const struct cmdinfo *cip, const char *value)
+{
+	opt_pkgname_match_any = false;
+
+	/* If value is NULL we are being called from --local. */
+	opt_pkgname = value;
+
+	if (opt_pkgname && strchr(opt_pkgname, '\n') != NULL)
+		badusage(_("package may not contain newlines"));
+}
+
+static void
+set_divertto(const struct cmdinfo *cip, const char *value)
+{
+	opt_divertto = value;
+
+	if (opt_divertto[0] != '/')
+		badusage(_("filename \"%s\" is not absolute"), opt_divertto);
+	if (strchr(opt_divertto, '\n') != NULL)
+		badusage(_("divert-to may not contain newlines"));
+}
+
+static const struct cmdinfo cmdinfo_add =
+	ACTION("add",         0, 0, diversion_add);
+
+static const struct cmdinfo cmdinfos[] = {
+	ACTION("add",         0, 0, diversion_add),
+	ACTION("remove",      0, 0, diversion_remove),
+	ACTION("list",        0, 0, diversion_list),
+	ACTION("listpackage", 0, 0, diversion_listpackage),
+	ACTION("truename",    0, 0, diversion_truename),
+	ACTION("help",        '?', 0, usage),
+	ACTION("version",     0,   0, printversion),
+
+	{ "admindir",   0,   1,  NULL,         NULL,      set_admindir, 0 },
+	{ "instdir",    0,   1,  NULL,         NULL,      set_instdir,  0 },
+	{ "root",       0,   1,  NULL,         NULL,      set_root,     0 },
+	{ "divert",     0,   1,  NULL,         NULL,      set_divertto  },
+	{ "package",    0,   1,  NULL,         NULL,      set_package   },
+	{ "local",      0,   0,  NULL,         NULL,      set_package   },
+	{ "quiet",      0,   0,  &opt_verbose, NULL,      NULL, 0       },
+	{ "rename",     0,   0,  &opt_rename,  NULL,      NULL, 1       },
+	{ "no-rename",  0,   0,  &opt_rename,  NULL,      NULL, 0       },
+	{ "test",       0,   0,  &opt_test,    NULL,      NULL, 1       },
+	{  NULL,        0                                               }
+};
+
+int
+main(int argc, const char * const *argv)
+{
+	const char *env_pkgname;
+	int ret;
+
+	dpkg_locales_init(PACKAGE);
+	dpkg_program_init("dpkg-divert");
+	dpkg_options_parse(&argv, cmdinfos, printforhelp);
+
+	debug(dbg_general, "root=%s admindir=%s", dpkg_fsys_get_dir(), dpkg_db_get_dir());
+
+	env_pkgname = getenv("DPKG_MAINTSCRIPT_PACKAGE");
+	if (opt_pkgname_match_any && env_pkgname)
+		set_package(NULL, env_pkgname);
+
+	if (!cipaction)
+		setaction(&cmdinfo_add, NULL);
+
+	ret = cipaction->action(argv);
+
+	dpkg_program_done();
+	dpkg_locales_done();
+
+	return ret;
+}