Esempio n. 1
0
static int files_fileowner(alpm_list_t *syncs, alpm_list_t *targets) {
	int ret = 0;
	alpm_list_t *t;

	for(t = targets; t; t = alpm_list_next(t)) {
		char *filename = NULL, *f;
		int found = 0;
		alpm_list_t *s;
		size_t len;

		if((filename = strdup(t->data)) == NULL) {
			goto notfound;
		}

		len = strlen(filename);
		f = filename;
		while(len > 1 && f[0] == '/') {
			f = f + 1;
			len--;
		}

		for(s = syncs; s; s = alpm_list_next(s)) {
			alpm_list_t *p;
			alpm_db_t *repo = s->data;
			alpm_list_t *packages = alpm_db_get_pkgcache(repo);

			for(p = packages; p; p = alpm_list_next(p)) {
				alpm_pkg_t *pkg = p->data;
				alpm_filelist_t *files = alpm_pkg_get_files(pkg);

				if(alpm_filelist_contains(files, f)) {

					if(!config->quiet) {
						printf(_("%s is owned by %s/%s %s\n"), f,
								alpm_db_get_name(repo), alpm_pkg_get_name(pkg),
								alpm_pkg_get_version(pkg));
					} else {
						printf("%s/%s\n", alpm_db_get_name(repo), alpm_pkg_get_name(pkg));
					}

					found = 1;
				}
			}
		}

		free(filename);

notfound:
		if(!found) {
			ret++;
		}
	}

	return 0;
}
Esempio n. 2
0
static int files_fileowner(alpm_list_t *syncs, alpm_list_t *targets) {
	int ret = 0;
	alpm_list_t *t;

	for(t = targets; t; t = alpm_list_next(t)) {
		char *filename = t->data;
		int found = 0;
		alpm_list_t *s;
		size_t len = strlen(filename);

		while(len > 1 && filename[0] == '/') {
			filename++;
			len--;
		}

		for(s = syncs; s; s = alpm_list_next(s)) {
			alpm_list_t *p;
			alpm_db_t *repo = s->data;
			alpm_list_t *packages = alpm_db_get_pkgcache(repo);

			for(p = packages; p; p = alpm_list_next(p)) {
				alpm_pkg_t *pkg = p->data;
				alpm_filelist_t *files = alpm_pkg_get_files(pkg);

				if(alpm_filelist_contains(files, filename)) {
					if(config->op_f_machinereadable) {
						print_line_machinereadable(repo, pkg, filename);
					} else if(!config->quiet) {
						const colstr_t *colstr = &config->colstr;
						printf(_("%s is owned by %s%s/%s%s %s%s\n"), filename,
								colstr->repo, alpm_db_get_name(repo), colstr->title,
								alpm_pkg_get_name(pkg), colstr->version,
								alpm_pkg_get_version(pkg));
					} else {
						printf("%s/%s\n", alpm_db_get_name(repo), alpm_pkg_get_name(pkg));
					}

					found = 1;
				}
			}
		}

		if(!found) {
			ret++;
		}
	}

	return 0;
}
Esempio n. 3
0
static int extract_single_file(alpm_handle_t *handle, struct archive *archive,
		struct archive_entry *entry, alpm_pkg_t *newpkg, alpm_pkg_t *oldpkg)
{
	const char *entryname = archive_entry_pathname(entry);
	mode_t entrymode = archive_entry_mode(entry);
	alpm_backup_t *backup = _alpm_needbackup(entryname, newpkg);
	char filename[PATH_MAX]; /* the actual file we're extracting */
	int needbackup = 0, notouch = 0;
	const char *hash_orig = NULL;
	int isnewfile = 0, errors = 0;
	struct stat lsbuf;
	size_t filename_len;

	if(*entryname == '.') {
		return extract_db_file(handle, archive, entry, newpkg, entryname);
	}

	if (!alpm_filelist_contains(&newpkg->files, entryname)) {
		_alpm_log(handle, ALPM_LOG_WARNING,
				_("file not found in file list for package %s. skipping extraction of %s\n"),
				newpkg->name, entryname);
		return 0;
	}

	/* build the new entryname relative to handle->root */
	filename_len = snprintf(filename, PATH_MAX, "%s%s", handle->root, entryname);
	if(filename_len >= PATH_MAX) {
		_alpm_log(handle, ALPM_LOG_ERROR,
				_("unable to extract %s%s: path too long"), handle->root, entryname);
		return 1;
	}

	/* if a file is in NoExtract then we never extract it */
	if(_alpm_fnmatch_patterns(handle->noextract, entryname) == 0) {
		_alpm_log(handle, ALPM_LOG_DEBUG, "%s is in NoExtract,"
				" skipping extraction of %s\n",
				entryname, filename);
		archive_read_data_skip(archive);
		return 0;
	}

	/* Check for file existence. This is one of the more crucial parts
	 * to get 'right'. Here are the possibilities, with the filesystem
	 * on the left and the package on the top:
	 * (F=file, N=node, S=symlink, D=dir)
	 *               |  F/N  |   D
	 *  non-existent |   1   |   2
	 *  F/N          |   3   |   4
	 *  D            |   5   |   6
	 *
	 *  1,2- extract, no magic necessary. lstat (llstat) will fail here.
	 *  3,4- conflict checks should have caught this. either overwrite
	 *      or backup the file.
	 *  5- file replacing directory- don't allow it.
	 *  6- skip extraction, dir already exists.
	 */

	isnewfile = llstat(filename, &lsbuf) != 0;
	if(isnewfile) {
		/* cases 1,2: file doesn't exist, skip all backup checks */
	} else if(S_ISDIR(lsbuf.st_mode) && S_ISDIR(entrymode)) {
#if 0
		uid_t entryuid = archive_entry_uid(entry);
		gid_t entrygid = archive_entry_gid(entry);
#endif

		/* case 6: existing dir, ignore it */
		if(lsbuf.st_mode != entrymode) {
			/* if filesystem perms are different than pkg perms, warn user */
			mode_t mask = 07777;
			_alpm_log(handle, ALPM_LOG_WARNING, _("directory permissions differ on %s\n"
					"filesystem: %o  package: %o\n"), filename, lsbuf.st_mode & mask,
					entrymode & mask);
			alpm_logaction(handle, ALPM_CALLER_PREFIX,
					"warning: directory permissions differ on %s\n"
					"filesystem: %o  package: %o\n", filename, lsbuf.st_mode & mask,
					entrymode & mask);
		}
#ifndef __MSYS__

#if 0
		/* Disable this warning until our user management in packages has improved.
		   Currently many packages have to create users in post_install and chown the
		   directories. These all resulted in "false-positive" warnings. */

		if((entryuid != lsbuf.st_uid) || (entrygid != lsbuf.st_gid)) {
			_alpm_log(handle, ALPM_LOG_WARNING, _("directory ownership differs on %s\n"
					"filesystem: %u:%u  package: %u:%u\n"), filename,
					lsbuf.st_uid, lsbuf.st_gid, entryuid, entrygid);
			alpm_logaction(handle, ALPM_CALLER_PREFIX,
					"warning: directory ownership differs on %s\n"
					"filesystem: %u:%u  package: %u:%u\n", filename,
					lsbuf.st_uid, lsbuf.st_gid, entryuid, entrygid);
		}
#endif

#endif
		_alpm_log(handle, ALPM_LOG_DEBUG, "extract: skipping dir extraction of %s\n",
				filename);
		archive_read_data_skip(archive);
		return 0;
	} else if(S_ISDIR(lsbuf.st_mode)) {
		/* case 5: trying to overwrite dir with file, don't allow it */
		_alpm_log(handle, ALPM_LOG_ERROR, _("extract: not overwriting dir with file %s\n"),
				filename);
		archive_read_data_skip(archive);
		return 1;
	} else if(S_ISDIR(entrymode)) {
		/* case 4: trying to overwrite file with dir */
		_alpm_log(handle, ALPM_LOG_DEBUG, "extract: overwriting file with dir %s\n",
				filename);
	} else {
		/* case 3: trying to overwrite file with file */
		/* if file is in NoUpgrade, don't touch it */
		if(_alpm_fnmatch_patterns(handle->noupgrade, entryname) == 0) {
			notouch = 1;
		} else {
			alpm_backup_t *oldbackup;
			if(oldpkg && (oldbackup = _alpm_needbackup(entryname, oldpkg))) {
				hash_orig = oldbackup->hash;
				needbackup = 1;
			} else if(backup) {
				/* allow adding backup files retroactively */
				needbackup = 1;
			}
		}
	}

	if(notouch || needbackup) {
		if(filename_len + strlen(".pacnew") >= PATH_MAX) {
			_alpm_log(handle, ALPM_LOG_ERROR,
					_("unable to extract %s.pacnew: path too long"), filename);
			return 1;
		}
		strcpy(filename + filename_len, ".pacnew");
		isnewfile = (llstat(filename, &lsbuf) != 0 && errno == ENOENT);
	}

	_alpm_log(handle, ALPM_LOG_DEBUG, "extracting %s\n", filename);
	if(perform_extraction(handle, archive, entry, filename)) {
		errors++;
		return errors;
	}

	if(backup) {
		FREE(backup->hash);
		backup->hash = alpm_compute_md5sum(filename);
	}

	if(notouch) {
		alpm_event_pacnew_created_t event = {
			.type = ALPM_EVENT_PACNEW_CREATED,
			.from_noupgrade = 1,
			.oldpkg = oldpkg,
			.newpkg = newpkg,
			.file = filename
		};
		/* "remove" the .pacnew suffix */
		filename[filename_len] = '\0';
		EVENT(handle, &event);
		alpm_logaction(handle, ALPM_CALLER_PREFIX,
				"warning: %s installed as %s.pacnew\n", filename, filename);
	} else if(needbackup) {
		char *hash_local = NULL, *hash_pkg = NULL;
		char origfile[PATH_MAX] = "";

		strncat(origfile, filename, filename_len);

		hash_local = alpm_compute_md5sum(origfile);
		hash_pkg = backup ? backup->hash : alpm_compute_md5sum(filename);

		_alpm_log(handle, ALPM_LOG_DEBUG, "checking hashes for %s\n", origfile);
		_alpm_log(handle, ALPM_LOG_DEBUG, "current:  %s\n", hash_local);
		_alpm_log(handle, ALPM_LOG_DEBUG, "new:      %s\n", hash_pkg);
		_alpm_log(handle, ALPM_LOG_DEBUG, "original: %s\n", hash_orig);

		if(hash_local && hash_pkg && strcmp(hash_local, hash_pkg) == 0) {
			/* local and new files are the same, updating anyway to get
			 * correct timestamps */
			_alpm_log(handle, ALPM_LOG_DEBUG, "action: installing new file: %s\n",
					origfile);
			if(try_rename(handle, filename, origfile)) {
				errors++;
			}
		} else if(hash_orig && hash_pkg && strcmp(hash_orig, hash_pkg) == 0) {
			/* original and new files are the same, leave the local version alone,
			 * including any user changes */
			_alpm_log(handle, ALPM_LOG_DEBUG,
					"action: leaving existing file in place\n");
			if(isnewfile) {
				unlink(filename);
			}
		} else if(hash_orig && hash_local && strcmp(hash_orig, hash_local) == 0) {
			/* installed file has NOT been changed by user,
			 * update to the new version */
			_alpm_log(handle, ALPM_LOG_DEBUG, "action: installing new file: %s\n",
					origfile);
			if(try_rename(handle, filename, origfile)) {
				errors++;
			}
		} else {
			/* none of the three files matched another,  leave the unpacked
			 * file alongside the local file */
			alpm_event_pacnew_created_t event = {
				.type = ALPM_EVENT_PACNEW_CREATED,
				.from_noupgrade = 0,
				.oldpkg = oldpkg,
				.newpkg = newpkg,
				.file = origfile
			};
			_alpm_log(handle, ALPM_LOG_DEBUG,
					"action: keeping current file and installing"
					" new one with .pacnew ending\n");
			EVENT(handle, &event);
			alpm_logaction(handle, ALPM_CALLER_PREFIX,
					"warning: %s installed as %s\n", origfile, filename);
		}

		free(hash_local);
		if(!backup) {
			free(hash_pkg);
		}
	}
	return errors;
}

static int commit_single_pkg(alpm_handle_t *handle, alpm_pkg_t *newpkg,
		size_t pkg_current, size_t pkg_count)
{
	int i, ret = 0, errors = 0;
	int is_upgrade = 0;
	alpm_pkg_t *oldpkg = NULL;
	alpm_db_t *db = handle->db_local;
	alpm_trans_t *trans = handle->trans;
	alpm_progress_t progress = ALPM_PROGRESS_ADD_START;
	alpm_event_package_operation_t event;
	const char *log_msg = "adding";
	const char *pkgfile;

	ASSERT(trans != NULL, return -1);

	/* see if this is an upgrade. if so, remove the old package first */
	if((oldpkg = newpkg->oldpkg)) {
		int cmp = _alpm_pkg_compare_versions(newpkg, oldpkg);
		if(cmp < 0) {
			log_msg = "downgrading";
			progress = ALPM_PROGRESS_DOWNGRADE_START;
			event.operation = ALPM_PACKAGE_DOWNGRADE;
		} else if(cmp == 0) {
			log_msg = "reinstalling";
			progress = ALPM_PROGRESS_REINSTALL_START;
			event.operation = ALPM_PACKAGE_REINSTALL;
		} else {
			log_msg = "upgrading";
			progress = ALPM_PROGRESS_UPGRADE_START;
			event.operation = ALPM_PACKAGE_UPGRADE;
		}
		is_upgrade = 1;

		/* copy over the install reason */
		newpkg->reason = alpm_pkg_get_reason(oldpkg);
	} else {
		event.operation = ALPM_PACKAGE_INSTALL;
	}

	event.type = ALPM_EVENT_PACKAGE_OPERATION_START;
	event.oldpkg = oldpkg;
	event.newpkg = newpkg;
	EVENT(handle, &event);

	pkgfile = newpkg->origin_data.file;

	_alpm_log(handle, ALPM_LOG_DEBUG, "%s package %s-%s\n",
			log_msg, newpkg->name, newpkg->version);
		/* pre_install/pre_upgrade scriptlet */
	if(alpm_pkg_has_scriptlet(newpkg) &&
			!(trans->flags & ALPM_TRANS_FLAG_NOSCRIPTLET)) {
		const char *scriptlet_name = is_upgrade ? "pre_upgrade" : "pre_install";

		_alpm_runscriptlet(handle, pkgfile, scriptlet_name,
				newpkg->version, oldpkg ? oldpkg->version : NULL, 1);
	}

	/* we override any pre-set reason if we have alldeps or allexplicit set */
	if(trans->flags & ALPM_TRANS_FLAG_ALLDEPS) {
		newpkg->reason = ALPM_PKG_REASON_DEPEND;
	} else if(trans->flags & ALPM_TRANS_FLAG_ALLEXPLICIT) {
		newpkg->reason = ALPM_PKG_REASON_EXPLICIT;
	}

	if(oldpkg) {
		/* set up fake remove transaction */
		if(_alpm_remove_single_package(handle, oldpkg, newpkg, 0, 0) == -1) {
			handle->pm_errno = ALPM_ERR_TRANS_ABORT;
			ret = -1;
			goto cleanup;
		}
	}

	/* prepare directory for database entries so permission are correct after
	   changelog/install script installation */
	if(_alpm_local_db_prepare(db, newpkg)) {
		alpm_logaction(handle, ALPM_CALLER_PREFIX,
				"error: could not create database entry %s-%s\n",
				newpkg->name, newpkg->version);
		handle->pm_errno = ALPM_ERR_DB_WRITE;
		ret = -1;
		goto cleanup;
	}

	if(!(trans->flags & ALPM_TRANS_FLAG_DBONLY)) {
		struct archive *archive;
		struct archive_entry *entry;
		struct stat buf;
		int fd, cwdfd;

		_alpm_log(handle, ALPM_LOG_DEBUG, "extracting files\n");

		fd = _alpm_open_archive(db->handle, pkgfile, &buf,
				&archive, ALPM_ERR_PKG_OPEN);
		if(fd < 0) {
			ret = -1;
			goto cleanup;
		}

		/* save the cwd so we can restore it later */
		OPEN(cwdfd, ".", O_RDONLY | O_CLOEXEC);
		if(cwdfd < 0) {
			_alpm_log(handle, ALPM_LOG_ERROR, _("could not get current working directory\n"));
		}

		/* libarchive requires this for extracting hard links */
		if(chdir(handle->root) != 0) {
			_alpm_log(handle, ALPM_LOG_ERROR, _("could not change directory to %s (%s)\n"),
					handle->root, strerror(errno));
			_alpm_archive_read_free(archive);
			close(fd);
			ret = -1;
			goto cleanup;
		}

		/* call PROGRESS once with 0 percent, as we sort-of skip that here */
		PROGRESS(handle, progress, newpkg->name, 0, pkg_count, pkg_current);

		for(i = 0; archive_read_next_header(archive, &entry) == ARCHIVE_OK; i++) {
			int percent;

			if(newpkg->size != 0) {
				/* Using compressed size for calculations here, as newpkg->isize is not
				 * exact when it comes to comparing to the ACTUAL uncompressed size
				 * (missing metadata sizes) */
				int64_t pos = _alpm_archive_compressed_ftell(archive);
				percent = (pos * 100) / newpkg->size;
				if(percent >= 100) {
					percent = 100;
				}
			} else {
				percent = 0;
			}

			PROGRESS(handle, progress, newpkg->name, percent, pkg_count, pkg_current);

			/* extract the next file from the archive */
			errors += extract_single_file(handle, archive, entry, newpkg, oldpkg);
		}
		_alpm_archive_read_free(archive);
		close(fd);

		/* restore the old cwd if we have it */
		if(cwdfd >= 0) {
			if(fchdir(cwdfd) != 0) {
				_alpm_log(handle, ALPM_LOG_ERROR,
						_("could not restore working directory (%s)\n"), strerror(errno));
			}
			close(cwdfd);
		}

		if(errors) {
			ret = -1;
			if(is_upgrade) {
				_alpm_log(handle, ALPM_LOG_ERROR, _("problem occurred while upgrading %s\n"),
						newpkg->name);
				alpm_logaction(handle, ALPM_CALLER_PREFIX,
						"error: problem occurred while upgrading %s\n",
						newpkg->name);
			} else {
				_alpm_log(handle, ALPM_LOG_ERROR, _("problem occurred while installing %s\n"),
						newpkg->name);
				alpm_logaction(handle, ALPM_CALLER_PREFIX,
						"error: problem occurred while installing %s\n",
						newpkg->name);
			}
		}
	}

	/* make an install date (in UTC) */
	newpkg->installdate = time(NULL);

	_alpm_log(handle, ALPM_LOG_DEBUG, "updating database\n");
	_alpm_log(handle, ALPM_LOG_DEBUG, "adding database entry '%s'\n", newpkg->name);

	if(_alpm_local_db_write(db, newpkg, INFRQ_ALL)) {
		_alpm_log(handle, ALPM_LOG_ERROR, _("could not update database entry %s-%s\n"),
				newpkg->name, newpkg->version);
		alpm_logaction(handle, ALPM_CALLER_PREFIX,
				"error: could not update database entry %s-%s\n",
				newpkg->name, newpkg->version);
		handle->pm_errno = ALPM_ERR_DB_WRITE;
		ret = -1;
		goto cleanup;
	}

	if(_alpm_db_add_pkgincache(db, newpkg) == -1) {
		_alpm_log(handle, ALPM_LOG_ERROR, _("could not add entry '%s' in cache\n"),
				newpkg->name);
	}

	PROGRESS(handle, progress, newpkg->name, 100, pkg_count, pkg_current);

	switch(event.operation) {
		case ALPM_PACKAGE_INSTALL:
			alpm_logaction(handle, ALPM_CALLER_PREFIX, "installed %s (%s)\n",
					newpkg->name, newpkg->version);
			break;
		case ALPM_PACKAGE_DOWNGRADE:
			alpm_logaction(handle, ALPM_CALLER_PREFIX, "downgraded %s (%s -> %s)\n",
					newpkg->name, oldpkg->version, newpkg->version);
			break;
		case ALPM_PACKAGE_REINSTALL:
			alpm_logaction(handle, ALPM_CALLER_PREFIX, "reinstalled %s (%s)\n",
					newpkg->name, newpkg->version);
			break;
		case ALPM_PACKAGE_UPGRADE:
			alpm_logaction(handle, ALPM_CALLER_PREFIX, "upgraded %s (%s -> %s)\n",
					newpkg->name, oldpkg->version, newpkg->version);
			break;
		default:
			/* we should never reach here */
			break;
	}

	/* run the post-install script if it exists */
	if(alpm_pkg_has_scriptlet(newpkg)
			&& !(trans->flags & ALPM_TRANS_FLAG_NOSCRIPTLET)) {
		char *scriptlet = _alpm_local_db_pkgpath(db, newpkg, "install");
		const char *scriptlet_name = is_upgrade ? "post_upgrade" : "post_install";

		_alpm_runscriptlet(handle, scriptlet, scriptlet_name,
				newpkg->version, oldpkg ? oldpkg->version : NULL, 0);
		free(scriptlet);
	}

	event.type = ALPM_EVENT_PACKAGE_OPERATION_DONE;
	EVENT(handle, &event);

cleanup:
	return ret;
}
Esempio n. 4
0
/**
 * @brief Remove a package's files, optionally skipping its replacement's
 * files.
 *
 * @param handle the context handle
 * @param oldpkg package to remove
 * @param newpkg package to replace \a oldpkg (optional)
 * @param targ_count current index within the transaction (1-based)
 * @param pkg_count the number of packages affected by the transaction
 *
 * @return 0 on success, -1 if alpm lacks permission to delete some of the
 * files, >0 the number of files alpm was unable to delete
 */
static int remove_package_files(alpm_handle_t *handle,
		alpm_pkg_t *oldpkg, alpm_pkg_t *newpkg,
		size_t targ_count, size_t pkg_count)
{
	alpm_list_t *skip_remove;
	alpm_filelist_t *filelist;
	size_t i;
	int err = 0;
	int nosave = handle->trans->flags & ALPM_TRANS_FLAG_NOSAVE;

	if(newpkg) {
		alpm_filelist_t *newfiles;
		alpm_list_t *b;
		skip_remove = alpm_list_join(
				alpm_list_strdup(handle->trans->skip_remove),
				alpm_list_strdup(handle->noupgrade));
		/* Add files in the NEW backup array to the skip_remove array
		 * so this removal operation doesn't kill them */
		/* old package backup list */
		newfiles = alpm_pkg_get_files(newpkg);
		for(b = alpm_pkg_get_backup(newpkg); b; b = b->next) {
			const alpm_backup_t *backup = b->data;
			/* safety check (fix the upgrade026 pactest) */
			if(!alpm_filelist_contains(newfiles, backup->name)) {
				continue;
			}
			_alpm_log(handle, ALPM_LOG_DEBUG, "adding %s to the skip_remove array\n",
					backup->name);
			skip_remove = alpm_list_add(skip_remove, strdup(backup->name));
		}
	} else {
		skip_remove = alpm_list_strdup(handle->trans->skip_remove);
	}

	filelist = alpm_pkg_get_files(oldpkg);
	for(i = 0; i < filelist->count; i++) {
		alpm_file_t *file = filelist->files + i;
		if(!can_remove_file(handle, file, skip_remove)) {
			_alpm_log(handle, ALPM_LOG_DEBUG,
					"not removing package '%s', can't remove all files\n",
					oldpkg->name);
			FREELIST(skip_remove);
			RET_ERR(handle, ALPM_ERR_PKG_CANT_REMOVE, -1);
		}
	}

	_alpm_log(handle, ALPM_LOG_DEBUG, "removing %zd files\n", filelist->count);

	if(!newpkg) {
		/* init progress bar, but only on true remove transactions */
		PROGRESS(handle, ALPM_PROGRESS_REMOVE_START, oldpkg->name, 0,
				pkg_count, targ_count);
	}

	/* iterate through the list backwards, unlinking files */
	for(i = filelist->count; i > 0; i--) {
		alpm_file_t *file = filelist->files + i - 1;
		if(unlink_file(handle, oldpkg, newpkg, file, skip_remove, nosave) < 0) {
			err++;
		}

		if(!newpkg) {
			/* update progress bar after each file */
			int percent = ((filelist->count - i) * 100) / filelist->count;
			PROGRESS(handle, ALPM_PROGRESS_REMOVE_START, oldpkg->name,
					percent, pkg_count, targ_count);
		}
	}
	FREELIST(skip_remove);

	if(!newpkg) {
		/* set progress to 100% after we finish unlinking files */
		PROGRESS(handle, ALPM_PROGRESS_REMOVE_START, oldpkg->name, 100,
				pkg_count, targ_count);
	}

	return err;
}
Esempio n. 5
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/**
 * @brief Unlink a package file, backing it up if necessary.
 *
 * @param handle the context handle
 * @param oldpkg the package being removed
 * @param newpkg the package replacing \a oldpkg
 * @param fileobj file to remove
 * @param skip_remove list of files that shouldn't be removed
 * @param nosave whether files should be backed up
 *
 * @return 0 on success, -1 if there was an error unlinking the file, 1 if the
 * file was skipped or did not exist
 */
static int unlink_file(alpm_handle_t *handle, alpm_pkg_t *oldpkg,
		alpm_pkg_t *newpkg, const alpm_file_t *fileobj, alpm_list_t *skip_remove,
		int nosave)
{
	struct stat buf;
	char file[PATH_MAX];

	snprintf(file, PATH_MAX, "%s%s", handle->root, fileobj->name);

	/* check the remove skip list before removing the file.
	 * see the big comment block in db_find_fileconflicts() for an
	 * explanation. */
	if(alpm_list_find(skip_remove, fileobj->name, _alpm_fnmatch)) {
		_alpm_log(handle, ALPM_LOG_DEBUG,
				"%s is in skip_remove, skipping removal\n", file);
		return 1;
	}

	if(_alpm_lstat(file, &buf)) {
		_alpm_log(handle, ALPM_LOG_DEBUG, "file %s does not exist\n", file);
		return 1;
	}

	if(S_ISDIR(buf.st_mode)) {
		ssize_t files = _alpm_files_in_directory(handle, file, 0);
		/* if we have files, no need to remove the directory */
		if(files > 0) {
			_alpm_log(handle, ALPM_LOG_DEBUG, "keeping directory %s (contains files)\n",
					file);
		} else if(files < 0) {
			_alpm_log(handle, ALPM_LOG_DEBUG,
					"keeping directory %s (could not count files)\n", file);
		} else if(newpkg && alpm_filelist_contains(alpm_pkg_get_files(newpkg),
					fileobj->name)) {
			_alpm_log(handle, ALPM_LOG_DEBUG,
					"keeping directory %s (in new package)\n", file);
		} else if(dir_is_mountpoint(handle, file, &buf)) {
			_alpm_log(handle, ALPM_LOG_DEBUG,
					"keeping directory %s (mountpoint)\n", file);
		} else {
			/* one last check- does any other package own this file? */
			alpm_list_t *local, *local_pkgs;
			int found = 0;
			local_pkgs = _alpm_db_get_pkgcache(handle->db_local);
			for(local = local_pkgs; local && !found; local = local->next) {
				alpm_pkg_t *local_pkg = local->data;
				alpm_filelist_t *filelist;

				/* we duplicated the package when we put it in the removal list, so we
				 * so we can't use direct pointer comparison here. */
				if(oldpkg->name_hash == local_pkg->name_hash
						&& strcmp(oldpkg->name, local_pkg->name) == 0) {
					continue;
				}
				filelist = alpm_pkg_get_files(local_pkg);
				if(alpm_filelist_contains(filelist, fileobj->name)) {
					_alpm_log(handle, ALPM_LOG_DEBUG,
							"keeping directory %s (owned by %s)\n", file, local_pkg->name);
					found = 1;
				}
			}
			if(!found) {
				if(rmdir(file)) {
					_alpm_log(handle, ALPM_LOG_DEBUG,
							"directory removal of %s failed: %s\n", file, strerror(errno));
					return -1;
				} else {
					_alpm_log(handle, ALPM_LOG_DEBUG,
							"removed directory %s (no remaining owners)\n", file);
				}
			}
		}
	} else {
		/* if the file needs backup and has been modified, back it up to .pacsave */
		alpm_backup_t *backup = _alpm_needbackup(fileobj->name, oldpkg);
		if(backup) {
			if(nosave) {
				_alpm_log(handle, ALPM_LOG_DEBUG, "transaction is set to NOSAVE, not backing up '%s'\n", file);
			} else {
				char *filehash = alpm_compute_md5sum(file);
				int cmp = filehash ? strcmp(filehash, backup->hash) : 0;
				FREE(filehash);
				if(cmp != 0) {
					char *newpath;
					size_t len = strlen(file) + 8 + 1;
					MALLOC(newpath, len, RET_ERR(handle, ALPM_ERR_MEMORY, -1));
					shift_pacsave(handle, file);
					snprintf(newpath, len, "%s.pacsave", file);
					if(rename(file, newpath)) {
						_alpm_log(handle, ALPM_LOG_ERROR, _("could not rename %s to %s (%s)\n"),
								file, newpath, strerror(errno));
						alpm_logaction(handle, ALPM_CALLER_PREFIX,
								"error: could not rename %s to %s (%s)\n",
								file, newpath, strerror(errno));
						free(newpath);
						return -1;
					}
					_alpm_log(handle, ALPM_LOG_WARNING, _("%s saved as %s\n"), file, newpath);
					alpm_logaction(handle, ALPM_CALLER_PREFIX,
							"warning: %s saved as %s\n", file, newpath);
					free(newpath);
					return 0;
				}
			}
		}

		_alpm_log(handle, ALPM_LOG_DEBUG, "unlinking %s\n", file);

		if(unlink(file) == -1) {
			_alpm_log(handle, ALPM_LOG_ERROR, _("cannot remove %s (%s)\n"),
					file, strerror(errno));
			alpm_logaction(handle, ALPM_CALLER_PREFIX,
					"error: cannot remove %s (%s)\n", file, strerror(errno));
			return -1;
		}
	}
	return 0;
}