Fix #50 (Existent files on disk might be overwritten by packages with conf_files).

NEWS

@@ -1,5 +1,9 @@
 xbps-0.38 (???):
 
+ * Always preserve files that exist on disk, but are managed by a package.
+   When such condition ocurrs install the pkg configuration file as `file.new-<version>`.
+   This fixes GH issue #50 https://github.com/voidlinux/xbps/issues/50.
+
  * Implemented support for post-install and pre-remove messages, as explained
    in issue #44 https://github.com/voidlinux/xbps/issues/44.
 

lib/package_config_files.c

@@ -68,7 +68,7 @@ xbps_entry_install_conf_file(struct xbps_handle *xhp,
 	xbps_dictionary_t forigd;
 	xbps_object_t obj, obj2;
 	xbps_object_iterator_t iter, iter2;
-	const char *cffile, *sha256_new = NULL;
+	const char *version = NULL, *cffile, *sha256_new = NULL;
 	char buf[PATH_MAX], *sha256_cur = NULL, *sha256_orig = NULL;
 	int rv = 0;
 
@@ -90,8 +90,18 @@ xbps_entry_install_conf_file(struct xbps_handle *xhp,
 
 	forigd = xbps_pkgdb_get_pkg_metadata(xhp, pkgname);
 	if (forigd == NULL) {
+		/*
+		 * File exists on disk but it's not managed by the same package.
+		 * Install it as file.new-<version>.
+		 */
+		version = xbps_pkg_version(pkgver);
+		assert(version);
 		xbps_dbg_printf(xhp, "%s: conf_file %s not currently "
-		    "installed\n", pkgver, entry_pname);
+		    "installed, renaming to %s.new-%s\n", pkgver, entry_pname, version);
+		snprintf(buf, sizeof(buf), "%s.new-%s", entry_pname, version);
+		xbps_set_cb_state(xhp, XBPS_STATE_CONFIG_FILE,
+		    0, pkgver, "File `%s' exists, installing configuration file to `%s'.", entry_pname, buf);
+		archive_entry_copy_pathname(entry, buf);
 		rv = 1;
 		goto out;
 	}
@@ -207,13 +217,11 @@ xbps_entry_install_conf_file(struct xbps_handle *xhp,
 		} else  if ((strcmp(sha256_orig, sha256_cur)) &&
 			    (strcmp(sha256_cur, sha256_new)) &&
 			    (strcmp(sha256_orig, sha256_new))) {
-			const char *version;
-
 			version = xbps_pkg_version(pkgver);
 			assert(version);
 			snprintf(buf, sizeof(buf), ".%s.new-%s", cffile, version);
 			xbps_set_cb_state(xhp, XBPS_STATE_CONFIG_FILE,
-			    0, pkgver, "Installing new configuration file to `%s'.", buf);
+			    0, pkgver, "File `%s' exists, installing configuration file to `%s'.", cffile, buf);
 			archive_entry_copy_pathname(entry, buf);
 			rv = 1;
 			break;

lib/package_unpack.c

@@ -410,8 +410,8 @@ unpack_archive(struct xbps_handle *xhp,
 						    "matches existing SHA256, "
 						    "skipping...\n",
 						    pkgver, entry_pname);
-						skip_extract = true;
 					}
+					skip_extract = true;
 					rv = 0;
 				}
 			}
@@ -497,20 +497,6 @@ unpack_archive(struct xbps_handle *xhp,
 			    "mode to %s.\n", pkgver, entry_pname,
 			    archive_entry_strmode(entry));
 		}
-		if (!update && conf_file && file_exists && !skip_extract) {
-			/*
-			 * If installing new package preserve old configuration
-			 * file but renaming it to <file>.old.
-			 */
-			buf = xbps_xasprintf("%s.old", entry_pname);
-			(void)rename(entry_pname, buf);
-			free(buf);
-			buf = NULL;
-			xbps_set_cb_state(xhp,
-			    XBPS_STATE_CONFIG_FILE, 0, pkgver,
-			    "Renamed old configuration file "
-			    "`%s' to `%s.old'.", entry_pname, entry_pname);
-		}
 		if (!force && skip_extract) {
 			archive_read_data_skip(ar);
 			continue;

tests/xbps/libxbps/shell/conf_files_test.sh

@@ -128,8 +128,44 @@ tc3_body() {
 	atf_check_equal $rval 0
 }
 
+# 4th test: existent file on disk; new package defines configuration file.
+#	result: keep on-disk file as is, install new conf file as file.new-<version>.
+atf_test_case tc4
+
+tc4_head() {
+	atf_set "descr" "Tests for configuration file handling: existent on-disk, new install"
+}
+
+tc4_body() {
+	mkdir repo
+	cd repo
+	mkdir -p pkg_a/etc
+	echo "fooblah" > pkg_a/etc/cf1.conf
+	chmod 755 pkg_a/etc/cf1.conf
+	xbps-create -A noarch -n a-0.1_1 -s "pkg a" --config-files "/etc/cf1.conf" pkg_a
+	atf_check_equal $? 0
+	rm -rf pkg_a
+	xbps-rindex -a *.xbps
+	atf_check_equal $? 0
+
+	mkdir -p rootdir/etc
+	echo "blahblah" > rootdir/etc/cf1.conf
+
+	xbps-install -C null.conf -r rootdir --repository=$PWD -yvd a
+	atf_check_equal $? 0
+
+	result="$(cat rootdir/etc/cf1.conf)"
+	resultpkg="$(cat rootdir/etc/cf1.conf.new-0.1_1)"
+	rval=1
+	if [ "${result}" = "blahblah" -a "${resultpkg}" = "fooblah" ]; then
+		rval=0
+	fi
+	atf_check_equal $rval 0
+}
+
 atf_init_test_cases() {
 	atf_add_test_case tc1
 	atf_add_test_case tc2
 	atf_add_test_case tc3
+	atf_add_test_case tc4
 }