db: prepare database reading for layers

src/apk_database.h

@@ -115,6 +115,10 @@ struct apk_repository {
 	apk_blob_t description;
 };
 
+#define APK_DB_LAYER_ROOT		0
+#define APK_DB_LAYER_UVOL		1
+#define APK_DB_LAYER_NUM		2
+
 #define APK_REPOSITORY_CACHED		0
 #define APK_REPOSITORY_FIRST_CONFIGURED	1
 
@@ -138,6 +142,7 @@ struct apk_database {
 	unsigned int repo_update_errors, repo_update_counter;
 	unsigned int pending_triggers;
 	unsigned int extract_flags;
+	unsigned int active_layers;
 	int performing_self_upgrade : 1;
 	int permanent : 1;
 	int autoupdate : 1;
@@ -189,6 +194,7 @@ struct apk_db_dir *apk_db_dir_query(struct apk_database *db, apk_blob_t name);
 struct apk_db_file *apk_db_file_query(struct apk_database *db,
 				      apk_blob_t dir, apk_blob_t name);
 
+const char *apk_db_layer_name(int layer);
 void apk_db_init(struct apk_database *db);
 int apk_db_open(struct apk_database *db, struct apk_ctx *ctx);
 void apk_db_close(struct apk_database *db);

src/apk_package.h

@@ -93,6 +93,7 @@ struct apk_package {
 	unsigned marked : 1;
 	unsigned uninstallable : 1;
 	unsigned cached_non_repository : 1;
+	unsigned layer : 4;
 	struct apk_checksum csum;
 };
 APK_ARRAY(apk_package_array, struct apk_package *);

src/app_policy.c

@@ -13,8 +13,6 @@
 #include "apk_version.h"
 #include "apk_print.h"
 
-extern const char * const apk_installed_file;
-
 static void print_policy(struct apk_database *db, const char *match, struct apk_name *name, void *ctx)
 {
 	struct apk_out *out = &db->ctx->out;
@@ -44,8 +42,8 @@ zlib1g policy:
 		if (num++ == 0)
 			apk_out(out, "%s policy:", name->name);
 		apk_out(out, "  " BLOB_FMT ":", BLOB_PRINTF(*p->version));
-		if (p->pkg->ipkg != NULL)
+		if (p->pkg->ipkg)
-			apk_out(out, "    %s", apk_installed_file);
+			apk_out(out, "    %s/installed", apk_db_layer_name(p->pkg->layer));
 		for (i = 0; i < db->num_repos; i++) {
 			repo = &db->repos[i];
 			if (!(BIT(i) & p->pkg->repos))

src/database.c

@@ -56,9 +56,6 @@ static const char * const apk_static_cache_dir = "var/cache/apk";
 static const char * const apk_world_file = "etc/apk/world";
 static const char * const apk_arch_file = "etc/apk/arch";
 static const char * const apk_lock_file = "lib/apk/db/lock";
-static const char * const apk_scripts_file = "lib/apk/db/scripts.tar";
-static const char * const apk_triggers_file = "lib/apk/db/triggers";
-const char * const apk_installed_file = "lib/apk/db/installed";
 
 static struct apk_db_acl *apk_default_acl_dir, *apk_default_acl_file;
 
@@ -759,7 +756,7 @@ err:
 	return apk_istream_close(is);
 }
 
-int apk_db_index_read(struct apk_database *db, struct apk_istream *is, int repo)
+static int apk_db_fdb_read(struct apk_database *db, struct apk_istream *is, int repo, unsigned layer)
 {
 	struct apk_out *out = &db->ctx->out;
 	struct apk_package *pkg = NULL;
@@ -812,6 +809,7 @@ int apk_db_index_read(struct apk_database *db, struct apk_istream *is, int repo)
 		/* If no package, create new */
 		if (pkg == NULL) {
 			pkg = apk_pkg_new();
+			pkg->layer = layer;
 			ipkg = NULL;
 			diri = NULL;
 			file_diri_node = NULL;
@@ -911,6 +909,11 @@ err_fmt:
 	return apk_istream_close(is);
 }
 
+int apk_db_index_read(struct apk_database *db, struct apk_istream *is, int repo)
+{
+	return apk_db_fdb_read(db, is, repo, 0);
+}
+
 static void apk_blob_push_db_acl(apk_blob_t *b, char field, struct apk_db_acl *acl)
 {
 	char hdr[2] = { field, ':' };
@@ -1171,21 +1174,29 @@ static int apk_db_triggers_read(struct apk_database *db, struct apk_istream *is)
 	return apk_istream_close(is);
 }
 
-static int apk_db_read_state(struct apk_database *db, int flags)
+static int apk_db_read_layer(struct apk_database *db, unsigned layer)
 {
 	apk_blob_t blob, world;
-	int r, ret = 0;
+	int r, fd, ret = 0, flags = db->ctx->open_flags;
 
 	/* Read:
-	 * 1. /etc/apk/world
+	 * 1. world
 	 * 2. installed packages db
 	 * 3. triggers db
 	 * 4. scripts db
 	 */
+
+	fd = openat(db->root_fd, apk_db_layer_name(layer), O_RDONLY | O_CLOEXEC);
+	if (fd < 0) return -errno;
+
 	if (!(flags & APK_OPENF_NO_WORLD)) {
-		blob = world = apk_blob_from_file(db->root_fd, apk_world_file);
+		if (layer == APK_DB_LAYER_ROOT)
-		if (!APK_BLOB_IS_NULL(blob)) {
+			world = apk_blob_from_file(db->root_fd, apk_world_file);
-			blob = apk_blob_trim(blob);
+		else
+			world = apk_blob_from_file(fd, "world");
+
+		if (!APK_BLOB_IS_NULL(world)) {
+			blob = apk_blob_trim(world);
 			apk_blob_pull_deps(&blob, db, &db->world);
 			free(world.ptr);
 		} else {
@@ -1194,18 +1205,19 @@ static int apk_db_read_state(struct apk_database *db, int flags)
 	}
 
 	if (!(flags & APK_OPENF_NO_INSTALLED)) {
-		r = apk_db_index_read(db, apk_istream_from_file(db->root_fd, apk_installed_file), -1);
+		r = apk_db_fdb_read(db, apk_istream_from_file(fd, "installed"), -1, layer);
-		if (r && r != -ENOENT) ret = r;
+		if (!ret && r != -ENOENT) ret = r;
-		r = apk_db_triggers_read(db, apk_istream_from_file(db->root_fd, apk_triggers_file));
+		r = apk_db_triggers_read(db, apk_istream_from_file(fd, "triggers"));
-		if (r && r != -ENOENT) ret = r;
+		if (!ret && r != -ENOENT) ret = r;
 	}
 
 	if (!(flags & APK_OPENF_NO_SCRIPTS)) {
-		r = apk_tar_parse(apk_istream_from_file(db->root_fd, apk_scripts_file),
+		r = apk_tar_parse(apk_istream_from_file(fd, "scripts.tar"),
 				  apk_read_script_archive_entry, db, db->id_cache);
-		if (r && r != -ENOENT) ret = r;
+		if (!ret && r != -ENOENT) ret = r;
 	}
 
+	close(fd);
 	return ret;
 }
 
@@ -1616,6 +1628,17 @@ static void unmount_proc(struct apk_database *db)
 }
 #endif
 
+const char *apk_db_layer_name(int layer)
+{
+	switch (layer) {
+	case APK_DB_LAYER_ROOT: return "lib/apk/db";
+	case APK_DB_LAYER_UVOL: return "lib/apk/db-uvol";
+	default:
+		assert("invalid layer");
+		return 0;
+	}
+}
+
 void apk_db_init(struct apk_database *db)
 {
 	memset(db, 0, sizeof(*db));
@@ -1637,7 +1660,7 @@ int apk_db_open(struct apk_database *db, struct apk_ctx *ac)
 	struct apk_out *out = &ac->out;
 	const char *msg = NULL;
 	apk_blob_t blob;
-	int r;
+	int r, i;
 
 	apk_default_acl_dir = apk_db_acl_atomize(db, 0755, 0, 0);
 	apk_default_acl_file = apk_db_acl_atomize(db, 0644, 0, 0);
@@ -1721,11 +1744,16 @@ int apk_db_open(struct apk_database *db, struct apk_ctx *ac)
 		apk_db_read_overlay(db, apk_istream_from_fd(STDIN_FILENO));
 	}
 
-	r = apk_db_read_state(db, ac->open_flags);
+	for (i = 0; i < APK_DB_LAYER_NUM; i++) {
-	if (r != 0 && !(r == -ENOENT && (ac->open_flags & APK_OPENF_CREATE))) {
+		r = apk_db_read_layer(db, i);
-		msg = "Unable to read database state";
+		if (r) {
+			if (i != 0) continue;
+			if (r == -ENOENT && (ac->open_flags & APK_OPENF_CREATE)) continue;
+			msg = "Unable to read database";
 			goto ret_r;
 		}
+		db->active_layers |= BIT(i);
+	}
 
 	if (!(ac->open_flags & APK_OPENF_NO_INSTALLED_REPO)) {
 		if (apk_db_cache_active(db)) {