state: rework changeset calculation algorithm

Calculate changesets directly by stabilizating the package graph instead of
recalculating the whole graph and then diffing (similar approach as seen
in 'smart' package manager). The algorithm is not complete: defferred
search space forking is missing. So you don't always get a solution on
complex graphs.

Benefits:
- usually the search state tree is smaller (less memory used)
- speed relational to changeset size, not database size (usually faster)
- touch only packages related to users request (can work on partitially
  broken state; upgrades only necessary packages, fixes #7)

Also implemented:
- command prompt to confirm operation if packages are deleted or downgraded
- requesting deletion of package suggests removal of all packages depending
  on the package being removed (you'll get list of packages that also get
  removed if you want package X removed)
- option --simulate to see what would have been done (mainly for testing)
- an untested implementation of versioned dependencies and conflicts

A lot has changed, so expect new bugs too.

1 files changed, 11 insertions, 40 deletions

diff --git a/src/database.c b/src/database.c
index 5506ebb..9bf34ba 100644
--- a/src/database.c
+++ b/src/database.c
@@ -154,6 +154,7 @@ struct apk_name *apk_db_get_name(struct apk_database *db, apk_blob_t name)
 		return NULL;
 
 	pn->name = apk_blob_cstr(name);
+	pn->id = db->name_id++;
 	apk_hash_insert(&db->available.names, pn);
 
 	return pn;
@@ -355,7 +356,6 @@ static struct apk_package *apk_db_pkg_add(struct apk_database *db, struct apk_pa
 	idb = apk_hash_get(&db->available.packages, APK_BLOB_BUF(pkg->csum));
 	if (idb == NULL) {
 		idb = pkg;
-		pkg->id = db->pkg_id++;
 		apk_hash_insert(&db->available.packages, pkg);
 		*apk_package_array_add(&pkg->name->pkgs) = pkg;
 		apk_db_pkg_rdepends(db, pkg);
@@ -393,7 +393,7 @@ static int apk_db_index_read(struct apk_database *db, struct apk_istream *is, in
 				if (repo != -1)
 					pkg->repos |= BIT(repo);
 				else
-					apk_pkg_set_state(db, pkg, APK_STATE_INSTALL);
+					apk_pkg_set_state(db, pkg, APK_PKG_INSTALLED);
 
 				if (apk_db_pkg_add(db, pkg) != pkg && repo == -1) {
 					apk_error("Installed database load failed");
@@ -573,6 +573,7 @@ static int apk_db_read_state(struct apk_database *db)
 {
 	struct apk_istream *is;
 	apk_blob_t blob;
+	int i;
 
 	/* Read:
 	 * 1. installed repository
@@ -590,6 +591,9 @@ static int apk_db_read_state(struct apk_database *db)
 	apk_deps_parse(db, &db->world, blob);
 	free(blob.ptr);
 
+	for (i = 0; i < db->world->num; i++)
+		db->world->item[i].name->flags |= APK_NAME_TOPLEVEL;
+
 	is = apk_istream_from_file("var/lib/apk/installed");
 	if (is != NULL) {
 		apk_db_index_read(db, is, -1);
@@ -742,7 +746,7 @@ struct write_ctx {
 	int fd;
 };
 
-static int apk_db_write_config(struct apk_database *db)
+int apk_db_write_config(struct apk_database *db)
 {
 	struct apk_ostream *os;
 
@@ -919,39 +923,6 @@ int apk_db_add_repository(apk_database_t _db, apk_blob_t repository)
 	return 0;
 }
 
-int apk_db_recalculate_and_commit(struct apk_database *db)
-{
-	struct apk_state *state;
-	int r;
-
-	state = apk_state_new(db);
-	r = apk_state_satisfy_deps(state, db->world);
-	if (r == 0) {
-		r = apk_state_purge_unneeded(state, db);
-		if (r != 0) {
-			apk_error("Failed to clean up state");
-			return r;
-		}
-
-		r = apk_state_commit(state, db);
-		if (r != 0) {
-			apk_error("Failed to commit changes");
-			return r;
-		}
-		apk_db_write_config(db);
-
-		apk_message("OK: %d packages, %d dirs, %d files",
-			    db->installed.stats.packages,
-			    db->installed.stats.dirs,
-			    db->installed.stats.files);
-	} else {
-		apk_error("Failed to build installation graph");
-	}
-	apk_state_unref(state);
-
-	return r;
-}
-
 static void extract_cb(void *_ctx, size_t progress)
 {
 	struct install_ctx *ctx = (struct install_ctx *) _ctx;
@@ -1069,7 +1040,7 @@ static int apk_db_install_archive_entry(void *_ctx,
 		if (file->diri != diri) {
 			opkg = file->diri->pkg;
 			if (opkg->name != pkg->name) {
-				if (!apk_force) {
+				if (!(apk_flags & APK_FORCE)) {
 					apk_error("%s: Trying to overwrite %s "
 						  "owned by %s.\n",
 						  pkg->name->name, ae->name,
@@ -1093,7 +1064,7 @@ static int apk_db_install_archive_entry(void *_ctx,
 		    (memcmp(file->csum, fi.csum, sizeof(csum_t)) != 0 ||
 		     !csum_valid(file->csum))) {
 			/* Protected file. Extract to separate place */
-			if (!apk_clean) {
+			if (!(apk_flags & APK_CLEAN_PROTECTED)) {
 				snprintf(alt_name, sizeof(alt_name),
 					 "%s/%s.apk-new",
 					 diri->dir->dirname, file->filename);
@@ -1160,7 +1131,7 @@ static void apk_db_purge_pkg(struct apk_database *db,
 		__hlist_del(dc, &pkg->owned_dirs.first);
 		apk_db_diri_free(db, diri);
 	}
-	apk_pkg_set_state(db, pkg, APK_STATE_NO_INSTALL);
+	apk_pkg_set_state(db, pkg, APK_PKG_NOT_INSTALLED);
 }
 
 int apk_db_install_pkg(struct apk_database *db,
@@ -1229,7 +1200,7 @@ int apk_db_install_pkg(struct apk_database *db,
 
 	bs->close(bs, csum, NULL);
 
-	apk_pkg_set_state(db, newpkg, APK_STATE_INSTALL);
+	apk_pkg_set_state(db, newpkg, APK_PKG_INSTALLED);
 
 	if (memcmp(csum, newpkg->csum, sizeof(csum)) != 0)
 		apk_warning("%s-%s: checksum does not match",