all: rework how arrays work

Instead of having a null pointer, use a dummy array which just
says the array is empty. This helps in multiple places of the code
which would otherwise need explicitly need to check first if the
array exists. This has been cause of multiple seg.faults in the
past as the array check is easily omitted.

This also removes (or fixes) all existing checks accordingly.

1 files changed, 26 insertions, 34 deletions

diff --git a/src/database.c b/src/database.c
index 46ad98c..2e886c2 100644
--- a/src/database.c
+++ b/src/database.c
@@ -64,10 +64,8 @@ static apk_blob_t pkg_name_get_key(apk_hash_item item)
 static void pkg_name_free(struct apk_name *name)
 {
 	free(name->name);
-	if (name->pkgs)
-		free(name->pkgs);
-	if (name->rdepends)
-		free(name->rdepends);
+	apk_package_array_free(&name->pkgs);
+	apk_name_array_free(&name->rdepends);
 	free(name);
 }
 
@@ -178,6 +176,8 @@ struct apk_name *apk_db_get_name(struct apk_database *db, apk_blob_t name)
 
 	pn->name = apk_blob_cstr(name);
 	pn->id = db->name_id++;
+	apk_package_array_init(&pn->pkgs);
+	apk_name_array_init(&pn->rdepends);
 	apk_hash_insert_hashed(&db->available.names, pn, hash);
 
 	return pn;
@@ -382,17 +382,13 @@ static void apk_db_pkg_rdepends(struct apk_database *db, struct apk_package *pkg
 {
 	int i, j;
 
-	if (pkg->depends == NULL)
-		return;
-
 	for (i = 0; i < pkg->depends->num; i++) {
 		struct apk_name *rname = pkg->depends->item[i].name;
 
-		if (rname->rdepends) {
-			for (j = 0; j < rname->rdepends->num; j++)
-				if (rname->rdepends->item[j] == pkg->name)
-					return;
-		}
+		for (j = 0; j < rname->rdepends->num; j++)
+			if (rname->rdepends->item[j] == pkg->name)
+				return;
+
 		*apk_name_array_add(&rname->rdepends) = pkg->name;
 	}
 }
@@ -859,7 +855,8 @@ static void apk_db_triggers_read(struct apk_database *db, struct apk_bstream *bs
 
 		ipkg = pkg->ipkg;
 		apk_blob_for_each_segment(l, " ", parse_triggers, ipkg);
-		if (ipkg->triggers && !list_hashed(&ipkg->trigger_pkgs_list))
+		if (ipkg->triggers->num != 0 &&
+		    !list_hashed(&ipkg->trigger_pkgs_list))
 			list_add_tail(&ipkg->trigger_pkgs_list,
 				      &db->installed.triggers);
 	}
@@ -887,7 +884,7 @@ static int apk_db_read_state(struct apk_database *db, int flags)
 		apk_deps_parse(db, &db->world, blob);
 		free(blob.ptr);
 
-		for (i = 0; db->world != NULL && i < db->world->num; i++)
+		for (i = 0; i < db->world->num; i++)
 			db->world->item[i].name->flags |= APK_NAME_TOPLEVEL;
 	}
 
@@ -1046,6 +1043,8 @@ int apk_db_open(struct apk_database *db, struct apk_db_options *dbopts)
 	apk_hash_init(&db->installed.files, &file_hash_ops, 10000);
 	list_init(&db->installed.packages);
 	list_init(&db->installed.triggers);
+	apk_dependency_array_init(&db->world);
+	apk_string_array_init(&db->protected_paths);
 	db->cache_dir = apk_static_cache_dir;
 	db->permanent = 1;
 
@@ -1262,13 +1261,10 @@ void apk_db_close(struct apk_database *db)
 	for (i = 0; i < db->num_repos; i++) {
 		free(db->repos[i].url);
 	}
-	if (db->protected_paths) {
-		for (i = 0; i < db->protected_paths->num; i++)
-			free(db->protected_paths->item[i]);
-		free(db->protected_paths);
-	}
-	if (db->world)
-		free(db->world);
+	for (i = 0; i < db->protected_paths->num; i++)
+		free(db->protected_paths->item[i]);
+	apk_dependency_array_free(&db->world);
+	apk_string_array_free(&db->protected_paths);
 
 	apk_hash_free(&db->available.packages);
 	apk_hash_free(&db->available.names);
@@ -1309,10 +1305,10 @@ static int fire_triggers(apk_hash_item item, void *ctx)
 				    FNM_PATHNAME) != 0)
 				continue;
 
-			if (ipkg->pending_triggers == NULL)
+			/* And place holder for script name */
+			if (ipkg->pending_triggers->num == 0)
 				*apk_string_array_add(&ipkg->pending_triggers) =
 					NULL;
-
 			*apk_string_array_add(&ipkg->pending_triggers) =
 				dbd->rooted_name;
 			break;
@@ -1329,14 +1325,13 @@ int apk_db_run_triggers(struct apk_database *db)
 	apk_hash_foreach(&db->installed.dirs, fire_triggers, db);
 
 	list_for_each_entry(ipkg, &db->installed.triggers, trigger_pkgs_list) {
-		if (ipkg->pending_triggers == NULL)
+		if (ipkg->pending_triggers->num == 0)
 			continue;
 
 		*apk_string_array_add(&ipkg->pending_triggers) = NULL;
 		apk_ipkg_run_script(ipkg, db->root_fd, APK_SCRIPT_TRIGGER,
 				    ipkg->pending_triggers->item);
-		free(ipkg->pending_triggers);
-		ipkg->pending_triggers = NULL;
+		apk_string_array_free(&ipkg->pending_triggers);
 	}
 
 	return 0;
@@ -1651,13 +1646,11 @@ static int read_info_line(void *_ctx, apk_blob_t line)
 	if (apk_blob_compare(APK_BLOB_STR("replaces"), l) == 0) {
 		apk_blob_for_each_segment(r, " ", parse_replaces, ctx);
 	} else if (apk_blob_compare(APK_BLOB_STR("triggers"), l) == 0) {
-		if (ipkg->triggers) {
-			free(ipkg->triggers);
-			ipkg->triggers = NULL;
-		}
+		apk_string_array_resize(&ipkg->triggers, 0);
 		apk_blob_for_each_segment(r, " ", parse_triggers, ctx->ipkg);
 
-		if (ctx->ipkg->triggers && !list_hashed(&ipkg->trigger_pkgs_list))
+		if (ctx->ipkg->triggers->num != 0 &&
+		    !list_hashed(&ipkg->trigger_pkgs_list))
 			list_add_tail(&ipkg->trigger_pkgs_list,
 				      &db->installed.triggers);
 	} else {
@@ -2118,10 +2111,9 @@ int apk_db_install_pkg(struct apk_database *db,
 	}
 
 	ipkg->flags |= APK_IPKGF_RUN_ALL_TRIGGERS;
-	if (ipkg->triggers) {
+	if (ipkg->triggers->num != 0) {
 		list_del(&ipkg->trigger_pkgs_list);
-		free(ipkg->triggers);
-		ipkg->triggers = NULL;
+		apk_string_array_free(&ipkg->triggers);
 	}
 
 	if (oldpkg != NULL && oldpkg != newpkg && oldpkg->ipkg != NULL) {