solver, pkg: implement versioned conflicts

One can now say in dependency "!foo<2" which means, that if foo is
installed, it needs to be >=2, but it's not a required dependency.

src/apk_package.h

@@ -59,7 +59,8 @@ struct apk_sign_ctx {
 struct apk_dependency {
 	struct apk_name *name;
 	apk_blob_t *version;
-	int result_mask;
+	unsigned optional : 1;
+	unsigned result_mask : 3;
 };
 APK_ARRAY(apk_dependency_array, struct apk_dependency);
 

src/apk_version.h

@@ -21,7 +21,6 @@
 #define APK_DEPMASK_REQUIRE	(APK_VERSION_EQUAL|APK_VERSION_LESS|\
 				 APK_VERSION_GREATER)
 #define APK_DEPMASK_CHECKSUM	(APK_VERSION_LESS|APK_VERSION_GREATER)
-#define APK_DEPMASK_CONFLICT	(0)
 
 const char *apk_version_op_string(int result_mask);
 int apk_version_result_mask(const char *str);

src/del.c

@@ -58,8 +58,7 @@ static void foreach_installed_reverse_dependency(
 			for (k = 0; k < pkg0->depends->num; k++) {
 				struct apk_dependency *dep = &pkg0->depends->item[k];
 				if (dep->name == name &&
-				    (dep->result_mask == APK_DEPMASK_CONFLICT ||
-				     apk_dep_is_satisfied(dep, pkg)))
+				    apk_dep_is_satisfied(dep, pkg))
 					break;
 			}
 			if (k >= pkg0->depends->num)

src/package.c

@@ -195,16 +195,16 @@ void apk_blob_pull_dep(apk_blob_t *b, struct apk_database *db, struct apk_depend
 {
 	struct apk_name *name;
 	apk_blob_t bname, bop, bver = APK_BLOB_NULL;
-	int mask = APK_DEPMASK_REQUIRE;
+	int mask = APK_DEPMASK_REQUIRE, optional = 0;
 	size_t len;
 
 	/* [!]name[<,<=,=,>=,>]ver */
 	if (APK_BLOB_IS_NULL(*b))
 		goto fail;
 	if (b->ptr[0] == '!') {
-		mask = 0;
 		b->ptr++;
 		b->len--;
+		optional = 1;
 	}
 	if (apk_blob_cspn(*b, "<>= ", &bname, &bop)) {
 		int i;
@@ -243,10 +243,14 @@ void apk_blob_pull_dep(apk_blob_t *b, struct apk_database *db, struct apk_depend
 	if (name == NULL)
 		goto fail;
 
+	if (optional)
+		mask ^= APK_DEPMASK_REQUIRE;
+
 	*dep = (struct apk_dependency){
 		.name = name,
 		.version = apk_blob_atomize_dup(bver),
 		.result_mask = mask,
+		.optional = optional,
 	};
 	return;
 fail:
@@ -292,11 +296,8 @@ static int parse_depend(void *ctx, apk_blob_t blob)
 
 int apk_dep_is_satisfied(struct apk_dependency *dep, struct apk_package *pkg)
 {
-	if (pkg == NULL) {
-		if (dep->result_mask == APK_DEPMASK_CONFLICT)
-			return 1;
-		return 0;
-	}
+	if (pkg == NULL)
+		return dep->optional;
 	if (dep->name != pkg->name)
 		return 0;
 	if (dep->result_mask == APK_DEPMASK_CHECKSUM) {
@@ -326,13 +327,16 @@ void apk_blob_pull_deps(apk_blob_t *b, struct apk_database *db, struct apk_depen
 
 void apk_blob_push_dep(apk_blob_t *to, struct apk_dependency *dep)
 {
-	if (dep->result_mask == APK_DEPMASK_CONFLICT)
+	int result_mask = dep->result_mask;
+
+	if (dep->optional) {
 		apk_blob_push_blob(to, APK_BLOB_PTR_LEN("!", 1));
+		result_mask ^= APK_DEPMASK_REQUIRE;
+	}
 
 	apk_blob_push_blob(to, APK_BLOB_STR(dep->name->name));
 
-	if (dep->result_mask != APK_DEPMASK_CONFLICT &&
-	    dep->result_mask != APK_DEPMASK_REQUIRE) {
+	if (!APK_BLOB_IS_NULL(*dep->version)) {
 		apk_blob_push_blob(to, APK_BLOB_STR(apk_version_op_string(dep->result_mask)));
 		apk_blob_push_blob(to, *dep->version);
 	}

src/solver.c

@@ -126,8 +126,7 @@ static void foreach_dependency_pkg(
 			struct apk_package *pkg0 = name0->pkgs->item[j];
 
 			/* conflict depends on all to be not installed */
-			if (dep->result_mask != APK_DEPMASK_CONFLICT &&
-			    !apk_dep_is_satisfied(dep, pkg0))
+			if (!apk_dep_is_satisfied(dep, pkg0))
 				continue;
 
 			cb(ss, pkg0);
@@ -154,8 +153,7 @@ static void foreach_rinstall_if_pkg(
 			for (k = 0; k < pkg0->install_if->num; k++) {
 				struct apk_dependency *dep = &pkg0->install_if->item[k];
 				if (dep->name == name &&
-				    (dep->result_mask == APK_DEPMASK_CONFLICT ||
-				     apk_dep_is_satisfied(dep, pkg)))
+				    apk_dep_is_satisfied(dep, pkg))
 					break;
 			}
 			if (k >= pkg0->install_if->num)
@@ -635,7 +633,7 @@ static void apply_constraint(struct apk_solver_state *ss, struct apk_dependency
 	if (ss->latest_decision != NULL)
 		inherit_name_state(name, ss->latest_decision->name);
 
-	if (dep->result_mask != APK_DEPMASK_CONFLICT)
+	if (!dep->optional)
 		ns->requirers++;
 	update_name_state(ss, name);
 }
@@ -675,7 +673,7 @@ static void undo_constraint(struct apk_solver_state *ss, struct apk_dependency *
 	if (ss->latest_decision && has_inherited_state(ss->latest_decision->name))
 		recalculate_inherted_name_state(name);
 
-	if (dep->result_mask != APK_DEPMASK_CONFLICT)
+	if (!dep->optional)
 		ns->requirers--;
 	update_name_state(ss, name);
 }

test/conflict.repo

+C:Q1EyN5AdpAOBJWKMR89pp/C66o+OE=
+P:a
+V:1
+S:1
+I:1
+D:!b<2
+
+C:Q1C4uoV7SdMdDhYg4OCVmI71D8HIA=
+P:b
+V:1
+S:1
+I:1
+
+C:Q1hdUpqRv5mYgJEqW52UmVsvmyysE=
+P:b
+V:2
+S:1
+I:1
+

test/conflict1.expect

+Installing b (2)
+Installing a (1)

test/conflict2.expect

+1 unsatisfiable dependencies (solution with 2 names)
+world: b<2