Add install_symlink soong module type

This can be used to install symlinks to arbitrary locations/targets
on the device. Used to replace a make-built symlink.

Bug: 205632228
Test: built and ran the emulator observed the /system/bin/hwservicemanager symlink is still there
Change-Id: I6df922c8d919e6d56fa79702815a89c98f4d65ed

etc/install_symlink_test.go

@@ -0,0 +1,135 @@
+// Copyright 2023 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package etc
+
+import (
+	"android/soong/android"
+	"strings"
+	"testing"
+)
+
+var prepareForInstallSymlinkTest = android.GroupFixturePreparers(
+	android.PrepareForTestWithArchMutator,
+	android.FixtureRegisterWithContext(RegisterInstallSymlinkBuildComponents),
+)
+
+func TestInstallSymlinkBasic(t *testing.T) {
+	result := prepareForInstallSymlinkTest.RunTestWithBp(t, `
+		install_symlink {
+			name: "foo",
+			installed_location: "bin/foo",
+			symlink_target: "/system/system_ext/bin/foo",
+		}
+	`)
+
+	foo_variants := result.ModuleVariantsForTests("foo")
+	if len(foo_variants) != 1 {
+		t.Fatalf("expected 1 variant, got %#v", foo_variants)
+	}
+
+	foo := result.ModuleForTests("foo", "android_common").Module()
+	androidMkEntries := android.AndroidMkEntriesForTest(t, result.TestContext, foo)
+	if len(androidMkEntries) != 1 {
+		t.Fatalf("expected 1 androidmkentry, got %d", len(androidMkEntries))
+	}
+
+	symlinks := androidMkEntries[0].EntryMap["LOCAL_SOONG_INSTALL_SYMLINKS"]
+	if len(symlinks) != 1 {
+		t.Fatalf("Expected 1 symlink, got %d", len(symlinks))
+	}
+
+	if !strings.HasSuffix(symlinks[0], "system/bin/foo") {
+		t.Fatalf("Expected symlink install path to end in system/bin/foo, got: %s", symlinks[0])
+	}
+}
+
+func TestInstallSymlinkToRecovery(t *testing.T) {
+	result := prepareForInstallSymlinkTest.RunTestWithBp(t, `
+		install_symlink {
+			name: "foo",
+			installed_location: "bin/foo",
+			symlink_target: "/system/system_ext/bin/foo",
+			recovery: true,
+		}
+	`)
+
+	foo_variants := result.ModuleVariantsForTests("foo")
+	if len(foo_variants) != 1 {
+		t.Fatalf("expected 1 variant, got %#v", foo_variants)
+	}
+
+	foo := result.ModuleForTests("foo", "android_common").Module()
+	androidMkEntries := android.AndroidMkEntriesForTest(t, result.TestContext, foo)
+	if len(androidMkEntries) != 1 {
+		t.Fatalf("expected 1 androidmkentry, got %d", len(androidMkEntries))
+	}
+
+	symlinks := androidMkEntries[0].EntryMap["LOCAL_SOONG_INSTALL_SYMLINKS"]
+	if len(symlinks) != 1 {
+		t.Fatalf("Expected 1 symlink, got %d", len(symlinks))
+	}
+
+	if !strings.HasSuffix(symlinks[0], "recovery/root/system/bin/foo") {
+		t.Fatalf("Expected symlink install path to end in recovery/root/system/bin/foo, got: %s", symlinks[0])
+	}
+}
+
+func TestErrorOnNonCleanTarget(t *testing.T) {
+	prepareForInstallSymlinkTest.
+		ExtendWithErrorHandler(android.FixtureExpectsOneErrorPattern("Should be a clean filepath")).
+		RunTestWithBp(t, `
+		install_symlink {
+			name: "foo",
+			installed_location: "bin/foo",
+			symlink_target: "/system/system_ext/../bin/foo",
+		}
+	`)
+}
+
+func TestErrorOnNonCleanInstalledLocation(t *testing.T) {
+	prepareForInstallSymlinkTest.
+		ExtendWithErrorHandler(android.FixtureExpectsOneErrorPattern("Should be a clean filepath")).
+		RunTestWithBp(t, `
+		install_symlink {
+			name: "foo",
+			installed_location: "bin/../foo",
+			symlink_target: "/system/system_ext/bin/foo",
+		}
+	`)
+}
+
+func TestErrorOnInstalledPathStartingWithDotDot(t *testing.T) {
+	prepareForInstallSymlinkTest.
+		ExtendWithErrorHandler(android.FixtureExpectsOneErrorPattern("Should not start with / or \\.\\./")).
+		RunTestWithBp(t, `
+		install_symlink {
+			name: "foo",
+			installed_location: "../bin/foo",
+			symlink_target: "/system/system_ext/bin/foo",
+		}
+	`)
+}
+
+func TestErrorOnInstalledPathStartingWithSlash(t *testing.T) {
+	prepareForInstallSymlinkTest.
+		ExtendWithErrorHandler(android.FixtureExpectsOneErrorPattern("Should not start with / or \\.\\./")).
+		RunTestWithBp(t, `
+		install_symlink {
+			name: "foo",
+			installed_location: "/bin/foo",
+			symlink_target: "/system/system_ext/bin/foo",
+		}
+	`)
+}