license metadata html notice files

Introduce the below command-line tool:

htmlnotice outputs a NOTICE.html file constructed from the license
texts of the transitive closure of dependencies.

Bug: 68860345
Bug: 151177513
Bug: 151953481
Bug: 213388645
Bug: 210912771

Test: m all
Test: m systemlicense
Test: m htmlnotice; out/soong/host/linux-x85/htmlnotice ...

where ... is the path to the .meta_lic file for the system image. In my
case if

$ export PRODUCT=$(realpath $ANDROID_PRODUCT_OUT --relative-to=$PWD)

... can be expressed as:

${PRODUCT}/gen/META/lic_intermediates/${PRODUCT}/system.img.meta_lic

Change-Id: Idbbeb2939d8cbf497237516fe468004fcd2d72a1
diff --git a/tools/compliance/Android.bp b/tools/compliance/Android.bp
index 5684f2f..0d7cf10 100644
--- a/tools/compliance/Android.bp
+++ b/tools/compliance/Android.bp
@@ -46,6 +46,13 @@
 }
 
 blueprint_go_binary {
+    name: "htmlnotice",
+    srcs: ["cmd/htmlnotice.go"],
+    deps: ["compliance-module"],
+    testSrcs: ["cmd/htmlnotice_test.go"],
+}
+
+blueprint_go_binary {
     name: "textnotice",
     srcs: ["cmd/textnotice.go"],
     deps: ["compliance-module"],
diff --git a/tools/compliance/cmd/htmlnotice.go b/tools/compliance/cmd/htmlnotice.go
new file mode 100644
index 0000000..cff1ff8
--- /dev/null
+++ b/tools/compliance/cmd/htmlnotice.go
@@ -0,0 +1,216 @@
+// Copyright 2021 Google LLC
+//
+// 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 main
+
+import (
+	"bytes"
+	"compliance"
+	"flag"
+	"fmt"
+	"html"
+	"io"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+var (
+	outputFile  = flag.String("o", "-", "Where to write the NOTICE text file. (default stdout)")
+	includeTOC  = flag.Bool("toc", true, "Whether to include a table of contents.")
+	stripPrefix = flag.String("strip_prefix", "", "Prefix to remove from paths. i.e. path to root")
+	title       = flag.String("title", "", "The title of the notice file.")
+
+	failNoneRequested = fmt.Errorf("\nNo license metadata files requested")
+	failNoLicenses    = fmt.Errorf("No licenses found")
+)
+
+type context struct {
+	stdout      io.Writer
+	stderr      io.Writer
+	rootFS      fs.FS
+	includeTOC  bool
+	stripPrefix string
+	title       string
+}
+
+func init() {
+	flag.Usage = func() {
+		fmt.Fprintf(os.Stderr, `Usage: %s {options} file.meta_lic {file.meta_lic...}
+
+Outputs an html NOTICE.html file.
+
+Options:
+`, filepath.Base(os.Args[0]))
+		flag.PrintDefaults()
+	}
+}
+
+func main() {
+	flag.Parse()
+
+	// Must specify at least one root target.
+	if flag.NArg() == 0 {
+		flag.Usage()
+		os.Exit(2)
+	}
+
+	if len(*outputFile) == 0 {
+		flag.Usage()
+		fmt.Fprintf(os.Stderr, "must specify file for -o; use - for stdout\n")
+		os.Exit(2)
+	} else {
+		dir, err := filepath.Abs(filepath.Dir(*outputFile))
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "cannot determine path to %q: %w\n", *outputFile, err)
+			os.Exit(1)
+		}
+		fi, err := os.Stat(dir)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "cannot read directory %q of %q: %w\n", dir, *outputFile, err)
+			os.Exit(1)
+		}
+		if !fi.IsDir() {
+			fmt.Fprintf(os.Stderr, "parent %q of %q is not a directory\n", dir, *outputFile)
+			os.Exit(1)
+		}
+	}
+
+	var ofile io.Writer
+	ofile = os.Stdout
+	if *outputFile != "-" {
+		ofile = &bytes.Buffer{}
+	}
+
+	ctx := &context{ofile, os.Stderr, os.DirFS("."), *includeTOC, *stripPrefix, *title}
+
+	err := htmlNotice(ctx, flag.Args()...)
+	if err != nil {
+		if err == failNoneRequested {
+			flag.Usage()
+		}
+		fmt.Fprintf(os.Stderr, "%s\n", err.Error())
+		os.Exit(1)
+	}
+	if *outputFile != "-" {
+		err := os.WriteFile(*outputFile, ofile.(*bytes.Buffer).Bytes(), 0666)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "could not write output to %q: %w\n", *outputFile, err)
+			os.Exit(1)
+		}
+	}
+	os.Exit(0)
+}
+
+// htmlNotice implements the htmlnotice utility.
+func htmlNotice(ctx *context, files ...string) error {
+	// Must be at least one root file.
+	if len(files) < 1 {
+		return failNoneRequested
+	}
+
+	// Read the license graph from the license metadata files (*.meta_lic).
+	licenseGraph, err := compliance.ReadLicenseGraph(ctx.rootFS, ctx.stderr, files)
+	if err != nil {
+		return fmt.Errorf("Unable to read license metadata file(s) %q: %v\n", files, err)
+	}
+	if licenseGraph == nil {
+		return failNoLicenses
+	}
+
+	// rs contains all notice resolutions.
+	rs := compliance.ResolveNotices(licenseGraph)
+
+	ni, err := compliance.IndexLicenseTexts(ctx.rootFS, licenseGraph, rs)
+	if err != nil {
+		return fmt.Errorf("Unable to read license text file(s) for %q: %v\n", files, err)
+	}
+
+	fmt.Fprintln(ctx.stdout, "<!DOCTYPE html>")
+	fmt.Fprintln(ctx.stdout, "<html><head>\n")
+	fmt.Fprintln(ctx.stdout, "<style type=\"text/css\">")
+	fmt.Fprintln(ctx.stdout, "body { padding: 2px; margin: 0; }")
+	fmt.Fprintln(ctx.stdout, "ul { list-style-type: none; margin: 0; padding: 0; }")
+	fmt.Fprintln(ctx.stdout, "li { padding-left: 1em; }")
+	fmt.Fprintln(ctx.stdout, ".file-list { margin-left: 1em; }")
+	fmt.Fprintln(ctx.stdout, "</style>\n")
+	if 0 < len(ctx.title) {
+		fmt.Fprintf(ctx.stdout, "<title>%s</title>\n", html.EscapeString(ctx.title))
+	}
+	fmt.Fprintln(ctx.stdout, "</head>")
+	fmt.Fprintln(ctx.stdout, "<body>")
+
+	if 0 < len(ctx.title) {
+		fmt.Fprintf(ctx.stdout, "  <h1>%s</h1>\n", html.EscapeString(ctx.title))
+	}
+	ids := make(map[string]string)
+	if ctx.includeTOC {
+		fmt.Fprintln(ctx.stdout, "  <ul class=\"toc\">")
+		i := 0
+		for installPath := range ni.InstallPaths() {
+			id := fmt.Sprintf("id%d", i)
+			i++
+			ids[installPath] = id
+			var p string
+			if 0 < len(ctx.stripPrefix) && strings.HasPrefix(installPath, ctx.stripPrefix) {
+				p = installPath[len(ctx.stripPrefix):]
+				if 0 == len(p) {
+					if 0 < len(ctx.title) {
+						p = ctx.title
+					} else {
+						p = "root"
+					}
+				}
+			} else {
+				p = installPath
+			}
+			fmt.Fprintf(ctx.stdout, "    <li id=\"%s\"><strong>%s</strong>\n      <ul>\n", id, html.EscapeString(p))
+			for _, h := range ni.InstallHashes(installPath) {
+				libs := ni.InstallHashLibs(installPath, h)
+				fmt.Fprintf(ctx.stdout, "        <li><a href=\"#%s\">%s</a>\n", h.String(), html.EscapeString(strings.Join(libs, ", ")))
+			}
+			fmt.Fprintln(ctx.stdout, "      </ul>")
+		}
+		fmt.Fprintln(ctx.stdout, "  </ul><!-- toc -->")
+	}
+	for h := range ni.Hashes() {
+		fmt.Fprintln(ctx.stdout, "  <hr>")
+		for _, libName := range ni.HashLibs(h) {
+			fmt.Fprintf(ctx.stdout, "  <strong>%s</strong> used by:\n    <ul class=\"file-list\">\n", html.EscapeString(libName))
+			for _, installPath := range ni.HashLibInstalls(h, libName) {
+				if id, ok := ids[installPath]; ok {
+					if 0 < len(ctx.stripPrefix) && strings.HasPrefix(installPath, ctx.stripPrefix) {
+						fmt.Fprintf(ctx.stdout, "      <li><a href=\"#%s\">%s</a>\n", id, html.EscapeString(installPath[len(ctx.stripPrefix):]))
+					} else {
+						fmt.Fprintf(ctx.stdout, "      <li><a href=\"#%s\">%s</a>\n", id, html.EscapeString(installPath))
+					}
+				} else {
+					if 0 < len(ctx.stripPrefix) && strings.HasPrefix(installPath, ctx.stripPrefix) {
+						fmt.Fprintf(ctx.stdout, "      <li>%s\n", html.EscapeString(installPath[len(ctx.stripPrefix):]))
+					} else {
+						fmt.Fprintf(ctx.stdout, "      <li>%s\n", html.EscapeString(installPath))
+					}
+				}
+			}
+			fmt.Fprintf(ctx.stdout, "    </ul>\n")
+		}
+		fmt.Fprintf(ctx.stdout, "  </ul>\n  <a id=\"%s\"/><pre class=\"license-text\">", h.String())
+		fmt.Fprintln(ctx.stdout, html.EscapeString(string(ni.HashText(h))))
+		fmt.Fprintln(ctx.stdout, "  </pre><!-- license-text -->")
+	}
+	fmt.Fprintln(ctx.stdout, "</body></html>")
+
+	return nil
+}
diff --git a/tools/compliance/cmd/htmlnotice_test.go b/tools/compliance/cmd/htmlnotice_test.go
new file mode 100644
index 0000000..8d3ea02
--- /dev/null
+++ b/tools/compliance/cmd/htmlnotice_test.go
@@ -0,0 +1,812 @@
+// Copyright 2021 Google LLC
+//
+// 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 main
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"html"
+	"os"
+	"regexp"
+	"strings"
+	"testing"
+)
+
+var (
+	horizontalRule = regexp.MustCompile(`^\s*<hr>\s*$`)
+	bodyTag        = regexp.MustCompile(`^\s*<body>\s*$`)
+	boilerPlate    = regexp.MustCompile(`^\s*(?:<ul class="file-list">|<ul>|</.*)\s*$`)
+	tocTag         = regexp.MustCompile(`^\s*<ul class="toc">\s*$`)
+	libraryName    = regexp.MustCompile(`^\s*<strong>(.*)</strong>\s\s*used\s\s*by\s*:\s*$`)
+	licenseText    = regexp.MustCompile(`^\s*<a id="[^"]{32}"/><pre class="license-text">(.*)$`)
+	titleTag       = regexp.MustCompile(`^\s*<title>(.*)</title>\s*$`)
+	h1Tag          = regexp.MustCompile(`^\s*<h1>(.*)</h1>\s*$`)
+	usedByTarget   = regexp.MustCompile(`^\s*<li>(?:<a href="#id[0-9]+">)?((?:out/(?:[^/<]*/)+)[^/<]*)(?:</a>)?\s*$`)
+	installTarget  = regexp.MustCompile(`^\s*<li id="id[0-9]+"><strong>(.*)</strong>\s*$`)
+	libReference   = regexp.MustCompile(`^\s*<li><a href="#[^"]{32}">(.*)</a>\s*$`)
+)
+
+func Test(t *testing.T) {
+	tests := []struct {
+		condition   string
+		name        string
+		roots       []string
+		includeTOC  bool
+		stripPrefix string
+		title       string
+		expectedOut []matcher
+	}{
+		{
+			condition: "firstparty",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/liba.so"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition:  "firstparty",
+			name:       "apex+toc",
+			roots:      []string{"highest.apex.meta_lic"},
+			includeTOC: true,
+			expectedOut: []matcher{
+				toc{},
+				target{"highest.apex"},
+				uses{"Android"},
+				target{"highest.apex/bin/bin1"},
+				uses{"Android"},
+				target{"highest.apex/bin/bin2"},
+				uses{"Android"},
+				target{"highest.apex/lib/liba.so"},
+				uses{"Android"},
+				target{"highest.apex/lib/libb.so"},
+				uses{"Android"},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/liba.so"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "apex-with-title",
+			roots:     []string{"highest.apex.meta_lic"},
+			title:     "Emperor",
+			expectedOut: []matcher{
+				pageTitle{"Emperor"},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/liba.so"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition:  "firstparty",
+			name:       "apex-with-title+toc",
+			roots:      []string{"highest.apex.meta_lic"},
+			includeTOC: true,
+			title:      "Emperor",
+			expectedOut: []matcher{
+				pageTitle{"Emperor"},
+				toc{},
+				target{"highest.apex"},
+				uses{"Android"},
+				target{"highest.apex/bin/bin1"},
+				uses{"Android"},
+				target{"highest.apex/bin/bin2"},
+				uses{"Android"},
+				target{"highest.apex/lib/liba.so"},
+				uses{"Android"},
+				target{"highest.apex/lib/libb.so"},
+				uses{"Android"},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/liba.so"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/liba.so"},
+				usedBy{"container.zip/libb.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "firstparty",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"lib/libd.so"},
+				firstParty{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/lib/liba.so"},
+				library{"External"},
+				usedBy{"highest.apex/bin/bin1"},
+				notice{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/libb.so"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/liba.so"},
+				library{"External"},
+				usedBy{"container.zip/bin1"},
+				notice{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"application"},
+				notice{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"bin/bin1"},
+				library{"External"},
+				usedBy{"bin/bin1"},
+				notice{},
+			},
+		},
+		{
+			condition: "notice",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"External"},
+				usedBy{"lib/libd.so"},
+				notice{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/libb.so"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/lib/liba.so"},
+				library{"External"},
+				usedBy{"highest.apex/bin/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/libb.so"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/liba.so"},
+				library{"External"},
+				usedBy{"container.zip/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"application"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"bin/bin1"},
+				library{"External"},
+				usedBy{"bin/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "reciprocal",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"External"},
+				usedBy{"lib/libd.so"},
+				notice{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/bin/bin2"},
+				firstParty{},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/libb.so"},
+				library{"Device"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/lib/liba.so"},
+				restricted{},
+				hr{},
+				library{"External"},
+				usedBy{"highest.apex/bin/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/bin2"},
+				firstParty{},
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/libb.so"},
+				library{"Device"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/liba.so"},
+				restricted{},
+				hr{},
+				library{"External"},
+				usedBy{"container.zip/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"application"},
+				restricted{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"bin/bin1"},
+				restricted{},
+				hr{},
+				library{"External"},
+				usedBy{"bin/bin1"},
+				reciprocal{},
+			},
+		},
+		{
+			condition: "restricted",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"External"},
+				usedBy{"lib/libd.so"},
+				notice{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "apex",
+			roots:     []string{"highest.apex.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex/bin/bin2"},
+				usedBy{"highest.apex/lib/libb.so"},
+				restricted{},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex"},
+				usedBy{"highest.apex/bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Android"},
+				usedBy{"highest.apex/bin/bin2"},
+				library{"Device"},
+				usedBy{"highest.apex/bin/bin1"},
+				usedBy{"highest.apex/lib/liba.so"},
+				library{"External"},
+				usedBy{"highest.apex/bin/bin1"},
+				proprietary{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "container",
+			roots:     []string{"container.zip.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip/bin2"},
+				usedBy{"container.zip/libb.so"},
+				restricted{},
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip"},
+				usedBy{"container.zip/bin1"},
+				firstParty{},
+				hr{},
+				library{"Android"},
+				usedBy{"container.zip/bin2"},
+				library{"Device"},
+				usedBy{"container.zip/bin1"},
+				usedBy{"container.zip/liba.so"},
+				library{"External"},
+				usedBy{"container.zip/bin1"},
+				proprietary{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "application",
+			roots:     []string{"application.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"application"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"application"},
+				proprietary{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "binary",
+			roots:     []string{"bin/bin1.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"Android"},
+				usedBy{"bin/bin1"},
+				firstParty{},
+				hr{},
+				library{"Device"},
+				usedBy{"bin/bin1"},
+				library{"External"},
+				usedBy{"bin/bin1"},
+				proprietary{},
+			},
+		},
+		{
+			condition: "proprietary",
+			name:      "library",
+			roots:     []string{"lib/libd.so.meta_lic"},
+			expectedOut: []matcher{
+				hr{},
+				library{"External"},
+				usedBy{"lib/libd.so"},
+				notice{},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.condition+" "+tt.name, func(t *testing.T) {
+			stdout := &bytes.Buffer{}
+			stderr := &bytes.Buffer{}
+
+			rootFiles := make([]string, 0, len(tt.roots))
+			for _, r := range tt.roots {
+				rootFiles = append(rootFiles, "testdata/"+tt.condition+"/"+r)
+			}
+
+			ctx := context{stdout, stderr, os.DirFS("."), tt.includeTOC, tt.stripPrefix, tt.title}
+
+			err := htmlNotice(&ctx, rootFiles...)
+			if err != nil {
+				t.Fatalf("htmlnotice: error = %w, stderr = %v", err, stderr)
+				return
+			}
+			if stderr.Len() > 0 {
+				t.Errorf("htmlnotice: gotStderr = %v, want none", stderr)
+			}
+
+			t.Logf("got stdout: %s", stdout.String())
+
+			t.Logf("want stdout: %s", matcherList(tt.expectedOut).String())
+
+			out := bufio.NewScanner(stdout)
+			lineno := 0
+			inBody := false
+			hasTitle := false
+			ttle, expectTitle := tt.expectedOut[0].(pageTitle)
+			for out.Scan() {
+				line := out.Text()
+				if strings.TrimLeft(line, " ") == "" {
+					continue
+				}
+				if !inBody {
+					if expectTitle {
+						if tl := checkTitle(line); 0 < len(tl) {
+							if tl != ttle.t {
+								t.Errorf("htmlnotice: unexpected title: got %q, want %q", tl, ttle.t)
+							}
+							hasTitle = true
+						}
+					}
+					if bodyTag.MatchString(line) {
+						inBody = true
+						if expectTitle && !hasTitle {
+							t.Errorf("htmlnotice: missing title: got no <title> tag, want <title>%s</title>", ttle.t)
+						}
+					}
+					continue
+				}
+				if boilerPlate.MatchString(line) {
+					continue
+				}
+				if len(tt.expectedOut) <= lineno {
+					t.Errorf("htmlnotice: unexpected output at line %d: got %q, want nothing (wanted %d lines)", lineno+1, line, len(tt.expectedOut))
+				} else if !tt.expectedOut[lineno].isMatch(line) {
+					t.Errorf("htmlnotice: unexpected output at line %d: got %q, want %q", lineno+1, line, tt.expectedOut[lineno].String())
+				}
+				lineno++
+			}
+			if !inBody {
+				t.Errorf("htmlnotice: missing body: got no <body> tag, want <body> tag followed by %s", matcherList(tt.expectedOut).String())
+				return
+			}
+			for ; lineno < len(tt.expectedOut); lineno++ {
+				t.Errorf("htmlnotice: missing output line %d: ended early, want %q", lineno+1, tt.expectedOut[lineno].String())
+			}
+		})
+	}
+}
+
+func checkTitle(line string) string {
+	groups := titleTag.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return ""
+	}
+	return groups[1]
+}
+
+type matcher interface {
+	isMatch(line string) bool
+	String() string
+}
+
+type pageTitle struct {
+	t string
+}
+
+func (m pageTitle) isMatch(line string) bool {
+	groups := h1Tag.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return groups[1] == html.EscapeString(m.t)
+}
+
+func (m pageTitle) String() string {
+	return "  <h1>" + html.EscapeString(m.t) + "</h1>"
+}
+
+type toc struct{}
+
+func (m toc) isMatch(line string) bool {
+	return tocTag.MatchString(line)
+}
+
+func (m toc) String() string {
+	return `  <ul class="toc">`
+}
+
+type target struct {
+	name string
+}
+
+func (m target) isMatch(line string) bool {
+	groups := installTarget.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return strings.HasPrefix(groups[1], "out/") && strings.HasSuffix(groups[1], "/"+html.EscapeString(m.name))
+}
+
+func (m target) String() string {
+	return `  <li id="id#"><strong>` + html.EscapeString(m.name) + `</strong>`
+}
+
+type uses struct {
+	name string
+}
+
+func (m uses) isMatch(line string) bool {
+	groups := libReference.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return groups[1] == html.EscapeString(m.name)
+}
+
+func (m uses) String() string {
+	return `  <li><a href="#hash">` + html.EscapeString(m.name) + `</a>`
+}
+
+type hr struct{}
+
+func (m hr) isMatch(line string) bool {
+	return horizontalRule.MatchString(line)
+}
+
+func (m hr) String() string {
+	return "  <hr>"
+}
+
+type library struct {
+	name string
+}
+
+func (m library) isMatch(line string) bool {
+	groups := libraryName.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return groups[1] == html.EscapeString(m.name)
+}
+
+func (m library) String() string {
+	return "  <strong>" + html.EscapeString(m.name) + "</strong> used by:"
+}
+
+type usedBy struct {
+	name string
+}
+
+func (m usedBy) isMatch(line string) bool {
+	groups := usedByTarget.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return strings.HasPrefix(groups[1], "out/") && strings.HasSuffix(groups[1], "/"+html.EscapeString(m.name))
+}
+
+func (m usedBy) String() string {
+	return "  <li>out/.../" + html.EscapeString(m.name)
+}
+
+func matchesText(line, text string) bool {
+	groups := licenseText.FindStringSubmatch(line)
+	if len(groups) != 2 {
+		return false
+	}
+	return groups[1] == html.EscapeString(text)
+}
+
+func expectedText(text string) string {
+	return `  <a href="#hash"/><pre class="license-text">` + html.EscapeString(text)
+}
+
+type firstParty struct{}
+
+func (m firstParty) isMatch(line string) bool {
+	return matchesText(line, "&&&First Party License&&&")
+}
+
+func (m firstParty) String() string {
+	return expectedText("&&&First Party License&&&")
+}
+
+type notice struct{}
+
+func (m notice) isMatch(line string) bool {
+	return matchesText(line, "%%%Notice License%%%")
+}
+
+func (m notice) String() string {
+	return expectedText("%%%Notice License%%%")
+}
+
+type reciprocal struct{}
+
+func (m reciprocal) isMatch(line string) bool {
+	return matchesText(line, "$$$Reciprocal License$$$")
+}
+
+func (m reciprocal) String() string {
+	return expectedText("$$$Reciprocal License$$$")
+}
+
+type restricted struct{}
+
+func (m restricted) isMatch(line string) bool {
+	return matchesText(line, "###Restricted License###")
+}
+
+func (m restricted) String() string {
+	return expectedText("###Restricted License###")
+}
+
+type proprietary struct{}
+
+func (m proprietary) isMatch(line string) bool {
+	return matchesText(line, "@@@Proprietary License@@@")
+}
+
+func (m proprietary) String() string {
+	return expectedText("@@@Proprietary License@@@")
+}
+
+type matcherList []matcher
+
+func (l matcherList) String() string {
+	var sb strings.Builder
+	for _, m := range l {
+		s := m.String()
+		if s[:3] == s[len(s)-3:] {
+			fmt.Fprintln(&sb)
+		}
+		fmt.Fprintf(&sb, "%s\n", s)
+		if s[:3] == s[len(s)-3:] {
+			fmt.Fprintln(&sb)
+		}
+	}
+	return sb.String()
+}
diff --git a/tools/compliance/noticeindex.go b/tools/compliance/noticeindex.go
index 06c2627..5b7f376 100644
--- a/tools/compliance/noticeindex.go
+++ b/tools/compliance/noticeindex.go
@@ -54,8 +54,8 @@
 	text map[hash][]byte
 	// hashLibInstall maps hashes to libraries to install paths.
 	hashLibInstall map[hash]map[string]map[string]struct{}
-	// installLibHash maps install paths to libraries to hashes.
-	installLibHash map[string]map[string]map[hash]struct{}
+	// installHashLib maps install paths to libraries to hashes.
+	installHashLib map[string]map[hash]map[string]struct{}
 	// libHash maps libraries to hashes.
 	libHash map[string]map[hash]struct{}
 	// targetHash maps target nodes to hashes.
@@ -75,7 +75,7 @@
 		make(map[string]hash),
 		make(map[hash][]byte),
 		make(map[hash]map[string]map[string]struct{}),
-		make(map[string]map[string]map[hash]struct{}),
+		make(map[string]map[hash]map[string]struct{}),
 		make(map[string]map[hash]struct{}),
 		make(map[*TargetNode]map[hash]struct{}),
 		make(map[string]string),
@@ -115,15 +115,15 @@
 				ni.libHash[libName][h] = struct{}{}
 			}
 			for _, installPath := range installPaths {
-				if _, ok := ni.installLibHash[installPath]; !ok {
-					ni.installLibHash[installPath] = make(map[string]map[hash]struct{})
-					ni.installLibHash[installPath][libName] = make(map[hash]struct{})
-					ni.installLibHash[installPath][libName][h] = struct{}{}
-				} else if _, ok = ni.installLibHash[installPath][libName]; !ok {
-					ni.installLibHash[installPath][libName] = make(map[hash]struct{})
-					ni.installLibHash[installPath][libName][h] = struct{}{}
-				} else if _, ok = ni.installLibHash[installPath][libName][h]; !ok {
-					ni.installLibHash[installPath][libName][h] = struct{}{}
+				if _, ok := ni.installHashLib[installPath]; !ok {
+					ni.installHashLib[installPath] = make(map[hash]map[string]struct{})
+					ni.installHashLib[installPath][h] = make(map[string]struct{})
+					ni.installHashLib[installPath][h][libName] = struct{}{}
+				} else if _, ok = ni.installHashLib[installPath][h]; !ok {
+					ni.installHashLib[installPath][h] = make(map[string]struct{})
+					ni.installHashLib[installPath][h][libName] = struct{}{}
+				} else if _, ok = ni.installHashLib[installPath][h][libName]; !ok {
+					ni.installHashLib[installPath][h][libName] = struct{}{}
 				}
 				if _, ok := ni.hashLibInstall[h]; !ok {
 					ni.hashLibInstall[h] = make(map[string]map[string]struct{})
@@ -197,7 +197,7 @@
 				hl = append(hl, h)
 			}
 			if len(hl) > 0 {
-				sort.Sort(hashList{ni, libName, &hl})
+				sort.Sort(hashList{ni, libName, "", &hl})
 				for _, h := range hl {
 					c <- h
 				}
@@ -230,6 +230,46 @@
 	return installs
 }
 
+// InstallPaths returns the ordered channel of indexed install paths.
+func (ni *NoticeIndex) InstallPaths() chan string {
+	c := make(chan string)
+	go func() {
+		paths := make([]string, 0, len(ni.installHashLib))
+		for path := range ni.installHashLib {
+			paths = append(paths, path)
+		}
+		sort.Strings(paths)
+		for _, installPath := range paths {
+			c <- installPath
+		}
+		close(c)
+	}()
+	return c
+}
+
+// InstallHashes returns the ordered array of hashes attached to `installPath`.
+func (ni *NoticeIndex) InstallHashes(installPath string) []hash {
+	result := make([]hash, 0, len(ni.installHashLib[installPath]))
+	for h := range ni.installHashLib[installPath] {
+		result = append(result, h)
+	}
+	if len(result) > 0 {
+		sort.Sort(hashList{ni, "", installPath, &result})
+	}
+	return result
+}
+
+// InstallHashLibs returns the ordered array of library names attached to
+// `installPath` as hash `h`.
+func (ni *NoticeIndex) InstallHashLibs(installPath string, h hash) []string {
+	result := make([]string, 0, len(ni.installHashLib[installPath][h]))
+	for libName := range ni.installHashLib[installPath][h] {
+		result = append(result, libName)
+	}
+	sort.Strings(result)
+	return result
+}
+
 // HashText returns the file content of the license text hashed as `h`.
 func (ni *NoticeIndex) HashText(h hash) []byte {
 	return ni.text[h]
@@ -492,9 +532,10 @@
 
 // hashList orders an array of hashes
 type hashList struct {
-	ni      *NoticeIndex
-	libName string
-	hashes  *[]hash
+	ni          *NoticeIndex
+	libName     string
+	installPath string
+	hashes      *[]hash
 }
 
 // Len returns the count of elements in the slice.
@@ -511,6 +552,14 @@
 	if 0 < len(l.libName) {
 		insti = len(l.ni.hashLibInstall[(*l.hashes)[i]][l.libName])
 		instj = len(l.ni.hashLibInstall[(*l.hashes)[j]][l.libName])
+	} else {
+		libsi := l.ni.InstallHashLibs(l.installPath, (*l.hashes)[i])
+		libsj := l.ni.InstallHashLibs(l.installPath, (*l.hashes)[j])
+		libsis := strings.Join(libsi, " ")
+		libsjs := strings.Join(libsj, " ")
+		if libsis != libsjs {
+			return libsis < libsjs
+		}
 	}
 	if insti == instj {
 		leni := len(l.ni.text[(*l.hashes)[i]])