1// Copyright 2017 Google Inc. All Rights Reserved.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package driver
16
17import (
18	"embed"
19	"fmt"
20	"html/template"
21	"os"
22	"sync"
23
24	"github.com/google/pprof/internal/report"
25)
26
27var (
28	htmlTemplates    *template.Template // Lazily loaded templates
29	htmlTemplateInit sync.Once
30)
31
32// getHTMLTemplates returns the set of HTML templates used by pprof,
33// initializing them if necessary.
34func getHTMLTemplates() *template.Template {
35	htmlTemplateInit.Do(func() {
36		htmlTemplates = template.New("templategroup")
37		addTemplates(htmlTemplates)
38		report.AddSourceTemplates(htmlTemplates)
39	})
40	return htmlTemplates
41}
42
43//go:embed html
44var embeddedFiles embed.FS
45
46// addTemplates adds a set of template definitions to templates.
47func addTemplates(templates *template.Template) {
48	// Load specified file.
49	loadFile := func(fname string) string {
50		data, err := embeddedFiles.ReadFile(fname)
51		if err != nil {
52			fmt.Fprintf(os.Stderr, "internal/driver: embedded file %q not found\n",
53				fname)
54			os.Exit(1)
55		}
56		return string(data)
57	}
58	loadCSS := func(fname string) string {
59		return `<style type="text/css">` + "\n" + loadFile(fname) + `</style>` + "\n"
60	}
61	loadJS := func(fname string) string {
62		return `<script>` + "\n" + loadFile(fname) + `</script>` + "\n"
63	}
64
65	// Define a named template with specified contents.
66	def := func(name, contents string) {
67		sub := template.New(name)
68		template.Must(sub.Parse(contents))
69		template.Must(templates.AddParseTree(name, sub.Tree))
70	}
71
72	// Embedded files.
73	def("css", loadCSS("html/common.css"))
74	def("header", loadFile("html/header.html"))
75	def("graph", loadFile("html/graph.html"))
76	def("graph_css", loadCSS("html/graph.css"))
77	def("script", loadJS("html/common.js"))
78	def("top", loadFile("html/top.html"))
79	def("sourcelisting", loadFile("html/source.html"))
80	def("plaintext", loadFile("html/plaintext.html"))
81	// TODO: Rename "stacks" to "flamegraph" to seal moving off d3 flamegraph.
82	def("stacks", loadFile("html/stacks.html"))
83	def("stacks_css", loadCSS("html/stacks.css"))
84	def("stacks_js", loadJS("html/stacks.js"))
85}
86