cmd/vendor/.../pprof: update to 0f7d9ba1

In particular, to pull a few fixes that were causing some tests to be
flaky on our build dashboard.

Fixes #24405.
Fixes #24508.
Fixes #24611.

Change-Id: I713156ad11c924e4a4b603144d10395523d526ed
Reviewed-on: https://go-review.googlesource.com/105275
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/cmd/vendor/github.com/google/pprof/driver/driver.go

@@ -41,6 +41,12 @@ func (o *Options) internalOptions() *plugin.Options {
 	if o.Sym != nil {
 		sym = &internalSymbolizer{o.Sym}
 	}
+	var httpServer func(args *plugin.HTTPServerArgs) error
+	if o.HTTPServer != nil {
+		httpServer = func(args *plugin.HTTPServerArgs) error {
+			return o.HTTPServer(((*HTTPServerArgs)(args)))
+		}
+	}
 	return &plugin.Options{
 		Writer:     o.Writer,
 		Flagset:    o.Flagset,
@@ -48,9 +54,14 @@ func (o *Options) internalOptions() *plugin.Options {
 		Sym:        sym,
 		Obj:        obj,
 		UI:         o.UI,
+		HTTPServer: httpServer,
 	}
 }
 
+// HTTPServerArgs contains arguments needed by an HTTP server that
+// is exporting a pprof web interface.
+type HTTPServerArgs plugin.HTTPServerArgs
+
 // Options groups all the optional plugins into pprof.
 type Options struct {
 	Writer     Writer
@@ -59,6 +70,7 @@ type Options struct {
 	Sym        Symbolizer
 	Obj        ObjTool
 	UI         UI
+	HTTPServer func(*HTTPServerArgs) error
 }
 
 // Writer provides a mechanism to write data under a certain name,
@@ -206,6 +218,9 @@ type UI interface {
 	// interactive terminal (as opposed to being redirected to a file).
 	IsTerminal() bool
 
+	// WantBrowser indicates whether browser should be opened with the -http option.
+	WantBrowser() bool
+
 	// SetAutoComplete instructs the UI to call complete(cmd) to obtain
 	// the auto-completion of cmd, if the UI supports auto-completion at all.
 	SetAutoComplete(complete func(string) string)

src/cmd/vendor/github.com/google/pprof/internal/binutils/addr2liner.go

@@ -41,9 +41,11 @@ type addr2Liner struct {
 	rw   lineReaderWriter
 	base uint64
 
-	// nm holds an NM based addr2Liner which can provide
-	// better full names compared to addr2line, which often drops
-	// namespaces etc. from the names it returns.
+	// nm holds an addr2Liner using nm tool. Certain versions of addr2line
+	// produce incomplete names due to
+	// https://sourceware.org/bugzilla/show_bug.cgi?id=17541. As a workaround,
+	// the names from nm are used when they look more complete. See addrInfo()
+	// code below for the exact heuristic.
 	nm *addr2LinerNM
 }
 
@@ -215,17 +217,22 @@ func (d *addr2Liner) addrInfo(addr uint64) ([]plugin.Frame, error) {
 		return nil, err
 	}
 
-	// Get better name from nm if possible.
+	// Certain versions of addr2line produce incomplete names due to
+	// https://sourceware.org/bugzilla/show_bug.cgi?id=17541. Attempt to replace
+	// the name with a better one from nm.
 	if len(stack) > 0 && d.nm != nil {
 		nm, err := d.nm.addrInfo(addr)
 		if err == nil && len(nm) > 0 {
-			// Last entry in frame list should match since
-			// it is non-inlined. As a simple heuristic,
-			// we only switch to the nm-based name if it
-			// is longer.
+			// Last entry in frame list should match since it is non-inlined. As a
+			// simple heuristic, we only switch to the nm-based name if it is longer
+			// by 2 or more characters. We consider nm names that are longer by 1
+			// character insignificant to avoid replacing foo with _foo on MacOS (for
+			// unknown reasons read2line produces the former and nm produces the
+			// latter on MacOS even though both tools are asked to produce mangled
+			// names).
 			nmName := nm[len(nm)-1].Func
 			a2lName := stack[len(stack)-1].Func
-			if len(nmName) > len(a2lName) {
+			if len(nmName) > len(a2lName)+1 {
 				stack[len(stack)-1].Func = nmName
 			}
 		}

src/cmd/vendor/github.com/google/pprof/internal/binutils/binutils.go

@@ -81,6 +81,26 @@ func (bu *Binutils) update(fn func(r *binrep)) {
 	bu.rep = r
 }
 
+// String returns string representation of the binutils state for debug logging.
+func (bu *Binutils) String() string {
+	r := bu.get()
+	var llvmSymbolizer, addr2line, nm, objdump string
+	if r.llvmSymbolizerFound {
+		llvmSymbolizer = r.llvmSymbolizer
+	}
+	if r.addr2lineFound {
+		addr2line = r.addr2line
+	}
+	if r.nmFound {
+		nm = r.nm
+	}
+	if r.objdumpFound {
+		objdump = r.objdump
+	}
+	return fmt.Sprintf("llvm-symbolizer=%q addr2line=%q nm=%q objdump=%q fast=%t",
+		llvmSymbolizer, addr2line, nm, objdump, r.fast)
+}
+
 // SetFastSymbolization sets a toggle that makes binutils use fast
 // symbolization (using nm), which is much faster than addr2line but
 // provides only symbol name information (no file/line).
@@ -111,6 +131,11 @@ func initTools(b *binrep, config string) {
 	defaultPath := paths[""]
 	b.llvmSymbolizer, b.llvmSymbolizerFound = findExe("llvm-symbolizer", append(paths["llvm-symbolizer"], defaultPath...))
 	b.addr2line, b.addr2lineFound = findExe("addr2line", append(paths["addr2line"], defaultPath...))
+	if !b.addr2lineFound {
+		// On MacOS, brew installs addr2line under gaddr2line name, so search for
+		// that if the tool is not found by its default name.
+		b.addr2line, b.addr2lineFound = findExe("gaddr2line", append(paths["addr2line"], defaultPath...))
+	}
 	b.nm, b.nmFound = findExe("nm", append(paths["nm"], defaultPath...))
 	b.objdump, b.objdumpFound = findExe("objdump", append(paths["objdump"], defaultPath...))
 }
@@ -306,9 +331,9 @@ func (f *fileNM) SourceLine(addr uint64) ([]plugin.Frame, error) {
 }
 
 // fileAddr2Line implements the binutils.ObjFile interface, using
-// 'addr2line' to map addresses to symbols (with file/line number
-// information). It can be slow for large binaries with debug
-// information.
+// llvm-symbolizer, if that's available, or addr2line to map addresses to
+// symbols (with file/line number information). It can be slow for large
+// binaries with debug information.
 type fileAddr2Line struct {
 	once sync.Once
 	file

src/cmd/vendor/github.com/google/pprof/internal/binutils/binutils_test.go

@@ -265,8 +265,6 @@ func TestObjFile(t *testing.T) {
 func TestMachoFiles(t *testing.T) {
 	skipUnlessDarwinAmd64(t)
 
-	t.Skip("Disabled because of issues with addr2line (see https://github.com/google/pprof/pull/313#issuecomment-364073010)")
-
 	// Load `file`, pretending it was mapped at `start`. Then get the symbol
 	// table. Check that it contains the symbol `sym` and that the address
 	// `addr` gives the `expected` stack trace.
@@ -291,7 +289,7 @@ func TestMachoFiles(t *testing.T) {
 		{"lib normal mapping", "lib_mac_64", 0, math.MaxUint64, 0,
 			0xfa0, "_bar",
 			[]plugin.Frame{
-				{Func: "bar", File: "/tmp/lib.c", Line: 6},
+				{Func: "bar", File: "/tmp/lib.c", Line: 5},
 			}},
 	} {
 		t.Run(tc.desc, func(t *testing.T) {
@@ -300,6 +298,13 @@ func TestMachoFiles(t *testing.T) {
 			if err != nil {
 				t.Fatalf("Open: unexpected error %v", err)
 			}
+			t.Logf("binutils: %v", bu)
+			if runtime.GOOS == "darwin" && !bu.rep.addr2lineFound && !bu.rep.llvmSymbolizerFound {
+				// On OSX user needs to install gaddr2line or llvm-symbolizer with
+				// Homebrew, skip the test when the environment doesn't have it
+				// installed.
+				t.Skip("couldn't find addr2line or gaddr2line")
+			}
 			defer f.Close()
 			syms, err := f.Symbols(nil, 0)
 			if err != nil {

src/cmd/vendor/github.com/google/pprof/internal/binutils/testdata/build_mac.sh

+#!/bin/bash -x
+
+# This is a script that generates the test MacOS executables in this directory.
+# It should be needed very rarely to run this script. It is mostly provided
+# as a future reference on how the original binary set was created.
+
+set -o errexit
+
+cat <<EOF >/tmp/hello.cc
+#include <stdio.h>
+
+int main() {
+  printf("Hello, world!\n");
+  return 0;
+}
+EOF
+
+cat <<EOF >/tmp/lib.c
+int foo() {
+  return 1;
+}
+
+int bar() {
+  return 2;
+}
+EOF
+
+cd $(dirname $0)
+rm -rf exe_mac_64* lib_mac_64*
+clang -g -o exe_mac_64 /tmp/hello.c
+clang -g -o lib_mac_64 -dynamiclib /tmp/lib.c

src/cmd/vendor/github.com/google/pprof/internal/binutils/testdata/exe_mac_64.dSYM/Contents/Info.plist

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+  <dict>
+    <key>CFBundleDevelopmentRegion</key>
+    <string>English</string>
+    <key>CFBundleIdentifier</key>
+    <string>com.apple.xcode.dsym.exe_mac_64</string>
+    <key>CFBundleInfoDictionaryVersion</key>
+    <string>6.0</string>
+    <key>CFBundlePackageType</key>
+    <string>dSYM</string>
+    <key>CFBundleSignature</key>
+    <string>????</string>
+    <key>CFBundleShortVersionString</key>
+    <string>1.0</string>
+    <key>CFBundleVersion</key>
+    <string>1</string>
+  </dict>
+</plist>

src/cmd/vendor/github.com/google/pprof/internal/binutils/testdata/lib_mac_64.dSYM/Contents/Info.plist

+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+  <dict>
+    <key>CFBundleDevelopmentRegion</key>
+    <string>English</string>
+    <key>CFBundleIdentifier</key>
+    <string>com.apple.xcode.dsym.lib_mac_64</string>
+    <key>CFBundleInfoDictionaryVersion</key>
+    <string>6.0</string>
+    <key>CFBundlePackageType</key>
+    <string>dSYM</string>
+    <key>CFBundleSignature</key>
+    <string>????</string>
+    <key>CFBundleShortVersionString</key>
+    <string>1.0</string>
+    <key>CFBundleVersion</key>
+    <string>1</string>
+  </dict>
+</plist>

src/cmd/vendor/github.com/google/pprof/internal/driver/driver.go

@@ -54,7 +54,7 @@ func PProf(eo *plugin.Options) error {
 	}
 
 	if src.HTTPHostport != "" {
-		return serveWebInterface(src.HTTPHostport, p, o, true)
+		return serveWebInterface(src.HTTPHostport, p, o)
 	}
 	return interactive(p, o)
 }
@@ -138,7 +138,7 @@ func generateReport(p *profile.Profile, cmd []string, vars variables, o *plugin.
 
 	// Output to specified file.
 	o.UI.PrintErr("Generating report in ", output)
-	out, err := os.Create(output)
+	out, err := o.Writer.Open(output)
 	if err != nil {
 		return err
 	}

src/cmd/vendor/github.com/google/pprof/internal/driver/driver_test.go

@@ -96,9 +96,12 @@ func TestParse(t *testing.T) {
 	baseVars := pprofVariables
 	defer func() { pprofVariables = baseVars }()
 	for _, tc := range testcase {
+		t.Run(tc.flags+":"+tc.source, func(t *testing.T) {
 			// Reset the pprof variables before processing
 			pprofVariables = baseVars.makeCopy()
 
+			testUI := &proftest.TestUI{T: t, AllowRx: "Generating report in|Ignoring local file|expression matched no samples|Interpreted .* as range, not regexp"}
+
 			f := baseFlags()
 			f.args = []string{tc.source}
 
@@ -126,9 +129,9 @@ func TestParse(t *testing.T) {
 			o1.Flagset = f
 			o1.Fetch = testFetcher{}
 			o1.Sym = testSymbolizer{}
+			o1.UI = testUI
 			if err := PProf(o1); err != nil {
-			t.Errorf("%s %q:  %v", tc.source, tc.flags, err)
-			continue
+				t.Fatalf("%s %q:  %v", tc.source, tc.flags, err)
 			}
 			// Reset the pprof variables after the proto invocation
 			pprofVariables = baseVars.makeCopy()
@@ -164,6 +167,7 @@ func TestParse(t *testing.T) {
 			o2.Flagset = f
 			o2.Sym = testSymbolizeDemangler{}
 			o2.Obj = new(mockObjTool)
+			o2.UI = testUI
 
 			if err := PProf(o2); err != nil {
 				t.Errorf("%s: %v", tc.source, err)
@@ -177,8 +181,7 @@ func TestParse(t *testing.T) {
 			solution = "testdata/" + solution
 			sbuf, err := ioutil.ReadFile(solution)
 			if err != nil {
-			t.Errorf("reading solution file %s: %v", solution, err)
-			continue
+				t.Fatalf("reading solution file %s: %v", solution, err)
 			}
 			if runtime.GOOS == "windows" {
 				sbuf = bytes.Replace(sbuf, []byte("testdata/"), []byte("testdata\\"), -1)
@@ -204,6 +207,7 @@ func TestParse(t *testing.T) {
 					}
 				}
 			}
+		})
 	}
 }
 

src/cmd/vendor/github.com/google/pprof/internal/driver/fetch.go

@@ -407,6 +407,7 @@ mapping:
 				if matches, err := filepath.Glob(filepath.Join(path, m.BuildID, "*")); err == nil {
 					fileNames = append(fileNames, matches...)
 				}
+				fileNames = append(fileNames, filepath.Join(path, m.File, m.BuildID)) // perf path format
 			}
 			if m.File != "" {
 				// Try both the basename and the full path, to support the same directory
@@ -534,7 +535,8 @@ func convertPerfData(perfPath string, ui plugin.UI) (*os.File, error) {
 		return nil, err
 	}
 	deferDeleteTempFile(profile.Name())
-	cmd := exec.Command("perf_to_profile", perfPath, profile.Name())
+	cmd := exec.Command("perf_to_profile", "-i", perfPath, "-o", profile.Name(), "-f")
+	cmd.Stdout, cmd.Stderr = os.Stdout, os.Stderr
 	if err := cmd.Run(); err != nil {
 		profile.Close()
 		return nil, fmt.Errorf("failed to convert perf.data file. Try github.com/google/perf_data_converter: %v", err)

src/cmd/vendor/github.com/google/pprof/internal/driver/fetch_test.go

@@ -283,8 +283,10 @@ func TestFetchWithBase(t *testing.T) {
 			}
 			f.args = tc.sources
 
-			o := setDefaults(nil)
-			o.Flagset = f
+			o := setDefaults(&plugin.Options{
+				UI:      &proftest.TestUI{T: t, AllowRx: "Local symbolization failed|Some binary filenames not available"},
+				Flagset: f,
+			})
 			src, _, err := parseFlags(o)
 
 			if err != nil {
@@ -397,18 +399,6 @@ func TestHttpsInsecure(t *testing.T) {
 	}()
 	defer l.Close()
 
-	go func() {
-		deadline := time.Now().Add(5 * time.Second)
-		for time.Now().Before(deadline) {
-			// Simulate a hotspot function. Spin in the inner loop for 100M iterations
-			// to ensure we get most of the samples landed here rather than in the
-			// library calls. We assume Go compiler won't elide the empty loop.
-			for i := 0; i < 1e8; i++ {
-			}
-			runtime.Gosched()
-		}
-	}()
-
 	outputTempFile, err := ioutil.TempFile("", "profile_output")
 	if err != nil {
 		t.Fatalf("Failed to create tempfile: %v", err)
@@ -416,7 +406,7 @@ func TestHttpsInsecure(t *testing.T) {
 	defer os.Remove(outputTempFile.Name())
 	defer outputTempFile.Close()
 
-	address := "https+insecure://" + l.Addr().String() + "/debug/pprof/profile"
+	address := "https+insecure://" + l.Addr().String() + "/debug/pprof/goroutine"
 	s := &source{
 		Sources:   []string{address},
 		Seconds:   10,
@@ -435,31 +425,14 @@ func TestHttpsInsecure(t *testing.T) {
 	if len(p.SampleType) == 0 {
 		t.Fatalf("fetchProfiles(%s) got empty profile: len(p.SampleType)==0", address)
 	}
-	switch runtime.GOOS {
-	case "plan9":
-		// CPU profiling is not supported on Plan9; see golang.org/issues/22564.
-		return
-	case "darwin":
-		if runtime.GOARCH == "arm" || runtime.GOARCH == "arm64" {
-			// CPU profiling on iOS os not symbolized; see golang.org/issues/22612.
-			return
-		}
-	}
 	if len(p.Function) == 0 {
 		t.Fatalf("fetchProfiles(%s) got non-symbolized profile: len(p.Function)==0", address)
 	}
-	if err := checkProfileHasFunction(p, "TestHttpsInsecure"); !badSigprofOS[runtime.GOOS] && err != nil {
+	if err := checkProfileHasFunction(p, "TestHttpsInsecure"); err != nil {
 		t.Fatalf("fetchProfiles(%s) %v", address, err)
 	}
 }
 
-// Some operating systems don't trigger the profiling signal right.
-// See https://github.com/golang/go/issues/13841.
-var badSigprofOS = map[string]bool{
-	"darwin": true,
-	"netbsd": true,
-}
-
 func checkProfileHasFunction(p *profile.Profile, fname string) error {
 	for _, f := range p.Function {
 		if strings.Contains(f.Name, fname) {

src/cmd/vendor/github.com/google/pprof/internal/driver/flamegraph.go

@@ -92,7 +92,7 @@ func (ui *webInterface) flamegraph(w http.ResponseWriter, req *http.Request) {
 		return
 	}
 
-	ui.render(w, "/flamegraph", "flamegraph", rpt, errList, config.Labels, webArgs{
+	ui.render(w, "flamegraph", rpt, errList, config.Labels, webArgs{
 		FlameGraph: template.JS(b),
 		Nodes:      nodeArr,
 	})

src/cmd/vendor/github.com/google/pprof/internal/driver/interactive.go

@@ -149,9 +149,14 @@ func greetings(p *profile.Profile, ui plugin.UI) {
 	numLabelUnits := identifyNumLabelUnits(p, ui)
 	ropt, err := reportOptions(p, numLabelUnits, pprofVariables)
 	if err == nil {
-		ui.Print(strings.Join(report.ProfileLabels(report.New(p, ropt)), "\n"))
+		rpt := report.New(p, ropt)
+		ui.Print(strings.Join(report.ProfileLabels(rpt), "\n"))
+		if rpt.Total() == 0 && len(p.SampleType) > 1 {
+			ui.Print(`No samples were found with the default sample value type.`)
+			ui.Print(`Try "sample_index" command to analyze different sample values.`, "\n")
 		}
-	ui.Print("Entering interactive mode (type \"help\" for commands, \"o\" for options)")
+	}
+	ui.Print(`Entering interactive mode (type "help" for commands, "o" for options)`)
 }
 
 // shortcuts represents composite commands that expand into a sequence

src/cmd/vendor/github.com/google/pprof/internal/driver/options.go

@@ -128,6 +128,10 @@ func (ui *stdUI) IsTerminal() bool {
 	return false
 }
 
+func (ui *stdUI) WantBrowser() bool {
+	return true
+}
+
 func (ui *stdUI) SetAutoComplete(func(string) string) {
 }
 

src/cmd/vendor/github.com/google/pprof/internal/driver/webhtml.go

@@ -233,7 +233,7 @@ table tr td {
 {{define "header"}}
 <div class="header">
   <div class="title">
-    <h1><a href="/">pprof</a></h1>
+    <h1><a href="./">pprof</a></h1>
   </div>
 
   <div id="view" class="menu-item">
@@ -242,12 +242,12 @@ table tr td {
       <i class="downArrow"></i>
     </div>
     <div class="submenu">
-      <a title="{{.Help.top}}"  href="/top" id="topbtn">Top</a>
-      <a title="{{.Help.graph}}" href="/" id="graphbtn">Graph</a>
-      <a title="{{.Help.flamegraph}}" href="/flamegraph" id="flamegraph">Flame Graph</a>
-      <a title="{{.Help.peek}}" href="/peek" id="peek">Peek</a>
-      <a title="{{.Help.list}}" href="/source" id="list">Source</a>
-      <a title="{{.Help.disasm}}" href="/disasm" id="disasm">Disassemble</a>
+      <a title="{{.Help.top}}"  href="./top" id="topbtn">Top</a>
+      <a title="{{.Help.graph}}" href="./" id="graphbtn">Graph</a>
+      <a title="{{.Help.flamegraph}}" href="./flamegraph" id="flamegraph">Flame Graph</a>
+      <a title="{{.Help.peek}}" href="./peek" id="peek">Peek</a>
+      <a title="{{.Help.list}}" href="./source" id="list">Source</a>
+      <a title="{{.Help.disasm}}" href="./disasm" id="disasm">Disassemble</a>
     </div>
   </div>
 
@@ -257,12 +257,12 @@ table tr td {
       <i class="downArrow"></i>
     </div>
     <div class="submenu">
-      <a title="{{.Help.focus}}" href="{{.BaseURL}}" id="focus">Focus</a>
-      <a title="{{.Help.ignore}}" href="{{.BaseURL}}" id="ignore">Ignore</a>
-      <a title="{{.Help.hide}}" href="{{.BaseURL}}" id="hide">Hide</a>
-      <a title="{{.Help.show}}" href="{{.BaseURL}}" id="show">Show</a>
+      <a title="{{.Help.focus}}" href="?" id="focus">Focus</a>
+      <a title="{{.Help.ignore}}" href="?" id="ignore">Ignore</a>
+      <a title="{{.Help.hide}}" href="?" id="hide">Hide</a>
+      <a title="{{.Help.show}}" href="?" id="show">Show</a>
       <hr>
-      <a title="{{.Help.reset}}" href="{{.BaseURL}}">Reset</a>
+      <a title="{{.Help.reset}}" href="?">Reset</a>
     </div>
   </div>
 
@@ -295,7 +295,7 @@ table tr td {
     {{.HTMLBody}}
   </div>
   {{template "script" .}}
-  <script>viewer({{.BaseURL}}, {{.Nodes}});</script>
+  <script>viewer(new URL(window.location.href), {{.Nodes}});</script>
 </body>
 </html>
 {{end}}
@@ -597,7 +597,7 @@ function viewer(baseUrl, nodes) {
   function handleKey(e) {
     if (e.keyCode != 13) return;
     window.location.href =
-        updateUrl(new URL({{.BaseURL}}, window.location.href), 'f');
+        updateUrl(new URL(window.location.href), 'f');
     e.preventDefault();
   }
 
@@ -963,7 +963,7 @@ function viewer(baseUrl, nodes) {
       bindSort('namehdr', 'Name');
     }
 
-    viewer({{.BaseURL}}, {{.Nodes}});
+    viewer(new URL(window.location.href), {{.Nodes}});
     makeTopTable({{.Total}}, {{.Top}});
   </script>
 </body>
@@ -986,7 +986,7 @@ function viewer(baseUrl, nodes) {
     {{.HTMLBody}}
   </div>
   {{template "script" .}}
-  <script>viewer({{.BaseURL}}, null);</script>
+  <script>viewer(new URL(window.location.href), null);</script>
 </body>
 </html>
 {{end}}
@@ -1007,7 +1007,7 @@ function viewer(baseUrl, nodes) {
     </pre>
   </div>
   {{template "script" .}}
-  <script>viewer({{.BaseURL}}, null);</script>
+  <script>viewer(new URL(window.location.href), null);</script>
 </body>
 </html>
 {{end}}
@@ -1044,7 +1044,7 @@ function viewer(baseUrl, nodes) {
     <div id="flamegraphdetails" class="flamegraph-details"></div>
   </div>
   {{template "script" .}}
-  <script>viewer({{.BaseURL}}, {{.Nodes}});</script>
+  <script>viewer(new URL(window.location.href), {{.Nodes}});</script>
   <script>{{template "d3script" .}}</script>
   <script>{{template "d3tipscript" .}}</script>
   <script>{{template "d3flamegraphscript" .}}</script>

src/cmd/vendor/github.com/google/pprof/internal/driver/webui.go

@@ -69,7 +69,6 @@ func (ec *errorCatcher) PrintErr(args ...interface{}) {
 
 // webArgs contains arguments passed to templates in webhtml.go.
 type webArgs struct {
-	BaseURL    string
 	Title      string
 	Errors     []string
 	Total      int64
@@ -82,7 +81,7 @@ type webArgs struct {
 	FlameGraph template.JS
 }
 
-func serveWebInterface(hostport string, p *profile.Profile, o *plugin.Options, wantBrowser bool) error {
+func serveWebInterface(hostport string, p *profile.Profile, o *plugin.Options) error {
 	host, port, err := getHostAndPort(hostport)
 	if err != nil {
 		return err
@@ -117,7 +116,7 @@ func serveWebInterface(hostport string, p *profile.Profile, o *plugin.Options, w
 		},
 	}
 
-	if wantBrowser {
+	if o.UI.WantBrowser() {
 		go openBrowser("http://"+args.Hostport, o)
 	}
 	return server(args)
@@ -172,7 +171,15 @@ func defaultWebServer(args *plugin.HTTPServerArgs) error {
 		}
 		h.ServeHTTP(w, req)
 	})
-	s := &http.Server{Handler: handler}
+
+	// We serve the ui at /ui/ and redirect there from the root. This is done
+	// to surface any problems with serving the ui at a non-root early. See:
+	//
+	// https://github.com/google/pprof/pull/348
+	mux := http.NewServeMux()
+	mux.Handle("/ui/", http.StripPrefix("/ui", handler))
+	mux.Handle("/", http.RedirectHandler("/ui/", http.StatusTemporaryRedirect))
+	s := &http.Server{Handler: mux}
 	return s.Serve(ln)
 }
 
@@ -248,11 +255,10 @@ func (ui *webInterface) makeReport(w http.ResponseWriter, req *http.Request,
 }
 
 // render generates html using the named template based on the contents of data.
-func (ui *webInterface) render(w http.ResponseWriter, baseURL, tmpl string,
+func (ui *webInterface) render(w http.ResponseWriter, tmpl string,
 	rpt *report.Report, errList, legend []string, data webArgs) {
 	file := getFromLegend(legend, "File: ", "unknown")
 	profile := getFromLegend(legend, "Type: ", "unknown")
-	data.BaseURL = baseURL
 	data.Title = file + " " + profile
 	data.Errors = errList
 	data.Total = rpt.Total()
@@ -297,7 +303,7 @@ func (ui *webInterface) dot(w http.ResponseWriter, req *http.Request) {
 		nodes = append(nodes, n.Info.Name)
 	}
 
-	ui.render(w, "/", "graph", rpt, errList, legend, webArgs{
+	ui.render(w, "graph", rpt, errList, legend, webArgs{
 		HTMLBody: template.HTML(string(svg)),
 		Nodes:    nodes,
 	})
@@ -332,7 +338,7 @@ func (ui *webInterface) top(w http.ResponseWriter, req *http.Request) {
 		nodes = append(nodes, item.Name)
 	}
 
-	ui.render(w, "/top", "top", rpt, errList, legend, webArgs{
+	ui.render(w, "top", rpt, errList, legend, webArgs{
 		Top:   top,
 		Nodes: nodes,
 	})
@@ -354,7 +360,7 @@ func (ui *webInterface) disasm(w http.ResponseWriter, req *http.Request) {
 	}
 
 	legend := report.ProfileLabels(rpt)
-	ui.render(w, "/disasm", "plaintext", rpt, errList, legend, webArgs{
+	ui.render(w, "plaintext", rpt, errList, legend, webArgs{
 		TextBody: out.String(),
 	})
 
@@ -378,7 +384,7 @@ func (ui *webInterface) source(w http.ResponseWriter, req *http.Request) {
 	}
 
 	legend := report.ProfileLabels(rpt)
-	ui.render(w, "/source", "sourcelisting", rpt, errList, legend, webArgs{
+	ui.render(w, "sourcelisting", rpt, errList, legend, webArgs{
 		HTMLBody: template.HTML(body.String()),
 	})
 }
@@ -399,7 +405,7 @@ func (ui *webInterface) peek(w http.ResponseWriter, req *http.Request) {
 	}
 
 	legend := report.ProfileLabels(rpt)
-	ui.render(w, "/peek", "plaintext", rpt, errList, legend, webArgs{
+	ui.render(w, "plaintext", rpt, errList, legend, webArgs{
 		TextBody: out.String(),
 	})
 }

src/cmd/vendor/github.com/google/pprof/internal/driver/webui_test.go

@@ -28,6 +28,7 @@ import (
 	"testing"
 
 	"github.com/google/pprof/internal/plugin"
+	"github.com/google/pprof/internal/proftest"
 	"github.com/google/pprof/profile"
 )
 
@@ -55,9 +56,9 @@ func TestWebInterface(t *testing.T) {
 	// Start server and wait for it to be initialized
 	go serveWebInterface("unused:1234", prof, &plugin.Options{
 		Obj:        fakeObjTool{},
-		UI:         &stdUI{},
+		UI:         &proftest.TestUI{},
 		HTTPServer: creator,
-	}, false)
+	})
 	<-serverCreated
 	defer server.Close()
 

src/cmd/vendor/github.com/google/pprof/internal/elfexec/elfexec.go

@@ -218,7 +218,7 @@ func GetBase(fh *elf.FileHeader, loadSegment *elf.ProgHeader, stextOffset *uint6
 			// So the base should be:
 			if stextOffset != nil && (start%pageSize) == (*stextOffset%pageSize) {
 				// perf uses the address of _stext as start. Some tools may
-				// adjust for this before calling GetBase, in which case the the page
+				// adjust for this before calling GetBase, in which case the page
 				// alignment should be different from that of stextOffset.
 				return start - *stextOffset, nil
 			}

src/cmd/vendor/github.com/google/pprof/internal/plugin/plugin.go

@@ -192,6 +192,9 @@ type UI interface {
 	// interactive terminal (as opposed to being redirected to a file).
 	IsTerminal() bool
 
+	// WantBrowser indicates whether a browser should be opened with the -http option.
+	WantBrowser() bool
+
 	// SetAutoComplete instructs the UI to call complete(cmd) to obtain
 	// the auto-completion of cmd, if the UI supports auto-completion at all.
 	SetAutoComplete(complete func(string) string)

src/cmd/vendor/github.com/google/pprof/internal/proftest/proftest.go

@@ -122,7 +122,7 @@ func (ui *TestUI) PrintErr(args ...interface{}) {
 	// implementation does. Without this Error() calls fmt.Sprintln() which
 	// _always_ adds spaces between arguments, unlike fmt.Sprint() which only
 	// adds them between arguments if neither is string.
-	ui.T.Error(fmt.Sprint(args...))
+	ui.T.Error("unexpected error: " + fmt.Sprint(args...))
 }
 
 // IsTerminal indicates if the UI is an interactive terminal.
@@ -130,6 +130,11 @@ func (ui *TestUI) IsTerminal() bool {
 	return false
 }
 
+// WantBrowser indicates whether a browser should be opened with the -http option.
+func (ui *TestUI) WantBrowser() bool {
+	return false
+}
+
 // SetAutoComplete is not supported by the test UI.
 func (ui *TestUI) SetAutoComplete(_ func(string) string) {
 }

src/cmd/vendor/github.com/google/pprof/internal/report/source.go

@@ -576,7 +576,7 @@ func openSourceFile(path, searchPath string) (*os.File, error) {
 	}
 
 	// Scan each component of the path
-	for _, dir := range strings.Split(searchPath, ":") {
+	for _, dir := range filepath.SplitList(searchPath) {
 		// Search up for every parent of each possible path.
 		for {
 			filename := filepath.Join(dir, path)

src/cmd/vendor/github.com/google/pprof/internal/report/source_test.go

@@ -2,6 +2,7 @@ package report
 
 import (
 	"bytes"
+	"io/ioutil"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -38,6 +39,85 @@ func TestWebList(t *testing.T) {
 	}
 }
 
+func TestOpenSourceFile(t *testing.T) {
+	tempdir, err := ioutil.TempDir("", "")
+	if err != nil {
+		t.Fatalf("failed to create temp dir: %v", err)
+	}
+	const lsep = string(filepath.ListSeparator)
+	for _, tc := range []struct {
+		desc       string
+		searchPath string
+		fs         []string
+		path       string
+		wantPath   string // If empty, error is wanted.
+	}{
+		{
+			desc:     "exact absolute path is found",
+			fs:       []string{"foo/bar.txt"},
+			path:     "$dir/foo/bar.txt",
+			wantPath: "$dir/foo/bar.txt",
+		},
+		{
+			desc:       "exact relative path is found",
+			searchPath: "$dir",
+			fs:         []string{"foo/bar.txt"},
+			path:       "foo/bar.txt",
+			wantPath:   "$dir/foo/bar.txt",
+		},
+		{
+			desc:       "multiple search path",
+			searchPath: "some/path" + lsep + "$dir",
+			fs:         []string{"foo/bar.txt"},
+			path:       "foo/bar.txt",
+			wantPath:   "$dir/foo/bar.txt",
+		},
+		{
+			desc:       "relative path is found in parent dir",
+			searchPath: "$dir/foo/bar",
+			fs:         []string{"bar.txt", "foo/bar/baz.txt"},
+			path:       "bar.txt",
+			wantPath:   "$dir/bar.txt",
+		},
+		{
+			desc: "error when not found",
+			path: "foo.txt",
+		},
+	} {
+		t.Run(tc.desc, func(t *testing.T) {
+			defer func() {
+				if err := os.RemoveAll(tempdir); err != nil {
+					t.Fatalf("failed to remove dir %q: %v", tempdir, err)
+				}
+			}()
+			for _, f := range tc.fs {
+				path := filepath.Join(tempdir, filepath.FromSlash(f))
+				dir := filepath.Dir(path)
+				if err := os.MkdirAll(dir, 0755); err != nil {
+					t.Fatalf("failed to create dir %q: %v", dir, err)
+				}
+				if err := ioutil.WriteFile(path, nil, 0644); err != nil {
+					t.Fatalf("failed to create file %q: %v", path, err)
+				}
+			}
+			tc.searchPath = filepath.FromSlash(strings.Replace(tc.searchPath, "$dir", tempdir, -1))
+			tc.path = filepath.FromSlash(strings.Replace(tc.path, "$dir", tempdir, 1))
+			tc.wantPath = filepath.FromSlash(strings.Replace(tc.wantPath, "$dir", tempdir, 1))
+			if file, err := openSourceFile(tc.path, tc.searchPath); err != nil && tc.wantPath != "" {
+				t.Errorf("openSourceFile(%q, %q) = err %v, want path %q", tc.path, tc.searchPath, err, tc.wantPath)
+			} else if err == nil {
+				defer file.Close()
+				gotPath := file.Name()
+				if tc.wantPath == "" {
+					t.Errorf("openSourceFile(%q, %q) = %q, want error", tc.path, tc.searchPath, gotPath)
+				} else if gotPath != tc.wantPath {
+					t.Errorf("openSourceFile(%q, %q) = %q, want path %q", tc.path, tc.searchPath, gotPath, tc.wantPath)
+				}
+			}
+		})
+	}
+}
+
 func TestIndentation(t *testing.T) {
 	for _, c := range []struct {
 		str        string

src/cmd/vendor/github.com/google/pprof/third_party/svgpan/svgpan.go

@@ -12,7 +12,7 @@ const JSSource = `
  * ======================
  *
  * Given an unique existing element with id "viewport" (or when missing, the
- * first g-element), including the the library into any SVG adds the following
+ * first g-element), including the library into any SVG adds the following
  * capabilities:
  *
  *  - Mouse panning