Bump google.golang.org/api

vendor/github.com/google/pprof/internal/binutils/addr2liner_nm.go

@@ -0,0 +1,124 @@
+// Copyright 2014 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 binutils
+
+import (
+	"bufio"
+	"bytes"
+	"io"
+	"os/exec"
+	"strconv"
+	"strings"
+
+	"github.com/google/pprof/internal/plugin"
+)
+
+const (
+	defaultNM = "nm"
+)
+
+// addr2LinerNM is a connection to an nm command for obtaining address
+// information from a binary.
+type addr2LinerNM struct {
+	m []symbolInfo // Sorted list of addresses from binary.
+}
+
+type symbolInfo struct {
+	address uint64
+	name    string
+}
+
+//  newAddr2LinerNM starts the given nm command reporting information about the
+// given executable file. If file is a shared library, base should be
+// the address at which it was mapped in the program under
+// consideration.
+func newAddr2LinerNM(cmd, file string, base uint64) (*addr2LinerNM, error) {
+	if cmd == "" {
+		cmd = defaultNM
+	}
+	var b bytes.Buffer
+	c := exec.Command(cmd, "-n", file)
+	c.Stdout = &b
+	if err := c.Run(); err != nil {
+		return nil, err
+	}
+	return parseAddr2LinerNM(base, &b)
+}
+
+func parseAddr2LinerNM(base uint64, nm io.Reader) (*addr2LinerNM, error) {
+	a := &addr2LinerNM{
+		m: []symbolInfo{},
+	}
+
+	// Parse nm output and populate symbol map.
+	// Skip lines we fail to parse.
+	buf := bufio.NewReader(nm)
+	for {
+		line, err := buf.ReadString('\n')
+		if line == "" && err != nil {
+			if err == io.EOF {
+				break
+			}
+			return nil, err
+		}
+		line = strings.TrimSpace(line)
+		fields := strings.SplitN(line, " ", 3)
+		if len(fields) != 3 {
+			continue
+		}
+		address, err := strconv.ParseUint(fields[0], 16, 64)
+		if err != nil {
+			continue
+		}
+		a.m = append(a.m, symbolInfo{
+			address: address + base,
+			name:    fields[2],
+		})
+	}
+
+	return a, nil
+}
+
+// addrInfo returns the stack frame information for a specific program
+// address. It returns nil if the address could not be identified.
+func (a *addr2LinerNM) addrInfo(addr uint64) ([]plugin.Frame, error) {
+	if len(a.m) == 0 || addr < a.m[0].address || addr > a.m[len(a.m)-1].address {
+		return nil, nil
+	}
+
+	// Binary search. Search until low, high are separated by 1.
+	low, high := 0, len(a.m)
+	for low+1 < high {
+		mid := (low + high) / 2
+		v := a.m[mid].address
+		if addr == v {
+			low = mid
+			break
+		} else if addr > v {
+			low = mid
+		} else {
+			high = mid
+		}
+	}
+
+	// Address is between a.m[low] and a.m[high].
+	// Pick low, as it represents [low, high).
+	f := []plugin.Frame{
+		{
+			Func: a.m[low].name,
+		},
+	}
+	return f, nil
+}