github.com/gocuntian/go@v0.0.0-20160610041250-fee02d270bf8/src/cmd/link/internal/ld/util.go (about)

     1  // Copyright 2015 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package ld
     6  
     7  import (
     8  	"bytes"
     9  	"encoding/binary"
    10  	"log"
    11  	"os"
    12  	"runtime"
    13  	"runtime/pprof"
    14  	"strings"
    15  	"time"
    16  )
    17  
    18  func cstring(x []byte) string {
    19  	i := bytes.IndexByte(x, '\x00')
    20  	if i >= 0 {
    21  		x = x[:i]
    22  	}
    23  	return string(x)
    24  }
    25  
    26  func tokenize(s string) []string {
    27  	var f []string
    28  	for {
    29  		s = strings.TrimLeft(s, " \t\r\n")
    30  		if s == "" {
    31  			break
    32  		}
    33  		quote := false
    34  		i := 0
    35  		for ; i < len(s); i++ {
    36  			if s[i] == '\'' {
    37  				if quote && i+1 < len(s) && s[i+1] == '\'' {
    38  					i++
    39  					continue
    40  				}
    41  				quote = !quote
    42  			}
    43  			if !quote && (s[i] == ' ' || s[i] == '\t' || s[i] == '\r' || s[i] == '\n') {
    44  				break
    45  			}
    46  		}
    47  		next := s[:i]
    48  		s = s[i:]
    49  		if strings.Contains(next, "'") {
    50  			var buf []byte
    51  			quote := false
    52  			for i := 0; i < len(next); i++ {
    53  				if next[i] == '\'' {
    54  					if quote && i+1 < len(next) && next[i+1] == '\'' {
    55  						i++
    56  						buf = append(buf, '\'')
    57  					}
    58  					quote = !quote
    59  					continue
    60  				}
    61  				buf = append(buf, next[i])
    62  			}
    63  			next = string(buf)
    64  		}
    65  		f = append(f, next)
    66  	}
    67  	return f
    68  }
    69  
    70  var atExitFuncs []func()
    71  
    72  func AtExit(f func()) {
    73  	atExitFuncs = append(atExitFuncs, f)
    74  }
    75  
    76  func Exit(code int) {
    77  	for i := len(atExitFuncs) - 1; i >= 0; i-- {
    78  		f := atExitFuncs[i]
    79  		atExitFuncs = atExitFuncs[:i]
    80  		f()
    81  	}
    82  	os.Exit(code)
    83  }
    84  
    85  var (
    86  	cpuprofile     string
    87  	memprofile     string
    88  	memprofilerate int64
    89  )
    90  
    91  func startProfile() {
    92  	if cpuprofile != "" {
    93  		f, err := os.Create(cpuprofile)
    94  		if err != nil {
    95  			log.Fatalf("%v", err)
    96  		}
    97  		if err := pprof.StartCPUProfile(f); err != nil {
    98  			log.Fatalf("%v", err)
    99  		}
   100  		AtExit(pprof.StopCPUProfile)
   101  	}
   102  	if memprofile != "" {
   103  		if memprofilerate != 0 {
   104  			runtime.MemProfileRate = int(memprofilerate)
   105  		}
   106  		f, err := os.Create(memprofile)
   107  		if err != nil {
   108  			log.Fatalf("%v", err)
   109  		}
   110  		AtExit(func() {
   111  			runtime.GC() // profile all outstanding allocations
   112  			if err := pprof.WriteHeapProfile(f); err != nil {
   113  				log.Fatalf("%v", err)
   114  			}
   115  		})
   116  	}
   117  }
   118  
   119  func artrim(x []byte) string {
   120  	i := 0
   121  	j := len(x)
   122  	for i < len(x) && x[i] == ' ' {
   123  		i++
   124  	}
   125  	for j > i && x[j-1] == ' ' {
   126  		j--
   127  	}
   128  	return string(x[i:j])
   129  }
   130  
   131  func stringtouint32(x []uint32, s string) {
   132  	for i := 0; len(s) > 0; i++ {
   133  		var buf [4]byte
   134  		s = s[copy(buf[:], s):]
   135  		x[i] = binary.LittleEndian.Uint32(buf[:])
   136  	}
   137  }
   138  
   139  var start = time.Now()
   140  
   141  func elapsed() float64 {
   142  	return time.Since(start).Seconds()
   143  }