debug.mx raw

   1  // Portions copyright 2009 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 debug is a very partially implemented package to allow compilation.
   6  package debug
   7  
   8  import (
   9  	"fmt"
  10  	"runtime"
  11  	"strconv"
  12  	"bytes"
  13  )
  14  
  15  // SetMaxStack sets the maximum amount of memory that can be used by a single
  16  // goroutine stack.
  17  //
  18  // Not implemented.
  19  func SetMaxStack(n int) int {
  20  	return n
  21  }
  22  
  23  // PrintStack prints to standard error the stack trace returned by runtime.Stack.
  24  //
  25  // Not implemented.
  26  func PrintStack() {}
  27  
  28  // Stack returns a formatted stack trace of the goroutine that calls it.
  29  //
  30  // Not implemented.
  31  func Stack() []byte {
  32  	return nil
  33  }
  34  
  35  // ReadBuildInfo returns the build information embedded
  36  // in the running binary. The information is available only
  37  // in binaries built with module support.
  38  //
  39  // Not implemented.
  40  func ReadBuildInfo() (info *BuildInfo, ok bool) {
  41  	return &BuildInfo{GoVersion: runtime.Compiler + runtime.Version()}, true
  42  }
  43  
  44  // BuildInfo represents the build information read from
  45  // the running binary.
  46  type BuildInfo struct {
  47  	GoVersion string    // version of the Go toolchain that built the binary, e.g. "go1.19.2"
  48  	Path      string    // The main package path
  49  	Main      Module    // The module containing the main package
  50  	Deps      []*Module // Module dependencies
  51  	Settings  []BuildSetting
  52  }
  53  
  54  type BuildSetting struct {
  55  	// Key and Value describe the build setting.
  56  	// Key must not contain an equals sign, space, tab, or newline.
  57  	// Value must not contain newlines ('\n').
  58  	Key, Value string
  59  }
  60  
  61  // Module represents a module.
  62  type Module struct {
  63  	Path    string  // module path
  64  	Version string  // module version
  65  	Sum     string  // checksum
  66  	Replace *Module // replaced by this module
  67  }
  68  
  69  // Not implemented.
  70  func SetGCPercent(n int) int {
  71  	return n
  72  }
  73  
  74  // Start of stolen from big go. TODO: import/reuse without copy pasta.
  75  
  76  // quoteKey reports whether key is required to be quoted.
  77  func quoteKey(key string) bool {
  78  	return len(key) == 0 || bytes.ContainsAny(key, "= \t\r\n\"`")
  79  }
  80  
  81  // quoteValue reports whether value is required to be quoted.
  82  func quoteValue(value string) bool {
  83  	return bytes.ContainsAny(value, " \t\r\n\"`")
  84  }
  85  
  86  func (bi *BuildInfo) String() string {
  87  	buf := new(bytes.Buffer)
  88  	if bi.GoVersion != "" {
  89  		fmt.Fprintf(buf, "go\t%s\n", bi.GoVersion)
  90  	}
  91  	if bi.Path != "" {
  92  		fmt.Fprintf(buf, "path\t%s\n", bi.Path)
  93  	}
  94  	var formatMod func(string, Module)
  95  	formatMod = func(word string, m Module) {
  96  		buf.WriteString(word)
  97  		buf.WriteByte('\t')
  98  		buf.WriteString(m.Path)
  99  		buf.WriteByte('\t')
 100  		buf.WriteString(m.Version)
 101  		if m.Replace == nil {
 102  			buf.WriteByte('\t')
 103  			buf.WriteString(m.Sum)
 104  		} else {
 105  			buf.WriteByte('\n')
 106  			formatMod("=>", *m.Replace)
 107  		}
 108  		buf.WriteByte('\n')
 109  	}
 110  	if bi.Main != (Module{}) {
 111  		formatMod("mod", bi.Main)
 112  	}
 113  	for _, dep := range bi.Deps {
 114  		formatMod("dep", *dep)
 115  	}
 116  	for _, s := range bi.Settings {
 117  		key := s.Key
 118  		if quoteKey(key) {
 119  			key = strconv.Quote(key)
 120  		}
 121  		value := s.Value
 122  		if quoteValue(value) {
 123  			value = strconv.Quote(value)
 124  		}
 125  		fmt.Fprintf(buf, "build\t%s=%s\n", key, value)
 126  	}
 127  
 128  	return buf.String()
 129  }
 130