github.com/kaydxh/golang@v0.0.131/go/runtime/stack.go (about)

     1  /*
     2   *Copyright (c) 2022, kaydxh
     3   *
     4   *Permission is hereby granted, free of charge, to any person obtaining a copy
     5   *of this software and associated documentation files (the "Software"), to deal
     6   *in the Software without restriction, including without limitation the rights
     7   *to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     8   *copies of the Software, and to permit persons to whom the Software is
     9   *furnished to do so, subject to the following conditions:
    10   *
    11   *The above copyright notice and this permission notice shall be included in all
    12   *copies or substantial portions of the Software.
    13   *
    14   *THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    15   *IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    16   *FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    17   *AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    18   *LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    19   *OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
    20   *SOFTWARE.
    21   */
    22  package runtime
    23  
    24  import (
    25  	"bytes"
    26  	"errors"
    27  	"fmt"
    28  	"os"
    29  	"runtime/debug"
    30  	"strings"
    31  )
    32  
    33  func FormatStack() ([]byte, error) {
    34  	debugStack := debug.Stack()
    35  	return prettyStack{}.parse(debugStack)
    36  }
    37  
    38  type prettyStack struct {
    39  }
    40  
    41  func (s prettyStack) parse(debugStack []byte) ([]byte, error) {
    42  	var err error
    43  	buf := &bytes.Buffer{}
    44  
    45  	fmt.Fprintf(buf, "\n")
    46  	fmt.Fprintf(buf, " panic: ")
    47  	fmt.Fprintf(buf, "\n")
    48  
    49  	// process debug stack info
    50  	stack := strings.Split(string(debugStack), "\n")
    51  	lines := []string{}
    52  
    53  	// locate panic line, as we may have nested panics
    54  	for i := len(stack) - 1; i > 0; i-- {
    55  		lines = append(lines, stack[i])
    56  		if strings.HasPrefix(stack[i], "panic(") {
    57  			lines = lines[0 : len(lines)-2] // remove boilerplate
    58  			break
    59  		}
    60  	}
    61  
    62  	// reverse
    63  	for i := len(lines)/2 - 1; i >= 0; i-- {
    64  		opp := len(lines) - 1 - i
    65  		lines[i], lines[opp] = lines[opp], lines[i]
    66  	}
    67  
    68  	// decorate
    69  	for i, line := range lines {
    70  		lines[i], err = s.decorateLine(line, i)
    71  		if err != nil {
    72  			return nil, err
    73  		}
    74  	}
    75  
    76  	for _, l := range lines {
    77  		fmt.Fprintf(buf, "%s", l)
    78  	}
    79  	return buf.Bytes(), nil
    80  }
    81  
    82  func (s prettyStack) decorateLine(line string, num int) (string, error) {
    83  	line = strings.TrimSpace(line)
    84  	if strings.HasPrefix(line, "\t") || strings.Contains(line, ".go:") {
    85  		return s.decorateSourceLine(line, num)
    86  	} else if strings.HasSuffix(line, ")") {
    87  		return s.decorateFuncCallLine(line, num)
    88  	} else {
    89  		if strings.HasPrefix(line, "\t") {
    90  			return strings.Replace(line, "\t", "      ", 1), nil
    91  		} else {
    92  			return fmt.Sprintf("    %s\n", line), nil
    93  		}
    94  	}
    95  }
    96  
    97  func (s prettyStack) decorateFuncCallLine(line string, num int) (string, error) {
    98  	idx := strings.LastIndex(line, "(")
    99  	if idx < 0 {
   100  		return "", errors.New("not a func call line")
   101  	}
   102  
   103  	buf := &bytes.Buffer{}
   104  	pkg := line[0:idx]
   105  	// addr := line[idx:]
   106  	method := ""
   107  
   108  	if idx := strings.LastIndex(pkg, string(os.PathSeparator)); idx < 0 {
   109  		if idx := strings.Index(pkg, "."); idx > 0 {
   110  			method = pkg[idx:]
   111  			pkg = pkg[0:idx]
   112  		}
   113  	} else {
   114  		method = pkg[idx+1:]
   115  		pkg = pkg[0 : idx+1]
   116  		if idx := strings.Index(method, "."); idx > 0 {
   117  			pkg += method[0:idx]
   118  			method = method[idx:]
   119  		}
   120  	}
   121  
   122  	if num == 0 {
   123  		fmt.Fprintf(buf, " -> ")
   124  	} else {
   125  		fmt.Fprintf(buf, "    ")
   126  	}
   127  	fmt.Fprintf(buf, "%s", pkg)
   128  	fmt.Fprintf(buf, "%s\n", method)
   129  	return buf.String(), nil
   130  }
   131  
   132  func (s prettyStack) decorateSourceLine(line string, num int) (string, error) {
   133  	idx := strings.LastIndex(line, ".go:")
   134  	if idx < 0 {
   135  		return "", errors.New("not a source line")
   136  	}
   137  
   138  	buf := &bytes.Buffer{}
   139  	path := line[0 : idx+3]
   140  	lineno := line[idx+3:]
   141  
   142  	idx = strings.LastIndex(path, string(os.PathSeparator))
   143  	dir := path[0 : idx+1]
   144  	file := path[idx+1:]
   145  
   146  	idx = strings.Index(lineno, " ")
   147  	if idx > 0 {
   148  		lineno = lineno[0:idx]
   149  	}
   150  
   151  	if num == 1 {
   152  		fmt.Fprintf(buf, " -> ")
   153  	} else {
   154  		fmt.Fprintf(buf, "    ")
   155  	}
   156  	fmt.Fprintf(buf, "%s", dir)
   157  	fmt.Fprintf(buf, "%s", file)
   158  	fmt.Fprintf(buf, "%s", lineno)
   159  
   160  	if num == 1 {
   161  		fmt.Fprintf(buf, "\n")
   162  	}
   163  	fmt.Fprintf(buf, "\n")
   164  
   165  	return buf.String(), nil
   166  }