github.com/euank/go@v0.0.0-20160829210321-495514729181/src/internal/trace/parser_test.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 trace
     6  
     7  import (
     8  	"bytes"
     9  	"io/ioutil"
    10  	"path/filepath"
    11  	"strings"
    12  	"testing"
    13  )
    14  
    15  func TestCorruptedInputs(t *testing.T) {
    16  	// These inputs crashed parser previously.
    17  	tests := []string{
    18  		"gotrace\x00\x020",
    19  		"gotrace\x00Q00\x020",
    20  		"gotrace\x00T00\x020",
    21  		"gotrace\x00\xc3\x0200",
    22  		"go 1.5 trace\x00\x00\x00\x00\x020",
    23  		"go 1.5 trace\x00\x00\x00\x00Q00\x020",
    24  		"go 1.5 trace\x00\x00\x00\x00T00\x020",
    25  		"go 1.5 trace\x00\x00\x00\x00\xc3\x0200",
    26  	}
    27  	for _, data := range tests {
    28  		events, err := Parse(strings.NewReader(data), "")
    29  		if err == nil || events != nil {
    30  			t.Fatalf("no error on input: %q", data)
    31  		}
    32  	}
    33  }
    34  
    35  func TestParseCanned(t *testing.T) {
    36  	files, err := ioutil.ReadDir("./testdata")
    37  	if err != nil {
    38  		t.Fatalf("failed to read ./testdata: %v", err)
    39  	}
    40  	for _, f := range files {
    41  		data, err := ioutil.ReadFile(filepath.Join("./testdata", f.Name()))
    42  		if err != nil {
    43  			t.Fatalf("failed to read input file: %v", err)
    44  		}
    45  		// Instead of Parse that requires a proper binary name for old traces,
    46  		// we use 'parse' that omits symbol lookup if an empty string is given.
    47  		_, _, err = parse(bytes.NewReader(data), "")
    48  		switch {
    49  		case strings.HasSuffix(f.Name(), "_good"):
    50  			if err != nil {
    51  				t.Errorf("failed to parse good trace %v: %v", f.Name(), err)
    52  			}
    53  		case strings.HasSuffix(f.Name(), "_unordered"):
    54  			if err != ErrTimeOrder {
    55  				t.Errorf("unordered trace is not detected %v: %v", f.Name(), err)
    56  			}
    57  		default:
    58  			t.Errorf("unknown input file suffix: %v", f.Name())
    59  		}
    60  	}
    61  }
    62  
    63  func TestParseVersion(t *testing.T) {
    64  	tests := map[string]int{
    65  		"go 1.5 trace\x00\x00\x00\x00": 1005,
    66  		"go 1.7 trace\x00\x00\x00\x00": 1007,
    67  		"go 1.10 trace\x00\x00\x00":    1010,
    68  		"go 1.25 trace\x00\x00\x00":    1025,
    69  		"go 1.234 trace\x00\x00":       1234,
    70  		"go 1.2345 trace\x00":          -1,
    71  		"go 0.0 trace\x00\x00\x00\x00": -1,
    72  		"go a.b trace\x00\x00\x00\x00": -1,
    73  	}
    74  	for header, ver := range tests {
    75  		ver1, err := parseHeader([]byte(header))
    76  		if ver == -1 {
    77  			if err == nil {
    78  				t.Fatalf("no error on input: %q, version %v", header, ver1)
    79  			}
    80  		} else {
    81  			if err != nil {
    82  				t.Fatalf("failed to parse: %q (%v)", header, err)
    83  			}
    84  			if ver != ver1 {
    85  				t.Fatalf("wrong version: %v, want %v, input: %q", ver1, ver, header)
    86  			}
    87  		}
    88  	}
    89  }
    90  
    91  func TestTimestampOverflow(t *testing.T) {
    92  	// Test that parser correctly handles large timestamps (long tracing).
    93  	w := newWriter()
    94  	w.emit(EvBatch, 0, 0)
    95  	w.emit(EvFrequency, 1e9)
    96  	for ts := uint64(1); ts < 1e16; ts *= 2 {
    97  		w.emit(EvGoCreate, ts, ts, 0, 0)
    98  	}
    99  	if _, err := Parse(w, ""); err != nil {
   100  		t.Fatalf("failed to parse: %v", err)
   101  	}
   102  }
   103  
   104  type writer struct {
   105  	bytes.Buffer
   106  }
   107  
   108  func newWriter() *writer {
   109  	w := new(writer)
   110  	w.Write([]byte("go 1.7 trace\x00\x00\x00\x00"))
   111  	return w
   112  }
   113  
   114  func (w *writer) emit(typ byte, args ...uint64) {
   115  	nargs := byte(len(args)) - 1
   116  	if nargs > 3 {
   117  		nargs = 3
   118  	}
   119  	buf := []byte{typ | nargs<<6}
   120  	if nargs == 3 {
   121  		buf = append(buf, 0)
   122  	}
   123  	for _, a := range args {
   124  		buf = appendVarint(buf, a)
   125  	}
   126  	if nargs == 3 {
   127  		buf[1] = byte(len(buf) - 2)
   128  	}
   129  	n, err := w.Write(buf)
   130  	if n != len(buf) || err != nil {
   131  		panic("failed to write")
   132  	}
   133  }
   134  
   135  func appendVarint(buf []byte, v uint64) []byte {
   136  	for ; v >= 0x80; v >>= 7 {
   137  		buf = append(buf, 0x80|byte(v))
   138  	}
   139  	buf = append(buf, byte(v))
   140  	return buf
   141  }