Source file src/internal/trace/raw/doc.go
1 // Copyright 2023 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 /* 6 Package raw provides an interface to interpret and emit Go execution traces. 7 It can interpret and emit execution traces in its wire format as well as a 8 bespoke but simple text format. 9 10 The readers and writers in this package perform no validation on or ordering of 11 the input, and so are generally unsuitable for analysis. However, they're very 12 useful for testing and debugging the tracer in the runtime and more sophisticated 13 trace parsers. 14 15 # Text format specification 16 17 The trace text format produced and consumed by this package is a line-oriented 18 format. 19 20 The first line in each text trace is the header line. 21 22 Trace Go1.XX 23 24 Following that is a series of event lines. Each event begins with an 25 event name, followed by zero or more named unsigned integer arguments. 26 Names are separated from their integer values by an '=' sign. Names can 27 consist of any UTF-8 character except '='. 28 29 For example: 30 31 EventName arg1=23 arg2=55 arg3=53 32 33 Any amount of whitespace is allowed to separate each token. Whitespace 34 is identified via unicode.IsSpace. 35 36 Some events have additional data on following lines. There are two such 37 special cases. 38 39 The first special case consists of events with trailing byte-oriented data. 40 The trailer begins on the following line from the event. That line consists 41 of a single argument 'data' and a Go-quoted string representing the byte data 42 within. Note: an explicit argument for the length is elided, because it's 43 just the length of the unquoted string. 44 45 For example: 46 47 String id=5 48 data="hello world\x00" 49 50 These events are identified in their spec by the HasData flag. 51 52 The second special case consists of stack events. These events are identified 53 by the IsStack flag. These events also have a trailing unsigned integer argument 54 describing the number of stack frame descriptors that follow. Each stack frame 55 descriptor is on its own line following the event, consisting of four signed 56 integer arguments: the PC, an integer describing the function name, an integer 57 describing the file name, and the line number in that file that function was at 58 at the time the stack trace was taken. 59 60 For example: 61 62 Stack id=5 n=2 63 pc=1241251 func=3 file=6 line=124 64 pc=7534345 func=6 file=3 line=64 65 */ 66 package raw 67