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author | Michael Muré <batolettre@gmail.com> | 2019-11-03 20:47:29 +0100 |
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committer | Michael Muré <batolettre@gmail.com> | 2019-11-03 20:47:29 +0100 |
commit | cb8236c9c22007eb622b7219c58d3342f1f53d50 (patch) | |
tree | e232e5362486065d9b28bb55b9791690efb50c08 /vendor/github.com/go-errors/errors/stackframe.go | |
parent | 163ea9c93306c387f84ff0b85c2d8fca4c01e449 (diff) | |
download | git-bug-cb8236c9c22007eb622b7219c58d3342f1f53d50.tar.gz |
termui: migrate to awesome-gocui instead of the old fork I had
Diffstat (limited to 'vendor/github.com/go-errors/errors/stackframe.go')
-rw-r--r-- | vendor/github.com/go-errors/errors/stackframe.go | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/vendor/github.com/go-errors/errors/stackframe.go b/vendor/github.com/go-errors/errors/stackframe.go new file mode 100644 index 00000000..750ab9a5 --- /dev/null +++ b/vendor/github.com/go-errors/errors/stackframe.go @@ -0,0 +1,102 @@ +package errors + +import ( + "bytes" + "fmt" + "io/ioutil" + "runtime" + "strings" +) + +// A StackFrame contains all necessary information about to generate a line +// in a callstack. +type StackFrame struct { + // The path to the file containing this ProgramCounter + File string + // The LineNumber in that file + LineNumber int + // The Name of the function that contains this ProgramCounter + Name string + // The Package that contains this function + Package string + // The underlying ProgramCounter + ProgramCounter uintptr +} + +// NewStackFrame popoulates a stack frame object from the program counter. +func NewStackFrame(pc uintptr) (frame StackFrame) { + + frame = StackFrame{ProgramCounter: pc} + if frame.Func() == nil { + return + } + frame.Package, frame.Name = packageAndName(frame.Func()) + + // pc -1 because the program counters we use are usually return addresses, + // and we want to show the line that corresponds to the function call + frame.File, frame.LineNumber = frame.Func().FileLine(pc - 1) + return + +} + +// Func returns the function that contained this frame. +func (frame *StackFrame) Func() *runtime.Func { + if frame.ProgramCounter == 0 { + return nil + } + return runtime.FuncForPC(frame.ProgramCounter) +} + +// String returns the stackframe formatted in the same way as go does +// in runtime/debug.Stack() +func (frame *StackFrame) String() string { + str := fmt.Sprintf("%s:%d (0x%x)\n", frame.File, frame.LineNumber, frame.ProgramCounter) + + source, err := frame.SourceLine() + if err != nil { + return str + } + + return str + fmt.Sprintf("\t%s: %s\n", frame.Name, source) +} + +// SourceLine gets the line of code (from File and Line) of the original source if possible. +func (frame *StackFrame) SourceLine() (string, error) { + data, err := ioutil.ReadFile(frame.File) + + if err != nil { + return "", New(err) + } + + lines := bytes.Split(data, []byte{'\n'}) + if frame.LineNumber <= 0 || frame.LineNumber >= len(lines) { + return "???", nil + } + // -1 because line-numbers are 1 based, but our array is 0 based + return string(bytes.Trim(lines[frame.LineNumber-1], " \t")), nil +} + +func packageAndName(fn *runtime.Func) (string, string) { + name := fn.Name() + pkg := "" + + // The name includes the path name to the package, which is unnecessary + // since the file name is already included. Plus, it has center dots. + // That is, we see + // runtime/debug.*T·ptrmethod + // and want + // *T.ptrmethod + // Since the package path might contains dots (e.g. code.google.com/...), + // we first remove the path prefix if there is one. + if lastslash := strings.LastIndex(name, "/"); lastslash >= 0 { + pkg += name[:lastslash] + "/" + name = name[lastslash+1:] + } + if period := strings.Index(name, "."); period >= 0 { + pkg += name[:period] + name = name[period+1:] + } + + name = strings.Replace(name, "·", ".", -1) + return pkg, name +} |