1 files changed, 291 insertions, 0 deletions
diff --git a/vendor/github.com/maruel/panicparse/stack/source.go b/vendor/github.com/maruel/panicparse/stack/source.go
new file mode 100644
index 000000000..f09e67336
--- /dev/null
+++ b/vendor/github.com/maruel/panicparse/stack/source.go
@@ -0,0 +1,291 @@
+// Copyright 2015 Marc-Antoine Ruel. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+// This file contains the code to process sources, to be able to deduct the
+// original types.
+
+package stack
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"io/ioutil"
+	"log"
+	"math"
+	"strings"
+)
+
+// cache is a cache of sources on the file system.
+type cache struct {
+	files  map[string][]byte
+	parsed map[string]*parsedFile
+}
+
+// Augment processes source files to improve calls to be more descriptive.
+//
+// It modifies goroutines in place.
+func Augment(goroutines []Goroutine) {
+	c := &cache{}
+	for i := range goroutines {
+		c.augmentGoroutine(&goroutines[i])
+	}
+}
+
+// augmentGoroutine processes source files to improve call to be more
+// descriptive.
+//
+// It modifies the routine.
+func (c *cache) augmentGoroutine(goroutine *Goroutine) {
+	if c.files == nil {
+		c.files = map[string][]byte{}
+	}
+	if c.parsed == nil {
+		c.parsed = map[string]*parsedFile{}
+	}
+	// For each call site, look at the next call and populate it. Then we can
+	// walk back and reformat things.
+	for i := range goroutine.Stack.Calls {
+		c.load(goroutine.Stack.Calls[i].SourcePath)
+	}
+
+	// Once all loaded, we can look at the next call when available.
+	for i := 1; i < len(goroutine.Stack.Calls); i++ {
+		// Get the AST from the previous call and process the call line with it.
+		if f := c.getFuncAST(&goroutine.Stack.Calls[i]); f != nil {
+			processCall(&goroutine.Stack.Calls[i], f)
+		}
+	}
+}
+
+// Private stuff.
+
+// load loads a source file and parses the AST tree. Failures are ignored.
+func (c *cache) load(fileName string) {
+	if _, ok := c.parsed[fileName]; ok {
+		return
+	}
+	c.parsed[fileName] = nil
+	if !strings.HasSuffix(fileName, ".go") {
+		// Ignore C and assembly.
+		c.files[fileName] = nil
+		return
+	}
+	log.Printf("load(%s)", fileName)
+	if _, ok := c.files[fileName]; !ok {
+		var err error
+		if c.files[fileName], err = ioutil.ReadFile(fileName); err != nil {
+			log.Printf("Failed to read %s: %s", fileName, err)
+			c.files[fileName] = nil
+			return
+		}
+	}
+	fset := token.NewFileSet()
+	src := c.files[fileName]
+	parsed, err := parser.ParseFile(fset, fileName, src, 0)
+	if err != nil {
+		log.Printf("Failed to parse %s: %s", fileName, err)
+		return
+	}
+	// Convert the line number into raw file offset.
+	offsets := []int{0, 0}
+	start := 0
+	for l := 1; start < len(src); l++ {
+		start += bytes.IndexByte(src[start:], '\n') + 1
+		offsets = append(offsets, start)
+	}
+	c.parsed[fileName] = &parsedFile{offsets, parsed}
+}
+
+func (c *cache) getFuncAST(call *Call) *ast.FuncDecl {
+	if p := c.parsed[call.SourcePath]; p != nil {
+		return p.getFuncAST(call.Func.Name(), call.Line)
+	}
+	return nil
+}
+
+type parsedFile struct {
+	lineToByteOffset []int
+	parsed           *ast.File
+}
+
+// getFuncAST gets the callee site function AST representation for the code
+// inside the function f at line l.
+func (p *parsedFile) getFuncAST(f string, l int) (d *ast.FuncDecl) {
+	// Walk the AST to find the lineToByteOffset that fits the line number.
+	var lastFunc *ast.FuncDecl
+	var found ast.Node
+	// Inspect() goes depth first. This means for example that a function like:
+	// func a() {
+	//   b := func() {}
+	//   c()
+	// }
+	//
+	// Were we are looking at the c() call can return confused values. It is
+	// important to look at the actual ast.Node hierarchy.
+	ast.Inspect(p.parsed, func(n ast.Node) bool {
+		if d != nil {
+			return false
+		}
+		if n == nil {
+			return true
+		}
+		if found != nil {
+			// We are walking up.
+		}
+		if int(n.Pos()) >= p.lineToByteOffset[l] {
+			// We are expecting a ast.CallExpr node. It can be harder to figure out
+			// when there are multiple calls on a single line, as the stack trace
+			// doesn't have file byte offset information, only line based.
+			// gofmt will always format to one function call per line but there can
+			// be edge cases, like:
+			//   a = A{Foo(), Bar()}
+			d = lastFunc
+			//p.processNode(call, n)
+			return false
+		} else if f, ok := n.(*ast.FuncDecl); ok {
+			lastFunc = f
+		}
+		return true
+	})
+	return
+}
+
+func name(n ast.Node) string {
+	if _, ok := n.(*ast.InterfaceType); ok {
+		return "interface{}"
+	}
+	if i, ok := n.(*ast.Ident); ok {
+		return i.Name
+	}
+	if _, ok := n.(*ast.FuncType); ok {
+		return "func"
+	}
+	if s, ok := n.(*ast.SelectorExpr); ok {
+		return s.Sel.Name
+	}
+	// TODO(maruel): Implement anything missing.
+	return "<unknown>"
+}
+
+// fieldToType returns the type name and whether if it's an ellipsis.
+func fieldToType(f *ast.Field) (string, bool) {
+	switch arg := f.Type.(type) {
+	case *ast.ArrayType:
+		return "[]" + name(arg.Elt), false
+	case *ast.Ellipsis:
+		return name(arg.Elt), true
+	case *ast.FuncType:
+		// Do not print the function signature to not overload the trace.
+		return "func", false
+	case *ast.Ident:
+		return arg.Name, false
+	case *ast.InterfaceType:
+		return "interface{}", false
+	case *ast.SelectorExpr:
+		return arg.Sel.Name, false
+	case *ast.StarExpr:
+		return "*" + name(arg.X), false
+	default:
+		// TODO(maruel): Implement anything missing.
+		return "<unknown>", false
+	}
+}
+
+// extractArgumentsType returns the name of the type of each input argument.
+func extractArgumentsType(f *ast.FuncDecl) ([]string, bool) {
+	var fields []*ast.Field
+	if f.Recv != nil {
+		if len(f.Recv.List) != 1 {
+			panic("Expect only one receiver; please fix panicparse's code")
+		}
+		// If it is an object receiver (vs a pointer receiver), its address is not
+		// printed in the stack trace so it needs to be ignored.
+		if _, ok := f.Recv.List[0].Type.(*ast.StarExpr); ok {
+			fields = append(fields, f.Recv.List[0])
+		}
+	}
+	var types []string
+	extra := false
+	for _, arg := range append(fields, f.Type.Params.List...) {
+		// Assert that extra is only set on the last item of fields?
+		var t string
+		t, extra = fieldToType(arg)
+		mult := len(arg.Names)
+		if mult == 0 {
+			mult = 1
+		}
+		for i := 0; i < mult; i++ {
+			types = append(types, t)
+		}
+	}
+	return types, extra
+}
+
+// processCall walks the function and populate call accordingly.
+func processCall(call *Call, f *ast.FuncDecl) {
+	values := make([]uint64, len(call.Args.Values))
+	for i := range call.Args.Values {
+		values[i] = call.Args.Values[i].Value
+	}
+	index := 0
+	pop := func() uint64 {
+		if len(values) != 0 {
+			x := values[0]
+			values = values[1:]
+			index++
+			return x
+		}
+		return 0
+	}
+	popName := func() string {
+		n := call.Args.Values[index].Name
+		v := pop()
+		if len(n) == 0 {
+			return fmt.Sprintf("0x%x", v)
+		}
+		return n
+	}
+
+	types, extra := extractArgumentsType(f)
+	for i := 0; len(values) != 0; i++ {
+		var t string
+		if i >= len(types) {
+			if !extra {
+				// These are unexpected value! Print them as hex.
+				call.Args.Processed = append(call.Args.Processed, popName())
+				continue
+			}
+			t = types[len(types)-1]
+		} else {
+			t = types[i]
+		}
+		switch t {
+		case "float32":
+			call.Args.Processed = append(call.Args.Processed, fmt.Sprintf("%g", math.Float32frombits(uint32(pop()))))
+		case "float64":
+			call.Args.Processed = append(call.Args.Processed, fmt.Sprintf("%g", math.Float64frombits(pop())))
+		case "int", "int8", "int16", "int32", "int64", "uint", "uint8", "uint16", "uint32", "uint64":
+			call.Args.Processed = append(call.Args.Processed, fmt.Sprintf("%d", pop()))
+		case "string":
+			call.Args.Processed = append(call.Args.Processed, fmt.Sprintf("%s(%s, len=%d)", t, popName(), pop()))
+		default:
+			if strings.HasPrefix(t, "*") {
+				call.Args.Processed = append(call.Args.Processed, fmt.Sprintf("%s(%s)", t, popName()))
+			} else if strings.HasPrefix(t, "[]") {
+				call.Args.Processed = append(call.Args.Processed, fmt.Sprintf("%s(%s len=%d cap=%d)", t, popName(), pop(), pop()))
+			} else {
+				// Assumes it's an interface. For now, discard the object value, which
+				// is probably not a good idea.
+				call.Args.Processed = append(call.Args.Processed, fmt.Sprintf("%s(%s)", t, popName()))
+				pop()
+			}
+		}
+		if len(values) == 0 && call.Args.Elided {
+			return
+		}
+	}
+}