1 files changed, 98 insertions, 0 deletions
diff --git a/vendor/github.com/stvp/roll/stack.go b/vendor/github.com/stvp/roll/stack.go
new file mode 100644
index 000000000..c50425491
--- /dev/null
+++ b/vendor/github.com/stvp/roll/stack.go
@@ -0,0 +1,98 @@
+package roll
+
+import (
+	"fmt"
+	"hash/crc32"
+	"os"
+	"runtime"
+	"strings"
+)
+
+var (
+	knownFilePathPatterns = []string{
+		"github.com/",
+		"code.google.com/",
+		"bitbucket.org/",
+		"launchpad.net/",
+		"gopkg.in/",
+	}
+)
+
+func getCallers(skip int) (pc []uintptr) {
+	pc = make([]uintptr, 1000)
+	i := runtime.Callers(skip+1, pc)
+	return pc[0:i]
+}
+
+// -- rollbarFrames
+
+type rollbarFrame struct {
+	Filename string `json:"filename"`
+	Method   string `json:"method"`
+	Line     int    `json:"lineno"`
+}
+
+type rollbarFrames []rollbarFrame
+
+// buildRollbarFrames takes a slice of function pointers and returns a Rollbar
+// API payload containing the filename, method name, and line number of each
+// function.
+func buildRollbarFrames(callers []uintptr) (frames rollbarFrames) {
+	frames = rollbarFrames{}
+
+	// 2016-08-24 - runtime.CallersFrames was added in Go 1.7, which should
+	// replace the following code when roll is able to require Go 1.7+.
+	for _, caller := range callers {
+		frame := rollbarFrame{
+			Filename: "???",
+			Method:   "???",
+		}
+		if fn := runtime.FuncForPC(caller); fn != nil {
+			name, line := fn.FileLine(caller)
+			frame.Filename = scrubFile(name)
+			frame.Line = line
+			frame.Method = scrubFunction(fn.Name())
+		}
+		frames = append(frames, frame)
+	}
+
+	return frames
+}
+
+// fingerprint returns a checksum that uniquely identifies a stacktrace by the
+// filename, method name, and line number of every frame in the stack.
+func (f rollbarFrames) fingerprint() string {
+	hash := crc32.NewIEEE()
+	for _, frame := range f {
+		fmt.Fprintf(hash, "%s%s%d", frame.Filename, frame.Method, frame.Line)
+	}
+	return fmt.Sprintf("%x", hash.Sum32())
+}
+
+// -- Helpers
+
+// scrubFile removes unneeded information from the path of a source file. This
+// makes them shorter in Rollbar UI as well as making them the same, regardless
+// of the machine the code was compiled on.
+//
+// Example:
+//   /home/foo/go/src/github.com/stvp/roll/rollbar.go -> github.com/stvp/roll/rollbar.go
+func scrubFile(s string) string {
+	var i int
+	for _, pattern := range knownFilePathPatterns {
+		i = strings.Index(s, pattern)
+		if i != -1 {
+			return s[i:]
+		}
+	}
+	return s
+}
+
+// scrubFunction removes unneeded information from the full name of a function.
+//
+// Example:
+//   github.com/stvp/roll.getCallers -> roll.getCallers
+func scrubFunction(name string) string {
+	end := strings.LastIndex(name, string(os.PathSeparator))
+	return name[end+1 : len(name)]
+}