1 files changed, 157 insertions, 0 deletions
diff --git a/Godeps/_workspace/src/github.com/obscuren/qml/log.go b/Godeps/_workspace/src/github.com/obscuren/qml/log.go
new file mode 100644
index 000000000..5301e63b0
--- /dev/null
+++ b/Godeps/_workspace/src/github.com/obscuren/qml/log.go
@@ -0,0 +1,157 @@
+package qml
+
+// #include "capi.h"
+//
+import "C"
+
+import (
+	"fmt"
+	"log"
+	"path/filepath"
+	"strings"
+)
+
+// SetLogger sets the target for messages logged by the qml package,
+// including console.log and related calls from within qml code.
+//
+// The logger value must implement either the StdLogger interface,
+// which is satisfied by the standard *log.Logger type, or the QmlLogger
+// interface, which offers more control over the logged message.
+//
+// If no logger is provided, the qml package will send messages to the
+// default log package logger. This behavior may also be restored by
+// providing a nil logger to this function.
+func SetLogger(logger interface{}) {
+	if logger == nil {
+		logHandler = defaultLogger{}
+		return
+	}
+	if qmll, ok := logger.(QmlLogger); ok {
+		logHandler = qmll
+		return
+	}
+	if stdl, ok := logger.(StdLogger); ok {
+		logHandler = wrappedStdLogger{stdl}
+		return
+	}
+	panic("unsupported logger interface")
+}
+
+// The QmlLogger interface may be implemented to better control how
+// log messages from the qml package are handled. Values that
+// implement either StdLogger or QmlLogger may be provided to the
+// SetLogger function.
+type QmlLogger interface {
+	// QmlOutput is called whenever a new message is available for logging.
+	// The message value must not be used after the method returns.
+	QmlOutput(message LogMessage) error
+}
+
+// The StdLogger interface is implemented by standard *log.Logger values.
+// Values that implement either StdLogger or QmlLogger may be provided
+// to the SetLogger function.
+type StdLogger interface {
+	// Output is called whenever a new message is available for logging.
+	// See the standard log.Logger type for more details.
+	Output(calldepth int, s string) error
+}
+
+// NOTE: LogMessage is an interface to avoid allocating and copying
+// several strings for each logged message.
+
+// LogMessage is implemented by values provided to QmlLogger.QmlOutput.
+type LogMessage interface {
+	Severity() LogSeverity
+	Text() string
+	File() string
+	Line() int
+
+	String() string // returns "file:line: text"
+
+	privateMarker()
+}
+
+type LogSeverity int
+
+const (
+	LogDebug LogSeverity = iota
+	LogWarning
+	LogCritical
+	LogFatal
+)
+
+var logHandler QmlLogger = defaultLogger{}
+
+type defaultLogger struct{}
+
+func (defaultLogger) QmlOutput(msg LogMessage) error {
+	log.Println(msg.String())
+	return nil
+}
+
+func init() {
+	// Install the C++ log handler that diverts calls to the hook below.
+	C.installLogHandler()
+}
+
+//export hookLogHandler
+func hookLogHandler(cmsg *C.LogMessage) {
+	// Workarund for QTBUG-35943
+	text := unsafeString(cmsg.text, cmsg.textLen)
+	if strings.HasPrefix(text, `"Qt Warning: Compose file:`) {
+		return
+	}
+	msg := logMessage{c: cmsg}
+	logHandler.QmlOutput(&msg)
+	msg.invalid = true
+}
+
+type wrappedStdLogger struct {
+	StdLogger
+}
+
+func (l wrappedStdLogger) QmlOutput(msg LogMessage) error {
+	return l.Output(0, msg.String())
+}
+
+type logMessage struct {
+	c *C.LogMessage
+
+	// invalid flags that cmsg points to unreliable memory,
+	// since the log hook has already returned.
+	invalid bool
+}
+
+func (m *logMessage) assertValid() {
+	if m.invalid {
+		panic("attempted to use log message outside of log hook")
+	}
+}
+
+func (m *logMessage) Severity() LogSeverity {
+	return LogSeverity(m.c.severity)
+}
+
+func (m *logMessage) Line() int {
+	m.assertValid()
+	return int(m.c.line)
+}
+
+func (m *logMessage) String() string {
+	m.assertValid()
+	file := unsafeString(m.c.file, m.c.fileLen)
+	text := unsafeString(m.c.text, m.c.textLen)
+	return fmt.Sprintf("%s:%d: %s", filepath.Base(file), m.c.line, text)
+}
+
+func (m *logMessage) File() string {
+	m.assertValid()
+	return C.GoStringN(m.c.file, m.c.fileLen)
+}
+
+func (m *logMessage) Text() string {
+	m.assertValid()
+	return C.GoStringN(m.c.text, m.c.line)
+}
+
+func (*logMessage) privateMarker() {}