From 095e65c80004fd6c60273a007c9974c2f86402a0 Mon Sep 17 00:00:00 2001
From: RSWilli <bartel.wilhelm@gmail.com>
Date: Sat, 2 Sep 2023 00:04:14 +0200
Subject: [PATCH] some staticcheck fixes

---
 examples/custom_events/main.go          |  6 ++++-
 examples/decodebin/main.go              |  2 +-
 examples/launch/main.go                 |  2 +-
 examples/pad-probes/main.go             |  4 +++
 examples/playbin/main.go                |  4 +--
 examples/plugins/gofilesink/filesink.go | 30 ++++++++++-----------
 examples/plugins/gofilesrc/filesrc.go   | 36 ++++++++++++-------------
 examples/toc/main.go                    |  3 +--
 gst/app/gst_app_sink.go                 |  2 +-
 gst/c_util.go                           |  5 ++--
 gst/gst_bin.go                          | 12 ++++-----
 gst/gst_buffer.go                       |  3 +--
 gst/gst_device.go                       |  2 +-
 gst/gst_element.go                      |  8 +++---
 gst/gst_mapinfo.go                      |  2 +-
 gst/gst_pad.go                          |  2 +-
 gst/gst_pipeline.go                     |  4 +--
 gst/gst_registry.go                     |  4 +--
 gst/gst_stream_collection.go            |  2 +-
 gst/gst_structure.go                    |  4 +--
 20 files changed, 70 insertions(+), 67 deletions(-)

diff --git a/examples/custom_events/main.go b/examples/custom_events/main.go
index 39f285b..1445127 100644
--- a/examples/custom_events/main.go
+++ b/examples/custom_events/main.go
@@ -26,12 +26,16 @@ func createPipeline() (*gst.Pipeline, error) {
 		"audiotestsrc name=src ! queue max-size-time=2000000000 ! fakesink name=sink sync=true",
 	)
 
+	if err != nil {
+		return nil, err
+	}
+
 	// Retrieve the sink element
 	sinks, err := pipeline.GetSinkElements()
 	if err != nil {
 		return nil, err
 	} else if len(sinks) != 1 {
-		return nil, errors.New("Expected one sink back")
+		return nil, errors.New("expected one sink back")
 	}
 	sink := sinks[0]
 
diff --git a/examples/decodebin/main.go b/examples/decodebin/main.go
index 890ba7f..7319211 100644
--- a/examples/decodebin/main.go
+++ b/examples/decodebin/main.go
@@ -90,7 +90,7 @@ func buildPipeline() (*gst.Pipeline, error) {
 		fmt.Printf("New pad added, is_audio=%v, is_video=%v\n", isAudio, isVideo)
 
 		if !isAudio && !isVideo {
-			err := errors.New("Could not detect media stream type")
+			err := errors.New("could not detect media stream type")
 			// We can send errors directly to the pipeline bus if they occur.
 			// These will be handled downstream.
 			msg := gst.NewErrorMessage(self, gst.NewGError(1, err), fmt.Sprintf("Received caps: %s", caps.String()), nil)
diff --git a/examples/launch/main.go b/examples/launch/main.go
index e1772e5..1a2984b 100644
--- a/examples/launch/main.go
+++ b/examples/launch/main.go
@@ -16,7 +16,7 @@ import (
 
 func runPipeline(mainLoop *glib.MainLoop) error {
 	if len(os.Args) == 1 {
-		return errors.New("Pipeline string cannot be empty")
+		return errors.New("pipeline string cannot be empty")
 	}
 
 	gst.Init(&os.Args)
diff --git a/examples/pad-probes/main.go b/examples/pad-probes/main.go
index 9c02556..10ff891 100644
--- a/examples/pad-probes/main.go
+++ b/examples/pad-probes/main.go
@@ -29,6 +29,10 @@ func padProbes(mainLoop *glib.MainLoop) error {
 		"audiotestsrc name=src ! audio/x-raw,format=S16LE,channels=1 ! fakesink",
 	)
 
+	if err != nil {
+		return err
+	}
+
 	// Get the audiotestsrc element from the pipeline that GStreamer
 	// created for us while parsing the launch syntax above.
 	//
diff --git a/examples/playbin/main.go b/examples/playbin/main.go
index 0294f36..231b2f8 100644
--- a/examples/playbin/main.go
+++ b/examples/playbin/main.go
@@ -21,11 +21,9 @@ import (
 	"github.com/go-gst/go-gst/gst"
 )
 
-var srcURI string
-
 func playbin(mainLoop *glib.MainLoop) error {
 	if len(os.Args) < 2 {
-		return errors.New("Usage: playbin <uri>")
+		return errors.New("usage: playbin <uri>")
 	}
 
 	gst.Init(nil)
diff --git a/examples/plugins/gofilesink/filesink.go b/examples/plugins/gofilesink/filesink.go
index 2f16cb1..8e6a783 100644
--- a/examples/plugins/gofilesink/filesink.go
+++ b/examples/plugins/gofilesink/filesink.go
@@ -88,7 +88,7 @@ type settings struct {
 // Finally a structure is defined that implements (at a minimum) the glib.GoObject interface.
 // It is possible to signal to the bindings to inherit from other classes or implement other
 // interfaces via the registration and TypeInit processes.
-type fileSink struct {
+type FileSink struct {
 	// The settings for the element
 	settings *settings
 	// The current state of the element
@@ -97,9 +97,9 @@ type fileSink struct {
 
 // setLocation is a simple method to check the validity of a provided file path and set the
 // local value with it.
-func (f *fileSink) setLocation(path string) error {
+func (f *FileSink) setLocation(path string) error {
 	if f.state.started {
-		return errors.New("Changing the `location` property on a started `GoFileSink` is not supported")
+		return errors.New("changing the `location` property on a started `GoFileSink` is not supported")
 	}
 	f.settings.location = strings.TrimPrefix(path, "file://") // should obviously use url.URL and do actual parsing
 	return nil
@@ -111,9 +111,9 @@ func (f *fileSink) setLocation(path string) error {
 
 // Every element needs to provide its own constructor that returns an initialized glib.GoObjectSubclass
 // implementation. Here we simply create a new fileSink with zeroed settings and state objects.
-func (f *fileSink) New() glib.GoObjectSubclass {
+func (f *FileSink) New() glib.GoObjectSubclass {
 	CAT.Log(gst.LevelLog, "Initializing new fileSink object")
-	return &fileSink{
+	return &FileSink{
 		settings: &settings{},
 		state:    &state{},
 	}
@@ -121,7 +121,7 @@ func (f *fileSink) New() glib.GoObjectSubclass {
 
 // The ClassInit method should specify the metadata for this element and add any pad templates
 // and properties.
-func (f *fileSink) ClassInit(klass *glib.ObjectClass) {
+func (f *FileSink) ClassInit(klass *glib.ObjectClass) {
 	CAT.Log(gst.LevelLog, "Initializing gofilesink class")
 	class := gst.ToElementClass(klass)
 	class.SetMetadata(
@@ -150,7 +150,7 @@ func (f *fileSink) ClassInit(klass *glib.ObjectClass) {
 // SetProperty is called when a `value` is set to the property at index `id` in the
 // properties slice that we installed during ClassInit. It should attempt to register
 // the value locally or signal any errors that occur in the process.
-func (f *fileSink) SetProperty(self *glib.Object, id uint, value *glib.Value) {
+func (f *FileSink) SetProperty(self *glib.Object, id uint, value *glib.Value) {
 	param := properties[id]
 	switch param.Name() {
 	case "location":
@@ -173,7 +173,7 @@ func (f *fileSink) SetProperty(self *glib.Object, id uint, value *glib.Value) {
 
 // GetProperty is called to retrieve the value of the property at index `id` in the properties
 // slice provided at ClassInit.
-func (f *fileSink) GetProperty(self *glib.Object, id uint) *glib.Value {
+func (f *FileSink) GetProperty(self *glib.Object, id uint) *glib.Value {
 	param := properties[id]
 	switch param.Name() {
 	case "location":
@@ -196,7 +196,7 @@ func (f *fileSink) GetProperty(self *glib.Object, id uint) *glib.Value {
 // If the method is not overridden by the implementing struct, it will be inherited from the parent class.
 
 // Start is called to start the filesink. Open the file for writing and set the internal state.
-func (f *fileSink) Start(self *base.GstBaseSink) bool {
+func (f *FileSink) Start(self *base.GstBaseSink) bool {
 	if f.state.started {
 		self.ErrorMessage(gst.DomainResource, gst.ResourceErrorSettings, "GoFileSink is already started", "")
 		return false
@@ -225,7 +225,7 @@ func (f *fileSink) Start(self *base.GstBaseSink) bool {
 }
 
 // Stop is called to stop the element. Set the internal state and close the file.
-func (f *fileSink) Stop(self *base.GstBaseSink) bool {
+func (f *FileSink) Stop(self *base.GstBaseSink) bool {
 	if !f.state.started {
 		self.ErrorMessage(gst.DomainResource, gst.ResourceErrorSettings, "GoFileSink is not started", "")
 		return false
@@ -241,7 +241,7 @@ func (f *fileSink) Stop(self *base.GstBaseSink) bool {
 }
 
 // Render is called when a buffer is ready to be written to the file.
-func (f *fileSink) Render(self *base.GstBaseSink, buffer *gst.Buffer) gst.FlowReturn {
+func (f *FileSink) Render(self *base.GstBaseSink, buffer *gst.Buffer) gst.FlowReturn {
 	if !f.state.started {
 		self.ErrorMessage(gst.DomainResource, gst.ResourceErrorSettings, "GoFileSink is not started", "")
 		return gst.FlowError
@@ -263,16 +263,16 @@ func (f *fileSink) Render(self *base.GstBaseSink, buffer *gst.Buffer) gst.FlowRe
 // URIHandler implementations are the methods required by the GstURIHandler interface.
 
 // GetURI returns the currently configured URI
-func (f *fileSink) GetURI() string { return fmt.Sprintf("file://%s", f.settings.location) }
+func (f *FileSink) GetURI() string { return fmt.Sprintf("file://%s", f.settings.location) }
 
 // GetURIType returns the types of URI this element supports.
-func (f *fileSink) GetURIType() gst.URIType { return gst.URISource }
+func (f *FileSink) GetURIType() gst.URIType { return gst.URISource }
 
 // GetProtocols returns the protcols this element supports.
-func (f *fileSink) GetProtocols() []string { return []string{"file"} }
+func (f *FileSink) GetProtocols() []string { return []string{"file"} }
 
 // SetURI should set the URI that this element is working on.
-func (f *fileSink) SetURI(uri string) (bool, error) {
+func (f *FileSink) SetURI(uri string) (bool, error) {
 	if uri == "file://" {
 		return true, nil
 	}
diff --git a/examples/plugins/gofilesrc/filesrc.go b/examples/plugins/gofilesrc/filesrc.go
index d3a7a65..d89dbb5 100644
--- a/examples/plugins/gofilesrc/filesrc.go
+++ b/examples/plugins/gofilesrc/filesrc.go
@@ -90,7 +90,7 @@ type settings struct {
 // Finally a structure is defined that implements (at a minimum) the gst.GoElement interface.
 // It is possible to signal to the bindings to inherit from other classes or implement other
 // interfaces via the registration and TypeInit processes.
-type fileSrc struct {
+type FileSrc struct {
 	// The settings for the element
 	settings *settings
 	// The current state of the element
@@ -101,9 +101,9 @@ type fileSrc struct {
 
 // setLocation is a simple method to check the validity of a provided file path and set the
 // local value with it.
-func (f *fileSrc) setLocation(path string) error {
+func (f *FileSrc) setLocation(path string) error {
 	if f.state.started {
-		return errors.New("Changing the `location` property on a started `GoFileSrc` is not supported")
+		return errors.New("changing the `location` property on a started `GoFileSrc` is not supported")
 	}
 	f.settings.location = strings.TrimPrefix(path, "file://") // should obviously use url.URL and do actual parsing
 	return nil
@@ -115,9 +115,9 @@ func (f *fileSrc) setLocation(path string) error {
 
 // Every element needs to provide its own constructor that returns an initialized
 // glib.GoObjectSubclass and state objects.
-func (f *fileSrc) New() glib.GoObjectSubclass {
+func (f *FileSrc) New() glib.GoObjectSubclass {
 	CAT.Log(gst.LevelLog, "Initializing new fileSrc object")
-	return &fileSrc{
+	return &FileSrc{
 		settings: &settings{},
 		state:    &state{},
 	}
@@ -125,7 +125,7 @@ func (f *fileSrc) New() glib.GoObjectSubclass {
 
 // The ClassInit method should specify the metadata for this element and add any pad templates
 // and properties.
-func (f *fileSrc) ClassInit(klass *glib.ObjectClass) {
+func (f *FileSrc) ClassInit(klass *glib.ObjectClass) {
 	CAT.Log(gst.LevelLog, "Initializing gofilesrc class")
 	class := gst.ToElementClass(klass)
 	class.SetMetadata(
@@ -154,7 +154,7 @@ func (f *fileSrc) ClassInit(klass *glib.ObjectClass) {
 // SetProperty is called when a `value` is set to the property at index `id` in the
 // properties slice that we installed during ClassInit. It should attempt to register
 // the value locally or signal any errors that occur in the process.
-func (f *fileSrc) SetProperty(self *glib.Object, id uint, value *glib.Value) {
+func (f *FileSrc) SetProperty(self *glib.Object, id uint, value *glib.Value) {
 	param := properties[id]
 	switch param.Name() {
 	case "location":
@@ -177,7 +177,7 @@ func (f *fileSrc) SetProperty(self *glib.Object, id uint, value *glib.Value) {
 
 // GetProperty is called to retrieve the value of the property at index `id` in the properties
 // slice provided at ClassInit.
-func (f *fileSrc) GetProperty(self *glib.Object, id uint) *glib.Value {
+func (f *FileSrc) GetProperty(self *glib.Object, id uint) *glib.Value {
 	param := properties[id]
 	switch param.Name() {
 	case "location":
@@ -199,7 +199,7 @@ func (f *fileSrc) GetProperty(self *glib.Object, id uint) *glib.Value {
 // Constructed is called when the type system is done constructing the object. Any finalizations required
 // during the initialization process can be performed here. In this example, we set the format on our
 // underlying GstBaseSrc to bytes.
-func (f *fileSrc) Constructed(self *glib.Object) {
+func (f *FileSrc) Constructed(self *glib.Object) {
 	base.ToGstBaseSrc(self).Log(CAT, gst.LevelLog, "Setting format of GstBaseSrc to bytes")
 	base.ToGstBaseSrc(self).SetFormat(gst.FormatBytes)
 }
@@ -208,10 +208,10 @@ func (f *fileSrc) Constructed(self *glib.Object) {
 // If the method is not overridden by the implementing struct, it will be inherited from the parent class.
 
 // IsSeekable returns that we are, in fact, seekable.
-func (f *fileSrc) IsSeekable(*base.GstBaseSrc) bool { return true }
+func (f *FileSrc) IsSeekable(*base.GstBaseSrc) bool { return true }
 
 // GetSize will return the total size of the file at the configured location.
-func (f *fileSrc) GetSize(self *base.GstBaseSrc) (bool, int64) {
+func (f *FileSrc) GetSize(self *base.GstBaseSrc) (bool, int64) {
 	if !f.state.started {
 		return false, 0
 	}
@@ -220,7 +220,7 @@ func (f *fileSrc) GetSize(self *base.GstBaseSrc) (bool, int64) {
 
 // Start is called to start this element. In this example, the configured file is opened for reading,
 // and any error encountered in the process is posted to the pipeline.
-func (f *fileSrc) Start(self *base.GstBaseSrc) bool {
+func (f *FileSrc) Start(self *base.GstBaseSrc) bool {
 	if f.state.started {
 		self.ErrorMessage(gst.DomainResource, gst.ResourceErrorSettings, "GoFileSrc is already started", "")
 		return false
@@ -268,7 +268,7 @@ func (f *fileSrc) Start(self *base.GstBaseSrc) bool {
 }
 
 // Stop is called to stop the element. The file is closed and the local values are zeroed out.
-func (f *fileSrc) Stop(self *base.GstBaseSrc) bool {
+func (f *FileSrc) Stop(self *base.GstBaseSrc) bool {
 	if !f.state.started {
 		self.ErrorMessage(gst.DomainResource, gst.ResourceErrorSettings, "FileSrc is not started", "")
 		return false
@@ -290,7 +290,7 @@ func (f *fileSrc) Stop(self *base.GstBaseSrc) bool {
 // Fill is called to fill a pre-allocated buffer with the data at offset up to the given size.
 // Since we declared that we are seekable, we need to support the provided offset not necessarily matching
 // where we currently are in the file. This is why we store the position in the file locally.
-func (f *fileSrc) Fill(self *base.GstBaseSrc, offset uint64, size uint, buffer *gst.Buffer) gst.FlowReturn {
+func (f *FileSrc) Fill(self *base.GstBaseSrc, offset uint64, size uint, buffer *gst.Buffer) gst.FlowReturn {
 	if !f.state.started || f.state.file == nil {
 		self.ErrorMessage(gst.DomainCore, gst.CoreErrorFailed, "Not started yet", "")
 		return gst.FlowError
@@ -332,16 +332,16 @@ func (f *fileSrc) Fill(self *base.GstBaseSrc, offset uint64, size uint, buffer *
 // URIHandler implementations are the methods required by the GstURIHandler interface.
 
 // GetURI returns the currently configured URI
-func (f *fileSrc) GetURI() string { return fmt.Sprintf("file://%s", f.settings.location) }
+func (f *FileSrc) GetURI() string { return fmt.Sprintf("file://%s", f.settings.location) }
 
 // GetURIType returns the types of URI this element supports.
-func (f *fileSrc) GetURIType() gst.URIType { return gst.URISource }
+func (f *FileSrc) GetURIType() gst.URIType { return gst.URISource }
 
 // GetProtocols returns the protcols this element supports.
-func (f *fileSrc) GetProtocols() []string { return []string{"file"} }
+func (f *FileSrc) GetProtocols() []string { return []string{"file"} }
 
 // SetURI should set the URI that this element is working on.
-func (f *fileSrc) SetURI(uri string) (bool, error) {
+func (f *FileSrc) SetURI(uri string) (bool, error) {
 	if uri == "file://" {
 		return true, nil
 	}
diff --git a/examples/toc/main.go b/examples/toc/main.go
index b4b5fa4..a1c93be 100644
--- a/examples/toc/main.go
+++ b/examples/toc/main.go
@@ -26,7 +26,7 @@ func tagsetter(mainLoop *glib.MainLoop) error {
 	gst.Init(nil)
 
 	if len(os.Args) < 2 {
-		return errors.New("Usage: toc <file>")
+		return errors.New("usage: toc <file>")
 	}
 
 	pipeline, err := gst.NewPipeline("")
@@ -99,7 +99,6 @@ func tagsetter(mainLoop *glib.MainLoop) error {
 		// End of stream
 		case gst.MessageEOS:
 			msg.Unref()
-			break
 
 			// Errors from any elements
 		case gst.MessageError:
diff --git a/gst/app/gst_app_sink.go b/gst/app/gst_app_sink.go
index 5329846..baee8c2 100644
--- a/gst/app/gst_app_sink.go
+++ b/gst/app/gst_app_sink.go
@@ -35,7 +35,7 @@ type SinkCallbacks struct {
 }
 
 // ErrEOS represents that the stream has ended.
-var ErrEOS = errors.New("Pipeline has reached end-of-stream")
+var ErrEOS = errors.New("pipeline has reached end-of-stream")
 
 // Sink wraps an Element made with the appsink plugin with additional methods for pulling samples.
 type Sink struct{ *base.GstBaseSink }
diff --git a/gst/c_util.go b/gst/c_util.go
index 084a836..5b3810b 100644
--- a/gst/c_util.go
+++ b/gst/c_util.go
@@ -31,9 +31,8 @@ func gboolean(b bool) C.gboolean {
 
 // gdateToTime converts a GDate to a time object.
 func gdateToTime(gdate *C.GDate) time.Time {
-	tm := time.Time{}
-	tm.AddDate(int(C.g_date_get_year(gdate)), int(C.g_date_get_month(gdate)), int(C.g_date_get_day(gdate)))
-	return tm
+	// should this really be local time?
+	return time.Date(int(C.g_date_get_year(gdate)), time.Month(C.g_date_get_month(gdate)), int(C.g_date_get_day(gdate)), 0, 0, 0, 0, time.Local)
 }
 
 // gstDateTimeToTime converts a GstDateTime to a time object. If the datetime object could not be parsed,
diff --git a/gst/gst_bin.go b/gst/gst_bin.go
index d1457c3..3f5141c 100644
--- a/gst/gst_bin.go
+++ b/gst/gst_bin.go
@@ -128,7 +128,7 @@ func (b *Bin) GetElementByName(name string) (*Element, error) {
 	defer C.free(unsafe.Pointer(cName))
 	elem := C.gst_bin_get_by_name((*C.GstBin)(b.Instance()), (*C.gchar)(cName))
 	if elem == nil {
-		return nil, fmt.Errorf("Could not find element with name %s", name)
+		return nil, fmt.Errorf("could not find element with name %s", name)
 	}
 	return wrapElement(glib.TransferFull(unsafe.Pointer(elem))), nil
 }
@@ -140,7 +140,7 @@ func (b *Bin) GetElementByNameRecursive(name string) (*Element, error) {
 	defer C.free(unsafe.Pointer(cName))
 	elem := C.gst_bin_get_by_name_recurse_up((*C.GstBin)(b.Instance()), (*C.gchar)(cName))
 	if elem == nil {
-		return nil, fmt.Errorf("Could not find element with name %s", name)
+		return nil, fmt.Errorf("could not find element with name %s", name)
 	}
 	return wrapElement(glib.TransferFull(unsafe.Pointer(elem))), nil
 }
@@ -185,7 +185,7 @@ func (b *Bin) GetElementsSorted() ([]*Element, error) {
 func (b *Bin) GetByInterface(iface glib.Interface) (*Element, error) {
 	elem := C.gst_bin_get_by_interface(b.Instance(), C.GType(iface.Type()))
 	if elem == nil {
-		return nil, fmt.Errorf("Could not find any elements implementing %s", iface.Type().Name())
+		return nil, fmt.Errorf("could not find any elements implementing %s", iface.Type().Name())
 	}
 	return wrapElement(glib.TransferFull(unsafe.Pointer(elem))), nil
 }
@@ -210,7 +210,7 @@ func (b *Bin) GetAllByInterface(iface glib.Interface) ([]*Element, error) {
 // Add adds an element to the bin.
 func (b *Bin) Add(elem *Element) error {
 	if ok := C.gst_bin_add((*C.GstBin)(b.Instance()), (*C.GstElement)(elem.Instance())); !gobool(ok) {
-		return fmt.Errorf("Failed to add element to pipeline: %s", elem.GetName())
+		return fmt.Errorf("failed to add element to pipeline: %s", elem.GetName())
 	}
 	return nil
 }
@@ -228,7 +228,7 @@ func (b *Bin) AddMany(elems ...*Element) error {
 // Remove removes an element from the Bin.
 func (b *Bin) Remove(elem *Element) error {
 	if ok := C.gst_bin_remove((*C.GstBin)(b.Instance()), (*C.GstElement)(elem.Instance())); !gobool(ok) {
-		return fmt.Errorf("Failed to remove element from pipeline: %s", elem.GetName())
+		return fmt.Errorf("failed to remove element from pipeline: %s", elem.GetName())
 	}
 	return nil
 }
@@ -340,7 +340,7 @@ func iteratorToElementSlice(iterator *C.GstIterator) ([]*Element, error) {
 			elems = append(elems, wrapElement(glib.TransferNone(unsafe.Pointer(cElem))))
 			C.g_value_unset((*C.GValue)(gval))
 		default:
-			return nil, errors.New("Element iterator failed")
+			return nil, errors.New("element iterator failed")
 		}
 	}
 }
diff --git a/gst/gst_buffer.go b/gst/gst_buffer.go
index 351011d..b28b94b 100644
--- a/gst/gst_buffer.go
+++ b/gst/gst_buffer.go
@@ -22,7 +22,6 @@ import "C"
 import (
 	"bytes"
 	"io"
-	"io/ioutil"
 	"runtime"
 	"unsafe"
 
@@ -104,7 +103,7 @@ func NewBufferFromBytes(b []byte) *Buffer {
 
 // NewBufferFromReader returns a new buffer from the given io.Reader.
 func NewBufferFromReader(rdr io.Reader) (*Buffer, error) {
-	out, err := ioutil.ReadAll(rdr)
+	out, err := io.ReadAll(rdr)
 	if err != nil {
 		return nil, err
 	}
diff --git a/gst/gst_device.go b/gst/gst_device.go
index fc9dc2c..903e85f 100644
--- a/gst/gst_device.go
+++ b/gst/gst_device.go
@@ -91,7 +91,7 @@ func (d *Device) HasClasses(classes []string) bool {
 // while in the PLAYING state.
 func (d *Device) ReconfigureElement(elem *Element) error {
 	if ok := gobool(C.gst_device_reconfigure_element(d.Instance(), elem.Instance())); !ok {
-		return fmt.Errorf("Failed to reconfigure element %s", elem.GetName())
+		return fmt.Errorf("failed to reconfigure element %s", elem.GetName())
 	}
 	return nil
 }
diff --git a/gst/gst_element.go b/gst/gst_element.go
index 07a8d67..a83b299 100644
--- a/gst/gst_element.go
+++ b/gst/gst_element.go
@@ -365,7 +365,7 @@ func (e *Element) IsURIHandler() bool {
 // Link wraps gst_element_link and links this element to the given one.
 func (e *Element) Link(elem *Element) error {
 	if ok := C.gst_element_link((*C.GstElement)(e.Instance()), (*C.GstElement)(elem.Instance())); !gobool(ok) {
-		return fmt.Errorf("Failed to link %s to %s", e.GetName(), elem.GetName())
+		return fmt.Errorf("failed to link %s to %s", e.GetName(), elem.GetName())
 	}
 	return nil
 }
@@ -379,12 +379,12 @@ func (e *Element) Unlink(elem *Element) {
 func (e *Element) LinkFiltered(elem *Element, filter *Caps) error {
 	if filter == nil {
 		if ok := C.gst_element_link_filtered(e.Instance(), elem.Instance(), nil); !gobool(ok) {
-			return fmt.Errorf("Failed to link %s to %s with provided caps", e.GetName(), elem.GetName())
+			return fmt.Errorf("failed to link %s to %s with provided caps", e.GetName(), elem.GetName())
 		}
 		return nil
 	}
 	if ok := C.gst_element_link_filtered(e.Instance(), elem.Instance(), filter.Instance()); !gobool(ok) {
-		return fmt.Errorf("Failed to link %s to %s with provided caps", e.GetName(), elem.GetName())
+		return fmt.Errorf("failed to link %s to %s with provided caps", e.GetName(), elem.GetName())
 	}
 	return nil
 }
@@ -454,7 +454,7 @@ func (e *Element) SendEvent(ev *Event) bool {
 func (e *Element) SetState(state State) error {
 	stateRet := C.gst_element_set_state((*C.GstElement)(e.Instance()), C.GstState(state))
 	if stateRet == C.GST_STATE_CHANGE_FAILURE {
-		return fmt.Errorf("Failed to change state to %s", state.String())
+		return fmt.Errorf("failed to change state to %s", state.String())
 	}
 	return nil
 }
diff --git a/gst/gst_mapinfo.go b/gst/gst_mapinfo.go
index 494192d..189cac2 100644
--- a/gst/gst_mapinfo.go
+++ b/gst/gst_mapinfo.go
@@ -55,7 +55,7 @@ type mapInfoWriter struct {
 
 func (m *mapInfoWriter) Write(p []byte) (int, error) {
 	if m.wsize+len(p) > int(m.mapInfo.Size()) {
-		return 0, errors.New("Attempt to write more data than allocated to MapInfo")
+		return 0, errors.New("attempt to write more data than allocated to MapInfo")
 	}
 	m.mapInfo.WriteAt(m.wsize, p)
 	m.wsize += len(p)
diff --git a/gst/gst_pad.go b/gst/gst_pad.go
index 7fbd590..451ff02 100644
--- a/gst/gst_pad.go
+++ b/gst/gst_pad.go
@@ -1136,7 +1136,7 @@ func iteratorToPadSlice(iterator *C.GstIterator) ([]*Pad, error) {
 			pads = append(pads, FromGstPadUnsafeNone(unsafe.Pointer(cPad)))
 			C.g_value_unset((*C.GValue)(gval))
 		default:
-			return nil, errors.New("Pad iterator failed")
+			return nil, errors.New("pad iterator failed")
 		}
 	}
 }
diff --git a/gst/gst_pipeline.go b/gst/gst_pipeline.go
index 179bd12..8d0d81f 100644
--- a/gst/gst_pipeline.go
+++ b/gst/gst_pipeline.go
@@ -38,7 +38,7 @@ func NewPipeline(name string) (*Pipeline, error) {
 	}
 	pipeline := C.gst_pipeline_new((*C.gchar)(cChar))
 	if pipeline == nil {
-		return nil, errors.New("Could not create new pipeline")
+		return nil, errors.New("could not create new pipeline")
 	}
 	return FromGstPipelineUnsafeNone(unsafe.Pointer(pipeline)), nil
 }
@@ -46,7 +46,7 @@ func NewPipeline(name string) (*Pipeline, error) {
 // NewPipelineFromString creates a new gstreamer pipeline from the given launch string.
 func NewPipelineFromString(launchv string) (*Pipeline, error) {
 	if len(strings.Split(launchv, "!")) < 2 {
-		return nil, fmt.Errorf("Given string is too short for a pipeline: %s", launchv)
+		return nil, fmt.Errorf("given string is too short for a pipeline: %s", launchv)
 	}
 	cLaunchv := C.CString(launchv)
 	defer C.free(unsafe.Pointer(cLaunchv))
diff --git a/gst/gst_registry.go b/gst/gst_registry.go
index 46399c4..ca047c9 100644
--- a/gst/gst_registry.go
+++ b/gst/gst_registry.go
@@ -38,7 +38,7 @@ func (r *Registry) FindPlugin(name string) (*Plugin, error) {
 	defer C.free(unsafe.Pointer(cName))
 	plugin := C.gst_registry_find_plugin((*C.GstRegistry)(r.Instance()), (*C.gchar)(cName))
 	if plugin == nil {
-		return nil, fmt.Errorf("No plugin named %s found", name)
+		return nil, fmt.Errorf("no plugin named %s found", name)
 	}
 	return FromGstPluginUnsafeFull(unsafe.Pointer(plugin)), nil
 }
@@ -49,7 +49,7 @@ func (r *Registry) LookupFeature(name string) (*PluginFeature, error) {
 	defer C.free(unsafe.Pointer(cName))
 	feat := C.gst_registry_lookup_feature((*C.GstRegistry)(r.Instance()), (*C.gchar)(cName))
 	if feat == nil {
-		return nil, fmt.Errorf("No feature named %s found", name)
+		return nil, fmt.Errorf("no feature named %s found", name)
 	}
 	return wrapPluginFeature(glib.TransferFull(unsafe.Pointer(feat))), nil
 }
diff --git a/gst/gst_stream_collection.go b/gst/gst_stream_collection.go
index 71aa135..387109c 100644
--- a/gst/gst_stream_collection.go
+++ b/gst/gst_stream_collection.go
@@ -40,7 +40,7 @@ func (s *StreamCollection) Instance() *C.GstStreamCollection {
 // AddStream adds the given stream to this collection.
 func (s *StreamCollection) AddStream(stream *Stream) error {
 	if ok := gobool(C.gst_stream_collection_add_stream(s.Instance(), stream.Instance())); !ok {
-		return fmt.Errorf("Failed to add stream %s to collection", stream.StreamID())
+		return fmt.Errorf("failed to add stream %s to collection", stream.StreamID())
 	}
 	return nil
 }
diff --git a/gst/gst_structure.go b/gst/gst_structure.go
index 58e89d8..c5535e7 100644
--- a/gst/gst_structure.go
+++ b/gst/gst_structure.go
@@ -76,7 +76,7 @@ func FromGstStructureUnsafe(st unsafe.Pointer) *Structure {
 func (s *Structure) UnmarshalInto(data interface{}) error {
 	rv := reflect.ValueOf(data)
 	if rv.Kind() != reflect.Ptr || rv.IsNil() {
-		return errors.New("Data is invalid (nil or non-pointer)")
+		return errors.New("data is invalid (nil or non-pointer)")
 	}
 
 	val := reflect.ValueOf(data).Elem()
@@ -134,7 +134,7 @@ func (s *Structure) GetValue(key string) (interface{}, error) {
 	defer C.free(unsafe.Pointer(cKey))
 	gVal := C.gst_structure_get_value(s.Instance(), cKey)
 	if gVal == nil {
-		return nil, fmt.Errorf("No value exists at %s", key)
+		return nil, fmt.Errorf("no value exists at %s", key)
 	}
 	return glib.ValueFromNative(unsafe.Pointer(gVal)).GoValue()
 }