feat: build without libopusfile using go build tag

This patch introduces a new build tag `nolibopusfile` that conditionally
compiles out the code that imports `libopusfile`. This enables a static
binary build on Alpine Linux, which doesn’t have a static `libopusfile`.

Tests still work:

```sh
go test -tags nolibopusfile ./...
go test ./...
```

We could also have moved all libopusfile related code (i.e. Stream) into
a separate sub-package, but that would break backwards compatibility.
This feature is too unpopular to justify introducing a new major
version.

See also: https://github.com/hraban/opus/pull/24

diff --git a/README.md b/README.md
index 28a67f8ef504ef24367cb04b9c48fc9cdb4f0187..c0dddf8573b4b82cb2a073aa21a384ddbc184123 100644 (file)
--- a/README.md
+++ b/README.md
@@ -117,7 +117,7 @@ Note regarding Forward Error Correction (FEC):
 > Note also that in order to use this feature the encoder needs to be configured
 > with `SetInBandFEC(true)` and `SetPacketLossPerc(x)` options.
 
-### Streams (and files)
+### Streams (and Files)
 
 To decode a .opus file (or .ogg with Opus data), or to decode a "Opus stream"
 (which is a Ogg stream with Opus data), use the `Stream` interface. It wraps an
@@ -162,7 +162,7 @@ https://www.opus-codec.org/docs/opus_api-1.1.3/
 
 For more examples, see the `_test.go` files.
 
-## Build & installation
+## Build & Installation
 
 This package requires libopus and libopusfile development packages to be
 installed on your system. These are available on Debian based systems from
@@ -180,6 +180,25 @@ Mac:
 brew install pkg-config opus opusfile
 ```
 
+### Building Without `libopusfile`
+
+This package can be built without `libopusfile` by using the build tag `nolibopusfile`.
+This enables the compilation of statically-linked binaries with no external
+dependencies on operating systems without a static `libopusfile`, such as
+[Alpine Linux](https://pkgs.alpinelinux.org/contents?branch=edge&name=opusfile-dev&arch=x86_64&repo=main).
+
+**Note:** this will disable all file and `Stream` APIs.
+
+To enable this feature, add `-tags nolibopusfile` to your `go build` or `go test` commands:
+
+```sh
+# Build
+go build -tags nolibopusfile ...
+
+# Test
+go test -tags nolibopusfile ./...
+```
+
 ### Using in Docker
 
 If your Dockerized app has this library as a dependency (directly or

diff --git a/callbacks.c b/callbacks.c
index d966f8c4e1bc916e78e76484542ece427651cc73..14ad2bd60d74c073ef94184b2ee13df6b7ddc637 100644 (file)
--- a/callbacks.c
+++ b/callbacks.c
@@ -1,3 +1,5 @@
+// +build !nolibopusfile
+
 // Copyright © Go Opus Authors (see AUTHORS file)
 //
 // License for use of this code is detailed in the LICENSE file

diff --git a/errors.go b/errors.go
index ea1e56584e516c2a2f05c4299ba893bc39b82025..8e161ad6e491a0f8a2ba4d132826d4c0495be00b 100644 (file)
--- a/errors.go
+++ b/errors.go
@@ -9,9 +9,8 @@ import (
 )
 
 /*
-#cgo pkg-config: opus opusfile
+#cgo pkg-config: opus
 #include <opus.h>
-#include <opusfile.h>
 */
 import "C"
 
@@ -35,64 +34,3 @@ const (
 func (e Error) Error() string {
        return fmt.Sprintf("opus: %s", C.GoString(C.opus_strerror(C.int(e))))
 }
-
-type StreamError int
-
-var _ error = StreamError(0)
-
-// Libopusfile errors. The names are copied verbatim from the libopusfile
-// library.
-const (
-       ErrStreamFalse        = StreamError(C.OP_FALSE)
-       ErrStreamEOF          = StreamError(C.OP_EOF)
-       ErrStreamHole         = StreamError(C.OP_HOLE)
-       ErrStreamRead         = StreamError(C.OP_EREAD)
-       ErrStreamFault        = StreamError(C.OP_EFAULT)
-       ErrStreamImpl         = StreamError(C.OP_EIMPL)
-       ErrStreamInval        = StreamError(C.OP_EINVAL)
-       ErrStreamNotFormat    = StreamError(C.OP_ENOTFORMAT)
-       ErrStreamBadHeader    = StreamError(C.OP_EBADHEADER)
-       ErrStreamVersion      = StreamError(C.OP_EVERSION)
-       ErrStreamNotAudio     = StreamError(C.OP_ENOTAUDIO)
-       ErrStreamBadPacked    = StreamError(C.OP_EBADPACKET)
-       ErrStreamBadLink      = StreamError(C.OP_EBADLINK)
-       ErrStreamNoSeek       = StreamError(C.OP_ENOSEEK)
-       ErrStreamBadTimestamp = StreamError(C.OP_EBADTIMESTAMP)
-)
-
-func (i StreamError) Error() string {
-       switch i {
-       case ErrStreamFalse:
-               return "OP_FALSE"
-       case ErrStreamEOF:
-               return "OP_EOF"
-       case ErrStreamHole:
-               return "OP_HOLE"
-       case ErrStreamRead:
-               return "OP_EREAD"
-       case ErrStreamFault:
-               return "OP_EFAULT"
-       case ErrStreamImpl:
-               return "OP_EIMPL"
-       case ErrStreamInval:
-               return "OP_EINVAL"
-       case ErrStreamNotFormat:
-               return "OP_ENOTFORMAT"
-       case ErrStreamBadHeader:
-               return "OP_EBADHEADER"
-       case ErrStreamVersion:
-               return "OP_EVERSION"
-       case ErrStreamNotAudio:
-               return "OP_ENOTAUDIO"
-       case ErrStreamBadPacked:
-               return "OP_EBADPACKET"
-       case ErrStreamBadLink:
-               return "OP_EBADLINK"
-       case ErrStreamNoSeek:
-               return "OP_ENOSEEK"
-       case ErrStreamBadTimestamp:
-               return "OP_EBADTIMESTAMP"
-       default:
-               return "libopusfile error: %d (unknown code)"
-       }
-}

diff --git a/stream.go b/stream.go
index 46e30fa56e92db4b9a3c0750a7d51777a506faa4..323da2d704691947d159a17f4d9a416c3cdb3d8a 100644 (file)
--- a/stream.go
+++ b/stream.go
@@ -2,6 +2,8 @@
 //
 // License for use of this code is detailed in the LICENSE file
 
+// +build !nolibopusfile
+
 package opus
 
 import (

diff --git a/stream_errors.go b/stream_errors.go
new file mode 100644 (file)
index 0000000..f1b5cba
--- /dev/null
+++ b/stream_errors.go
@@ -0,0 +1,75 @@
+// Copyright © 2015-2017 Go Opus Authors (see AUTHORS file)
+//
+// License for use of this code is detailed in the LICENSE file
+
+// +build !nolibopusfile
+
+package opus
+
+/*
+#cgo pkg-config: opusfile
+#include <opusfile.h>
+*/
+import "C"
+
+// StreamError represents an error from libopusfile.
+type StreamError int
+
+var _ error = StreamError(0)
+
+// Libopusfile errors. The names are copied verbatim from the libopusfile
+// library.
+const (
+       ErrStreamFalse        = StreamError(C.OP_FALSE)
+       ErrStreamEOF          = StreamError(C.OP_EOF)
+       ErrStreamHole         = StreamError(C.OP_HOLE)
+       ErrStreamRead         = StreamError(C.OP_EREAD)
+       ErrStreamFault        = StreamError(C.OP_EFAULT)
+       ErrStreamImpl         = StreamError(C.OP_EIMPL)
+       ErrStreamInval        = StreamError(C.OP_EINVAL)
+       ErrStreamNotFormat    = StreamError(C.OP_ENOTFORMAT)
+       ErrStreamBadHeader    = StreamError(C.OP_EBADHEADER)
+       ErrStreamVersion      = StreamError(C.OP_EVERSION)
+       ErrStreamNotAudio     = StreamError(C.OP_ENOTAUDIO)
+       ErrStreamBadPacked    = StreamError(C.OP_EBADPACKET)
+       ErrStreamBadLink      = StreamError(C.OP_EBADLINK)
+       ErrStreamNoSeek       = StreamError(C.OP_ENOSEEK)
+       ErrStreamBadTimestamp = StreamError(C.OP_EBADTIMESTAMP)
+)
+
+func (i StreamError) Error() string {
+       switch i {
+       case ErrStreamFalse:
+               return "OP_FALSE"
+       case ErrStreamEOF:
+               return "OP_EOF"
+       case ErrStreamHole:
+               return "OP_HOLE"
+       case ErrStreamRead:
+               return "OP_EREAD"
+       case ErrStreamFault:
+               return "OP_EFAULT"
+       case ErrStreamImpl:
+               return "OP_EIMPL"
+       case ErrStreamInval:
+               return "OP_EINVAL"
+       case ErrStreamNotFormat:
+               return "OP_ENOTFORMAT"
+       case ErrStreamBadHeader:
+               return "OP_EBADHEADER"
+       case ErrStreamVersion:
+               return "OP_EVERSION"
+       case ErrStreamNotAudio:
+               return "OP_ENOTAUDIO"
+       case ErrStreamBadPacked:
+               return "OP_EBADPACKET"
+       case ErrStreamBadLink:
+               return "OP_EBADLINK"
+       case ErrStreamNoSeek:
+               return "OP_ENOSEEK"
+       case ErrStreamBadTimestamp:
+               return "OP_EBADTIMESTAMP"
+       default:
+               return "libopusfile error: %d (unknown code)"
+       }
+}

diff --git a/stream_test.go b/stream_test.go
index fa4293fdd8c18ff76d0f339abe09929701581077..c6eb4fe9b9e17de7f90eb9998a778551643b8e39 100644 (file)
--- a/stream_test.go
+++ b/stream_test.go
@@ -2,6 +2,8 @@
 //
 // License for use of this code is detailed in the LICENSE file
 
+// +build !nolibopusfile
+
 package opus
 
 import (

diff --git a/streams_map.go b/streams_map.go
index 588718b42c322fb22d624fedda3d90f02ec7b600..944ab3971200952dd3ccacb24ea8c10970bbba23 100644 (file)
--- a/streams_map.go
+++ b/streams_map.go
@@ -2,6 +2,8 @@
 //
 // License for use of this code is detailed in the LICENSE file
 
+// +build !nolibopusfile
+
 package opus
 
 import (