input_stream: forward-declare the struct

Hide the definition from C code, to prepare the transition to C++.

36 files changed, 266 insertions, 141 deletions

diff --git a/src/DecoderAPI.cxx b/src/DecoderAPI.cxx
index 0e127ec02..56c25e489 100644
--- a/src/DecoderAPI.cxx
+++ b/src/DecoderAPI.cxx
@@ -31,6 +31,7 @@ extern "C" {
 #include "DecoderControl.hxx"
 #include "DecoderInternal.hxx"
 #include "song.h"
+#include "InputStream.hxx"
 
 #include <glib.h>
 
diff --git a/src/DecoderInternal.cxx b/src/DecoderInternal.cxx
index 505d2bc94..af36e1763 100644
--- a/src/DecoderInternal.cxx
+++ b/src/DecoderInternal.cxx
@@ -24,7 +24,6 @@
 #include "MusicBuffer.hxx"
 #include "MusicChunk.hxx"
 #include "tag.h"
-#include "input_stream.h"
 
 #include <assert.h>
 
diff --git a/src/DecoderThread.cxx b/src/DecoderThread.cxx
index b821c6d7a..4b9cdfd81 100644
--- a/src/DecoderThread.cxx
+++ b/src/DecoderThread.cxx
@@ -29,7 +29,7 @@
 #include "fs/Path.hxx"
 #include "decoder_api.h"
 #include "tag.h"
-#include "input_stream.h"
+#include "InputStream.hxx"
 
 extern "C" {
 #include "decoder_list.h"
diff --git a/src/InputInternal.cxx b/src/InputInternal.cxx
index a5e5ecd59..8fc4fa0a8 100644
--- a/src/InputInternal.cxx
+++ b/src/InputInternal.cxx
@@ -19,7 +19,7 @@
 
 #include "config.h"
 #include "InputInternal.hxx"
-#include "input_stream.h"
+#include "InputStream.hxx"
 
 #include <assert.h>
 
diff --git a/src/InputStream.cxx b/src/InputStream.cxx
index a39af2bd6..e55450d91 100644
--- a/src/InputStream.cxx
+++ b/src/InputStream.cxx
@@ -18,7 +18,7 @@
  */
 
 #include "config.h"
-#include "input_stream.h"
+#include "InputStream.hxx"
 #include "InputRegistry.hxx"
 #include "InputPlugin.hxx"
 #include "input/RewindInputPlugin.hxx"
@@ -118,6 +118,52 @@ input_stream_lock_wait_ready(struct input_stream *is)
 	g_mutex_unlock(is->mutex);
 }
 
+const char *
+input_stream_get_mime_type(const struct input_stream *is)
+{
+	assert(is != NULL);
+	assert(is->ready);
+
+	return is->mime;
+}
+
+void
+input_stream_override_mime_type(struct input_stream *is, const char *mime)
+{
+	assert(is != NULL);
+	assert(is->ready);
+
+	g_free(is->mime);
+	is->mime = g_strdup(mime);
+}
+
+goffset
+input_stream_get_size(const struct input_stream *is)
+{
+	assert(is != NULL);
+	assert(is->ready);
+
+	return is->size;
+}
+
+goffset
+input_stream_get_offset(const struct input_stream *is)
+{
+	assert(is != NULL);
+	assert(is->ready);
+
+	return is->offset;
+}
+
+bool
+input_stream_is_seekable(const struct input_stream *is)
+{
+	assert(is != NULL);
+	assert(is->ready);
+
+	return is->seekable;
+}
+
 bool
 input_stream_cheap_seeking(const struct input_stream *is)
 {
diff --git a/src/InputStream.hxx b/src/InputStream.hxx
new file mode 100644
index 000000000..8a82888f0
--- /dev/null
+++ b/src/InputStream.hxx
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_INPUT_STREAM_HXX
+#define MPD_INPUT_STREAM_HXX
+
+#include "input_stream.h"
+#include "check.h"
+#include "gcc.h"
+
+#include <glib.h>
+
+struct input_stream {
+	/**
+	 * the plugin which implements this input stream
+	 */
+	const struct input_plugin *plugin;
+
+	/**
+	 * The absolute URI which was used to open this stream.  May
+	 * be NULL if this is unknown.
+	 */
+	char *uri;
+
+	/**
+	 * A mutex that protects the mutable attributes of this object
+	 * and its implementation.  It must be locked before calling
+	 * any of the public methods.
+	 *
+	 * This object is allocated by the client, and the client is
+	 * responsible for freeing it.
+	 */
+	GMutex *mutex;
+
+	/**
+	 * A cond that gets signalled when the state of this object
+	 * changes from the I/O thread.  The client of this object may
+	 * wait on it.  Optional, may be NULL.
+	 *
+	 * This object is allocated by the client, and the client is
+	 * responsible for freeing it.
+	 */
+	GCond *cond;
+
+	/**
+	 * indicates whether the stream is ready for reading and
+	 * whether the other attributes in this struct are valid
+	 */
+	bool ready;
+
+	/**
+	 * if true, then the stream is fully seekable
+	 */
+	bool seekable;
+
+	/**
+	 * the size of the resource, or -1 if unknown
+	 */
+	goffset size;
+
+	/**
+	 * the current offset within the stream
+	 */
+	goffset offset;
+
+	/**
+	 * the MIME content type of the resource, or NULL if unknown
+	 */
+	char *mime;
+};
+
+gcc_nonnull(1)
+static inline void
+input_stream_lock(struct input_stream *is)
+{
+	g_mutex_lock(is->mutex);
+}
+
+gcc_nonnull(1)
+static inline void
+input_stream_unlock(struct input_stream *is)
+{
+	g_mutex_unlock(is->mutex);
+}
+
+#endif
diff --git a/src/PlaylistRegistry.cxx b/src/PlaylistRegistry.cxx
index f919f388b..1e9edd443 100644
--- a/src/PlaylistRegistry.cxx
+++ b/src/PlaylistRegistry.cxx
@@ -233,19 +233,19 @@ playlist_list_open_stream_mime2(struct input_stream *is, const char *mime)
 }
 
 static struct playlist_provider *
-playlist_list_open_stream_mime(struct input_stream *is)
+playlist_list_open_stream_mime(struct input_stream *is, const char *full_mime)
 {
-	assert(is->mime != NULL);
+	assert(full_mime != NULL);
 
-	const char *semicolon = strchr(is->mime, ';');
+	const char *semicolon = strchr(full_mime, ';');
 	if (semicolon == NULL)
-		return playlist_list_open_stream_mime2(is, is->mime);
+		return playlist_list_open_stream_mime2(is, full_mime);
 
-	if (semicolon == is->mime)
+	if (semicolon == full_mime)
 		return NULL;
 
 	/* probe only the portion before the semicolon*/
-	char *mime = g_strndup(is->mime, semicolon - is->mime);
+	char *mime = g_strndup(full_mime, semicolon - full_mime);
 	struct playlist_provider *playlist =
 		playlist_list_open_stream_mime2(is, mime);
 	g_free(mime);
@@ -285,8 +285,9 @@ playlist_list_open_stream(struct input_stream *is, const char *uri)
 
 	input_stream_lock_wait_ready(is);
 
-	if (is->mime != NULL) {
-		playlist = playlist_list_open_stream_mime(is);
+	const char *const mime = input_stream_get_mime_type(is);
+	if (mime != NULL) {
+		playlist = playlist_list_open_stream_mime(is, mime);
 		if (playlist != NULL)
 			return playlist;
 	}
diff --git a/src/archive/Bzip2ArchivePlugin.cxx b/src/archive/Bzip2ArchivePlugin.cxx
index 1e7c0c80e..c8d8f3977 100644
--- a/src/archive/Bzip2ArchivePlugin.cxx
+++ b/src/archive/Bzip2ArchivePlugin.cxx
@@ -26,6 +26,7 @@
 #include "ArchiveInternal.hxx"
 #include "ArchivePlugin.hxx"
 #include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 #include "refcount.h"
 
diff --git a/src/archive/Iso9660ArchivePlugin.cxx b/src/archive/Iso9660ArchivePlugin.cxx
index a3bf600a0..d081fe330 100644
--- a/src/archive/Iso9660ArchivePlugin.cxx
+++ b/src/archive/Iso9660ArchivePlugin.cxx
@@ -26,6 +26,7 @@
 #include "ArchiveInternal.hxx"
 #include "ArchivePlugin.hxx"
 #include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 #include "refcount.h"
 
diff --git a/src/archive/ZzipArchivePlugin.cxx b/src/archive/ZzipArchivePlugin.cxx
index ea6ec4e75..28c3f46a4 100644
--- a/src/archive/ZzipArchivePlugin.cxx
+++ b/src/archive/ZzipArchivePlugin.cxx
@@ -26,6 +26,7 @@
 #include "ArchiveInternal.hxx"
 #include "ArchivePlugin.hxx"
 #include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 #include "refcount.h"
 
diff --git a/src/decoder/FLACIOHandle.hxx b/src/decoder/FLACIOHandle.hxx
index 0c2c24770..505d2db1a 100644
--- a/src/decoder/FLACIOHandle.hxx
+++ b/src/decoder/FLACIOHandle.hxx
@@ -21,7 +21,7 @@
 #define MPD_FLAC_IO_HANDLE_HXX
 
 #include "gcc.h"
-#include "input_stream.h"
+#include "InputStream.hxx"
 
 #include <FLAC/callback.h>
 
diff --git a/src/decoder/FLACInput.cxx b/src/decoder/FLACInput.cxx
index 99f321cdd..ba0a86ce8 100644
--- a/src/decoder/FLACInput.cxx
+++ b/src/decoder/FLACInput.cxx
@@ -21,7 +21,7 @@
 #include "FLACInput.hxx"
 #include "decoder_api.h"
 #include "gcc.h"
-#include "input_stream.h"
+#include "InputStream.hxx"
 
 FLAC__StreamDecoderReadStatus
 FLACInput::Read(FLAC__byte buffer[], size_t *bytes)
diff --git a/src/decoder/FfmpegDecoderPlugin.cxx b/src/decoder/FfmpegDecoderPlugin.cxx
index ac2883305..e89f35ef6 100644
--- a/src/decoder/FfmpegDecoderPlugin.cxx
+++ b/src/decoder/FfmpegDecoderPlugin.cxx
@@ -25,6 +25,7 @@
 #include "decoder_api.h"
 #include "FfmpegMetaData.hxx"
 #include "tag_handler.h"
+#include "InputStream.hxx"
 
 extern "C" {
 #include "audio_check.h"
diff --git a/src/decoder/OpusDecoderPlugin.cxx b/src/decoder/OpusDecoderPlugin.cxx
index f0c0a442d..8be95ab2e 100644
--- a/src/decoder/OpusDecoderPlugin.cxx
+++ b/src/decoder/OpusDecoderPlugin.cxx
@@ -28,6 +28,7 @@
 #include "OggCodec.hxx"
 #include "audio_check.h"
 #include "tag_handler.h"
+#include "InputStream.hxx"
 
 #include <opus.h>
 #include <ogg/ogg.h>
diff --git a/src/decoder/VorbisDecoderPlugin.cxx b/src/decoder/VorbisDecoderPlugin.cxx
index 01a558def..488786ed8 100644
--- a/src/decoder/VorbisDecoderPlugin.cxx
+++ b/src/decoder/VorbisDecoderPlugin.cxx
@@ -21,6 +21,7 @@
 #include "VorbisDecoderPlugin.h"
 #include "VorbisComments.hxx"
 #include "decoder_api.h"
+#include "InputStream.hxx"
 #include "OggCodec.hxx"
 
 extern "C" {
diff --git a/src/decoder/WavpackDecoderPlugin.cxx b/src/decoder/WavpackDecoderPlugin.cxx
index fdd910c84..aeecf6415 100644
--- a/src/decoder/WavpackDecoderPlugin.cxx
+++ b/src/decoder/WavpackDecoderPlugin.cxx
@@ -20,6 +20,7 @@
 #include "config.h"
 #include "WavpackDecoderPlugin.hxx"
 #include "decoder_api.h"
+#include "InputStream.hxx"
 
 extern "C" {
 #include "audio_check.h"
diff --git a/src/decoder/audiofile_decoder_plugin.c b/src/decoder/audiofile_decoder_plugin.c
index b344795e7..d2ceee8ae 100644
--- a/src/decoder/audiofile_decoder_plugin.c
+++ b/src/decoder/audiofile_decoder_plugin.c
@@ -69,14 +69,14 @@ static AFfileoffset
 audiofile_file_length(AFvirtualfile *vfile)
 {
 	struct input_stream *is = (struct input_stream *) vfile->closure;
-	return is->size;
+	return input_stream_get_size(is);
 }
 
 static AFfileoffset
 audiofile_file_tell(AFvirtualfile *vfile)
 {
 	struct input_stream *is = (struct input_stream *) vfile->closure;
-	return is->offset;
+	return input_stream_get_offset(is);
 }
 
 static void
@@ -93,7 +93,7 @@ audiofile_file_seek(AFvirtualfile *vfile, AFfileoffset offset, int is_relative)
 	struct input_stream *is = (struct input_stream *) vfile->closure;
 	int whence = (is_relative ? SEEK_CUR : SEEK_SET);
 	if (input_stream_lock_seek(is, offset, whence, NULL)) {
-		return is->offset;
+		return input_stream_get_offset(is);
 	} else {
 		return -1;
 	}
@@ -166,7 +166,7 @@ audiofile_stream_decode(struct decoder *decoder, struct input_stream *is)
 	char chunk[CHUNK_SIZE];
 	enum decoder_command cmd;
 
-	if (!is->seekable) {
+	if (!input_stream_is_seekable(is)) {
 		g_warning("not seekable");
 		return;
 	}
@@ -194,7 +194,7 @@ audiofile_stream_decode(struct decoder *decoder, struct input_stream *is)
 
 	total_time = ((float)frame_count / (float)audio_format.sample_rate);
 
-	bit_rate = (uint16_t)(is->size * 8.0 / total_time / 1000.0 + 0.5);
+	bit_rate = (uint16_t)(input_stream_get_size(is) * 8.0 / total_time / 1000.0 + 0.5);
 
 	fs = (int)afGetVirtualFrameSize(af_fp, AF_DEFAULT_TRACK, 1);
 
diff --git a/src/decoder/dsdiff_decoder_plugin.c b/src/decoder/dsdiff_decoder_plugin.c
index 4e21e91de..44d12d899 100644
--- a/src/decoder/dsdiff_decoder_plugin.c
+++ b/src/decoder/dsdiff_decoder_plugin.c
@@ -128,12 +128,12 @@ dsdiff_read_prop_snd(struct decoder *decoder, struct input_stream *is,
 		     goffset end_offset)
 {
 	struct dsdiff_chunk_header header;
-	while ((goffset)(is->offset + sizeof(header)) <= end_offset) {
+	while ((goffset)(input_stream_get_offset(is) + sizeof(header)) <= end_offset) {
 		if (!dsdiff_read_chunk_header(decoder, is, &header))
 			return false;
 
-		goffset chunk_end_offset =
-			is->offset + dsdiff_chunk_size(&header);
+		goffset chunk_end_offset = input_stream_get_offset(is)
+			+ dsdiff_chunk_size(&header);
 		if (chunk_end_offset > end_offset)
 			return false;
 
@@ -174,7 +174,7 @@ dsdiff_read_prop_snd(struct decoder *decoder, struct input_stream *is,
 		}
 	}
 
-	return is->offset == end_offset;
+	return input_stream_get_offset(is) == end_offset;
 }
 
 /**
@@ -186,7 +186,7 @@ dsdiff_read_prop(struct decoder *decoder, struct input_stream *is,
 		 const struct dsdiff_chunk_header *prop_header)
 {
 	uint64_t prop_size = dsdiff_chunk_size(prop_header);
-	goffset end_offset = is->offset + prop_size;
+	goffset end_offset = input_stream_get_offset(is) + prop_size;
 
 	struct dsdlib_id prop_id;
 	if (prop_size < sizeof(prop_id) ||
@@ -261,8 +261,8 @@ dsdiff_read_metadata_extra(struct decoder *decoder, struct input_stream *is,
 	/* Now process all the remaining chunk headers in the stream
 	   and record their position and size */
 
-	while ( is->offset < is->size )
-	{
+	const goffset size = input_stream_get_size(is);
+	while (input_stream_get_offset(is) < size) {
 		uint64_t chunk_size = dsdiff_chunk_size(chunk_header);
 
 		/* DIIN chunk, is directly followed by other chunks  */
@@ -272,19 +272,19 @@ dsdiff_read_metadata_extra(struct decoder *decoder, struct input_stream *is,
 		/* DIAR chunk - DSDIFF native tag for Artist */
 		if (dsdlib_id_equals(&chunk_header->id, "DIAR")) {
 			chunk_size = dsdiff_chunk_size(chunk_header);
-			metadata->diar_offset = is->offset;
+			metadata->diar_offset = input_stream_get_offset(is);
 		}
 
 		/* DITI chunk - DSDIFF native tag for Title */
 		if (dsdlib_id_equals(&chunk_header->id, "DITI")) {
 			chunk_size = dsdiff_chunk_size(chunk_header);
-			metadata->diti_offset = is->offset;
+			metadata->diti_offset = input_stream_get_offset(is);
 		}
 #ifdef HAVE_ID3TAG
 		/* 'ID3 ' chunk, offspec. Used by sacdextract */
 		if (dsdlib_id_equals(&chunk_header->id, "ID3 ")) {
 			chunk_size = dsdiff_chunk_size(chunk_header);
-			metadata->id3_offset = is->offset;
+			metadata->id3_offset = input_stream_get_offset(is);
 			metadata->id3_size = chunk_size;
 		}
 #endif
@@ -293,7 +293,7 @@ dsdiff_read_metadata_extra(struct decoder *decoder, struct input_stream *is,
 				break;
 		}
 
-		if ( is->offset < is->size ) {
+		if (input_stream_get_offset(is) < size) {
 			if (!dsdiff_read_chunk_header(decoder, is, chunk_header))
 				return false;
 		}
@@ -355,7 +355,8 @@ dsdiff_read_metadata(struct decoder *decoder, struct input_stream *is,
 			/* ignore unknown chunk */
 			uint64_t chunk_size;
 			chunk_size = dsdiff_chunk_size(chunk_header);
-			goffset chunk_end_offset = is->offset + chunk_size;
+			goffset chunk_end_offset = input_stream_get_offset(is)
+				+ chunk_size;
 
 			if (!dsdlib_skip_to(decoder, is, chunk_end_offset))
 				return false;
diff --git a/src/decoder/dsdlib.c b/src/decoder/dsdlib.c
index c788184e2..d3043fb05 100644
--- a/src/decoder/dsdlib.c
+++ b/src/decoder/dsdlib.c
@@ -64,24 +64,24 @@ bool
 dsdlib_skip_to(struct decoder *decoder, struct input_stream *is,
 	       goffset offset)
 {
-	if (is->seekable)
+	if (input_stream_is_seekable(is))
 		return input_stream_seek(is, offset, SEEK_SET, NULL);
 
-	if (is->offset > offset)
+	if (input_stream_get_offset(is) > offset)
 		return false;
 
 	char buffer[8192];
-	while (is->offset < offset) {
+	while (input_stream_get_offset(is) < offset) {
 		size_t length = sizeof(buffer);
-		if (offset - is->offset < (goffset)length)
-			length = offset - is->offset;
+		if (offset - input_stream_get_offset(is) < (goffset)length)
+			length = offset - input_stream_get_offset(is);
 
 		size_t nbytes = decoder_read(decoder, is, buffer, length);
 		if (nbytes == 0)
 			return false;
 	}
 
-	assert(is->offset == offset);
+	assert(input_stream_get_offset(is) == offset);
 	return true;
 }
 
@@ -97,7 +97,7 @@ dsdlib_skip(struct decoder *decoder, struct input_stream *is,
 	if (delta == 0)
 		return true;
 
-	if (is->seekable)
+	if (input_stream_is_seekable(is))
 		return input_stream_seek(is, delta, SEEK_CUR, NULL);
 
 	char buffer[8192];
@@ -139,10 +139,12 @@ dsdlib_tag_id3(struct input_stream *is,
 	id3_length_t count;
 
 	/* Prevent broken files causing problems */
-	if (is->offset >= is->size)
+	const goffset size = input_stream_get_size(is);
+	const goffset offset = input_stream_get_offset(is);
+	if (offset >= size)
 		return;
 
-	count = is->size - is->offset;
+	count = size - offset;
 
 	/* Check and limit id3 tag size to prevent a stack overflow */
 	if (count == 0 || count > 4096)
diff --git a/src/decoder/dsf_decoder_plugin.c b/src/decoder/dsf_decoder_plugin.c
index 6700f739a..23576a629 100644
--- a/src/decoder/dsf_decoder_plugin.c
+++ b/src/decoder/dsf_decoder_plugin.c
@@ -165,14 +165,15 @@ dsf_read_metadata(struct decoder *decoder, struct input_stream *is,
 
 	metadata->chunk_size = data_size;
 	/* data_size cannot be bigger or equal to total file size */
-	if (data_size >= (unsigned) is->size)
+	const uint64_t size = (uint64_t)input_stream_get_size(is);
+	if (data_size >= size)
 		return false;
 
 	metadata->channels = (unsigned) dsf_fmt_chunk.channelnum;
 	metadata->sample_rate = samplefreq;
 #ifdef HAVE_ID3TAG
 	/* metada_offset cannot be bigger then or equal to total file size */
-	if (metadata_offset >= (unsigned) is->size)
+	if (metadata_offset >= size)
 		metadata->id3_offset = 0;
 	else
 		metadata->id3_offset = (goffset) metadata_offset;
diff --git a/src/decoder/faad_decoder_plugin.c b/src/decoder/faad_decoder_plugin.c
index 911f033b8..c8dbb966c 100644
--- a/src/decoder/faad_decoder_plugin.c
+++ b/src/decoder/faad_decoder_plugin.c
@@ -175,7 +175,8 @@ faad_song_duration(struct decoder_buffer *buffer, struct input_stream *is)
 	size_t length;
 	bool success;
 
-	fileread = is->size >= 0 ? is->size : 0;
+	const goffset size = input_stream_get_size(is);
+	fileread = size >= 0 ? size : 0;
 
 	decoder_buffer_fill(buffer);
 	data = decoder_buffer_read(buffer, &length);
@@ -201,7 +202,7 @@ faad_song_duration(struct decoder_buffer *buffer, struct input_stream *is)
 			return -1;
 	}
 
-	if (is->seekable && length >= 2 &&
+	if (input_stream_is_seekable(is) && length >= 2 &&
 	    data[0] == 0xFF && ((data[1] & 0xF6) == 0xF0)) {
 		/* obtain the duration from the ADTS header */
 		float song_length = adts_song_duration(buffer);
diff --git a/src/decoder/mad_decoder_plugin.c b/src/decoder/mad_decoder_plugin.c
index 0c27ac119..4e2e03311 100644
--- a/src/decoder/mad_decoder_plugin.c
+++ b/src/decoder/mad_decoder_plugin.c
@@ -755,7 +755,7 @@ mp3_frame_duration(const struct mad_frame *frame)
 static goffset
 mp3_this_frame_offset(const struct mp3_data *data)
 {
-	goffset offset = data->input_stream->offset;
+	goffset offset = input_stream_get_offset(data->input_stream);
 
 	if (data->stream.this_frame != NULL)
 		offset -= data->stream.bufend - data->stream.this_frame;
@@ -768,7 +768,8 @@ mp3_this_frame_offset(const struct mp3_data *data)
 static goffset
 mp3_rest_including_this_frame(const struct mp3_data *data)
 {
-	return data->input_stream->size - mp3_this_frame_offset(data);
+	return input_stream_get_size(data->input_stream)
+		- mp3_this_frame_offset(data);
 }
 
 /**
@@ -841,7 +842,7 @@ mp3_decode_first_frame(struct mp3_data *data, struct tag **tag)
 
 		if (parse_lame(&lame, &ptr, &bitlen)) {
 			if (gapless_playback &&
-			    data->input_stream->seekable) {
+			    input_stream_is_seekable(data->input_stream)) {
 				data->drop_start_samples = lame.encoder_delay +
 				                           DECODERDELAY;
 				data->drop_end_samples = lame.encoder_padding;
@@ -1081,7 +1082,7 @@ mp3_read(struct mp3_data *data)
 		if (cmd == DECODE_COMMAND_SEEK) {
 			unsigned long j;
 
-			assert(data->input_stream->seekable);
+			assert(input_stream_is_seekable(data->input_stream));
 
 			j = mp3_time_to_frame(data,
 					      decoder_seek_where(decoder));
@@ -1163,7 +1164,8 @@ mp3_decode(struct decoder *decoder, struct input_stream *input_stream)
 	}
 
 	decoder_initialized(decoder, &audio_format,
-			    data.input_stream->seekable, data.total_time);
+			    input_stream_is_seekable(input_stream),
+			    data.total_time);
 
 	if (tag != NULL) {
 		decoder_tag(decoder, input_stream, tag);
diff --git a/src/decoder/modplug_decoder_plugin.c b/src/decoder/modplug_decoder_plugin.c
index 21ee79e7e..bc3d81767 100644
--- a/src/decoder/modplug_decoder_plugin.c
+++ b/src/decoder/modplug_decoder_plugin.c
@@ -41,19 +41,21 @@ static GByteArray *mod_loadfile(struct decoder *decoder, struct input_stream *is
 	GByteArray *bdatas;
 	size_t ret;
 
-	if (is->size == 0) {
+	const goffset size = input_stream_get_size(is);
+
+	if (size == 0) {
 		g_warning("file is empty");
 		return NULL;
 	}
 
-	if (is->size > MODPLUG_FILE_LIMIT) {
+	if (size > MODPLUG_FILE_LIMIT) {
 		g_warning("file too large");
 		return NULL;
 	}
 
 	//known/unknown size, preallocate array, lets read in chunks
-	if (is->size > 0) {
-		bdatas = g_byte_array_sized_new(is->size);
+	if (size > 0) {
+		bdatas = g_byte_array_sized_new(size);
 	} else {
 		bdatas = g_byte_array_sized_new(MODPLUG_PREALLOC_BLOCK);
 	}
@@ -126,7 +128,8 @@ mod_decode(struct decoder *decoder, struct input_stream *is)
 	assert(audio_format_valid(&audio_format));
 
 	decoder_initialized(decoder, &audio_format,
-			    is->seekable, ModPlug_GetLength(f) / 1000.0);
+			    input_stream_is_seekable(is),
+			    ModPlug_GetLength(f) / 1000.0);
 
 	do {
 		ret = ModPlug_Read(f, audio_buffer, MODPLUG_FRAME_SIZE);
diff --git a/src/decoder/mpcdec_decoder_plugin.c b/src/decoder/mpcdec_decoder_plugin.c
index d4768b35b..77db2416b 100644
--- a/src/decoder/mpcdec_decoder_plugin.c
+++ b/src/decoder/mpcdec_decoder_plugin.c
@@ -70,7 +70,7 @@ mpc_tell_cb(cb_first_arg)
 {
 	struct mpc_decoder_data *data = (struct mpc_decoder_data *) cb_data;
 
-	return (long)(data->is->offset);
+	return (long)input_stream_get_offset(data->is);
 }
 
 static mpc_bool_t
@@ -78,7 +78,7 @@ mpc_canseek_cb(cb_first_arg)
 {
 	struct mpc_decoder_data *data = (struct mpc_decoder_data *) cb_data;
 
-	return data->is->seekable;
+	return input_stream_is_seekable(data->is);
 }
 
 static mpc_int32_t
@@ -86,7 +86,7 @@ mpc_getsize_cb(cb_first_arg)
 {
 	struct mpc_decoder_data *data = (struct mpc_decoder_data *) cb_data;
 
-	return data->is->size;
+	return input_stream_get_size(data->is);
 }
 
 /* this _looks_ performance-critical, don't de-inline -- eric */
@@ -222,7 +222,7 @@ mpcdec_decode(struct decoder *mpd_decoder, struct input_stream *is)
 	decoder_replay_gain(mpd_decoder, &replay_gain_info);
 
 	decoder_initialized(mpd_decoder, &audio_format,
-			    is->seekable,
+			    input_stream_is_seekable(is),
 			    mpc_streaminfo_get_length(&info));
 
 	do {
diff --git a/src/decoder/pcm_decoder_plugin.c b/src/decoder/pcm_decoder_plugin.c
index fc7dffc05..d529cef5c 100644
--- a/src/decoder/pcm_decoder_plugin.c
+++ b/src/decoder/pcm_decoder_plugin.c
@@ -38,8 +38,9 @@ pcm_stream_decode(struct decoder *decoder, struct input_stream *is)
 		.channels = 2,
 	};
 
-	const bool reverse_endian = is->mime != NULL &&
-		strcmp(is->mime, "audio/x-mpd-cdda-pcm-reverse") == 0;
+	const char *const mime = input_stream_get_mime_type(is);
+	const bool reverse_endian = mime != NULL &&
+		strcmp(mime, "audio/x-mpd-cdda-pcm-reverse") == 0;
 
 	GError *error = NULL;
 	enum decoder_command cmd;
@@ -47,10 +48,12 @@ pcm_stream_decode(struct decoder *decoder, struct input_stream *is)
 	double time_to_size = audio_format_time_to_size(&audio_format);
 
 	float total_time = -1;
-	if (is->size >= 0)
-		total_time = is->size / time_to_size;
+	const goffset size = input_stream_get_size(is);
+	if (size >= 0)
+		total_time = size / time_to_size;
 
-	decoder_initialized(decoder, &audio_format, is->seekable, total_time);
+	decoder_initialized(decoder, &audio_format,
+			    input_stream_is_seekable(is), total_time);
 
 	do {
 		char buffer[4096];
diff --git a/src/decoder/sndfile_decoder_plugin.c b/src/decoder/sndfile_decoder_plugin.c
index 8dd98236f..e70a2dc2e 100644
--- a/src/decoder/sndfile_decoder_plugin.c
+++ b/src/decoder/sndfile_decoder_plugin.c
@@ -32,7 +32,7 @@ sndfile_vio_get_filelen(void *user_data)
 {
 	const struct input_stream *is = user_data;
 
-	return is->size;
+	return input_stream_get_size(is);
 }
 
 static sf_count_t
@@ -45,7 +45,7 @@ sndfile_vio_seek(sf_count_t offset, int whence, void *user_data)
 	if (!success)
 		return -1;
 
-	return is->offset;
+	return input_stream_get_offset(is);
 }
 
 static sf_count_t
@@ -79,7 +79,7 @@ sndfile_vio_tell(void *user_data)
 {
 	const struct input_stream *is = user_data;
 
-	return is->offset;
+	return input_stream_get_offset(is);
 }
 
 /**
diff --git a/src/input/CdioParanoiaInputPlugin.cxx b/src/input/CdioParanoiaInputPlugin.cxx
index e8dabd88f..19001fbe9 100644
--- a/src/input/CdioParanoiaInputPlugin.cxx
+++ b/src/input/CdioParanoiaInputPlugin.cxx
@@ -24,6 +24,7 @@
 #include "config.h"
 #include "CdioParanoiaInputPlugin.hxx"
 #include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 #include "refcount.h"
 
diff --git a/src/input/CurlInputPlugin.cxx b/src/input/CurlInputPlugin.cxx
index ed70de072..a2ad20b15 100644
--- a/src/input/CurlInputPlugin.cxx
+++ b/src/input/CurlInputPlugin.cxx
@@ -19,12 +19,13 @@
 
 #include "config.h"
 #include "CurlInputPlugin.hxx"
+#include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 #include "conf.h"
 #include "tag.h"
 #include "IcyMetaDataParser.hxx"
 #include "event/MultiSocketMonitor.hxx"
-#include "InputInternal.hxx"
 #include "event/Loop.hxx"
 #include "IOThread.hxx"
 #include "glib_compat.h"
diff --git a/src/input/DespotifyInputPlugin.cxx b/src/input/DespotifyInputPlugin.cxx
index af550cab5..e17bbb663 100644
--- a/src/input/DespotifyInputPlugin.cxx
+++ b/src/input/DespotifyInputPlugin.cxx
@@ -21,6 +21,7 @@
 #include "DespotifyInputPlugin.hxx"
 #include "DespotifyUtils.hxx"
 #include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 #include "tag.h"
 
diff --git a/src/input/FfmpegInputPlugin.cxx b/src/input/FfmpegInputPlugin.cxx
index 3e59bca9c..1893a01e7 100644
--- a/src/input/FfmpegInputPlugin.cxx
+++ b/src/input/FfmpegInputPlugin.cxx
@@ -23,6 +23,7 @@
 #include "config.h"
 #include "FfmpegInputPlugin.hxx"
 #include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 
 extern "C" {
diff --git a/src/input/FileInputPlugin.cxx b/src/input/FileInputPlugin.cxx
index 8d3ef7510..2d0bfcbbb 100644
--- a/src/input/FileInputPlugin.cxx
+++ b/src/input/FileInputPlugin.cxx
@@ -20,6 +20,7 @@
 #include "config.h" /* must be first for large file support */
 #include "FileInputPlugin.hxx"
 #include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 #include "fd_util.h"
 #include "open.h"
diff --git a/src/input/MmsInputPlugin.cxx b/src/input/MmsInputPlugin.cxx
index 719aca29d..934521708 100644
--- a/src/input/MmsInputPlugin.cxx
+++ b/src/input/MmsInputPlugin.cxx
@@ -20,6 +20,7 @@
 #include "config.h"
 #include "MmsInputPlugin.hxx"
 #include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 
 #include <glib.h>
diff --git a/src/input/RewindInputPlugin.cxx b/src/input/RewindInputPlugin.cxx
index 241a5fb5a..d77bb1207 100644
--- a/src/input/RewindInputPlugin.cxx
+++ b/src/input/RewindInputPlugin.cxx
@@ -20,6 +20,7 @@
 #include "config.h"
 #include "RewindInputPlugin.hxx"
 #include "InputInternal.hxx"
+#include "InputStream.hxx"
 #include "InputPlugin.hxx"
 #include "tag.h"
 
diff --git a/src/input/SoupInputPlugin.cxx b/src/input/SoupInputPlugin.cxx
index 44c26be5a..be4892629 100644
--- a/src/input/SoupInputPlugin.cxx
+++ b/src/input/SoupInputPlugin.cxx
@@ -20,6 +20,7 @@
 #include "config.h"
 #include "SoupInputPlugin.hxx"
 #include "InputPlugin.hxx"
+#include "InputStream.hxx"
 #include "InputInternal.hxx"
 #include "IOThread.hxx"
 #include "event/Loop.hxx"
diff --git a/src/input_stream.h b/src/input_stream.h
index d5b1dae2e..0d32c0742 100644
--- a/src/input_stream.h
+++ b/src/input_stream.h
@@ -29,64 +29,7 @@
 #include <stdbool.h>
 #include <sys/types.h>
 
-struct input_stream {
-	/**
-	 * the plugin which implements this input stream
-	 */
-	const struct input_plugin *plugin;
-
-	/**
-	 * The absolute URI which was used to open this stream.  May
-	 * be NULL if this is unknown.
-	 */
-	char *uri;
-
-	/**
-	 * A mutex that protects the mutable attributes of this object
-	 * and its implementation.  It must be locked before calling
-	 * any of the public methods.
-	 *
-	 * This object is allocated by the client, and the client is
-	 * responsible for freeing it.
-	 */
-	GMutex *mutex;
-
-	/**
-	 * A cond that gets signalled when the state of this object
-	 * changes from the I/O thread.  The client of this object may
-	 * wait on it.  Optional, may be NULL.
-	 *
-	 * This object is allocated by the client, and the client is
-	 * responsible for freeing it.
-	 */
-	GCond *cond;
-
-	/**
-	 * indicates whether the stream is ready for reading and
-	 * whether the other attributes in this struct are valid
-	 */
-	bool ready;
-
-	/**
-	 * if true, then the stream is fully seekable
-	 */
-	bool seekable;
-
-	/**
-	 * the size of the resource, or -1 if unknown
-	 */
-	goffset size;
-
-	/**
-	 * the current offset within the stream
-	 */
-	goffset offset;
-
-	/**
-	 * the MIME content type of the resource, or NULL if unknown
-	 */
-	char *mime;
-};
+struct input_stream;
 
 #ifdef __cplusplus
 extern "C" {
@@ -119,20 +62,6 @@ gcc_nonnull(1)
 void
 input_stream_close(struct input_stream *is);
 
-gcc_nonnull(1)
-static inline void
-input_stream_lock(struct input_stream *is)
-{
-	g_mutex_lock(is->mutex);
-}
-
-gcc_nonnull(1)
-static inline void
-input_stream_unlock(struct input_stream *is)
-{
-	g_mutex_unlock(is->mutex);
-}
-
 /**
  * Check for errors that may have occurred in the I/O thread.
  *
@@ -167,6 +96,26 @@ gcc_nonnull(1)
 void
 input_stream_lock_wait_ready(struct input_stream *is);
 
+gcc_nonnull_all gcc_pure
+const char *
+input_stream_get_mime_type(const struct input_stream *is);
+
+gcc_nonnull_all
+void
+input_stream_override_mime_type(struct input_stream *is, const char *mime);
+
+gcc_nonnull_all gcc_pure
+goffset
+input_stream_get_size(const struct input_stream *is);
+
+gcc_nonnull_all gcc_pure
+goffset
+input_stream_get_offset(const struct input_stream *is);
+
+gcc_nonnull_all gcc_pure
+bool
+input_stream_is_seekable(const struct input_stream *is);
+
 /**
  * Determines whether seeking is cheap.  This is true for local files.
  */
diff --git a/src/playlist/LastFMPlaylistPlugin.cxx b/src/playlist/LastFMPlaylistPlugin.cxx
index 67192574d..36c89fea1 100644
--- a/src/playlist/LastFMPlaylistPlugin.cxx
+++ b/src/playlist/LastFMPlaylistPlugin.cxx
@@ -242,8 +242,7 @@ lastfm_open_uri(const char *uri, GMutex *mutex, GCond *cond)
 
 	/* last.fm does not send a MIME type, we have to fake it here
 	   :-( */
-	g_free(playlist->is->mime);
-	playlist->is->mime = g_strdup("application/xspf+xml");
+	input_stream_override_mime_type(playlist->is, "application/xspf+xml");
 
 	g_mutex_unlock(mutex);