diff options
Diffstat (limited to 'src/InputStream.hxx')
-rw-r--r-- | src/InputStream.hxx | 199 |
1 files changed, 184 insertions, 15 deletions
diff --git a/src/InputStream.hxx b/src/InputStream.hxx index 039f59076..eac7b0806 100644 --- a/src/InputStream.hxx +++ b/src/InputStream.hxx @@ -20,7 +20,6 @@ #ifndef MPD_INPUT_STREAM_HXX #define MPD_INPUT_STREAM_HXX -#include "InputLegacy.hxx" #include "check.h" #include "thread/Mutex.hxx" #include "thread/Cond.hxx" @@ -28,8 +27,13 @@ #include <string> +#include <glib.h> + #include <assert.h> +class Error; +struct Tag; + struct input_stream { /** * the plugin which implements this input stream @@ -95,20 +99,185 @@ struct input_stream { size(-1), offset(0) { assert(_uri != NULL); } -}; -gcc_nonnull(1) -static inline void -input_stream_lock(struct input_stream *is) -{ - is->mutex.lock(); -} - -gcc_nonnull(1) -static inline void -input_stream_unlock(struct input_stream *is) -{ - is->mutex.unlock(); -} + /** + * Opens a new input stream. You may not access it until the "ready" + * flag is set. + * + * @param mutex a mutex that is used to protect this object; must be + * locked before calling any of the public methods + * @param cond a cond that gets signalled when the state of + * this object changes; may be NULL if the caller doesn't want to get + * notifications + * @return an #input_stream object on success, NULL on error + */ + gcc_nonnull_all + gcc_malloc + static input_stream *Open(const char *uri, Mutex &mutex, Cond &cond, + Error &error); + + /** + * Close the input stream and free resources. + * + * The caller must not lock the mutex. + */ + void Close(); + + void Lock() { + mutex.lock(); + } + + void Unlock() { + mutex.unlock(); + } + + /** + * Check for errors that may have occurred in the I/O thread. + * + * @return false on error + */ + bool Check(Error &error); + + /** + * Update the public attributes. Call before accessing attributes + * such as "ready" or "offset". + */ + void Update(); + + /** + * Wait until the stream becomes ready. + * + * The caller must lock the mutex. + */ + void WaitReady(); + + /** + * Wrapper for WaitReady() which locks and unlocks the mutex; + * the caller must not be holding it already. + */ + void LockWaitReady(); + + gcc_pure + const char *GetMimeType() const { + assert(ready); + + return mime.empty() ? nullptr : mime.c_str(); + } + + gcc_nonnull_all + void OverrideMimeType(const char *_mime) { + assert(ready); + + mime = _mime; + } + + gcc_pure + goffset GetSize() const { + assert(ready); + + return size; + } + + gcc_pure + goffset GetOffset() const { + assert(ready); + + return offset; + } + + gcc_pure + bool IsSeekable() const { + assert(ready); + + return seekable; + } + + /** + * Determines whether seeking is cheap. This is true for local files. + */ + gcc_pure + bool CheapSeeking() const; + + /** + * Seeks to the specified position in the stream. This will most + * likely fail if the "seekable" flag is false. + * + * The caller must lock the mutex. + * + * @param offset the relative offset + * @param whence the base of the seek, one of SEEK_SET, SEEK_CUR, SEEK_END + */ + bool Seek(goffset offset, int whence, Error &error); + + /** + * Wrapper for Seek() which locks and unlocks the mutex; the + * caller must not be holding it already. + */ + bool LockSeek(goffset offset, int whence, Error &error); + + /** + * Returns true if the stream has reached end-of-file. + * + * The caller must lock the mutex. + */ + gcc_pure + bool IsEOF(); + + /** + * Wrapper for IsEOF() which locks and unlocks the mutex; the + * caller must not be holding it already. + */ + gcc_pure + bool LockIsEOF(); + + /** + * Reads the tag from the stream. + * + * The caller must lock the mutex. + * + * @return a tag object which must be freed by the caller, or + * nullptr if the tag has not changed since the last call + */ + gcc_malloc + Tag *ReadTag(); + + /** + * Wrapper for ReadTag() which locks and unlocks the mutex; + * the caller must not be holding it already. + */ + gcc_malloc + Tag *LockReadTag(); + + /** + * Returns true if the next read operation will not block: either data + * is available, or end-of-stream has been reached, or an error has + * occurred. + * + * The caller must lock the mutex. + */ + gcc_pure + bool IsAvailable(); + + /** + * Reads data from the stream into the caller-supplied buffer. + * Returns 0 on error or eof (check with IsEOF()). + * + * The caller must lock the mutex. + * + * @param is the input_stream object + * @param ptr the buffer to read into + * @param size the maximum number of bytes to read + * @return the number of bytes read + */ + gcc_nonnull_all + size_t Read(void *ptr, size_t size, Error &error); + + /** + * Wrapper for Read() which locks and unlocks the mutex; + * the caller must not be holding it already. + */ + gcc_nonnull_all + size_t LockRead(void *ptr, size_t size, Error &error); +}; #endif |