1 files changed, 34 insertions, 7 deletions
diff --git a/third_party/ffmpeg/include/libavutil/lzo.h b/third_party/ffmpeg/include/libavutil/lzo.h
index 2f09f9f..6788054 100644
--- a/third_party/ffmpeg/include/libavutil/lzo.h
+++ b/third_party/ffmpeg/include/libavutil/lzo.h
@@ -24,16 +24,43 @@
 
 #include <stdint.h>
 
-#define LZO_INPUT_DEPLETED 1
-#define LZO_OUTPUT_FULL 2
-#define LZO_INVALID_BACKPTR 4
-#define LZO_ERROR 8
+/** \defgroup errflags Error flags returned by av_lzo1x_decode
+  * \{ */
+//! end of the input buffer reached before decoding finished
+#define AV_LZO_INPUT_DEPLETED 1
+//! decoded data did not fit into output buffer
+#define AV_LZO_OUTPUT_FULL 2
+//! a reference to previously decoded data was wrong
+#define AV_LZO_INVALID_BACKPTR 4
+//! a non-specific error in the compressed bitstream
+#define AV_LZO_ERROR 8
+/** \} */
 
-#define LZO_INPUT_PADDING 8
-#define LZO_OUTPUT_PADDING 12
+#define AV_LZO_INPUT_PADDING 8
+#define AV_LZO_OUTPUT_PADDING 12
 
-int lzo1x_decode(void *out, int *outlen, const void *in, int *inlen);
+/**
+ * \brief Decodes LZO 1x compressed data.
+ * \param out output buffer
+ * \param outlen size of output buffer, number of bytes left are returned here
+ * \param in input buffer
+ * \param inlen size of input buffer, number of bytes left are returned here
+ * \return 0 on success, otherwise a combination of the error flags above
+ *
+ * Make sure all buffers are appropriately padded, in must provide
+ * AV_LZO_INPUT_PADDING, out must provide AV_LZO_OUTPUT_PADDING additional bytes.
+ */
+int av_lzo1x_decode(void *out, int *outlen, const void *in, int *inlen);
 
+/**
+ * \brief deliberately overlapping memcpy implementation
+ * \param dst destination buffer; must be padded with 12 additional bytes
+ * \param back how many bytes back we start (the initial size of the overlapping window)
+ * \param cnt number of bytes to copy, must be >= 0
+ *
+ * cnt > back is valid, this will copy the bytes we just copied,
+ * thus creating a repeating pattern with a period length of back.
+ */
 void av_memcpy_backptr(uint8_t *dst, int back, int cnt);
 
 #endif /* AVUTIL_LZO_H */