path: root/include/linux/decompress/generic.h
diff options
authorPhillip Lougher <>2009-08-06 15:09:30 -0700
committerLinus Torvalds <>2009-08-07 10:39:56 -0700
commitdaeb6b6fbe27049f465c48a7d0ee5555c3b84064 (patch)
tree3a53744300e0083f3cbf8f769780d971234e3f8a /include/linux/decompress/generic.h
parent9c8a8228d0827e0d91d28527209988f672f97d28 (diff)
bzip2/lzma/gzip: fix comments describing decompressor API
Fix and improve comments in decompress/generic.h that describe the decompressor API. Also remove an unused definition, and rename INBUF_LEN in lib/decompress_inflate.c to conform to bzip2/lzma naming. Signed-off-by: Phillip Lougher <> Cc: "H. Peter Anvin" <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'include/linux/decompress/generic.h')
1 files changed, 19 insertions, 13 deletions
diff --git a/include/linux/decompress/generic.h b/include/linux/decompress/generic.h
index 6dfb856327bb..0c7111a55a1a 100644
--- a/include/linux/decompress/generic.h
+++ b/include/linux/decompress/generic.h
@@ -1,31 +1,37 @@
-/* Minimal chunksize to be read.
- *Bzip2 prefers at least 4096
- *Lzma prefers 0x10000 */
-#define COMPR_IOBUF_SIZE 4096
typedef int (*decompress_fn) (unsigned char *inbuf, int len,
int(*fill)(void*, unsigned int),
- int(*writebb)(void*, unsigned int),
- unsigned char *output,
+ int(*flush)(void*, unsigned int),
+ unsigned char *outbuf,
int *posp,
void(*error)(char *x));
/* inbuf - input buffer
*len - len of pre-read data in inbuf
- *fill - function to fill inbuf if empty
- *writebb - function to write out outbug
+ *fill - function to fill inbuf when empty
+ *flush - function to write out outbuf
+ *outbuf - output buffer
*posp - if non-null, input position (number of bytes read) will be
* returned here
- *If len != 0, the inbuf is initialized (with as much data), and fill
- *should not be called
- *If len = 0, the inbuf is allocated, but empty. Its size is IOBUF_SIZE
- *fill should be called (repeatedly...) to read data, at most IOBUF_SIZE
+ *If len != 0, inbuf should contain all the necessary input data, and fill
+ *should be NULL
+ *If len = 0, inbuf can be NULL, in which case the decompressor will allocate
+ *the input buffer. If inbuf != NULL it must be at least XXX_IOBUF_SIZE bytes.
+ *fill will be called (repeatedly...) to read data, at most XXX_IOBUF_SIZE
+ *bytes should be read per call. Replace XXX with the appropriate decompressor
+ *name, i.e. LZMA_IOBUF_SIZE.
+ *
+ *If flush = NULL, outbuf must be large enough to buffer all the expected
+ *output. If flush != NULL, the output buffer will be allocated by the
+ *decompressor (outbuf = NULL), and the flush function will be called to
+ *flush the output buffer at the appropriate time (decompressor and stream
+ *dependent).
/* Utility routine to detect the decompression method */
decompress_fn decompress_method(const unsigned char *inbuf, int len,
const char **name);