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Subject[PATCH] Fix calculus of bitmap_scnprintf_len()
Date
The function bitmap_scnprintf_len() is currently not used, but the returned
value is 4 times larger than needed. This value is also only a good upper
bound. Which should be mentioned in the comment.

The correct number of chars needed for the buffer, exluding any new line and
terminating zero is:

int bitmap_scnprintf_len(int len)
{
return /* complete hunks with commas */
((len / CHUNKSZ) * 9)
/* partial hunk, 4 bits in one char */
+ (((len % CHUNKSZ) + 3) / 4)
/* one less comma, if no partial hunk */
- !(len % CHUNKSZ);
}
Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Cc: Mike Travis <travis@sgi.com>
Cc: Paul Jackson <pj@sgi.com>

---
lib/bitmap.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/lib/bitmap.c b/lib/bitmap.c
index a6939e1..47e6f0f 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -325,7 +325,7 @@ int bitmap_scnprintf_len(unsigned int len)
/* we need 9 chars per word for 32 bit words (8 hexdigits + sep/null) */
int bitslen = ALIGN(len, CHUNKSZ);
int wordlen = CHUNKSZ / 4;
- int buflen = (bitslen / wordlen) * (wordlen + 1) * sizeof(char);
+ int buflen = (bitslen / CHUNKSZ) * (wordlen + 1);

return buflen;
}
--
1.5.4


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