* maint-1.6.2:
base85: Make the code more obvious instead of explaining the non-obvious
base85: encode_85() does not use the decode table
base85 debug code: Fix length byte calculation
checkout -m: do not try to fall back to --merge from an unborn branch
Conflicts:
diff.c
Shifting 'unsigned char' or 'unsigned short' left can result in sign
extension errors, since the C integer promotion rules means that the
unsigned char/short will get implicitly promoted to a signed 'int' due to
the shift (or due to other operations).
This normally doesn't matter, but if you shift things up sufficiently, it
will now set the sign bit in 'int', and a subsequent cast to a bigger type
(eg 'long' or 'unsigned long') will now sign-extend the value despite the
original expression being unsigned.
One example of this would be something like
unsigned long size;
unsigned char c;
size += c << 24;
where despite all the variables being unsigned, 'c << 24' ends up being a
signed entity, and will get sign-extended when then doing the addition in
an 'unsigned long' type.
Since git uses 'unsigned char' pointers extensively, we actually have this
bug in a couple of places.
I may have missed some, but this is the result of looking at
git grep '[^0-9 ][ ]*<<[ ][a-z]' -- '*.c' '*.h'
git grep '<<[ ]*24'
which catches at least the common byte cases (shifting variables by a
variable amount, and shifting by 24 bits).
I also grepped for just 'unsigned char' variables in general, and
converted the ones that most obviously ended up getting implicitly cast
immediately anyway (eg hash_name(), encode_85()).
In addition to just avoiding 'unsigned char', this patch also tries to use
a common idiom for the delta header size thing. We had three different
variations on it: "& 0x7fUL" in one place (getting the sign extension
right), and "& ~0x80" and "& 0x7f" in two other places (not getting it
right). Apart from making them all just avoid using "unsigned char" at
all, I also unified them to then use a simple "& 0x7f".
I considered making a sparse extension which warns about doing implicit
casts from unsigned types to signed types, but it gets rather complex very
quickly, so this is just a hack.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the function detected an invalid base85 sequence, it issued
an error message but forgot to return error status at that point
and kept going.
Signed-off-by: Jerald Fitzjerald <jfj@freemail.gr>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This code is arguably pretty hot, if you use binary patches of course.
This patch helps gcc generate both smaller and faster code especially in
the error free path.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
This updates the user interface and generated diff data format.
* "diff --binary" is used to signal that we want an e-mailable
binary patch. It implies --full-index and -p.
* "apply --allow-binary-replacement" acquired a short synonym
"apply --binary".
* After the "GIT binary patch\n" header line there is a token
to record which binary patch mechanism was used, so that we
can extend it later. Currently there are two mechanisms
defined: "literal" and "delta". The former records the
deflated postimage and the latter records the deflated delta
from the preimage to postimage.
For purely implementation convenience, I added the deflated
length after these "literal/delta" tokens (otherwise the
decoding side needs to guess and reallocate the buffer while
inflating). Improvement patches are very welcomed.
Signed-off-by: Junio C Hamano <junkio@cox.net>
