`git add` of an empty file with a filter pops complaints from
`copy_fd` about a bad file descriptor.
This traces back to these lines in sha1_file.c:index_core:
if (!size) {
ret = index_mem(sha1, NULL, size, type, path, flags);
The problem here is that content to be added to the index can be
supplied from an fd, or from a memory buffer, or from a pathname. This
call is supplying a NULL buffer pointer and a zero size.
Downstream logic takes the complete absence of a buffer to mean the
data is to be found elsewhere -- for instance, these, from convert.c:
if (params->src) {
write_err = (write_in_full(child_process.in, params->src,
params->size) < 0);
} else {
write_err = copy_fd(params->fd, child_process.in);
}
~If there's a buffer, write from that, otherwise the data must be coming
from an open fd.~
Perfectly reasonable logic in a routine that's going to write from
either a buffer or an fd.
So change `index_core` to supply an empty buffer when indexing an empty
file.
There's a patch out there that instead changes the logic quoted above to
take a `-1` fd to mean "use the buffer", but it seems to me that the
distinction between a missing buffer and an empty one carries intrinsic
semantics, where the logic change is adapting the code to handle
incorrect arguments.
Signed-off-by: Jim Hill <gjth...@gmail.com>
---
Okay, that's it: I'm officially laughably rusty, 'cause I'm laughing. This
applies your fix, _thank you_ for the caution. I get it: `true` can have
already exited by the time the write hits.
sha1_file.c | 2 +-
t/t0021-conversion.sh | 26 ++++++++++++++++++++++++++
2 files changed, 27 insertions(+), 1 deletion(-)
diff --git a/sha1_file.c b/sha1_file.c
index f860d67..61e2735 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -3186,7 +3186,7 @@ static int index_core(unsigned char *sha1, int fd, size_t
size,
int ret;
if (!size) {
- ret = index_mem(sha1, NULL, size, type, path, flags);
+ ret = index_mem(sha1, "", size, type, path, flags);
} else if (size <= SMALL_FILE_SIZE) {
char *buf = xmalloc(size);
if (size == read_in_full(fd, buf, size))
diff --git a/t/t0021-conversion.sh b/t/t0021-conversion.sh
index ca7d2a6..eee4761 100755
--- a/t/t0021-conversion.sh
+++ b/t/t0021-conversion.sh
@@ -216,4 +216,30 @@ test_expect_success EXPENSIVE 'filter large file' '
! test -s err
'
+test_expect_success "filter: clean empty file" '
+ git config filter.in-repo-header.clean "echo cleaned && cat" &&
+ git config filter.in-repo-header.smudge "sed 1d" &&
+
+ echo "empty-in-worktree filter=in-repo-header" >>.gitattributes &&
+ >empty-in-worktree &&
+
+ echo cleaned >expected &&
+ git add empty-in-worktree &&
+ git show :empty-in-worktree >actual &&
+ test_cmp expected actual
+'
+
+test_expect_success "filter: smudge empty file" '
+ git config filter.empty-in-repo.clean "cat >/dev/null" &&
+ git config filter.empty-in-repo.smudge "echo smudged && cat" &&
+
+ echo "empty-in-repo filter=empty-in-repo" >>.gitattributes &&
+ echo dead data walking >empty-in-repo &&
+ git add empty-in-repo &&
+
+ echo smudged >expected &&
+ git checkout-index --prefix=filtered- empty-in-repo &&
+ test_cmp expected filtered-empty-in-repo
+'
+
test_done
--
2.4.1.4.g08cda19
--
To unsubscribe from this list: send the line "unsubscribe git" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
