diff <(command1) <(command2) provides useful output, let's make it
possible for git to do the same.
Signed-off-by: Dennis Kaarsemaker <dennis@xxxxxxxxxxxxxxx>
---
diff-no-index.c | 9 +++++++++
diff.c | 18 ++++++++++++++++--
t/t4053-diff-no-index.sh | 10 ++++++++++
t/test-lib.sh | 4 ++++
4 files changed, 39 insertions(+), 2 deletions(-)
diff --git a/diff-no-index.c b/diff-no-index.c
index fe48f32ddd..1262a587e5 100644
--- a/diff-no-index.c
+++ b/diff-no-index.c
@@ -83,6 +83,15 @@ static struct diff_filespec *noindex_filespec(const char *name, int mode)
name = "/dev/null";
s = alloc_filespec(name);
fill_filespec(s, null_sha1, 0, mode);
+ /*
+ * In --no-index mode, we support reading from pipes. canon_mode, called by
+ * fill_filespec, gets confused by this and thinks we now have subprojects.
+ * To help the rest of the diff machinery along, we now override what
+ * canon_mode says. This is done here instead of in canon_mode, because the
+ * rest of git does not (and should not) support pipes.
+ */
+ if (S_ISFIFO(mode))
+ s->mode = S_IFREG | ce_permissions(mode);
if (name == file_from_standard_input)
populate_from_stdin(s);
return s;
diff --git a/diff.c b/diff.c
index 2afecfb939..4f74a54d74 100644
--- a/diff.c
+++ b/diff.c
@@ -2765,6 +2765,11 @@ static int diff_populate_gitlink(struct diff_filespec *s, int size_only)
return 0;
}
+static int should_mmap_file_contents(struct stat *st)
+{
+ return S_ISREG(st->st_mode);
+}
+
/*
* While doing rename detection and pickaxe operation, we may need to
* grab the data for the blob (or file) for our own in-core comparison.
@@ -2839,9 +2844,18 @@ int diff_populate_filespec(struct diff_filespec *s, unsigned int flags)
fd = open(s->path, O_RDONLY);
if (fd < 0)
goto err_empty;
- s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
+ if (!should_mmap_file_contents(&st)) {
+ struct strbuf sb = STRBUF_INIT;
+ strbuf_read(&sb, fd, 0);
+ s->size = sb.len;
+ s->data = strbuf_detach(&sb, NULL);
+ s->should_free = 1;
+ }
+ else {
+ s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
+ s->should_munmap = 1;
+ }
close(fd);
- s->should_munmap = 1;
/*
* Convert from working tree format to canonical git format
diff --git a/t/t4053-diff-no-index.sh b/t/t4053-diff-no-index.sh
index 8c87bffb34..2d9b322315 100755
--- a/t/t4053-diff-no-index.sh
+++ b/t/t4053-diff-no-index.sh
@@ -171,4 +171,14 @@ test_expect_success SYMLINKS 'diff --no-index --no-dereference does not follow s
test_cmp expect actual
'
+test_expect_success PROCESS_SUBSTITUTION 'diff --no-index works on fifos' '
+ cat >expect <<-EOF &&
+ @@ -1 +1 @@
+ -1
+ +2
+ EOF
+ test_expect_code 1 git diff --no-index --dereference <(echo 1) <(echo 2) | tail -n +5 > actual &&
+ test_cmp expect actual
+'
+
test_done
diff --git a/t/test-lib.sh b/t/test-lib.sh
index 11562bde10..78f3d24651 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -1128,3 +1128,7 @@ build_option () {
test_lazy_prereq LONG_IS_64BIT '
test 8 -le "$(build_option sizeof-long)"
'
+
+test_lazy_prereq PROCESS_SUBSTITUTION '
+ eval "foo=<(echo test)" 2>/dev/null
+'
--
2.12.0-437-g0cc2799