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| author | Ed Maste <emaste@FreeBSD.org> | 2021-01-11 00:02:56 +0000 |
|---|---|---|
| committer | Ed Maste <emaste@FreeBSD.org> | 2021-01-11 00:02:56 +0000 |
| commit | 80445b7a3f738e0b0a33ee7a11905a275346a6de (patch) | |
| tree | e5a80f94177d3b234b1cadf3260f04b7cdaa17b9 /usr.bin | |
| parent | 1f7661742de650bcb6b9124ee3da7e94c8650c4b (diff) | |
| download | src-80445b7a3f738e0b0a33ee7a11905a275346a6de.tar.gz src-80445b7a3f738e0b0a33ee7a11905a275346a6de.zip | |
cmp: fix -s (silent) when used with skip offsets
-s causes cmp to print nothing for differing files, for use when only
the exit status is of interest.
-z compares the file size first, for regular files, and fails the
comparison early if they do not match.
Prior to this change -s implied -z as an optimization, but this is not
valid when file offsets are specified. Now, enable the -z optimization
for -s only if both skip arguments are not provided / 0.
Note that using -z with differing skip values will currently always
fail. We may want to compare size1 - skip1 with size2 - skip2 instaead,
and in any case the man page should be clarified.
PR: 252542
Fixes: 3e6902efc802ab57fc4e9bf798f2d271b152e7f9
Reported by: William Ahern
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D28071
Diffstat (limited to 'usr.bin')
| -rw-r--r-- | usr.bin/cmp/cmp.c | 4 | ||||
| -rwxr-xr-x | usr.bin/cmp/tests/cmp_test2.sh | 14 |
2 files changed, 17 insertions, 1 deletions
diff --git a/usr.bin/cmp/cmp.c b/usr.bin/cmp/cmp.c index c762f1346abf..47f9b671985c 100644 --- a/usr.bin/cmp/cmp.c +++ b/usr.bin/cmp/cmp.c @@ -92,7 +92,6 @@ main(int argc, char *argv[]) break; case 's': /* silent run */ sflag = true; - zflag = true; break; case 'x': /* hex output */ lflag = true; @@ -149,6 +148,9 @@ main(int argc, char *argv[]) skip1 = argc > 2 ? strtol(argv[2], NULL, 0) : 0; skip2 = argc == 4 ? strtol(argv[3], NULL, 0) : 0; + if (sflag && skip1 == 0 && skip2 == 0) + zflag = true; + if (fd1 == -1) { if (fd2 == -1) { c_link(file1, skip1, file2, skip2); diff --git a/usr.bin/cmp/tests/cmp_test2.sh b/usr.bin/cmp/tests/cmp_test2.sh index 2b0d66382d36..7f9801fc92bd 100755 --- a/usr.bin/cmp/tests/cmp_test2.sh +++ b/usr.bin/cmp/tests/cmp_test2.sh @@ -62,8 +62,22 @@ symlink_body() { atf_check -s not-exit:0 -o ignore -e ignore cmp -h a.lnk adup.lnk } +atf_test_case pr252542 +pr252542_head() +{ + atf_set "descr" "Test cmp(1) -s with file offset skips" +} +pr252542_body() +{ + echo -n '1234567890' > a + echo -n 'abc567890' > b + atf_check -s exit:0 cmp -s a b 4 3 + atf_check -s exit:1 -o ignore cmp -z a b 4 3 +} + atf_init_test_cases() { atf_add_test_case special atf_add_test_case symlink + atf_add_test_case pr252542 } |