Bug 252614
| Summary: | /usr/bin/diff : BUG: Incorrectly displaying files as duplicates (includes fix) | ||||||
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| Product: | Base System | Reporter: | Jamie Landeg-Jones <jamie> | ||||
| Component: | bin | Assignee: | freebsd-bugs (Nobody) <bugs> | ||||
| Status: | Closed FIXED | ||||||
| Severity: | Affects Some People | CC: | bapt, jamie, kevans, lwhsu | ||||
| Priority: | --- | ||||||
| Version: | CURRENT | ||||||
| Hardware: | Any | ||||||
| OS: | Any | ||||||
| Attachments: |
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Adding bapt@ and kevans@ in case they want to look as they've hacked on diff(1) recently. A commit in branch main references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=fefb3c46a80fdde6f307e73a2b5b5aed806df1ce commit fefb3c46a80fdde6f307e73a2b5b5aed806df1ce Author: Jamie Landeg-Jones <jamie@catflap.org> AuthorDate: 2021-01-25 17:42:26 +0000 Commit: Baptiste Daroussin <bapt@FreeBSD.org> CommitDate: 2021-01-25 19:38:18 +0000 diff: fix incorrectly displaying files as duplicates When diff hits certain access errors, function diffreg() shows the error message, and then returns to the calling function, which calls print_status() with the return value. However, in these cases, the return value isn't changed from the initial default value of D_SAME. Normally, print_status() with a value of D_SAME does nothing, so this works out ok, however, if the "-s" flag is set, a message is displayed showing identicality: case D_SAME: if (sflag) printf("Files %s%s and %s%s are identical\n", path1, entry, path2, entry); break; This then produces such results as: % diff -s /COPYRIGHT /var/run/rpcbind.sock diff: /var/run/rpcbind.sock: Operation not supported Files /COPYRIGHT and /var/run/rpcbind.sock are identical % diff -s /COPYRIGHT /etc/master.passwd diff: /etc/master.passwd: Permission denied Files /COPYRIGHT and /etc/master.passwd are identical Create a D_ERROR status which is returned in such cases, and print_status() then deals with that status seperately from D_SAME PR: 252614 MFC after: 1 week usr.bin/diff/diff.c | 2 ++ usr.bin/diff/diff.h | 1 + usr.bin/diff/diffreg.c | 5 +++++ 3 files changed, 8 insertions(+) thank you, fixed, I will merge this next week to ensure we have it in freebsd 13.0 A commit in branch stable/13 references this bug: URL: https://cgit.FreeBSD.org/src/commit/?id=3728c4d3149553967532a97254737bdb2cd92417 commit 3728c4d3149553967532a97254737bdb2cd92417 Author: Jamie Landeg-Jones <jamie@catflap.org> AuthorDate: 2021-01-25 17:42:26 +0000 Commit: Baptiste Daroussin <bapt@FreeBSD.org> CommitDate: 2021-02-01 13:05:25 +0000 diff: fix incorrectly displaying files as duplicates When diff hits certain access errors, function diffreg() shows the error message, and then returns to the calling function, which calls print_status() with the return value. However, in these cases, the return value isn't changed from the initial default value of D_SAME. Normally, print_status() with a value of D_SAME does nothing, so this works out ok, however, if the "-s" flag is set, a message is displayed showing identicality: case D_SAME: if (sflag) printf("Files %s%s and %s%s are identical\n", path1, entry, path2, entry); break; This then produces such results as: % diff -s /COPYRIGHT /var/run/rpcbind.sock diff: /var/run/rpcbind.sock: Operation not supported Files /COPYRIGHT and /var/run/rpcbind.sock are identical % diff -s /COPYRIGHT /etc/master.passwd diff: /etc/master.passwd: Permission denied Files /COPYRIGHT and /etc/master.passwd are identical Create a D_ERROR status which is returned in such cases, and print_status() then deals with that status seperately from D_SAME PR: 252614 MFC after: 1 week (cherry picked from commit fefb3c46a80fdde6f307e73a2b5b5aed806df1ce) usr.bin/diff/diff.c | 2 ++ usr.bin/diff/diff.h | 1 + usr.bin/diff/diffreg.c | 5 +++++ 3 files changed, 8 insertions(+) (In reply to commit-hook from comment #4) Thanks Baptiste! |
Created attachment 221499 [details] patch to fix diff bug When diff hits certain access errors, function diffreg() shows the error message, and then returns to the calling function, which calls print_status() with the return value. However, in these cases, the return value isn't changed from the initial default value of D_SAME. Normally, print_status() with a value of D_SAME does nothing, so this works out ok, however, if the "-s" flag is set, a message is displayed showing identicality: case D_SAME: if (sflag) printf("Files %s%s and %s%s are identical\n", path1, entry, path2, entry); break; This then produces such results as: % diff -s /COPYRIGHT /var/run/rpcbind.sock diff: /var/run/rpcbind.sock: Operation not supported Files /COPYRIGHT and /var/run/rpcbind.sock are identical % diff -s /COPYRIGHT /etc/master.passwd diff: /etc/master.passwd: Permission denied Files /COPYRIGHT and /etc/master.passwd are identical A quick fix would be to alter the above line: if (sflag) to if (sflag && status & 2) A less hacky fix is attached as a patch. It creates a D_ERROR status which is returned in such cases, and print_status() then deals with that status seperately from D_SAME.