Windows builds alias snprintf to _snprintf, which leaves a truncated string unterminated - #1752
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htslib.h defined snprintf as _snprintf under _WIN32. Microsoft documents _snprintf as writing no terminating NUL when it truncates, so every raw snprintf in the engine produced an unterminated string on Windows, and only there. A user hit it through htsblk.msg[80]: the crawler aborted in htsparse.c reading a failure message that had filled the field. Drop the alias, route the writers of r.msg through htsblk_failf(), and add a test that fails on any macro renaming a C99 printf call, since a Linux build cannot see one. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
Review findings on this branch. Test 490 collided with the number PR #1743 claims, so the file moves to 491. Its scan reported a clean tree whatever the file list held, so it now floors the count. It also missed the alias handed to the compiler rather than written in a header, which is how a Visual Studio build would carry one, so it reads the project files too. The no-argument message in htsback.c goes back to snprintf: its text is 65 bytes, so it cannot fill the field and the conversion bought nothing. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
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A user reported WinHTTrack 3.50-2 aborting with
size < sizeof_sourceathtsparse.c:4976. That line copiesback[b].r.msg, and the abort says those 80 bytes held no terminating NUL.htslib.haliasedsnprintfto_snprintfunder_WIN32. Microsoft documents_snprintfas writing no terminator when it truncates, while the UCRTsnprintfthe alias hid is C99-conformant. So the engine's 89 rawsnprintfcalls left their destination unterminated on Windows and nowhere else. Dropping the alias is the fix.The six failure messages that land in
r.msgnow go throughhtsblk_failf(), which clips. Three carry text the crawl does not control, and do overflow 80 bytes: a link's port, a server'sContent-Encoding, and the resolver's message.Test 491 fails on any macro renaming a C99 printf call, and on the same alias handed to the compiler as a define. A Linux build sees neither.
Closes #1753