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| author |   Ingo Schwarze <schwarze@openbsd.org> | 2020-09-03 20:43:15 +0000 |
|---|---|---|
| committer | Ingo Schwarze <schwarze@openbsd.org> | 2020-09-03 20:43:15 +0000 |
| commit | 30fa4bfa1d93f60689c0c47c0e532f2fc5cae39b (patch) | |
| tree | e62635ab2894ae0057f41ed472a2402872371802 /roff_term.c | |
| parent | b71589000b1859d45cf1f2c247dc91fabf4f6753 (diff) | |
| download | mandoc-30fa4bfa1d93f60689c0c47c0e532f2fc5cae39b.tar.gz mandoc-30fa4bfa1d93f60689c0c47c0e532f2fc5cae39b.tar.zst mandoc-30fa4bfa1d93f60689c0c47c0e532f2fc5cae39b.zip | |
Fix two issues with .po (page offset) formatting:
1. Truncate excessive offsets to a width reasonable in the context
of manual pages instead of printing excessively long lines
and sometimes causing assertion failures;
found in an afl run performed by Jan Schreiber <jes at posteo dot de>.
2. Remember both the requested and the applied page offset; otherwise,
subtracting an excessive width, then adding it again, would end up
with an incorrectly large offset.
While here, simplify the code by reverting the previous offset up front,
and also add some comments to make the general ideas easier to understand.
Diffstat (limited to 'roff_term.c')
| -rw-r--r-- | roff_term.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/roff_term.c b/roff_term.c index ebfb75ef..7f5058a4 100644 --- a/roff_term.c +++ b/roff_term.c @@ -1,6 +1,6 @@ -/* $Id: roff_term.c,v 1.21 2020/09/03 17:42:15 schwarze Exp $ */ +/* $OpenBSD: roff_term.c,v 1.20 2020/09/03 17:37:06 schwarze Exp $ */ /* - * Copyright (c) 2010,2014,2015,2017-2019 Ingo Schwarze <schwarze@openbsd.org> + * Copyright (c) 2010,2014,2015,2017-2020 Ingo Schwarze <schwarze@openbsd.org> * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above @@ -157,9 +157,13 @@ static void roff_term_pre_po(ROFF_TERM_ARGS) { struct roffsu su; - static int po, polast; + static int po, pouse, polast; int ponew; + /* Revert the currently active page offset. */ + p->tcol->offset -= pouse; + + /* Determine the requested page offset. */ if (n->child != NULL && a2roffsu(n->child->string, &su, SCALE_EM) != NULL) { ponew = term_hen(p, &su); @@ -168,11 +172,15 @@ roff_term_pre_po(ROFF_TERM_ARGS) ponew += po; } else ponew = polast; + + /* Remeber both the previous and the newly requested offset. */ polast = po; po = ponew; - ponew = po - polast + (int)p->tcol->offset; - p->tcol->offset = ponew > 0 ? ponew : 0; + /* Truncate to the range [-offset, 60], remember, and apply it. */ + pouse = po >= 60 ? 60 : + po < -(int)p->tcol->offset ? -p->tcol->offset : po; + p->tcol->offset += pouse; } static void |