From: schwarze Date: Tue, 31 May 2022 20:21:40 +0000 (+0000) Subject: Rudimentary implementation of the \A escape sequence, following groff X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=75a6bad90285abd40458237c07b74234971ec412;p=openbsd Rudimentary implementation of the \A escape sequence, following groff semantics (test identifier for syntactical validity), not at all following the completely unrelated Heirloom semantics (define hyperlink target position). The main motivation for providing this implementation is to get \A into the parsing class ESCAPE_EXPAND that corresponds to groff parsing behaviour, which is quite similar to the \B escape sequence (test numerical expression for syntactical validity). This is likely to improve parsing of nested escape sequences in the future. Validation isn't perfect yet. In particular, this implementation rejects \A arguments containing some escape sequences that groff allows to slip through. But that is unlikely to cause trouble even in documents using \A for non-trivial purposes. Rejecting the nested escapes in question might even improve robustnest because the rejected names are unlikely to really be usable for practical purposes - no matter that groff dubiously considers them syntactically valid. --- diff --git a/share/man/man7/roff.7 b/share/man/man7/roff.7 index 191f35628c1..3e0dd7b1bed 100644 --- a/share/man/man7/roff.7 +++ b/share/man/man7/roff.7 @@ -1,4 +1,4 @@ -.\" $OpenBSD: roff.7,v 1.100 2022/05/31 18:08:02 schwarze Exp $ +.\" $OpenBSD: roff.7,v 1.101 2022/05/31 20:21:40 schwarze Exp $ .\" .\" Copyright (c) 2010-2019, 2022 Ingo Schwarze .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons @@ -2021,8 +2021,23 @@ End conditional input; see Paddable non-breaking space character. .It Ic \e0 Digit width space character. -.It Ic \eA\(aq Ns Ar string Ns Ic \(aq -Anchor definition; ignored by +.It Ic \eA\(aq Ns Ar name Ns Ic \(aq +Interpolate +.Sq 1 +if +.Ar name +is a syntactically valid identifier that can be used +as a name for a macro or user-defined string, or +.Sq 0 +otherwise. +This is a thoroughly non-portable groff extension. +Heirloom troff uses the same escape sequence with the same syntax +for a completely different purpose, +defining a hyperlink target position, also called an +.Dq anchor , +with the given +.Ar name . +The Heirloom semantics is not supported by .Xr mandoc 1 . .It Ic \ea Leader character; ignored by diff --git a/usr.bin/mandoc/roff.c b/usr.bin/mandoc/roff.c index 7158fa6e8cd..7c5a272824f 100644 --- a/usr.bin/mandoc/roff.c +++ b/usr.bin/mandoc/roff.c @@ -1,4 +1,4 @@ -/* $OpenBSD: roff.c,v 1.262 2022/05/31 18:08:02 schwarze Exp $ */ +/* $OpenBSD: roff.c,v 1.263 2022/05/31 20:21:40 schwarze Exp $ */ /* * Copyright (c) 2010-2015, 2017-2022 Ingo Schwarze * Copyright (c) 2008-2012, 2014 Kristaps Dzonsons @@ -1518,6 +1518,11 @@ roff_expand(struct roff *r, struct buf *buf, int ln, int pos, char ec) *dst++ = '"'; } continue; + case 'A': + ubuf[0] = iendarg > iarg ? '1' : '0'; + ubuf[1] = '\0'; + res = ubuf; + break; case 'B': npos = 0; ubuf[0] = iendarg > iarg && iend > iendarg && diff --git a/usr.bin/mandoc/roff_escape.c b/usr.bin/mandoc/roff_escape.c index f8f59bcab27..041a5357c0e 100644 --- a/usr.bin/mandoc/roff_escape.c +++ b/usr.bin/mandoc/roff_escape.c @@ -1,4 +1,4 @@ -/* $OpenBSD: roff_escape.c,v 1.4 2022/05/31 18:08:02 schwarze Exp $ */ +/* $OpenBSD: roff_escape.c,v 1.5 2022/05/31 20:21:40 schwarze Exp $ */ /* * Copyright (c) 2011, 2012, 2013, 2014, 2015, 2017, 2018, 2020, 2022 * Ingo Schwarze @@ -73,6 +73,7 @@ roff_escape(const char *buf, const int ln, const int aesc, int maxl; /* expected length of the argument */ int argl; /* actual length of the argument */ int c, i; /* for \[char...] parsing */ + int valid_A; /* for \A parsing */ enum mandoc_esc rval; /* return value */ enum mandocerr err; /* diagnostic code */ char esc_name; @@ -181,12 +182,12 @@ roff_escape(const char *buf, const int ln, const int aesc, /* Quoted arguments */ + case 'A': case 'B': case 'w': rval = ESCAPE_EXPAND; term = '\b'; break; - case 'A': case 'D': case 'H': case 'L': @@ -301,6 +302,7 @@ roff_escape(const char *buf, const int ln, const int aesc, /* Advance to the end of the argument. */ + valid_A = 1; iendarg = iarg; while (maxl > 0) { if (buf[iendarg] == '\0') { @@ -319,11 +321,20 @@ roff_escape(const char *buf, const int ln, const int aesc, break; } if (buf[iendarg] == buf[iesc]) { - if (roff_escape(buf, ln, iendarg, - &sesc, &sarg, &sendarg, &send) == ESCAPE_EXPAND) + switch (roff_escape(buf, ln, iendarg, + &sesc, &sarg, &sendarg, &send)) { + case ESCAPE_EXPAND: goto out_sub; + case ESCAPE_UNDEF: + break; + default: + valid_A = 0; + break; + } iendarg = iend = send; } else { + if (buf[iendarg] == ' ' || buf[iendarg] == '\t') + valid_A = 0; if (maxl != INT_MAX) maxl--; iend = ++iendarg; @@ -342,6 +353,10 @@ roff_escape(const char *buf, const int ln, const int aesc, buf[iarg] == '.' && buf[iarg + 1] == 'T') rval = ESCAPE_DEVICE; break; + case 'A': + if (valid_A == 0) + iendarg = iarg; + break; case 'O': switch (buf[iarg]) { case '0':