From d019f1f6d4b986db56f6fa599968bc395d7ce072 Mon Sep 17 00:00:00 2001 From: Ingo Schwarze Date: Sun, 4 Jun 2017 00:13:15 +0000 Subject: Pure preprocessor implementation of the roff(7) .ec and .eo requests (escape character control), touching nothing after the preprocessing stage and keeping even the state variable local to the preprocessor. Since the escape character is also used for line continuation, this requires pulling the implementation of line continuation from the input reader to the preprocessor, which also considerably shortens the code required for that. When the escape character is changed, simply let the preprocessor replace bare by escaped backslashes and instances of the non-standard escape character with bare backslashes - that's all we need. Oh, and if anybody dares to use these requests in OpenBSD manuals, sending a medium-sized pack of axe-murderers after them might be a worthwhile part of the punishment, but probably insuffient on its own. --- roff.c | 114 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 100 insertions(+), 14 deletions(-) (limited to 'roff.c') diff --git a/roff.c b/roff.c index 082eb556..9874edcb 100644 --- a/roff.c +++ b/roff.c @@ -1,4 +1,4 @@ -/* $Id: roff.c,v 1.302 2017/05/08 20:33:53 schwarze Exp $ */ +/* $Id: roff.c,v 1.303 2017/06/04 00:13:15 schwarze Exp $ */ /* * Copyright (c) 2008-2012, 2014 Kristaps Dzonsons * Copyright (c) 2010-2015, 2017 Ingo Schwarze @@ -99,6 +99,7 @@ struct roff { int format; /* current file in mdoc or man format */ int argc; /* number of args of the last macro */ char control; /* control character */ + char escape; /* escape character */ }; struct roffnode { @@ -155,6 +156,8 @@ static enum rofferr roff_cond(ROFF_ARGS); static enum rofferr roff_cond_text(ROFF_ARGS); static enum rofferr roff_cond_sub(ROFF_ARGS); static enum rofferr roff_ds(ROFF_ARGS); +static enum rofferr roff_ec(ROFF_ARGS); +static enum rofferr roff_eo(ROFF_ARGS); static enum rofferr roff_eqndelim(struct roff *, struct buf *, int); static int roff_evalcond(struct roff *r, int, char *, int *); static int roff_evalnum(struct roff *, int, @@ -385,13 +388,13 @@ static struct roffmac roffs[TOKEN_NONE] = { { roff_ds, NULL, NULL, 0 }, /* ds1 */ { roff_unsupp, NULL, NULL, 0 }, /* dwh */ { roff_unsupp, NULL, NULL, 0 }, /* dt */ - { roff_unsupp, NULL, NULL, 0 }, /* ec */ + { roff_ec, NULL, NULL, 0 }, /* ec */ { roff_unsupp, NULL, NULL, 0 }, /* ecr */ { roff_unsupp, NULL, NULL, 0 }, /* ecs */ { roff_cond, roff_cond_text, roff_cond_sub, ROFFMAC_STRUCT }, /* el */ { roff_unsupp, NULL, NULL, 0 }, /* em */ { roff_EN, NULL, NULL, 0 }, /* EN */ - { roff_unsupp, NULL, NULL, 0 }, /* eo */ + { roff_eo, NULL, NULL, 0 }, /* eo */ { roff_unsupp, NULL, NULL, 0 }, /* EP */ { roff_EQ, NULL, NULL, 0 }, /* EQ */ { roff_line_ignore, NULL, NULL, 0 }, /* errprint */ @@ -751,7 +754,8 @@ roff_reset(struct roff *r) { roff_free1(r); r->format = r->options & (MPARSE_MDOC | MPARSE_MAN); - r->control = 0; + r->control = '\0'; + r->escape = '\\'; } void @@ -773,6 +777,7 @@ roff_alloc(struct mparse *parse, int options) r->options = options; r->format = options & (MPARSE_MDOC | MPARSE_MAN); r->rstackpos = -1; + r->escape = '\\'; return r; } @@ -1149,27 +1154,80 @@ roff_res(struct roff *r, struct buf *buf, int ln, int pos) int expand_count; /* to avoid infinite loops */ int npos; /* position in numeric expression */ int arg_complete; /* argument not interrupted by eol */ + int done; /* no more input available */ char term; /* character terminating the escape */ - expand_count = 0; + /* Search forward for comments. */ + + done = 0; start = buf->buf + pos; - stesc = strchr(start, '\0') - 1; - while (stesc-- > start) { + for (stesc = buf->buf + pos; *stesc != '\0'; stesc++) { + if (stesc[0] != r->escape || stesc[1] == '\0') + continue; + stesc++; + if (*stesc != '"' && *stesc != '#') + continue; + cp = strchr(stesc--, '\0') - 1; + if (*cp == '\n') { + done = 1; + cp--; + } + if (*cp == ' ' || *cp == '\t') + mandoc_msg(MANDOCERR_SPACE_EOL, r->parse, + ln, cp - buf->buf, NULL); + while (stesc > start && stesc[-1] == ' ') + stesc--; + *stesc = '\0'; + break; + } + if (stesc == start) + return ROFF_CONT; + stesc--; + + /* Notice the end of the input. */ + + if (*stesc == '\n') { + *stesc-- = '\0'; + done = 1; + } + + expand_count = 0; + while (stesc >= start) { /* Search backwards for the next backslash. */ - if (*stesc != '\\') + if (*stesc != r->escape) { + if (*stesc == '\\') { + *stesc = '\0'; + buf->sz = mandoc_asprintf(&nbuf, "%s\\e%s", + buf->buf, stesc + 1) + 1; + start = nbuf + pos; + stesc = nbuf + (stesc - buf->buf); + free(buf->buf); + buf->buf = nbuf; + } + stesc--; continue; + } /* If it is escaped, skip it. */ for (cp = stesc - 1; cp >= start; cp--) - if (*cp != '\\') + if (*cp != r->escape) break; if ((stesc - cp) % 2 == 0) { - stesc = (char *)cp; + while (stesc > cp) + *stesc-- = '\\'; continue; + } else if (stesc[1] != '\0') { + *stesc = '\\'; + } else { + *stesc-- = '\0'; + if (done) + continue; + else + return ROFF_APPEND; } /* Decide whether to expand or to check only. */ @@ -1195,6 +1253,7 @@ roff_res(struct roff *r, struct buf *buf, int ln, int pos) mandoc_vmsg(MANDOCERR_ESC_BAD, r->parse, ln, (int)(stesc - buf->buf), "%.*s", (int)(cp - stesc), stesc); + stesc--; continue; } @@ -1409,7 +1468,7 @@ roff_parseln(struct roff *r, int ln, struct buf *buf, int *offs) /* Expand some escape sequences. */ e = roff_res(r, buf, ln, pos); - if (e == ROFF_IGN) + if (e == ROFF_IGN || e == ROFF_APPEND) return e; assert(e == ROFF_CONT); @@ -2849,7 +2908,7 @@ roff_cc(ROFF_ARGS) p = buf->buf + pos; if (*p == '\0' || (r->control = *p++) == '.') - r->control = 0; + r->control = '\0'; if (*p != '\0') mandoc_vmsg(MANDOCERR_ARG_EXCESS, r->parse, @@ -2858,6 +2917,33 @@ roff_cc(ROFF_ARGS) return ROFF_IGN; } +static enum rofferr +roff_ec(ROFF_ARGS) +{ + const char *p; + + p = buf->buf + pos; + if (*p == '\0') + r->escape = '\\'; + else { + r->escape = *p; + if (*++p != '\0') + mandoc_vmsg(MANDOCERR_ARG_EXCESS, r->parse, + ln, p - buf->buf, "ec ... %s", p); + } + return ROFF_IGN; +} + +static enum rofferr +roff_eo(ROFF_ARGS) +{ + r->escape = '\0'; + if (buf->buf[pos] != '\0') + mandoc_vmsg(MANDOCERR_ARG_SKIP, r->parse, + ln, pos, "eo %s", buf->buf + pos); + return ROFF_IGN; +} + static enum rofferr roff_tr(ROFF_ARGS) { @@ -3385,9 +3471,9 @@ roff_getcontrol(const struct roff *r, const char *cp, int *ppos) pos = *ppos; - if (0 != r->control && cp[pos] == r->control) + if (r->control != '\0' && cp[pos] == r->control) pos++; - else if (0 != r->control) + else if (r->control != '\0') return 0; else if ('\\' == cp[pos] && '.' == cp[pos + 1]) pos += 2; -- cgit v1.2.3-56-ge451