Add `cc' support.

This was reported by espie@ and in the TODO.
Caveat: `cc' has buggy behaviour when invoked in groff(1) and followed
by a line-breaking control character macro, e.g., in a -man doc,

  .cc |
  .B foo
  'B foo
  |cc
  'B foo

will cause groff(1) to behave properly for `.B' but inline the macro
definition for `B' when invoked with the line-breaking macro.

7 files changed, 74 insertions, 33 deletions

diff --git a/TODO b/TODO
index d2619a25..3a1c07e6 100644
--- a/TODO
+++ b/TODO
@@ -23,9 +23,6 @@
   .ad   -- re-enable adjustment without changing the mode
   Adjustment mode is ignored while in no-fill mode (.nf).
 
-- .cc (change control character) occurs in sqlite3(1)
-  reported by espie@  Sat, 14 Apr 2012 15:35:38 +0200
-
 - .it (line traps) occur in mysql(1), yasm_arch(7)
   generated by DocBook XSL Stylesheets v1.71.1 <http://docbook.sf.net/>
   reported by brad@  Sat, 15 Jan 2011 15:48:18 -0500
diff --git a/libmandoc.h b/libmandoc.h
index 7bcf41e1..94eae400 100644
--- a/libmandoc.h
+++ b/libmandoc.h
@@ -47,7 +47,6 @@ void		 mandoc_vmsg(enum mandocerr, struct mparse *,
 char		*mandoc_getarg(struct mparse *, char **, int, int *);
 char		*mandoc_normdate(struct mparse *, char *, int, int);
 int		 mandoc_eos(const char *, size_t, int);
-int		 mandoc_getcontrol(const char *, int *);
 int		 mandoc_strntoi(const char *, size_t, int);
 const char	*mandoc_a2msec(const char*);
 
@@ -77,6 +76,8 @@ int		 roff_regisset(const struct roff *, enum regs);
 unsigned int	 roff_regget(const struct roff *, enum regs);
 void		 roff_regunset(struct roff *, enum regs);
 char		*roff_strdup(const struct roff *, const char *);
+int		 roff_getcontrol(const struct roff *, 
+			const char *, int *);
 #if 0
 char		 roff_eqndelim(const struct roff *);
 void		 roff_openeqn(struct roff *, const char *, 
diff --git a/man.c b/man.c
index 016c2167..caef76f5 100644
--- a/man.c
+++ b/man.c
@@ -131,7 +131,7 @@ man_parseln(struct man *m, int ln, char *buf, int offs)
 
 	assert( ! (MAN_HALT & m->flags));
 
-	return (mandoc_getcontrol(buf, &offs) ?
+	return (roff_getcontrol(m->roff, buf, &offs) ?
 			man_pmacro(m, ln, buf, offs) : 
 			man_ptext(m, ln, buf, offs));
 }
diff --git a/mandoc.c b/mandoc.c
index 6c4eab6e..55419dc1 100644
--- a/mandoc.c
+++ b/mandoc.c
@@ -604,32 +604,6 @@ mandoc_eos(const char *p, size_t sz, int enclosed)
 }
 
 /*
- * Find out whether a line is a macro line or not.  If it is, adjust the
- * current position and return one; if it isn't, return zero and don't
- * change the current position.
- */
-int
-mandoc_getcontrol(const char *cp, int *ppos)
-{
-	int		pos;
-
-	pos = *ppos;
-
-	if ('\\' == cp[pos] && '.' == cp[pos + 1])
-		pos += 2;
-	else if ('.' == cp[pos] || '\'' == cp[pos])
-		pos++;
-	else
-		return(0);
-
-	while (' ' == cp[pos] || '\t' == cp[pos])
-		pos++;
-
-	*ppos = pos;
-	return(1);
-}
-
-/*
  * Convert a string to a long that may not be <0.
  * If the string is invalid, or is less than 0, return -1.
  */
diff --git a/mdoc.c b/mdoc.c
index f3cf256e..b32614f3 100644
--- a/mdoc.c
+++ b/mdoc.c
@@ -302,7 +302,7 @@ mdoc_parseln(struct mdoc *m, int ln, char *buf, int offs)
 			m->flags &= ~MDOC_SYNOPSIS;
 	}
 
-	return(mandoc_getcontrol(buf, &offs) ?
+	return(roff_getcontrol(m->roff, buf, &offs) ?
 			mdoc_pmacro(m, ln, buf, offs) :
 			mdoc_ptext(m, ln, buf, offs));
 }
diff --git a/roff.7 b/roff.7
index 31932803..44bc4e93 100644
--- a/roff.7
+++ b/roff.7
@@ -417,6 +417,18 @@ The syntax of this request is the same as that of
 It is currently ignored by
 .Xr mandoc 1 ,
 as are its children.
+.Ss \&cc
+Changes the control character.
+Its syntax is as follows:
+.Bd -literal -offset indent
+.Pf . Cm \&cc Op Ar c
+.Ed
+.Pp
+If
+.Ar c
+is not specified, the control character is reset to
+.Sq \&. .
+Trailing characters are ignored.
 .Ss \&de
 Define a
 .Nm
diff --git a/roff.c b/roff.c
index 4f0a392a..0b33a3dc 100644
--- a/roff.c
+++ b/roff.c
@@ -39,6 +39,7 @@ enum	rofft {
 	ROFF_am,
 	ROFF_ami,
 	ROFF_am1,
+	ROFF_cc,
 	ROFF_de,
 	ROFF_dei,
 	ROFF_de1,
@@ -105,6 +106,7 @@ struct	roff {
 	struct mparse	*parse; /* parse point */
 	struct roffnode	*last; /* leaf of stack */
 	enum roffrule	 rstack[RSTACK_MAX]; /* stack of !`ie' rules */
+	char		 control; /* control character */
 	int		 rstackpos; /* position in rstack */
 	struct reg	 regs[REG__MAX];
 	struct roffkv	*strtab; /* user-defined strings & macros */
@@ -169,6 +171,7 @@ static	enum rofferr	 roff_block(ROFF_ARGS);
 static	enum rofferr	 roff_block_text(ROFF_ARGS);
 static	enum rofferr	 roff_block_sub(ROFF_ARGS);
 static	enum rofferr	 roff_cblock(ROFF_ARGS);
+static	enum rofferr	 roff_cc(ROFF_ARGS);
 static	enum rofferr	 roff_ccond(ROFF_ARGS);
 static	enum rofferr	 roff_cond(ROFF_ARGS);
 static	enum rofferr	 roff_cond_text(ROFF_ARGS);
@@ -215,6 +218,7 @@ static	struct roffmac	 roffs[ROFF_MAX] = {
 	{ "am", roff_block, roff_block_text, roff_block_sub, 0, NULL },
 	{ "ami", roff_block, roff_block_text, roff_block_sub, 0, NULL },
 	{ "am1", roff_block, roff_block_text, roff_block_sub, 0, NULL },
+	{ "cc", roff_cc, NULL, NULL, 0, NULL },
 	{ "de", roff_block, roff_block_text, roff_block_sub, 0, NULL },
 	{ "dei", roff_block, roff_block_text, roff_block_sub, 0, NULL },
 	{ "de1", roff_block, roff_block_text, roff_block_sub, 0, NULL },
@@ -392,6 +396,7 @@ roff_reset(struct roff *r)
 
 	roff_free1(r);
 
+	r->control = 0;
 	memset(&r->regs, 0, sizeof(struct reg) * REG__MAX);
 
 	for (i = 0; i < PREDEFS_MAX; i++) 
@@ -611,7 +616,7 @@ roff_parseln(struct roff *r, int ln, char **bufp,
 	assert(ROFF_CONT == e);
 
 	ppos = pos;
-	ctl = mandoc_getcontrol(*bufp, &pos);
+	ctl = roff_getcontrol(r, *bufp, &pos);
 
 	/*
 	 * First, if a scope is open and we're not a macro, pass the
@@ -1363,6 +1368,23 @@ roff_TS(ROFF_ARGS)
 
 /* ARGSUSED */
 static enum rofferr
+roff_cc(ROFF_ARGS)
+{
+	const char	*p;
+
+	p = *bufp + pos;
+
+	if ('\0' == *p || '.' == (r->control = *p++))
+		r->control = 0;
+
+	if ('\0' != *p)
+		mandoc_msg(MANDOCERR_ARGCOUNT, r->parse, ln, ppos, NULL);
+
+	return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
 roff_tr(ROFF_ARGS)
 {
 	const char	*p, *first, *second;
@@ -1757,3 +1779,38 @@ roff_strdup(const struct roff *r, const char *p)
 	res[(int)ssz] = '\0';
 	return(res);
 }
+
+/*
+ * Find out whether a line is a macro line or not.  
+ * If it is, adjust the current position and return one; if it isn't,
+ * return zero and don't change the current position.
+ * If the control character has been set with `.cc', then let that grain
+ * precedence.
+ * This is slighly contrary to groff, where using the non-breaking
+ * control character when `cc' has been invoked will cause the
+ * non-breaking macro contents to be printed verbatim.
+ */
+int
+roff_getcontrol(const struct roff *r, const char *cp, int *ppos)
+{
+	int		pos;
+
+	pos = *ppos;
+
+	if (0 != r->control && cp[pos] == r->control)
+		pos++;
+	else if (0 != r->control)
+		return(0);
+	else if ('\\' == cp[pos] && '.' == cp[pos + 1])
+		pos += 2;
+	else if ('.' == cp[pos] || '\'' == cp[pos])
+		pos++;
+	else
+		return(0);
+
+	while (' ' == cp[pos] || '\t' == cp[pos])
+		pos++;
+
+	*ppos = pos;
+	return(1);
+}