===================================================================
RCS file: /cvs/texi2mdoc/util.c,v
retrieving revision 1.16
retrieving revision 1.19
diff -u -p -r1.16 -r1.19
--- texi2mdoc/util.c	2015/02/25 15:50:56	1.16
+++ texi2mdoc/util.c	2015/02/28 13:16:44	1.19
@@ -1,4 +1,4 @@
-/*	$Id: util.c,v 1.16 2015/02/25 15:50:56 kristaps Exp $ */
+/*	$Id: util.c,v 1.19 2015/02/28 13:16:44 kristaps Exp $ */
 /*
  * Copyright (c) 2015 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -330,8 +330,11 @@ advance(struct texi *p, size_t *pos)
 			f->col = 0;
 		} else
 			f->col++;
-	} else
+	} else {
 		--f->insplice;
+		if (0 == f->insplice)
+			f->depth = 0;
+	}
 
 	(*pos)++;
 }
@@ -439,7 +442,7 @@ advanceto(struct texi *p, size_t *pos, size_t end)
 }
 
 static void
-texiexecmacro(struct texi *p, struct teximacro *m, size_t *pos)
+texiexecmacro(struct texi *p, struct teximacro *m, size_t sv, size_t *pos)
 {
 	size_t		  valsz, realsz, aasz, asz, 
 			   ssz, i, j, k, start, end;
@@ -447,17 +450,31 @@ texiexecmacro(struct texi *p, struct teximacro *m, siz
 	char		**args;
 	const char	 *cp;
 
+	/* Disregard empty macros. */
+	if (0 == (valsz = realsz = strlen(m->value)))
+		return;
+
+	/*
+	 * This is important: it protect us from macros that invoke more
+	 * macros, possibly going on infinitely.
+	 * We use "sv" instead of the current position because we might
+	 * be invoked at the end of the macro (i.e., insplice == 0).
+	 * The "sv" value was initialised at the start of the macro.
+	 */
+	if (sv > 0)
+		if (++p->files[p->filepos].depth > 64)
+			texierr(p, "maximium recursive depth");
+
 	args = argparse(p, pos, &asz, m->argsz);
 	if (asz != m->argsz)
 		texiwarn(p, "invalid macro argument length");
 	aasz = asz < m->argsz ? asz : m->argsz;
 
 	if (0 == aasz) {
-		texisplice(p, m->value, strlen(m->value), pos);
+		texisplice(p, m->value, valsz, pos);
 		return;
 	}
 
-	valsz = realsz = strlen(m->value);
 	val = strdup(m->value);
 
 	for (i = j = 0; i < realsz; i++) {
@@ -574,7 +591,7 @@ parseword(struct texi *p, size_t *pos, char extra)
  * index after the command name.
  */
 enum texicmd
-texicmd(struct texi *p, size_t pos, size_t *end, struct teximacro **macro)
+texicmd(const struct texi *p, size_t pos, size_t *end, struct teximacro **macro)
 {
 	size_t	 i, len, toksz;
 
@@ -653,7 +670,7 @@ texicmd(struct texi *p, size_t pos, size_t *end, struc
 int
 parsearg(struct texi *p, size_t *pos, size_t num)
 {
-	size_t		  end;
+	size_t		  end, sv;
 	enum texicmd	  cmd;
 	struct teximacro *macro;
 
@@ -684,10 +701,11 @@ parsearg(struct texi *p, size_t *pos, size_t num)
 			continue;
 		}
 
+		sv = p->files[p->filepos - 1].insplice;
 		cmd = texicmd(p, *pos, &end, &macro);
 		advanceto(p, pos, end);
 		if (NULL != macro)
-			texiexecmacro(p, macro, pos);
+			texiexecmacro(p, macro, sv, pos);
 		if (TEXICMD__MAX == cmd) 
 			continue;
 		if (NULL != texitoks[cmd].fp)
@@ -701,9 +719,9 @@ parsearg(struct texi *p, size_t *pos, size_t num)
  * This will stop in the event of EOF or if we're not at a bracket.
  */
 void
-parsebracket(struct texi *p, size_t *pos)
+parsebracket(struct texi *p, size_t *pos, int dostack)
 {
-	size_t		  end;
+	size_t		  end, sv, stack;
 	enum texicmd	  cmd;
 	struct teximacro *macro;
 
@@ -714,12 +732,25 @@ parsebracket(struct texi *p, size_t *pos)
 		return;
 	advance(p, pos);
 
+	stack = 0;
 	while ((*pos = advancenext(p, pos)) < BUFSZ(p)) {
 		switch (BUF(p)[*pos]) {
 		case ('}'):
+			if (stack > 0) {
+				stack--;
+				advance(p, pos);
+				texiputchar(p, '}');
+				continue;
+			}
 			advance(p, pos);
 			return;
 		case ('{'):
+			if (dostack) {
+				stack++;
+				advance(p, pos);
+				texiputchar(p, '{');
+				continue;
+			}
 			if (0 == p->ign)
 				texiwarn(p, "unexpected \"{\"");
 			advance(p, pos);
@@ -731,10 +762,11 @@ parsebracket(struct texi *p, size_t *pos)
 			continue;
 		}
 
+		sv = p->files[p->filepos - 1].insplice;
 		cmd = texicmd(p, *pos, &end, &macro);
 		advanceto(p, pos, end);
 		if (NULL != macro)
-			texiexecmacro(p, macro, pos);
+			texiexecmacro(p, macro, sv, pos);
 		if (TEXICMD__MAX == cmd) 
 			continue;
 		if (NULL != texitoks[cmd].fp)
@@ -750,7 +782,7 @@ parsebracket(struct texi *p, size_t *pos)
 void
 parseeoln(struct texi *p, size_t *pos)
 {
-	size_t		  end;
+	size_t		  end, sv;
 	enum texicmd	  cmd;
 	struct teximacro *macro;
 
@@ -779,10 +811,11 @@ parseeoln(struct texi *p, size_t *pos)
 			continue;
 		}
 
+		sv = p->files[p->filepos - 1].insplice;
 		cmd = texicmd(p, *pos, &end, &macro);
 		advanceto(p, pos, end);
 		if (NULL != macro)
-			texiexecmacro(p, macro, pos);
+			texiexecmacro(p, macro, sv, pos);
 		if (TEXICMD__MAX == cmd) 
 			continue;
 		if (NULL != texitoks[cmd].fp)
@@ -794,13 +827,30 @@ parseeoln(struct texi *p, size_t *pos)
 }
 
 /*
+ * Peek to see if there's a command after subsequent whitespace.
+ * If so, return the macro identifier.
+ * This DOES NOT work with user-defined macros.
+ */
+enum texicmd
+peekcmd(const struct texi *p, size_t pos)
+{
+	size_t		end;
+
+	while (pos < BUFSZ(p) && ismspace(BUF(p)[pos]))
+		pos++;
+	if (pos == BUFSZ(p) || '@' != BUF(p)[pos])
+		return(TEXICMD__MAX);
+	return(texicmd(p, pos, &end, NULL));
+}
+
+/*
  * Parse a single word or command.
  * This will return immediately at the EOF.
  */
 static void
 parsesingle(struct texi *p, size_t *pos)
 {
-	size_t		  end;
+	size_t		  end, sv;
 	enum texicmd	  cmd;
 	struct teximacro *macro;
 
@@ -825,10 +875,11 @@ parsesingle(struct texi *p, size_t *pos)
 		return;
 	}
 
+	sv = p->files[p->filepos - 1].insplice;
 	cmd = texicmd(p, *pos, &end, &macro);
 	advanceto(p, pos, end);
 	if (NULL != macro)
-		texiexecmacro(p, macro, pos);
+		texiexecmacro(p, macro, sv, pos);
 	if (TEXICMD__MAX == cmd) 
 		return;
 	if (NULL != texitoks[cmd].fp)
@@ -853,7 +904,7 @@ parselinearg(struct texi *p, size_t *pos)
 	}
 
 	if (*pos < BUFSZ(p) && '{' == BUF(p)[*pos])
-		parsebracket(p, pos);
+		parsebracket(p, pos, 0);
 	else if (*pos < BUFSZ(p) && '\n' != BUF(p)[*pos])
 		parsesingle(p, pos);
 	else
@@ -905,7 +956,7 @@ texisplice(struct texi *p, const char *buf, size_t sz,
 void
 parseto(struct texi *p, size_t *pos, const char *endtoken)
 {
-	size_t		  end;
+	size_t		  end, sv;
 	enum texicmd	  cmd;
 	size_t		  endtoksz;
 	struct teximacro *macro;
@@ -932,6 +983,7 @@ parseto(struct texi *p, size_t *pos, const char *endto
 			continue;
 		}
 
+		sv = p->files[p->filepos - 1].insplice;
 		cmd = texicmd(p, *pos, &end, &macro);
 		advanceto(p, pos, end);
 		if (TEXICMD_END == cmd) {
@@ -952,7 +1004,7 @@ parseto(struct texi *p, size_t *pos, const char *endto
 			continue;
 		} 
 		if (NULL != macro)
-			texiexecmacro(p, macro, pos);
+			texiexecmacro(p, macro, sv, pos);
 		if (TEXICMD__MAX == cmd) 
 			continue;
 		if (NULL != texitoks[cmd].fp) 
@@ -1209,6 +1261,9 @@ argparse(struct texi *p, size_t *pos, size_t *argsz, s
 	args = NULL;
 	*argsz = 0;
 
+	if (*pos == BUFSZ(p))
+		return(args);
+
 	if ('{' != BUF(p)[*pos] && hint) {
 		/*
 		 * Special case: if we encounter an unbracketed argument
@@ -1234,6 +1289,8 @@ argparse(struct texi *p, size_t *pos, size_t *argsz, s
 		return(args);
 	} else if ('{' != BUF(p)[*pos])
 		return(args);
+
+	assert('{' == BUF(p)[*pos]);
 
 	/* Parse til the closing '}', putting into the array. */
 	advance(p, pos);