Clarify what members may be NULL or not in calculating widths. Make

sure signedness is correct.  Verify that layouts MUST exit for data
cells.

4 files changed, 27 insertions, 23 deletions

diff --git a/mandoc.h b/mandoc.h
index f32db5a4..72782eb1 100644
--- a/mandoc.h
+++ b/mandoc.h
@@ -200,7 +200,7 @@ enum	tbl_cellt {
 struct	tbl_cell {
 	struct tbl_cell	 *next;
 	enum tbl_cellt	  pos;
-	int		  spacing;
+	size_t		  spacing;
 	int		  flags;
 #define	TBL_CELL_TALIGN	 (1 << 0) /* t, T */
 #define	TBL_CELL_BALIGN	 (1 << 1) /* d, D */
@@ -222,12 +222,12 @@ struct	tbl_row {
 };
 
 enum	tbl_datt {
-	TBL_DATA_NONE,
-	TBL_DATA_DATA,
-	TBL_DATA_HORIZ,
-	TBL_DATA_DHORIZ,
-	TBL_DATA_NHORIZ,
-	TBL_DATA_NDHORIZ
+	TBL_DATA_NONE, /* has no data */
+	TBL_DATA_DATA, /* consists of data/string */
+	TBL_DATA_HORIZ, /* horizontal line */
+	TBL_DATA_DHORIZ, /* double-horizontal line */
+	TBL_DATA_NHORIZ, /* squeezed horizontal line */
+	TBL_DATA_NDHORIZ /* squeezed double-horizontal line */
 };
 
 /*
@@ -235,10 +235,10 @@ enum	tbl_datt {
  * string value that's in the cell.  The rest is layout.
  */
 struct	tbl_dat {
-	struct tbl_cell	 *layout; /* layout cell: CAN BE NULL */
+	struct tbl_cell	 *layout; /* layout cell */
 	int		  spans; /* how many spans follow */
 	struct tbl_dat	 *next;
-	char		 *string;
+	char		 *string; /* data (NULL if not TBL_DATA_DATA) */
 	enum tbl_datt	  pos;
 };
 
@@ -254,7 +254,7 @@ enum	tbl_spant {
 struct	tbl_span {
 	struct tbl	 *tbl;
 	struct tbl_head	 *head;
-	struct tbl_row	 *layout; /* layout row: CAN BE NULL */
+	struct tbl_row	 *layout; /* layout row */
 	struct tbl_dat	 *first;
 	struct tbl_dat	 *last;
 	int		  flags;
diff --git a/out.c b/out.c
index 1a647922..79a0c4d2 100644
--- a/out.c
+++ b/out.c
@@ -464,6 +464,7 @@ tblcalc_literal(struct rofftbl *tbl, struct roffcol *col,
 		const struct tbl_dat *dp)
 {
 	size_t		 sz, bufsz, spsz;
+	const char	*str;
 
 	/* 
 	 * Calculate our width and use the spacing, with a minimum
@@ -471,9 +472,11 @@ tblcalc_literal(struct rofftbl *tbl, struct roffcol *col,
 	 * either side, while right/left get a single adjacent space).
 	 */
 
-	sz = bufsz = spsz = 0;
-	if (dp->string)
-		sz = (*tbl->slen)(dp->string, tbl->arg);
+	bufsz = spsz = 0;
+	str = dp->string ? dp->string : "";
+	sz = (*tbl->slen)(str, tbl->arg);
+
+	/* FIXME: TBL_DATA_HORIZ et al.? */
 
 	assert(dp->layout);
 	switch (dp->layout->pos) {
@@ -502,9 +505,9 @@ tblcalc_number(struct rofftbl *tbl, struct roffcol *col,
 		const struct tbl *tp, const struct tbl_dat *dp)
 {
 	int 		 i;
-	size_t		 sz, psz, ssz, d, max;
-	char		*cp;
+	size_t		 sz, psz, ssz, d;
 	const char	*str;
+	char		*cp;
 	char		 buf[2];
 
 	/*
@@ -516,11 +519,11 @@ tblcalc_number(struct rofftbl *tbl, struct roffcol *col,
 	 * Finally, re-assign the stored values.
 	 */
 
-	str = dp && dp->string ? dp->string : "";
-	max = dp && dp->layout ? dp->layout->spacing : 0;
-
+	str = dp->string ? dp->string : "";
 	sz = (*tbl->slen)(str, tbl->arg);
 
+	/* FIXME: TBL_DATA_HORIZ et al.? */
+
 	buf[0] = tp->decimal;
 	buf[1] = '\0';
 
@@ -556,8 +559,8 @@ tblcalc_number(struct rofftbl *tbl, struct roffcol *col,
 
 	/* Adjust for stipulated width. */
 
-	if (col->width < max)
-		col->width = max;
+	if (col->width < dp->layout->spacing)
+		col->width = dp->layout->spacing;
 }
 
 
diff --git a/tbl_data.c b/tbl_data.c
index 6172bd4a..b4da8fcd 100644
--- a/tbl_data.c
+++ b/tbl_data.c
@@ -188,8 +188,6 @@ tbl_data(struct tbl_node *tbl, int ln, const char *p)
 	 * If there's no last parsed span, use the first row.  Lastly,
 	 * if the last span was a horizontal line, use the same layout
 	 * (it doesn't "consume" the layout).
-	 *
-	 * In the end, this can be NULL!
 	 */
 
 	if (tbl->last_span) {
@@ -198,11 +196,14 @@ tbl_data(struct tbl_node *tbl, int ln, const char *p)
 			rp = tbl->last_span->layout->next;
 		else
 			rp = tbl->last_span->layout;
+
 		if (NULL == rp)
 			rp = tbl->last_span->layout;
 	} else
 		rp = tbl->first_row;
 
+	assert(rp);
+
 	dp = mandoc_calloc(1, sizeof(struct tbl_span));
 	dp->tbl = &tbl->opts;
 	dp->layout = rp;
diff --git a/tbl_layout.c b/tbl_layout.c
index ea93f645..25b77e1c 100644
--- a/tbl_layout.c
+++ b/tbl_layout.c
@@ -122,7 +122,7 @@ mod:
 		}
 
 		*pos += i;
-		cp->spacing = atoi(buf);
+		cp->spacing = (size_t)atoi(buf);
 
 		goto mod;
 		/* NOTREACHED */