--- ray/src/util/cmatrix.c	2020/03/26 16:56:10	2.27
+++ ray/src/util/cmatrix.c	2021/01/15 17:22:23	2.30
@@ -1,5 +1,5 @@
 #ifndef lint
-static const char RCSid[] = "$Id: cmatrix.c,v 2.27 2020/03/26 16:56:10 greg Exp $";
+static const char RCSid[] = "$Id: cmatrix.c,v 2.30 2021/01/15 17:22:23 greg Exp $";
 #endif
 /*
  * Color matrix routines.
@@ -33,7 +33,7 @@ cm_alloc(int nrows, int ncols)
 	if ((nrows <= 0) | (ncols <= 0))
 		error(USER, "attempt to create empty matrix");
 	cm = (CMATRIX *)malloc(sizeof(CMATRIX) +
-				sizeof(COLOR)*(nrows*ncols - 1));
+				sizeof(COLOR)*((size_t)nrows*ncols - 1));
 	if (!cm)
 		error(SYSTEM, "out of memory in cm_alloc()");
 	cm->nrows = nrows;
@@ -65,9 +65,9 @@ cm_resize(CMATRIX *cm, int nrows)
 		cm_free(cm);
 		return(NULL);
 	}
-	old_size = sizeof(CMATRIX) + sizeof(COLOR)*(cm->nrows*cm->ncols - 1);
+	old_size = sizeof(CMATRIX) + sizeof(COLOR)*((size_t)cm->nrows*cm->ncols - 1);
 	adjacent_ra_sizes(ra_bounds, old_size);
-	new_size = sizeof(CMATRIX) + sizeof(COLOR)*(nrows*cm->ncols - 1);
+	new_size = sizeof(CMATRIX) + sizeof(COLOR)*((size_t)nrows*cm->ncols - 1);
 	if (nrows < cm->nrows ? new_size <= ra_bounds[0] :
 				new_size > ra_bounds[1]) {
 		adjacent_ra_sizes(ra_bounds, new_size);
@@ -181,10 +181,6 @@ cm_load_rgbe(FILE *fp, int nrows, int ncols, COLOR sca
 	CMATRIX	*cm;
 	COLORV	*mp;
 						/* header already loaded */
-	if ((nrows <= 0) | (ncols <= 0) && !fscnresolu(&ncols, &nrows, fp)) {
-		error(USER, "bad picture resolution string");
-		return(NULL);
-	}
 	cm = cm_alloc(nrows, ncols);
 	if (!cm)
 		return(NULL);
@@ -242,9 +238,9 @@ cm_load(const char *inspec, int nrows, int ncols, int 
 		char	*err = cm_getheader(&dtype, &nrows, &ncols, &swap, scale, fp);
 		if (err)
 			error(USER, err);
-		if (ncols <= 0)
-			error(USER, "unspecified number of columns");
 	}
+	if (ncols <= 0 && !fscnresolu(&ncols, &nrows, fp))
+		error(USER, "unspecified number of columns");
 	switch (dtype) {
 	case DTascii:
 	case DTfloat:
@@ -487,6 +483,7 @@ cm_write(const CMATRIX *cm, int dtype, FILE *fp)
 	static const char	tabEOL[2] = {'\t','\n'};
 	const COLORV		*mp;
 	int			r, c;
+	size_t			n, rv;
 
 	if (!cm)
 		return(0);
@@ -502,18 +499,18 @@ cm_write(const CMATRIX *cm, int dtype, FILE *fp)
 	case DTfloat:
 	case DTdouble:
 		if (sizeof(COLOR) == cm_elem_size[dtype]) {
-			r = cm->ncols*cm->nrows;
-			while (r > 0) {
-				c = putbinary(mp, sizeof(COLOR), r, fp);
-				if (c <= 0)
+			n = (size_t)cm->ncols*cm->nrows;
+			while (n > 0) {
+				rv = fwrite(mp, sizeof(COLOR), n, fp);
+				if (rv <= 0)
 					return(0);
-				mp += 3*c;
-				r -= c;
+				mp += 3*rv;
+				n -= rv;
 			}
 		} else if (dtype == DTdouble) {
 			double	dc[3];
-			r = cm->ncols*cm->nrows;
-			while (r--) {
+			n = (size_t)cm->ncols*cm->nrows;
+			while (n--) {
 				copycolor(dc, mp);
 				if (putbinary(dc, sizeof(double), 3, fp) != 3)
 					return(0);
@@ -521,8 +518,8 @@ cm_write(const CMATRIX *cm, int dtype, FILE *fp)
 			}
 		} else /* dtype == DTfloat */ {
 			float	fc[3];
-			r = cm->ncols*cm->nrows;
-			while (r--) {
+			n = (size_t)cm->ncols*cm->nrows;
+			while (n--) {
 				copycolor(fc, mp);
 				if (putbinary(fc, sizeof(float), 3, fp) != 3)
 					return(0);