cleanups

1 files changed, 28 insertions, 21 deletions

diff --git a/src/pnmcurve.c b/src/pnmcurve.c
index 770de44..d843251 100644
--- a/src/pnmcurve.c
+++ b/src/pnmcurve.c
@@ -29,9 +29,9 @@ main(int argc, char **argv) {
 	char *curve = NULL;
 	struct pnm in_pnm;
 	int channels = 0;
-	table_t *gTable[3];
+	table_t *table, *gTable[3];
 
-	while ((c = getopt(argc, argv, "rgbC:h")) != EOF) {
+	while ((c = getopt(argc, argv, "rgbc:h")) != EOF) {
 		switch (c) {  
 			case 'r':
 				channels |= RED;
@@ -42,7 +42,7 @@ main(int argc, char **argv) {
 			case 'b':
 				channels |= BLUE;
 				break;
-			case 'C':
+			case 'c':
 				curve = optarg;
 				break;
 
@@ -52,22 +52,24 @@ main(int argc, char **argv) {
 	}
 
 	if (readPnmHeader(stdin, &in_pnm) != 0) {
+		fprintf(stderr, "failed to read PNM file\n");
 		exit(1);
 	}
 
-	if (in_pnm.maxval == 255) {
-	} else if (in_pnm.maxval == 65535) {
-	} else {
+	if (in_pnm.maxval != 255 && in_pnm.maxval != 65535) {
 		fprintf(stderr, "unsupported PNM maxval %d\n", in_pnm.maxval);
 		exit(1);
 	}
 
 	if (curve) {
-		table_t *table;
-
 		if (channels == 0) channels = RED | GREEN | BLUE;
 
 		table = buildCurve(curve, in_pnm.maxval + 1, in_pnm.maxval);
+
+		if (!table) {
+			fprintf(stderr, "could not build table.\n");
+			exit(1);
+		}
 	
 		gTable[0] = channels & RED ? table : NULL;	
 		gTable[1] = channels & GREEN ? table : NULL;	
@@ -89,8 +91,8 @@ pam_transform(FILE *in_fp, FILE *out_fp,
 	unsigned char *buf = malloc(in_pnm->width * nbytes * 3);
 
 	for (c = 0; c < 3; c++) {
-		if (tables[c] && tables[c]->n < in_pnm->maxval) {
-			fprintf(stderr, "Table %d too small (%d)\n", c, tables[c]->n);
+		if (tables[c] && tables[c]->n <= in_pnm->maxval) {
+			fprintf(stderr, "table %d too small (%d)\n", c, tables[c]->n);
 			return 1;
 		}
 	}
@@ -114,10 +116,10 @@ pam_transform(FILE *in_fp, FILE *out_fp,
 
 					if (nbytes == 1) {
 						buf[i * 3 + c] = (unsigned char) tables[c]->value[val];
-					} else {
-						int v1 = tables[c]->value[val];
-						buf[(i * 3 + c) * 2] = (unsigned char) (v1 >> 8);
-						buf[(i * 3 + c) * 2 + 1] = (unsigned char) v1;
+					} else if (nbytes == 2) {
+						val = tables[c]->value[val];
+						buf[(i * 3 + c) * 2] = (unsigned char) (val >> 8);
+						buf[(i * 3 + c) * 2 + 1] = (unsigned char) val;
 					}
 				}
 			}
@@ -142,15 +144,15 @@ buildCurve(const char *ctrl_points, int resolution, int maxval) {
 	gsl_spline *spline;
 
 	while (pstr = strsep(&buf, ",")) {
-		if (n == MAX_CTRL) {
-			fprintf(stderr, "Maximum number of control points (%d) reached.\n",
+		if (n >= MAX_CTRL) {
+			fprintf(stderr, "maximum number of control points (%d) reached.\n",
 				MAX_CTRL);
 			break;
 		}
 
 		if (sscanf(pstr, "%lf:%lf", &X[n], &Y[n]) != 2 ||
 			X[n] < 0.0 || X[n] > 1.0 || Y[n] < 0.0 || Y[n] > 1.0) {
-			fprintf(stderr, "Could not parse control point %s.\n", pstr);
+			fprintf(stderr, "could not parse control point %s.\n", pstr);
 			free(buf);
 			return NULL;
 		}
@@ -160,6 +162,11 @@ buildCurve(const char *ctrl_points, int resolution, int maxval) {
 
 	free(buf);
 
+	if (n < 3) {
+		fprintf(stderr, "not enough control point specified.\n");
+		return NULL;
+	}
+
 	table = (table_t*) malloc(sizeof(table_t) + resolution * sizeof(short));
 	table->n = resolution;
 
@@ -170,11 +177,11 @@ buildCurve(const char *ctrl_points, int resolution, int maxval) {
 	for (i = 0; i < resolution; i++) {
 		double _x = (double) i / (resolution - 1);
 		double _y = gsl_spline_eval(spline, _x, acc);
-        double dval = _y * maxval + .5;
-        if (dval > maxval) dval = (double) maxval;
-        if (dval < 0) dval = 0;
+        double val = _y * maxval + 0.5;
+        if (val > maxval) val = (double) maxval;
+        if (val < 0) val = 0;
 
-        table->value[i] = (unsigned short) floor(dval);
+        table->value[i] = (unsigned short) floor(val);
 	}
 
 	gsl_spline_free(spline);