From 4fd8c77456f73fb6b30d4ed7125e3990e70a6eed Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sat, 14 Apr 2018 14:51:55 +0300
Subject: [PATCH] Refactor option processing

Conversion code was moved to utility functions.  Numeric values are now
checked for being in the proper range and not having garbage at the end.
---
 ttf2png.c | 134 ++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 84 insertions(+), 50 deletions(-)

diff --git a/ttf2png.c b/ttf2png.c
index e8d794c..ae559b1 100644
--- a/ttf2png.c
+++ b/ttf2png.c
@@ -62,6 +62,9 @@ typedef struct sFont
 } Font;
 
 void usage(void);
+int convert_numeric_option(char, int);
+void convert_code_point_range(char, int *, int *);
+void convert_size(char, int *, int *);
 unsigned round_to_pot(unsigned);
 void *alloc_image_data(size_t, size_t);
 int init_font(Font *, FT_Face, unsigned, unsigned, int);
@@ -108,63 +111,19 @@ int main(int argc, char **argv)
 
 	while((i = getopt(argc, argv, "r:s:l:c:o:atvh?ed:pim:n:")) != -1)
 	{
-		char *ptr;
-		int temp;
 		switch(i)
 		{
 		case 'r':
-			if(!strcmp(optarg, "all"))
-			{
-				begin = 0;
-				end = 0x110000;
-			}
-			else
-			{
-				if(!isdigit(optarg[0]))
-					temp = -1;
-				else
-				{
-					temp = strtol(optarg, &ptr, 0);
-					if(ptr[0]!=',' || !isdigit(ptr[1]))
-						temp = -1;
-				}
-				if(temp<0)
-				{
-					printf("Not a valid range: %s\n", optarg);
-					exit(1);
-				}
-				else
-				{
-					begin = temp;
-					end = strtol(ptr+1, NULL, 0);
-				}
-			}
+			convert_code_point_range('r', &begin, &end);
 			break;
 		case 's':
-			size = strtol(optarg, NULL, 0);
+			size = convert_numeric_option('s', 1);
 			break;
 		case 'l':
-			cpl = strtol(optarg, NULL, 0);
+			cpl = convert_numeric_option('l', 1);
 			break;
 		case 'c':
-			if(!strcmp(optarg, "auto"))
-			{
-				cellw = 0;
-				cellh = 0;
-			}
-			else if(!strcmp(optarg, "autorect"))
-			{
-				cellw = 0;
-				cellh = 1;
-			}
-			else
-			{
-				cellw = strtol(optarg, &ptr, 0);
-				if(ptr[0]=='x' && isdigit(ptr[1]))
-					cellh = strtol(ptr+1, NULL, 0);
-				else
-					cellh = cellw;
-			}
+			convert_size('c', &cellw, &cellh);
 			break;
 		case 'o':
 			out_fn = optarg;
@@ -195,10 +154,10 @@ int main(int argc, char **argv)
 			invert = 1;
 			break;
 		case 'm':
-			margin = strtol(optarg, NULL, 0);
+			margin = convert_numeric_option('m', 0);
 			break;
 		case 'n':
-			padding = strtol(optarg, NULL, 0);
+			padding = convert_numeric_option('n', 0);
 			break;
 		}
 	}
@@ -305,6 +264,81 @@ void usage(void)
 		"  -h  Print this message\n");
 }
 
+int convert_numeric_option(char opt, int min_value)
+{
+	int value;
+	char *ptr;
+
+	value = strtol(optarg, &ptr, 0);
+	if(value<min_value || *ptr)
+	{
+		printf("Invalid option argument in -%c %s\n", opt, optarg);
+		exit(1);
+	}
+
+	return value;
+}
+
+void convert_code_point_range(char opt, int *begin, int *end)
+{
+	char *ptr;
+
+	if(!strcmp(optarg, "all"))
+	{
+		*begin = 0;
+		*end = 0x10FFFF;
+		return;
+	}
+
+	*begin = strtol(optarg, &ptr, 0);
+	if(*begin>0 && *ptr==',')
+	{
+		*end = strtol(ptr+1, &ptr, 0);
+		if(*end>0 && !*ptr)
+			return;
+	}
+
+	printf("Invalid option argument in -%c %s\n", opt, optarg);
+	exit(1);
+}
+
+void convert_size(char opt, int *width, int *height)
+{
+	char *ptr;
+
+	if(!strcmp(optarg, "auto"))
+	{
+		*width = 0;
+		*height = 0;
+		return;
+	}
+	else if(!strcmp(optarg, "autorect"))
+	{
+		*width = 0;
+		*height = 1;
+		return;
+	}
+
+	*width = strtol(optarg, &ptr, 0);
+	if(*width>0)
+	{
+		if(*ptr=='x')
+		{
+			*height = strtol(ptr+1, &ptr, 0);
+			if(*height>0 && !*ptr)
+				return;
+		}
+		else if(!*ptr)
+		{
+			*height = *width;
+			return;
+		}
+	}
+
+	printf("Invalid option argument in -%c %s\n", opt, optarg);
+	exit(1);
+}
+
 unsigned round_to_pot(unsigned n)
 {
 	n -= 1;
-- 
2.43.0