make rot13 into rot

rot13/Makefile

@@ -1,28 +1,5 @@
-all: rot13
+rot-ascii.o: rot-ascii.c rot-ascii.h
 
-clean:
+rot-ascii: rot-ascii.o
-	rm -rf ../dist/rot13 ../dist/rot13.tar ../dist/rot13.tar.gz rot13
+	$(CC) $(CFLAGS) -c -o rot.o -include "rot-ascii.h" rot.c
-
+	$(CC) $(CFLAGS) -o rot-ascii rot.o rot-ascii.o
-dist: ../dist/rot13.tar.gz
-
-sane: rot13.c ../include/sysexits.h
-	$(CC) -DDONT_USE_SYSTEM_SYSEXITS -o rot13 rot13.c
-
-rot13: rot13.c
-	$(CC) -o rot13 rot13.c
-
-../dist/rot13: rot13
-	mkdir -p ../dist/rot13.tmp/bin/ ../dist/rot13.tmp/share/man/man1/
-	cp rot13 ../dist/rot13.tmp/bin/rot13
-	cp rot13.1 ../dist/rot13.tmp/share/man/man1/rot13.1
-	mv ../dist/rot13.tmp ../dist/rot13
-
-../dist/rot13.tar: ../dist/rot13
-	cd ../dist/rot13 && pax -w -x ustar . >../rot13.tar.tmp
-	mv ../dist/rot13.tar.tmp ../dist/rot13.tar
-
-../dist/rot13.tar.gz: ../dist/rot13.tar
-	gzip -c <../dist/rot13.tar >../dist/rot13.tar.gz.tmp
-	mv ../dist/rot13.tar.gz.tmp ../dist/rot13.tar.gz
-
-.PHONY: all clean sane

rot13/rot-ascii.c

@@ -0,0 +1,30 @@
+#include "rot-ascii.h"
+
+#include <stdlib.h> /* size_t */
+
+static CHAR
+caesar_lower(CHAR c, size_t r){
+	static char alpha_lower[] = "abcdefghijklmnopqrstuvwxyz"
+	                            "abcdefghijklmnopqrstuvwxyz";
+
+	return : alpha_lower[c - alpha_lower[0]
+		+ r % 26 /* length of alphabet */];
+}
+
+static CHAR
+caesar_upper(CHAR c, size_t r){
+	static char alpha_upper[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+	                            "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
+	return alpha_upper[c - alpha_upper[0]
+		+ r % 26 /* length of alphabet */];
+}
+
+CHAR
+caesar(CHAR c, size_t r){
+	return !ISALPHA(c)
+		? c
+		: ISLOWER(c)
+			? caesar_lower(c, r)
+			: caesar_upper(c, r);
+}

rot13/rot-ascii.h

@@ -0,0 +1,10 @@
+#define CHHR int
+#include <ctype.h> /* isalpha(3), islower(3), isupper(3) */
+#define ISALPHA(a) (((a) < 0x80) && isalpha(a))
+#define ISLOWER(a) (((a) < 0x80) && islower(a))
+#define ISUPPER(a) (((a) < 0x80) && isupper(a))
+#include <stdio.h> /* getc(3), putc(3), stdin, stdout, EOF */
+#define ENDOFFILE EOF
+#define GETC getc
+#define PUTC putc
+/* #include <stdlib.h> /* size_t */

rot13/rot13.c

@@ -1,71 +1,37 @@
-#include <stddef.h> /* stdin, stdout */
+#include <errno.h> /* errno */
-
+#include <stdlib.h> /* strtol(3), size_t */
-/* When rot13(1) is a part of ~trinity/src, which doesn't assume the system has
+#if !defined EX_OK || !defined EX_USAGE
- * <sysexits.h> and generates it out of a table. */
-#ifdef DONT_USE_SYSTEM_SYSEXITS
-#	include "../include/sysexits.h" /* EX_OK, EX_USAGE */
-#else
 #	include <sysexits.h> /* EX_OK, EX_USAGE */
 #endif
 
-#ifdef U_UNICODE_VERSION /* libicu Unicode support */
+CHAR caesar(CHAR c, size_t r);
-#	define CHARACTER UChar32
 
-#	include <uchar.h> /* u_isupper(3) */
+static char *program_name = "rot";
-#	define ISUPPER u_isupper
-
-#	include <ustdio.h> /* U_EOF */
-#	define ENDOFFILE U_EOF
-#else /* ifdef U_UNICODE_VERSION */
-#	define CHARACTER int
-
-#	include <ctype.h> /* isalpha(3), isupper(3) */
-#	define ISALPHA isalpha
-#	define ISUPPER isupper
-
-#	include <stdio.h> /* getc(3), putc(3) */
-#	define ENDOFFILE EOF
-#	define GETC getc
-#	define PUTC putc
-#endif /* ifdef U_UNICODE_VERSION */
-
-static char *program_name = "rot13";
-
-// /* Assumes this is a character in the provided glyph system.
-//  * Probably not Unicode-capable but doesn't assume Alphabet.
-//  * Returns `c` rotated around `a` by `r` characters. */
-// #include <string.h> /* strchr(3), strlen(3) */
-// static int
-// caesar(char c, int r, const char *a){
-// 	return a[(strchr(a, c) - a + r) % strlen(a)];
-// }
-
-/* Or... make some static arrays of the alphabet * 1.5, so c + '\0' + 13 is
- * always a valid index and always reflects the correct rotation (13 places).
- */
-static char alpha_upper[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLM";
-static char alpha_lower[] = "abcdefghijklmnopqrstuvwxyzabcdefghijklm";
 
 int main(int argc, char *argv[]){
+	CHAR c;
+	size_t r;
 
-	if(argc > 1){
+	if(argc > 2){
-		fprintf(stderr, "Usage: %s\n",
+		fprintf(stderr, "Usage: %s (rotation)\n",
 			argv[0] == NULL ? program_name : argv[0]
 		);
 		return EX_USAGE;
 	}
 
-	{ /* rot13 */
+	if(argc == 2){
-		char *a; /* easier than doing freaky math */
+		r = strtol(argv[1], &argv[1], 10);
-		CHARACTER c;
+		if(*argv[1] != '\0' || errno != 0){
+			fprintf(stderr, "%s: Invalid rotation\n", argv[0]);
+			return EX_USAGE;
+		}
+	}else
+		r = 13; /* default to rot13 */
 
-		while((c = GETC(stdin)) != ENDOFFILE)
-			if(isalpha(c)){
-				a = isupper(c) ? alpha_upper : alpha_lower;
-				PUTC(a[c - a[0] + 13], stdout);
-			}else
-				PUTC(c, stdout);
-	}
 
+	while((c = GETC(stdin)) != ENDOFFILE)
+		if(PUTC(caesar(c, r), stdout) == ENDOFFILE)
+			break;
+	
 	return EX_OK;
 }