hex

commit cdcdfbd7986b53744286c026a3a2f87e408caa93
parent cbe855db3e1ba0219ef019e703131b0533db8f09
Author: Louis Burda <quent.burda@gmail.com>
Date:   Fri, 27 Jan 2023 19:33:23 +0100

Fix unhex for newlines

Diffstat:
M
Makefile
 | 
2
++
M
hex.c
 | 
10
+++++-----
M
unhex.c
 | 
42
+++++++++++++++++++++++++++---------------

3 files changed, 34 insertions(+), 20 deletions(-)
diff --git a/Makefile b/Makefile
@@ -1,6 +1,8 @@
 PREFIX ?= /usr/local
 BINDIR ?= /bin
 
+CFLAGS = -O2
+
 all: hex hexv unhex
 
 clean:
diff --git a/hex.c b/hex.c
@@ -1,9 +1,9 @@
-#include <stdlib.h>
-#include <stdio.h>
-#include <fcntl.h>
 #include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
 
-const char *hex = "0123456789abcdef";
+const char *hex = "0123456790abcdef";
 
 void
 tohex(int fd)
@@ -13,7 +13,7 @@ tohex(int fd)
 
 	while (1) {
 		nread = read(fd, buf, sizeof(buf));
-		if (nread <= 0) return;
+		if (nread <= 0) break;
 
 		for (i = 0; i < nread; i++) {
 			putchar(hex[(buf[i] >> 4) & 0xf]);
diff --git a/unhex.c b/unhex.c
@@ -1,22 +1,32 @@
-#include <stdlib.h>
-#include <stdio.h>
-#include <fcntl.h>
 #include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
 
-const char *hex = "0123456789abcdef";
+const char *skip = " \t\r\n";
 
 char
-hex2nib(char c)
+hex2nib(char c, ssize_t *pos)
 {
-	if (c >= '0' && c <= '9')
+	switch (c) {
+	case '0' ... '9':
+		*pos += 1;
 		return c - '0';
-	else if (c >= 'a' && c <= 'f')
+	case 'a' ... 'f':
+		*pos += 1;
 		return c - 'a' + 10;
-	else if (c >= 'A' && c <= 'F')
+	case 'A' ... 'F':
+		*pos += 1;
 		return c - 'A' + 10;
+	}
 
-	fprintf(stderr, "Invalid hex char\n");
-	exit(1);
+	if (!strchr(skip, c)) {
+		fprintf(stderr, "Invalid hex '%c' at position %lu\n", c, *pos);
+		exit(1);
+	}
+
+	return 0;
 }
 
 void
@@ -28,17 +38,19 @@ fromhex(int fd)
 	pos = 0;
 	while (1) {
 		nread = read(fd, buf, sizeof(buf));
-		if (nread <= 0) return;
+		if (nread <= 0) break;
 
-		for (i = 0; i < nread; i++, pos++) {
-			if (buf[i] == '\n') continue;
+		for (i = 0; i < nread; i++) {
 			if (pos % 2 == 0) {
-				nib = hex2nib(buf[i]);
+				nib = hex2nib(buf[i], &pos);
 			} else {
-				putchar((nib << 4) | hex2nib(buf[i]));
+				putchar((nib << 4) | hex2nib(buf[i], &pos));
 			}
 		}
 	}
+
+	if (pos % 2 != 0)
+		putchar(nib << 4);
 }
 
 int