From 513146497f7ddcf560496bfdff06f7adc2e3eb84 Mon Sep 17 00:00:00 2001
From: Martin Mares <mj@ucw.cz>
Date: Wed, 25 Jun 2008 21:11:17 +0200
Subject: [PATCH] Added a simple module for making and parsing hexdumps.

---
 lib/Makefile  |  2 +-
 lib/str-hex.c | 71 +++++++++++++++++++++++++++++++++++++++++++++++++++
 lib/string.h  |  5 ++++
 3 files changed, 77 insertions(+), 1 deletion(-)
 create mode 100644 lib/str-hex.c

diff --git a/lib/Makefile b/lib/Makefile
index 3b3f259f..1196df8f 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -31,7 +31,7 @@ LIBUCW_MODS= \
 	base64 base224 \
 	sync \
 	qache \
-	string str-esc str-split str-match str-imatch \
+	string str-esc str-split str-match str-imatch str-hex \
 	bbuf \
 	getopt
 
diff --git a/lib/str-hex.c b/lib/str-hex.c
new file mode 100644
index 00000000..3dd3e438
--- /dev/null
+++ b/lib/str-hex.c
@@ -0,0 +1,71 @@
+/*
+ *	UCW Library -- Hexdumping and Unhexdumping
+ *
+ *	(c) 2008 Martin Mares <mj@ucw.cz>
+ *
+ *	This software may be freely distributed and used according to the terms
+ *	of the GNU Lesser General Public License.
+ */
+
+#include "lib/lib.h"
+#include "lib/string.h"
+#include "lib/chartype.h"
+
+static uns
+hex_make(uns x)
+{
+  return (x < 10) ? (x + '0') : (x - 10 + 'a');
+}
+
+void
+mem_to_hex(char *dest, const byte *src, uns bytes)
+{
+  while (bytes--)
+    {
+      *dest++ = hex_make(*src >> 4);
+      *dest++ = hex_make(*src & 0x0f);
+      src++;
+    }
+  *dest = 0;
+}
+
+static uns
+hex_parse(uns c)
+{
+  c = Cupcase(c);
+  c -= '0';
+  return (c < 10) ? c : (c - 7);
+}
+
+const char *
+hex_to_mem(byte *dest, const char *src, uns max_bytes)
+{
+  while (max_bytes-- && Cxdigit(src[0]) && Cxdigit(src[1]))
+    {
+      *dest++ = (hex_parse(src[0]) << 4) | hex_parse(src[1]);
+      src += 2;
+    }
+  return src;
+}
+
+#ifdef TEST
+
+#include <stdio.h>
+
+int main(void)
+{
+  byte x[4] = { 0xfe, 0xed, 0xf0, 0x0d };
+  byte y[4];
+  char a[10];
+
+  mem_to_hex(a, x, 4);
+  puts(a);
+  const char *z = hex_to_mem(y, a, 4);
+  if (*z)
+    return 1;
+  printf("%02x%02x%02x%02x\n", y[0], y[1], y[2], y[3]);
+
+  return 0;
+}
+
+#endif
diff --git a/lib/string.h b/lib/string.h
index 50c4dc47..6b0ed593 100644
--- a/lib/string.h
+++ b/lib/string.h
@@ -29,6 +29,11 @@ int str_wordsplit(char *str, char **rec, uns max);
 int str_match_pattern(const char *patt, const char *str);
 int str_match_pattern_nocase(const char *patt, const char *str);
 
+/* str-hex.c */
+
+void mem_to_hex(char *dest, const byte *src, uns bytes);
+const char *hex_to_mem(byte *dest, const char *src, uns max_bytes);
+
 /* md5hex.c */
 
 void md5_to_hex(const byte *s, char *d);
-- 
2.39.2