Removing xxd.exe binary and add instructions to build

Makefile

@@ -193,6 +193,9 @@ build_single_header:
 		"single_include/AggregateHeaders.cpp" \
 		"single_include/kompute/Kompute.hpp"
 
+win_build_xxd:
+	cd external/bin/ && gcc -o xxd.exe xxd.c -DCYGWIN
+
 format:
 	$(CLANG_FORMAT_BIN) -i -style="{BasedOnStyle: mozilla, IndentWidth: 4}" src/*.cpp src/include/kompute/*.hpp test/*cpp
 

external/bin/xxd.c

@@ -230,7 +230,7 @@ char *pname;
   fprintf(stderr, "    or\n       %s -r [-s [-]offset] [-c cols] [-ps] [infile [outfile]]\n", pname);
   fprintf(stderr, "Options:\n");
   fprintf(stderr, "    -a          toggle autoskip: A single '*' replaces nul-lines. Default off.\n");
-  fprintf(stderr, "    -). Default hex.\n");
+  fprintf(stderr, "    -b          binary digit dump (incompatible with -p,-i,-r). Default hex.\n");
   fprintf(stderr, "    -c cols     format <cols> octets per line. Default 16 (-i: 12, -ps: 30).\n");
   fprintf(stderr, "    -E          show characters in EBCDIC. Default ASCII.\n");
   fprintf(stderr, "    -g          number of octets per group in normal output. Default 2.\n");
@@ -738,7 +738,7 @@ char *argv[];
 	}
       if (hextype == HEX_NORMAL)
 	{
-	  l[c  / octspergrp)] = hexx[(e >> 4) & 0xf];
+	  l[c = (9 + (grplen * p) / octspergrp)] = hexx[(e >> 4) & 0xf];
 	  l[++c]			       = hexx[ e       & 0xf];
 	}
       else /* hextype == HEX_BITS */