1 files changed, 87 insertions, 0 deletions
diff --git a/src/hexdump.c b/src/hexdump.c
new file mode 100644
index 0000000..1d51d99
--- /dev/null
+++ b/src/hexdump.c
@@ -0,0 +1,87 @@
+/*
+ * hexdump.c:
+ *
+ * Copyright (c) 2017 James McKenzie <foss@madingley.org>,
+ * All rights reserved.
+ *
+ */
+
+#include "project.h"
+
+
+static unsigned char
+printable (unsigned char c)
+{
+
+  if (c < ' ')
+    c = '.';
+  if (c > 126)
+    c = '.';
+
+  return c;
+}
+
+
+
+void
+hexdump (char *prefix, void *_d, size_t os, size_t oe)
+{
+  unsigned char *d = (unsigned char *) _d;
+  static unsigned char zero[0x10];
+
+  size_t s, e;
+  size_t i, j;
+  int gap = 0;
+
+  s = os & ~15;
+  e = (oe - 1) | 15;
+  e++;
+
+  for (i = s; i < e; i += 0x10)
+    {
+
+      if (((i > s) && ((i + 0x10) < oe)) && !memcmp (&d[i], zero, 0x10))
+        {
+          gap = 1;
+          continue;
+        }
+      if (gap)
+        {
+          printf ("%s ...\n", prefix);
+          gap = 0;
+        }
+
+
+      printf ("%s %06lx:", prefix, i);
+
+      for (j = i; j < (i + 0x10); ++j)
+        {
+
+          if (j == 8)
+            printf (" ");
+
+          if ((j < os) || (j >= oe))
+            printf ("   ");
+          else
+            printf (" %02x", d[j]);
+        }
+
+      printf ("  ");
+
+      for (j = i; j < (i + 0x10); ++j)
+        {
+
+          if (j == 8)
+            printf (" ");
+
+          if ((j < os) || (j >= oe))
+            printf (" ");
+          else
+            printf ("%c", printable (d[j]));
+        }
+
+
+
+      printf ("\n");
+    }
+}