From 87c7aa92492c33574efc8f878f16025f008c29cd Mon Sep 17 00:00:00 2001
From: Peter Evans <peter@modul8r.com>
Date: Fri, 9 Mar 2018 16:45:20 -0600
Subject: [PATCH] Add hexdump function for vm_segment

---
 include/vm_segment.h |  1 +
 src/vm_segment.c     | 31 +++++++++++++++++++++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/include/vm_segment.h b/include/vm_segment.h
index ecbf0a9..5a255bd 100644
--- a/include/vm_segment.h
+++ b/include/vm_segment.h
@@ -72,6 +72,7 @@ extern vm_8bit vm_segment_get(vm_segment *, size_t);
 extern vm_segment *vm_segment_create(size_t);
 extern void *vm_segment_get_map_machine();
 extern void vm_segment_free(vm_segment *);
+extern void vm_segment_hexdump(vm_segment *, FILE *, size_t, size_t);
 extern void vm_segment_set_map_machine(void *);
 
 #endif
diff --git a/src/vm_segment.c b/src/vm_segment.c
index 01bd0cc..a6ee130 100644
--- a/src/vm_segment.c
+++ b/src/vm_segment.c
@@ -7,6 +7,7 @@
  * etc.
  */
 
+#include <ctype.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -352,3 +353,33 @@ vm_segment_set16(vm_segment *segment, size_t addr, vm_16bit value)
     // code.
     return err;
 }
+
+void
+vm_segment_hexdump(vm_segment *seg, FILE *stream, size_t from, size_t to)
+{
+    char nbuf[51], sbuf[17];
+    int ni = 0, si = 0;
+    int bytes = 0;
+    vm_8bit byte;
+
+    while (from < to) {
+        byte = vm_segment_get(seg, from);
+
+        ni += sprintf(nbuf + ni, "%02X ", byte);
+        si += sprintf(sbuf + si, "%c", isprint(byte) ? byte : '.');
+
+        from++;
+        bytes++;
+
+        if (bytes == 8) {
+            ni += sprintf(nbuf + ni, " ");
+        }
+
+        if (bytes >= 16) {
+            fprintf(stream, "%08zX    %s  [%s]\n", from - bytes, nbuf, sbuf);
+            bytes = 0;
+            ni = 0; 
+            si = 0;
+        }
+    }
+}