From b239cac239e6f79d35ed1dd42d25d4163e94eac1 Mon Sep 17 00:00:00 2001
From: Peter Evans <peter@modul8r.com>
Date: Thu, 1 Mar 2018 19:31:56 -0600
Subject: [PATCH] Add dblock command to disassemble blocks of code

---
 include/vm_debug.h |  1 +
 src/vm_debug.c     | 15 +++++++++++++++
 tests/vm_debug.c   |  9 +++++++++
 3 files changed, 25 insertions(+)

diff --git a/include/vm_debug.h b/include/vm_debug.h
index 3d76bc3..c109133 100644
--- a/include/vm_debug.h
+++ b/include/vm_debug.h
@@ -78,6 +78,7 @@ extern void vm_debug_unbreak(int);
 extern void vm_debug_unbreak_all();
 
 extern DEBUG_CMD(break);
+extern DEBUG_CMD(dblock);
 extern DEBUG_CMD(disasm);
 extern DEBUG_CMD(help);
 extern DEBUG_CMD(jump);
diff --git a/src/vm_debug.c b/src/vm_debug.c
index 37b16b0..bbcf937 100644
--- a/src/vm_debug.c
+++ b/src/vm_debug.c
@@ -11,6 +11,7 @@
 
 #include "apple2.h"
 #include "mos6502.h"
+#include "mos6502.dis.h"
 #include "vm_debug.h"
 #include "vm_di.h"
 #include "vm_reflect.h"
@@ -34,6 +35,8 @@ static bool breakpoints[BREAKPOINTS_MAX];
 vm_debug_cmd cmdtable[] = {
     { "break", "b", vm_debug_cmd_break, 1, "<addr>",
         "Add breakpoint at <addr>", },
+    { "dblock", "db", vm_debug_cmd_dblock, 2, "<from> <to>",
+        "Disassemble a block of code", },
     { "disasm", "d", vm_debug_cmd_disasm, 0, "",
         "Toggle disassembly", },
     { "help", "h", vm_debug_cmd_help, 0, "",
@@ -428,3 +431,15 @@ DEBUG_CMD(disasm)
 
     fprintf(stream, "disassembly %s\n", mach->disasm ? "ON" : "OFF");
 }
+
+DEBUG_CMD(dblock)
+{
+    if (args->addr1 > args->addr2) {
+        return;
+    }
+
+    mos6502 *cpu = (mos6502 *)vm_di_get(VM_CPU);
+    FILE *stream = (FILE *)vm_di_get(VM_OUTPUT);
+
+    mos6502_dis_scan(cpu, stream, args->addr1, args->addr2);
+}
diff --git a/tests/vm_debug.c b/tests/vm_debug.c
index 8f08d81..c39602b 100644
--- a/tests/vm_debug.c
+++ b/tests/vm_debug.c
@@ -278,3 +278,12 @@ Test(vm_debug, cmd_disassemble)
     vm_debug_cmd_disasm(&args);
     cr_assert_eq(mach->disasm, false);
 }
+
+Test(vm_debug, cmd_dblock)
+{
+    mos6502_set(mach->cpu, 0, 0xEA);
+    args.addr1 = 0;
+    args.addr2 = 1;
+    vm_debug_cmd_dblock(&args);
+    cr_assert_neq(strlen(buf), 0);
+}