From 1be1abc0afdbeb3086b279b124f8f2b823626ca0 Mon Sep 17 00:00:00 2001
From: Peter Evans <peter@modul8r.com>
Date: Sat, 24 Feb 2018 18:57:00 -0600
Subject: [PATCH] Add printaddr, printstate

---
 include/vm_debug.h | 12 +++++++-----
 src/vm_debug.c     | 28 ++++++++++++++++++++++++----
 tests/vm_debug.c   | 14 ++++++++++++++
 3 files changed, 45 insertions(+), 9 deletions(-)

diff --git a/include/vm_debug.h b/include/vm_debug.h
index 51a54b0..7ad1a42 100644
--- a/include/vm_debug.h
+++ b/include/vm_debug.h
@@ -15,16 +15,16 @@ typedef struct {
     char *name;
     char *abbrev;
 
-    /*
-     * The number of arguments we expect to see
-     */
-    int nargs;
-
     /*
      * The function that will do something with the command's input
      */
     vm_debug_func handler;
 
+    /*
+     * The number of arguments we expect to see
+     */
+    int nargs;
+
     /*
      * What do our arguments look like?
      */
@@ -68,6 +68,8 @@ extern vm_debug_cmd *vm_debug_find_cmd(const char *);
 extern void vm_debug_execute(const char *);
 
 extern DEBUG_CMD(help);
+extern DEBUG_CMD(printaddr);
+extern DEBUG_CMD(printstate);
 extern DEBUG_CMD(resume);
 
 #endif
diff --git a/src/vm_debug.c b/src/vm_debug.c
index eaa37d9..238e3ee 100644
--- a/src/vm_debug.c
+++ b/src/vm_debug.c
@@ -7,14 +7,19 @@
 #include <stdlib.h>
 #include <strings.h>
 
+#include "mos6502.h"
 #include "vm_debug.h"
 #include "vm_di.h"
 #include "vm_reflect.h"
 
 vm_debug_cmd cmdtable[] = {
-    { "help", "h", 0, vm_debug_cmd_help, "",
+    { "help", "h", vm_debug_cmd_help, 0, "",
         "Print out this list of commands", },
-    { "resume", "r", 0, vm_debug_cmd_resume, "",
+    { "printaddr", "pa", vm_debug_cmd_printaddr, 1, "<addr>",
+        "Print the value at memory address <addr>", },
+    { "printstate", "ps", vm_debug_cmd_printstate, 0, "",
+        "Print the machine and CPU state", },
+    { "resume", "r", vm_debug_cmd_resume, 0, "",
         "Resume execution", },
 };
 
@@ -37,8 +42,7 @@ vm_debug_next_arg(char **str)
         break;
     }
 
-    return tok;
-}
+    return tok; }
 
 int
 vm_debug_addr(const char *str)
@@ -161,3 +165,19 @@ DEBUG_CMD(resume)
 {
     vm_reflect_pause(NULL);
 }
+
+DEBUG_CMD(printstate)
+{
+    vm_reflect_cpu_info(NULL);
+    vm_reflect_machine_info(NULL);
+}
+
+DEBUG_CMD(printaddr)
+{
+    // FIXME: This is... too machine-specific; we need to abstract this logic
+    
+    mos6502 *cpu = (mos6502 *)vm_di_get(VM_CPU);
+    FILE *stream = (FILE *)vm_di_get(VM_OUTPUT);
+
+    fprintf(stream, "$%02X\n", mos6502_get(cpu, args->addr1));
+}
diff --git a/tests/vm_debug.c b/tests/vm_debug.c
index 83a7367..d8cfb11 100644
--- a/tests/vm_debug.c
+++ b/tests/vm_debug.c
@@ -94,3 +94,17 @@ Test(vm_debug, cmd_resume)
 
     cr_assert_eq(mach->paused, false);
 }
+
+Test(vm_debug, cmd_printstate)
+{
+    vm_debug_cmd_printstate(&args);
+    cr_assert_neq(strlen(buf), 0);
+}
+
+Test(vm_debug, cmd_printaddr)
+{
+    args.addr1 = 123;
+    mos6502_set(mach->cpu, args.addr1, 127);
+    vm_debug_cmd_printaddr(&args);
+    cr_assert_str_eq(buf, "$7F\n");
+}