From f70f21789b45611f79fd689a012c6115d7d36db1 Mon Sep 17 00:00:00 2001
From: Peter Evans <pevans@activecampaign.com>
Date: Sun, 31 Dec 2017 15:50:59 -0600
Subject: [PATCH] Add flash memory, disassemble options

---
 include/mos6502.h |  1 +
 include/option.h  |  7 +++++++
 src/apple2.c      | 13 +++++++++++++
 src/mos6502.c     |  6 ++++++
 src/option.c      | 22 ++++++++++++++++++++++
 5 files changed, 49 insertions(+)

diff --git a/include/mos6502.h b/include/mos6502.h
index 4289a79..701ce1e 100644
--- a/include/mos6502.h
+++ b/include/mos6502.h
@@ -122,6 +122,7 @@ extern vm_16bit mos6502_pop_stack(mos6502 *);
 extern vm_8bit mos6502_next_byte(mos6502 *);
 extern vm_8bit mos6502_read_byte(mos6502 *);
 extern void mos6502_execute(mos6502 *, vm_8bit);
+extern void mos6502_flash_memory(mos6502 *, vm_segment *);
 extern void mos6502_free(mos6502 *);
 extern void mos6502_modify_status(mos6502 *, vm_8bit, vm_8bit);
 extern void mos6502_push_stack(mos6502 *, vm_16bit);
diff --git a/include/option.h b/include/option.h
index bf315e3..3787d53 100644
--- a/include/option.h
+++ b/include/option.h
@@ -1,13 +1,20 @@
 #ifndef _OPTIONS_H_
 #define _OPTIONS_H_
 
+#include <stdbool.h>
 #include <stdio.h>
 
+enum option_flags {
+    OPTION_FLASH = 1,
+    OPTION_DISASSEMBLE = 2,
+};
+
 /*
  * These are the most possible number of disk inputs we can accept
  */
 #define OPTION_MAX_DISKS 2
 
+extern bool option_flag(int);
 extern FILE *option_get_input(int);
 extern const char *option_get_error();
 extern int option_get_height();
diff --git a/src/apple2.c b/src/apple2.c
index 1b6efa9..3ec7b80 100644
--- a/src/apple2.c
+++ b/src/apple2.c
@@ -7,6 +7,7 @@
 
 #include "apple2.h"
 #include "apple2.draw.h"
+#include "mos6502.dis.h"
 #include "option.h"
 #include "vm_segment.h"
 
@@ -121,6 +122,14 @@ apple2_boot(apple2 *mach)
         }
     }
 
+    if (option_flag(OPTION_FLASH)) {
+        mos6502_flash_memory(mach->cpu, mach->drive1->data);
+    }
+
+    if (option_flag(OPTION_DISASSEMBLE)) {
+        mos6502_dis_scan(mach->cpu, stdout, 0, mach->cpu->memory->size);
+    }
+
     return OK;
 }
 
@@ -195,6 +204,10 @@ apple2_release_key(apple2 *mach)
 void
 apple2_run_loop(apple2 *mach)
 {
+    if (option_flag(OPTION_DISASSEMBLE)) {
+        return;
+    }
+
     while (vm_screen_active(mach->screen)) {
         vm_screen_refresh(mach->screen);
     }
diff --git a/src/mos6502.c b/src/mos6502.c
index 3d286d4..13c3a31 100644
--- a/src/mos6502.c
+++ b/src/mos6502.c
@@ -423,3 +423,9 @@ mos6502_would_jump(int inst_code)
         inst_code == JMP ||
         inst_code == JSR;
 }
+
+void
+mos6502_flash_memory(mos6502 *cpu, vm_segment *segment)
+{
+    vm_segment_copy(cpu->memory, segment, 0, 0, cpu->memory->size - 1);
+}
diff --git a/src/option.c b/src/option.c
index fd1561b..41d11e7 100644
--- a/src/option.c
+++ b/src/option.c
@@ -41,6 +41,8 @@ static char error_buffer[ERRBUF_SIZE] = "";
 static int width = 700;
 static int height = 480;
 
+static int flags = 0;
+
 /*
  * These are all of the options we allow in our long-form options. It's
  * a bit faster to identify them by integer symbols than to do string
@@ -51,14 +53,18 @@ enum options {
     DISK2,
     HELP,
     SIZE,
+    FLASH,
+    DISASSEMBLE,
 };
 
 /*
  * Here are the options we support for program execution.
  */
 static struct option long_options[] = {
+    { "disassemble", 0, NULL, DISASSEMBLE },
     { "disk1", 1, NULL, DISK1 },
     { "disk2", 1, NULL, DISK2 },
+    { "flash", 0, NULL, FLASH },
     { "help", 0, NULL, HELP },
     { "size", 1, NULL, SIZE },
 };
@@ -111,6 +117,10 @@ option_parse(int argc, char **argv)
         opt = getopt_long_only(argc, argv, "", long_options, &index);
 
         switch (opt) {
+            case DISASSEMBLE:
+                flags |= OPTION_DISASSEMBLE;
+                break;
+
             case DISK1:
                 input_source = 1;
                 break;
@@ -119,6 +129,10 @@ option_parse(int argc, char **argv)
                 input_source = 2;
                 break;
 
+            case FLASH:
+                flags |= OPTION_FLASH;
+                break;
+
             case HELP:
                 option_print_help();
                 
@@ -216,8 +230,10 @@ option_print_help()
     fprintf(stderr, "Usage: erc [options...]\n");
     fprintf(stderr, "Options:\n");
     fprintf(stderr, "\
+  --disassemble               Print assembly notation from CPU memory\n\
   --disk1=FILE                Load FILE into disk drive 1\n\
   --disk2=FILE                Load FILE into disk drive 2\n\
+  --flash                     Flash CPU memory with contents of drive 1\n\
   --help                      Print this help message\n\
   --size=WIDTHxHEIGHT         Use WIDTH and HEIGHT for window size\n\
                               (only 700x480 and 875x600 are supported)\n");
@@ -263,3 +279,9 @@ option_get_height()
 {
     return height;
 }
+
+bool
+option_flag(int flag)
+{
+    return flags & flag;
+}