Dump and recover tokens after preprocessing.

Makefile

@@ -147,7 +147,7 @@ build/asmg.x86: build/asmg.x86.exe build/initrd-asmg.ar
 	cat $^ > $@
 
 build/debugfs.img:
-	echo 'DEBUGFS ' > $@
+	echo -n 'DEBUGFS ' > $@
 	dd if=/dev/zero of=$@ bs=1M count=10 oflag=append conv=notrunc
 
 build/boot_asmg.x86: build/bootloader.x86.mbr build/bootloader.x86.stage2 build/asmg.x86 build/diskfs.img build/debugfs.img

asmg/debugfs.g

@@ -80,6 +80,7 @@ fun _debugfsinst_flush_buffer 1 {
   debugfs DEBUGFS_BUF take free ;
   debugfs DEBUGFS_BUF take_addr 512 1 calloc = ;
   debugfs DEBUGFS_BUF_POS take_addr 0 = ;
+  debugfs DEBUGFS_POS take_addr debugfs DEBUGFS_POS take 1 + = ;
 }
 
 fun debugfsinst_write_char 2 {
@@ -104,6 +105,11 @@ fun debugfsinst_finish_file 1 {
     debugfs _debugfsinst_flush_buffer ;
   }
 
+  # Write an empty sector
+  debugfs '\0' debugfsinst_write_char ;
+  debugfs _debugfsinst_flush_buffer ;
+
+  debugfs DEBUGFS_BUF take free ;
   debugfs DEBUGFS_BUF take_addr 0 = ;
 }
 

asmg/tinycc.g

@@ -22,7 +22,7 @@ fun compile_tinycc 0 {
   # Preprocessing
   $ctx
   @ctx ppctx_init = ;
-  ctx "ONE_SOURCE" "0" ppctx_define ;
+  ctx "ONE_SOURCE" "1" ppctx_define ;
   ctx "USE_SOFTFLOAT" "1" ppctx_define ;
   ctx filename ppctx_set_base_filename ;
   ctx "/disk1/tinycc/softfloat/" ppctx_add_include_path ;

extract_debugfs.py

@@ -0,0 +1,59 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+# This file is part of asmc, a bootstrapping OS with minimal seed
+# Copyright (C) 2018 Giovanni Mascellani <gio@debian.org>
+# https://gitlab.com/giomasce/asmc
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+import sys
+import os
+import struct
+
+def main():
+    assert len(sys.argv) == 2
+    disk_filename = sys.argv[1]
+    with open(disk_filename, 'rb') as fdisk:
+        mbr = fdisk.read(512)
+        assert len(mbr) == 512
+        parts_data = mbr[0x1be:0x1fe]
+        for i in range(4):
+            part_data = parts_data[16*i:16*(i+1)]
+            if part_data[4] == b'\x00':
+                continue
+            start_lba, sectors = struct.unpack('<II', part_data[8:])
+            fdisk.seek(start_lba * 512, os.SEEK_SET)
+            magic = fdisk.read(8)
+            if magic == b'DEBUGFS ':
+                print('Debug partition found!')
+                current_lba = start_lba + 1
+                fdisk.seek(current_lba * 512, os.SEEK_SET)
+                while True:
+                    filename_raw = fdisk.read(512)
+                    current_lba += 1
+                    filename = bytes([b for b in filename_raw if b != 0]).decode('ascii')
+                    if filename == '':
+                        break
+                    with open('debugfs/{}'.format(filename), 'wb') as fout:
+                        while True:
+                            block = fdisk.read(512)
+                            current_lba += 1
+                            if block == b'\x00' * 512:
+                                break
+                            fout.write(bytes([b for b in block if b != 0]))
+                    print(filename)
+
+if __name__ == '__main__':
+    main()