added example patch that shows how to write the VDISK.DLL source

2013-03-11 18:08:42 +00:00 · 2013-03-11 18:08:42 +00:00 · d8c55883a2
parent b6852ba027
commit d8c55883a2
1 changed files with 160 additions and 0 deletions
--- a/bochs/patches/patch.example-vdisk-dll
+++ b/bochs/patches/patch.example-vdisk-dll
@ -0,0 +1,160 @@
+----------------------------------------------------------------------
+Patch name: patch.example-vdisk-dll
+Author:     Volker Ruppert
+Date:       11 Mar 2013
+Status:     Demo
+
+Detailed description:
+  This patch shows how to write the source for the VDISK.DLL required for the
+  disk image mode 'dll'. This demo can be compiled with MSVC nmake and it can
+  be used to access 'flat' type images. Some disk images formats have licenses
+  incompatible with the Bochs one and writing an external DLL could be a way
+  to fix this. The DLL needs to implement these functions:
+
+  int vdisk_open(const char *path, int flags)
+  BOOL vdisk_read(int vunit, LONGLONG blk, void *buf)
+  BOOL vdisk_write(int vunit, LONGLONG blk, const void *buf)
+  void vdisk_close(int vunit)
+  LONGLONG vdisk_get_size(int vunit)
+
+  The function vdisk_open() returns the 'vunit' value to be used in the other
+  functions or -1 on failure. The demo is limited to 8 flat disk images and
+  does not handle the flags value. The 'blk' value is the sector address and
+  the returned size is the sector count.
+
+Apply patch to what version:
+  svn revision 11650
+----------------------------------------------------------------------
+diff -urN ../bochs/misc/vdisk/Makefile ./misc/vdisk/Makefile
+--- ../bochs/misc/vdisk/Makefile	1970-01-01 01:00:00.000000000 +0100
+++ ./misc/vdisk/Makefile	2013-03-11 17:58:03.526467800 +0100
+@@ -0,0 +1,2 @@
+all:
+	cl /nologo /Ox /LD /Tc vdisk.c /link
+diff -urN ../bochs/misc/vdisk/vdisk.c ./misc/vdisk/vdisk.c
+--- ../bochs/misc/vdisk/vdisk.c	1970-01-01 01:00:00.000000000 +0100
+++ ./misc/vdisk/vdisk.c	2013-03-09 12:12:19.687570500 +0100
+@@ -0,0 +1,123 @@
+//  Copyright (C) 2013  Volker Ruppert
+//
+//  This library is free software; you can redistribute it and/or
+//  modify it under the terms of the GNU Lesser General Public
+//  License as published by the Free Software Foundation; either
+//  version 2 of the License, or (at your option) any later version.
+//
+//  This library 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
+//  Lesser General Public License for more details.
+//
+//  You should have received a copy of the GNU Lesser General Public
+//  License along with this library; if not, write to the Free Software
+//  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+
+// VDISK.DLL (demo for disk image mode 'dll')
+
+#include <windows.h>
+
+#define VUNIT_MAX 8
+
+HANDLE hFile[VUNIT_MAX];
+BOOL vunit_open[VUNIT_MAX];
+UINT vunit_count;
+
+__declspec(dllexport) BOOL WINAPI DllMain(HINSTANCE hDLLInst, DWORD fdwReason, LPVOID lpvReserved)
+{
+  int i;
+
+  switch (fdwReason) {
+    case DLL_PROCESS_ATTACH:
+      vunit_count = 0;
+      for (i = 0; i < VUNIT_MAX; i++)
+        vunit_open[i] = FALSE;
+      break;
+    case DLL_PROCESS_DETACH:
+      break;
+    case DLL_THREAD_ATTACH:
+      break;
+    case DLL_THREAD_DETACH:
+      break;
+  }
+  return TRUE;
+}
+
+__declspec(dllexport) int vdisk_open(const char *path, int flags)
+{
+  if (vunit_count == VUNIT_MAX)
+    return -1;
+
+  hFile[vunit_count] = CreateFile(path, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ, NULL,
+                                  OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
+  if (hFile[vunit_count] != INVALID_HANDLE_VALUE) {
+    vunit_open[vunit_count] = TRUE;
+    return vunit_count++;
+  } else {
+    return -1;
+  }
+}
+
+__declspec(dllexport) BOOL vdisk_read(int vunit, LONGLONG blk, void *buf)
+{
+  LONG offlo, offhi;
+  DWORD len2;
+
+  if ((vunit < 0) || (vunit >= VUNIT_MAX))
+    return FALSE;
+
+  if (vunit_open[vunit]) {
+    offlo = (LONG)(blk << 9);
+    offhi = (LONG)(blk >> 23);
+    if (SetFilePointer(hFile[vunit], offlo, &offhi, FILE_BEGIN) == INVALID_SET_FILE_POINTER) {
+      return FALSE;
+    }
+    return ReadFile(hFile[vunit], buf, 512, &len2, NULL);
+  }
+  return FALSE;
+}
+
+__declspec(dllexport) BOOL vdisk_write(int vunit, LONGLONG blk, const void *buf)
+{
+  LONG offlo, offhi;
+  DWORD len2;
+
+  if ((vunit < 0) || (vunit >= VUNIT_MAX))
+    return FALSE;
+
+  if (vunit_open[vunit]) {
+    offlo = (LONG)(blk << 9);
+    offhi = (LONG)(blk >> 23);
+    if (SetFilePointer(hFile[vunit], offlo, &offhi, FILE_BEGIN) == INVALID_SET_FILE_POINTER) {
+      return FALSE;
+    }
+    return WriteFile(hFile[vunit], buf, 512, &len2, NULL);
+  }
+  return FALSE;
+}
+
+__declspec(dllexport) void vdisk_close(int vunit)
+{
+  if ((vunit < 0) || (vunit >= VUNIT_MAX))
+    return;
+
+  if (vunit_open[vunit]) {
+    CloseHandle(hFile[vunit]);
+    vunit_open[vunit] = FALSE;
+  }
+}
+
+__declspec(dllexport) LONGLONG vdisk_get_size(int vunit)
+{
+  LARGE_INTEGER fSize;
+
+  if ((vunit < 0) || (vunit >= VUNIT_MAX))
+    return 0;
+
+  if (vunit_open[vunit]) {
+    GetFileSizeEx(hFile[vunit], &fSize);
+    return (LONGLONG)(fSize.QuadPart >> 9);
+  }
+  return 0;
+}