ref: 7aa93fbe3f348dc05504ca2d10160b13ddf4cf6a
parent: ae17cc670b46856fb2c7dd556cec3f7125608025
author: Simon Howard <fraggle@gmail.com>
date: Fri May 2 18:52:00 EDT 2008
Add Windows memory mapping backend. Subversion-branch: /trunk/chocolate-doom Subversion-revision: 1137
--- /dev/null
+++ b/src/w_file_win32.c
@@ -1,0 +1,182 @@
+// Emacs style mode select -*- C++ -*-
+//-----------------------------------------------------------------------------
+//
+// Copyright(C) 1993-1996 Id Software, Inc.
+// Copyright(C) 2008 Simon Howard
+//
+// 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 2
+// 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, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+// 02111-1307, USA.
+//
+// DESCRIPTION:
+// WAD I/O functions.
+//
+//-----------------------------------------------------------------------------
+
+#include "config.h"
+
+#ifdef _WIN32
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+
+#include "w_file.h"
+#include "z_zone.h"
+
+typedef struct
+{+ wad_file_t wad;
+ HANDLE handle;
+ HANDLE handle_map;
+} win32_wad_file_t;
+
+extern wad_file_class_t win32_wad_file;
+
+static void MapFile(win32_wad_file_t *wad, char *filename)
+{+ wad->handle_map = CreateFileMapping(wad->handle,
+ NULL,
+ PAGE_WRITECOPY,
+ 0,
+ 0,
+ NULL);
+
+ if (wad->handle_map == NULL)
+ {+ fprintf(stderr, "W_Win32_OpenFile: Unable to CreateFileMapping() "
+ "for %s\n" filename);
+ return;
+ }
+
+ wad->wad.mapped = MapViewOfFile(wad->handle_map, FILE_MAP_READ, 0, 0, 0);
+
+ if (wad->wad.mapped == NULL)
+ {+ fprintf(stderr, "W_Win32_OpenFile: Unable to MapViewOfFile() for %s\n",
+ filename);
+ }
+}
+
+unsigned int GetFileLength(HANDLE handle)
+{+ DWORD result;
+
+ result = SetFilePointer(handle, 0, NULL, FILE_END);
+
+ if (result == INVALID_SET_FILE_POINTER)
+ {+ I_Error("W_Win32_OpenFile: Failed to read file length");+ }
+
+ return result;
+}
+
+static wad_file_t *W_Win32_OpenFile(char *path)
+{+ win32_wad_file_t *result;
+ HANDLE handle;
+ OFSTRUCT fileinfo;
+
+ handle = OpenFile(path, &fileinfo, OF_READ);
+
+ if (handle == (HANDLE) HFILE_ERROR)
+ {+ return NULL;
+ }
+
+ // Create a new win32_wad_file_t to hold the file handle.
+
+ result = Z_Malloc(sizeof(win32_wad_file_t), PU_STATIC, 0);
+ result->wad.file_class = &win32_wad_file;
+ result->wad.length = GetFileLength(handle);
+ result->handle = handle;
+
+ // Try to map the file into memory with mmap:
+
+ MapFile(result, path);
+
+ return &result->wad;
+}
+
+static void W_Win32_CloseFile(wad_file_t *wad)
+{+ win32_wad_file_t *win32_wad;
+
+ win32_wad = (win32_wad_file_t *) wad;
+
+ // If mapped, unmap it.
+
+ if (win32_wad->wad.mapped != NULL)
+ {+ UnmapViewOfFile(win32->wad.mapped);
+ }
+
+ if (win32_wad->handle_map != NULL)
+ {+ CloseHandle(win32_wad->handle_map);
+ }
+
+ // Close the file
+
+ if (win32_wad->handle != NULL)
+ {+ CloseHandle(win32_wad->handle);
+ }
+
+ Z_Free(win32_wad);
+}
+
+// Read data from the specified position in the file into the
+// provided buffer. Returns the number of bytes read.
+
+size_t W_Win32_Read(wad_file_t *wad, unsigned int offset,
+ void *buffer, size_t buffer_len)
+{+ win32_wad_file_t *win32_wad;
+ DWORD bytes_read;
+ DWORD result;
+
+ win32_wad = (win32_wad_file_t *) wad;
+
+ // Jump to the specified position in the file.
+
+ result = SetFilePointer(win32_wad->handle, offset, NULL, FILE_START);
+
+ if (result == INVALID_SET_FILE_POINTER)
+ {+ I_Error("W_Win32_Read: Failed to set file pointer to %i",+ offset);
+ }
+
+ // Read into the buffer.
+
+ if (!ReadFile(win32_wad->handle, buffer, buffer_len, &bytes_read, NULL))
+ {+ I_Error("W_Win32_Read: Error reading from file");+ }
+
+ return bytes_read;
+}
+
+
+wad_file_class_t win32_wad_file =
+{+ W_Win32_OpenFile,
+ W_Win32_CloseFile,
+ W_Win32_Read,
+};
+
+
+#endif /* #ifdef _WIN32 */
+