--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/fileio.cpp Wed Jan 10 18:12:09 2007 +0000
@@ -0,0 +1,151 @@
+/* $Id$ */
+
+#include "stdafx.h"
+#include "openttd.h"
+#include "fileio.h"
+#include "functions.h"
+#include "string.h"
+#include "macros.h"
+#include "variables.h"
+
+/*************************************************/
+/* FILE IO ROUTINES ******************************/
+/*************************************************/
+
+#define FIO_BUFFER_SIZE 512
+
+typedef struct {
+ byte *buffer, *buffer_end; ///< position pointer in local buffer and last valid byte of buffer
+ uint32 pos; ///< current (system) position in file
+ FILE *cur_fh; ///< current file handle
+ FILE *handles[64]; ///< array of file handles we can have open
+ byte buffer_start[FIO_BUFFER_SIZE]; ///< local buffer when read from file
+} Fio;
+
+static Fio _fio;
+
+// Get current position in file
+uint32 FioGetPos(void)
+{
+ return _fio.pos + (_fio.buffer - _fio.buffer_start) - FIO_BUFFER_SIZE;
+}
+
+void FioSeekTo(uint32 pos, int mode)
+{
+ if (mode == SEEK_CUR) pos += FioGetPos();
+ _fio.buffer = _fio.buffer_end = _fio.buffer_start + FIO_BUFFER_SIZE;
+ _fio.pos = pos;
+ fseek(_fio.cur_fh, _fio.pos, SEEK_SET);
+}
+
+// Seek to a file and a position
+void FioSeekToFile(uint32 pos)
+{
+ FILE *f = _fio.handles[pos >> 24];
+ assert(f != NULL);
+ _fio.cur_fh = f;
+ FioSeekTo(GB(pos, 0, 24), SEEK_SET);
+}
+
+byte FioReadByte(void)
+{
+ if (_fio.buffer == _fio.buffer_end) {
+ _fio.pos += FIO_BUFFER_SIZE;
+ fread(_fio.buffer = _fio.buffer_start, 1, FIO_BUFFER_SIZE, _fio.cur_fh);
+ }
+ return *_fio.buffer++;
+}
+
+void FioSkipBytes(int n)
+{
+ for (;;) {
+ int m = min(_fio.buffer_end - _fio.buffer, n);
+ _fio.buffer += m;
+ n -= m;
+ if (n == 0) break;
+ FioReadByte();
+ n--;
+ }
+}
+
+uint16 FioReadWord(void)
+{
+ byte b = FioReadByte();
+ return (FioReadByte() << 8) | b;
+}
+
+uint32 FioReadDword(void)
+{
+ uint b = FioReadWord();
+ return (FioReadWord() << 16) | b;
+}
+
+void FioReadBlock(void *ptr, uint size)
+{
+ FioSeekTo(FioGetPos(), SEEK_SET);
+ _fio.pos += size;
+ fread(ptr, 1, size, _fio.cur_fh);
+}
+
+static inline void FioCloseFile(int slot)
+{
+ if (_fio.handles[slot] != NULL) {
+ fclose(_fio.handles[slot]);
+ _fio.handles[slot] = NULL;
+ }
+}
+
+void FioCloseAll(void)
+{
+ int i;
+
+ for (i = 0; i != lengthof(_fio.handles); i++)
+ FioCloseFile(i);
+}
+
+bool FioCheckFileExists(const char *filename)
+{
+ FILE *f = FioFOpenFile(filename);
+ if (f == NULL) return false;
+
+ fclose(f);
+ return true;
+}
+
+FILE *FioFOpenFile(const char *filename)
+{
+ FILE *f;
+ char buf[MAX_PATH];
+
+ snprintf(buf, lengthof(buf), "%s%s", _paths.data_dir, filename);
+
+ f = fopen(buf, "rb");
+#if !defined(WIN32)
+ if (f == NULL) {
+ strtolower(buf + strlen(_paths.data_dir) - 1);
+ f = fopen(buf, "rb");
+
+#if defined SECOND_DATA_DIR
+ // tries in the 2nd data directory
+ if (f == NULL) {
+ snprintf(buf, lengthof(buf), "%s%s", _paths.second_data_dir, filename);
+ strtolower(buf + strlen(_paths.second_data_dir) - 1);
+ f = fopen(buf, "rb");
+ }
+#endif
+ }
+#endif
+
+ return f;
+}
+
+void FioOpenFile(int slot, const char *filename)
+{
+ FILE *f = FioFOpenFile(filename);
+
+ if (f == NULL) error("Cannot open file '%s%s'", _paths.data_dir, filename);
+
+ FioCloseFile(slot); // if file was opened before, close it
+ _fio.handles[slot] = f;
+ FioSeekToFile(slot << 24);
+}