1 files changed, 294 insertions, 0 deletions

diff --git a/src/FileMgr.cpp b/src/FileMgr.cpp
new file mode 100644
index 00000000..3aad9794
--- /dev/null
+++ b/src/FileMgr.cpp
@@ -0,0 +1,294 @@
+#define _CRT_SECURE_NO_WARNINGS
+#include <fcntl.h>
+#include <direct.h>
+#include "common.h"
+#include "patcher.h"
+#include "FileMgr.h"
+
+/*
+ * Windows FILE is BROKEN for GTA.
+ *
+ * We need to support mapping between LF and CRLF for text files
+ * but we do NOT want to end the file at the first sight of a SUB character.
+ * So here is a simple implementation of a FILE interface that works like GTA expects.
+ */
+
+struct myFILE
+{
+	bool isText;
+	FILE *file;
+};
+
+#define NUMFILES 20
+static myFILE myfiles[NUMFILES];
+
+/* Force file to open as binary but remember if it was text mode */
+static int
+myfopen(const char *filename, const char *mode)
+{
+	int fd;
+	char realmode[10], *p;
+
+	for(fd = 1; fd < NUMFILES; fd++)
+		if(myfiles[fd].file == nil)
+			goto found;
+	return 0;	// no free fd
+found:
+	myfiles[fd].isText = strchr(mode, 'b') == nil;
+	p = realmode;
+	while(*mode)
+		if(*mode != 't' && *mode != 'b')
+			*p++ = *mode++;
+		else
+			mode++;
+	*p++ = 'b';
+	*p = '\0';
+	myfiles[fd].file = fopen(filename, realmode);
+	if(myfiles[fd].file == nil)
+		return 0;
+	return fd;
+}
+
+static void
+myfclose(int fd)
+{
+	assert(fd < NUMFILES);
+	if(myfiles[fd].file){
+		fclose(myfiles[fd].file);
+		myfiles[fd].file = nil;
+	}
+}
+
+static int
+myfgetc(int fd)
+{
+	int c;
+	c = fgetc(myfiles[fd].file);
+	if(myfiles[fd].isText && c == 015){
+		/* translate CRLF to LF */
+		c = fgetc(myfiles[fd].file);
+		if(c == 012)
+			return c;
+		ungetc(c, myfiles[fd].file);
+		return 015;
+	}
+	return c;
+}
+
+static int
+myfputc(int c, int fd)
+{
+	/* translate LF to CRLF */
+	if(myfiles[fd].isText && c == 012)
+		fputc(015, myfiles[fd].file);
+	return fputc(c, myfiles[fd].file);
+}
+
+static char*
+myfgets(char *buf, int len, int fd)
+{
+	int c;
+	char *p;
+
+	p = buf;
+	len--;	// NUL byte
+	while(len--){
+		c = myfgetc(fd);
+		if(c == EOF){
+			if(p == buf)
+				return nil;
+			break;
+		}
+		*p++ = c;
+		if(c == '\n')
+			break;
+	}
+	*p = '\0';
+	return buf;
+}
+
+static int
+myfread(void *buf, size_t elt, size_t n, int fd)
+{
+	if(myfiles[fd].isText){
+		char *p;
+		size_t i;
+		int c;
+
+		n *= elt;
+		p = (char*)buf;
+		for(i = 0; i < n; i++){
+			c = myfgetc(fd);
+			if(c == EOF)
+				break;
+			*p++ = c;
+		}
+		return i / elt;
+	}
+	return fread(buf, elt, n, myfiles[fd].file);
+}
+
+static int
+myfwrite(void *buf, size_t elt, size_t n, int fd)
+{
+	if(myfiles[fd].isText){
+		char *p;
+		size_t i;
+		int c;
+
+		n *= elt;
+		p = (char*)buf;
+		for(i = 0; i < n; i++){
+			c = *p++;
+			myfputc(c, fd);
+			if(feof(myfiles[fd].file))	// is this right?
+				break;
+		}
+		return i / elt;
+	}
+	return fwrite(buf, elt, n, myfiles[fd].file);
+}
+
+static int
+myfseek(int fd, long offset, int whence)
+{
+	return fseek(myfiles[fd].file, offset, whence);
+}
+
+static int
+myfeof(int fd)
+{
+	return feof(myfiles[fd].file);
+}
+
+
+char *CFileMgr::ms_rootDirName = (char*)0x5F18F8;
+char *CFileMgr::ms_dirName = (char*)0x713CA8;
+
+void
+CFileMgr::Initialise(void)
+{
+	_getcwd(ms_rootDirName, 128);
+	strcat(ms_rootDirName, "\\");
+}
+
+void
+CFileMgr::ChangeDir(const char *dir)
+{
+	if(*dir == '\\'){
+		strcpy(ms_dirName, ms_rootDirName);
+		dir++;
+	}
+	if(*dir != '\0'){
+		strcat(ms_dirName, dir);
+		// BUG in the game it seems, it's off by one
+		if(dir[strlen(dir)-1] != '\\')
+			strcat(ms_dirName, "\\");
+	}
+	chdir(ms_dirName);
+}
+
+void
+CFileMgr::SetDir(const char *dir)
+{
+	strcpy(ms_dirName, ms_rootDirName);
+	if(*dir != '\0'){
+		strcat(ms_dirName, dir);
+		// BUG in the game it seems, it's off by one
+		if(dir[strlen(dir)-1] != '\\')
+			strcat(ms_dirName, "\\");
+	}
+	chdir(ms_dirName);
+}
+
+void
+CFileMgr::SetDirMyDocuments(void)
+{
+	SetDir("");	// better start at the root if user directory is relative
+	chdir(GetUserDirectory());
+}
+
+int
+CFileMgr::LoadFile(const char *file, uint8 *buf, int unused, const char *mode)
+{
+	int fd;
+	int n, len;
+
+	fd = myfopen(file, mode);
+	if(fd == 0)
+		return 0;
+	len = 0;
+	do{
+		n = myfread(buf + len, 1, 0x4000, fd);
+		if(n < 0)
+			return -1;
+		len += n;
+	}while(n == 0x4000);
+	buf[len] = 0;
+	myfclose(fd);
+	return len;
+}
+
+int
+CFileMgr::OpenFile(const char *file, const char *mode)
+{
+	return myfopen(file, mode);
+}
+
+int
+CFileMgr::OpenFileForWriting(const char *file)
+{
+	return OpenFile(file, "wb");
+}
+
+int
+CFileMgr::Read(int fd, char *buf, int len)
+{
+	return myfread(buf, 1, len, fd);
+}
+
+int
+CFileMgr::Write(int fd, char *buf, int len)
+{
+	return myfwrite(buf, 1, len, fd);
+}
+
+bool
+CFileMgr::Seek(int fd, int offset, int whence)
+{
+	return !!myfseek(fd, offset, whence);
+}
+
+char*
+CFileMgr::ReadLine(int fd, char *buf, int len)
+{
+	return myfgets(buf, len, fd);
+}
+
+void
+CFileMgr::CloseFile(int fd)
+{
+	myfclose(fd);
+}
+
+int
+CFileMgr::GetErrorReadWrite(int fd)
+{
+	return myfeof(fd);
+}
+
+STARTPATCHES
+	InjectHook(0x478F80, CFileMgr::Initialise, PATCH_JUMP);
+	InjectHook(0x478FB0, CFileMgr::ChangeDir, PATCH_JUMP);
+	InjectHook(0x479020, CFileMgr::SetDir, PATCH_JUMP);
+	InjectHook(0x479080, CFileMgr::SetDirMyDocuments, PATCH_JUMP);
+	InjectHook(0x479090, CFileMgr::LoadFile, PATCH_JUMP);
+	InjectHook(0x479100, CFileMgr::OpenFile, PATCH_JUMP);
+	InjectHook(0x479120, CFileMgr::OpenFileForWriting, PATCH_JUMP);
+	InjectHook(0x479140, CFileMgr::Read, PATCH_JUMP);
+	InjectHook(0x479160, CFileMgr::Write, PATCH_JUMP);
+	InjectHook(0x479180, CFileMgr::Seek, PATCH_JUMP);
+	InjectHook(0x4791D0, CFileMgr::ReadLine, PATCH_JUMP);
+	InjectHook(0x479200, CFileMgr::CloseFile, PATCH_JUMP);
+	InjectHook(0x479210, CFileMgr::GetErrorReadWrite, PATCH_JUMP);
+ENDPATCHES