IFileSystem

Here you will find all the information you ever wanted to know about the File System in Source: how to open files, how to read files, how to create new directories and how to find a file on the local system.

My Game Directory

This does not deal specifically with the filesystem, but you might find this useful for your project.

//Server
char * pGameDir = new char[1024];
engine->GetGameDir(pGameDir, 1024);

//Client
const char *pGameDir = engine->GetGameDirectory();

Create Directory

To create a directory you need to know two things; the relative path containing the new directory name and Path ID where the path will be created — called a Path ID because it does not appear to be possible to create a directory using anything other than a search path id.

Default Path Ids

DEFAULT_WRITE_PATH
MOD
GAME
GAMEBIN

char * relpath = new char[1024];
Q_snprintf(relpath, 1024, "stuff\\%s", "newdirectory");
filesystem->CreateDirHierarchy( path, "MOD" );

This code will create a newdirectory in your stuff directory, which if does not exist will be created along with newdirectory inside of your MOD directory.

Delete Directory

To remove a directory, first make sure to remove all the files in that directory. Then you can call this code:

#include "direct.h"

char *toRemove = new char[1096];
toRemove[0] = 0;
#ifndef CLIENT_DLL
  char * pGameDir = new char[1024];
  engine->GetGameDir(pGameDir, 1024);
#else
  const char *pGameDir = engine->GetGameDirectory();
#endif
Q_strcat(toRemove, pGameDir);
//concatenate the rest of the directory name here
_rmdir(toRemove);

Copy File

//read in file to copy
FileHandle_t fh = filesystem->Open(copyFromFilename, "rb", "MOD");
int filesize = filesystem->Size(fh);
char *buffer = new char[filesize];
filesystem->Read(buffer, filesize, fh);
filesystem->Close(fh);

//write out copy
fh = filesystem->Open(copyToFilename, "wb", "MOD");
filesystem->Write(buffer, filesize, fh);
filesystem->Close(fh);

File I/O

I/O Modes

`r`	Open a text file for reading
`w`	Create a text file for writing
`a`	Append to a text file
`rb`	Open a binary file for reading
`wb`	Create a binary file for writing
`ab`	Append to a binary file
`r+`	Open a text file for read/write
`w+`	Create a text file for read/write
`a+`	Append to or create a text file for read/write
`rb+`	Open a binary file for read/write
`wb+`	Create a binary file for read/write
`ab+`	Append to or create a binary file for read/write

FileHandle_t fh;
fh = filesystem->Open( "mylog.log", "a", "MOD");

if (fh)
{
    filesystem->FPrintf(fh, "%s", "Logging A Test Line...");  
    filesystem->Close(fh);
}

or

FileHandle_t fh;
fh = filesystem->Open( "mylog.log", "a", "MOD");

if (fh)
{
    char* text = "Logging A Test Line...";
    filesystem->Write(text, Q_strlen(text), fh);  
    filesystem->Close(fh);
}

So in this example we open mylog.log in Append mode. Then we print the line Logging A Test Line... and close the file.

Search Files

To iterate through a list of files in a given Path ID you would do the following.

FileFindHandle_t findHandle;
const char *pFilename = filesystem->FindFirstEx( "*.*", "MOD", &findHandle );
while ( pFilename != NULL )
{
    pFilename = filesystem->FindNext( findHandle );
}
filesystem->FindClose( findHandle );

*.* is the wildcard to match the files against. "MOD" is the Path ID.

The value in pFilename for each filesystem->FindNext is nothing but the file name (i.e. for maps/d1_trainstation_01.bsp, pFilename would be d1_trainstation_01)

Mount Steam Application Content

The following code segment should be added to both CHLClient::Init in src\cl_dll\cdll_client_int.cpp and CServerGameDLL::DLLInit in src\dlls\GameInterface.cpp after filesystem is initialized.

	filesystem->AddSearchPath("path", "GAME");
	if(filesystem->MountSteamContent(id)==FILESYSTEM_MOUNT_FAILED)
		return false;

path should be retrieved from Game Name Abbreviations

id should be retrieved from Steam Application IDs