IFileSystem

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colorolb 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.

Include

#include "Filesystem.h"

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 (Can include folders, i.e. scripts/weapon.txt) 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];
V_snprintf(relpath, 1024, "stuff\\%s", "newdirectory");
filesystem->CreateDirHierarchy( relpath, "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
V_strcat(toRemove, pGameDir);
//concatenate the rest of the directory name here
_rmdir(toRemove);

Copy File

Warning: Untested

bool CopyFile(const char *from, const char *to)
{
	Assert(from);
	Assert(to);

	CUtlBuffer buf;

	// Read in file to copy
	if(filesystem->ReadFile(from, "MOD", buf))
		return filesystem->WriteFile(to, "MOD", buf); // Write out copy

	return false;
}

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, V_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.

FileHandle_t File; //file wer're reading
File = filesystem->Open( "test/test.txt", "r", "MOD"); //opens a pre-made file in the MOD/test directory called test.txt
int size = filesystem->Size(File); //gets the size of the file
char *Raw = new char[ size + 1 ]; //makes a pointer array 1 bigger to sign
filesystem->Read( Raw, size, File); // reads into the pointer array, the size of the file charecters, from the file
Raw[size] = 0; //signs
Msg(Raw); //outputs to the command line

Toss this little bit of code into a function called by a ConCommand and it can spit out the contents of a 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

- is a negative sign (Subtract) and is required to mount content properly.

See Also