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/**
* PhysicsFS; a portable, flexible file i/o abstraction.
*
* This API gives you access to a system file system in ways superior to the
* stdio or system i/o calls. The brief benefits:
*
* - It's portable.
* - It can handle byte ordering on alternative processors.
* - It's safe. No file access is permitted outside the specified dirs.
* - It's flexible. Archives (.ZIP files) can be used transparently as
* directory structures.
*
* This system is largely inspired by Quake 3's PK3 files and the related
* fs_* cvars. If you've ever tinkered with these, then this API will be very
* familiar to you.
*
* With the PhysicsFS, you have a single writing directory and multiple
* "search paths" for reading. You can think of this as a filesystem within a
* filesystem. If (on Windows) you were to set the writing directory to
* "C:\MyGame\MyWritingDirectory", then no PHYSFS calls could touch anything
* above this directory, including the "C:\MyGame" and "C:\" directories.
* This prevents an application's internal scripting language from piddling
* over c:\config.sys, for example. If you'd rather give PHYSFS full access
* to the system's REAL file system, set the writing path to "C:\", but
* that's generally A Bad Thing for several reasons.
*
* Drive letters are hidden in PhysicsFS once you set up your initial paths.
* The search paths create a single, hierarchical directory structure.
* Not only does this lend itself well to general abstraction with archives,
* it also gives better support to operating systems like MacOS and Unix.
* Generally speaking, you shouldn't ever hardcode a drive letter; not only
* does this hurt portability to non-Microsoft OSes, but it limits your win32
* users to a single drive, too. Use the PhysicsFS abstraction functions and
* allow user-defined configuration options, too. When opening a file, you
* specify it like it was on a Unix filesystem: if you want to write to
* "C:\MyGame\MyConfigFiles\game.cfg", then you might set the write path to
* "C:\MyGame" and then open "MyConfigFiles/game.cfg". This gives an
* abstraction across all platforms.
*
* All files opened for writing are opened in relation to the write path,
* which is the root of the writable filesystem. When opening a file for
* reading, PhysicsFS goes through it's internal search path. This is NOT the
* same thing as the PATH environment variable. An application using
* PhysicsFS specifies directories to be searched which may be actual
* directories, or archive files that contain files and subdirectories of
* their own. See the end of these docs for currently supported archive
* formats.
*
* Once a search path is defined, you may open files for reading. If you've
* got the following search path defined (to use a win32 example again):
*
* C:\mygame
* C:\mygame\myuserfiles
* D:\mygamescdromdatafiles
* C:\mygame\installeddatafiles.zip
*
* Then a call to PHYSFS_openread("textfiles/myfile.txt") (note the directory
* separator) will check for C:\mygame\textfiles\myfile.txt, then
* C:\mygame\myuserfiles\textfiles\myfile.txt, then
* D:\mygamescdromdatafiles\textfiles\myfile.txt, then, finally, for
* textfiles\myfile.txt inside of C:\mygame\installeddatafiles.zip. Remember
* that most archive types and platform filesystems store their filenames in
* a case-sensitive manner.
*
* Files opened through PhysicsFS may NOT contain "." or ".." as path
* elements. Not only are these meaningless on MacOS, they are a security
* hole. Also, symbolic links (which can be found in some archive types and
* directly in the filesystem on Unix platforms) are NOT followed until you
* call PHYSFS_permitSymbolicLinks(). That's left to your own discretion, as
* following a symlink can allow for access outside the write and search
* paths. There is no mechanism for creating new symlinks in PhysicsFS.
*
* The write path is not included in the search path unless you specifically
* add it. While you CAN change the write path as many times as you like,
* you should probably set it once and stick to that path.
*
* All files are opened in binary mode; there is no endline conversion for
* textfiles. Other than that, PhysicsFS has some convenience functions for
* platform-independence. There are functions that give you the current
* platform's path separator ("\\" on windows, "/" on Unix, ":" on MacOS),
* which is needed only to set up your search/write paths. There are
* functions to tell you what CD-ROM drives contain accessible discs, and
* functions to recommend good search paths, etc. There are also functions
* to read 16 and 32 bit numbers from files and convert them to the native
* byte order of your processor.
*
* A recommended order for a search path is the write path, then the base path,
* then the cdrom path, then any archives discovered. Quake 3 does something
* like this, but moves the archives to the start of the search path. There
* is a helper function (PHYSFS_setSanePaths()) that does this for you,
* based on a few parameters. Also see the comments on PHYSFS_getBasePath(),
* and PHYSFS_getUserPath() for info on what those are and how they can help
* you determine an optimal searchpath.
*
* While you CAN mix stdio/syscall file access with PHYSFS_* calls in a
* program, doing so is not recommended, and you can not use system
* filehandles with PhysicsFS filehandles and vice versa.
*
* Note that archives need not be named as such: if you have a ZIP file and
* rename it with a .PKG extention, the file will still be recognized as a
* ZIP archive by PhysicsFS; the file's contents are used to determine its
* type.
*
* Currently supported archive types:
* - .ZIP (pkZip/WinZip/Info-ZIP compatible)
*
* Please see the file LICENSE in the source's root directory.
*
* This file written by Ryan C. Gordon.
*/
#ifndef _INCLUDE_PHYSFS_H_
#define _INCLUDE_PHYSFS_H_
#ifdef __cplusplus
extern "C" {
#endif
/* functions... */
/**
* Get the last PhysicsFS error message as a null-terminated string.
* This will be NULL if there's been no error since the last call to this
* function. The pointer returned by this call points to a static buffer
* internal buffer, and this call is not thread safe.
*
* @return READ ONLY string of last error message.
*/
const char *PHYSFS_getLastError(void);
/**
* Get a platform-dependent path separator. This is "\\" on win32, "/" on Unix,
* and ":" on MacOS. It may be more than one character, depending on the
* platform, and your code should take that into account. Note that this is
* only useful for setting up the search/write paths, since access into those
* paths always use '/' to separate directories. This is also handy for
* getting platform-independent access when using stdio calls.
*
* @return READ ONLY null-terminated string of platform's path separator.
*/
const char *PHYSFS_getPathSeparator(void);
/**
* Get an array of paths to available CD-ROM drives. This return value should
* be considered READ ONLY and points to an internal buffer which may change
* with each call to this function. This means that this function is NOT
* thread safe.
*
* The paths returned are platform-dependent ("D:\" on Win32, "/cdrom" or
* whatnot on Unix). Paths are only returned if there is a disc ready and
* accessible in the drive. So if you've got two drives (D: and E:), and only
* E: has a disc in it, then that's all you get. If the user inserts a disc
* in D: and you call this function again, you get both drives. If, on a
* Unix box, the user unmounts a disc and remounts it elsewhere, the next
* call to this function will reflect that change. Fun.
*
* The returned value is an array of strings, with a NULL entry to signify the
* end of the list:
*
* char **i;
*
* // lock thread here, if needed.
*
* for (i = PHYSFS__getCdRomPaths(); *i != NULL; i++)
* printf("cdrom path [%s] is available.\n", *i);
*
* // unlock thread here, if needed.
*
* This call may block while drives spin up. Be forewarned.
*
* @return READ ONLY null-term'd array of READ ONLY null-terminated strings.
*/
const char **PHYSFS_getCdRomPaths(void);
/**
* Helper function.
*
* Get the "base path". This is the directory where the application was run
* from, which is probably the installation directory.
*
* You should probably use the base path in your search path.
*
* @param buffer pointer to buffer to fill with recommended path.
* @param bufsize size of buffer pointed to by (buffer).
* @return a copy of (buffer), for easy use as another function's parameter.
*/
char *PHYSFS_getBasePath(char *buffer, int bufferSize);
/**
* Helper function.
*
* Get the "user path". This is meant to be a suggestion of where a specific
* user of the system can store files. On Unix, this is her home directory.
* On systems with no concept of multiple users (MacOS, win95), this will
* default to the "base path" returned by PHYSFS_getBasePath().
*
* You should probably use the user path as the basis for your write path, and
* also put it near the beginning of your search path.
*
* @param buffer pointer to buffer to fill with recommended path.
* @param bufsize size of buffer pointed to by (buffer).
* @return a copy of (buffer), for easy use as another function's parameter.
*/
char *PHYSFS_getUserPath(char *buffer, int bufferSize);
/**
* Get the current write path. The default write path is NULL.
*
* @param buffer pointer to buffer to fill with recommended path.
* @param bufsize size of buffer pointed to by (buffer).
* @return a copy of (buffer), for easy use as another function's parameter,
* OR NULL IF NO WRITE PATH IS CURRENTLY SET.
*/
char *PHYSFS_getWritePath(char *buffer, int bufferSize);
/**
* Set a new write path. This will override the previous setting. If the
* directory or a parent directory doesn't exist in the physical filesystem,
* PhysicsFS will attempt to create them as needed.
*
* This call will fail (and fail to change the write path) if the current path
* still has files open in it.
*
* @param newPath The new directory to be the root of the write path,
* specified in a platform-dependent manner. Setting to NULL
* disables the write path, so no files can be opened for
* writing via PhysicsFS.
* @return non-zero on success, zero on failure. All attempts to open a file
* for writing via PhysicsFS will fail until this call succeeds.
* Specifics of the error can be gleaned from PHYSFS_getLastError().
*
*/
int PHYSFS_setWritePath(const char *newPath);
/**
* Add a directory or archive to the search path. If this is a duplicate, the
* entry is not added again, even though the function succeeds.
*
* @param newPath directory or archive to add to the path, in
* platform-dependent notation.
* @param appendToPath nonzero to append to search path, zero to prepend.
* @return nonzero if added to path, zero on failure (bogus archive, path
* missing, etc). Specifics of the error can be
* gleaned from PHYSFS_getLastError().
*/
int PHYSFS_addToSearchPath(const char *newPath, int appendToPath);
/**
* Remove a directory or archive to the search path.
*
* This must be a (case-sensitive) match to a dir or archive already in the
* search path, specified in platform-dependent notation.
*
* This call will fail (and fail to remove from the path) if the element still
* has files open in it.
*
* @param oldPath dir/archive to remove.
* @return nonzero on success, zero on failure.
* Specifics of the error can be gleaned from PHYSFS_getLastError().
*/
int PHYSFS_removeFromSearchPath(const char *oldPath);
/**
* Get the current search path. The default search path is an empty list.
*
* This return value should be considered READ ONLY and points to an internal
* buffer which may change with each call to this function. This means that
* this function is NOT thread safe.
*
* The returned value is an array of strings, with a NULL entry to signify the
* end of the list:
*
* char **i;
*
* // lock thread here, if needed.
*
* for (i = PHYSFS_getSearchPath(); *i != NULL; i++)
* printf("[%s] is in the search path.\n", *i);
*
* // unlock thread here, if needed.
*
* @return READ ONLY null-term'd array of READ ONLY null-terminated strings.
*/
const char **PHYSFS_getSearchPath(void);
/**
* Helper function.
*
* Set up sane, default paths. The write path will be set to
* "userpath/.appName", which is created if it doesn't exist.
*
* The above is sufficient to make sure your program's configuration directory
* is separated from other clutter, and platform-independent. The period
* before "mygame" even hides the directory on Unix systems.
*
* The search path will be:
*
* - The Write Path
* - The Write Path/appName
* - The Base Path (PHYSFS_getBasePath())
* - The Base Path/appName
* - All found CD-ROM paths (optionally)
* - All found CD-ROM paths/appName (optionally)
*
* These directories are then searched for files ending with the extension
* (archiveExt), which, if they are valid and supported archives, will also
* be added to the search path. If you specified "PKG" for (archiveExt), and
* there's a file named data.PKG in the base dir, it'll be checked. Archives
* can either be appended or prepended to the search path in alphabetical
* order, regardless of which directories they were found in.
*
* All of this can be accomplished from the application, but this just does it
* all for you.
*
* @param appName Program-specific name of your program, to separate it
* from other programs using PhysicsFS.
*
* @param archiveExt File extention used by your program to specify an
* archive. For example, Quake 3 uses "pk3", even though
* they are just zipfiles. Specify NULL to not dig out
* archives automatically.
*
* @param includeCdRoms Non-zero to include CD-ROMs in the search path, and
* search them for archives. This may cause a
* significant amount of blocking while discs are
* accessed, and if there are no discs in the drive
* (or even not mounted on Unix systems), then they
* may not be made available anyhow. You may want to
* specify zero and handle the disc setup yourself.
*
* @param archivesFirst Non-zero to prepend the archives to the search path.
* Zero to append them.
*/
void PHYSFS_setSanePaths(const char *appName, const char *archiveExt,
int includeCdRoms, int archivesFirst);
/**
* Create a directory. This is specified in platform-independent notation in
* relation to the write path. All missing parent directories are also
* created if they don't exist.
*
* So if you've got the write path set to "C:\mygame\writepath" and call
* PHYSFS_mkdir("downloads/maps") then the directories
* "C:\mygame\writepath\downloads" and "C:\mygame\writepath\downloads\maps"
* will be created if possible.
*
* @param dirname New path to create.
* @return nonzero on success, zero on error. Specifics of the error can be
* gleaned from PHYSFS_getLastError().
*/
int PHYSFS_mkdir(const char *dirName);
/**
* Delete a file or directory. This is specified in platform-independent
* notation in relation to the write path.
*
* A directory must be empty before this call can delete it. If you need to
* nuke a whole directory tree, use PHYSFS_deltree()...with care.
*
* So if you've got the write path set to "C:\mygame\writepath" and call
* PHYSFS_delete("downloads/maps/level1.map") then the file
* "C:\mygame\writepath\downloads\maps\level1.map" is removed from the
* physical filesystem, if it exists and the operating system permits the
* deletion.
*
* @param filename Filename to delete.
* @return nonzero on success, zero on error. Specifics of the error can be
* gleaned from PHYSFS_getLastError().
*/
int PHYSFS_delete(const char *filename);
/**
* Delete a directory tree. This is specified in platform-independent
* notation in relation to the write path.
*
* Be CAREFUL with this function; it will take out EVERYTHING under the
* specified directory with extreme prejudice.
*
* If you specify a filename that is not a directory, PhysicsFS will attempt
* to delete that single file.
*
* So if you've got the write path set to "C:\mygame\writepath" and call
* PHYSFS_deltree("downloads/maps") then the directory
* "C:\mygame\writepath\downloads\maps" and everything in it (including child
* directories) is removed from the physical filesystem, if it exists and the
* operating system permits the deletion.
*
* @param filename root of directory tree to delete.
* @return nonzero on success, zero on error. Specifics of the error can be
* gleaned from PHYSFS_getLastError().
*/
int PHYSFS_deltree(const char *filename);
/**
* Enable symbolic links. Some physical filesystems and archives contain
* files that are just pointers to other files. On the physical filesystem,
* opening such a link will (transparently) open the file that is pointed to.
*
* By default, PhysicsFS will check if a file is really a symlink during open
* calls and fail if it is. Otherwise, the link could take you outside the
* write and search paths, and compromise security.
*
* If you want to take that risk, call this function with a non-zero parameter.
* Note that this is more for sandboxing a program's scripting language, in
* case untrusted scripts try to compromise the system. Generally speaking,
* a user could very well have a legitimate reason to set up a symlink, so
* unless you feel there's a specific danger in allowing them, you should
* permit them.
*
* Symbolic link permission can be enabled or disabled at any time, and is
* disabled by default.
*
* @param allow nonzero to permit symlinks, zero to deny linking.
*/
void PHYSFS_permitSymbolicLinks(int allow);
/**
* Determine if a file exists. Just because it exists does NOT mean that you
* will have access to read or write it.
*
* @param filename a file in platform-independent notation.
* @param inWritePath nonzero to check write path, zero to check search path.
* @return nonzero if exists, zero otherwise.
*/
int PHYSFS_exists(const char *filename, int inWritePath);
/**
* Figure out where in the search path a file resides. The file is specified
* in platform-independent notation. The returned filename will be the
* element of the search path where the file was found, which may be a
* directory, or an archive. Even if there are multiple matches in different
* parts of the search path, only the first one found is used, just like
* when opening a file.
*
* So, if you look for "maps/level1.map", and C:\mygame is in your search
* path and C:\mygame\maps\level1.map exists, then buffer will be filled in
* with "C:\mygame\maps\level1.map" and the function returns nonzero.
*
* @param buffer pointer to buffer to fill with path.
* @param bufsize size of buffer pointed to by (buffer).
* @param filename file to look for.
* @return nonzero if file was found, zero otherwise. If found, (buffer)
* will be filled in.
*/
int PHYSFS_getRealPath(const char *filename, char *buffer, int bufSize);
/**
* Open a file for writing, in platform-independent notation and in relation
* to the write path as the root of the writable filesystem. The specified
* file is created if it doesn't exist. If it does exist, it is truncated to
* zero bytes, and the writing offset is set to the start.
*
* @param filename File to open.
* @return A valid PhysicsFS filehandle on success, NULL on error. Specifics
* of the error can be gleaned from PHYSFS_getLastError().
*/
void *PHYSFS_openWrite(const char *filename);
/**
* Open a file for writing, in platform-independent notation and in relation
* to the write path as the root of the writable filesystem. The specified
* file is created if it doesn't exist. If it does exist, the writing offset
* is set to the end of the file, so the first write will be the byte after
* the end.
*
* @param filename File to open.
* @return A valid PhysicsFS filehandle on success, NULL on error. Specifics
* of the error can be gleaned from PHYSFS_getLastError().
*/
void *PHYSFS_openAppend(const char *filename);
/**
* Open a file for reading, in platform-independent notation. The search path
* is checked one at a time until a matching file is found, in which case an
* abstract filehandle is associated with it, and reading may be done.
* The reading offset is set to the first byte of the file.
*
* @param filename File to open.
* @return A valid PhysicsFS filehandle on success, NULL on error. Specifics
* of the error can be gleaned from PHYSFS_getLastError().
*/
void *PHYSFS_openRead(const char *filename);
/**
* Close a PhysicsFS filehandle. This call is capable of failing if the
* operating system was buffering writes to this file, and (now forced to
* write those changes to physical media) can not store the data for any
* reason. In such a case, the filehandle stays open. A well-written program
* should ALWAYS check the return value from the close call in addition to
* every writing call!
*
* @param handle handle returned from PHYSFS_open*().
* @return nonzero on success, zero on error. Specifics of the error can be
* gleaned from PHYSFS_getLastError().
*/
int PHYSFS_close(void *handle);
/**
* Read data from a PhysicsFS filehandle. The file must be opened for reading.
*
* @param handle handle returned from PHYSFS_openRead().
* @param buffer buffer to store read data into.
* @param objSize size in bytes of objects being read from (handle).
* @param objCount number of (objSize) objects to read from (handle).
* @return number of objects read. PHYSFS_getLastError() can shed light on
* the reason this might be < (objCount).
*/
int PHYSFS_read(void *handle, void *buffer, int objSize, int objCount);
/**
* Write data to a PhysicsFS filehandle. The file must be opened for writing.
*
* @param handle retval from PHYSFS_openWrite() or PHYSFS_openAppend().
* @param buffer buffer to store read data into.
* @param objSize size in bytes of objects being read from (handle).
* @param objCount number of (objSize) objects to read from (handle).
* @return number of objects read. PHYSFS_getLastError() can shed light on
* the reason this might be < (objCount).
*/
int PHYSFS_write(void *handle, void *buffer, int objSize, int objCount);
/**
* Determine if the end of file has been reached in a PhysicsFS filehandle.
*
* @param handle handle returned from PHYSFS_openRead().
* @return nonzero if EOF, zero if not.
*/
int PHYSFS_eof(void *handle);
/**
* Determine current position within a PhysicsFS filehandle.
*
* @param handle handle returned from PHYSFS_open*().
* @return offset in bytes from start of file. -1 if error occurred.
* Specifics of the error can be gleaned from PHYSFS_getLastError().
*/
int PHYSFS_tell(void *handle);
/**
* Seek to a new position within a PhysicsFS filehandle. The next read or write
* will occur at that place. Seeking past the beginning or end of the file is
* not allowed.
*
* @param handle handle returned from PHYSFS_open*().
* @param pos number of bytes from start of file to seek to.
* @return nonzero on success, zero on error. Specifics of the error can be
* gleaned from PHYSFS_getLastError().
*/
int PHYSFS_seek(void *handle, int pos);
/* Byte-order reading. !!! Need types (Int16, Int32, etc) for these...
int PHYSFS_readLE16(void *handle, int *buffer);
int PHYSFS_readLE32(void *handle, int *buffer);
int PHYSFS_readBE16(void *handle, int *buffer);
int PHYSFS_readBE32(void *handle, int *buffer);
int PHYSFS_writeLE16(void *handle, int buffer);
int PHYSFS_writeLE32(void *handle, int buffer);
int PHYSFS_writeBE16(void *handle, int buffer);
int PHYSFS_writeBE32(void *handle, int buffer);
*/
#ifdef __cplusplus
}
#endif
#endif /* !defined _INCLUDE_PHYSFS_H_ */
/* end of physfs.h ... */