From de901e4d7f2b09c169acde500135587736c824a3 Mon Sep 17 00:00:00 2001 From: "Ryan C. Gordon" Date: Thu, 7 Jun 2001 04:10:40 +0000 Subject: [PATCH] Initial revision --- physfs.h | 597 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 597 insertions(+) create mode 100644 physfs.h diff --git a/physfs.h b/physfs.h new file mode 100644 index 0000000..3bae017 --- /dev/null +++ b/physfs.h @@ -0,0 +1,597 @@ +/** + * 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 ... */ +