/* * dirent.h - operating system independent dirent implementation * * Copyright (C) 1998-2002 Toni Ronkko * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * ``Software''), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL TONI RONKKO BE LIABLE FOR ANY CLAIM, DAMAGES OR * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. * * * Aug 20, 2006, Toni Ronkko * Removed all remarks about MSVC 1.0, which is antiqued now. Simplified * comments by removing SGML tags. * * May 14 2002, Toni Ronkko * Embedded the function definitions directly to the header so that no source * modules must be included in the MS Visual C project for using the * interface. Removed all the dependencies to other projects so * that this very header can be used independently. * * May 28 1998, Toni Ronkko * First version. */ #ifndef DIRENT_H #define DIRENT_H #define DIRENT_H_INCLUDED /* find out platform */ #if defined(MSDOS) /* MS-DOS */ #elif defined(__MSDOS__) /* Turbo C/Borland */ # define MSDOS #elif defined(__DOS__) /* Watcom */ # define MSDOS #endif #if defined(WIN32) /* MS-Windows */ #elif defined(__NT__) /* Watcom */ # define WIN32 #elif defined(_WIN32) /* Microsoft */ # define WIN32 #elif defined(__WIN32__) /* Borland */ # define WIN32 #endif /* * See what kind of dirent interface we have unless autoconf has already * determinated that. */ #if !defined(HAVE_DIRENT_H) && !defined(HAVE_DIRECT_H) && !defined(HAVE_SYS_DIR_H) && !defined(HAVE_NDIR_H) && !defined(HAVE_SYS_NDIR_H) && !defined(HAVE_DIR_H) # if defined(_MSC_VER) /* Microsoft C/C++ */ /* no dirent.h */ # elif defined(__BORLANDC__) /* Borland C/C++ */ # define HAVE_DIRENT_H # define VOID_CLOSEDIR # elif defined(__TURBOC__) /* Borland Turbo C */ /* no dirent.h */ # elif defined(__WATCOMC__) /* Watcom C/C++ */ # define HAVE_DIRECT_H # elif defined(__apollo) /* Apollo */ # define HAVE_SYS_DIR_H # elif defined(__hpux) /* HP-UX */ # define HAVE_DIRENT_H # elif defined(__alpha) || defined(__alpha__) /* Alpha OSF1 */ # error "not implemented" # elif defined(__sgi) /* Silicon Graphics */ # define HAVE_DIRENT_H # elif defined(sun) || defined(_sun) /* Sun Solaris */ # define HAVE_DIRENT_H # elif defined(__FreeBSD__) /* FreeBSD */ # define HAVE_DIRENT_H # elif defined(__linux__) /* Linux */ # define HAVE_DIRENT_H # elif defined(__GNUC__) /* GNU C/C++ */ # define HAVE_DIRENT_H # else # error "not implemented" # endif #endif /* include proper interface headers */ #if defined(HAVE_DIRENT_H) # include # ifdef FREEBSD # define NAMLEN(dp) ((int)((dp)->d_namlen)) # else # define NAMLEN(dp) ((int)(strlen((dp)->d_name))) # endif #elif defined(HAVE_NDIR_H) # include # define NAMLEN(dp) ((int)((dp)->d_namlen)) #elif defined(HAVE_SYS_NDIR_H) # include # define NAMLEN(dp) ((int)((dp)->d_namlen)) #elif defined(HAVE_DIRECT_H) # include # define NAMLEN(dp) ((int)((dp)->d_namlen)) #elif defined(HAVE_DIR_H) # include # define NAMLEN(dp) ((int)((dp)->d_namlen)) #elif defined(HAVE_SYS_DIR_H) # include # include # ifndef dirent # define dirent direct # endif # define NAMLEN(dp) ((int)((dp)->d_namlen)) #elif defined(MSDOS) || defined(WIN32) /* figure out type of underlaying directory interface to be used */ # if defined(WIN32) # define DIRENT_WIN32_INTERFACE # elif defined(MSDOS) # define DIRENT_MSDOS_INTERFACE # else # error "missing native dirent interface" # endif /*** WIN32 specifics ***/ # if defined(DIRENT_WIN32_INTERFACE) # include # if !defined(DIRENT_MAXNAMLEN) # define DIRENT_MAXNAMLEN (MAX_PATH) # endif /*** MS-DOS specifics ***/ # elif defined(DIRENT_MSDOS_INTERFACE) # include /* Borland defines file length macros in dir.h */ # if defined(__BORLANDC__) # include # if !defined(DIRENT_MAXNAMLEN) # define DIRENT_MAXNAMLEN ((MAXFILE)+(MAXEXT)) # endif # if !defined(_find_t) # define _find_t find_t # endif /* Turbo C defines ffblk structure in dir.h */ # elif defined(__TURBOC__) # include # if !defined(DIRENT_MAXNAMLEN) # define DIRENT_MAXNAMLEN ((MAXFILE)+(MAXEXT)) # endif # define DIRENT_USE_FFBLK /* MSVC */ # elif defined(_MSC_VER) # if !defined(DIRENT_MAXNAMLEN) # define DIRENT_MAXNAMLEN (12) # endif /* Watcom */ # elif defined(__WATCOMC__) # if !defined(DIRENT_MAXNAMLEN) # if defined(__OS2__) || defined(__NT__) # define DIRENT_MAXNAMLEN (255) # else # define DIRENT_MAXNAMLEN (12) # endif # endif # endif # endif /*** generic MS-DOS and MS-Windows stuff ***/ # if !defined(NAME_MAX) && defined(DIRENT_MAXNAMLEN) # define NAME_MAX DIRENT_MAXNAMLEN # endif # if NAME_MAX < DIRENT_MAXNAMLEN # error "assertion failed: NAME_MAX >= DIRENT_MAXNAMLEN" # endif /* * Substitute for real dirent structure. Note that d_name field is a * true character array although we have it copied in the implementation * dependent data. We could save some memory if we had declared d_name * as a pointer refering the name within implementation dependent data. * We have not done that since some code may rely on sizeof(d_name) to be * something other than four. Besides, directory entries are typically so * small that it takes virtually no time to copy them from place to place. */ typedef struct dirent { char d_name[NAME_MAX + 1]; /*** Operating system specific part ***/ # if defined(DIRENT_WIN32_INTERFACE) /*WIN32*/ WIN32_FIND_DATA data; # elif defined(DIRENT_MSDOS_INTERFACE) /*MSDOS*/ # if defined(DIRENT_USE_FFBLK) struct ffblk data; # else struct _find_t data; # endif # endif } dirent; /* * DIR substitute structure containing directory name. The name is * essential for the operation of rewinndir() function. */ typedef struct DIR { char *dirname; /* directory being scanned */ dirent current; /* current entry */ int dirent_filled; /* is current un-processed? */ /*** Operating system specific part ***/ # if defined(DIRENT_WIN32_INTERFACE) HANDLE search_handle; # elif defined(DIRENT_MSDOS_INTERFACE) # endif } DIR; # ifdef __cplusplus extern "C" { # endif /* prototypes of public dirent functions */ static DIR *opendir (const char *dirname); static struct dirent *readdir (DIR *dirp); static int closedir (DIR *dirp); static void rewinddir (DIR *dirp); /* * Implement dirent interface as static functions so that the user does not * need to change his project in any way to use dirent function. With this * it is sufficient to include this very header from source modules using * dirent functions and the functions will be pulled in automatically. */ #include #include #include #include #include /* use ffblk instead of _find_t if requested */ #if defined(DIRENT_USE_FFBLK) # define _A_ARCH (FA_ARCH) # define _A_HIDDEN (FA_HIDDEN) # define _A_NORMAL (0) # define _A_RDONLY (FA_RDONLY) # define _A_SUBDIR (FA_DIREC) # define _A_SYSTEM (FA_SYSTEM) # define _A_VOLID (FA_LABEL) # define _dos_findnext(dest) findnext(dest) # define _dos_findfirst(name,flags,dest) findfirst(name,dest,flags) #endif /* internal prototypes */ static int _initdir (DIR *p); static const char *_getdirname (const struct dirent *dp); static void _setdirname (struct DIR *dirp); /* * Open directory stream DIRNAME for read and return pointer to the * internal working area that is used for retrieving individual directory * entries. The internal working area has no fields of your interest. */ static DIR * opendir( const char *dirname) { DIR *dirp; assert (dirname != NULL); dirp = (DIR*)malloc (sizeof (struct DIR)); if (dirp != NULL) { char *p; /* allocate room for directory name */ dirp->dirname = (char*) malloc (strlen (dirname) + 1 + strlen ("\\*.*")); if (dirp->dirname == NULL) { /* failed to duplicate directory name. errno set by malloc() */ free (dirp); return NULL; } /* * Copy directory name while appending directory separator and "*.*". * Directory separator is not appended if the name already ends with * drive or directory separator. Directory separator is assumed to be * '/' or '\' and drive separator is assumed to be ':'. */ strcpy (dirp->dirname, dirname); p = strchr (dirp->dirname, '\0'); if (dirp->dirname < p && *(p - 1) != '\\' && *(p - 1) != '/' && *(p - 1) != ':') { strcpy (p++, "\\"); } # ifdef DIRENT_WIN32_INTERFACE strcpy (p, "*"); /*scan files with and without extension in win32*/ # else strcpy (p, "*.*"); /*scan files with and without extension in DOS*/ # endif /* open stream */ if (_initdir (dirp) == 0) { /* initialization failed */ free (dirp->dirname); free (dirp); return NULL; } } return dirp; } /* * Read a directory entry and return pointer to a structure containing the * name of the entry. Individual directory entries returned by this very * function include normal files, sub-directories, pseudo-directories "." * and ".." and also volume labels, hidden files and system files in MS-DOS * and MS-Windows. You might want to use stat(2) function to determinate * which one you are dealing with. * * The dirent structure contains several system dependent fields that * generally have no interest to you. The only interesting one is char * d_name[] that is also portable across different systems. The d_name * field contains the name of the directory entry without leading path. * While d_name is portable across different systems, the actual storage * capacity of d_name varies from system to system and there is no portable * way to find out it at compile time. Different systems define the * capacity of d_name with different macros and some systems do not define * capacity at all (besides actual declaration of the field). If you really * need to find out storage capacity of d_name then you might want to try * NAME_MAX macro. The NAME_MAX is defined in POSIX standard althought * there are many MS-DOS and MS-Windows implementations those do not define * it. There are also systems that declare d_name as "char d_name[1]" and * then allocate suitable amount of memory at run-time. Thanks to Alain * Decamps (Alain dot Decamps atsign advalvas dot be) for pointing it out to * me. * * This all leads to the fact that it is difficult to allocate space * for the directory names when the very same program is being compiled on * number of operating systems. Therefore I suggest that you always * allocate space for directory names dynamically. */ static struct dirent * readdir (DIR *dirp) { assert (dirp != NULL); if (dirp == NULL) { errno = EBADF; return NULL; } #if defined(DIRENT_WIN32_INTERFACE) if (dirp->search_handle == INVALID_HANDLE_VALUE) { /* directory stream was opened/rewound incorrectly or it ended normally */ errno = EBADF; return NULL; } #endif if (dirp->dirent_filled != 0) { /* * Directory entry has already been retrieved and there is no need to * retrieve a new one. Directory entry will be retrieved in advance * when the user calls readdir function for the first time. This is so * because real dirent has separate functions for opening and reading * the stream whereas Win32 and DOS dirents open the stream * automatically when we retrieve the first file. Therefore, we have to * save the first file when opening the stream and later we have to * return the saved entry when the user tries to read the first entry. */ dirp->dirent_filled = 0; } else { /* fill in entry and return that */ #if defined(DIRENT_WIN32_INTERFACE) if (FindNextFile (dirp->search_handle, &dirp->current.data) == FALSE) { /* Last file has been processed or an error occured */ FindClose (dirp->search_handle); dirp->search_handle = INVALID_HANDLE_VALUE; errno = ENOENT; return NULL; } # elif defined(DIRENT_MSDOS_INTERFACE) if (_dos_findnext (&dirp->current.data) != 0) { /* _dos_findnext and findnext will set errno to ENOENT when no * more entries could be retrieved. */ return NULL; } # endif _setdirname (dirp); assert (dirp->dirent_filled == 0); } return &dirp->current; } /* * Close directory stream opened by opendir() function. Close of the * directory stream invalidates the DIR structure as well as any previously * read directory entry. * * Usually, the function returns 0 on success and -1 on failure. However, * on some systems, the function has been declared to return void. If you * want to keep your code portable, it may be better to ignore the return * value altogether. */ static int closedir (DIR *dirp) { int retcode = 0; /* make sure that dirp points to legal structure */ assert (dirp != NULL); if (dirp == NULL) { errno = EBADF; return -1; } /* free directory name */ if (dirp->dirname != NULL) { free (dirp->dirname); } /* release search handle */ #if defined(DIRENT_WIN32_INTERFACE) if (dirp->search_handle != INVALID_HANDLE_VALUE) { if (FindClose (dirp->search_handle) == FALSE) { /* Unknown error */ retcode = -1; errno = EBADF; } } #endif /* clear dirp structure to make sure that it cannot be used anymore*/ memset (dirp, 0, sizeof (*dirp)); # if defined(DIRENT_WIN32_INTERFACE) dirp->search_handle = INVALID_HANDLE_VALUE; # endif free (dirp); return retcode; } /* * Rewind the directory stream to re-read the directory entries. If new * files or directories have been created since opendir(), then also these * new files will be available with readdir(). * * Almost every dirent implementation ensures that rewinddir() updates its * internal caches to reflect the current directory structure on disk. * However, if you really depend on this feature, it may be better to close * and re-open the directory stream. I recall one particual dirent * interface, where rewinddir() did not update its internal cache. * * BUGS: If the current working directory is changed between opendir() and * rewinddir(), then the rewound directory stream may refer a non-existent * directory, or at worst case, to another directory. */ static void rewinddir (DIR *dirp) { /* make sure that dirp is legal */ assert (dirp != NULL); if (dirp == NULL) { errno = EBADF; return; } assert (dirp->dirname != NULL); /* close previous stream */ #if defined(DIRENT_WIN32_INTERFACE) if (dirp->search_handle != INVALID_HANDLE_VALUE) { if (FindClose (dirp->search_handle) == FALSE) { /* Unknown error */ errno = EBADF; } } #endif /* re-open previous stream */ if (_initdir (dirp) == 0) { /* initialization failed but we cannot deal with error. User will notice * error later when she tries to retrieve first directory enty. */ /*EMPTY*/; } } /* * Open native directory stream object and retrieve first file. * Be sure to close previous stream before opening new one. */ static int _initdir (DIR *dirp) { assert (dirp != NULL); assert (dirp->dirname != NULL); dirp->dirent_filled = 0; # if defined(DIRENT_WIN32_INTERFACE) /* Open stream and retrieve first file */ dirp->search_handle = FindFirstFile (dirp->dirname, &dirp->current.data); if (dirp->search_handle == INVALID_HANDLE_VALUE) { /* something went wrong but we don't know what. GetLastError() could * give us more information about the error, but then we should map * the error code into errno. */ errno = ENOENT; return 0; } # elif defined(DIRENT_MSDOS_INTERFACE) if (_dos_findfirst (dirp->dirname, _A_SUBDIR | _A_RDONLY | _A_ARCH | _A_SYSTEM | _A_HIDDEN, &dirp->current.data) != 0) { /* _dos_findfirst and findfirst will set errno to ENOENT when no * more entries could be retrieved. */ return 0; } # endif /* initialize DIR and it's first entry */ _setdirname (dirp); dirp->dirent_filled = 1; return 1; } /* * Return implementation dependent name of the current directory entry. */ static const char * _getdirname (const struct dirent *dp) { #if defined(DIRENT_WIN32_INTERFACE) return dp->data.cFileName; #elif defined(DIRENT_USE_FFBLK) return dp->data.ff_name; #else return dp->data.name; #endif } /* * Copy name of implementation dependent directory entry to the d_name field. */ static void _setdirname (struct DIR *dirp) { /* make sure that d_name is long enough */ assert (strlen (_getdirname (&dirp->current)) <= NAME_MAX); strncpy (dirp->current.d_name, _getdirname (&dirp->current), NAME_MAX); dirp->current.d_name[NAME_MAX] = '\0'; /*char d_name[NAME_MAX+1]*/ } # ifdef __cplusplus } # endif # define NAMLEN(dp) ((int)(strlen((dp)->d_name))) #else # error "missing dirent interface" #endif #endif /*DIRENT_H*/