openjpeg/codec/dirent.h

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/*
* uce-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.
*
*
* May 28 1998, Toni Ronkko <tronkko@messi.uku.fi>
*
* $Id: uce-dirent.h,v 1.7 2002/05/13 10:48:35 tr Exp $
*
* $Log: uce-dirent.h,v $
* Revision 1.7 2002/05/13 10:48:35 tr
* embedded some source code directly to the header so that no source
* modules need to be included in the MS Visual C project using the
* interface, removed all the dependencies to other headers of the `uce'
* library so that the header can be made public
*
* Revision 1.6 2002/04/12 16:22:04 tr
* Unified Compiling Environment (UCE) replaced `std' library
*
* Revision 1.5 2001/07/20 16:33:40 tr
* moved to `std' library and re-named defines accordingly
*
* Revision 1.4 2001/07/10 16:47:18 tronkko
* revised comments
*
* Revision 1.3 2001/01/11 13:16:43 tr
* using ``uce-machine.h'' for finding out defines such as `FREEBSD'
*
* Revision 1.2 2000/10/08 16:00:41 tr
* copy of FreeBSD man page
*
* Revision 1.1 2000/07/10 05:53:16 tr
* Initial revision
*
* Revision 1.2 1998/07/19 18:29:14 tr
* Added error reporting capabilities and some asserts.
*
* Revision 1.1 1998/07/04 16:27:51 tr
* Initial revision
*
*
* MSVC 1.0 scans automatic dependencies incorrectly when your project
* contains this very header. The problem is that MSVC cannot handle
* include directives inside #if..#endif block those are never entered.
* Since this header ought to compile in many different operating systems,
* there had to be several conditional blocks that are compiled only in
* operating systems for what they were designed for. MSVC 1.0 cannot
* handle inclusion of sys/dir.h in a part that is compiled only in Apollo
* operating system. To fix the problem you need to insert DIR.H into
* SYSINCL.DAT located in MSVC\BIN directory and restart visual C++.
* Consult manuals for more informaton about the problem.
*
* Since many UNIX systems have dirent.h we assume to have one also.
* However, if your UNIX system does not have dirent.h you can download one
* for example at: http://ftp.uni-mannheim.de/ftp/GNU/dirent/dirent.tar.gz.
* You can also see if you have one of dirent.h, direct.h, dir.h, ndir.h,
* sys/dir.h and sys/ndir.h somewhere. Try defining HAVE_DIRENT_H,
* HAVE_DIRECT_H, HAVE_DIR_H, HAVE_NDIR_H, HAVE_SYS_DIR_H and
* HAVE_SYS_NDIR_H according to the files found.
*/
#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 <dirent.h>
# 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 <ndir.h>
# define NAMLEN(dp) ((int)((dp)->d_namlen))
#elif defined(HAVE_SYS_NDIR_H)
# include <sys/ndir.h>
# define NAMLEN(dp) ((int)((dp)->d_namlen))
#elif defined(HAVE_DIRECT_H)
# include <direct.h>
# define NAMLEN(dp) ((int)((dp)->d_namlen))
#elif defined(HAVE_DIR_H)
# include <dir.h>
# define NAMLEN(dp) ((int)((dp)->d_namlen))
#elif defined(HAVE_SYS_DIR_H)
# include <sys/types.h>
# include <sys/dir.h>
# 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 <windows.h>
# if !defined(DIRENT_MAXNAMLEN)
# define DIRENT_MAXNAMLEN (MAX_PATH)
# endif
/*** MS-DOS specifics ***/
# elif defined(DIRENT_MSDOS_INTERFACE)
# include <dos.h>
/* Borland defines file length macros in dir.h */
# if defined(__BORLANDC__)
# include <dir.h>
# 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 <dir.h>
# 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
/* supply prototypes for 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
/* 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
static int _initdir (DIR *p);
static const char *_getdirname (const struct dirent *dp);
static void _setdirname (struct DIR *dirp);
/*
* <function name="opendir">
* <intro>open directory stream for reading
* <syntax>DIR *opendir (const char *dirname);
*
* <desc>Open named directory stream 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.
*
* <ret>Returns a pointer to the internal working area or NULL in case the
* directory stream could not be opened. Global `errno' variable will set
* in case of error as follows:
*
* <table>
* [EACESS |Permission denied.
* [EMFILE |Too many open files used by the process.
* [ENFILE |Too many open files in system.
* [ENOENT |Directory does not exist.
* [ENOMEM |Insufficient memory.
* [ENOTDIR |dirname does not refer to directory. This value is not
* reliable on MS-DOS and MS-Windows platforms. Many
* implementations return ENOENT even when the name refers to a
* file.]
* </table>
* </function>
*/
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;
}
/*
* <function name="readdir">
* <intro>read a directory entry
* <syntax>struct dirent *readdir (DIR *dirp);
*
* <desc>Read individual directory entry and return pointer to a structure
* containing the name of the entry. Individual directory entries returned
* 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 are you dealing with. Many dirent implementations already contain
* equivalent information in dirent structure but you cannot depend on
* this.
*
* 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 as 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.Decamps@advalvas.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.
*
* <ret>
* Returns a pointer to a structure containing name of the directory entry
* in `d_name' field or NULL if there was an error. In case of an error the
* global `errno' variable will set as follows:
*
* <table>
* [EBADF |dir parameter refers to an invalid directory stream. This value
* is not set reliably on all implementations.]
* </table>
* </function>
*/
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;
}
/*
* <function name="closedir">
* <intro>close directory stream.
* <syntax>int closedir (DIR *dirp);
*
* <desc>Close directory stream opened by the `opendir' function. Close of
* directory stream invalidates the DIR structure as well as previously read
* dirent entry.
*
* <ret>The function typically returns 0 on success and -1 on failure but
* the function may be declared to return void on same systems. At least
* Borland C/C++ and some UNIX implementations use void as a return type.
* The dirent wrapper tries to define VOID_CLOSEDIR whenever closedir is
* known to return nothing. The very same definition is made by the GNU
* autoconf if you happen to use it.
*
* The global `errno' variable will set to EBADF in case of error.
* </function>
*/
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 and search handles */
if (dirp->dirname != NULL) free (dirp->dirname);
#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;
}
/*
* <function name="rewinddir">
* <intro>rewind directory stream to the beginning
* <syntax>void rewinddir (DIR *dirp);
*
* <desc>Rewind directory stream to the beginning so that the next call of
* readdir() returns the very first directory entry again. However, note
* that next call of readdir() may not return the same directory entry as it
* did in first time. The directory stream may have been affected by newly
* created files.
*
* Almost every dirent implementation ensure that rewinddir will update
* the directory stream to reflect any changes made to the directory entries
* since the previous ``opendir'' or ``rewinddir'' call. Keep an eye on
* this if your program depends on the feature. I know at least one dirent
* implementation where you are required to close and re-open the stream to
* see the changes.
*
* <ret>Returns nothing. If something went wrong while rewinding, you will
* notice it later when you try to retrieve the first directory entry.
*/
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*/