Medical Imaging Interaction Toolkit  2018.4.99-c4b6bb11
Medical Imaging Interaction Toolkit
dirent_win32.h
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1 /*****************************************************************************
2  * dirent.h - dirent API for Microsoft Visual Studio
3  *
4  * Copyright (C) 2006 Toni Ronkko
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining
7  * a copy of this software and associated documentation files (the
8  * ``Software''), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sublicense, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included
15  * in all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS
18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
20  * IN NO EVENT SHALL TONI RONKKO BE LIABLE FOR ANY CLAIM, DAMAGES OR
21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23  * OTHER DEALINGS IN THE SOFTWARE.
24  *
25  * Mar 15, 2011, Toni Ronkko
26  * Defined FILE_ATTRIBUTE_DEVICE for MSVC 6.0.
27  *
28  * Aug 11, 2010, Toni Ronkko
29  * Added d_type and d_namlen fields to dirent structure. The former is
30  * especially useful for determining whether directory entry represents a
31  * file or a directory. For more information, see
32  * http://www.delorie.com/gnu/docs/glibc/libc_270.html
33  *
34  * Aug 11, 2010, Toni Ronkko
35  * Improved conformance to the standards. For example, errno is now set
36  * properly on failure and assert() is never used. Thanks to Peter Brockam
37  * for suggestions.
38  *
39  * Aug 11, 2010, Toni Ronkko
40  * Fixed a bug in rewinddir(): when using relative directory names, change
41  * of working directory no longer causes rewinddir() to fail.
42  *
43  * Dec 15, 2009, John Cunningham
44  * Added rewinddir member function
45  *
46  * Jan 18, 2008, Toni Ronkko
47  * Using FindFirstFileA and WIN32_FIND_DATAA to avoid converting string
48  * between multi-byte and unicode representations. This makes the
49  * code simpler and also allows the code to be compiled under MingW. Thanks
50  * to Azriel Fasten for the suggestion.
51  *
52  * Mar 4, 2007, Toni Ronkko
53  * Bug fix: due to the strncpy_s() function this file only compiled in
54  * Visual Studio 2005. Using the new string functions only when the
55  * compiler version allows.
56  *
57  * Nov 2, 2006, Toni Ronkko
58  * Major update: removed support for Watcom C, MS-DOS and Turbo C to
59  * simplify the file, updated the code to compile cleanly on Visual
60  * Studio 2005 with both unicode and multi-byte character strings,
61  * removed rewinddir() as it had a bug.
62  *
63  * Aug 20, 2006, Toni Ronkko
64  * Removed all remarks about MSVC 1.0, which is antiqued now. Simplified
65  * comments by removing SGML tags.
66  *
67  * May 14 2002, Toni Ronkko
68  * Embedded the function definitions directly to the header so that no
69  * source modules need to be included in the Visual Studio project. Removed
70  * all the dependencies to other projects so that this very header can be
71  * used independently.
72  *
73  * May 28 1998, Toni Ronkko
74  * First version.
75  *****************************************************************************/
76 #ifndef DIRENT_H
77 #define DIRENT_H
78 
79 #ifndef WIN32_LEAN_AND_MEAN
80 #define WIN32_LEAN_AND_MEAN
81 #endif
82 #include <windows.h>
83 #include <string.h>
84 #include <stdlib.h>
85 #include <sys/types.h>
86 #include <sys/stat.h>
87 #include <errno.h>
88 
89 /* Entries missing from MSVC 6.0 */
90 #if !defined(FILE_ATTRIBUTE_DEVICE)
91 # define FILE_ATTRIBUTE_DEVICE 0x40
92 #endif
93 
94 /* File type and permission flags for stat() */
95 #if defined(_MSC_VER) && !defined(S_IREAD)
96 # define S_IFMT _S_IFMT /* file type mask */
97 # define S_IFDIR _S_IFDIR /* directory */
98 # define S_IFCHR _S_IFCHR /* character device */
99 # define S_IFFIFO _S_IFFIFO /* pipe */
100 # define S_IFREG _S_IFREG /* regular file */
101 # define S_IREAD _S_IREAD /* read permission */
102 # define S_IWRITE _S_IWRITE /* write permission */
103 # define S_IEXEC _S_IEXEC /* execute permission */
104 #endif
105 #define S_IFBLK 0 /* block device */
106 #define S_IFLNK 0 /* link */
107 #define S_IFSOCK 0 /* socket */
108 
109 #if defined(_MSC_VER)
110 # define S_IRUSR S_IREAD /* read, user */
111 # define S_IWUSR S_IWRITE /* write, user */
112 # define S_IXUSR 0 /* execute, user */
113 # define S_IRGRP 0 /* read, group */
114 # define S_IWGRP 0 /* write, group */
115 # define S_IXGRP 0 /* execute, group */
116 # define S_IROTH 0 /* read, others */
117 # define S_IWOTH 0 /* write, others */
118 # define S_IXOTH 0 /* execute, others */
119 #endif
120 
121 /* Indicates that d_type field is available in dirent structure */
122 #define _DIRENT_HAVE_D_TYPE
123 
124 /* File type flags for d_type */
125 #define DT_UNKNOWN 0
126 #define DT_REG S_IFREG
127 #define DT_DIR S_IFDIR
128 #define DT_FIFO S_IFFIFO
129 #define DT_SOCK S_IFSOCK
130 #define DT_CHR S_IFCHR
131 #define DT_BLK S_IFBLK
132 
133 /* Macros for converting between st_mode and d_type */
134 #define IFTODT(mode) ((mode) & S_IFMT)
135 #define DTTOIF(type) (type)
136 
137 /*
138  * File type macros. Note that block devices, sockets and links cannot be
139  * distinguished on Windows and the macros S_ISBLK, S_ISSOCK and S_ISLNK are
140  * only defined for compatibility. These macros should always return false
141  * on Windows.
142  */
143 #define S_ISFIFO(mode) (((mode) & S_IFMT) == S_IFFIFO)
144 #define S_ISDIR(mode) (((mode) & S_IFMT) == S_IFDIR)
145 #define S_ISREG(mode) (((mode) & S_IFMT) == S_IFREG)
146 #define S_ISLNK(mode) (((mode) & S_IFMT) == S_IFLNK)
147 #define S_ISSOCK(mode) (((mode) & S_IFMT) == S_IFSOCK)
148 #define S_ISCHR(mode) (((mode) & S_IFMT) == S_IFCHR)
149 #define S_ISBLK(mode) (((mode) & S_IFMT) == S_IFBLK)
150 
151 #ifdef __cplusplus
152 extern "C" {
153 #endif
154 
155 
156 typedef struct dirent
157 {
158  char d_name[MAX_PATH + 1]; /* File name */
159  size_t d_namlen; /* Length of name without \0 */
160  int d_type; /* File type */
161 } dirent;
162 
163 
164 typedef struct DIR
165 {
166  dirent curentry; /* Current directory entry */
167  WIN32_FIND_DATAA find_data; /* Private file data */
168  int cached; /* True if data is valid */
169  HANDLE search_handle; /* Win32 search handle */
170  char patt[MAX_PATH + 3]; /* Initial directory name */
171 } DIR;
172 
173 
174 /* Forward declarations */
175 static DIR *opendir(const char *dirname);
176 static struct dirent *readdir(DIR *dirp);
177 static int closedir(DIR *dirp);
178 static void rewinddir(DIR* dirp);
179 
180 
181 /* Use the new safe string functions introduced in Visual Studio 2005 */
182 #if defined(_MSC_VER) && _MSC_VER >= 1400
183 # define DIRENT_STRNCPY(dest,src,size) strncpy_s((dest),(size),(src),_TRUNCATE)
184 #else
185 # define DIRENT_STRNCPY(dest,src,size) strncpy((dest),(src),(size))
186 #endif
187 
188 /* Set errno variable */
189 #if defined(_MSC_VER)
190 #define DIRENT_SET_ERRNO(x) _set_errno (x)
191 #else
192 #define DIRENT_SET_ERRNO(x) (errno = (x))
193 #endif
194 
195 
196 /*****************************************************************************
197  * Open directory stream DIRNAME for read and return a pointer to the
198  * internal working area that is used to retrieve individual directory
199  * entries.
200  */
201 static DIR *opendir(const char *dirname)
202 {
203  DIR *dirp;
204 
205  /* ensure that the resulting search pattern will be a valid file name */
206  if (dirname == nullptr) {
207  DIRENT_SET_ERRNO (ENOENT);
208  return nullptr;
209  }
210  if (strlen (dirname) + 3 >= MAX_PATH) {
211  DIRENT_SET_ERRNO (ENAMETOOLONG);
212  return nullptr;
213  }
214 
215  /* construct new DIR structure */
216  dirp = (DIR*) malloc (sizeof (struct DIR));
217  if (dirp != nullptr) {
218  int error;
219 
220  /*
221  * Convert relative directory name to an absolute one. This
222  * allows rewinddir() to function correctly when the current working
223  * directory is changed between opendir() and rewinddir().
224  */
225  if (GetFullPathNameA (dirname, MAX_PATH, dirp->patt, nullptr)) {
226  char *p;
227 
228  /* append the search pattern "\\*\0" to the directory name */
229  p = strchr (dirp->patt, '\0');
230  if (dirp->patt < p && *(p-1) != '\\' && *(p-1) != ':') {
231  *p++ = '\\';
232  }
233  *p++ = '*';
234  *p = '\0';
235 
236  /* open directory stream and retrieve the first entry */
237  dirp->search_handle = FindFirstFileA (dirp->patt, &dirp->find_data);
238  if (dirp->search_handle != INVALID_HANDLE_VALUE) {
239  /* a directory entry is now waiting in memory */
240  dirp->cached = 1;
241  error = 0;
242  } else {
243  /* search pattern is not a directory name? */
244  DIRENT_SET_ERRNO (ENOENT);
245  error = 1;
246  }
247  } else {
248  /* buffer too small */
249  DIRENT_SET_ERRNO (ENOMEM);
250  error = 1;
251  }
252 
253  if (error) {
254  free (dirp);
255  dirp = nullptr;
256  }
257  }
258 
259  return dirp;
260 }
261 
262 
263 /*****************************************************************************
264  * Read a directory entry, and return a pointer to a dirent structure
265  * containing the name of the entry in d_name field. Individual directory
266  * entries returned by this very function include regular files,
267  * sub-directories, pseudo-directories "." and "..", but also volume labels,
268  * hidden files and system files may be returned.
269  */
270 static struct dirent *readdir(DIR *dirp)
271 {
272  DWORD attr;
273  if (dirp == nullptr) {
274  /* directory stream did not open */
275  DIRENT_SET_ERRNO (EBADF);
276  return nullptr;
277  }
278 
279  /* get next directory entry */
280  if (dirp->cached != 0) {
281  /* a valid directory entry already in memory */
282  dirp->cached = 0;
283  } else {
284  /* get the next directory entry from stream */
285  if (dirp->search_handle == INVALID_HANDLE_VALUE) {
286  return nullptr;
287  }
288  if (FindNextFileA (dirp->search_handle, &dirp->find_data) == FALSE) {
289  /* the very last entry has been processed or an error occured */
290  FindClose (dirp->search_handle);
292  return nullptr;
293  }
294  }
295 
296  /* copy as a multibyte character string */
298  dirp->find_data.cFileName,
299  sizeof(dirp->curentry.d_name) );
300  dirp->curentry.d_name[MAX_PATH] = '\0';
301 
302  /* compute the length of name */
303  dirp->curentry.d_namlen = strlen (dirp->curentry.d_name);
304 
305  /* determine file type */
306  attr = dirp->find_data.dwFileAttributes;
307  if ((attr & FILE_ATTRIBUTE_DEVICE) != 0) {
308  dirp->curentry.d_type = DT_CHR;
309  } else if ((attr & FILE_ATTRIBUTE_DIRECTORY) != 0) {
310  dirp->curentry.d_type = DT_DIR;
311  } else {
312  dirp->curentry.d_type = DT_REG;
313  }
314  return &dirp->curentry;
315 }
316 
317 
318 /*****************************************************************************
319  * Close directory stream opened by opendir() function. Close of the
320  * directory stream invalidates the DIR structure as well as any previously
321  * read directory entry.
322  */
323 static int closedir(DIR *dirp)
324 {
325  if (dirp == nullptr) {
326  /* invalid directory stream */
327  DIRENT_SET_ERRNO (EBADF);
328  return -1;
329  }
330 
331  /* release search handle */
332  if (dirp->search_handle != INVALID_HANDLE_VALUE) {
333  FindClose (dirp->search_handle);
335  }
336 
337  /* release directory structure */
338  free (dirp);
339  return 0;
340 }
341 
342 
343 /*****************************************************************************
344  * Resets the position of the directory stream to which dirp refers to the
345  * beginning of the directory. It also causes the directory stream to refer
346  * to the current state of the corresponding directory, as a call to opendir()
347  * would have done. If dirp does not refer to a directory stream, the effect
348  * is undefined.
349  */
350 static void rewinddir(DIR* dirp)
351 {
352  if (dirp != nullptr) {
353  /* release search handle */
354  if (dirp->search_handle != INVALID_HANDLE_VALUE) {
355  FindClose (dirp->search_handle);
356  }
357 
358  /* open new search handle and retrieve the first entry */
359  dirp->search_handle = FindFirstFileA (dirp->patt, &dirp->find_data);
360  if (dirp->search_handle != INVALID_HANDLE_VALUE) {
361  /* a directory entry is now waiting in memory */
362  dirp->cached = 1;
363  } else {
364  /* failed to re-open directory: no directory entry in memory */
365  dirp->cached = 0;
366  }
367  }
368 }
369 
370 
371 #ifdef __cplusplus
372 }
373 #endif
374 #endif /*DIRENT_H*/
#define DIRENT_SET_ERRNO(x)
Definition: dirent_win32.h:192
char patt[MAX_PATH+3]
Definition: dirent_win32.h:170
vcl_size_t d_namlen
Definition: dirent_win32.h:159
dirent curentry
Definition: dirent_win32.h:166
#define DT_DIR
Definition: dirent_win32.h:127
static int closedir(DIR *dirp)
Definition: dirent_win32.h:323
int d_type
Definition: dirent_win32.h:160
char d_name[MAX_PATH+1]
Definition: dirent_win32.h:158
#define DT_CHR
Definition: dirent_win32.h:130
int cached
Definition: dirent_win32.h:168
#define FILE_ATTRIBUTE_DEVICE
Definition: dirent_win32.h:91
static void rewinddir(DIR *dirp)
Definition: dirent_win32.h:350
static DIR * opendir(const char *dirname)
Definition: dirent_win32.h:201
static struct dirent * readdir(DIR *dirp)
Definition: dirent_win32.h:270
#define DT_REG
Definition: dirent_win32.h:126
WIN32_FIND_DATAA find_data
Definition: dirent_win32.h:167
#define DIRENT_STRNCPY(dest, src, size)
Definition: dirent_win32.h:185
HANDLE search_handle
Definition: dirent_win32.h:169
struct dirent dirent
struct DIR DIR
#define INVALID_HANDLE_VALUE