2 Unix SMB/CIFS implementation.
4 Copyright (C) Andrew Tridgell 2001
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 stdio is very convenient, but on some systems the file descriptor
23 in FILE* is 8 bits, so it fails when more than 255 files are open.
25 XFILE replaces stdio. It is less efficient, but at least it works
26 when you have lots of files open
28 The main restriction on XFILE is that it doesn't support seeking,
29 and doesn't support O_RDWR. That keeps the code simple.
34 #define XBUFSIZE BUFSIZ
36 static XFILE _x_stdin
= { 0, NULL
, NULL
, XBUFSIZE
, 0, O_RDONLY
, X_IOFBF
, 0 };
37 static XFILE _x_stdout
= { 1, NULL
, NULL
, XBUFSIZE
, 0, O_WRONLY
, X_IOLBF
, 0 };
38 static XFILE _x_stderr
= { 2, NULL
, NULL
, 0, 0, O_WRONLY
, X_IONBF
, 0 };
40 XFILE
*x_stdin
= &_x_stdin
;
41 XFILE
*x_stdout
= &_x_stdout
;
42 XFILE
*x_stderr
= &_x_stderr
;
45 #define X_FLAG_ERROR 2
46 #define X_FLAG_EINVAL 3
48 /* simulate setvbuf() */
49 int x_setvbuf(XFILE
*f
, char *buf
, int mode
, size_t size
)
52 if (f
->bufused
) return -1;
54 /* on files being read full buffering is the only option */
55 if ((f
->open_flags
& O_ACCMODE
) == O_RDONLY
) {
59 /* destroy any earlier buffer */
67 if (f
->buftype
== X_IONBF
) return 0;
69 /* if buffering then we need some size */
70 if (size
== 0) size
= XBUFSIZE
;
78 /* allocate the buffer */
79 static int x_allocate_buffer(XFILE
*f
)
82 if (f
->bufsize
== 0) return 0;
83 f
->buf
= (char *)SMB_MALLOC(f
->bufsize
);
84 if (!f
->buf
) return 0;
90 /* this looks more like open() than fopen(), but that is quite deliberate.
91 I want programmers to *think* about O_EXCL, O_CREAT etc not just
92 get them magically added
94 XFILE
*x_fopen(const char *fname
, int flags
, mode_t mode
)
98 ret
= SMB_MALLOC_P(XFILE
);
103 memset(ret
, 0, sizeof(XFILE
));
105 if ((flags
& O_ACCMODE
) == O_RDWR
) {
106 /* we don't support RDWR in XFILE - use file
107 descriptors instead */
113 ret
->open_flags
= flags
;
115 ret
->fd
= sys_open(fname
, flags
, mode
);
121 x_setvbuf(ret
, NULL
, X_IOFBF
, XBUFSIZE
);
126 XFILE
*x_fdup(const XFILE
*f
)
131 fd
= dup(x_fileno(f
));
136 ret
= SMB_CALLOC_ARRAY(XFILE
, 1);
143 ret
->open_flags
= f
->open_flags
;
144 x_setvbuf(ret
, NULL
, X_IOFBF
, XBUFSIZE
);
148 /* simulate fclose() */
149 int x_fclose(XFILE
*f
)
153 /* make sure we flush any buffered data */
159 /* make sure data can't leak into a later malloc */
160 memset(f
->buf
, 0, f
->bufsize
);
163 /* check the file descriptor given to the function is NOT one of the static
164 * descriptor of this libreary or we will free unallocated memory
166 if (f
!= x_stdin
&& f
!= x_stdout
&& f
!= x_stderr
) {
172 /* simulate fwrite() */
173 size_t x_fwrite(const void *p
, size_t size
, size_t nmemb
, XFILE
*f
)
178 /* we might be writing unbuffered */
179 if (f
->buftype
== X_IONBF
||
180 (!f
->buf
&& !x_allocate_buffer(f
))) {
181 ret
= write(f
->fd
, p
, size
*nmemb
);
182 if (ret
== -1) return -1;
187 while (total
< size
*nmemb
) {
188 size_t n
= f
->bufsize
- f
->bufused
;
189 n
= MIN(n
, (size
*nmemb
)-total
);
192 /* it's full, flush it */
197 memcpy(f
->buf
+ f
->bufused
, total
+(const char *)p
, n
);
202 /* when line buffered we need to flush at the last linefeed. This can
203 flush a bit more than necessary, but that is harmless */
204 if (f
->buftype
== X_IOLBF
&& f
->bufused
) {
206 for (i
=(size
*nmemb
)-1; i
>=0; i
--) {
207 if (*(i
+(const char *)p
) == '\n') {
217 /* thank goodness for asprintf() */
218 int x_vfprintf(XFILE
*f
, const char *format
, va_list ap
)
226 len
= vasprintf(&p
, format
, ap2
);
227 if (len
<= 0) return len
;
228 ret
= x_fwrite(p
, 1, len
, f
);
233 int x_fprintf(XFILE
*f
, const char *format
, ...)
238 va_start(ap
, format
);
239 ret
= x_vfprintf(f
, format
, ap
);
244 /* at least fileno() is simple! */
245 int x_fileno(const XFILE
*f
)
250 /* simulate fflush() */
251 int x_fflush(XFILE
*f
)
255 if (f
->flags
& X_FLAG_ERROR
) return -1;
257 if ((f
->open_flags
& O_ACCMODE
) != O_WRONLY
) {
262 if (f
->bufused
== 0 || !f
->buf
) return 0;
264 ret
= write(f
->fd
, f
->buf
, f
->bufused
);
265 if (ret
== -1) return -1;
268 if (f
->bufused
> 0) {
269 f
->flags
|= X_FLAG_ERROR
;
270 memmove(f
->buf
, ret
+ (char *)f
->buf
, f
->bufused
);
277 /* simulate setbuffer() */
278 void x_setbuffer(XFILE
*f
, char *buf
, size_t size
)
280 x_setvbuf(f
, buf
, buf
?X_IOFBF
:X_IONBF
, size
);
283 /* simulate setbuf() */
284 void x_setbuf(XFILE
*f
, char *buf
)
286 x_setvbuf(f
, buf
, buf
?X_IOFBF
:X_IONBF
, XBUFSIZE
);
289 /* simulate setlinebuf() */
290 void x_setlinebuf(XFILE
*f
)
292 x_setvbuf(f
, NULL
, X_IOLBF
, 0);
296 /* simulate feof() */
299 if (f
->flags
& X_FLAG_EOF
) return 1;
303 /* simulate ferror() */
304 int x_ferror(XFILE
*f
)
306 if (f
->flags
& X_FLAG_ERROR
) return 1;
310 /* fill the read buffer */
311 static void x_fillbuf(XFILE
*f
)
315 if (f
->bufused
) return;
317 if (!f
->buf
&& !x_allocate_buffer(f
)) return;
319 n
= read(f
->fd
, f
->buf
, f
->bufsize
);
325 /* simulate fgetc() */
326 int x_fgetc(XFILE
*f
)
330 if (f
->flags
& (X_FLAG_EOF
| X_FLAG_ERROR
)) return EOF
;
332 if (f
->bufused
== 0) x_fillbuf(f
);
334 if (f
->bufused
== 0) {
335 f
->flags
|= X_FLAG_EOF
;
339 ret
= *(unsigned char *)(f
->next
);
346 size_t x_fread(void *p
, size_t size
, size_t nmemb
, XFILE
*f
)
349 while (total
< size
*nmemb
) {
352 (total
+(char *)p
)[0] = (char)c
;
358 /* simulate fgets() */
359 char *x_fgets(char *s
, int size
, XFILE
*stream
)
364 int c
= x_fgetc(stream
);
368 if (c
== '\n') break;
370 if (l
==size
|| x_ferror(stream
)) {
377 /* trivial seek, works only for SEEK_SET and SEEK_END if SEEK_CUR is
378 * set then an error is returned */
379 off_t
x_tseek(XFILE
*f
, off_t offset
, int whence
)
381 if (f
->flags
& X_FLAG_ERROR
)
384 /* only SEEK_SET and SEEK_END are supported */
385 /* SEEK_CUR needs internal offset counter */
386 if (whence
!= SEEK_SET
&& whence
!= SEEK_END
) {
387 f
->flags
|= X_FLAG_EINVAL
;
392 /* empty the buffer */
393 switch (f
->open_flags
& O_ACCMODE
) {
398 if (x_fflush(f
) != 0)
406 f
->flags
&= ~X_FLAG_EOF
;
407 return (off_t
)sys_lseek(f
->fd
, offset
, whence
);