]>
Commit | Line | Data |
---|---|---|
6de9cd9a DN |
1 | /* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc. |
2 | Contributed by Andy Vaught | |
3 | ||
4 | This file is part of the GNU Fortran 95 runtime library (libgfortran). | |
5 | ||
6 | Libgfortran 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, or (at your option) | |
9 | any later version. | |
10 | ||
57dea9f6 TM |
11 | In addition to the permissions in the GNU General Public License, the |
12 | Free Software Foundation gives you unlimited permission to link the | |
13 | compiled version of this file into combinations with other programs, | |
14 | and to distribute those combinations without any restriction coming | |
15 | from the use of this file. (The General Public License restrictions | |
16 | do apply in other respects; for example, they cover modification of | |
17 | the file, and distribution when not linked into a combine | |
18 | executable.) | |
19 | ||
6de9cd9a DN |
20 | Libgfortran is distributed in the hope that it will be useful, |
21 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
22 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
23 | GNU General Public License for more details. | |
24 | ||
25 | You should have received a copy of the GNU General Public License | |
26 | along with Libgfortran; see the file COPYING. If not, write to | |
27 | the Free Software Foundation, 59 Temple Place - Suite 330, | |
28 | Boston, MA 02111-1307, USA. */ | |
29 | ||
30 | /* Unix stream I/O module */ | |
31 | ||
32 | #include "config.h" | |
33 | #include <stdlib.h> | |
34 | #include <limits.h> | |
35 | ||
36 | #include <unistd.h> | |
47289a4e | 37 | #include <stdio.h> |
6de9cd9a DN |
38 | #include <sys/stat.h> |
39 | #include <fcntl.h> | |
40 | ||
f596fc98 | 41 | #ifdef HAVE_SYS_MMAN_H |
6de9cd9a | 42 | #include <sys/mman.h> |
f596fc98 | 43 | #endif |
6de9cd9a DN |
44 | #include <string.h> |
45 | #include <errno.h> | |
46 | ||
47 | #include "libgfortran.h" | |
48 | #include "io.h" | |
49 | ||
50 | #ifndef PATH_MAX | |
51 | #define PATH_MAX 1024 | |
52 | #endif | |
53 | ||
54 | #ifndef MAP_FAILED | |
55 | #define MAP_FAILED ((void *) -1) | |
56 | #endif | |
57 | ||
f596fc98 AL |
58 | #ifndef PROT_READ |
59 | #define PROT_READ 1 | |
60 | #endif | |
61 | ||
62 | #ifndef PROT_WRITE | |
63 | #define PROT_WRITE 2 | |
64 | #endif | |
65 | ||
41724e6a AL |
66 | /* These flags aren't defined on all targets (mingw32), so provide them |
67 | here. */ | |
68 | #ifndef S_IRGRP | |
69 | #define S_IRGRP 0 | |
70 | #endif | |
71 | ||
72 | #ifndef S_IWGRP | |
73 | #define S_IWGRP 0 | |
74 | #endif | |
75 | ||
76 | #ifndef S_IROTH | |
77 | #define S_IROTH 0 | |
78 | #endif | |
79 | ||
80 | #ifndef S_IWOTH | |
81 | #define S_IWOTH 0 | |
82 | #endif | |
83 | ||
6de9cd9a DN |
84 | /* This implementation of stream I/O is based on the paper: |
85 | * | |
86 | * "Exploiting the advantages of mapped files for stream I/O", | |
87 | * O. Krieger, M. Stumm and R. Umrau, "Proceedings of the 1992 Winter | |
88 | * USENIX conference", p. 27-42. | |
89 | * | |
90 | * It differs in a number of ways from the version described in the | |
91 | * paper. First of all, threads are not an issue during I/O and we | |
92 | * also don't have to worry about having multiple regions, since | |
93 | * fortran's I/O model only allows you to be one place at a time. | |
94 | * | |
95 | * On the other hand, we have to be able to writing at the end of a | |
96 | * stream, read from the start of a stream or read and write blocks of | |
97 | * bytes from an arbitrary position. After opening a file, a pointer | |
98 | * to a stream structure is returned, which is used to handle file | |
99 | * accesses until the file is closed. | |
100 | * | |
101 | * salloc_at_r(stream, len, where)-- Given a stream pointer, return a | |
102 | * pointer to a block of memory that mirror the file at position | |
103 | * 'where' that is 'len' bytes long. The len integer is updated to | |
104 | * reflect how many bytes were actually read. The only reason for a | |
105 | * short read is end of file. The file pointer is updated. The | |
106 | * pointer is valid until the next call to salloc_*. | |
107 | * | |
108 | * salloc_at_w(stream, len, where)-- Given the stream pointer, returns | |
109 | * a pointer to a block of memory that is updated to reflect the state | |
110 | * of the file. The length of the buffer is always equal to that | |
111 | * requested. The buffer must be completely set by the caller. When | |
112 | * data has been written, the sfree() function must be called to | |
113 | * indicate that the caller is done writing data to the buffer. This | |
114 | * may or may not cause a physical write. | |
115 | * | |
116 | * Short forms of these are salloc_r() and salloc_w() which drop the | |
117 | * 'where' parameter and use the current file pointer. */ | |
118 | ||
119 | ||
120 | #define BUFFER_SIZE 8192 | |
121 | ||
122 | typedef struct | |
123 | { | |
124 | stream st; | |
125 | ||
126 | int fd; | |
81f4be3c TS |
127 | gfc_offset buffer_offset; /* File offset of the start of the buffer */ |
128 | gfc_offset physical_offset; /* Current physical file offset */ | |
129 | gfc_offset logical_offset; /* Current logical file offset */ | |
130 | gfc_offset dirty_offset; /* Start of modified bytes in buffer */ | |
bf1df0a0 | 131 | gfc_offset file_length; /* Length of the file, -1 if not seekable. */ |
6de9cd9a DN |
132 | |
133 | char *buffer; | |
134 | int len; /* Physical length of the current buffer */ | |
135 | int active; /* Length of valid bytes in the buffer */ | |
136 | ||
137 | int prot; | |
138 | int ndirty; /* Dirty bytes starting at dirty_offset */ | |
139 | ||
140 | unsigned unbuffered:1, mmaped:1; | |
141 | ||
142 | char small_buffer[BUFFER_SIZE]; | |
143 | ||
144 | } | |
145 | unix_stream; | |
146 | ||
147 | /*move_pos_offset()-- Move the record pointer right or left | |
148 | *relative to current position */ | |
149 | ||
150 | int | |
151 | move_pos_offset (stream* st, int pos_off) | |
152 | { | |
153 | unix_stream * str = (unix_stream*)st; | |
154 | if (pos_off < 0) | |
155 | { | |
156 | str->active += pos_off; | |
157 | if (str->active < 0) | |
158 | str->active = 0; | |
159 | ||
160 | str->logical_offset += pos_off; | |
161 | ||
162 | if (str->dirty_offset+str->ndirty > str->logical_offset) | |
163 | { | |
164 | if (str->ndirty + pos_off > 0) | |
165 | str->ndirty += pos_off ; | |
166 | else | |
167 | { | |
168 | str->dirty_offset += pos_off + pos_off; | |
169 | str->ndirty = 0 ; | |
170 | } | |
171 | } | |
172 | ||
173 | return pos_off ; | |
174 | } | |
175 | return 0 ; | |
176 | } | |
177 | ||
178 | ||
179 | /* fix_fd()-- Given a file descriptor, make sure it is not one of the | |
180 | * standard descriptors, returning a non-standard descriptor. If the | |
181 | * user specifies that system errors should go to standard output, | |
182 | * then closes standard output, we don't want the system errors to a | |
183 | * file that has been given file descriptor 1 or 0. We want to send | |
184 | * the error to the invalid descriptor. */ | |
185 | ||
186 | static int | |
187 | fix_fd (int fd) | |
188 | { | |
189 | int input, output, error; | |
190 | ||
191 | input = output = error = 0; | |
192 | ||
f21edfd6 RH |
193 | /* Unix allocates the lowest descriptors first, so a loop is not |
194 | required, but this order is. */ | |
6de9cd9a DN |
195 | |
196 | if (fd == STDIN_FILENO) | |
197 | { | |
198 | fd = dup (fd); | |
199 | input = 1; | |
200 | } | |
201 | if (fd == STDOUT_FILENO) | |
202 | { | |
203 | fd = dup (fd); | |
204 | output = 1; | |
205 | } | |
206 | if (fd == STDERR_FILENO) | |
207 | { | |
208 | fd = dup (fd); | |
209 | error = 1; | |
210 | } | |
211 | ||
212 | if (input) | |
213 | close (STDIN_FILENO); | |
214 | if (output) | |
215 | close (STDOUT_FILENO); | |
216 | if (error) | |
217 | close (STDERR_FILENO); | |
218 | ||
219 | return fd; | |
220 | } | |
221 | ||
222 | ||
223 | /* write()-- Write a buffer to a descriptor, allowing for short writes */ | |
224 | ||
225 | static int | |
226 | writen (int fd, char *buffer, int len) | |
227 | { | |
228 | int n, n0; | |
229 | ||
230 | n0 = len; | |
231 | ||
232 | while (len > 0) | |
233 | { | |
234 | n = write (fd, buffer, len); | |
235 | if (n < 0) | |
236 | return n; | |
237 | ||
238 | buffer += n; | |
239 | len -= n; | |
240 | } | |
241 | ||
242 | return n0; | |
243 | } | |
244 | ||
245 | ||
246 | #if 0 | |
247 | /* readn()-- Read bytes into a buffer, allowing for short reads. If | |
248 | * fewer than len bytes are returned, it is because we've hit the end | |
249 | * of file. */ | |
250 | ||
251 | static int | |
252 | readn (int fd, char *buffer, int len) | |
253 | { | |
254 | int nread, n; | |
255 | ||
256 | nread = 0; | |
257 | ||
258 | while (len > 0) | |
259 | { | |
260 | n = read (fd, buffer, len); | |
261 | if (n < 0) | |
262 | return n; | |
263 | ||
264 | if (n == 0) | |
265 | return nread; | |
266 | ||
267 | buffer += n; | |
268 | nread += n; | |
269 | len -= n; | |
270 | } | |
271 | ||
272 | return nread; | |
273 | } | |
274 | #endif | |
275 | ||
276 | ||
277 | /* get_oserror()-- Get the most recent operating system error. For | |
278 | * unix, this is errno. */ | |
279 | ||
280 | const char * | |
281 | get_oserror (void) | |
282 | { | |
6de9cd9a DN |
283 | return strerror (errno); |
284 | } | |
285 | ||
286 | ||
287 | /* sys_exit()-- Terminate the program with an exit code */ | |
288 | ||
289 | void | |
290 | sys_exit (int code) | |
291 | { | |
6de9cd9a DN |
292 | exit (code); |
293 | } | |
294 | ||
295 | ||
6de9cd9a DN |
296 | /********************************************************************* |
297 | File descriptor stream functions | |
298 | *********************************************************************/ | |
299 | ||
300 | /* fd_flush()-- Write bytes that need to be written */ | |
301 | ||
302 | static try | |
303 | fd_flush (unix_stream * s) | |
304 | { | |
6de9cd9a DN |
305 | if (s->ndirty == 0) |
306 | return SUCCESS;; | |
307 | ||
308 | if (s->physical_offset != s->dirty_offset && | |
309 | lseek (s->fd, s->dirty_offset, SEEK_SET) < 0) | |
310 | return FAILURE; | |
311 | ||
312 | if (writen (s->fd, s->buffer + (s->dirty_offset - s->buffer_offset), | |
313 | s->ndirty) < 0) | |
314 | return FAILURE; | |
315 | ||
316 | s->physical_offset = s->dirty_offset + s->ndirty; | |
bf1df0a0 BD |
317 | |
318 | /* don't increment file_length if the file is non-seekable */ | |
319 | if (s->file_length != -1 && s->physical_offset > s->file_length) | |
6de9cd9a DN |
320 | s->file_length = s->physical_offset; |
321 | s->ndirty = 0; | |
322 | ||
323 | return SUCCESS; | |
324 | } | |
325 | ||
326 | ||
327 | /* fd_alloc()-- Arrange a buffer such that the salloc() request can be | |
328 | * satisfied. This subroutine gets the buffer ready for whatever is | |
329 | * to come next. */ | |
330 | ||
331 | static void | |
81f4be3c | 332 | fd_alloc (unix_stream * s, gfc_offset where, int *len) |
6de9cd9a DN |
333 | { |
334 | char *new_buffer; | |
335 | int n, read_len; | |
336 | ||
337 | if (*len <= BUFFER_SIZE) | |
338 | { | |
339 | new_buffer = s->small_buffer; | |
340 | read_len = BUFFER_SIZE; | |
341 | } | |
342 | else | |
343 | { | |
344 | new_buffer = get_mem (*len); | |
345 | read_len = *len; | |
346 | } | |
347 | ||
348 | /* Salvage bytes currently within the buffer. This is important for | |
349 | * devices that cannot seek. */ | |
350 | ||
351 | if (s->buffer != NULL && s->buffer_offset <= where && | |
352 | where <= s->buffer_offset + s->active) | |
353 | { | |
354 | ||
355 | n = s->active - (where - s->buffer_offset); | |
356 | memmove (new_buffer, s->buffer + (where - s->buffer_offset), n); | |
357 | ||
358 | s->active = n; | |
359 | } | |
360 | else | |
361 | { /* new buffer starts off empty */ | |
362 | s->active = 0; | |
363 | } | |
364 | ||
365 | s->buffer_offset = where; | |
366 | ||
367 | /* free the old buffer if necessary */ | |
368 | ||
369 | if (s->buffer != NULL && s->buffer != s->small_buffer) | |
370 | free_mem (s->buffer); | |
371 | ||
372 | s->buffer = new_buffer; | |
373 | s->len = read_len; | |
374 | s->mmaped = 0; | |
375 | } | |
376 | ||
377 | ||
378 | /* fd_alloc_r_at()-- Allocate a stream buffer for reading. Either | |
379 | * we've already buffered the data or we need to load it. Returns | |
380 | * NULL on I/O error. */ | |
381 | ||
382 | static char * | |
81f4be3c | 383 | fd_alloc_r_at (unix_stream * s, int *len, gfc_offset where) |
6de9cd9a | 384 | { |
81f4be3c | 385 | gfc_offset m; |
6de9cd9a DN |
386 | int n; |
387 | ||
388 | if (where == -1) | |
389 | where = s->logical_offset; | |
390 | ||
391 | if (s->buffer != NULL && s->buffer_offset <= where && | |
392 | where + *len <= s->buffer_offset + s->active) | |
393 | { | |
394 | ||
395 | /* Return a position within the current buffer */ | |
396 | ||
397 | s->logical_offset = where + *len; | |
398 | return s->buffer + where - s->buffer_offset; | |
399 | } | |
400 | ||
401 | fd_alloc (s, where, len); | |
402 | ||
403 | m = where + s->active; | |
404 | ||
405 | if (s->physical_offset != m && lseek (s->fd, m, SEEK_SET) < 0) | |
406 | return NULL; | |
407 | ||
408 | n = read (s->fd, s->buffer + s->active, s->len - s->active); | |
409 | if (n < 0) | |
410 | return NULL; | |
411 | ||
412 | s->physical_offset = where + n; | |
413 | ||
414 | s->active += n; | |
415 | if (s->active < *len) | |
416 | *len = s->active; /* Bytes actually available */ | |
417 | ||
418 | s->logical_offset = where + *len; | |
419 | ||
420 | return s->buffer; | |
421 | } | |
422 | ||
423 | ||
424 | /* fd_alloc_w_at()-- Allocate a stream buffer for writing. Either | |
425 | * we've already buffered the data or we need to load it. */ | |
426 | ||
427 | static char * | |
81f4be3c | 428 | fd_alloc_w_at (unix_stream * s, int *len, gfc_offset where) |
6de9cd9a | 429 | { |
81f4be3c | 430 | gfc_offset n; |
6de9cd9a DN |
431 | |
432 | if (where == -1) | |
433 | where = s->logical_offset; | |
434 | ||
435 | if (s->buffer == NULL || s->buffer_offset > where || | |
436 | where + *len > s->buffer_offset + s->len) | |
437 | { | |
438 | ||
439 | if (fd_flush (s) == FAILURE) | |
440 | return NULL; | |
441 | fd_alloc (s, where, len); | |
442 | } | |
443 | ||
444 | /* Return a position within the current buffer */ | |
bf1df0a0 BD |
445 | if (s->ndirty == 0 |
446 | || where > s->dirty_offset + s->ndirty | |
447 | || s->dirty_offset > where + *len) | |
448 | { /* Discontiguous blocks, start with a clean buffer. */ | |
449 | /* Flush the buffer. */ | |
450 | if (s->ndirty != 0) | |
451 | fd_flush (s); | |
452 | s->dirty_offset = where; | |
453 | s->ndirty = *len; | |
6de9cd9a DN |
454 | } |
455 | else | |
bf1df0a0 BD |
456 | { |
457 | gfc_offset start; /* Merge with the existing data. */ | |
458 | if (where < s->dirty_offset) | |
459 | start = where; | |
460 | else | |
461 | start = s->dirty_offset; | |
462 | if (where + *len > s->dirty_offset + s->ndirty) | |
463 | s->ndirty = where + *len - start; | |
464 | else | |
465 | s->ndirty = s->dirty_offset + s->ndirty - start; | |
466 | s->dirty_offset = start; | |
6de9cd9a DN |
467 | } |
468 | ||
469 | s->logical_offset = where + *len; | |
470 | ||
78579b60 BD |
471 | if (where + *len > s->file_length) |
472 | s->file_length = where + *len; | |
473 | ||
6de9cd9a DN |
474 | n = s->logical_offset - s->buffer_offset; |
475 | if (n > s->active) | |
476 | s->active = n; | |
477 | ||
478 | return s->buffer + where - s->buffer_offset; | |
479 | } | |
480 | ||
481 | ||
482 | static try | |
483 | fd_sfree (unix_stream * s) | |
484 | { | |
6de9cd9a DN |
485 | if (s->ndirty != 0 && |
486 | (s->buffer != s->small_buffer || options.all_unbuffered || | |
487 | s->unbuffered)) | |
488 | return fd_flush (s); | |
489 | ||
490 | return SUCCESS; | |
491 | } | |
492 | ||
493 | ||
494 | static int | |
81f4be3c | 495 | fd_seek (unix_stream * s, gfc_offset offset) |
6de9cd9a | 496 | { |
6de9cd9a DN |
497 | s->physical_offset = s->logical_offset = offset; |
498 | ||
499 | return (lseek (s->fd, offset, SEEK_SET) < 0) ? FAILURE : SUCCESS; | |
500 | } | |
501 | ||
502 | ||
503 | /* truncate_file()-- Given a unit, truncate the file at the current | |
504 | * position. Sets the physical location to the new end of the file. | |
505 | * Returns nonzero on error. */ | |
506 | ||
507 | static try | |
508 | fd_truncate (unix_stream * s) | |
509 | { | |
bf1df0a0 | 510 | if (lseek (s->fd, s->logical_offset, SEEK_SET) == -1) |
6de9cd9a DN |
511 | return FAILURE; |
512 | ||
bf1df0a0 BD |
513 | /* non-seekable files, like terminals and fifo's fail the lseek. |
514 | the fd is a regular file at this point */ | |
6de9cd9a | 515 | |
bf1df0a0 | 516 | if (ftruncate (s->fd, s->logical_offset)) |
6de9cd9a | 517 | return FAILURE; |
bf1df0a0 BD |
518 | |
519 | s->physical_offset = s->file_length = s->logical_offset; | |
6de9cd9a DN |
520 | |
521 | return SUCCESS; | |
522 | } | |
523 | ||
524 | ||
525 | static try | |
526 | fd_close (unix_stream * s) | |
527 | { | |
6de9cd9a DN |
528 | if (fd_flush (s) == FAILURE) |
529 | return FAILURE; | |
530 | ||
531 | if (s->buffer != NULL && s->buffer != s->small_buffer) | |
532 | free_mem (s->buffer); | |
533 | ||
534 | if (close (s->fd) < 0) | |
535 | return FAILURE; | |
536 | ||
537 | free_mem (s); | |
538 | ||
539 | return SUCCESS; | |
540 | } | |
541 | ||
542 | ||
543 | static void | |
544 | fd_open (unix_stream * s) | |
545 | { | |
6de9cd9a DN |
546 | if (isatty (s->fd)) |
547 | s->unbuffered = 1; | |
548 | ||
549 | s->st.alloc_r_at = (void *) fd_alloc_r_at; | |
550 | s->st.alloc_w_at = (void *) fd_alloc_w_at; | |
551 | s->st.sfree = (void *) fd_sfree; | |
552 | s->st.close = (void *) fd_close; | |
553 | s->st.seek = (void *) fd_seek; | |
554 | s->st.truncate = (void *) fd_truncate; | |
555 | ||
556 | s->buffer = NULL; | |
557 | } | |
558 | ||
559 | ||
560 | /********************************************************************* | |
561 | mmap stream functions | |
562 | ||
563 | Because mmap() is not capable of extending a file, we have to keep | |
564 | track of how long the file is. We also have to be able to detect end | |
565 | of file conditions. If there are multiple writers to the file (which | |
566 | can only happen outside the current program), things will get | |
567 | confused. Then again, things will get confused anyway. | |
568 | ||
569 | *********************************************************************/ | |
570 | ||
571 | #if HAVE_MMAP | |
572 | ||
573 | static int page_size, page_mask; | |
574 | ||
575 | /* mmap_flush()-- Deletes a memory mapping if something is mapped. */ | |
576 | ||
577 | static try | |
578 | mmap_flush (unix_stream * s) | |
579 | { | |
6de9cd9a DN |
580 | if (!s->mmaped) |
581 | return fd_flush (s); | |
582 | ||
583 | if (s->buffer == NULL) | |
584 | return SUCCESS; | |
585 | ||
586 | if (munmap (s->buffer, s->active)) | |
587 | return FAILURE; | |
588 | ||
589 | s->buffer = NULL; | |
590 | s->active = 0; | |
591 | ||
592 | return SUCCESS; | |
593 | } | |
594 | ||
595 | ||
596 | /* mmap_alloc()-- mmap() a section of the file. The whole section is | |
597 | * guaranteed to be mappable. */ | |
598 | ||
599 | static try | |
81f4be3c | 600 | mmap_alloc (unix_stream * s, gfc_offset where, int *len) |
6de9cd9a | 601 | { |
81f4be3c | 602 | gfc_offset offset; |
6de9cd9a DN |
603 | int length; |
604 | char *p; | |
605 | ||
606 | if (mmap_flush (s) == FAILURE) | |
607 | return FAILURE; | |
608 | ||
609 | offset = where & page_mask; /* Round down to the next page */ | |
610 | ||
611 | length = ((where - offset) & page_mask) + 2 * page_size; | |
612 | ||
613 | p = mmap (NULL, length, s->prot, MAP_SHARED, s->fd, offset); | |
614 | if (p == (char *) MAP_FAILED) | |
615 | return FAILURE; | |
616 | ||
617 | s->mmaped = 1; | |
618 | s->buffer = p; | |
619 | s->buffer_offset = offset; | |
620 | s->active = length; | |
621 | ||
622 | return SUCCESS; | |
623 | } | |
624 | ||
625 | ||
626 | static char * | |
81f4be3c | 627 | mmap_alloc_r_at (unix_stream * s, int *len, gfc_offset where) |
6de9cd9a | 628 | { |
81f4be3c | 629 | gfc_offset m; |
6de9cd9a DN |
630 | |
631 | if (where == -1) | |
632 | where = s->logical_offset; | |
633 | ||
634 | m = where + *len; | |
635 | ||
636 | if ((s->buffer == NULL || s->buffer_offset > where || | |
637 | m > s->buffer_offset + s->active) && | |
638 | mmap_alloc (s, where, len) == FAILURE) | |
639 | return NULL; | |
640 | ||
641 | if (m > s->file_length) | |
642 | { | |
643 | *len = s->file_length - s->logical_offset; | |
644 | s->logical_offset = s->file_length; | |
645 | } | |
646 | else | |
647 | s->logical_offset = m; | |
648 | ||
649 | return s->buffer + (where - s->buffer_offset); | |
650 | } | |
651 | ||
652 | ||
653 | static char * | |
81f4be3c | 654 | mmap_alloc_w_at (unix_stream * s, int *len, gfc_offset where) |
6de9cd9a DN |
655 | { |
656 | if (where == -1) | |
657 | where = s->logical_offset; | |
658 | ||
659 | /* If we're extending the file, we have to use file descriptor | |
660 | * methods. */ | |
661 | ||
662 | if (where + *len > s->file_length) | |
663 | { | |
664 | if (s->mmaped) | |
665 | mmap_flush (s); | |
666 | return fd_alloc_w_at (s, len, where); | |
667 | } | |
668 | ||
669 | if ((s->buffer == NULL || s->buffer_offset > where || | |
905d47a9 BD |
670 | where + *len > s->buffer_offset + s->active || |
671 | where < s->buffer_offset + s->active) && | |
6de9cd9a DN |
672 | mmap_alloc (s, where, len) == FAILURE) |
673 | return NULL; | |
674 | ||
675 | s->logical_offset = where + *len; | |
676 | ||
677 | return s->buffer + where - s->buffer_offset; | |
678 | } | |
679 | ||
680 | ||
681 | static int | |
81f4be3c | 682 | mmap_seek (unix_stream * s, gfc_offset offset) |
6de9cd9a | 683 | { |
6de9cd9a DN |
684 | s->logical_offset = offset; |
685 | return SUCCESS; | |
686 | } | |
687 | ||
688 | ||
689 | static try | |
690 | mmap_close (unix_stream * s) | |
691 | { | |
692 | try t; | |
693 | ||
694 | t = mmap_flush (s); | |
695 | ||
696 | if (close (s->fd) < 0) | |
697 | t = FAILURE; | |
698 | free_mem (s); | |
699 | ||
700 | return t; | |
701 | } | |
702 | ||
703 | ||
704 | static try | |
705 | mmap_sfree (unix_stream * s) | |
706 | { | |
6de9cd9a DN |
707 | return SUCCESS; |
708 | } | |
709 | ||
710 | ||
711 | /* mmap_open()-- mmap_specific open. If the particular file cannot be | |
712 | * mmap()-ed, we fall back to the file descriptor functions. */ | |
713 | ||
714 | static try | |
715 | mmap_open (unix_stream * s) | |
716 | { | |
717 | char *p; | |
718 | int i; | |
719 | ||
720 | page_size = getpagesize (); | |
721 | page_mask = ~0; | |
722 | ||
723 | p = mmap (0, page_size, s->prot, MAP_SHARED, s->fd, 0); | |
724 | if (p == (char *) MAP_FAILED) | |
725 | { | |
726 | fd_open (s); | |
727 | return SUCCESS; | |
728 | } | |
729 | ||
730 | munmap (p, page_size); | |
731 | ||
732 | i = page_size >> 1; | |
733 | while (i != 0) | |
734 | { | |
735 | page_mask <<= 1; | |
736 | i >>= 1; | |
737 | } | |
738 | ||
739 | s->st.alloc_r_at = (void *) mmap_alloc_r_at; | |
740 | s->st.alloc_w_at = (void *) mmap_alloc_w_at; | |
741 | s->st.sfree = (void *) mmap_sfree; | |
742 | s->st.close = (void *) mmap_close; | |
743 | s->st.seek = (void *) mmap_seek; | |
744 | s->st.truncate = (void *) fd_truncate; | |
745 | ||
746 | if (lseek (s->fd, s->file_length, SEEK_SET) < 0) | |
747 | return FAILURE; | |
748 | ||
749 | return SUCCESS; | |
750 | } | |
751 | ||
752 | #endif | |
753 | ||
754 | ||
755 | /********************************************************************* | |
756 | memory stream functions - These are used for internal files | |
757 | ||
758 | The idea here is that a single stream structure is created and all | |
759 | requests must be satisfied from it. The location and size of the | |
760 | buffer is the character variable supplied to the READ or WRITE | |
761 | statement. | |
762 | ||
763 | *********************************************************************/ | |
764 | ||
765 | ||
766 | static char * | |
81f4be3c | 767 | mem_alloc_r_at (unix_stream * s, int *len, gfc_offset where) |
6de9cd9a | 768 | { |
81f4be3c | 769 | gfc_offset n; |
6de9cd9a DN |
770 | |
771 | if (where == -1) | |
772 | where = s->logical_offset; | |
773 | ||
774 | if (where < s->buffer_offset || where > s->buffer_offset + s->active) | |
775 | return NULL; | |
776 | ||
6de9cd9a DN |
777 | s->logical_offset = where + *len; |
778 | ||
bd72d66c | 779 | n = s->buffer_offset + s->active - where; |
6de9cd9a DN |
780 | if (*len > n) |
781 | *len = n; | |
782 | ||
783 | return s->buffer + (where - s->buffer_offset); | |
784 | } | |
785 | ||
786 | ||
787 | static char * | |
81f4be3c | 788 | mem_alloc_w_at (unix_stream * s, int *len, gfc_offset where) |
6de9cd9a | 789 | { |
81f4be3c | 790 | gfc_offset m; |
6de9cd9a DN |
791 | |
792 | if (where == -1) | |
793 | where = s->logical_offset; | |
794 | ||
795 | m = where + *len; | |
796 | ||
797 | if (where < s->buffer_offset || m > s->buffer_offset + s->active) | |
798 | return NULL; | |
799 | ||
800 | s->logical_offset = m; | |
801 | ||
802 | return s->buffer + (where - s->buffer_offset); | |
803 | } | |
804 | ||
805 | ||
806 | static int | |
81f4be3c | 807 | mem_seek (unix_stream * s, gfc_offset offset) |
6de9cd9a | 808 | { |
6de9cd9a DN |
809 | if (offset > s->file_length) |
810 | { | |
811 | errno = ESPIPE; | |
812 | return FAILURE; | |
813 | } | |
814 | ||
815 | s->logical_offset = offset; | |
816 | return SUCCESS; | |
817 | } | |
818 | ||
819 | ||
820 | static int | |
821 | mem_truncate (unix_stream * s) | |
822 | { | |
6de9cd9a DN |
823 | return SUCCESS; |
824 | } | |
825 | ||
826 | ||
827 | static try | |
828 | mem_close (unix_stream * s) | |
829 | { | |
5615e8cd | 830 | free_mem (s); |
6de9cd9a DN |
831 | |
832 | return SUCCESS; | |
833 | } | |
834 | ||
835 | ||
836 | static try | |
837 | mem_sfree (unix_stream * s) | |
838 | { | |
6de9cd9a DN |
839 | return SUCCESS; |
840 | } | |
841 | ||
842 | ||
843 | ||
844 | /********************************************************************* | |
845 | Public functions -- A reimplementation of this module needs to | |
846 | define functional equivalents of the following. | |
847 | *********************************************************************/ | |
848 | ||
849 | /* empty_internal_buffer()-- Zero the buffer of Internal file */ | |
850 | ||
851 | void | |
852 | empty_internal_buffer(stream *strm) | |
853 | { | |
f21edfd6 RH |
854 | unix_stream * s = (unix_stream *) strm; |
855 | memset(s->buffer, ' ', s->file_length); | |
6de9cd9a DN |
856 | } |
857 | ||
858 | /* open_internal()-- Returns a stream structure from an internal file */ | |
859 | ||
860 | stream * | |
861 | open_internal (char *base, int length) | |
862 | { | |
863 | unix_stream *s; | |
864 | ||
865 | s = get_mem (sizeof (unix_stream)); | |
866 | ||
867 | s->buffer = base; | |
868 | s->buffer_offset = 0; | |
869 | ||
870 | s->logical_offset = 0; | |
871 | s->active = s->file_length = length; | |
872 | ||
873 | s->st.alloc_r_at = (void *) mem_alloc_r_at; | |
874 | s->st.alloc_w_at = (void *) mem_alloc_w_at; | |
875 | s->st.sfree = (void *) mem_sfree; | |
876 | s->st.close = (void *) mem_close; | |
877 | s->st.seek = (void *) mem_seek; | |
878 | s->st.truncate = (void *) mem_truncate; | |
879 | ||
880 | return (stream *) s; | |
881 | } | |
882 | ||
883 | ||
884 | /* fd_to_stream()-- Given an open file descriptor, build a stream | |
885 | * around it. */ | |
886 | ||
887 | static stream * | |
888 | fd_to_stream (int fd, int prot) | |
889 | { | |
890 | struct stat statbuf; | |
891 | unix_stream *s; | |
892 | ||
893 | s = get_mem (sizeof (unix_stream)); | |
894 | ||
895 | s->fd = fd; | |
896 | s->buffer_offset = 0; | |
897 | s->physical_offset = 0; | |
898 | s->logical_offset = 0; | |
899 | s->prot = prot; | |
900 | ||
901 | /* Get the current length of the file. */ | |
902 | ||
903 | fstat (fd, &statbuf); | |
904 | s->file_length = S_ISREG (statbuf.st_mode) ? statbuf.st_size : -1; | |
905 | ||
906 | #if HAVE_MMAP | |
907 | mmap_open (s); | |
908 | #else | |
909 | fd_open (s); | |
910 | #endif | |
911 | ||
912 | return (stream *) s; | |
913 | } | |
914 | ||
915 | ||
df65f093 SK |
916 | /* Given the Fortran unit number, convert it to a C file descriptor. */ |
917 | ||
918 | int | |
919 | unit_to_fd(int unit) | |
920 | { | |
df65f093 SK |
921 | gfc_unit *us; |
922 | ||
923 | us = find_unit(unit); | |
924 | if (us == NULL) | |
925 | return -1; | |
926 | ||
927 | return ((unix_stream *) us->s)->fd; | |
928 | } | |
929 | ||
930 | ||
6de9cd9a DN |
931 | /* unpack_filename()-- Given a fortran string and a pointer to a |
932 | * buffer that is PATH_MAX characters, convert the fortran string to a | |
933 | * C string in the buffer. Returns nonzero if this is not possible. */ | |
934 | ||
935 | static int | |
936 | unpack_filename (char *cstring, const char *fstring, int len) | |
937 | { | |
6de9cd9a DN |
938 | len = fstrlen (fstring, len); |
939 | if (len >= PATH_MAX) | |
940 | return 1; | |
941 | ||
942 | memmove (cstring, fstring, len); | |
943 | cstring[len] = '\0'; | |
944 | ||
945 | return 0; | |
946 | } | |
947 | ||
948 | ||
949 | /* tempfile()-- Generate a temporary filename for a scratch file and | |
950 | * open it. mkstemp() opens the file for reading and writing, but the | |
951 | * library mode prevents anything that is not allowed. The descriptor | |
41724e6a AL |
952 | * is returned, which is -1 on error. The template is pointed to by |
953 | * ioparm.file, which is copied into the unit structure | |
6de9cd9a DN |
954 | * and freed later. */ |
955 | ||
956 | static int | |
957 | tempfile (void) | |
958 | { | |
959 | const char *tempdir; | |
960 | char *template; | |
961 | int fd; | |
962 | ||
963 | tempdir = getenv ("GFORTRAN_TMPDIR"); | |
964 | if (tempdir == NULL) | |
965 | tempdir = getenv ("TMP"); | |
966 | if (tempdir == NULL) | |
967 | tempdir = DEFAULT_TEMPDIR; | |
968 | ||
969 | template = get_mem (strlen (tempdir) + 20); | |
970 | ||
41724e6a AL |
971 | st_sprintf (template, "%s/gfortrantmpXXXXXX", tempdir); |
972 | ||
973 | #ifdef HAVE_MKSTEMP | |
6de9cd9a DN |
974 | |
975 | fd = mkstemp (template); | |
976 | ||
41724e6a AL |
977 | #else /* HAVE_MKSTEMP */ |
978 | ||
979 | if (mktemp (template)) | |
980 | do | |
981 | fd = open (template, O_CREAT | O_EXCL, S_IREAD | S_IWRITE); | |
982 | while (!(fd == -1 && errno == EEXIST) && mktemp (template)); | |
983 | else | |
984 | fd = -1; | |
985 | ||
986 | #endif /* HAVE_MKSTEMP */ | |
987 | ||
6de9cd9a DN |
988 | if (fd < 0) |
989 | free_mem (template); | |
990 | else | |
991 | { | |
992 | ioparm.file = template; | |
993 | ioparm.file_len = strlen (template); /* Don't include trailing nul */ | |
994 | } | |
995 | ||
996 | return fd; | |
997 | } | |
998 | ||
999 | ||
6ecf6dcb | 1000 | /* regular_file()-- Open a regular file. |
d02b2c64 TK |
1001 | * Change flags->action if it is ACTION_UNSPECIFIED on entry, |
1002 | * unless an error occurs. | |
6ecf6dcb | 1003 | * Returns the descriptor, which is less than zero on error. */ |
6de9cd9a DN |
1004 | |
1005 | static int | |
6ecf6dcb | 1006 | regular_file (unit_flags *flags) |
6de9cd9a DN |
1007 | { |
1008 | char path[PATH_MAX + 1]; | |
6de9cd9a | 1009 | int mode; |
6ecf6dcb | 1010 | int rwflag; |
d02b2c64 | 1011 | int crflag; |
6ecf6dcb | 1012 | int fd; |
6de9cd9a DN |
1013 | |
1014 | if (unpack_filename (path, ioparm.file, ioparm.file_len)) | |
1015 | { | |
1016 | errno = ENOENT; /* Fake an OS error */ | |
1017 | return -1; | |
1018 | } | |
1019 | ||
6ecf6dcb | 1020 | rwflag = 0; |
6de9cd9a | 1021 | |
6ecf6dcb | 1022 | switch (flags->action) |
6de9cd9a DN |
1023 | { |
1024 | case ACTION_READ: | |
6ecf6dcb | 1025 | rwflag = O_RDONLY; |
6de9cd9a DN |
1026 | break; |
1027 | ||
1028 | case ACTION_WRITE: | |
6ecf6dcb | 1029 | rwflag = O_WRONLY; |
6de9cd9a DN |
1030 | break; |
1031 | ||
1032 | case ACTION_READWRITE: | |
6ecf6dcb SE |
1033 | case ACTION_UNSPECIFIED: |
1034 | rwflag = O_RDWR; | |
6de9cd9a DN |
1035 | break; |
1036 | ||
1037 | default: | |
1038 | internal_error ("regular_file(): Bad action"); | |
1039 | } | |
1040 | ||
6ecf6dcb | 1041 | switch (flags->status) |
6de9cd9a DN |
1042 | { |
1043 | case STATUS_NEW: | |
d02b2c64 | 1044 | crflag = O_CREAT | O_EXCL; |
6de9cd9a DN |
1045 | break; |
1046 | ||
d02b2c64 TK |
1047 | case STATUS_OLD: /* open will fail if the file does not exist*/ |
1048 | crflag = 0; | |
6de9cd9a DN |
1049 | break; |
1050 | ||
1051 | case STATUS_UNKNOWN: | |
1052 | case STATUS_SCRATCH: | |
d02b2c64 | 1053 | crflag = O_CREAT; |
6de9cd9a DN |
1054 | break; |
1055 | ||
1056 | case STATUS_REPLACE: | |
d02b2c64 | 1057 | crflag = O_CREAT | O_TRUNC; |
6de9cd9a DN |
1058 | break; |
1059 | ||
1060 | default: | |
1061 | internal_error ("regular_file(): Bad status"); | |
1062 | } | |
1063 | ||
6ecf6dcb | 1064 | /* rwflag |= O_LARGEFILE; */ |
6de9cd9a | 1065 | |
6ecf6dcb | 1066 | mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH; |
d02b2c64 TK |
1067 | fd = open (path, rwflag | crflag, mode); |
1068 | if (flags->action != ACTION_UNSPECIFIED) | |
1069 | return fd; | |
1070 | ||
1071 | if (fd >= 0) | |
6ecf6dcb | 1072 | { |
d02b2c64 TK |
1073 | flags->action = ACTION_READWRITE; |
1074 | return fd; | |
6ecf6dcb | 1075 | } |
d02b2c64 TK |
1076 | if (errno != EACCES) |
1077 | return fd; | |
1078 | ||
1079 | /* retry for read-only access */ | |
1080 | rwflag = O_RDONLY; | |
1081 | fd = open (path, rwflag | crflag, mode); | |
1082 | if (fd >=0) | |
1083 | { | |
1084 | flags->action = ACTION_READ; | |
1085 | return fd; /* success */ | |
1086 | } | |
1087 | ||
1088 | if (errno != EACCES) | |
1089 | return fd; /* failure */ | |
1090 | ||
1091 | /* retry for write-only access */ | |
1092 | rwflag = O_WRONLY; | |
1093 | fd = open (path, rwflag | crflag, mode); | |
1094 | if (fd >=0) | |
1095 | { | |
1096 | flags->action = ACTION_WRITE; | |
1097 | return fd; /* success */ | |
1098 | } | |
1099 | return fd; /* failure */ | |
6de9cd9a DN |
1100 | } |
1101 | ||
1102 | ||
1103 | /* open_external()-- Open an external file, unix specific version. | |
6ecf6dcb | 1104 | * Change flags->action if it is ACTION_UNSPECIFIED on entry. |
6de9cd9a DN |
1105 | * Returns NULL on operating system error. */ |
1106 | ||
1107 | stream * | |
6ecf6dcb | 1108 | open_external (unit_flags *flags) |
6de9cd9a DN |
1109 | { |
1110 | int fd, prot; | |
1111 | ||
6ecf6dcb SE |
1112 | if (flags->status == STATUS_SCRATCH) |
1113 | { | |
1114 | fd = tempfile (); | |
1115 | if (flags->action == ACTION_UNSPECIFIED) | |
1116 | flags->action = ACTION_READWRITE; | |
1117 | /* We can unlink scratch files now and it will go away when closed. */ | |
1118 | unlink (ioparm.file); | |
1119 | } | |
1120 | else | |
1121 | { | |
d02b2c64 TK |
1122 | /* regular_file resets flags->action if it is ACTION_UNSPECIFIED and |
1123 | * if it succeeds */ | |
6ecf6dcb SE |
1124 | fd = regular_file (flags); |
1125 | } | |
6de9cd9a DN |
1126 | |
1127 | if (fd < 0) | |
1128 | return NULL; | |
1129 | fd = fix_fd (fd); | |
1130 | ||
6ecf6dcb | 1131 | switch (flags->action) |
6de9cd9a DN |
1132 | { |
1133 | case ACTION_READ: | |
1134 | prot = PROT_READ; | |
1135 | break; | |
1136 | ||
1137 | case ACTION_WRITE: | |
1138 | prot = PROT_WRITE; | |
1139 | break; | |
1140 | ||
1141 | case ACTION_READWRITE: | |
1142 | prot = PROT_READ | PROT_WRITE; | |
1143 | break; | |
1144 | ||
1145 | default: | |
1146 | internal_error ("open_external(): Bad action"); | |
1147 | } | |
1148 | ||
6de9cd9a DN |
1149 | return fd_to_stream (fd, prot); |
1150 | } | |
1151 | ||
1152 | ||
1153 | /* input_stream()-- Return a stream pointer to the default input stream. | |
1154 | * Called on initialization. */ | |
1155 | ||
1156 | stream * | |
1157 | input_stream (void) | |
1158 | { | |
6de9cd9a DN |
1159 | return fd_to_stream (STDIN_FILENO, PROT_READ); |
1160 | } | |
1161 | ||
1162 | ||
1163 | /* output_stream()-- Return a stream pointer to the default input stream. | |
1164 | * Called on initialization. */ | |
1165 | ||
1166 | stream * | |
1167 | output_stream (void) | |
1168 | { | |
6de9cd9a DN |
1169 | return fd_to_stream (STDOUT_FILENO, PROT_WRITE); |
1170 | } | |
1171 | ||
1172 | ||
1173 | /* init_error_stream()-- Return a pointer to the error stream. This | |
1174 | * subroutine is called when the stream is needed, rather than at | |
1175 | * initialization. We want to work even if memory has been seriously | |
1176 | * corrupted. */ | |
1177 | ||
1178 | stream * | |
1179 | init_error_stream (void) | |
1180 | { | |
1181 | static unix_stream error; | |
1182 | ||
1183 | memset (&error, '\0', sizeof (error)); | |
1184 | ||
1185 | error.fd = options.use_stderr ? STDERR_FILENO : STDOUT_FILENO; | |
1186 | ||
1187 | error.st.alloc_w_at = (void *) fd_alloc_w_at; | |
1188 | error.st.sfree = (void *) fd_sfree; | |
1189 | ||
1190 | error.unbuffered = 1; | |
1191 | error.buffer = error.small_buffer; | |
1192 | ||
1193 | return (stream *) & error; | |
1194 | } | |
1195 | ||
1196 | ||
1197 | /* compare_file_filename()-- Given an open stream and a fortran string | |
1198 | * that is a filename, figure out if the file is the same as the | |
1199 | * filename. */ | |
1200 | ||
1201 | int | |
1202 | compare_file_filename (stream * s, const char *name, int len) | |
1203 | { | |
1204 | char path[PATH_MAX + 1]; | |
1205 | struct stat st1, st2; | |
1206 | ||
1207 | if (unpack_filename (path, name, len)) | |
1208 | return 0; /* Can't be the same */ | |
1209 | ||
1210 | /* If the filename doesn't exist, then there is no match with the | |
1211 | * existing file. */ | |
1212 | ||
1213 | if (stat (path, &st1) < 0) | |
1214 | return 0; | |
1215 | ||
1216 | fstat (((unix_stream *) s)->fd, &st2); | |
1217 | ||
1218 | return (st1.st_dev == st2.st_dev) && (st1.st_ino == st2.st_ino); | |
1219 | } | |
1220 | ||
1221 | ||
1222 | /* find_file0()-- Recursive work function for find_file() */ | |
1223 | ||
909087e0 TS |
1224 | static gfc_unit * |
1225 | find_file0 (gfc_unit * u, struct stat *st1) | |
6de9cd9a DN |
1226 | { |
1227 | struct stat st2; | |
909087e0 | 1228 | gfc_unit *v; |
6de9cd9a DN |
1229 | |
1230 | if (u == NULL) | |
1231 | return NULL; | |
1232 | ||
1233 | if (fstat (((unix_stream *) u->s)->fd, &st2) >= 0 && | |
1234 | st1->st_dev == st2.st_dev && st1->st_ino == st2.st_ino) | |
1235 | return u; | |
1236 | ||
1237 | v = find_file0 (u->left, st1); | |
1238 | if (v != NULL) | |
1239 | return v; | |
1240 | ||
1241 | v = find_file0 (u->right, st1); | |
1242 | if (v != NULL) | |
1243 | return v; | |
1244 | ||
1245 | return NULL; | |
1246 | } | |
1247 | ||
1248 | ||
1249 | /* find_file()-- Take the current filename and see if there is a unit | |
1250 | * that has the file already open. Returns a pointer to the unit if so. */ | |
1251 | ||
909087e0 | 1252 | gfc_unit * |
6de9cd9a DN |
1253 | find_file (void) |
1254 | { | |
1255 | char path[PATH_MAX + 1]; | |
1256 | struct stat statbuf; | |
1257 | ||
1258 | if (unpack_filename (path, ioparm.file, ioparm.file_len)) | |
1259 | return NULL; | |
1260 | ||
1261 | if (stat (path, &statbuf) < 0) | |
1262 | return NULL; | |
1263 | ||
1264 | return find_file0 (g.unit_root, &statbuf); | |
1265 | } | |
1266 | ||
1267 | ||
1268 | /* stream_at_bof()-- Returns nonzero if the stream is at the beginning | |
1269 | * of the file. */ | |
1270 | ||
1271 | int | |
1272 | stream_at_bof (stream * s) | |
1273 | { | |
1274 | unix_stream *us; | |
1275 | ||
1276 | us = (unix_stream *) s; | |
1277 | ||
1278 | if (!us->mmaped) | |
1279 | return 0; /* File is not seekable */ | |
1280 | ||
1281 | return us->logical_offset == 0; | |
1282 | } | |
1283 | ||
1284 | ||
1285 | /* stream_at_eof()-- Returns nonzero if the stream is at the beginning | |
1286 | * of the file. */ | |
1287 | ||
1288 | int | |
1289 | stream_at_eof (stream * s) | |
1290 | { | |
1291 | unix_stream *us; | |
1292 | ||
1293 | us = (unix_stream *) s; | |
1294 | ||
1295 | if (!us->mmaped) | |
1296 | return 0; /* File is not seekable */ | |
1297 | ||
1298 | return us->logical_offset == us->dirty_offset; | |
1299 | } | |
1300 | ||
1301 | ||
1302 | /* delete_file()-- Given a unit structure, delete the file associated | |
1303 | * with the unit. Returns nonzero if something went wrong. */ | |
1304 | ||
1305 | int | |
909087e0 | 1306 | delete_file (gfc_unit * u) |
6de9cd9a DN |
1307 | { |
1308 | char path[PATH_MAX + 1]; | |
1309 | ||
1310 | if (unpack_filename (path, u->file, u->file_len)) | |
1311 | { /* Shouldn't be possible */ | |
1312 | errno = ENOENT; | |
1313 | return 1; | |
1314 | } | |
1315 | ||
1316 | return unlink (path); | |
1317 | } | |
1318 | ||
1319 | ||
1320 | /* file_exists()-- Returns nonzero if the current filename exists on | |
1321 | * the system */ | |
1322 | ||
1323 | int | |
1324 | file_exists (void) | |
1325 | { | |
1326 | char path[PATH_MAX + 1]; | |
1327 | struct stat statbuf; | |
1328 | ||
1329 | if (unpack_filename (path, ioparm.file, ioparm.file_len)) | |
1330 | return 0; | |
1331 | ||
1332 | if (stat (path, &statbuf) < 0) | |
1333 | return 0; | |
1334 | ||
1335 | return 1; | |
1336 | } | |
1337 | ||
1338 | ||
1339 | ||
1340 | static const char *yes = "YES", *no = "NO", *unknown = "UNKNOWN"; | |
1341 | ||
1342 | /* inquire_sequential()-- Given a fortran string, determine if the | |
1343 | * file is suitable for sequential access. Returns a C-style | |
1344 | * string. */ | |
1345 | ||
1346 | const char * | |
1347 | inquire_sequential (const char *string, int len) | |
1348 | { | |
1349 | char path[PATH_MAX + 1]; | |
1350 | struct stat statbuf; | |
1351 | ||
1352 | if (string == NULL || | |
1353 | unpack_filename (path, string, len) || stat (path, &statbuf) < 0) | |
1354 | return unknown; | |
1355 | ||
1356 | if (S_ISREG (statbuf.st_mode) || | |
1357 | S_ISCHR (statbuf.st_mode) || S_ISFIFO (statbuf.st_mode)) | |
1358 | return yes; | |
1359 | ||
1360 | if (S_ISDIR (statbuf.st_mode) || S_ISBLK (statbuf.st_mode)) | |
1361 | return no; | |
1362 | ||
1363 | return unknown; | |
1364 | } | |
1365 | ||
1366 | ||
1367 | /* inquire_direct()-- Given a fortran string, determine if the file is | |
1368 | * suitable for direct access. Returns a C-style string. */ | |
1369 | ||
1370 | const char * | |
1371 | inquire_direct (const char *string, int len) | |
1372 | { | |
1373 | char path[PATH_MAX + 1]; | |
1374 | struct stat statbuf; | |
1375 | ||
1376 | if (string == NULL || | |
1377 | unpack_filename (path, string, len) || stat (path, &statbuf) < 0) | |
1378 | return unknown; | |
1379 | ||
1380 | if (S_ISREG (statbuf.st_mode) || S_ISBLK (statbuf.st_mode)) | |
1381 | return yes; | |
1382 | ||
1383 | if (S_ISDIR (statbuf.st_mode) || | |
1384 | S_ISCHR (statbuf.st_mode) || S_ISFIFO (statbuf.st_mode)) | |
1385 | return no; | |
1386 | ||
1387 | return unknown; | |
1388 | } | |
1389 | ||
1390 | ||
1391 | /* inquire_formatted()-- Given a fortran string, determine if the file | |
1392 | * is suitable for formatted form. Returns a C-style string. */ | |
1393 | ||
1394 | const char * | |
1395 | inquire_formatted (const char *string, int len) | |
1396 | { | |
1397 | char path[PATH_MAX + 1]; | |
1398 | struct stat statbuf; | |
1399 | ||
1400 | if (string == NULL || | |
1401 | unpack_filename (path, string, len) || stat (path, &statbuf) < 0) | |
1402 | return unknown; | |
1403 | ||
1404 | if (S_ISREG (statbuf.st_mode) || | |
1405 | S_ISBLK (statbuf.st_mode) || | |
1406 | S_ISCHR (statbuf.st_mode) || S_ISFIFO (statbuf.st_mode)) | |
1407 | return yes; | |
1408 | ||
1409 | if (S_ISDIR (statbuf.st_mode)) | |
1410 | return no; | |
1411 | ||
1412 | return unknown; | |
1413 | } | |
1414 | ||
1415 | ||
1416 | /* inquire_unformatted()-- Given a fortran string, determine if the file | |
1417 | * is suitable for unformatted form. Returns a C-style string. */ | |
1418 | ||
1419 | const char * | |
1420 | inquire_unformatted (const char *string, int len) | |
1421 | { | |
6de9cd9a DN |
1422 | return inquire_formatted (string, len); |
1423 | } | |
1424 | ||
1425 | ||
1426 | /* inquire_access()-- Given a fortran string, determine if the file is | |
1427 | * suitable for access. */ | |
1428 | ||
1429 | static const char * | |
1430 | inquire_access (const char *string, int len, int mode) | |
1431 | { | |
1432 | char path[PATH_MAX + 1]; | |
1433 | ||
1434 | if (string == NULL || unpack_filename (path, string, len) || | |
1435 | access (path, mode) < 0) | |
1436 | return no; | |
1437 | ||
1438 | return yes; | |
1439 | } | |
1440 | ||
1441 | ||
1442 | /* inquire_read()-- Given a fortran string, determine if the file is | |
1443 | * suitable for READ access. */ | |
1444 | ||
1445 | const char * | |
1446 | inquire_read (const char *string, int len) | |
1447 | { | |
6de9cd9a DN |
1448 | return inquire_access (string, len, R_OK); |
1449 | } | |
1450 | ||
1451 | ||
1452 | /* inquire_write()-- Given a fortran string, determine if the file is | |
1453 | * suitable for READ access. */ | |
1454 | ||
1455 | const char * | |
1456 | inquire_write (const char *string, int len) | |
1457 | { | |
6de9cd9a DN |
1458 | return inquire_access (string, len, W_OK); |
1459 | } | |
1460 | ||
1461 | ||
1462 | /* inquire_readwrite()-- Given a fortran string, determine if the file is | |
1463 | * suitable for read and write access. */ | |
1464 | ||
1465 | const char * | |
1466 | inquire_readwrite (const char *string, int len) | |
1467 | { | |
6de9cd9a DN |
1468 | return inquire_access (string, len, R_OK | W_OK); |
1469 | } | |
1470 | ||
1471 | ||
1472 | /* file_length()-- Return the file length in bytes, -1 if unknown */ | |
1473 | ||
81f4be3c | 1474 | gfc_offset |
6de9cd9a DN |
1475 | file_length (stream * s) |
1476 | { | |
6de9cd9a DN |
1477 | return ((unix_stream *) s)->file_length; |
1478 | } | |
1479 | ||
1480 | ||
1481 | /* file_position()-- Return the current position of the file */ | |
1482 | ||
81f4be3c | 1483 | gfc_offset |
6de9cd9a DN |
1484 | file_position (stream * s) |
1485 | { | |
6de9cd9a DN |
1486 | return ((unix_stream *) s)->logical_offset; |
1487 | } | |
1488 | ||
1489 | ||
1490 | /* is_seekable()-- Return nonzero if the stream is seekable, zero if | |
1491 | * it is not */ | |
1492 | ||
1493 | int | |
1494 | is_seekable (stream * s) | |
1495 | { | |
bf1df0a0 BD |
1496 | /* by convention, if file_length == -1, the file is not seekable |
1497 | note that a mmapped file is always seekable, an fd_ file may | |
1498 | or may not be. */ | |
1499 | return ((unix_stream *) s)->file_length!=-1; | |
6de9cd9a DN |
1500 | } |
1501 | ||
000aa32a JB |
1502 | try |
1503 | flush (stream *s) | |
1504 | { | |
1505 | return fd_flush( (unix_stream *) s); | |
1506 | } | |
1507 | ||
6de9cd9a DN |
1508 | |
1509 | /* How files are stored: This is an operating-system specific issue, | |
1510 | and therefore belongs here. There are three cases to consider. | |
1511 | ||
1512 | Direct Access: | |
1513 | Records are written as block of bytes corresponding to the record | |
1514 | length of the file. This goes for both formatted and unformatted | |
1515 | records. Positioning is done explicitly for each data transfer, | |
1516 | so positioning is not much of an issue. | |
1517 | ||
1518 | Sequential Formatted: | |
1519 | Records are separated by newline characters. The newline character | |
1520 | is prohibited from appearing in a string. If it does, this will be | |
1521 | messed up on the next read. End of file is also the end of a record. | |
1522 | ||
1523 | Sequential Unformatted: | |
1524 | In this case, we are merely copying bytes to and from main storage, | |
1525 | yet we need to keep track of varying record lengths. We adopt | |
1526 | the solution used by f2c. Each record contains a pair of length | |
1527 | markers: | |
1528 | ||
1529 | Length of record n in bytes | |
1530 | Data of record n | |
1531 | Length of record n in bytes | |
1532 | ||
1533 | Length of record n+1 in bytes | |
1534 | Data of record n+1 | |
1535 | Length of record n+1 in bytes | |
1536 | ||
1537 | The length is stored at the end of a record to allow backspacing to the | |
1538 | previous record. Between data transfer statements, the file pointer | |
1539 | is left pointing to the first length of the current record. | |
1540 | ||
1541 | ENDFILE records are never explicitly stored. | |
1542 | ||
1543 | */ |