1 /*
2 * Copyright (c) 2001, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 #include "jni.h"
27 #include "jni_util.h"
28 #include "jvm.h"
29 #include "io_util.h"
30 #include "io_util_md.h"
31 #include <stdio.h>
32 #include <windows.h>
33
34 #include <wchar.h>
35 #include <io.h>
36 #include <fcntl.h>
37 #include <errno.h>
38 #include <string.h>
39 #include <sys/types.h>
40 #include <sys/stat.h>
41 #include <limits.h>
42 #include <wincon.h>
43
44
45 static DWORD MAX_INPUT_EVENTS = 2000;
46
47 /* If this returns NULL then an exception is pending */
48 WCHAR*
49 fileToNTPath(JNIEnv *env, jobject file, jfieldID id) {
50 jstring path = NULL;
51 if (file != NULL) {
52 path = (*env)->GetObjectField(env, file, id);
53 }
54 return pathToNTPath(env, path, JNI_FALSE);
55 }
56
57 /* Returns the working directory for the given drive, or NULL */
58 WCHAR*
59 currentDir(int di) {
60 UINT dt;
61 WCHAR root[4];
62 // verify drive is valid as _wgetdcwd in the VC++ 2010 runtime
63 // library does not handle invalid drives.
64 root[0] = L'A' + (WCHAR)(di - 1);
65 root[1] = L':';
66 root[2] = L'\\';
67 root[3] = L'\0';
68 dt = GetDriveTypeW(root);
69 if (dt == DRIVE_UNKNOWN || dt == DRIVE_NO_ROOT_DIR) {
70 return NULL;
71 } else {
72 return _wgetdcwd(di, NULL, MAX_PATH);
73 }
74 }
75
76 /* We cache the length of current working dir here to avoid
77 calling _wgetcwd() every time we need to resolve a relative
78 path. This piece of code needs to be revisited if chdir
79 makes its way into java runtime.
80 */
81
82 int
83 currentDirLength(const WCHAR* ps, int pathlen) {
84 WCHAR *dir;
85 if (pathlen > 2 && ps[1] == L':' && ps[2] != L'\\') {
86 //drive-relative
87 WCHAR d = ps[0];
88 int dirlen = 0;
89 int di = 0;
90 if ((d >= L'a') && (d <= L'z')) di = d - L'a' + 1;
91 else if ((d >= L'A') && (d <= L'Z')) di = d - L'A' + 1;
92 else return 0; /* invalid drive name. */
93 dir = currentDir(di);
94 if (dir != NULL){
95 dirlen = (int)wcslen(dir);
96 free(dir);
97 }
98 return dirlen;
99 } else {
100 static int curDirLenCached = -1;
101 //relative to both drive and directory
102 if (curDirLenCached == -1) {
103 int dirlen = -1;
104 dir = _wgetcwd(NULL, MAX_PATH);
105 if (dir != NULL) {
106 curDirLenCached = (int)wcslen(dir);
107 free(dir);
108 }
109 }
110 return curDirLenCached;
111 }
112 }
113
114 /*
115 The "abpathlen" is the size of the buffer needed by _wfullpath. If the
116 "path" is a relative path, it is "the length of the current dir" + "the
117 length of the path", if it's "absolute" already, it's the same as
118 pathlen which is the length of "path".
119 */
120 WCHAR* prefixAbpath(const WCHAR* path, int pathlen, int abpathlen) {
121 WCHAR* pathbuf = NULL;
122 WCHAR* abpath = NULL;
123
124 abpathlen += 10; //padding
125 abpath = (WCHAR*)malloc(abpathlen * sizeof(WCHAR));
126 if (abpath) {
127 /* Collapse instances of "foo\.." and ensure absoluteness before
128 going down to prefixing.
129 */
130 if (_wfullpath(abpath, path, abpathlen)) {
131 pathbuf = getPrefixed(abpath, abpathlen);
132 } else {
133 /* _wfullpath fails if the pathlength exceeds 32k wchar.
134 Instead of doing more fancy things we simply copy the
135 ps into the return buffer, the subsequent win32 API will
136 probably fail with FileNotFoundException, which is expected
137 */
138 pathbuf = (WCHAR*)malloc((pathlen + 6) * sizeof(WCHAR));
139 if (pathbuf != 0) {
140 wcscpy(pathbuf, path);
141 }
142 }
143 free(abpath);
144 }
145 return pathbuf;
146 }
147
148 /* If this returns NULL then an exception is pending */
149 WCHAR*
150 pathToNTPath(JNIEnv *env, jstring path, jboolean throwFNFE) {
151 int pathlen = 0;
152 WCHAR *pathbuf = NULL;
153 int max_path = 248; /* CreateDirectoryW() has the limit of 248 */
154
155 WITH_UNICODE_STRING(env, path, ps) {
156 pathlen = (int)wcslen(ps);
157 if (pathlen != 0) {
158 if (pathlen > 2 &&
159 (ps[0] == L'\\' && ps[1] == L'\\' || //UNC
160 ps[1] == L':' && ps[2] == L'\\')) //absolute
161 {
162 if (pathlen > max_path - 1) {
163 pathbuf = prefixAbpath(ps, pathlen, pathlen);
164 } else {
165 pathbuf = (WCHAR*)malloc((pathlen + 6) * sizeof(WCHAR));
166 if (pathbuf != 0) {
167 wcscpy(pathbuf, ps);
168 }
169 }
170 } else {
171 /* If the path came in as a relative path, need to verify if
172 its absolute form is bigger than max_path or not, if yes
173 need to (1)convert it to absolute and (2)prefix. This is
174 obviously a burden to all relative paths (The current dir/len
175 for "drive & directory" relative path is cached, so we only
176 calculate it once but for "drive-relative path we call
177 _wgetdcwd() and wcslen() everytime), but a hit we have
178 to take if we want to support relative path beyond max_path.
179 There is no way to predict how long the absolute path will be
180 (therefor allocate the sufficient memory block) before calling
181 _wfullpath(), we have to get the length of "current" dir first.
182 */
183 WCHAR *abpath = NULL;
184 int dirlen = currentDirLength(ps, pathlen);
185 if (dirlen + pathlen + 1 > max_path - 1) {
186 pathbuf = prefixAbpath(ps, pathlen, dirlen + pathlen);
187 } else {
188 pathbuf = (WCHAR*)malloc((pathlen + 6) * sizeof(WCHAR));
189 if (pathbuf != 0) {
190 wcscpy(pathbuf, ps);
191 }
192 }
193 }
194 }
195 } END_UNICODE_STRING(env, ps);
196
197 if (pathlen == 0) {
198 if (throwFNFE == JNI_TRUE) {
199 if (!(*env)->ExceptionCheck(env)) {
200 throwFileNotFoundException(env, path);
201 }
202 return NULL;
203 } else {
204 pathbuf = (WCHAR*)malloc(sizeof(WCHAR));
205 if (pathbuf != NULL) {
206 pathbuf[0] = L'\0';
207 }
208 }
209 }
210 if (pathbuf == 0) {
211 JNU_ThrowOutOfMemoryError(env, "native memory allocation failed");
212 }
213 return pathbuf;
214 }
215
216 JNIEXPORT FD JNICALL
217 winFileHandleOpen(JNIEnv *env, jstring path, int flags)
218 {
219 const DWORD access =
220 (flags & O_WRONLY) ? GENERIC_WRITE :
221 (flags & O_RDWR) ? (GENERIC_READ | GENERIC_WRITE) :
222 GENERIC_READ;
223 const DWORD sharing =
224 FILE_SHARE_READ | FILE_SHARE_WRITE;
225 const DWORD disposition =
226 /* Note: O_TRUNC overrides O_CREAT */
227 (flags & O_TRUNC) ? CREATE_ALWAYS :
228 (flags & O_CREAT) ? OPEN_ALWAYS :
229 OPEN_EXISTING;
230 const DWORD maybeWriteThrough =
231 (flags & (O_SYNC | O_DSYNC)) ?
232 FILE_FLAG_WRITE_THROUGH :
233 FILE_ATTRIBUTE_NORMAL;
234 const DWORD maybeDeleteOnClose =
235 (flags & O_TEMPORARY) ?
236 FILE_FLAG_DELETE_ON_CLOSE :
237 FILE_ATTRIBUTE_NORMAL;
238 const DWORD flagsAndAttributes = maybeWriteThrough | maybeDeleteOnClose;
239 HANDLE h = NULL;
240
241 WCHAR *pathbuf = pathToNTPath(env, path, JNI_TRUE);
242 if (pathbuf == NULL) {
243 /* Exception already pending */
244 return -1;
245 }
246 h = CreateFileW(
247 pathbuf, /* Wide char path name */
248 access, /* Read and/or write permission */
249 sharing, /* File sharing flags */
250 NULL, /* Security attributes */
251 disposition, /* creation disposition */
252 flagsAndAttributes, /* flags and attributes */
253 NULL);
254 free(pathbuf);
255
256 if (h == INVALID_HANDLE_VALUE) {
257 throwFileNotFoundException(env, path);
258 return -1;
259 }
260 return (jlong) h;
261 }
262
263 void
264 fileOpen(JNIEnv *env, jobject this, jstring path, jfieldID fid, int flags)
265 {
266 FD h = winFileHandleOpen(env, path, flags);
267 if (h >= 0) {
268 jobject fdobj;
269 jboolean append;
270 SET_FD(this, h, fid);
271
272 fdobj = (*env)->GetObjectField(env, this, fid);
273 if (fdobj != NULL) {
274 append = (flags & O_APPEND) == 0 ? JNI_FALSE : JNI_TRUE;
275 (*env)->SetBooleanField(env, fdobj, IO_append_fdID, append);
276 }
277 }
278 }
279
280 /* These are functions that use a handle fd instead of the
281 old C style int fd as is used in HPI layer */
282
283 static int
284 handleNonSeekAvailable(FD, long *);
285 static int
286 handleStdinAvailable(FD, long *);
287
288 int
289 handleAvailable(FD fd, jlong *pbytes) {
290 HANDLE h = (HANDLE)fd;
291 DWORD type = 0;
292
293 type = GetFileType(h);
294 /* Handle is for keyboard or pipe */
295 if (type == FILE_TYPE_CHAR || type == FILE_TYPE_PIPE) {
296 int ret;
297 long lpbytes;
298 HANDLE stdInHandle = GetStdHandle(STD_INPUT_HANDLE);
299 if (stdInHandle == h) {
300 ret = handleStdinAvailable(fd, &lpbytes); /* keyboard */
301 } else {
302 ret = handleNonSeekAvailable(fd, &lpbytes); /* pipe */
303 }
304 (*pbytes) = (jlong)(lpbytes);
305 return ret;
306 }
307 /* Handle is for regular file */
308 if (type == FILE_TYPE_DISK) {
309 jlong current, end;
310
311 LARGE_INTEGER filesize;
312 current = handleLseek(fd, 0, SEEK_CUR);
313 if (current < 0) {
314 return FALSE;
315 }
316 if (GetFileSizeEx(h, &filesize) == 0) {
317 return FALSE;
318 }
319 end = long_to_jlong(filesize.QuadPart);
320 *pbytes = end - current;
321 return TRUE;
322 }
323 return FALSE;
324 }
325
326 static int
327 handleNonSeekAvailable(FD fd, long *pbytes) {
328 /* This is used for available on non-seekable devices
329 * (like both named and anonymous pipes, such as pipes
330 * connected to an exec'd process).
331 * Standard Input is a special case.
332 *
333 */
334 HANDLE han;
335
336 if ((han = (HANDLE) fd) == INVALID_HANDLE_VALUE) {
337 return FALSE;
338 }
339
340 if (! PeekNamedPipe(han, NULL, 0, NULL, pbytes, NULL)) {
341 /* PeekNamedPipe fails when at EOF. In that case we
342 * simply make *pbytes = 0 which is consistent with the
343 * behavior we get on Solaris when an fd is at EOF.
344 * The only alternative is to raise and Exception,
345 * which isn't really warranted.
346 */
347 if (GetLastError() != ERROR_BROKEN_PIPE) {
348 return FALSE;
349 }
350 *pbytes = 0;
351 }
352 return TRUE;
353 }
354
355 static int
356 handleStdinAvailable(FD fd, long *pbytes) {
357 HANDLE han;
358 DWORD numEventsRead = 0; /* Number of events read from buffer */
359 DWORD numEvents = 0; /* Number of events in buffer */
360 DWORD i = 0; /* Loop index */
361 DWORD curLength = 0; /* Position marker */
362 DWORD actualLength = 0; /* Number of bytes readable */
363 BOOL error = FALSE; /* Error holder */
364 INPUT_RECORD *lpBuffer; /* Pointer to records of input events */
365 DWORD bufferSize = 0;
366
367 if ((han = GetStdHandle(STD_INPUT_HANDLE)) == INVALID_HANDLE_VALUE) {
368 return FALSE;
369 }
370
371 /* Construct an array of input records in the console buffer */
372 error = GetNumberOfConsoleInputEvents(han, &numEvents);
373 if (error == 0) {
374 return handleNonSeekAvailable(fd, pbytes);
375 }
376
377 /* lpBuffer must fit into 64K or else PeekConsoleInput fails */
378 if (numEvents > MAX_INPUT_EVENTS) {
379 numEvents = MAX_INPUT_EVENTS;
380 }
381
382 bufferSize = numEvents * sizeof(INPUT_RECORD);
383 if (bufferSize == 0)
384 bufferSize = 1;
385 lpBuffer = malloc(bufferSize);
386 if (lpBuffer == NULL) {
387 return FALSE;
388 }
389
390 error = PeekConsoleInput(han, lpBuffer, numEvents, &numEventsRead);
391 if (error == 0) {
392 free(lpBuffer);
393 return FALSE;
394 }
395
396 /* Examine input records for the number of bytes available */
397 for(i=0; i<numEvents; i++) {
398 if (lpBuffer[i].EventType == KEY_EVENT) {
399 KEY_EVENT_RECORD *keyRecord = (KEY_EVENT_RECORD *)
400 &(lpBuffer[i].Event);
401 if (keyRecord->bKeyDown == TRUE) {
402 CHAR *keyPressed = (CHAR *) &(keyRecord->uChar);
403 curLength++;
404 if (*keyPressed == '\r')
405 actualLength = curLength;
406 }
407 }
408 }
409 if(lpBuffer != NULL)
410 free(lpBuffer);
411 *pbytes = (long) actualLength;
412 return TRUE;
413 }
414
415 /*
416 * This is documented to succeed on read-only files, but Win32's
417 * FlushFileBuffers functions fails with "access denied" in such a
418 * case. So we only signal an error if the error is *not* "access
419 * denied".
420 */
421
422 int
423 handleSync(FD fd) {
424 /*
425 * From the documentation:
426 *
427 * On Windows NT, the function FlushFileBuffers fails if hFile
428 * is a handle to console output. That is because console
429 * output is not buffered. The function returns FALSE, and
430 * GetLastError returns ERROR_INVALID_HANDLE.
431 *
432 * On the other hand, on Win95, it returns without error. I cannot
433 * assume that 0, 1, and 2 are console, because if someone closes
434 * System.out and then opens a file, they might get file descriptor
435 * 1. An error on *that* version of 1 should be reported, whereas
436 * an error on System.out (which was the original 1) should be
437 * ignored. So I use isatty() to ensure that such an error was due
438 * to this bogosity, and if it was, I ignore the error.
439 */
440
441 HANDLE handle = (HANDLE)fd;
442
443 if (!FlushFileBuffers(handle)) {
444 if (GetLastError() != ERROR_ACCESS_DENIED) { /* from winerror.h */
445 return -1;
446 }
447 }
448 return 0;
449 }
450
451 jint
452 handleSetLength(FD fd, jlong length) {
453 HANDLE h = (HANDLE)fd;
454 FILE_END_OF_FILE_INFO eofInfo;
455
456 eofInfo.EndOfFile.QuadPart = length;
457
458 if (h == INVALID_HANDLE_VALUE) {
459 return -1;
460 }
461 if (!SetFileInformationByHandle(h, FileEndOfFileInfo, &eofInfo,
462 sizeof(FILE_END_OF_FILE_INFO))) {
463 return -1;
464 }
465 return 0;
466 }
467
468 JNIEXPORT
469 jint
470 handleRead(FD fd, void *buf, jint len)
471 {
472 DWORD read = 0;
473 BOOL result = 0;
474 HANDLE h = (HANDLE)fd;
475 if (h == INVALID_HANDLE_VALUE) {
476 return -1;
477 }
478 result = ReadFile(h, /* File handle to read */
479 buf, /* address to put data */
480 len, /* number of bytes to read */
481 &read, /* number of bytes read */
482 NULL); /* no overlapped struct */
483 if (result == 0) {
484 int error = GetLastError();
485 if (error == ERROR_BROKEN_PIPE) {
486 return 0; /* EOF */
487 }
488 return -1;
489 }
490 return (jint)read;
491 }
492
493 static jint writeInternal(FD fd, const void *buf, jint len, jboolean append)
494 {
495 BOOL result = 0;
496 DWORD written = 0;
497 HANDLE h = (HANDLE)fd;
498 if (h != INVALID_HANDLE_VALUE) {
499 OVERLAPPED ov;
500 LPOVERLAPPED lpOv;
501 if (append == JNI_TRUE) {
502 ov.Offset = (DWORD)0xFFFFFFFF;
503 ov.OffsetHigh = (DWORD)0xFFFFFFFF;
504 ov.hEvent = NULL;
505 lpOv = &ov;
506 } else {
507 lpOv = NULL;
508 }
509 result = WriteFile(h, /* File handle to write */
510 buf, /* pointers to the buffers */
511 len, /* number of bytes to write */
512 &written, /* receives number of bytes written */
513 lpOv); /* overlapped struct */
514 }
515 if ((h == INVALID_HANDLE_VALUE) || (result == 0)) {
516 return -1;
517 }
518 return (jint)written;
519 }
520
521 jint handleWrite(FD fd, const void *buf, jint len) {
522 return writeInternal(fd, buf, len, JNI_FALSE);
523 }
524
525 jint handleAppend(FD fd, const void *buf, jint len) {
526 return writeInternal(fd, buf, len, JNI_TRUE);
527 }
528
529 // Function to close the fd held by this FileDescriptor and set fd to -1.
530 void
531 fileDescriptorClose(JNIEnv *env, jobject this)
532 {
533 FD fd = (*env)->GetLongField(env, this, IO_handle_fdID);
534 HANDLE h = (HANDLE)fd;
535 if ((*env)->ExceptionOccurred(env)) {
536 return;
537 }
538
539 if (h == INVALID_HANDLE_VALUE) {
540 return;
541 }
542
543 /* Set the fd to -1 before closing it so that the timing window
544 * of other threads using the wrong fd (closed but recycled fd,
545 * that gets re-opened with some other filename) is reduced.
546 * Practically the chance of its occurance is low, however, we are
547 * taking extra precaution over here.
548 */
549 (*env)->SetLongField(env, this, IO_handle_fdID, -1);
550 if ((*env)->ExceptionOccurred(env)) {
551 return;
552 }
553
554 if (CloseHandle(h) == 0) { /* Returns zero on failure */
555 JNU_ThrowIOExceptionWithLastError(env, "close failed");
556 }
557 }
558
559 JNIEXPORT jlong JNICALL
560 handleLseek(FD fd, jlong offset, jint whence)
561 {
562 LARGE_INTEGER pos, distance;
563 DWORD lowPos = 0;
564 long highPos = 0;
565 DWORD op = FILE_CURRENT;
566 HANDLE h = (HANDLE)fd;
567
568 if (whence == SEEK_END) {
569 op = FILE_END;
570 }
571 if (whence == SEEK_CUR) {
572 op = FILE_CURRENT;
573 }
574 if (whence == SEEK_SET) {
575 op = FILE_BEGIN;
576 }
577
578 distance.QuadPart = offset;
579 if (SetFilePointerEx(h, distance, &pos, op) == 0) {
580 return -1;
581 }
582 return long_to_jlong(pos.QuadPart);
583 }
584
585 jlong
586 handleGetLength(FD fd) {
587 HANDLE h = (HANDLE) fd;
588 LARGE_INTEGER length;
589 if (GetFileSizeEx(h, &length) != 0) {
590 return long_to_jlong(length.QuadPart);
591 } else {
592 return -1;
593 }
594 }