xref: /titanic_51/usr/src/cmd/svr4pkg/libinst/copyf.c (revision a31148363f598def767ac48c5d82e1572e44b935)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29 
30 
31 
32 #include <stdio.h>
33 #include <string.h>
34 #include <errno.h>
35 #include <stdlib.h>
36 #include <unistd.h>
37 #include <libgen.h>
38 #include <fcntl.h>
39 #include <sys/types.h>
40 #include <utime.h>
41 #include <sys/stat.h>
42 #include <locale.h>
43 #include <libintl.h>
44 #include <sys/mman.h>
45 
46 /*
47  * consolidation pkg command library includes
48  */
49 
50 #include "pkglib.h"
51 
52 /*
53  * local pkg command library includes
54  */
55 #include "libinst.h"
56 #include "libadm.h"
57 #include "messages.h"
58 
59 /*
60  * MAXMAPSIZE controls the largest mapping to use at a time; please refer
61  * to mmap(2) for details of how this size is incremented and rounded; briefly
62  * each mapping request has an additional 16Kb added to it - mappings over
63  * 4Mb will be rounded to a 4Mb boundary - thus if there were 8mb, adding
64  * in the 16Kb overhead the mapping would use another 4Mb-16kb - that is
65  * why there is 16Kb subtracted from the total
66  */
67 
68 #define	MAXMAPSIZE	(1024*1024*8)-(1024*16)	/* map at most 8MB */
69 #define	SMALLFILESIZE	(32*1024)	/* dont mmap files less than 32kb */
70 
71 /*
72  * Name:	copyF
73  * Description:	fast copy of file - use mmap()/write() loop if possible
74  * Arguments:	char *srcPath - name of source file to copy from
75  *		char *dstPath - name of target file to copy to
76  *		time_t a_mytime: control setting of access/modification times:
77  *			== 0 - replicate source file access/modification times
78  *			!= 0 - use specified time for access/modification times
79  * Returns:	int
80  *		== 0 - successful
81  *		!= 0 - failure
82  */
83 
84 int
85 copyf(char *a_srcPath, char *a_dstPath, time_t a_mytime)
86 {
87 	struct stat	srcStatbuf;
88 	struct utimbuf	times;
89 	int		srcFd;
90 	int		dstFd;
91 	int		status;
92 	char		*pt;
93 
94 	/* open source file for reading */
95 
96 	srcFd = open(a_srcPath, O_RDONLY, 0);
97 	if (srcFd < 0) {
98 		progerr(ERR_OPEN_READ, a_srcPath, errno, strerror(errno));
99 		return (-1);
100 	}
101 
102 	/* obtain file status of source file */
103 
104 	if (fstat(srcFd, &srcStatbuf) != 0) {
105 		progerr(ERR_FSTAT, srcFd, a_srcPath, errno, strerror(errno));
106 		(void) close(srcFd);
107 		return (-1);
108 	}
109 
110 	/* open target file for writing */
111 
112 	dstFd = open(a_dstPath, O_WRONLY | O_TRUNC | O_CREAT,
113 		srcStatbuf.st_mode);
114 	if (dstFd < 0) {
115 		/* create directory structure if missing */
116 		pt = a_dstPath;
117 		while (pt = strchr(pt+1, '/')) {
118 			*pt = '\0';
119 			if (isdir(a_dstPath)) {
120 				if (mkdir(a_dstPath, 0755)) {
121 					progerr(ERR_NODIR, a_dstPath,
122 						errno, strerror(errno));
123 					*pt = '/';
124 					(void) close(srcFd);
125 					return (-1);
126 				}
127 			}
128 			*pt = '/';
129 		}
130 
131 		/* attempt to create target file again */
132 		dstFd = open(a_dstPath, O_WRONLY | O_TRUNC | O_CREAT,
133 				srcStatbuf.st_mode);
134 		if (dstFd < 0) {
135 			progerr(ERR_OPEN_WRITE, a_dstPath, errno,
136 							strerror(errno));
137 			(void) close(srcFd);
138 			return (-1);
139 		}
140 	}
141 
142 	/*
143 	 * source and target files are open: copy data
144 	 */
145 
146 	status = copyFile(srcFd, dstFd, a_srcPath, a_dstPath, &srcStatbuf, 0);
147 
148 	(void) close(srcFd);
149 	(void) close(dstFd);
150 
151 	/*
152 	 * determine how to set access/modification times for target:
153 	 * -- a_mytime == 0: replicate source file access/modification times
154 	 * -- otherwise: use a_mytime for file access/modification times
155 	 */
156 
157 	if (a_mytime == 0) {
158 		times.actime = srcStatbuf.st_atime;
159 		times.modtime = srcStatbuf.st_mtime;
160 	} else {
161 		times.actime = a_mytime;
162 		times.modtime = a_mytime;
163 	}
164 
165 	/* set access/modification times for target */
166 
167 	if (utime(a_dstPath, &times) != 0) {
168 		progerr(ERR_MODTIM, a_dstPath, errno, strerror(errno));
169 		return (-1);
170 	}
171 
172 	/* return error if copy failed */
173 
174 	if (status != 0) {
175 		progerr(ERR_READ, a_srcPath, errno, strerror(errno));
176 		return (-1);
177 	}
178 
179 	/* success! */
180 
181 	return (0);
182 }
183 
184 /*
185  * Name:	copyFile
186  * Description:	fast copy of file - use mmap()/write() loop if possible
187  * Arguments:	int srcFd - file descriptor open on source file
188  *		int dstFd - file descriptor open on target file
189  *		char *srcPath - name of source file (for error messages)
190  *		char *dstPath - name of target file (for error messages)
191  *		struct stat *a_srcStatbuf - stat structure for source file
192  *		long a_iosize - preferred io size for read/write loop
193  * Returns:	int
194  *		== 0 - successful
195  *		!= 0 - failure
196  */
197 
198 int
199 copyFile(int a_srcFd, int a_dstFd, char *a_srcPath, char *a_dstPath,
200 	struct stat *a_srcStatbuf, long a_iosize)
201 {
202 	caddr_t	cp;
203 	off_t	filesize = a_srcStatbuf->st_size;
204 	size_t	mapsize = 0;
205 	size_t	munmapsize = 0;
206 	off_t	offset = 0;
207 
208 	echoDebug(DBG_COPY_FILE, a_srcPath, a_dstPath);
209 
210 	/*
211 	 * if the source is a regular file and is not "too small", then cause
212 	 * the file to be mapped into memory
213 	 */
214 
215 	if (S_ISREG(a_srcStatbuf->st_mode) && (filesize > SMALLFILESIZE)) {
216 		/*
217 		 * Determine size of initial mapping.  This will determine the
218 		 * size of the address space chunk we work with.  This initial
219 		 * mapping size will be used to perform munmap() in the future.
220 		 */
221 
222 		mapsize = MAXMAPSIZE;
223 		if (filesize < mapsize) {
224 			mapsize = filesize;
225 		}
226 
227 		/*
228 		 * remember size of mapping to "unmap" - if the source file
229 		 * exceeds MAXMAPSIZE bytes, then the final mapping of the
230 		 * source file will be less than MAXMAPSIZE, and we need to
231 		 * make sure that the entire mapping is unmapped when done.
232 		 */
233 
234 		munmapsize = mapsize;
235 
236 		/* map the first segment of the source into memory */
237 
238 		cp = mmap((caddr_t)NULL, mapsize, PROT_READ,
239 			(MAP_SHARED|MAP_ALIGN), a_srcFd, (off_t)0);
240 		if (cp == MAP_FAILED) {
241 			mapsize = 0;   /* can't mmap today */
242 		}
243 	}
244 
245 	/*
246 	 * if the source was not mapped into memory, copy via read/write loop
247 	 */
248 
249 	if (mapsize == 0) {
250 		char	*buf = (char *)NULL;
251 		size_t	blocksize;
252 		int	pagesize = getpagesize();
253 
254 		/* set blocksize for copy */
255 
256 		blocksize = a_iosize;
257 		if ((blocksize == 0) || (blocksize > SMALLFILESIZE)) {
258 			blocksize = SMALLFILESIZE;
259 		} else if (blocksize < pagesize) {
260 			blocksize = pagesize;
261 		}
262 
263 		/* allocate i/o transfer buffer */
264 
265 		buf = memalign((size_t)pagesize, blocksize);
266 		if (buf == (char *)NULL) {
267 			progerr(ERR_COPY_MEMORY, a_srcPath, errno,
268 				strerror(errno));
269 			return (1);
270 		}
271 
272 		/* copy the file contents */
273 
274 		for (;;) {
275 			ssize_t	n;
276 
277 			/* read next block of data */
278 
279 			n = read(a_srcFd, buf, blocksize);
280 			if (n == 0) {
281 				/* end of file - return success */
282 				(void) free(buf);
283 				return (0);
284 			} else if (n < 0) {
285 				/* read error - return error */
286 				progerr(ERR_READ, a_srcPath,
287 						errno, strerror(errno));
288 				(void) free(buf);
289 				return (1);
290 			}
291 
292 			/* write out block of data just read in */
293 
294 			if (vfpSafeWrite(a_dstFd, buf, (size_t)n) != n) {
295 				/* short write/write error - return error */
296 				progerr(ERR_WRITE, a_dstPath,
297 						errno, strerror(errno));
298 				(void) free(buf);
299 				return (1);
300 			}
301 		}
302 	}
303 
304 	/*
305 	 * the source has been mapped into memory, copy via mappings
306 	 */
307 
308 	for (;;) {
309 		ssize_t	nbytes;
310 
311 		/* write first mappings worth of data */
312 
313 		nbytes = write(a_dstFd, cp, mapsize);
314 
315 		/*
316 		 * if we write less than the mmaped size it's due to a
317 		 * media error on the input file or out of space on
318 		 * the output file.  So, try again, and look for errno.
319 		 */
320 
321 		if ((nbytes >= 0) && (nbytes != (ssize_t)mapsize)) {
322 			size_t	remains;
323 
324 			remains = mapsize - nbytes;
325 			while (remains > 0) {
326 				nbytes = write(a_dstFd,
327 					(cp + mapsize - remains), remains);
328 				if (nbytes >= 0) {
329 					remains -= nbytes;
330 					if (remains == 0) {
331 						nbytes = mapsize;
332 					}
333 					continue;
334 				}
335 
336 				/* i/o error - report and exit */
337 
338 				if (errno == ENOSPC) {
339 					progerr(ERR_WRITE, a_dstPath,
340 						errno, strerror(errno));
341 				} else {
342 					progerr(ERR_READ, a_srcPath,
343 						errno, strerror(errno));
344 				}
345 
346 				/* unmap source file mapping */
347 				(void) munmap(cp, munmapsize);
348 				return (1);
349 			}
350 		}
351 
352 		/*
353 		 * although the write manual page doesn't specify this
354 		 * as a possible errno, it is set when the nfs read
355 		 * via the mmap'ed file is accessed, so report the
356 		 * problem as a source access problem, not a target file
357 		 * problem
358 		 */
359 
360 		if (nbytes < 0) {
361 			if (errno == EACCES) {
362 				progerr(ERR_READ, a_srcPath,
363 					errno, strerror(errno));
364 			} else {
365 				progerr(ERR_WRITE, a_dstPath,
366 					errno, strerror(errno));
367 			}
368 
369 			/* unmap source file mapping */
370 			(void) munmap(cp, munmapsize);
371 			return (1);
372 		}
373 
374 		filesize -= nbytes;
375 		if (filesize == 0) {
376 			break;
377 		}
378 
379 		offset += nbytes;
380 		if (filesize < mapsize) {
381 			mapsize = filesize;
382 		}
383 
384 		/* map next segment of file on top of existing mapping */
385 
386 		cp = mmap(cp, mapsize, PROT_READ, (MAP_SHARED|MAP_FIXED),
387 			a_srcFd, offset);
388 
389 		if (cp == MAP_FAILED) {
390 			progerr(ERR_MAPFAILED, a_srcPath, errno,
391 						strerror(errno));
392 			/* unmap source file mapping */
393 			(void) munmap(cp, munmapsize);
394 			return (1);
395 		}
396 	}
397 
398 	/* unmap source file mapping */
399 
400 	(void) munmap(cp, munmapsize);
401 
402 	return (0);
403 }
404 
405 /*
406  * Name:	openLocal
407  * Description:	open a file and assure that the descriptor returned is open on
408  *		a file that is local to the current system - if the file is not
409  *		local to this system, copy the file to a temporary file first,
410  *		and then pass a handle back opened on the temporary file
411  * Arguments:	a_path - [RO, *RO] - (char *)
412  *			Pointer to string representing the path to the file
413  *			to open
414  *		a_oflag - [RO, *RO] - (int)
415  *			Integer representing the "mode" bits for an open(2) call
416  *		a_tmpdir - [RO, *RO] - (char *)
417  *			Pointer to string representing the path to a directory
418  *			where a temporary copy of the file can be placed if
419  *			the source file is not local to this system. If this is
420  *			NULL or does not exist, P_tmpdir is used.
421  * Returns:	int
422  *			>= 0 - file descriptor opened on the file
423  *			== -1 - failed to open - errno contains error code
424  * NOTE:	If the file is not local and is copied locally, the file is
425  *		setup in such a way that it will be removed when the last
426  *		file descriptor opened on the file is closed - there is no need
427  *		to know the path to the temporary file or to remove it
428  *		when done.
429  */
430 
431 int
432 openLocal(char *a_path, int a_oflag, char *a_tmpdir)
433 {
434 	char		*bn;
435 	char		template[PATH_MAX];
436 	int		fd;
437 	int		lerrno;
438 	int		n;
439 	int		tmpFd;
440 	struct stat	statbuf;
441 
442 	/* open source file */
443 
444 	fd = open(a_path, a_oflag);
445 	if (fd < 0) {
446 		return (fd);
447 	}
448 
449 	/* return open fd if the source file is not remote */
450 
451 	if (!isFdRemote(fd)) {
452 		return (fd);
453 	}
454 
455 	/*
456 	 * source file is remote - must make a local copy
457 	 */
458 
459 	/* get the source file's status */
460 
461 	n = fstat(fd, &statbuf);
462 	if (n < 0) {
463 		lerrno = errno;
464 		(void) close(fd);
465 		errno = lerrno;
466 		return (-1);
467 	}
468 
469 	/* generate unique temporary file name */
470 
471 	if ((a_tmpdir == (char *)NULL) || (*a_tmpdir == '\0') ||
472 		(isdir(a_tmpdir) != 0)) {
473 		a_tmpdir = P_tmpdir;
474 	}
475 	bn = basename(a_path);
476 	n = strlen(a_tmpdir);
477 	n = snprintf(template, sizeof (template), "%s%s%sXXXXXX",
478 		a_tmpdir, a_tmpdir[n-1] == '/' ? "" : "/", bn);
479 	if (n > sizeof (template)) {
480 		(void) close(fd);
481 		return (EINVAL);
482 	}
483 
484 	/* create the temporary file and open it */
485 
486 	tmpFd = mkstemp(template);
487 	if (tmpFd < 0) {
488 		lerrno = errno;
489 		(void) close(fd);
490 		errno = lerrno;
491 		return (tmpFd);
492 	}
493 
494 	/* unlink the file so when it is closed it is automatically deleted */
495 
496 	(void) unlink(template);
497 
498 	/* copy the source file to the temporary file */
499 
500 	n = copyFile(fd, tmpFd, a_path, template, &statbuf, 0L);
501 	lerrno = errno;
502 	(void) close(fd);
503 	if (n != 0) {
504 		(void) close(tmpFd);
505 		errno = lerrno;
506 		return (-1);
507 	}
508 
509 	/* return handle to temporary file created */
510 
511 	return (tmpFd);
512 }
513