xref: /titanic_41/usr/src/lib/libcmdutils/common/writefile.c (revision d29f5a711240f866521445b1656d114da090335e)
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 2008 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  * University Copyright- Copyright (c) 1982, 1986, 1988
32  * The Regents of the University of California
33  * All Rights Reserved
34  *
35  * University Acknowledgment- Portions of this document are derived from
36  * software developed by the University of California, Berkeley, and its
37  * contributors.
38  */
39 
40 #pragma ident	"%Z%%M%	%I%	%E% SMI"
41 
42 #include "libcmdutils.h"
43 
44 
45 int
46 writefile(int fi, int fo, char *infile, char *outfile, char *asfile,
47     char *atfile, struct stat *s1p, struct stat *s2p)
48 {
49 	int mapsize, munmapsize;
50 	caddr_t cp;
51 	off_t filesize = s1p->st_size;
52 	off_t offset;
53 	int nbytes;
54 	int remains;
55 	int n;
56 	size_t src_size;
57 	size_t targ_size;
58 	char *srcbuf;
59 	char *targbuf;
60 
61 	if (asfile != NULL) {
62 		src_size = strlen(infile) + strlen(asfile) +
63 		    strlen(dgettext(TEXT_DOMAIN, " attribute ")) + 1;
64 	} else {
65 		src_size = strlen(infile) + 1;
66 	}
67 	srcbuf = malloc(src_size);
68 	if (srcbuf == NULL) {
69 		(void) fprintf(stderr,
70 		    dgettext(TEXT_DOMAIN, "could not allocate memory"
71 		    " for path buffer: "));
72 		return (1);
73 	}
74 	if (asfile != NULL) {
75 		(void) snprintf(srcbuf, src_size, "%s%s%s",
76 		    infile, dgettext(TEXT_DOMAIN, " attribute "), asfile);
77 	} else {
78 		(void) snprintf(srcbuf, src_size, "%s", infile);
79 	}
80 
81 	if (atfile != NULL) {
82 		targ_size = strlen(outfile) + strlen(atfile) +
83 		    strlen(dgettext(TEXT_DOMAIN, " attribute ")) + 1;
84 	} else {
85 		targ_size = strlen(outfile) + 1;
86 	}
87 	targbuf = malloc(targ_size);
88 	if (targbuf == NULL) {
89 		(void) fprintf(stderr,
90 		    dgettext(TEXT_DOMAIN, "could not allocate memory"
91 		    " for path buffer: "));
92 		return (1);
93 	}
94 	if (atfile != NULL) {
95 		(void) snprintf(targbuf, targ_size, "%s%s%s",
96 		    outfile, dgettext(TEXT_DOMAIN, " attribute "), atfile);
97 	} else {
98 		(void) snprintf(targbuf, targ_size, "%s", outfile);
99 	}
100 
101 	if (ISREG(*s1p) && s1p->st_size > SMALLFILESIZE) {
102 		/*
103 		 * Determine size of initial mapping.  This will determine the
104 		 * size of the address space chunk we work with.  This initial
105 		 * mapping size will be used to perform munmap() in the future.
106 		 */
107 		mapsize = MAXMAPSIZE;
108 		if (s1p->st_size < mapsize) mapsize = s1p->st_size;
109 		munmapsize = mapsize;
110 
111 		/*
112 		 * Mmap time!
113 		 */
114 		if ((cp = mmap((caddr_t)NULL, mapsize, PROT_READ,
115 		    MAP_SHARED, fi, (off_t)0)) == MAP_FAILED)
116 			mapsize = 0;   /* can't mmap today */
117 	} else
118 		mapsize = 0;
119 
120 	if (mapsize != 0) {
121 		offset = 0;
122 
123 		for (;;) {
124 			nbytes = write(fo, cp, mapsize);
125 			/*
126 			 * if we write less than the mmaped size it's due to a
127 			 * media error on the input file or out of space on
128 			 * the output file.  So, try again, and look for errno.
129 			 */
130 			if ((nbytes >= 0) && (nbytes != (int)mapsize)) {
131 				remains = mapsize - nbytes;
132 				while (remains > 0) {
133 					nbytes = write(fo,
134 					    cp + mapsize - remains, remains);
135 					if (nbytes < 0) {
136 						if (errno == ENOSPC)
137 							perror(targbuf);
138 						else
139 							perror(srcbuf);
140 						(void) close(fi);
141 						(void) close(fo);
142 						(void) munmap(cp, munmapsize);
143 						if (ISREG(*s2p))
144 							(void) unlink(targbuf);
145 						return (1);
146 					}
147 					remains -= nbytes;
148 					if (remains == 0)
149 						nbytes = mapsize;
150 				}
151 			}
152 			/*
153 			 * although the write manual page doesn't specify this
154 			 * as a possible errno, it is set when the nfs read
155 			 * via the mmap'ed file is accessed, so report the
156 			 * problem as a source access problem, not a target file
157 			 * problem
158 			 */
159 			if (nbytes < 0) {
160 				if (errno == EACCES)
161 					perror(srcbuf);
162 				else
163 					perror(targbuf);
164 				(void) close(fi);
165 				(void) close(fo);
166 				(void) munmap(cp, munmapsize);
167 				if (ISREG(*s2p))
168 					(void) unlink(targbuf);
169 				if (srcbuf != NULL)
170 					free(srcbuf);
171 				if (targbuf != NULL)
172 					free(targbuf);
173 				return (1);
174 			}
175 			filesize -= nbytes;
176 			if (filesize == 0)
177 				break;
178 			offset += nbytes;
179 			if (filesize < mapsize)
180 				mapsize = filesize;
181 			if (mmap(cp, mapsize, PROT_READ, MAP_SHARED |
182 			    MAP_FIXED, fi, offset) == MAP_FAILED) {
183 				perror(srcbuf);
184 				(void) close(fi);
185 				(void) close(fo);
186 				(void) munmap(cp, munmapsize);
187 				if (ISREG(*s2p))
188 					(void) unlink(targbuf);
189 				if (srcbuf != NULL)
190 					free(srcbuf);
191 				if (targbuf != NULL)
192 					free(targbuf);
193 				return (1);
194 			}
195 		}
196 		(void) munmap(cp, munmapsize);
197 	} else {
198 		char buf[SMALLFILESIZE];
199 		for (;;) {
200 			n = read(fi, buf, sizeof (buf));
201 			if (n == 0) {
202 				return (0);
203 			} else if (n < 0) {
204 				(void) close(fi);
205 				(void) close(fo);
206 				if (ISREG(*s2p))
207 					(void) unlink(targbuf);
208 				if (srcbuf != NULL)
209 					free(srcbuf);
210 				if (targbuf != NULL)
211 					free(targbuf);
212 				return (1);
213 			} else if (write(fo, buf, n) != n) {
214 				(void) close(fi);
215 				(void) close(fo);
216 				if (ISREG(*s2p))
217 					(void) unlink(targbuf);
218 				if (srcbuf != NULL)
219 					free(srcbuf);
220 				if (targbuf != NULL)
221 					free(targbuf);
222 				return (1);
223 			}
224 		}
225 	}
226 	if (srcbuf != NULL)
227 		free(srcbuf);
228 	if (targbuf != NULL)
229 		free(targbuf);
230 	return (0);
231 }
232