source: MondoRescue/branches/3.3/mindi-busybox/archival/libarchive/data_extract_all.c@ 3770

Last change on this file since 3770 was 3621, checked in by Bruno Cornec, 9 years ago

New 3?3 banch for incorporation of latest busybox 1.25. Changing minor version to handle potential incompatibilities.
  • Property svn:eol-style set to native
File size: 6.7 KB
Line 
1/* vi: set sw=4 ts=4: */
2/*
3 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
4 */
5
6#include "libbb.h"
7#include "bb_archive.h"
8
9void FAST_FUNC data_extract_all(archive_handle_t *archive_handle)
10{
11 file_header_t *file_header = archive_handle->file_header;
12 int dst_fd;
13 int res;
14 char *hard_link;
15#if ENABLE_FEATURE_TAR_LONG_OPTIONS
16 char *dst_name;
17#else
18# define dst_name (file_header->name)
19#endif
20
21#if ENABLE_FEATURE_TAR_SELINUX
22 char *sctx = archive_handle->tar__sctx[PAX_NEXT_FILE];
23 if (!sctx)
24 sctx = archive_handle->tar__sctx[PAX_GLOBAL];
25 if (sctx) { /* setfscreatecon is 4 syscalls, avoid if possible */
26 setfscreatecon(sctx);
27 free(archive_handle->tar__sctx[PAX_NEXT_FILE]);
28 archive_handle->tar__sctx[PAX_NEXT_FILE] = NULL;
29 }
30#endif
31
32 /* Hard links are encoded as regular files of size 0
33 * with a nonempty link field */
34 hard_link = NULL;
35 if (S_ISREG(file_header->mode) && file_header->size == 0)
36 hard_link = file_header->link_target;
37
38#if ENABLE_FEATURE_TAR_LONG_OPTIONS
39 dst_name = file_header->name;
40 if (archive_handle->tar__strip_components) {
41 unsigned n = archive_handle->tar__strip_components;
42 do {
43 dst_name = strchr(dst_name, '/');
44 if (!dst_name || dst_name[1] == '\0') {
45 data_skip(archive_handle);
46 goto ret;
47 }
48 dst_name++;
49 /*
50 * Link target is shortened only for hardlinks:
51 * softlinks restored unchanged.
52 */
53 if (hard_link) {
54// GNU tar 1.26 does not check that we reached end of link name:
55// if "dir/hardlink" is hardlinked to "file",
56// tar xvf a.tar --strip-components=1 says:
57// tar: hardlink: Cannot hard link to '': No such file or directory
58// and continues processing. We silently skip such entries.
59 hard_link = strchr(hard_link, '/');
60 if (!hard_link || hard_link[1] == '\0') {
61 data_skip(archive_handle);
62 goto ret;
63 }
64 hard_link++;
65 }
66 } while (--n != 0);
67 }
68#endif
69
70 if (archive_handle->ah_flags & ARCHIVE_CREATE_LEADING_DIRS) {
71 char *slash = strrchr(dst_name, '/');
72 if (slash) {
73 *slash = '\0';
74 bb_make_directory(dst_name, -1, FILEUTILS_RECUR);
75 *slash = '/';
76 }
77 }
78
79 if (archive_handle->ah_flags & ARCHIVE_UNLINK_OLD) {
80 /* Remove the entry if it exists */
81 if (!S_ISDIR(file_header->mode)) {
82 if (hard_link) {
83 /* Ugly special case:
84 * tar cf t.tar hardlink1 hardlink2 hardlink1
85 * results in this tarball structure:
86 * hardlink1
87 * hardlink2 -> hardlink1
88 * hardlink1 -> hardlink1 <== !!!
89 */
90 if (strcmp(hard_link, dst_name) == 0)
91 goto ret;
92 }
93 /* Proceed with deleting */
94 if (unlink(dst_name) == -1
95 && errno != ENOENT
96 ) {
97 bb_perror_msg_and_die("can't remove old file %s",
98 dst_name);
99 }
100 }
101 }
102 else if (archive_handle->ah_flags & ARCHIVE_EXTRACT_NEWER) {
103 /* Remove the existing entry if its older than the extracted entry */
104 struct stat existing_sb;
105 if (lstat(dst_name, &existing_sb) == -1) {
106 if (errno != ENOENT) {
107 bb_perror_msg_and_die("can't stat old file");
108 }
109 }
110 else if (existing_sb.st_mtime >= file_header->mtime) {
111 if (!(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)
112 && !S_ISDIR(file_header->mode)
113 ) {
114 bb_error_msg("%s not created: newer or "
115 "same age file exists", dst_name);
116 }
117 data_skip(archive_handle);
118 goto ret;
119 }
120 else if ((unlink(dst_name) == -1) && (errno != EISDIR)) {
121 bb_perror_msg_and_die("can't remove old file %s",
122 dst_name);
123 }
124 }
125
126 /* Handle hard links separately */
127 if (hard_link) {
128 res = link(hard_link, dst_name);
129 if (res != 0 && !(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)) {
130 bb_perror_msg("can't create %slink "
131 "from %s to %s", "hard",
132 dst_name,
133 hard_link);
134 }
135 /* Hardlinks have no separate mode/ownership, skip chown/chmod */
136 goto ret;
137 }
138
139 /* Create the filesystem entry */
140 switch (file_header->mode & S_IFMT) {
141 case S_IFREG: {
142 /* Regular file */
143 char *dst_nameN;
144 int flags = O_WRONLY | O_CREAT | O_EXCL;
145 if (archive_handle->ah_flags & ARCHIVE_O_TRUNC)
146 flags = O_WRONLY | O_CREAT | O_TRUNC;
147 dst_nameN = dst_name;
148#ifdef ARCHIVE_REPLACE_VIA_RENAME
149 if (archive_handle->ah_flags & ARCHIVE_REPLACE_VIA_RENAME)
150 /* rpm-style temp file name */
151 dst_nameN = xasprintf("%s;%x", dst_name, (int)getpid());
152#endif
153 dst_fd = xopen3(dst_nameN,
154 flags,
155 file_header->mode
156 );
157 bb_copyfd_exact_size(archive_handle->src_fd, dst_fd, file_header->size);
158 close(dst_fd);
159#ifdef ARCHIVE_REPLACE_VIA_RENAME
160 if (archive_handle->ah_flags & ARCHIVE_REPLACE_VIA_RENAME) {
161 xrename(dst_nameN, dst_name);
162 free(dst_nameN);
163 }
164#endif
165 break;
166 }
167 case S_IFDIR:
168 res = mkdir(dst_name, file_header->mode);
169 if ((res == -1)
170 && (errno != EISDIR) /* btw, Linux doesn't return this */
171 && (errno != EEXIST)
172 && !(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)
173 ) {
174 bb_perror_msg("can't make dir %s", dst_name);
175 }
176 break;
177 case S_IFLNK:
178 /* Symlink */
179//TODO: what if file_header->link_target == NULL (say, corrupted tarball?)
180 res = symlink(file_header->link_target, dst_name);
181 if (res != 0
182 && !(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)
183 ) {
184 bb_perror_msg("can't create %slink "
185 "from %s to %s", "sym",
186 dst_name,
187 file_header->link_target);
188 }
189 break;
190 case S_IFSOCK:
191 case S_IFBLK:
192 case S_IFCHR:
193 case S_IFIFO:
194 res = mknod(dst_name, file_header->mode, file_header->device);
195 if ((res == -1)
196 && !(archive_handle->ah_flags & ARCHIVE_EXTRACT_QUIET)
197 ) {
198 bb_perror_msg("can't create node %s", dst_name);
199 }
200 break;
201 default:
202 bb_error_msg_and_die("unrecognized file type");
203 }
204
205 if (!S_ISLNK(file_header->mode)) {
206 if (!(archive_handle->ah_flags & ARCHIVE_DONT_RESTORE_OWNER)) {
207 uid_t uid = file_header->uid;
208 gid_t gid = file_header->gid;
209#if ENABLE_FEATURE_TAR_UNAME_GNAME
210 if (!(archive_handle->ah_flags & ARCHIVE_NUMERIC_OWNER)) {
211 if (file_header->tar__uname) {
212//TODO: cache last name/id pair?
213 struct passwd *pwd = getpwnam(file_header->tar__uname);
214 if (pwd) uid = pwd->pw_uid;
215 }
216 if (file_header->tar__gname) {
217 struct group *grp = getgrnam(file_header->tar__gname);
218 if (grp) gid = grp->gr_gid;
219 }
220 }
221#endif
222 /* GNU tar 1.15.1 uses chown, not lchown */
223 chown(dst_name, uid, gid);
224 }
225 /* uclibc has no lchmod, glibc is even stranger -
226 * it has lchmod which seems to do nothing!
227 * so we use chmod... */
228 if (!(archive_handle->ah_flags & ARCHIVE_DONT_RESTORE_PERM)) {
229 chmod(dst_name, file_header->mode);
230 }
231 if (archive_handle->ah_flags & ARCHIVE_RESTORE_DATE) {
232 struct timeval t[2];
233
234 t[1].tv_sec = t[0].tv_sec = file_header->mtime;
235 t[1].tv_usec = t[0].tv_usec = 0;
236 utimes(dst_name, t);
237 }
238 }
239
240 ret: ;
241#if ENABLE_FEATURE_TAR_SELINUX
242 if (sctx) {
243 /* reset the context after creating an entry */
244 setfscreatecon(NULL);
245 }
246#endif
247}
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