1 /* vi: set sw=4 ts=4: */
3 * Mini ar implementation for busybox
5 * Copyright (C) 2000 by Glenn McGrath
7 * Based in part on BusyBox tar, Debian dpkg-deb and GNU ar.
9 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
11 * Archive creation support:
12 * Copyright (C) 2010 Nokia Corporation. All rights reserved.
13 * Written by Alexander Shishkin.
15 * There is no single standard to adhere to so ar may not portable
16 * between different systems
17 * http://www.unix-systems.org/single_unix_specification_v2/xcu/ar.html
21 //config: bool "ar (9.5 kb)"
22 //config: default n # needs to be improved to be able to replace binutils ar
24 //config: ar is an archival utility program used to create, modify, and
25 //config: extract contents from archives. In practice, it is used exclusively
26 //config: for object module archives used by compilers.
28 //config: Unless you have a specific application which requires ar, you should
29 //config: probably say N here: most compilers come with their own ar utility.
31 //config:config FEATURE_AR_LONG_FILENAMES
32 //config: bool "Support long filenames (not needed for debs)"
34 //config: depends on AR
36 //config: By default the ar format can only store the first 15 characters
37 //config: of the filename, this option removes that limitation.
38 //config: It supports the GNU ar long filename method which moves multiple long
39 //config: filenames into a the data section of a new ar entry.
41 //config:config FEATURE_AR_CREATE
42 //config: bool "Support archive creation"
44 //config: depends on AR
46 //config: This enables archive creation (-c and -r) with busybox ar.
48 //applet:IF_AR(APPLET(ar, BB_DIR_USR_BIN, BB_SUID_DROP))
49 //kbuild:lib-$(CONFIG_AR) += ar.o
51 //usage:#define ar_trivial_usage
52 //usage: "[-o] [-v] [-p] [-t] [-x] ARCHIVE FILES"
53 //usage:#define ar_full_usage "\n\n"
54 //usage: "Extract or list FILES from an ar archive\n"
55 //usage: "\n -o Preserve original dates"
56 //usage: "\n -p Extract to stdout"
58 //usage: "\n -x Extract"
59 //usage: "\n -v Verbose"
62 #include "bb_archive.h"
65 #if ENABLE_FEATURE_AR_CREATE
66 /* filter out entries with same names as specified on the command line */
67 static char FAST_FUNC filter_replaceable(archive_handle_t *handle)
69 if (find_list_entry(handle->accept, handle->file_header->name))
75 static void output_ar_header(archive_handle_t *handle)
77 /* GNU ar 2.19.51.0.14 creates malformed archives
78 * if input files are >10G. It also truncates files >4GB
79 * (uses "size mod 4G"). We abort in this case:
80 * We could add support for up to 10G files, but this is unlikely to be useful.
81 * Note that unpacking side limits all fields to "unsigned int" data type,
82 * and treats "all ones" as an error indicator. Thus max we allow here is UINT_MAX-1.
85 /* for 2nd field: mtime */
86 MAX11CHARS = UINT_MAX > 0xffffffff ? (unsigned)99999999999 : UINT_MAX-1,
87 /* for last field: filesize */
88 MAX10CHARS = UINT_MAX > 0xffffffff ? (unsigned)9999999999 : UINT_MAX-1,
91 struct file_header_t *fh = handle->file_header;
93 if (handle->offset & 1) {
94 xwrite(handle->src_fd, "\n", 1);
98 /* Careful! The widths should be exact. Fields must be separated */
99 if (sizeof(off_t) > 4 && fh->size > (off_t)MAX10CHARS) {
100 bb_error_msg_and_die("'%s' is bigger than ar can handle", fh->name);
102 fdprintf(handle->src_fd, "%-16.16s%-12lu%-6u%-6u%-8o%-10"OFF_FMT"u`\n",
104 (sizeof(time_t) > 4 && fh->mtime > MAX11CHARS) ? (long)0 : (long)fh->mtime,
105 fh->uid > 99999 ? 0 : (int)fh->uid,
106 fh->gid > 99999 ? 0 : (int)fh->gid,
107 (int)fh->mode & 07777777,
111 handle->offset += AR_HEADER_LEN;
115 * when replacing files in an existing archive, copy from the
116 * original archive those files that are to be left intact
118 static void FAST_FUNC copy_data(archive_handle_t *handle)
120 archive_handle_t *out_handle = handle->ar__out;
121 struct file_header_t *fh = handle->file_header;
123 out_handle->file_header = fh;
124 output_ar_header(out_handle);
126 bb_copyfd_exact_size(handle->src_fd, out_handle->src_fd, fh->size);
127 out_handle->offset += fh->size;
130 static int write_ar_header(archive_handle_t *handle)
133 char fn_h[17]; /* 15 + "/" + NUL */
137 fn = llist_pop(&handle->accept);
143 handle->file_header->mtime = st.st_mtime;
144 handle->file_header->uid = st.st_uid;
145 handle->file_header->gid = st.st_gid;
146 handle->file_header->mode = st.st_mode;
147 handle->file_header->size = st.st_size;
148 handle->file_header->name = fn_h;
149 //TODO: if ENABLE_FEATURE_AR_LONG_FILENAMES...
150 sprintf(fn_h, "%.15s/", bb_basename(fn));
152 output_ar_header(handle);
154 fd = xopen(fn, O_RDONLY);
155 bb_copyfd_exact_size(fd, handle->src_fd, st.st_size);
157 handle->offset += st.st_size;
162 static int write_ar_archive(archive_handle_t *handle)
165 archive_handle_t *out_handle;
167 xfstat(handle->src_fd, &st, handle->ar__name);
169 /* if archive exists, create a new handle for output.
170 * we create it in place of the old one.
172 if (st.st_size != 0) {
173 out_handle = init_handle();
174 xunlink(handle->ar__name);
175 out_handle->src_fd = xopen(handle->ar__name, O_WRONLY | O_CREAT | O_TRUNC);
176 out_handle->accept = handle->accept;
181 handle->ar__out = out_handle;
183 xwrite(out_handle->src_fd, AR_MAGIC "\n", AR_MAGIC_LEN + 1);
184 out_handle->offset += AR_MAGIC_LEN + 1;
186 /* skip to the end of the archive if we have to append stuff */
187 if (st.st_size != 0) {
188 handle->filter = filter_replaceable;
189 handle->action_data = copy_data;
190 unpack_ar_archive(handle);
193 while (write_ar_header(out_handle) == 0)
196 /* optional, since we exit right after we return */
197 if (ENABLE_FEATURE_CLEAN_UP) {
198 close(handle->src_fd);
199 if (out_handle->src_fd != handle->src_fd)
200 close(out_handle->src_fd);
205 #endif /* FEATURE_AR_CREATE */
207 static void FAST_FUNC header_verbose_list_ar(const file_header_t *file_header)
209 const char *mode = bb_mode_string(file_header->mode);
212 mtime = ctime(&file_header->mtime);
214 memmove(&mtime[17], &mtime[20], 4);
216 printf("%s %u/%u%7"OFF_FMT"u %s %s\n", &mode[1],
217 (int)file_header->uid, (int)file_header->gid,
219 &mtime[4], file_header->name
223 #define AR_OPT_VERBOSE (1 << 0)
224 #define AR_OPT_PRESERVE_DATE (1 << 1)
225 /* "ar r" implies create, but warns about it. c suppresses warning.
226 * bbox accepts but ignores it: */
227 #define AR_OPT_CREATE (1 << 2)
229 #define AR_CMD_PRINT (1 << 3)
230 #define FIRST_CMD AR_CMD_PRINT
231 #define AR_CMD_LIST (1 << 4)
232 #define AR_CMD_EXTRACT (1 << 5)
233 #define AR_CMD_INSERT (1 << 6)
235 int ar_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
236 int ar_main(int argc UNUSED_PARAM, char **argv)
238 archive_handle_t *archive_handle;
241 archive_handle = init_handle();
243 /* --: prepend '-' to the first argument if required */
244 /* -1: at least one param is reqd */
245 /* one of p,t,x[,r] is required */
246 opt_complementary = "--:-1:p:t:x"IF_FEATURE_AR_CREATE(":r");
247 opt = getopt32(argv, "voc""ptx"IF_FEATURE_AR_CREATE("r"));
251 if (t & (t-1)) /* more than one of p,t,x[,r] are specified */
254 if (opt & AR_CMD_PRINT) {
255 archive_handle->action_data = data_extract_to_stdout;
257 if (opt & AR_CMD_LIST) {
258 archive_handle->action_header = header_list;
260 if (opt & AR_CMD_EXTRACT) {
261 archive_handle->action_data = data_extract_all;
263 if (opt & AR_OPT_PRESERVE_DATE) {
264 archive_handle->ah_flags |= ARCHIVE_RESTORE_DATE;
266 if (opt & AR_OPT_VERBOSE) {
267 archive_handle->action_header = header_verbose_list_ar;
269 #if ENABLE_FEATURE_AR_CREATE
270 archive_handle->ar__name = *argv;
272 archive_handle->src_fd = xopen(*argv++,
273 (opt & AR_CMD_INSERT)
279 archive_handle->filter = filter_accept_list;
281 llist_add_to_end(&archive_handle->accept, *argv++);
284 #if ENABLE_FEATURE_AR_CREATE
285 if (opt & AR_CMD_INSERT)
286 return write_ar_archive(archive_handle);
289 unpack_ar_archive(archive_handle);