1 /* Generate an index to speed access to archives.
2    Copyright (C) 2005-2012 Red Hat, Inc.
3    This file is part of elfutils.
4    Written by Ulrich Drepper <drepper@redhat.com>, 2005.
5 
6    This file is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3 of the License, or
9    (at your option) any later version.
10 
11    elfutils is distributed in the hope that it will be useful, but
12    WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
18 
19 #ifdef HAVE_CONFIG_H
20 # include <config.h>
21 #endif
22 
23 #include <ar.h>
24 #include <argp.h>
25 #include <assert.h>
26 #include <errno.h>
27 #include <error.h>
28 #include <fcntl.h>
29 #include <gelf.h>
30 #include <libintl.h>
31 #include <locale.h>
32 #include <obstack.h>
33 #include <stdlib.h>
34 #include <stdio.h>
35 #include <stdio_ext.h>
36 #include <unistd.h>
37 #include <sys/mman.h>
38 #include <sys/param.h>
39 #include <sys/stat.h>
40 
41 #include <system.h>
42 
43 #include "arlib.h"
44 
45 
46 /* Prototypes for local functions.  */
47 static int handle_file (const char *fname);
48 
49 
50 /* Name and version of program.  */
51 static void print_version (FILE *stream, struct argp_state *state);
52 ARGP_PROGRAM_VERSION_HOOK_DEF = print_version;
53 
54 /* Bug report address.  */
55 ARGP_PROGRAM_BUG_ADDRESS_DEF = PACKAGE_BUGREPORT;
56 
57 
58 /* Definitions of arguments for argp functions.  */
59 static const struct argp_option options[] =
60 {
61   { NULL, 0, NULL, 0, NULL, 0 }
62 };
63 
64 /* Short description of program.  */
65 static const char doc[] = N_("Generate an index to speed access to archives.");
66 
67 /* Strings for arguments in help texts.  */
68 static const char args_doc[] = N_("ARCHIVE");
69 
70 /* Data structure to communicate with argp functions.  */
71 static const struct argp argp =
72 {
73   options, NULL, args_doc, doc, arlib_argp_children, NULL, NULL
74 };
75 
76 
77 int
main(int argc,char * argv[])78 main (int argc, char *argv[])
79 {
80   /* We use no threads here which can interfere with handling a stream.  */
81   (void) __fsetlocking (stdin, FSETLOCKING_BYCALLER);
82   (void) __fsetlocking (stdout, FSETLOCKING_BYCALLER);
83   (void) __fsetlocking (stderr, FSETLOCKING_BYCALLER);
84 
85   /* Set locale.  */
86   (void) setlocale (LC_ALL, "");
87 
88   /* Make sure the message catalog can be found.  */
89   (void) bindtextdomain (PACKAGE_TARNAME, LOCALEDIR);
90 
91   /* Initialize the message catalog.  */
92   (void) textdomain (PACKAGE_TARNAME);
93 
94   /* Parse and process arguments.  */
95   int remaining;
96   (void) argp_parse (&argp, argc, argv, ARGP_IN_ORDER, &remaining, NULL);
97 
98   /* Tell the library which version we are expecting.  */
99   (void) elf_version (EV_CURRENT);
100 
101   /* There must at least be one more parameter specifying the archive.   */
102   if (remaining == argc)
103     {
104       error (0, 0, gettext ("Archive name required"));
105       argp_help (&argp, stderr, ARGP_HELP_SEE, "ranlib");
106       exit (EXIT_FAILURE);
107     }
108 
109   /* We accept the names of multiple archives.  */
110   int status = 0;
111   do
112     status |= handle_file (argv[remaining]);
113   while (++remaining < argc);
114 
115   return status;
116 }
117 
118 
119 /* Print the version information.  */
120 static void
print_version(FILE * stream,struct argp_state * state)121 print_version (FILE *stream, struct argp_state *state __attribute__ ((unused)))
122 {
123   fprintf (stream, "ranlib (%s) %s\n", PACKAGE_NAME, PACKAGE_VERSION);
124   fprintf (stream, gettext ("\
125 Copyright (C) %s Red Hat, Inc.\n\
126 This is free software; see the source for copying conditions.  There is NO\n\
127 warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
128 "), "2012");
129   fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
130 }
131 
132 
133 static int
copy_content(Elf * elf,int newfd,off_t off,size_t n)134 copy_content (Elf *elf, int newfd, off_t off, size_t n)
135 {
136   size_t len;
137   char *rawfile = elf_rawfile (elf, &len);
138 
139   assert (off + n <= len);
140 
141   /* Tell the kernel we will read all the pages sequentially.  */
142   size_t ps = sysconf (_SC_PAGESIZE);
143   if (n > 2 * ps)
144     posix_madvise (rawfile + (off & ~(ps - 1)), n, POSIX_MADV_SEQUENTIAL);
145 
146   return write_retry (newfd, rawfile + off, n) != (ssize_t) n;
147 }
148 
149 
150 /* Handle a file given on the command line.  */
151 static int
handle_file(const char * fname)152 handle_file (const char *fname)
153 {
154   int fd = open (fname, O_RDONLY);
155   if (fd == -1)
156     {
157       error (0, errno, gettext ("cannot open '%s'"), fname);
158       return 1;
159     }
160 
161   struct stat st;
162   if (fstat (fd, &st) != 0)
163     {
164       error (0, errno, gettext ("cannot stat '%s'"), fname);
165       close (fd);
166       return 1;
167     }
168 
169   /* First we walk through the file, looking for all ELF files to
170      collect symbols from.  */
171   Elf *arelf = elf_begin (fd, ELF_C_READ_MMAP, NULL);
172   if (arelf == NULL)
173     {
174       error (0, 0, gettext ("cannot create ELF descriptor for '%s': %s"),
175 	     fname, elf_errmsg (-1));
176       close (fd);
177       return 1;
178     }
179 
180   if (elf_kind (arelf) != ELF_K_AR)
181     {
182       error (0, 0, gettext ("'%s' is no archive"), fname);
183       elf_end (arelf);
184       close (fd);
185       return 1;
186     }
187 
188   arlib_init ();
189 
190   /* Iterate over the content of the archive.  */
191   off_t index_off = -1;
192   size_t index_size = 0;
193   off_t cur_off = SARMAG;
194   Elf *elf;
195   Elf_Cmd cmd = ELF_C_READ_MMAP;
196   while ((elf = elf_begin (fd, cmd, arelf)) != NULL)
197     {
198       Elf_Arhdr *arhdr = elf_getarhdr (elf);
199       assert (arhdr != NULL);
200 
201       /* If this is the index, remember the location.  */
202       if (strcmp (arhdr->ar_name, "/") == 0)
203 	{
204 	  index_off = elf_getaroff (elf);
205 	  index_size = arhdr->ar_size;
206 	}
207       else
208 	{
209 	  arlib_add_symbols (elf, fname, arhdr->ar_name, cur_off);
210 	  cur_off += (((arhdr->ar_size + 1) & ~((off_t) 1))
211 		      + sizeof (struct ar_hdr));
212 	}
213 
214       /* Get next archive element.  */
215       cmd = elf_next (elf);
216       if (elf_end (elf) != 0)
217 	error (0, 0, gettext ("error while freeing sub-ELF descriptor: %s"),
218 	       elf_errmsg (-1));
219     }
220 
221   arlib_finalize ();
222 
223   /* If the file contains no symbols we need not do anything.  */
224   int status = 0;
225   if (symtab.symsnamelen != 0
226       /* We have to rewrite the file also if it initially had an index
227 	 but now does not need one anymore.  */
228       || (symtab.symsnamelen == 0 && index_size != 0))
229     {
230       /* Create a new, temporary file in the same directory as the
231 	 original file.  */
232       char tmpfname[strlen (fname) + 7];
233       strcpy (stpcpy (tmpfname, fname), "XXXXXX");
234       int newfd = mkstemp (tmpfname);
235       if (unlikely (newfd == -1))
236 	{
237 	nonew:
238 	  error (0, errno, gettext ("cannot create new file"));
239 	  status = 1;
240 	}
241       else
242 	{
243 	  /* Create the header.  */
244 	  if (unlikely (write_retry (newfd, ARMAG, SARMAG) != SARMAG))
245 	    {
246 	      // XXX Use /prof/self/fd/%d ???
247 	    nonew_unlink:
248 	      unlink (tmpfname);
249 	      if (newfd != -1)
250 		close (newfd);
251 	      goto nonew;
252 	    }
253 
254 	  /* Create the new file.  There are three parts as far we are
255 	     concerned: 1. original context before the index, 2. the
256 	     new index, 3. everything after the new index.  */
257 	  off_t rest_off;
258 	  if (index_off != -1)
259 	    rest_off = (index_off + sizeof (struct ar_hdr)
260 			+ ((index_size + 1) & ~1ul));
261 	  else
262 	    rest_off = SARMAG;
263 
264 	  if ((symtab.symsnamelen != 0
265 	       && ((write_retry (newfd, symtab.symsoff,
266 				 symtab.symsofflen)
267 		    != (ssize_t) symtab.symsofflen)
268 		   || (write_retry (newfd, symtab.symsname,
269 				    symtab.symsnamelen)
270 		       != (ssize_t) symtab.symsnamelen)))
271 	      /* Even if the original file had content before the
272 		 symbol table, we write it in the correct order.  */
273 	      || (index_off > SARMAG
274 		  && copy_content (arelf, newfd, SARMAG, index_off - SARMAG))
275 	      || copy_content (arelf, newfd, rest_off, st.st_size - rest_off)
276 	      /* Set the mode of the new file to the same values the
277 		 original file has.  */
278 	      || fchmod (newfd, st.st_mode & ALLPERMS) != 0
279 	      /* Never complain about fchown failing.  */
280 	      || (({asm ("" :: "r" (fchown (newfd, st.st_uid, st.st_gid))); }),
281 		  close (newfd) != 0)
282 	      || (newfd = -1, rename (tmpfname, fname) != 0))
283 	    goto nonew_unlink;
284 	}
285     }
286 
287   elf_end (arelf);
288 
289   arlib_fini ();
290 
291   close (fd);
292 
293   return status;
294 }
295 
296 
297 #include "debugpred.h"
298