usr.bin/ar/write.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2007 Kai Wang
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer
  12  *    in this position and unchanged.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include <sys/cdefs.h>
  30 __FBSDID("$FreeBSD$");
  31
  32 #include <sys/endian.h>
  33 #include <sys/mman.h>
  34 #include <sys/queue.h>
  35 #include <sys/stat.h>
  36 #include <archive.h>
  37 #include <archive_entry.h>
  38 #include <errno.h>
  39 #include <fcntl.h>
  40 #include <gelf.h>
  41 #include <libgen.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <sysexits.h>
  46 #include <unistd.h>
  47
  48 #include "ar.h"
  49
  50 #define _ARMAG_LEN 8            /* length of ar magic string */
  51 #define _ARHDR_LEN 60           /* length of ar header */
  52 #define _INIT_AS_CAP 128        /* initial archive string table size */
  53 #define _INIT_SYMOFF_CAP (256*(sizeof(uint32_t))) /* initial so table size */
  54 #define _INIT_SYMNAME_CAP 1024                    /* initial sn table size */
  55 #define _MAXNAMELEN_SVR4 15     /* max member name length in svr4 variant */
  56 #define _TRUNCATE_LEN 15        /* number of bytes to keep for member name */
  57
  58 static void     add_to_ar_str_table(struct bsdar *bsdar, const char *name);
  59 static void     add_to_ar_sym_table(struct bsdar *bsdar, const char *name);
  60 static struct ar_obj    *create_obj_from_file(struct bsdar *bsdar,
  61                     const char *name, time_t mtime);
  62 static void     create_symtab_entry(struct bsdar *bsdar, void *maddr,
  63                     size_t size);
  64 static void     free_obj(struct bsdar *bsdar, struct ar_obj *obj);
  65 static void     insert_obj(struct bsdar *bsdar, struct ar_obj *obj,
  66                     struct ar_obj *pos);
  67 static void     prefault_buffer(const char *buf, size_t s);
  68 static void     read_objs(struct bsdar *bsdar, const char *archive,
  69                     int checkargv);
  70 static void     write_archive(struct bsdar *bsdar, char mode);
  71 static void     write_cleanup(struct bsdar *bsdar);
  72 static void     write_data(struct bsdar *bsdar, struct archive *a,
  73                     const void *buf, size_t s);
  74 static void     write_objs(struct bsdar *bsdar);
  75
  76 void
  77 ar_mode_d(struct bsdar *bsdar)
  78 {
  79
  80         write_archive(bsdar, 'd');
  81 }
  82
  83 void
  84 ar_mode_m(struct bsdar *bsdar)
  85 {
  86
  87         write_archive(bsdar, 'm');
  88 }
  89
  90 void
  91 ar_mode_q(struct bsdar *bsdar)
  92 {
  93
  94         write_archive(bsdar, 'q');
  95 }
  96
  97 void
  98 ar_mode_r(struct bsdar *bsdar)
  99 {
 100
 101         write_archive(bsdar, 'r');
 102 }
 103
 104 void
 105 ar_mode_s(struct bsdar *bsdar)
 106 {
 107
 108         write_archive(bsdar, 's');
 109 }
 110
 111 void
 112 ar_mode_A(struct bsdar *bsdar)
 113 {
 114
 115         write_archive(bsdar, 'A');
 116 }
 117
 118 /*
 119  * Create object from file, return created obj upon success, or NULL
 120  * when an error occurs or the member is not newer than existing
 121  * one while -u is specified.
 122  */
 123 static struct ar_obj *
 124 create_obj_from_file(struct bsdar *bsdar, const char *name, time_t mtime)
 125 {
 126         struct ar_obj           *obj;
 127         struct stat              sb;
 128         const char              *bname;
 129         char                    *tmpname;
 130
 131         if (name == NULL)
 132                 return (NULL);
 133
 134         obj = malloc(sizeof(struct ar_obj));
 135         if (obj == NULL)
 136                 bsdar_errc(bsdar, EX_SOFTWARE, errno, "malloc failed");
 137         if ((obj->fd = open(name, O_RDONLY, 0)) < 0) {
 138                 bsdar_warnc(bsdar, errno, "can't open file: %s", name);
 139                 free(obj);
 140                 return (NULL);
 141         }
 142
 143         tmpname = strdup(name);
 144         if (tmpname == NULL)
 145                 bsdar_errc(bsdar, EX_SOFTWARE, errno, "strdup failed");
 146         if ((bname = basename(tmpname)) == NULL)
 147                 bsdar_errc(bsdar, EX_SOFTWARE, errno, "basename failed");
 148         if (bsdar->options & AR_TR && strlen(bname) > _TRUNCATE_LEN) {
 149                 if ((obj->name = malloc(_TRUNCATE_LEN + 1)) == NULL)
 150                         bsdar_errc(bsdar, EX_SOFTWARE, errno, "malloc failed");
 151                 (void)strncpy(obj->name, bname, _TRUNCATE_LEN);
 152                 obj->name[_TRUNCATE_LEN] = '\0';
 153         } else
 154                 if ((obj->name = strdup(bname)) == NULL)
 155                     bsdar_errc(bsdar, EX_SOFTWARE, errno, "strdup failed");
 156         free(tmpname);
 157
 158         if (fstat(obj->fd, &sb) < 0) {
 159                 bsdar_warnc(bsdar, errno, "can't fstat file: %s", obj->name);
 160                 goto giveup;
 161         }
 162         if (!S_ISREG(sb.st_mode)) {
 163                 bsdar_warnc(bsdar, 0, "%s is not an ordinary file", obj->name);
 164                 goto giveup;
 165         }
 166
 167         /*
 168          * When option '-u' is specified and member is not newer than the
 169          * existing one, the replace will not happen. While if mtime == 0,
 170          * which indicates that this is to "replace a none exist member",
 171          * the replace will proceed regardless of '-u'.
 172          */
 173         if (mtime != 0 && bsdar->options & AR_U && sb.st_mtime <= mtime)
 174                 goto giveup;
 175
 176         /*
 177          * When option '-D' is specified, mtime and UID / GID from the file
 178          * will be replaced with 0, and file mode with 644. This ensures that
 179          * checksums will match for two archives containing the exact same
 180          * files.
 181          */
 182         if (bsdar->options & AR_D) {
 183                 obj->uid = 0;
 184                 obj->gid = 0;
 185                 obj->mtime = 0;
 186                 obj->md = S_IFREG | 0644;
 187         } else {
 188                 obj->uid = sb.st_uid;
 189                 obj->gid = sb.st_gid;
 190                 obj->mtime = sb.st_mtime;
 191                 obj->md = sb.st_mode;
 192         }
 193         obj->size = sb.st_size;
 194         obj->dev = sb.st_dev;
 195         obj->ino = sb.st_ino;
 196
 197         if (obj->size == 0) {
 198                 obj->maddr = NULL;
 199                 return (obj);
 200         }
 201
 202         if ((obj->maddr = mmap(NULL, obj->size, PROT_READ,
 203             MAP_PRIVATE, obj->fd, (off_t)0)) == MAP_FAILED) {
 204                 bsdar_warnc(bsdar, errno, "can't mmap file: %s", obj->name);
 205                 goto giveup;
 206         }
 207         if (close(obj->fd) < 0)
 208                 bsdar_errc(bsdar, EX_SOFTWARE, errno, "close failed: %s",
 209                     obj->name);
 210
 211         return (obj);
 212
 213 giveup:
 214         if (close(obj->fd) < 0)
 215                 bsdar_errc(bsdar, EX_SOFTWARE, errno, "close failed: %s",
 216                     obj->name);
 217         free(obj->name);
 218         free(obj);
 219         return (NULL);
 220 }
 221
 222 /*
 223  * Free object itself and its associated allocations.
 224  */
 225 static void
 226 free_obj(struct bsdar *bsdar, struct ar_obj *obj)
 227 {
 228         if (obj->fd == -1)
 229                 free(obj->maddr);
 230         else
 231                 if (obj->maddr != NULL && munmap(obj->maddr, obj->size))
 232                         bsdar_warnc(bsdar, errno,
 233                             "can't munmap file: %s", obj->name);
 234         free(obj->name);
 235         free(obj);
 236 }
 237
 238 /*
 239  * Insert obj to the tail, or before/after the pos obj.
 240  */
 241 static void
 242 insert_obj(struct bsdar *bsdar, struct ar_obj *obj, struct ar_obj *pos)
 243 {
 244         if (obj == NULL)
 245                 bsdar_errc(bsdar, EX_SOFTWARE, 0, "try to insert a null obj");
 246
 247         if (pos == NULL || obj == pos)
 248                 /*
 249                  * If the object to move happens to be the position obj,
 250                  * or if there is not a pos obj, move it to tail.
 251                  */
 252                 goto tail;
 253
 254         if (bsdar->options & AR_B) {
 255                 TAILQ_INSERT_BEFORE(pos, obj, objs);
 256                 return;
 257         }
 258         if (bsdar->options & AR_A) {
 259                 TAILQ_INSERT_AFTER(&bsdar->v_obj, pos, obj, objs);
 260                 return;
 261         }
 262
 263 tail:
 264         TAILQ_INSERT_TAIL(&bsdar->v_obj, obj, objs);
 265
 266 }
 267
 268 /*
 269  * Read objects from archive into v_obj list. Note that checkargv is
 270  * set when read_objs is used to read objects from the target of
 271  * ADDLIB command (ar script mode), in this case argv array possibly
 272  * specifies the members ADDLIB want.
 273  */
 274 static void
 275 read_objs(struct bsdar *bsdar, const char *archive, int checkargv)
 276 {
 277         struct archive           *a;
 278         struct archive_entry     *entry;
 279         struct ar_obj            *obj;
 280         const char               *name;
 281         const char               *bname;
 282         char                     *buff;
 283         char                    **av;
 284         size_t                    size;
 285         int                       i, r, find;
 286
 287         if ((a = archive_read_new()) == NULL)
 288                 bsdar_errc(bsdar, EX_SOFTWARE, 0, "archive_read_new failed");
 289         archive_read_support_format_ar(a);
 290         AC(archive_read_open_filename(a, archive, DEF_BLKSZ));
 291         for (;;) {
 292                 r = archive_read_next_header(a, &entry);
 293                 if (r == ARCHIVE_FATAL)
 294                         bsdar_errc(bsdar, EX_DATAERR, 0, "%s",
 295                             archive_error_string(a));
 296                 if (r == ARCHIVE_EOF)
 297                         break;
 298                 if (r == ARCHIVE_WARN || r == ARCHIVE_RETRY)
 299                         bsdar_warnc(bsdar, 0, "%s", archive_error_string(a));
 300                 if (r == ARCHIVE_RETRY) {
 301                         bsdar_warnc(bsdar, 0, "Retrying...");
 302                         continue;
 303                 }
 304
 305                 name = archive_entry_pathname(entry);
 306
 307                 /*
 308                  * skip pseudo members.
 309                  */
 310                 if (strcmp(name, "/") == 0 || strcmp(name, "//") == 0)
 311                         continue;
 312
 313                 /*
 314                  * If checkargv is set, only read those members specified
 315                  * in argv.
 316                  */
 317                 if (checkargv && bsdar->argc > 0) {
 318                         find = 0;
 319                         for(i = 0; i < bsdar->argc; i++) {
 320                                 av = &bsdar->argv[i];
 321                                 if (*av == NULL)
 322                                         continue;
 323                                 if ((bname = basename(*av)) == NULL)
 324                                         bsdar_errc(bsdar, EX_SOFTWARE, errno,
 325                                             "basename failed");
 326                                 if (strcmp(bname, name) != 0)
 327                                         continue;
 328
 329                                 *av = NULL;
 330                                 find = 1;
 331                                 break;
 332                         }
 333                         if (!find)
 334                                 continue;
 335                 }
 336
 337                 size = archive_entry_size(entry);
 338
 339                 if (size > 0) {
 340                         if ((buff = malloc(size)) == NULL)
 341                                 bsdar_errc(bsdar, EX_SOFTWARE, errno,
 342                                     "malloc failed");
 343                         if (archive_read_data(a, buff, size) != (ssize_t)size) {
 344                                 bsdar_warnc(bsdar, 0, "%s",
 345                                     archive_error_string(a));
 346                                 free(buff);
 347                                 continue;
 348                         }
 349                 } else
 350                         buff = NULL;
 351
 352                 obj = malloc(sizeof(struct ar_obj));
 353                 if (obj == NULL)
 354                         bsdar_errc(bsdar, EX_SOFTWARE, errno, "malloc failed");
 355                 obj->maddr = buff;
 356                 if ((obj->name = strdup(name)) == NULL)
 357                         bsdar_errc(bsdar, EX_SOFTWARE, errno, "strdup failed");
 358                 obj->size = size;
 359                 obj->uid = archive_entry_uid(entry);
 360                 obj->gid = archive_entry_gid(entry);
 361                 obj->md = archive_entry_mode(entry);
 362                 obj->mtime = archive_entry_mtime(entry);
 363                 obj->dev = 0;
 364                 obj->ino = 0;
 365
 366                 /*
 367                  * Objects from archive have obj->fd set to -1,
 368                  * for the ease of cleaning up.
 369                  */
 370                 obj->fd = -1;
 371                 TAILQ_INSERT_TAIL(&bsdar->v_obj, obj, objs);
 372         }
 373         AC(archive_read_close(a));
 374         AC(archive_read_free(a));
 375 }
 376
 377 /*
 378  * Determine the constitution of resulting archive.
 379  */
 380 static void
 381 write_archive(struct bsdar *bsdar, char mode)
 382 {
 383         struct ar_obj            *nobj, *obj, *obj_temp, *pos;
 384         struct stat               sb;
 385         const char               *bname;
 386         char                    **av;
 387         int                       i;
 388
 389         TAILQ_INIT(&bsdar->v_obj);
 390         nobj = NULL;
 391         pos = NULL;
 392         memset(&sb, 0, sizeof(sb));
 393
 394         /*
 395          * Test if the specified archive exists, to figure out
 396          * whether we are creating one here.
 397          */
 398         if (stat(bsdar->filename, &sb) != 0) {
 399                 if (errno != ENOENT) {
 400                         bsdar_warnc(bsdar, 0, "stat %s failed",
 401                             bsdar->filename);
 402                         return;
 403                 }
 404
 405                 /* We do not create archive in mode 'd', 'm' and 's'.  */
 406                 if (mode != 'r' && mode != 'q') {
 407                         bsdar_warnc(bsdar, 0, "%s: no such file",
 408                             bsdar->filename);
 409                         return;
 410                 }
 411
 412                 /* Issue a warning if -c is not specified when creating. */
 413                 if (!(bsdar->options & AR_C))
 414                         bsdar_warnc(bsdar, 0, "creating %s", bsdar->filename);
 415                 goto new_archive;
 416         }
 417
 418         /*
 419          * First read members from existing archive.
 420          */
 421         read_objs(bsdar, bsdar->filename, 0);
 422
 423         /*
 424          * For mode 's', no member will be moved, deleted or replaced.
 425          */
 426         if (mode == 's')
 427                 goto write_objs;
 428
 429         /*
 430          * For mode 'q', we don't need to adjust existing members either.
 431          * Also, -a, -b and -i are ignored in this mode. New members are
 432          * always inserted at tail.
 433          */
 434         if (mode == 'q')
 435                 goto new_archive;
 436
 437         /*
 438          * Mode 'A' adds the contents of another archive to the tail of
 439          * current archive. Note that mode 'A' is a special mode for the
 440          * ADDLIB command of the ar script mode. Currently there is no
 441          * access to this function from the ar command line mode.
 442          */
 443         if (mode == 'A') {
 444                 /*
 445                  * Read objects from the target archive of ADDLIB command.
 446                  * If there are members specified in argv, read those members
 447                  * only, otherwise the entire archive will be read.
 448                  */
 449                 read_objs(bsdar, bsdar->addlib, 1);
 450                 goto write_objs;
 451         }
 452
 453         /*
 454          * Try to find the position member specified by user.
 455          */
 456         if (bsdar->options & AR_A || bsdar->options & AR_B) {
 457                 TAILQ_FOREACH(obj, &bsdar->v_obj, objs) {
 458                         if (strcmp(obj->name, bsdar->posarg) == 0) {
 459                                 pos = obj;
 460                                 break;
 461                         }
 462                 }
 463
 464                 /*
 465                  * If can't find `pos' specified by user,
 466                  * silently insert objects at tail.
 467                  */
 468                 if (pos == NULL)
 469                         bsdar->options &= ~(AR_A | AR_B);
 470         }
 471
 472         for (i = 0; i < bsdar->argc; i++) {
 473                 av = &bsdar->argv[i];
 474
 475                 TAILQ_FOREACH_SAFE(obj, &bsdar->v_obj, objs, obj_temp) {
 476                         if ((bname = basename(*av)) == NULL)
 477                                 bsdar_errc(bsdar, EX_SOFTWARE, errno,
 478                                     "basename failed");
 479                         if (bsdar->options & AR_TR) {
 480                                 if (strncmp(bname, obj->name, _TRUNCATE_LEN))
 481                                         continue;
 482                         } else
 483                                 if (strcmp(bname, obj->name) != 0)
 484                                         continue;
 485
 486                         if (mode == 'r') {
 487                                 /*
 488                                  * if the new member is not qualified
 489                                  * to replace the old one, skip it.
 490                                  */
 491                                 nobj = create_obj_from_file(bsdar, *av,
 492                                     obj->mtime);
 493                                 if (nobj == NULL)
 494                                         goto skip_obj;
 495                         }
 496
 497                         if (bsdar->options & AR_V)
 498                                 (void)fprintf(stdout, "%c - %s\n", mode,
 499                                     *av);
 500
 501                         TAILQ_REMOVE(&bsdar->v_obj, obj, objs);
 502                         if (mode == 'd' || mode == 'r')
 503                                 free_obj(bsdar, obj);
 504
 505                         if (mode == 'm')
 506                                 insert_obj(bsdar, obj, pos);
 507                         if (mode == 'r')
 508                                 insert_obj(bsdar, nobj, pos);
 509
 510                 skip_obj:
 511                         *av = NULL;
 512                         break;
 513                 }
 514
 515         }
 516
 517 new_archive:
 518         /*
 519          * When operating in mode 'r', directly add those user specified
 520          * objects which do not exist in current archive. When operating
 521          * in mode 'q', all objects specified in command line args are
 522          * appended to the archive, without comparing with existing ones.
 523          */
 524         for (i = 0; i < bsdar->argc; i++) {
 525                 av = &bsdar->argv[i];
 526                 if (*av != NULL && (mode == 'r' || mode == 'q')) {
 527                         nobj = create_obj_from_file(bsdar, *av, 0);
 528                         if (nobj != NULL)
 529                                 insert_obj(bsdar, nobj, pos);
 530                         if (bsdar->options & AR_V && nobj != NULL)
 531                                 (void)fprintf(stdout, "a - %s\n", *av);
 532                         *av = NULL;
 533                 }
 534         }
 535
 536 write_objs:
 537         write_objs(bsdar);
 538         write_cleanup(bsdar);
 539 }
 540
 541 /*
 542  * Memory cleaning up.
 543  */
 544 static void
 545 write_cleanup(struct bsdar *bsdar)
 546 {
 547         struct ar_obj           *obj, *obj_temp;
 548
 549         TAILQ_FOREACH_SAFE(obj, &bsdar->v_obj, objs, obj_temp) {
 550                 TAILQ_REMOVE(&bsdar->v_obj, obj, objs);
 551                 free_obj(bsdar, obj);
 552         }
 553
 554         free(bsdar->as);
 555         free(bsdar->s_so);
 556         free(bsdar->s_sn);
 557         bsdar->as = NULL;
 558         bsdar->s_so = NULL;
 559         bsdar->s_sn = NULL;
 560 }
 561
 562 /*
 563  * Fault in the buffer prior to writing as a workaround for poor performance
 564  * due to interaction with kernel fs deadlock avoidance code. See the comment
 565  * above vn_io_fault_doio() in sys/kern/vfs_vnops.c for details of the issue.
 566  */
 567 static void
 568 prefault_buffer(const char *buf, size_t s)
 569 {
 570         volatile const char *p;
 571         size_t page_size;
 572
 573         if (s == 0)
 574                 return;
 575         page_size = sysconf(_SC_PAGESIZE);
 576         for (p = buf; p < buf + s; p += page_size)
 577                 *p;
 578         /*
 579          * Ensure we touch the last page as well, in case the buffer is not
 580          * page-aligned.
 581          */
 582         *(volatile const char *)(buf + s - 1);
 583 }
 584
 585 /*
 586  * Wrapper for archive_write_data().
 587  */
 588 static void
 589 write_data(struct bsdar *bsdar, struct archive *a, const void *buf, size_t s)
 590 {
 591         ssize_t written;
 592
 593         prefault_buffer(buf, s);
 594         while (s > 0) {
 595                 written = archive_write_data(a, buf, s);
 596                 if (written < 0)
 597                         bsdar_errc(bsdar, EX_SOFTWARE, 0, "%s",
 598                             archive_error_string(a));
 599                 buf = (const char *)buf + written;
 600                 s -= written;
 601         }
 602 }
 603
 604 /*
 605  * Write the resulting archive members.
 606  */
 607 static void
 608 write_objs(struct bsdar *bsdar)
 609 {
 610         struct ar_obj           *obj;
 611         struct archive          *a;
 612         struct archive_entry    *entry;
 613         size_t s_sz;            /* size of archive symbol table. */
 614         size_t pm_sz;           /* size of pseudo members */
 615         int                      i, nr;
 616
 617         if (elf_version(EV_CURRENT) == EV_NONE)
 618                 bsdar_errc(bsdar, EX_SOFTWARE, 0,
 619                     "ELF library initialization failed: %s", elf_errmsg(-1));
 620
 621         bsdar->rela_off = 0;
 622
 623         /* Create archive symbol table and archive string table, if need. */
 624         TAILQ_FOREACH(obj, &bsdar->v_obj, objs) {
 625                 if (!(bsdar->options & AR_SS) && obj->maddr != NULL)
 626                         create_symtab_entry(bsdar, obj->maddr, obj->size);
 627                 if (strlen(obj->name) > _MAXNAMELEN_SVR4)
 628                         add_to_ar_str_table(bsdar, obj->name);
 629                 bsdar->rela_off += _ARHDR_LEN + obj->size + obj->size % 2;
 630                 if (bsdar->rela_off > UINT32_MAX)
 631                         bsdar_errc(bsdar, EX_SOFTWARE, 0,
 632                             "Symbol table offset overflow");
 633         }
 634
 635         /*
 636          * Pad the symbol name string table. It is treated specially because
 637          * symbol name table should be padded by a '\0', not the common '\n'
 638          * for other members. The size of sn table includes the pad bit.
 639          */
 640         if (bsdar->s_cnt != 0 && bsdar->s_sn_sz % 2 != 0)
 641                 bsdar->s_sn[bsdar->s_sn_sz++] = '\0';
 642
 643         /*
 644          * Archive string table is padded by a "\n" as the normal members.
 645          * The difference is that the size of archive string table counts
 646          * in the pad bit, while normal members' size fileds do not.
 647          */
 648         if (bsdar->as != NULL && bsdar->as_sz % 2 != 0)
 649                 bsdar->as[bsdar->as_sz++] = '\n';
 650
 651         /*
 652          * If there is a symbol table, calculate the size of pseudo members,
 653          * convert previously stored relative offsets to absolute ones, and
 654          * then make them Big Endian.
 655          *
 656          * absolute_offset = htobe32(relative_offset + size_of_pseudo_members)
 657          */
 658
 659         if (bsdar->s_cnt != 0) {
 660                 s_sz = (bsdar->s_cnt + 1) * sizeof(uint32_t) + bsdar->s_sn_sz;
 661                 pm_sz = _ARMAG_LEN + (_ARHDR_LEN + s_sz);
 662                 if (bsdar->as != NULL)
 663                         pm_sz += _ARHDR_LEN + bsdar->as_sz;
 664                 for (i = 0; (size_t)i < bsdar->s_cnt; i++) {
 665                         if (*(bsdar->s_so + i) > UINT32_MAX - pm_sz)
 666                                 bsdar_errc(bsdar, EX_SOFTWARE, 0,
 667                                     "Symbol table offset overflow");
 668                         *(bsdar->s_so + i) = htobe32(*(bsdar->s_so + i) +
 669                             pm_sz);
 670                 }
 671         }
 672
 673         if ((a = archive_write_new()) == NULL)
 674                 bsdar_errc(bsdar, EX_SOFTWARE, 0, "archive_write_new failed");
 675
 676         archive_write_set_format_ar_svr4(a);
 677
 678         AC(archive_write_open_filename(a, bsdar->filename));
 679
 680         /*
 681          * write the archive symbol table, if there is one.
 682          * If options -s is explicitly specified or we are invoked
 683          * as ranlib, write the symbol table even if it is empty.
 684          */
 685         if ((bsdar->s_cnt != 0 && !(bsdar->options & AR_SS)) ||
 686             bsdar->options & AR_S) {
 687                 entry = archive_entry_new();
 688                 if (entry == NULL)
 689                         bsdar_errc(bsdar, EX_SOFTWARE, 0,
 690                             "archive_entry_new failed");
 691                 archive_entry_copy_pathname(entry, "/");
 692                 if ((bsdar->options & AR_D) == 0)
 693                         archive_entry_set_mtime(entry, time(NULL), 0);
 694                 archive_entry_set_size(entry, (bsdar->s_cnt + 1) *
 695                     sizeof(uint32_t) + bsdar->s_sn_sz);
 696                 AC(archive_write_header(a, entry));
 697                 nr = htobe32(bsdar->s_cnt);
 698                 write_data(bsdar, a, &nr, sizeof(uint32_t));
 699                 write_data(bsdar, a, bsdar->s_so, sizeof(uint32_t) *
 700                     bsdar->s_cnt);
 701                 write_data(bsdar, a, bsdar->s_sn, bsdar->s_sn_sz);
 702                 archive_entry_free(entry);
 703         }
 704
 705         /* write the archive string table, if any. */
 706         if (bsdar->as != NULL) {
 707                 entry = archive_entry_new();
 708                 if (entry == NULL)
 709                         bsdar_errc(bsdar, EX_SOFTWARE, 0,
 710                             "archive_entry_new failed");
 711                 archive_entry_copy_pathname(entry, "//");
 712                 archive_entry_set_size(entry, bsdar->as_sz);
 713                 AC(archive_write_header(a, entry));
 714                 write_data(bsdar, a, bsdar->as, bsdar->as_sz);
 715                 archive_entry_free(entry);
 716         }
 717
 718         /* write normal members. */
 719         TAILQ_FOREACH(obj, &bsdar->v_obj, objs) {
 720                 entry = archive_entry_new();
 721                 if (entry == NULL)
 722                         bsdar_errc(bsdar, EX_SOFTWARE, 0,
 723                             "archive_entry_new failed");
 724                 archive_entry_copy_pathname(entry, obj->name);
 725                 archive_entry_set_uid(entry, obj->uid);
 726                 archive_entry_set_gid(entry, obj->gid);
 727                 archive_entry_set_mode(entry, obj->md);
 728                 archive_entry_set_size(entry, obj->size);
 729                 archive_entry_set_mtime(entry, obj->mtime, 0);
 730                 archive_entry_set_dev(entry, obj->dev);
 731                 archive_entry_set_ino(entry, obj->ino);
 732                 archive_entry_set_filetype(entry, AE_IFREG);
 733                 AC(archive_write_header(a, entry));
 734                 write_data(bsdar, a, obj->maddr, obj->size);
 735                 archive_entry_free(entry);
 736         }
 737
 738         AC(archive_write_close(a));
 739         AC(archive_write_free(a));
 740 }
 741
 742 /*
 743  * Extract global symbols from ELF binary members.
 744  */
 745 static void
 746 create_symtab_entry(struct bsdar *bsdar, void *maddr, size_t size)
 747 {
 748         Elf             *e;
 749         Elf_Scn         *scn;
 750         GElf_Shdr        shdr;
 751         GElf_Sym         sym;
 752         Elf_Data        *data;
 753         char            *name;
 754         size_t           n, shstrndx;
 755         int              elferr, tabndx, len, i;
 756
 757         if ((e = elf_memory(maddr, size)) == NULL) {
 758                 bsdar_warnc(bsdar, 0, "elf_memory() failed: %s",
 759                      elf_errmsg(-1));
 760                 return;
 761         }
 762         if (elf_kind(e) != ELF_K_ELF) {
 763                 /* Silently ignore non-elf member. */
 764                 elf_end(e);
 765                 return;
 766         }
 767         if (elf_getshstrndx(e, &shstrndx) == 0) {
 768                 bsdar_warnc(bsdar, EX_SOFTWARE, 0, "elf_getshstrndx failed: %s",
 769                      elf_errmsg(-1));
 770                 elf_end(e);
 771                 return;
 772         }
 773
 774         tabndx = -1;
 775         scn = NULL;
 776         while ((scn = elf_nextscn(e, scn)) != NULL) {
 777                 if (gelf_getshdr(scn, &shdr) != &shdr) {
 778                         bsdar_warnc(bsdar, 0,
 779                             "elf_getshdr failed: %s", elf_errmsg(-1));
 780                         continue;
 781                 }
 782                 if ((name = elf_strptr(e, shstrndx, shdr.sh_name)) == NULL) {
 783                         bsdar_warnc(bsdar, 0,
 784                             "elf_strptr failed: %s", elf_errmsg(-1));
 785                         continue;
 786                 }
 787                 if (strcmp(name, ".strtab") == 0) {
 788                         tabndx = elf_ndxscn(scn);
 789                         break;
 790                 }
 791         }
 792         elferr = elf_errno();
 793         if (elferr != 0)
 794                 bsdar_warnc(bsdar, 0, "elf_nextscn failed: %s",
 795                      elf_errmsg(elferr));
 796         if (tabndx == -1) {
 797                 bsdar_warnc(bsdar, 0, "can't find .strtab section");
 798                 elf_end(e);
 799                 return;
 800         }
 801
 802         scn = NULL;
 803         while ((scn = elf_nextscn(e, scn)) != NULL) {
 804                 if (gelf_getshdr(scn, &shdr) != &shdr) {
 805                         bsdar_warnc(bsdar, EX_SOFTWARE, 0,
 806                             "elf_getshdr failed: %s", elf_errmsg(-1));
 807                         continue;
 808                 }
 809                 if (shdr.sh_type != SHT_SYMTAB)
 810                         continue;
 811
 812                 data = NULL;
 813                 n = 0;
 814                 while (n < shdr.sh_size &&
 815                     (data = elf_getdata(scn, data)) != NULL) {
 816                         len = data->d_size / shdr.sh_entsize;
 817                         for (i = 0; i < len; i++) {
 818                                 if (gelf_getsym(data, i, &sym) != &sym) {
 819                                         bsdar_warnc(bsdar, EX_SOFTWARE, 0,
 820                                             "gelf_getsym failed: %s",
 821                                              elf_errmsg(-1));
 822                                         continue;
 823                                 }
 824
 825                                 /* keep only global or weak symbols */
 826                                 if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL &&
 827                                     GELF_ST_BIND(sym.st_info) != STB_WEAK)
 828                                         continue;
 829
 830                                 /* keep only defined symbols */
 831                                 if (sym.st_shndx == SHN_UNDEF)
 832                                         continue;
 833
 834                                 if ((name = elf_strptr(e, tabndx,
 835                                     sym.st_name)) == NULL) {
 836                                         bsdar_warnc(bsdar, EX_SOFTWARE, 0,
 837                                             "elf_strptr failed: %s",
 838                                              elf_errmsg(-1));
 839                                         continue;
 840                                 }
 841
 842                                 add_to_ar_sym_table(bsdar, name);
 843                         }
 844                 }
 845         }
 846         elferr = elf_errno();
 847         if (elferr != 0)
 848                 bsdar_warnc(bsdar, EX_SOFTWARE, 0, "elf_nextscn failed: %s",
 849                      elf_errmsg(elferr));
 850
 851         elf_end(e);
 852 }
 853
 854 /*
 855  * Append to the archive string table buffer.
 856  */
 857 static void
 858 add_to_ar_str_table(struct bsdar *bsdar, const char *name)
 859 {
 860
 861         if (bsdar->as == NULL) {
 862                 bsdar->as_cap = _INIT_AS_CAP;
 863                 bsdar->as_sz = 0;
 864                 if ((bsdar->as = malloc(bsdar->as_cap)) == NULL)
 865                         bsdar_errc(bsdar, EX_SOFTWARE, errno, "malloc failed");
 866         }
 867
 868         /*
 869          * The space required for holding one member name in as table includes:
 870          * strlen(name) + (1 for '/') + (1 for '\n') + (possibly 1 for padding).
 871          */
 872         while (bsdar->as_sz + strlen(name) + 3 > bsdar->as_cap) {
 873                 bsdar->as_cap *= 2;
 874                 bsdar->as = realloc(bsdar->as, bsdar->as_cap);
 875                 if (bsdar->as == NULL)
 876                         bsdar_errc(bsdar, EX_SOFTWARE, errno, "realloc failed");
 877         }
 878         strncpy(&bsdar->as[bsdar->as_sz], name, strlen(name));
 879         bsdar->as_sz += strlen(name);
 880         bsdar->as[bsdar->as_sz++] = '/';
 881         bsdar->as[bsdar->as_sz++] = '\n';
 882 }
 883
 884 /*
 885  * Append to the archive symbol table buffer.
 886  */
 887 static void
 888 add_to_ar_sym_table(struct bsdar *bsdar, const char *name)
 889 {
 890
 891         if (bsdar->s_so == NULL) {
 892                 if ((bsdar->s_so = malloc(_INIT_SYMOFF_CAP)) ==
 893                     NULL)
 894                         bsdar_errc(bsdar, EX_SOFTWARE, errno, "malloc failed");
 895                 bsdar->s_so_cap = _INIT_SYMOFF_CAP;
 896                 bsdar->s_cnt = 0;
 897         }
 898
 899         if (bsdar->s_sn == NULL) {
 900                 if ((bsdar->s_sn = malloc(_INIT_SYMNAME_CAP)) == NULL)
 901                         bsdar_errc(bsdar, EX_SOFTWARE, errno, "malloc failed");
 902                 bsdar->s_sn_cap = _INIT_SYMNAME_CAP;
 903                 bsdar->s_sn_sz = 0;
 904         }
 905
 906         if (bsdar->s_cnt * sizeof(uint32_t) >= bsdar->s_so_cap) {
 907                 bsdar->s_so_cap *= 2;
 908                 bsdar->s_so = realloc(bsdar->s_so, bsdar->s_so_cap);
 909                 if (bsdar->s_so == NULL)
 910                         bsdar_errc(bsdar, EX_SOFTWARE, errno, "realloc failed");
 911         }
 912         bsdar->s_so[bsdar->s_cnt] = bsdar->rela_off;
 913         bsdar->s_cnt++;
 914
 915         /*
 916          * The space required for holding one symbol name in sn table includes:
 917          * strlen(name) + (1 for '\n') + (possibly 1 for padding).
 918          */
 919         while (bsdar->s_sn_sz + strlen(name) + 2 > bsdar->s_sn_cap) {
 920                 bsdar->s_sn_cap *= 2;
 921                 bsdar->s_sn = realloc(bsdar->s_sn, bsdar->s_sn_cap);
 922                 if (bsdar->s_sn == NULL)
 923                         bsdar_errc(bsdar, EX_SOFTWARE, errno, "realloc failed");
 924         }
 925         strncpy(&bsdar->s_sn[bsdar->s_sn_sz], name, strlen(name));
 926         bsdar->s_sn_sz += strlen(name);
 927         bsdar->s_sn[bsdar->s_sn_sz++] = '\0';
 928 }