path: root/src/ar.c

/* Create, modify, and extract from archives.
   Copyright (C) 2005, 2007 Red Hat, Inc.
   Written by Ulrich Drepper <drepper@redhat.com>, 2005.

   Red Hat elfutils is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by the
   Free Software Foundation; version 2 of the License.

   Red Hat elfutils is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License along
   with Red Hat elfutils; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.

   Red Hat elfutils is an included package of the Open Invention Network.
   An included package of the Open Invention Network is a package for which
   Open Invention Network licensees cross-license their patents.  No patent
   license is granted, either expressly or impliedly, by designation as an
   included package.  Should you wish to participate in the Open Invention
   Network licensing program, please visit www.openinventionnetwork.com
   <http://www.openinventionnetwork.com>.  */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif

#include <argp.h>
#include <assert.h>
#include <error.h>
#include <fcntl.h>
#include <gelf.h>
#include <libintl.h>
#include <locale.h>
#include <mcheck.h>
#include <search.h>
#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/statfs.h>
#include <sys/time.h>

#include <system.h>

#include "arlib.h"


/* Name and version of program.  */
static void print_version (FILE *stream, struct argp_state *state);
void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;
/* Prototypes for local functions.  */
static int do_oper_extract (int oper, const char *arfname, char **argv,
			    int argc, long int instance);
static int do_oper_delete (const char *arfname, char **argv, int argc,
			   long int instance);
static int do_oper_insert (int oper, const char *arfname, char **argv,
			   int argc, const char *member);


/* Bug report address.  */
const char *argp_program_bug_address = PACKAGE_BUGREPORT;


/* Definitions of arguments for argp functions.  */
static const struct argp_option options[] =
{
  { NULL, 0, NULL, 0, N_("Commands:"), 0 },
  { NULL, 'd', NULL, 0, N_("Delete files from archive."), 0 },
  { NULL, 'm', NULL, 0, N_("Move files in archive."), 0 },
  { NULL, 'p', NULL, 0, N_("Print files in archive."), 0 },
  { NULL, 'q', NULL, 0, N_("Quick append files to archive."), 0 },
  { NULL, 'r', NULL, 0,
    N_("Replace existing or insert new file into archive."), 0 },
  { NULL, 't', NULL, 0, N_("Display content of archive."), 0 },
  { NULL, 'x', NULL, 0, N_("Extract files from archive."), 0 },

  { NULL, 0, NULL, 0, N_("Command Modifiers:"), 0 },
  { NULL, 'o', NULL, 0, N_("Preserve original dates."), 0 },
  { NULL, 'N', NULL, 0, N_("Use instance [COUNT] of name."), 0 },
  { NULL, 'C', NULL, 0,
    N_("Do not replace existing files with extracted files."), 0 },
  { NULL, 'T', NULL, 0, N_("Allow filename to be truncated if necessary."),
    0 },
  { NULL, 'v', NULL, 0, N_("Provide verbose output."), 0 },
  { NULL, 's', NULL, 0, N_("Force regeneration of symbol table."), 0 },
  { NULL, 'a', NULL, 0, N_("Insert file after [MEMBER]."), 0 },
  { NULL, 'b', NULL, 0, N_("Insert file before [MEMBER]."), 0 },
  { NULL, 'i', NULL, 0, N_("Same as -b."), 0 },
  { NULL, 'c', NULL, 0, N_("Suppress message when library has to be created."),
    0 },
  { NULL, 'P', NULL, 0, N_("Use full path for file matching."), 0 },
  { NULL, 'u', NULL, 0, N_("Update only older files in archive."), 0 },

  { NULL, 0, NULL, 0, NULL, 0 }
};

/* Short description of program.  */
static const char doc[] = N_("Create, modify, and extract from archives.");

/* Strings for arguments in help texts.  */
static const char args_doc[] = N_("[MEMBER] [COUNT] ARCHIVE [FILE...]");

/* Prototype for option handler.  */
static error_t parse_opt (int key, char *arg, struct argp_state *state);

/* Data structure to communicate with argp functions.  */
static struct argp argp =
{
  options, parse_opt, args_doc, doc, NULL, NULL, NULL
};


/* What operation to perform.  */
static enum
  {
    oper_none,
    oper_delete,
    oper_move,
    oper_print,
    oper_qappend,
    oper_replace,
    oper_list,
    oper_extract
  } operation;

/* Modifiers.  */
static bool verbose;
static bool preserve_dates;
static bool instance_specifed;
static bool dont_replace_existing;
static bool allow_truncate_fname;
static bool force_symtab;
static bool suppress_create_msg;
static bool full_path;
static bool update_newer;
static enum { ipos_none, ipos_before, ipos_after } ipos;


int
main (int argc, char *argv[])
{
  /* Make memory leak detection possible.  */
  mtrace ();

  /* We use no threads here which can interfere with handling a stream.  */
  (void) __fsetlocking (stdin, FSETLOCKING_BYCALLER);
  (void) __fsetlocking (stdout, FSETLOCKING_BYCALLER);
  (void) __fsetlocking (stderr, FSETLOCKING_BYCALLER);

  /* Set locale.  */
  (void) setlocale (LC_ALL, "");

  /* Make sure the message catalog can be found.  */
  (void) bindtextdomain (PACKAGE, LOCALEDIR);

  /* Initialize the message catalog.  */
  (void) textdomain (PACKAGE);

  /* For historical reasons the options in the first parameter need
     not be preceded by a dash.  Add it now if necessary.  */
  if (argc > 1 && argv[1][0] != '-')
    {
      size_t len = strlen (argv[1]) + 1;
      char *newp = alloca (len + 1);
      newp[0] = '-';
      memcpy (&newp[1], argv[1], len);
      argv[1] = newp;
    }

  /* Parse and process arguments.  */
  int remaining;
  (void) argp_parse (&argp, argc, argv, ARGP_IN_ORDER, &remaining, NULL);

  /* Tell the library which version we are expecting.  */
  (void) elf_version (EV_CURRENT);

  /* Handle the [MEMBER] parameter.  */
  const char *member = NULL;
  if (ipos != ipos_none)
    {
      /* Only valid for certain operations.  */
      if (operation == oper_extract && operation == oper_delete)
	error (1, 0, gettext ("\
'a', 'b', and 'i' are only allowed with the 'm' and 'r' options"));

      if (remaining == argc)
	{
	  error (0, 0, gettext ("MEMBER parameter required"));
	  argp_help (&argp, stderr, ARGP_HELP_SEE, AR);
	  exit (EXIT_FAILURE);
	}

      member = argv[remaining++];
    }

  /* Handle the [COUNT] parameter.  */
  long int instance = -1;
  if (instance_specifed)
    {
      /* Only valid for certain operations.  */
      if (operation == oper_extract && operation == oper_delete)
	error (1, 0, gettext ("\
'N' is only meaningful with the 'x' and 'd' options"));

      if (remaining == argc)
	{
	  error (0, 0, gettext ("COUNT parameter required"));
	  argp_help (&argp, stderr, ARGP_HELP_SEE, AR);
	  exit (EXIT_FAILURE);
	}

      char *endp;
      errno = 0;
      if (((instance = strtol (argv[remaining], &endp, 10)) == LONG_MAX
	   && errno == ERANGE)
	  || instance <= 0
	  || *endp != '\0')
	error (1, 0, gettext ("invalid COUNT parameter %s"), argv[remaining]);

      ++remaining;
    }

  if ((dont_replace_existing || allow_truncate_fname)
      && unlikely (operation != oper_extract))
    error (1, 0, gettext ("'%' is only meaningful with the 'x' option"),
	   dont_replace_existing ? 'C' : 'T');

  /* There must at least be one more parameter specifying the archive.   */
  if (remaining == argc)
    {
      error (0, 0, gettext ("Archive name required"));
      argp_help (&argp, stderr, ARGP_HELP_SEE, AR);
      exit (EXIT_FAILURE);
    }

  const char *arfname = argv[remaining++];
  argv += remaining;
  argc -= remaining;

  int status;
  switch (operation)
    {
    case oper_list:
    case oper_print:
      status = do_oper_extract (operation, arfname, argv, argc, -1);
      break;

    case oper_extract:
      status = do_oper_extract (operation, arfname, argv, argc, instance);
      break;

    case oper_delete:
      status = do_oper_delete (arfname, argv, argc, instance);
      break;

    case oper_move:
    case oper_qappend:
    case oper_replace:
      status = do_oper_insert (operation, arfname, argv, argc, member);
      break;

    default:
      assert (! "should not happen");
      status = 1;
      break;
    }

  return status;
}


/* Print the version information.  */
static void
print_version (FILE *stream, struct argp_state *state __attribute__ ((unused)))
{
  fprintf (stream, "ar (%s) %s\n", PACKAGE_NAME, VERSION);
  fprintf (stream, gettext ("\
Copyright (C) %s Red Hat, Inc.\n\
This is free software; see the source for copying conditions.  There is NO\n\
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
"), "2007");
  fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
}


/* Handle program arguments.  */
static error_t
parse_opt (int key, char *arg __attribute__ ((unused)),
	   struct argp_state *state __attribute__ ((unused)))
{
  switch (key)
    {
    case 'd':
    case 'm':
    case 'p':
    case 'q':
    case 'r':
    case 't':
    case 'x':
      if (operation != oper_none)
	{
	  error (0, 0, gettext ("More than one operation specified"));
	  argp_help (&argp, stderr, ARGP_HELP_SEE, AR);
	  exit (EXIT_FAILURE);
	}

      switch (key)
	{
	case 'd':
	  operation = oper_delete;
	  break;
	case 'm':
	  operation = oper_move;
	  break;
	case 'p':
	  operation = oper_print;
	  break;
	case 'q':
	  operation = oper_qappend;
	  break;
	case 'r':
	  operation = oper_replace;
	  break;
	case 't':
	  operation = oper_list;
	  break;
	case 'x':
	  operation = oper_extract;
	  break;
	}
      break;

    case 'a':
      ipos = ipos_after;
      break;

    case 'b':
    case 'i':
      ipos = ipos_before;
      break;

    case 'c':
      suppress_create_msg = true;
      break;

    case 'C':
      dont_replace_existing = true;
      break;

    case 'N':
      instance_specifed = true;
      break;

    case 'o':
      preserve_dates = true;
      break;

    case 'P':
      full_path = true;
      break;

    case 's':
      force_symtab = true;
      break;

    case 'T':
      allow_truncate_fname = true;
      break;

    case 'v':
      verbose = true;
      break;

    default:
      return ARGP_ERR_UNKNOWN;
    }
  return 0;
}


static int
open_archive (const char *arfname, int flags, int mode, Elf **elf,
	      struct stat *st, bool miss_allowed)
{
  int fd = open (arfname, flags, mode);
  if (fd == -1)
    {
      if (miss_allowed)
	return -1;

      error (EXIT_FAILURE, errno, gettext ("cannot open archive '%s'"),
	     arfname);
    }

  if (elf != NULL)
    {
      Elf_Cmd cmd = flags == O_RDONLY ? ELF_C_READ_MMAP : ELF_C_RDWR_MMAP;

      *elf = elf_begin (fd, cmd, NULL);
      if (*elf == NULL)
	error (EXIT_FAILURE, 0, gettext ("cannot open archive '%s': %s"),
	       arfname, elf_errmsg (-1));

      if (flags == O_RDONLY && elf_kind (*elf) != ELF_K_AR)
	error (EXIT_FAILURE, 0, gettext ("%s: not an archive file"), arfname);
    }

  if (st != NULL && fstat (fd, st) != 0)
    error (EXIT_FAILURE, errno, gettext ("cannot stat archive '%s'"),
	   arfname);

  return fd;
}


static void
not_found (int argc, char *argv[argc], bool found[argc])
{
  for (int i = 0; i < argc; ++i)
    if (!found[i])
      printf (gettext ("no entry %s in archive\n"), argv[i]);
}


static int
copy_content (Elf *elf, int newfd, off_t off, size_t n)
{
  size_t len;
  char *rawfile = elf_rawfile (elf, &len);

  assert (off + n <= len);

  /* Tell the kernel we will read all the pages sequentially.  */
  size_t ps = sysconf (_SC_PAGESIZE);
  if (n > 2 * ps)
    posix_madvise (rawfile + (off & ~(ps - 1)), n, POSIX_MADV_SEQUENTIAL);

  return write_retry (newfd, rawfile + off, n) != (ssize_t) n;
}


static int
do_oper_extract (int oper, const char *arfname, char **argv, int argc,
		 long int instance)
{
  bool found[argc];
  memset (found, '\0', sizeof (found));

  struct statfs f;
  f.f_namelen = 0;

  off_t index_off = -1;
  size_t index_size = 0;
  off_t cur_off = SARMAG;

  int status = 0;
  Elf *elf;
  int fd = open_archive (arfname, O_RDONLY, 0, &elf, NULL, false);

  if (hcreate (2 * argc) == 0)
    error (EXIT_FAILURE, errno, gettext ("cannot create hash table"));

  for (int cnt = 0; cnt < argc; ++cnt)
    {
      ENTRY entry = { .key = argv[cnt], .data = &argv[cnt] };
      if (hsearch (entry, ENTER) == NULL)
	error (EXIT_FAILURE, errno,
	       gettext ("cannot insert into hash table"));
    }

  struct stat st;
  if (force_symtab)
    {
      if (fstat (fd, &st) != 0)
	{
	  error (0, errno, gettext ("cannot stat '%s'"), arfname);
	  close (fd);
	  return 1;
	}
      arlib_init ();
    }

  Elf_Cmd cmd = ELF_C_READ_MMAP;
  Elf *subelf;
  while ((subelf = elf_begin (fd, cmd, elf)) != NULL)
    {
      Elf_Arhdr *arhdr = elf_getarhdr (subelf);

      if (strcmp (arhdr->ar_name, "/") == 0)
	{
	  index_off = elf_getaroff (subelf);
	  index_size = arhdr->ar_size;
	  goto next;
	}
      if (strcmp (arhdr->ar_name, "//") == 0)
	goto next;

      if (force_symtab)
	{
	  arlib_add_symbols (elf, arfname, arhdr->ar_name, cur_off);
	  cur_off += (((arhdr->ar_size + 1) & ~((off_t) 1))
		      + sizeof (struct ar_hdr));
	}

      bool do_extract = argc <= 0;
      if (!do_extract)
	{
	  ENTRY entry;
	  entry.key = arhdr->ar_name;
	  ENTRY *res = hsearch (entry, FIND);
	  if (res != NULL && (instance < 0 || instance-- == 0)
	      && !found[(char **) res->data - argv])
	    found[(char **) res->data - argv] = do_extract = true;
	}

      if (do_extract)
	{
	  if (verbose)
	    {
	      if (oper == oper_print)
		{
		  printf ("\n<%s>\n\n", arhdr->ar_name);

		  /* We have to flush now because now we use the descriptor
		     directly.  */
		  fflush (stdout);
		}
	      else if (oper == oper_list)
		{
		  char datestr[100];
		  strftime (datestr, sizeof (datestr), "%b %e %H:%M %Y",
			    localtime (&arhdr->ar_date));

		  printf ("%c%c%c%c%c%c%c%c%c %u/%u %6ju %s %s\n",
			  (arhdr->ar_mode & S_IRUSR) ? 'r' : '-',
			  (arhdr->ar_mode & S_IWUSR) ? 'w' : '-',
			  (arhdr->ar_mode & S_IXUSR)
			  ? ((arhdr->ar_mode & S_ISUID) ? 's' : 'x')
			  : ((arhdr->ar_mode & S_ISUID) ? 'S' : '-'),
			  (arhdr->ar_mode & S_IRGRP) ? 'r' : '-',
			  (arhdr->ar_mode & S_IWGRP) ? 'w' : '-',
			  (arhdr->ar_mode & S_IXGRP)
			  ? ((arhdr->ar_mode & S_ISGID) ? 's' : 'x')
			  : ((arhdr->ar_mode & S_ISGID) ? 'S' : '-'),
			  (arhdr->ar_mode & S_IROTH) ? 'r' : '-',
			  (arhdr->ar_mode & S_IWOTH) ? 'w' : '-',
			  (arhdr->ar_mode & S_IXOTH)
			  ? ((arhdr->ar_mode & S_ISVTX) ? 't' : 'x')
			  : ((arhdr->ar_mode & S_ISVTX) ? 'T' : '-'),
			  arhdr->ar_uid,
			  arhdr->ar_gid,
			  (uintmax_t) arhdr->ar_size,
			  datestr,
			  arhdr->ar_name);
		}
	      else
		printf ("x - %s\n", arhdr->ar_name);
	    }

	  if (oper == oper_list)
	    {
	      if (!verbose)
		puts (arhdr->ar_name);

	      goto next;
	    }

	  size_t nleft;
	  char *data = elf_rawfile (subelf, &nleft);
	  if (data == NULL)
	    {
	      error (0, 0, gettext ("cannot read content of %s: %s"),
		     arhdr->ar_name, elf_errmsg (-1));
	      status = 1;
	      goto next;
	    }

	  int xfd;
	  char tempfname[] = "XXXXXX";
	  bool use_mkstemp = true;

	  if (oper == oper_print)
	    xfd = STDOUT_FILENO;
	  else
	    {
	      xfd = mkstemp (tempfname);
	      if (unlikely (xfd == -1))
		{
		  /* We cannot create a temporary file.  Try to overwrite
		     the file or create it if it does not exist.  */
		  int flags = O_WRONLY | O_CREAT;
		  if (dont_replace_existing)
		    flags |= O_EXCL;
		  else
		    flags |= O_TRUNC;
		  xfd = open (arhdr->ar_name, flags, 0600);
		  if (unlikely (xfd == -1))
		    {
		      int printlen = INT_MAX;

		      if (errno == ENAMETOOLONG && allow_truncate_fname
			  && (f.f_namelen != 0 || statfs (".", &f) == 0))
			{
			  /* Try to truncate the name.  First find out by how
			     much.  */
			  printlen = f.f_namelen;
			  char truncfname[f.f_namelen + 1];
			  *((char *) mempcpy (truncfname, arhdr->ar_name,
					      f.f_namelen)) = '\0';

			  xfd = open (truncfname, flags, 0600);
			}

		      if (xfd == -1)
			{
			  error (0, errno, gettext ("cannot open %.*s"),
				 (int) printlen, arhdr->ar_name);
			  status = 1;
			  goto next;
			}
		    }

		  use_mkstemp = false;
		}
	    }

	  ssize_t n;
	  while ((n = TEMP_FAILURE_RETRY (write (xfd, data, nleft))) != -1)
	    {
	      nleft -= n;
	      if (nleft == 0)
		break;
	      data += n;
	    }

	  if (unlikely (n == -1))
	    {
	      error (0, errno, gettext ("failed to write %s"), arhdr->ar_name);
	      status = 1;
	      unlink (tempfname);
	      close (xfd);
	      goto next;
	    }

	  if (oper != oper_print)
	    {
	      /* Fix up the mode.  */
	      if (unlikely (fchmod (xfd, arhdr->ar_mode) != 0))
		{
		  error (0, errno, gettext ("cannot change mode of %s"),
			 arhdr->ar_name);
		  status = 0;
		}

	      if (preserve_dates)
		{
		  struct timeval tv[2];
		  tv[0].tv_sec = arhdr->ar_date;
		  tv[0].tv_usec = 0;
		  tv[1].tv_sec = arhdr->ar_date;
		  tv[1].tv_usec = 0;

		  if (unlikely (futimes (xfd, tv) != 0))
		    {
		      error (0, errno,
			     gettext ("cannot change modification time of %s"),
			     arhdr->ar_name);
		      status = 1;
		    }
		}

	      /* If we used a temporary file, move it do the right
		 name now.  */
	      if (use_mkstemp)
		{
		  int r;

		  if (dont_replace_existing)
		    {
		      r = link (tempfname, arhdr->ar_name);
		      if (likely (r == 0))
			unlink (tempfname);
		    }
		  else
		    r = rename (tempfname, arhdr->ar_name);

		  if (unlikely (r) != 0)
		    {
		      int printlen = INT_MAX;

		      if (errno == ENAMETOOLONG && allow_truncate_fname
			  && (f.f_namelen != 0 || statfs (".", &f) == 0))
			{
			  /* Try to truncate the name.  First find out by how
			     much.  */
			  printlen = f.f_namelen;
			  char truncfname[f.f_namelen + 1];
			  *((char *) mempcpy (truncfname, arhdr->ar_name,
					      f.f_namelen)) = '\0';

			  if (dont_replace_existing)
			    {
			      r = link (tempfname, truncfname);
			      if (likely (r == 0))
				unlink (tempfname);
			    }
			  else
			    r = rename (tempfname, truncfname);
			}

		      if (r != 0)
			{
			  error (0, errno, gettext ("\
cannot rename temporary file to %.*s"),
				 printlen, arhdr->ar_name);
			  unlink (tempfname);
			  status = 1;
			}
		    }
		}

	      close (xfd);
	    }
	}

    next:
      cmd = elf_next (subelf);
      if (elf_end (subelf) != 0)
	error (1, 0, "%s: %s", arfname, elf_errmsg (-1));
    }

  hdestroy ();

  if (force_symtab)
    {
      arlib_finalize ();

      if (symtab.symsnamelen != 0
	  /* We have to rewrite the file also if it initially had an index
	     but now does not need one anymore.  */
	  || (symtab.symsnamelen == 0 && index_size != 0))
	{
	  char tmpfname[strlen (arfname) + 7];
	  strcpy (stpcpy (tmpfname, arfname), "XXXXXX");
	  int newfd = mkstemp (tmpfname);
	  if (unlikely (newfd == -1))
	    {
	    nonew:
	      error (0, errno, gettext ("cannot create new file"));
	      status = 1;
	    }
	  else
	    {
	      /* Create the header.  */
	      if (unlikely (write_retry (newfd, ARMAG, SARMAG) != SARMAG))
		{
		  // XXX Use /prof/self/fd/%d ???
		nonew_unlink:
		  unlink (tmpfname);
		  if (newfd != -1)
		    close (newfd);
		  goto nonew;
		}

	      /* Create the new file.  There are three parts as far we are
		 concerned: 1. original context before the index, 2. the
		 new index, 3. everything after the new index.  */
	      off_t rest_off;
	      if (index_off != -1)
		rest_off = (index_off + sizeof (struct ar_hdr)
			    + ((index_size + 1) & ~1ul));
	      else
		rest_off = SARMAG;

	      if ((symtab.symsnamelen != 0
		   && ((write_retry (newfd, symtab.symsoff,
				     symtab.symsofflen)
			!= (ssize_t) symtab.symsofflen)
		       || (write_retry (newfd, symtab.symsname,
					symtab.symsnamelen)
			   != (ssize_t) symtab.symsnamelen)))
		  /* Even if the original file had content before the
		     symbol table, we write it in the correct order.  */
		  || (index_off != SARMAG
		      && copy_content (elf, newfd, SARMAG, index_off - SARMAG))
		  || copy_content (elf, newfd, rest_off, st.st_size - rest_off)
		  /* Set the mode of the new file to the same values the
		     original file has.  */
		  || fchmod (newfd, st.st_mode & ALLPERMS) != 0
		  /* Never complain about fchown failing.  */
		  || (fchown (newfd, st.st_uid, st.st_gid),
		      close (newfd) != 0)
		  || (newfd = -1, rename (tmpfname, arfname) != 0))
		goto nonew_unlink;
	    }
	}
    }

  elf_end (elf);

  close (fd);

  not_found (argc, argv, found);

  return status;
}


struct armem
{
  off_t off;
  off_t old_off;
  size_t size;
  long int long_name_off;
  struct armem *next;
  void *mem;
  time_t sec;
  uid_t uid;
  gid_t gid;
  mode_t mode;
  const char *name;
  Elf *elf;
};


static int
write_member (struct armem *memb, off_t *startp, off_t *lenp, Elf *elf,
	      off_t end_off, int newfd)
{
  struct ar_hdr arhdr;
  char tmpbuf[sizeof (arhdr.ar_name) + 1];

  bool changed_header = memb->long_name_off != -1;
  if (changed_header)
    {
      /* In case of a long file name we assume the archive header
	 changed and we write it here.  */
      memcpy (&arhdr, elf_rawfile (elf, NULL) + *startp, sizeof (arhdr));

      snprintf (tmpbuf, sizeof (tmpbuf), "/%-*ld",
		(int) sizeof (arhdr.ar_name), memb->long_name_off);
      changed_header = memcmp (arhdr.ar_name, tmpbuf,
			       sizeof (arhdr.ar_name)) != 0;
    }

  /* If the files are adjacent in the old file extend the range.  */
  if (*startp != -1 && !changed_header && *startp + *lenp == memb->old_off)
    {
      /* Extend the current range.  */
      *lenp += (memb->next != NULL
		? memb->next->off : end_off) - memb->off;
      return 0;
    }

  /* Write out the old range.  */
  if (*startp != -1 && copy_content (elf, newfd, *startp, *lenp))
    return -1;

  *startp = memb->old_off;
  *lenp = (memb->next != NULL ? memb->next->off : end_off) - memb->off;

  if (changed_header)
    {
      memcpy (arhdr.ar_name, tmpbuf, sizeof (arhdr.ar_name));

      if (unlikely (write_retry (newfd, &arhdr, sizeof (arhdr))
		    != sizeof (arhdr)))
	return -1;

      *startp += sizeof (struct ar_hdr);
      assert ((size_t) *lenp >= sizeof (struct ar_hdr));
      *lenp -= sizeof (struct ar_hdr);
    }

  return 0;
}


static int
do_oper_delete (const char *arfname, char **argv, int argc,
		long int instance)
{
  bool *found = alloca (sizeof (bool) * argc);
  memset (found, '\0', sizeof (found));

  /* List of the files we keep.  */
  struct armem *to_copy = NULL;

  int status = 0;
  Elf *elf;
  struct stat st;
  int fd = open_archive (arfname, O_RDONLY, 0, &elf, &st, false);

  if (hcreate (2 * argc) == 0)
    error (EXIT_FAILURE, errno, gettext ("cannot create hash table"));

  for (int cnt = 0; cnt < argc; ++cnt)
    {
      ENTRY entry = { .key = argv[cnt], .data = &argv[cnt] };
      if (hsearch (entry, ENTER) == NULL)
	error (EXIT_FAILURE, errno,
	       gettext ("cannot insert into hash table"));
    }

  arlib_init ();

  off_t cur_off = SARMAG;
  Elf_Cmd cmd = ELF_C_READ_MMAP;
  Elf *subelf;
  while ((subelf = elf_begin (fd, cmd, elf)) != NULL)
    {
      Elf_Arhdr *arhdr = elf_getarhdr (subelf);

      /* Ignore the symbol table and the long file name table here.  */
      if (strcmp (arhdr->ar_name, "/") == 0
	  || strcmp (arhdr->ar_name, "//") == 0)
	goto next;

      bool do_delete = argc <= 0;
      if (!do_delete)
	{
	  ENTRY entry;
	  entry.key = arhdr->ar_name;
	  ENTRY *res = hsearch (entry, FIND);
	  if (res != NULL && (instance < 0 || instance-- == 0)
	      && !found[(char **) res->data - argv])
	    found[(char **) res->data - argv] = do_delete = true;
	}

      if (do_delete)
	{
	  if (verbose)
	    printf ("d - %s\n", arhdr->ar_name);
	}
      else
	{
	  struct armem *newp = alloca (sizeof (struct armem));
	  newp->old_off = elf_getaroff (subelf);
	  newp->off = cur_off;

	  cur_off += (((arhdr->ar_size + 1) & ~((off_t) 1))
		      + sizeof (struct ar_hdr));

	  if (to_copy == NULL)
	    to_copy = newp->next = newp;
	  else
	    {
	      newp->next = to_copy->next;
	      to_copy = to_copy->next = newp;
	    }

	  /* If we recreate the symbol table read the file's symbol
	     table now.  */
	  arlib_add_symbols (subelf, arfname, arhdr->ar_name, newp->off);

	  /* Remember long file names.  */
	  size_t ar_namelen = strlen (arhdr->ar_name);
	  if (ar_namelen > MAX_AR_NAME_LEN)
	    newp->long_name_off = arlib_add_long_name (arhdr->ar_name,
						       ar_namelen);
	  else
	    newp->long_name_off = -1l;
	}

    next:
      cmd = elf_next (subelf);
      if (elf_end (subelf) != 0)
	error (1, 0, "%s: %s", arfname, elf_errmsg (-1));
    }

  arlib_finalize ();

  hdestroy ();

  /* Create a new, temporary file in the same directory as the
     original file.  */
  char tmpfname[strlen (arfname) + 7];
  strcpy (stpcpy (tmpfname, arfname), "XXXXXX");
  int newfd = mkstemp (tmpfname);
  if (unlikely (newfd == -1))
    goto nonew;

  /* Create the header.  */
  if (unlikely (write_retry (newfd, ARMAG, SARMAG) != SARMAG))
    {
      // XXX Use /prof/self/fd/%d ???
    nonew_unlink:
      unlink (tmpfname);
      if (newfd != -1)
	close (newfd);
    nonew:
      error (0, errno, gettext ("cannot create new file"));
      status = 1;
      goto errout;
    }

  /* If the archive is empty that is all we have to do.  */
  if (likely (to_copy != NULL))
    {
      /* Write the symbol table or the long file name table or both.  */
      if (symtab.symsnamelen != 0
	  && ((write_retry (newfd, symtab.symsoff, symtab.symsofflen)
	       != (ssize_t) symtab.symsofflen)
	      || (write_retry (newfd, symtab.symsname, symtab.symsnamelen)
		  != (ssize_t) symtab.symsnamelen)))
	goto nonew_unlink;

      if (symtab.longnameslen > sizeof (struct ar_hdr)
	  && (write_retry (newfd, symtab.longnames, symtab.longnameslen)
	      != (ssize_t) symtab.longnameslen))
	goto nonew_unlink;

      /* NULL-terminate the list of files to copy.  */
      struct armem *last = to_copy;
      to_copy = to_copy->next;
      last->next = NULL;

      off_t start = -1;
      off_t len = -1;

      do
	if (write_member (to_copy, &start, &len, elf, cur_off, newfd) != 0)
	  goto nonew_unlink;
      while ((to_copy = to_copy->next) != NULL);

      /* Write the last part.  */
      if (copy_content (elf, newfd, start, len))
	goto nonew_unlink;
    }

  /* Set the mode of the new file to the same values the original file
     has.  */
  if (fchmod (newfd, st.st_mode & ALLPERMS) != 0
      /* Never complain about fchown failing.  */
      || (fchown (newfd, st.st_uid, st.st_gid),
	  close (newfd) != 0)
      || (newfd = -1, rename (tmpfname, arfname) != 0))
    goto nonew_unlink;

 errout:
#ifdef DEBUG
  elf_end (elf);

  arlib_fini ();

  close (fd);
#endif

  not_found (argc, argv, found);

  return status;
}


static void
no0print (bool ofmt, char *buf, int bufsize, long int val)
{
  char tmpbuf[bufsize + 1];
  snprintf (tmpbuf, sizeof (tmpbuf), ofmt ? "%-*lo" : "%-*ld", bufsize, val);
  memcpy (buf, tmpbuf, bufsize);
}


static int
do_oper_insert (int oper, const char *arfname, char **argv, int argc,
		const char *member)
{
  int status = 0;
  Elf *elf;
  struct stat st;
  int fd = open_archive (arfname, O_RDONLY, 0, &elf, &st, oper != oper_move);

  /* List of the files we keep.  */
  struct armem *all = NULL;
  struct armem *after_memberelem = NULL;
  struct armem **found = alloca (sizeof (*found) * argc);
  memset (found, '\0', sizeof (*found) * argc);

  arlib_init ();

  if (fd == -1)
    {
      if (!suppress_create_msg)
	fprintf (stderr, "%s: creating %s\n", AR, arfname);

      goto no_old;
    }

  /* Store the names of all files from the command line in a hash
     table so that we can match it.  Note that when no file name is
     given we are basically doing nothing except recreating the
     index.  */
  if (oper != oper_qappend)
    {
      if (hcreate (2 * argc) == 0)
	error (EXIT_FAILURE, errno, gettext ("cannot create hash table"));

      for (int cnt = 0; cnt < argc; ++cnt)
	{
	  ENTRY entry;
	  entry.key = full_path ? argv[cnt] : basename (argv[cnt]);
	  entry.data = &argv[cnt];
	  if (hsearch (entry, ENTER) == NULL)
	    error (EXIT_FAILURE, errno,
		   gettext ("cannot insert into hash table"));
	}
    }

  /* While iterating over the current content of the archive we must
     determine a number of things: which archive members to keep,
     which are replaced, and where to insert the new members.  */
  off_t cur_off = SARMAG;
  Elf_Cmd cmd = ELF_C_READ_MMAP;
  Elf *subelf;
  while ((subelf = elf_begin (fd, cmd, elf)) != NULL)
    {
      Elf_Arhdr *arhdr = elf_getarhdr (subelf);

      /* Ignore the symbol table and the long file name table here.  */
      if (strcmp (arhdr->ar_name, "/") == 0
	  || strcmp (arhdr->ar_name, "//") == 0)
	goto next;

      struct armem *newp = alloca (sizeof (struct armem));
      newp->old_off = elf_getaroff (subelf);
      newp->size = arhdr->ar_size;
      newp->sec = arhdr->ar_date;
      newp->mem = NULL;

      /* Remember long file names.  */
      size_t ar_namelen = strlen (arhdr->ar_name);
      if (ar_namelen > MAX_AR_NAME_LEN)
	newp->long_name_off = arlib_add_long_name (arhdr->ar_name, ar_namelen);
      else
	newp->long_name_off = -1l;

      /* Check whether this is a file we are looking for.  */
      if (oper != oper_qappend)
	{
	  /* Check whether this is the member used as the insert point.  */
	  if (member != NULL && strcmp (arhdr->ar_name, member) == 0)
	    {
	      /* Note that all == NULL means insert at the beginning.  */
	      if (ipos == ipos_before)
		after_memberelem = all;
	      else
		after_memberelem = newp;
	      member = NULL;
	    }

	  ENTRY entry;
	  entry.key = arhdr->ar_name;
	  ENTRY *res = hsearch (entry, FIND);
	  if (res != NULL && found[(char **) res->data - argv] == NULL)
	    {
	      found[(char **) res->data - argv] = newp;

	      /* If we insert before or after a certain element move
		 all files to a special list.  */
	      if (unlikely (ipos != ipos_none || oper == oper_move))
		{
		  if (after_memberelem == newp)
		    /* Since we remove this element even though we should
		       insert everything after it, we in fact insert
		       everything after the previous element.  */
		    after_memberelem = all;

		  goto next;
		}
	    }
	}

      if (all == NULL)
	all = newp->next = newp;
      else
	{
	  newp->next = all->next;
	  all = all->next = newp;
	}

    next:
      cmd = elf_next (subelf);
      if (elf_end (subelf) != 0)
	error (EXIT_FAILURE, 0, "%s: %s", arfname, elf_errmsg (-1));
    }

  if (oper != oper_qappend)
    hdestroy ();

 no_old:
  if (member != NULL)
    error (EXIT_FAILURE, 0, gettext ("position member %s not found"),
	   member);

  if (oper == oper_move)
    {
      /* Make sure all requested elements are found in the archive.  */
      for (int cnt = 0; cnt < argc; ++cnt)
	{
	  if (found[cnt] == NULL)
	    {
	      fprintf (stderr, gettext ("%s: no entry %s in archive!\n"),
		       AR, argv[cnt]);
	      status = 1;
	    }

	  if (verbose)
	    printf ("m - %s\n", argv[cnt]);
	}
    }
  else
    {
      /* Open all the new files, get their sizes and add all symbols.  */
      for (int cnt = 0; cnt < argc; ++cnt)
	{
	  const char *bname = basename (argv[cnt]);
	  if (found[cnt] == NULL)
	    {
	      found[cnt] = alloca (sizeof (struct armem));
	      found[cnt]->old_off = -1;

	      size_t ar_namelen = strlen (argv[cnt]);
	      if (ar_namelen > MAX_AR_NAME_LEN)
		found[cnt]->long_name_off = arlib_add_long_name (bname,
								 ar_namelen);
	      else
		found[cnt]->long_name_off = -1l;
	    }

	  struct stat newst;
	  Elf *newelf;
	  int newfd = open (argv[cnt], O_RDONLY);
	  if (newfd == -1)
	    {
	      error (0, errno, gettext ("cannot open %s"), argv[cnt]);
	      status = 1;
	    }
	  else if (fstat (newfd, &newst) == -1)
	    {
	      error (0, errno, gettext ("cannot stat %s"), argv[cnt]);
	      close (newfd);
	      status = 1;
	    }
	  else if (!S_ISREG (newst.st_mode))
	    {
	      error (0, errno, gettext ("%s is no regular file"), argv[cnt]);
	      close (newfd);
	      status = 1;
	    }
	  else if (update_newer
		   && found[cnt]->old_off != -1l
		   && found[cnt]->sec > st.st_mtime)
	    /* Do nothing, the file in the archive is younger.  */
	    close (newfd);
	  else if ((newelf = elf_begin (newfd, ELF_C_READ_MMAP, NULL))
		   == NULL)
	    {
	      fprintf (stderr,
		       gettext ("cannot get ELF descriptor for %s: %s\n"),
		       argv[cnt], elf_errmsg (-1));
	      status = 1;
	    }
	  else
	    {
	      if (verbose)
		printf ("%c - %s\n",
			found[cnt]->old_off == -1l ? 'a' : 'r', argv[cnt]);

#ifdef DEBUG
	      found[cnt]->elf = newelf;
#endif
	      found[cnt]->sec = newst.st_mtime;
	      found[cnt]->uid = newst.st_uid;
	      found[cnt]->gid = newst.st_gid;
	      found[cnt]->mode = newst.st_mode;
	      found[cnt]->name = basename (argv[cnt]);

	      found[cnt]->mem = elf_rawfile (newelf, &found[cnt]->size);
	      if (found[cnt] == NULL || elf_cntl (newelf, ELF_C_FDDONE) != 0)
		error (EXIT_FAILURE, 0, gettext ("cannot read %s: %s"),
		       argv[cnt], elf_errmsg (-1));

	      close (newfd);

	      /* Remember long file names.  */
	      size_t bnamelen = strlen (bname);
	      if (bnamelen > MAX_AR_NAME_LEN)
		found[cnt]->long_name_off = arlib_add_long_name (bname,
								 bnamelen);
	      else
		found[cnt]->long_name_off = -1l;
	    }
	}
    }

  if (status != 0)
    {
#ifdef DEBUG
      elf_end (elf);

      arlib_fini ();

      close (fd);
#endif

      return status;
    }

  /* If we have no entry point so far add at the end.  AFTER_MEMBERELEM
     being NULL when adding before an entry means add at the beginning.  */
  if (ipos != ipos_before && after_memberelem == NULL)
    after_memberelem = all;

  /* Convert the circular list into a normal list first.  */
  if (all != NULL)
    {
      struct armem *tmp = all;
      all = all->next;
      tmp->next = NULL;
    }

  struct armem *last_added = after_memberelem;
  for (int cnt = 0; cnt < argc; ++cnt)
    if (oper != oper_replace || found[cnt]->old_off == -1)
      {
	if (last_added == NULL)
	  {
	    found[cnt]->next = all;
	    last_added = all = found[cnt];
	  }
	else
	  {
	    found[cnt]->next = last_added->next;
	    last_added = last_added->next = found[cnt];
	  }
      }

  /* Finally compute the offset and add the symbols for the files
     after the insert point.  */
  if (likely (all != NULL))
    for (struct armem *memp = all; memp != NULL; memp = memp->next)
      {
	memp->off = cur_off;

	if (memp->mem == NULL)
	  {
	    Elf_Arhdr *arhdr;
	    /* Fake initializing arhdr and subelf to keep gcc calm.  */
	    asm ("" : "=m" (arhdr), "=m" (subelf));
	    if (elf_rand (elf, memp->old_off) == 0
		|| (subelf = elf_begin (fd, ELF_C_READ_MMAP, elf)) == NULL
		|| (arhdr = elf_getarhdr (subelf)) == NULL)
	      /* This should never happen since we already looked at the
		 archive content.  But who knows...  */
	      error (EXIT_FAILURE, 0, "%s: %s", arfname, elf_errmsg (-1));

	    arlib_add_symbols (subelf, arfname, arhdr->ar_name, cur_off);

	    elf_end (subelf);
	  }
	else
	  arlib_add_symbols (memp->elf, arfname, memp->name, cur_off);

	cur_off += (((memp->size + 1) & ~((off_t) 1))
		    + sizeof (struct ar_hdr));
      }

  /* Now we have all the information for the symbol table and long
     file name table.  Construct the final layout.  */
  arlib_finalize ();

  /* Create a new, temporary file in the same directory as the
     original file.  */
  char tmpfname[strlen (arfname) + 7];
  strcpy (stpcpy (tmpfname, arfname), "XXXXXX");
  int newfd;
  if (fd != -1)
    newfd = mkstemp (tmpfname);
  else
    {
      newfd = open (arfname, O_RDWR | O_CREAT | O_EXCL, DEFFILEMODE);
      if (newfd == -1 && errno == EEXIST)
	/* Bah, first the file did not exist, now it does.  Restart.  */
	return do_oper_insert (oper, arfname, argv, argc, member);
    }
  if (unlikely (newfd == -1))
    goto nonew;

  /* Create the header.  */
  if (unlikely (write_retry (newfd, ARMAG, SARMAG) != SARMAG))
    {
    nonew_unlink:
      if (fd != -1)
	{
	  // XXX Use /prof/self/fd/%d ???
	  unlink (tmpfname);
	  if (newfd != -1)
	    close (newfd);
	}
    nonew:
      error (0, errno, gettext ("cannot create new file"));
      status = 1;
      goto errout;
    }

  /* If the new archive is not empty we actually have something to do.  */
  if (likely (all != NULL))
    {
      /* Write the symbol table or the long file name table or both.  */
      if (symtab.symsnamelen != 0
	  && ((write_retry (newfd, symtab.symsoff, symtab.symsofflen)
	       != (ssize_t) symtab.symsofflen)
	      || (write_retry (newfd, symtab.symsname, symtab.symsnamelen)
		  != (ssize_t) symtab.symsnamelen)))
	goto nonew_unlink;

      if (symtab.longnameslen > sizeof (struct ar_hdr)
	  && (write_retry (newfd, symtab.longnames, symtab.longnameslen)
	      != (ssize_t) symtab.longnameslen))
	goto nonew_unlink;

      off_t start = -1;
      off_t len = -1;

      while (all != NULL)
	{
	  if (all->mem != NULL)
	    {
	      /* This is a new file.  If there is anything from the
		 archive left to be written do it now.  */
	      if (start != -1  && copy_content (elf, newfd, start, len))
		goto nonew_unlink;

	      start = -1;
	      len = -1;

	      /* Create the header.  */
	      struct ar_hdr arhdr;
	      char tmpbuf[sizeof (arhdr.ar_name) + 1];
	      if (all->long_name_off == -1)
		{
		  size_t namelen = strlen (all->name);
		  memset (mempcpy (arhdr.ar_name, all->name, namelen),
			  ' ', sizeof (arhdr.ar_name) - namelen);
		}
	      else
		{
		  snprintf (tmpbuf, sizeof (arhdr.ar_name) + 1, "/%-*ld",
			    (int) sizeof (arhdr.ar_name), all->long_name_off);
		  memcpy (arhdr.ar_name, tmpbuf, sizeof (arhdr.ar_name));
		}

	      no0print (false, arhdr.ar_date, sizeof (arhdr.ar_date),
			all->sec);
	      no0print (false, arhdr.ar_uid, sizeof (arhdr.ar_uid), all->uid);
	      no0print (false, arhdr.ar_gid, sizeof (arhdr.ar_gid), all->gid);
	      no0print (true, arhdr.ar_mode, sizeof (arhdr.ar_mode),
			all->mode);
	      no0print (false, arhdr.ar_size, sizeof (arhdr.ar_size),
			all->size);
	      memcpy (arhdr.ar_fmag, ARFMAG, sizeof (arhdr.ar_fmag));

	      if (unlikely (write_retry (newfd, &arhdr, sizeof (arhdr))
			    != sizeof (arhdr)))
		goto nonew_unlink;

	      /* Now the file itself.  */
	      if (unlikely (write_retry (newfd, all->mem, all->size)
			    != (off_t) all->size))
		goto nonew_unlink;

	      /* Pad the file if its size is odd.  */
	      if ((all->size & 1) != 0)
		write (newfd, "\n", 1);
	    }
	  else
	    {
	      /* This is a member from the archive.  */
	      if (write_member (all, &start, &len, elf, cur_off, newfd)
		  != 0)
		goto nonew_unlink;
	    }

	  all = all->next;
	}

      /* Write the last part.  */
      if (start != -1 && copy_content (elf, newfd, start, len))
	goto nonew_unlink;
    }

  /* Set the mode of the new file to the same values the original file
     has.  */
  if (fd != -1
      && (fchmod (newfd, st.st_mode & ALLPERMS) != 0
	  /* Never complain about fchown failing.  */
	  || (fchown (newfd, st.st_uid, st.st_gid),
	      close (newfd) != 0)
	  || (newfd = -1, rename (tmpfname, arfname) != 0)))
      goto nonew_unlink;

 errout:
#ifdef DEBUG
  elf_end (elf);

  arlib_fini ();

  close (fd);
#endif

  return status;
}