Lint cleanup.

[chaz/tar] / src / list.c

/* List a tar archive, with support routines for reading a tar archive.
   Copyright 1988,92,93,94,96,97,98,1999 Free Software Foundation, Inc.
   Written by John Gilmore, on 1985-08-26.

   This program 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; either version 2, or (at your option) any later
   version.

   This program 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 this program; if not, write to the Free Software Foundation, Inc.,
   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* Define to non-zero for forcing old ctime() instead of isotime().  */
#undef USE_OLD_CTIME

#include "system.h"
#include <quotearg.h>

#include <time.h>

#include "common.h"

#define max(a, b) ((a) < (b) ? (b) : (a))

union block *current_header;    /* points to current archive header */
struct stat current_stat;       /* stat struct corresponding */
enum archive_format current_format; /* recognized format */

static uintmax_t from_chars PARAMS ((const char *, size_t, const char *,
                                     uintmax_t, uintmax_t));

/* Table of base 64 digit values indexed by unsigned chars.
   The value is 64 for unsigned chars that are not base 64 digits.  */
static char base64_map[1 + (unsigned char) -1];

static void
base64_init (void)
{
  int i;
  memset (base64_map, 64, sizeof base64_map);
  for (i = 0; i < 64; i++)
    base64_map[(int) base_64_digits[i]] = i;
}

/*-----------------------------------.
| Main loop for reading an archive.  |
`-----------------------------------*/

void
read_and (void (*do_something) ())
{
  enum read_header status = HEADER_STILL_UNREAD;
  enum read_header prev_status;

  base64_init ();
  name_gather ();
  open_archive (ACCESS_READ);

  while (1)
    {
      prev_status = status;
      status = read_header ();
      switch (status)
        {
        case HEADER_STILL_UNREAD:
          abort ();

        case HEADER_SUCCESS:

          /* Valid header.  We should decode next field (mode) first.
             Ensure incoming names are null terminated.  */

          /* FIXME: This is a quick kludge before 1.12 goes out.  */
          current_stat.st_mtime
            = TIME_FROM_CHARS (current_header->header.mtime);

          if (!name_match (current_file_name)
              || current_stat.st_mtime < newer_mtime_option
              || excluded_name (current_file_name))
            {
              char save_typeflag;

              if (current_header->header.typeflag == GNUTYPE_VOLHDR
                  || current_header->header.typeflag == GNUTYPE_MULTIVOL
                  || current_header->header.typeflag == GNUTYPE_NAMES)
                {
                  (*do_something) ();
                  continue;
                }
              if (show_omitted_dirs_option
                  && current_header->header.typeflag == DIRTYPE)
                WARN ((0, 0, _("Omitting %s"), current_file_name));

              /* Skip past it in the archive.  */

              save_typeflag = current_header->header.typeflag;
              set_next_block_after (current_header);
              if (current_header->oldgnu_header.isextended)
                skip_extended_headers ();

              /* Skip to the next header on the archive.  */

              if (save_typeflag != DIRTYPE)
                skip_file (current_stat.st_size);
              continue;
            }

          (*do_something) ();
          continue;

        case HEADER_ZERO_BLOCK:
          if (block_number_option)
            {
              char buf[UINTMAX_STRSIZE_BOUND];
              fprintf (stdlis, _("block %s: ** Block of NULs **\n"),
                       STRINGIFY_BIGINT (current_block_ordinal (), buf));
            }

          set_next_block_after (current_header);
          status = prev_status;
          if (ignore_zeros_option)
            continue;
          break;

        case HEADER_END_OF_FILE:
          if (block_number_option)
            {
              char buf[UINTMAX_STRSIZE_BOUND];
              fprintf (stdlis, _("block %s: ** End of File **\n"),
                       STRINGIFY_BIGINT (current_block_ordinal (), buf));
            }
          break;

        case HEADER_FAILURE:
          /* If the previous header was good, tell them that we are
             skipping bad ones.  */
          set_next_block_after (current_header);
          switch (prev_status)
            {
            case HEADER_STILL_UNREAD:
              WARN ((0, 0, _("Hmm, this doesn't look like a tar archive")));
              /* Fall through.  */

            case HEADER_ZERO_BLOCK:
            case HEADER_SUCCESS:
              WARN ((0, 0, _("Skipping to next file header")));
              break;

            case HEADER_END_OF_FILE:
            case HEADER_FAILURE:
              /* We are in the middle of a cascade of errors.  */
              break;
            }
          continue;
        }
      break;
    }

  apply_delayed_set_stat ();
  close_archive ();
  names_notfound ();            /* print names not found */
}

/*---------------------------------------------.
| Print a header block, based on tar options.  |
`---------------------------------------------*/

void
list_archive (void)
{
  /* Print the header block.  */

  if (verbose_option)
    {
      if (verbose_option > 1)
        decode_header (current_header, &current_stat, &current_format, 0);
      print_header ();
    }

  if (incremental_option && current_header->header.typeflag == GNUTYPE_DUMPDIR)
    {
      off_t size;
      size_t written, check;
      union block *data_block;

      set_next_block_after (current_header);
      if (multi_volume_option)
        {
          assign_string (&save_name, current_file_name);
          save_totsize = current_stat.st_size;
        }
      for (size = current_stat.st_size; size > 0; size -= written)
        {
          if (multi_volume_option)
            save_sizeleft = size;
          data_block = find_next_block ();
          if (!data_block)
            {
              ERROR ((0, 0, _("EOF in archive file")));
              break;            /* FIXME: What happens, then?  */
            }
          written = available_space_after (data_block);
          if (written > size)
            written = size;
          errno = 0;            /* FIXME: errno should be read-only */
          check = fwrite (data_block->buffer, sizeof (char), written, stdlis);
          set_next_block_after ((union block *)
                                (data_block->buffer + written - 1));
          if (check != written)
            {
              ERROR ((0, errno, _("Only wrote %lu of %lu bytes to file %s"),
                      (unsigned long) check,
                      (unsigned long) written, current_file_name));
              skip_file (size - written);
              break;
            }
        }
      if (multi_volume_option)
        assign_string (&save_name, 0);
      fputc ('\n', stdlis);
      fflush (stdlis);
      return;

    }

  /* Skip past the header in the archive, and past any extended headers.  */

  set_next_block_after (current_header);
  if (current_header->oldgnu_header.isextended)
    skip_extended_headers ();

  if (multi_volume_option)
    assign_string (&save_name, current_file_name);

  /* Skip to the next header on the archive.  */

  skip_file (current_stat.st_size);

  if (multi_volume_option)
    assign_string (&save_name, 0);
}

/*-----------------------------------------------------------------------.
| Read a block that's supposed to be a header block.  Return its address |
| in "current_header", and if it is good, the file's size in             |
| current_stat.st_size.                                                  |
|                                                                        |
| Return 1 for success, 0 if the checksum is bad, EOF on eof, 2 for a    |
| block full of zeros (EOF marker).                                      |
|                                                                        |
| You must always set_next_block_after(current_header) to skip past the  |
| header which this routine reads.                                       |
`-----------------------------------------------------------------------*/

/* The standard BSD tar sources create the checksum by adding up the
   bytes in the header as type char.  I think the type char was unsigned
   on the PDP-11, but it's signed on the Next and Sun.  It looks like the
   sources to BSD tar were never changed to compute the checksum
   correctly, so both the Sun and Next add the bytes of the header as
   signed chars.  This doesn't cause a problem until you get a file with
   a name containing characters with the high bit set.  So read_header
   computes two checksums -- signed and unsigned.  */

enum read_header
read_header (void)
{
  size_t i;
  int unsigned_sum;             /* the POSIX one :-) */
  int signed_sum;               /* the Sun one :-( */
  int recorded_sum;
  uintmax_t parsed_sum;
  char *p;
  union block *header;
  char **longp;
  char *bp;
  union block *data_block;
  size_t size, written;
  static char *next_long_name, *next_long_link;

  while (1)
    {
      header = find_next_block ();
      current_header = header;
      if (!header)
        return HEADER_END_OF_FILE;

      unsigned_sum = 0;
      signed_sum = 0;
      p = header->buffer;
      for (i = sizeof *header; i-- != 0;)
        {
          unsigned_sum += (unsigned char) *p;
          signed_sum += signed_char (*p++);
        }

      if (unsigned_sum == 0)
        return HEADER_ZERO_BLOCK;

      /* Adjust checksum to count the "chksum" field as blanks.  */

      for (i = sizeof header->header.chksum; i-- != 0;)
        {
          unsigned_sum -= (unsigned char) header->header.chksum[i];
          signed_sum -= signed_char (header->header.chksum[i]);
        }
      unsigned_sum += ' ' * sizeof header->header.chksum;
      signed_sum += ' ' * sizeof header->header.chksum;

      parsed_sum = from_chars (header->header.chksum,
                               sizeof header->header.chksum, 0,
                               (uintmax_t) 0, (uintmax_t) TYPE_MAXIMUM (int));
      if (parsed_sum == (uintmax_t) -1)
        return HEADER_FAILURE;

      recorded_sum = parsed_sum;

      if (unsigned_sum != recorded_sum && signed_sum != recorded_sum)
        return HEADER_FAILURE;

      /* Good block.  Decode file size and return.  */

      if (header->header.typeflag == LNKTYPE)
        current_stat.st_size = 0;       /* links 0 size on tape */
      else
        current_stat.st_size = OFF_FROM_CHARS (header->header.size);

      if (header->header.typeflag == GNUTYPE_LONGNAME
          || header->header.typeflag == GNUTYPE_LONGLINK)
        {
          longp = ((header->header.typeflag == GNUTYPE_LONGNAME)
                   ? &next_long_name
                   : &next_long_link);

          set_next_block_after (header);
          if (*longp)
            free (*longp);
          size = current_stat.st_size;
          if (size != current_stat.st_size)
            FATAL_ERROR ((0, 0, _("Memory exhausted")));
          bp = *longp = xmalloc (size);

          for (; size > 0; size -= written)
            {
              data_block = find_next_block ();
              if (! data_block)
                {
                  ERROR ((0, 0, _("Unexpected EOF on archive file")));
                  break;
                }
              written = available_space_after (data_block);
              if (written > size)
                written = size;

              memcpy (bp, data_block->buffer, written);
              bp += written;
              set_next_block_after ((union block *)
                                    (data_block->buffer + written - 1));
            }

          /* Loop!  */

        }
      else
        {
          char *name;
          struct posix_header *h = &current_header->header;
          char namebuf[sizeof h->prefix + 1 + NAME_FIELD_SIZE + 1];

          name = next_long_name;
          if (! name)
            {
              /* Accept file names as specified by POSIX.1-1996
                 section 10.1.1.  */
              int posix_header = strcmp (h->magic, TMAGIC) == 0;
              char *np = namebuf;

              if (posix_header && h->prefix[0])
                {
                  memcpy (np, h->prefix, sizeof h->prefix);
                  np[sizeof h->prefix] = '\0';
                  np += strlen (np);
                  *np++ = '/';
                }
              memcpy (np, h->name, sizeof h->name);
              np[sizeof h->name] = '\0';
              name = namebuf;
            }
          assign_string (&current_file_name, name);
          if (next_long_name)
            {
              free (next_long_name);
              next_long_name = 0;
            }
          
          name = next_long_link;
          if (! name)
            {
              memcpy (namebuf, h->linkname, sizeof h->linkname);
              namebuf[sizeof h->linkname] = '\0';
              name = namebuf;
            }
          assign_string (&current_link_name, name);
          if (next_long_link)
            {
              free (next_long_link);
              next_long_link = 0;
            }

          return HEADER_SUCCESS;
        }
    }
}

/*-------------------------------------------------------------------------.
| Decode things from a file HEADER block into STAT_INFO, also setting      |
| *FORMAT_POINTER depending on the header block format.  If DO_USER_GROUP, |
| decode the user/group information (this is useful for extraction, but    |
| waste time when merely listing).                                         |
|                                                                          |
| read_header() has already decoded the checksum and length, so we don't.  |
|                                                                          |
| This routine should *not* be called twice for the same block, since the  |
| two calls might use different DO_USER_GROUP values and thus might end up |
| with different uid/gid for the two calls.  If anybody wants the uid/gid  |
| they should decode it first, and other callers should decode it without  |
| uid/gid before calling a routine, e.g. print_header, that assumes        |
| decoded data.                                                            |
`-------------------------------------------------------------------------*/

void
decode_header (union block *header, struct stat *stat_info,
               enum archive_format *format_pointer, int do_user_group)
{
  enum archive_format format;

  if (strcmp (header->header.magic, TMAGIC) == 0)
    format = POSIX_FORMAT;
  else if (strcmp (header->header.magic, OLDGNU_MAGIC) == 0)
    format = OLDGNU_FORMAT;
  else
    format = V7_FORMAT;
  *format_pointer = format;

  stat_info->st_mode = MODE_FROM_CHARS (header->header.mode);
  stat_info->st_mtime = TIME_FROM_CHARS (header->header.mtime);

  if (format == OLDGNU_FORMAT && incremental_option)
    {
      stat_info->st_atime = TIME_FROM_CHARS (header->oldgnu_header.atime);
      stat_info->st_ctime = TIME_FROM_CHARS (header->oldgnu_header.ctime);
    }

  if (format == V7_FORMAT)
    {
      stat_info->st_uid = UID_FROM_CHARS (header->header.uid);
      stat_info->st_gid = GID_FROM_CHARS (header->header.gid);
      stat_info->st_rdev = 0;
    }
  else
    {
      if (do_user_group)
        {
          /* FIXME: Decide if this should somewhat depend on -p.  */

          if (numeric_owner_option
              || !*header->header.uname
              || !uname_to_uid (header->header.uname, &stat_info->st_uid))
            stat_info->st_uid = UID_FROM_CHARS (header->header.uid);

          if (numeric_owner_option
              || !*header->header.gname
              || !gname_to_gid (header->header.gname, &stat_info->st_gid))
            stat_info->st_gid = GID_FROM_CHARS (header->header.gid);
        }
      switch (header->header.typeflag)
        {
        case BLKTYPE:
          stat_info->st_rdev
            = makedev (MAJOR_FROM_CHARS (header->header.devmajor),
                       MINOR_FROM_CHARS (header->header.devminor));
          break;

        case CHRTYPE:
          stat_info->st_rdev
            = makedev (MAJOR_FROM_CHARS (header->header.devmajor),
                       MINOR_FROM_CHARS (header->header.devminor));
          break;

        default:
          stat_info->st_rdev = 0;
        }
    }
}

/*------------------------------------------------------------------------.
| Convert buffer at WHERE0 of size DIGS from external format to uintmax_t.|
| The data is of type TYPE.  The buffer must represent a value in the     |
| range -MINUS_MINVAL through MAXVAL.                                     |
`------------------------------------------------------------------------*/

static uintmax_t
from_chars (char const *where0, size_t digs, char const *type,
            uintmax_t minus_minval, uintmax_t maxval)
{
  uintmax_t value;
  char const *where = where0;
  char const *lim = where + digs;
  int negative = 0;

  /* Accommodate buggy tar of unknown vintage, which outputs leading
     NUL if the previous field overflows.  */
  where += !*where;

  /* Accommodate older tars, which output leading spaces.  */
  for (;;)
    {
      if (where == lim)
        {
          if (type)
            ERROR ((0, 0,
                    _("Blanks in header where numeric %s value expected"),
                    type));
          return -1;
        }
      if (!ISSPACE ((unsigned char) *where))
        break;
      where++;
    }

  value = 0;
  if (ISODIGIT (*where))
    {
      do
        {
          if (value << LG_8 >> LG_8 != value)
            {
              ERROR ((0, 0,
                      _("Archive octal string `%.*s' is out of %s range"),
                      (int) digs, where0, type));
              return -1;
            }
          value = (value << LG_8) | (*where++ - '0');
        }
      while (where != lim && ISODIGIT (*where));

      /* Parse the output of older tars, which output negative values
         in two's complement octal.  This method works only if the
         type has the same number of bits as it did on the host that
         created the tar file, but that's the best we can do.  */
      if (maxval < value && value - maxval <= minus_minval)
        {
          value = minus_minval - (value - maxval);
          negative = 1;
        }
    }
  else if (*where == '-' || *where == '+')
    {
      int dig;
      negative = *where++ == '-';
      while (where != lim
             && (dig = base64_map[(unsigned char) *where]) < 64)
        {
          if (value << LG_64 >> LG_64 != value)
            {
              ERROR ((0, 0,
                      _("Archive signed base 64 string `%.*s' is out of %s range"),
                      (int) digs, where0, type));
              return -1;
            }
          value = (value << LG_64) | dig;
          where++;
        }
    }

  if (where != lim && *where && !ISSPACE ((unsigned char) *where))
    {
      if (type)
        {
          char buf[1000]; /* Big enough to represent any header.  */
          static struct quoting_options *o;

          if (!o)
            {
              o = clone_quoting_options (0);
              set_quoting_style (o, c_quoting_style);
            }

          while (where0 != lim && ! lim[-1])
            lim--;
          quotearg_buffer (buf, sizeof buf, where0, lim - where, o);
          ERROR ((0, 0,
                  _("Archive contains `%.*s' where numeric %s value expected"),
                  (int) sizeof buf, buf, type));
        }

      return -1;
    }

  if (value <= (negative ? minus_minval : maxval))
    return negative ? -value : value;

  if (type)
    {
      char minval_buf[UINTMAX_STRSIZE_BOUND + 1];
      char maxval_buf[UINTMAX_STRSIZE_BOUND];
      char value_buf[UINTMAX_STRSIZE_BOUND + 1];
      char *minval_string = STRINGIFY_BIGINT (minus_minval, minval_buf + 1);
      char *value_string = STRINGIFY_BIGINT (value, value_buf + 1);
      if (negative)
        *--value_string = '-';
      if (minus_minval)
        *--minval_string = '-';
      ERROR ((0, 0, _("Archive value %s is out of %s range %s..%s"),
              value_string, type,
              minval_string, STRINGIFY_BIGINT (maxval, maxval_buf)));
    }

  return -1;
}

gid_t
gid_from_chars (const char *p, size_t s)
{
  return from_chars (p, s, "gid_t",
                     - (uintmax_t) TYPE_MINIMUM (gid_t),
                     (uintmax_t) TYPE_MAXIMUM (gid_t));
}

major_t
major_from_chars (const char *p, size_t s)
{
  return from_chars (p, s, "major_t",
                     - (uintmax_t) TYPE_MINIMUM (major_t),
                     (uintmax_t) TYPE_MAXIMUM (major_t));
}

minor_t
minor_from_chars (const char *p, size_t s)
{
  return from_chars (p, s, "minor_t",
                     - (uintmax_t) TYPE_MINIMUM (minor_t),
                     (uintmax_t) TYPE_MAXIMUM (minor_t));
}

mode_t
mode_from_chars (const char *p, size_t s)
{
  /* Do not complain about unrecognized mode bits.  */
  unsigned u = from_chars (p, s, "mode_t",
                           - (uintmax_t) TYPE_MINIMUM (mode_t),
                           TYPE_MAXIMUM (uintmax_t));
  return ((u & TSUID ? S_ISUID : 0)
          | (u & TSGID ? S_ISGID : 0)
          | (u & TSVTX ? S_ISVTX : 0)
          | (u & TUREAD ? S_IRUSR : 0)
          | (u & TUWRITE ? S_IWUSR : 0)
          | (u & TUEXEC ? S_IXUSR : 0)
          | (u & TGREAD ? S_IRGRP : 0)
          | (u & TGWRITE ? S_IWGRP : 0)
          | (u & TGEXEC ? S_IXGRP : 0)
          | (u & TOREAD ? S_IROTH : 0)
          | (u & TOWRITE ? S_IWOTH : 0)
          | (u & TOEXEC ? S_IXOTH : 0));
}

off_t
off_from_chars (const char *p, size_t s)
{
  /* Negative offsets are not allowed in tar files, so invoke
     from_chars with minimum value 0, not TYPE_MINIMUM (off_t).  */
  return from_chars (p, s, "off_t", (uintmax_t) 0,
                     (uintmax_t) TYPE_MAXIMUM (off_t));
}

size_t
size_from_chars (const char *p, size_t s)
{
  return from_chars (p, s, "size_t", (uintmax_t) 0, 
                     (uintmax_t) TYPE_MAXIMUM (size_t));
}

time_t
time_from_chars (const char *p, size_t s)
{
  return from_chars (p, s, "time_t",
                     - (uintmax_t) TYPE_MINIMUM (time_t),
                     (uintmax_t) TYPE_MAXIMUM (time_t));
}

uid_t
uid_from_chars (const char *p, size_t s)
{
  return from_chars (p, s, "uid_t",
                     - (uintmax_t) TYPE_MINIMUM (uid_t),
                     (uintmax_t) TYPE_MAXIMUM (uid_t));
}

uintmax_t
uintmax_from_chars (const char *p, size_t s)
{
  return from_chars (p, s, "uintmax_t", (uintmax_t) 0,
                     TYPE_MAXIMUM (uintmax_t));
}


/*----------------------------------------------------------------------.
| Format O as a null-terminated decimal string into BUF _backwards_;    |
| return pointer to start of result.                                    |
`----------------------------------------------------------------------*/
char *
stringify_uintmax_t_backwards (uintmax_t o, char *buf)
{
  *--buf = '\0';
  do
    *--buf = '0' + (int) (o % 10);
  while ((o /= 10) != 0);
  return buf;
}

#if !USE_OLD_CTIME

/*-------------------------------------------.
| Return the time formatted along ISO 8601.  |
`-------------------------------------------*/

/* Also, see http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html.  */

static char const *
isotime (time_t time)
{
  static char buffer[max (UINTMAX_STRSIZE_BOUND + 1,
                          INT_STRLEN_BOUND (int) + 16)];
  struct tm *tm = localtime (&time);
  if (tm)
    {
      sprintf (buffer, "%04d-%02d-%02d %02d:%02d:%02d",
               tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
               tm->tm_hour, tm->tm_min, tm->tm_sec);
      return buffer;
    }
  else
    {
      /* The time stamp cannot be broken down, most likely because it
         is out of range.  Convert it as an integer,
         right-adjusted in a field with the same width as the usual
         19-byte 4-year ISO time format.  */
      uintmax_t abstime = time < 0 ? - (uintmax_t) time : time;
      char *p = stringify_uintmax_t_backwards (abstime,
                                               buffer + sizeof buffer);
      if (time < 0)
        *--p = '-';
      while (buffer + sizeof buffer - 19 - 1 < p)
        *--p = ' ';
      return p;
    }
}

#endif /* not USE_OLD_CTIME */

/*-------------------------------------------------------------------------.
| Decode MODE from its binary form in a stat structure, and encode it into |
| a 9 characters string STRING, terminated with a NUL.                     |
`-------------------------------------------------------------------------*/

static void
decode_mode (mode_t mode, char *string)
{
  *string++ = mode & S_IRUSR ? 'r' : '-';
  *string++ = mode & S_IWUSR ? 'w' : '-';
  *string++ = (mode & S_ISUID
               ? (mode & S_IXUSR ? 's' : 'S')
               : (mode & S_IXUSR ? 'x' : '-'));
  *string++ = mode & S_IRGRP ? 'r' : '-';
  *string++ = mode & S_IWGRP ? 'w' : '-';
  *string++ = (mode & S_ISGID
               ? (mode & S_IXGRP ? 's' : 'S')
               : (mode & S_IXGRP ? 'x' : '-'));
  *string++ = mode & S_IROTH ? 'r' : '-';
  *string++ = mode & S_IWOTH ? 'w' : '-';
  *string++ = (mode & S_ISVTX
               ? (mode & S_IXOTH ? 't' : 'T')
               : (mode & S_IXOTH ? 'x' : '-'));
  *string = '\0';
}

/*-------------------------------------------------------------------------.
| Actually print it.                                                       |
|                                                                          |
| Plain and fancy file header block logging.  Non-verbose just prints the  |
| name, e.g. for "tar t" or "tar x".  This should just contain file names, |
| so it can be fed back into tar with xargs or the "-T" option.  The       |
| verbose option can give a bunch of info, one line per file.  I doubt     |
| anybody tries to parse its format, or if they do, they shouldn't.  Unix  |
| tar is pretty random here anyway.                                        |
`-------------------------------------------------------------------------*/

/* FIXME: Note that print_header uses the globals HEAD, HSTAT, and
   HEAD_STANDARD, which must be set up in advance.  Not very clean...  */

/* UGSWIDTH starts with 18, so with user and group names <= 8 chars, the
   columns never shift during the listing.  */
#define UGSWIDTH 18
static int ugswidth = UGSWIDTH; /* maximum width encountered so far */

/* DATEWIDTH is the number of columns taken by the date and time fields.  */
#if USE_OLD_CDATE
# define DATEWIDTH 19
#else
# define DATEWIDTH 18
#endif

void
print_header (void)
{
  char modes[11];
  char const *time_stamp;
  /* These hold formatted ints.  */
  char uform[UINTMAX_STRSIZE_BOUND], gform[UINTMAX_STRSIZE_BOUND];
  char *user, *group;
  char size[2 * UINTMAX_STRSIZE_BOUND];
                                /* holds formatted size or major,minor */
  char uintbuf[UINTMAX_STRSIZE_BOUND];
  time_t longie;                /* to make ctime() call portable */
  int pad;
  char *name;

  if (block_number_option)
    {
      char buf[UINTMAX_STRSIZE_BOUND];
      fprintf (stdlis, _("block %s: "),
               STRINGIFY_BIGINT (current_block_ordinal (), buf));
    }

  if (verbose_option <= 1)
    {
      /* Just the fax, mam.  */

      char *quoted_name = quote_copy_string (current_file_name);

      if (quoted_name)
        {
          fprintf (stdlis, "%s\n", quoted_name);
          free (quoted_name);
        }
      else
        fprintf (stdlis, "%s\n", current_file_name);
    }
  else
    {
      /* File type and modes.  */

      modes[0] = '?';
      switch (current_header->header.typeflag)
        {
        case GNUTYPE_VOLHDR:
          modes[0] = 'V';
          break;

        case GNUTYPE_MULTIVOL:
          modes[0] = 'M';
          break;

        case GNUTYPE_NAMES:
          modes[0] = 'N';
          break;

        case GNUTYPE_LONGNAME:
        case GNUTYPE_LONGLINK:
          ERROR ((0, 0, _("Visible longname error")));
          break;

        case GNUTYPE_SPARSE:
        case REGTYPE:
        case AREGTYPE:
        case LNKTYPE:
          modes[0] = '-';
          if (current_file_name[strlen (current_file_name) - 1] == '/')
            modes[0] = 'd';
          break;
        case GNUTYPE_DUMPDIR:
          modes[0] = 'd';
          break;
        case DIRTYPE:
          modes[0] = 'd';
          break;
        case SYMTYPE:
          modes[0] = 'l';
          break;
        case BLKTYPE:
          modes[0] = 'b';
          break;
        case CHRTYPE:
          modes[0] = 'c';
          break;
        case FIFOTYPE:
          modes[0] = 'p';
          break;
        case CONTTYPE:
          modes[0] = 'C';
          break;
        }

      decode_mode (current_stat.st_mode, modes + 1);

      /* Time stamp.  */

      longie = current_stat.st_mtime;
#if USE_OLD_CTIME
      {
        char *ct = ctime (&longie);
        if (ct)
          {
            time_stamp = ct + 4;
            for (ct += 16; ct[4] != '\n'; ct++)
              ct[0] = ct[4];
            ct[0] = '\0';
          }
        else
          time_stamp = "??? ?? ??:?? ????";
      }
#else
      time_stamp = isotime (longie);
#endif

      /* User and group names.  */

      if (*current_header->header.uname && current_format != V7_FORMAT
          && !numeric_owner_option)
        user = current_header->header.uname;
      else
        user = STRINGIFY_BIGINT (UINTMAX_FROM_CHARS
                                 (current_header->header.uid),
                                 uform);

      if (*current_header->header.gname && current_format != V7_FORMAT
          && !numeric_owner_option)
        group = current_header->header.gname;
      else
        group = STRINGIFY_BIGINT (UINTMAX_FROM_CHARS
                                  (current_header->header.gid),
                                  gform);

      /* Format the file size or major/minor device numbers.  */

      switch (current_header->header.typeflag)
        {
        case CHRTYPE:
        case BLKTYPE:
          strcpy (size,
                  STRINGIFY_BIGINT (major (current_stat.st_rdev), uintbuf));
          strcat (size, ",");
          strcat (size,
                  STRINGIFY_BIGINT (minor (current_stat.st_rdev), uintbuf));
          break;
        case GNUTYPE_SPARSE:
          strcpy (size,
                  STRINGIFY_BIGINT
                  (UINTMAX_FROM_CHARS (current_header->oldgnu_header.realsize),
                   uintbuf));
          break;
        default:
          strcpy (size, STRINGIFY_BIGINT (current_stat.st_size, uintbuf));
          break;
        }

      /* Figure out padding and print the whole line.  */

      pad = strlen (user) + strlen (group) + strlen (size) + 1;
      if (pad > ugswidth)
        ugswidth = pad;

      fprintf (stdlis, "%s %s/%s %*s%s %s",
               modes, user, group, ugswidth - pad, "", size, time_stamp);

      name = quote_copy_string (current_file_name);
      if (name)
        {
          fprintf (stdlis, " %s", name);
          free (name);
        }
      else
        fprintf (stdlis, " %s", current_file_name);

      switch (current_header->header.typeflag)
        {
        case SYMTYPE:
          name = quote_copy_string (current_link_name);
          if (name)
            {
              fprintf (stdlis, " -> %s\n", name);
              free (name);
            }
          else
            fprintf (stdlis, " -> %s\n", current_link_name);
          break;

        case LNKTYPE:
          name = quote_copy_string (current_link_name);
          if (name)
            {
              fprintf (stdlis, _(" link to %s\n"), name);
              free (name);
            }
          else
            fprintf (stdlis, _(" link to %s\n"), current_link_name);
          break;

        default:
          fprintf (stdlis, _(" unknown file type `%c'\n"),
                   current_header->header.typeflag);
          break;

        case AREGTYPE:
        case REGTYPE:
        case GNUTYPE_SPARSE:
        case CHRTYPE:
        case BLKTYPE:
        case DIRTYPE:
        case FIFOTYPE:
        case CONTTYPE:
        case GNUTYPE_DUMPDIR:
          putc ('\n', stdlis);
          break;

        case GNUTYPE_VOLHDR:
          fprintf (stdlis, _("--Volume Header--\n"));
          break;

        case GNUTYPE_MULTIVOL:
          strcpy (size,
                  STRINGIFY_BIGINT
                  (UINTMAX_FROM_CHARS (current_header->oldgnu_header.offset),
                   uintbuf));
          fprintf (stdlis, _("--Continued at byte %s--\n"), size);
          break;

        case GNUTYPE_NAMES:
          fprintf (stdlis, _("--Mangled file names--\n"));
          break;
        }
    }
  fflush (stdlis);
}

/*--------------------------------------------------------------.
| Print a similar line when we make a directory automatically.  |
`--------------------------------------------------------------*/

void
print_for_mkdir (char *pathname, int length, mode_t mode)
{
  char modes[11];
  char *name;

  if (verbose_option > 1)
    {
      /* File type and modes.  */

      modes[0] = 'd';
      decode_mode (mode, modes + 1);

      if (block_number_option)
        {
          char buf[UINTMAX_STRSIZE_BOUND];
          fprintf (stdlis, _("block %s: "),
                   STRINGIFY_BIGINT (current_block_ordinal (), buf));
        }
      name = quote_copy_string (pathname);
      if (name)
        {
          fprintf (stdlis, "%s %*s %.*s\n", modes, ugswidth + DATEWIDTH,
                   _("Creating directory:"), length, name);
          free (name);
        }
      else
        fprintf (stdlis, "%s %*s %.*s\n", modes, ugswidth + DATEWIDTH,
                 _("Creating directory:"), length, pathname);
    }
}

/*--------------------------------------------------------.
| Skip over SIZE bytes of data in blocks in the archive.  |
`--------------------------------------------------------*/

void
skip_file (off_t size)
{
  union block *x;

  if (multi_volume_option)
    {
      save_totsize = size;
      save_sizeleft = size;
    }

  while (size > 0)
    {
      x = find_next_block ();
      if (! x)
        FATAL_ERROR ((0, 0, _("Unexpected EOF on archive file")));

      set_next_block_after (x);
      size -= BLOCKSIZE;
      if (multi_volume_option)
        save_sizeleft -= BLOCKSIZE;
    }
}

/*---.
| ?  |
`---*/

void
skip_extended_headers (void)
{
  union block *exhdr;

  do
    {
      exhdr = find_next_block ();
      if (!exhdr)
        FATAL_ERROR ((0, 0, _("Unexpected EOF on archive file")));
      set_next_block_after (exhdr);
    }
  while (exhdr->sparse_header.isextended);
}