[xemacs-hg @ 2001-09-20 06:28:42 by ben] The great integral types renaming. The purpose of this is to rationalize the names used for various integral types, so that they match their intended uses and follow consist conventions, and eliminate types that were not semantically different from each other. The conventions are: -- All integral types that measure quantities of anything are signed. Some people disagree vociferously with this, but their arguments are mostly theoretical, and are vastly outweighed by the practical headaches of mixing signed and unsigned values, and more importantly by the far increased likelihood of inadvertent bugs: Because of the broken "viral" nature of unsigned quantities in C (operations involving mixed signed/unsigned are done unsigned, when exactly the opposite is nearly always wanted), even a single error in declaring a quantity unsigned that should be signed, or even the even more subtle error of comparing signed and unsigned values and forgetting the necessary cast, can be catastrophic, as comparisons will yield wrong results. -Wsign-compare is turned on specifically to catch this, but this tends to result in a great number of warnings when mixing signed and unsigned, and the casts are annoying. More has been written on this elsewhere. -- All such quantity types just mentioned boil down to EMACS_INT, which is 32 bits on 32-bit machines and 64 bits on 64-bit machines. This is guaranteed to be the same size as Lisp objects of type `int', and (as far as I can tell) of size_t (unsigned!) and ssize_t. The only type below that is not an EMACS_INT is Hashcode, which is an unsigned value of the same size as EMACS_INT. -- Type names should be relatively short (no more than 10 characters or so), with the first letter capitalized and no underscores if they can at all be avoided. -- "count" == a zero-based measurement of some quantity. Includes sizes, offsets, and indexes. -- "bpos" == a one-based measurement of a position in a buffer. "Charbpos" and "Bytebpos" count text in the buffer, rather than bytes in memory; thus Bytebpos does not directly correspond to the memory representation. Use "Membpos" for this. -- "Char" refers to internal-format characters, not to the C type "char", which is really a byte. -- For the actual name changes, see the script below. I ran the following script to do the conversion. (NOTE: This script is idempotent. You can safely run it multiple times and it will not screw up previous results -- in fact, it will do nothing if nothing has changed. Thus, it can be run repeatedly as necessary to handle patches coming in from old workspaces, or old branches.) There are two tags, just before and just after the change: `pre-integral-type-rename' and `post-integral-type-rename'. When merging code from the main trunk into a branch, the best thing to do is first merge up to `pre-integral-type-rename', then apply the script and associated changes, then merge from `post-integral-type-change' to the present. (Alternatively, just do the merging in one operation; but you may then have a lot of conflicts needing to be resolved by hand.) Script `fixtypes.sh' follows: ----------------------------------- cut ------------------------------------ files="*.[ch] s/*.h m/*.h config.h.in ../configure.in Makefile.in.in ../lib-src/*.[ch] ../lwlib/*.[ch]" gr Memory_Count Bytecount $files gr Lstream_Data_Count Bytecount $files gr Element_Count Elemcount $files gr Hash_Code Hashcode $files gr extcount bytecount $files gr bufpos charbpos $files gr bytind bytebpos $files gr memind membpos $files gr bufbyte intbyte $files gr Extcount Bytecount $files gr Bufpos Charbpos $files gr Bytind Bytebpos $files gr Memind Membpos $files gr Bufbyte Intbyte $files gr EXTCOUNT BYTECOUNT $files gr BUFPOS CHARBPOS $files gr BYTIND BYTEBPOS $files gr MEMIND MEMBPOS $files gr BUFBYTE INTBYTE $files gr MEMORY_COUNT BYTECOUNT $files gr LSTREAM_DATA_COUNT BYTECOUNT $files gr ELEMENT_COUNT ELEMCOUNT $files gr HASH_CODE HASHCODE $files ----------------------------------- cut ------------------------------------ `fixtypes.sh' is a Bourne-shell script; it uses 'gr': ----------------------------------- cut ------------------------------------ #!/bin/sh # Usage is like this: # gr FROM TO FILES ... # globally replace FROM with TO in FILES. FROM and TO are regular expressions. # backup files are stored in the `backup' directory. from="$1" to="$2" shift 2 echo ${1+"$@"} | xargs global-replace "s/$from/$to/g" ----------------------------------- cut ------------------------------------ `gr' in turn uses a Perl script to do its real work, `global-replace', which follows: ----------------------------------- cut ------------------------------------ : #-*- Perl -*- ### global-modify --- modify the contents of a file by a Perl expression ## Copyright (C) 1999 Martin Buchholz. ## Copyright (C) 2001 Ben Wing. ## Authors: Martin Buchholz <martin@xemacs.org>, Ben Wing <ben@xemacs.org> ## Maintainer: Ben Wing <ben@xemacs.org> ## Current Version: 1.0, May 5, 2001 # 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 XEmacs; see the file COPYING. If not, write to the Free # Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA # 02111-1307, USA. eval 'exec perl -w -S $0 ${1+"$@"}' if 0; use strict; use FileHandle; use Carp; use Getopt::Long; use File::Basename; (my $myName = $0) =~ s@.*/@@; my $usage=" Usage: $myName [--help] [--backup-dir=DIR] [--line-mode] [--hunk-mode] PERLEXPR FILE ... Globally modify a file, either line by line or in one big hunk. Typical usage is like this: [with GNU print, GNU xargs: guaranteed to handle spaces, quotes, etc. in file names] find . -name '*.[ch]' -print0 | xargs -0 $0 's/\bCONST\b/const/g'\n [with non-GNU print, xargs] find . -name '*.[ch]' -print | xargs $0 's/\bCONST\b/const/g'\n The file is read in, either line by line (with --line-mode specified) or in one big hunk (with --hunk-mode specified; it's the default), and the Perl expression is then evalled with \$_ set to the line or hunk of text, including the terminating newline if there is one. It should destructively modify the value there, storing the changed result in \$_. Files in which any modifications are made are backed up to the directory specified using --backup-dir, or to `backup' by default. To disable this, use --backup-dir= with no argument. Hunk mode is the default because it is MUCH MUCH faster than line-by-line. Use line-by-line only when it matters, e.g. you want to do a replacement only once per line (the default without the `g' argument). Conversely, when using hunk mode, *ALWAYS* use `g'; otherwise, you will only make one replacement in the entire file! "; my %options = (); $Getopt::Long::ignorecase = 0; &GetOptions ( \%options, 'help', 'backup-dir=s', 'line-mode', 'hunk-mode', ); die $usage if $options{"help"} or @ARGV <= 1; my $code = shift; die $usage if grep (-d || ! -w, @ARGV); sub SafeOpen { open ((my $fh = new FileHandle), $_[0]); confess "Can't open $_[0]: $!" if ! defined $fh; return $fh; } sub SafeClose { close $_[0] or confess "Can't close $_[0]: $!"; } sub FileContents { my $fh = SafeOpen ("< $_[0]"); my $olddollarslash = $/; local $/ = undef; my $contents = <$fh>; $/ = $olddollarslash; return $contents; } sub WriteStringToFile { my $fh = SafeOpen ("> $_[0]"); binmode $fh; print $fh $_[1] or confess "$_[0]: $!\n"; SafeClose $fh; } foreach my $file (@ARGV) { my $changed_p = 0; my $new_contents = ""; if ($options{"line-mode"}) { my $fh = SafeOpen $file; while (<$fh>) { my $save_line = $_; eval $code; $changed_p = 1 if $save_line ne $_; $new_contents .= $_; } } else { my $orig_contents = $_ = FileContents $file; eval $code; if ($_ ne $orig_contents) { $changed_p = 1; $new_contents = $_; } } if ($changed_p) { my $backdir = $options{"backup-dir"}; $backdir = "backup" if !defined ($backdir); if ($backdir) { my ($name, $path, $suffix) = fileparse ($file, ""); my $backfulldir = $path . $backdir; my $backfile = "$backfulldir/$name"; mkdir $backfulldir, 0755 unless -d $backfulldir; print "modifying $file (original saved in $backfile)\n"; rename $file, $backfile; } WriteStringToFile ($file, $new_contents); } } ----------------------------------- cut ------------------------------------ In addition to those programs, I needed to fix up a few other things, particularly relating to the duplicate definitions of types, now that some types merged with others. Specifically: 1. in lisp.h, removed duplicate declarations of Bytecount. The changed code should now look like this: (In each code snippet below, the first and last lines are the same as the original, as are all lines outside of those lines. That allows you to locate the section to be replaced, and replace the stuff in that section, verifying that there isn't anything new added that would need to be kept.) --------------------------------- snip ------------------------------------- /* Counts of bytes or chars */ typedef EMACS_INT Bytecount; typedef EMACS_INT Charcount; /* Counts of elements */ typedef EMACS_INT Elemcount; /* Hash codes */ typedef unsigned long Hashcode; /* ------------------------ dynamic arrays ------------------- */ --------------------------------- snip ------------------------------------- 2. in lstream.h, removed duplicate declaration of Bytecount. Rewrote the comment about this type. The changed code should now look like this: --------------------------------- snip ------------------------------------- #endif /* The have been some arguments over the what the type should be that specifies a count of bytes in a data block to be written out or read in, using Lstream_read(), Lstream_write(), and related functions. Originally it was long, which worked fine; Martin "corrected" these to size_t and ssize_t on the grounds that this is theoretically cleaner and is in keeping with the C standards. Unfortunately, this practice is horribly error-prone due to design flaws in the way that mixed signed/unsigned arithmetic happens. In fact, by doing this change, Martin introduced a subtle but fatal error that caused the operation of sending large mail messages to the SMTP server under Windows to fail. By putting all values back to be signed, avoiding any signed/unsigned mixing, the bug immediately went away. The type then in use was Lstream_Data_Count, so that it be reverted cleanly if a vote came to that. Now it is Bytecount. Some earlier comments about why the type must be signed: This MUST BE SIGNED, since it also is used in functions that return the number of bytes actually read to or written from in an operation, and these functions can return -1 to signal error. Note that the standard Unix read() and write() functions define the count going in as a size_t, which is UNSIGNED, and the count going out as an ssize_t, which is SIGNED. This is a horrible design flaw. Not only is it highly likely to lead to logic errors when a -1 gets interpreted as a large positive number, but operations are bound to fail in all sorts of horrible ways when a number in the upper-half of the size_t range is passed in -- this number is unrepresentable as an ssize_t, so code that checks to see how many bytes are actually written (which is mandatory if you are dealing with certain types of devices) will get completely screwed up. --ben */ typedef enum lstream_buffering --------------------------------- snip ------------------------------------- 3. in dumper.c, there are four places, all inside of switch() statements, where XD_BYTECOUNT appears twice as a case tag. In each case, the two case blocks contain identical code, and you should *REMOVE THE SECOND* and leave the first.

/*
 * Copyright (c) 2000, Red Hat, Inc.
 *
 *     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 of the License, or
 *     (at your option) any later version.
 *
 *     A copy of the GNU General Public License can be found at
 *     http://www.gnu.org/
 *
 * Written by DJ Delorie <dj@cygnus.com>
 *
 */

/* Built-in tar functionality.  See tar.h for usage. */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>

#include "win32.h"
#include <zlib.h>
#include "tar.h"
#include "mkdir.h"
#include "log.h"

#include "port.h"

#if defined(CYGWIN) || defined(MINGW)
#define FACTOR (0x19db1ded53ea710LL)
#define NSPERSEC 10000000LL
#else
__int64 FACTOR=0x19db1ded53ea710L;
__int64 NSPERSEC=10000000L;
#endif
#define SYMLINK_COOKIE "!<symlink>"

typedef struct {
  char name[100];               /*   0 */
  char mode[8];                 /* 100 */
  char uid[8];                  /* 108 */
  char gid[8];                  /* 116 */
  char size[12];                /* 124 */
  char mtime[12];               /* 136 */
  char chksum[8];               /* 148 */
  char typeflag;                /* 156 */
  char linkname[100];           /* 157 */
  char magic[6];                /* 257 */
  char version[2];              /* 263 */
  char uname[32];               /* 265 */
  char gname[32];               /* 297 */
  char devmajor[8];             /* 329 */
  char devminor[8];             /* 337 */
  char prefix[155];             /* 345 */
  char junk[12];		/* 500 */
} tar_header_type;

typedef struct tar_map_result_type_s {
  struct tar_map_result_type_s *next;
  char *stored_name;
  char *mapped_name;
} tar_map_result_type;

static tar_map_result_type *tar_map_result = 0;

static int err;

static char file_name[_MAX_PATH+512];
static char have_longname = 0;
static int  file_length;

static tar_header_type tar_header;
static char buf[512];

static int _tar_file_size = 0;
int _tar_verbose = 0;
FILE * _tar_vfile = 0;
#define vp if (_tar_verbose) fprintf
#define vp2 if (_tar_verbose>1) fprintf

static gzFile g = 0;

static char *
xstrdup (char *c)
{
  char *r = (char *) malloc (strlen (c) + 1);
  if (!r)
    exit_setup (1);
  strcpy (r, c);
  return r;
}

int
tar_open (char *pathname)
{
  struct stat s;
  if (_tar_vfile == 0)
    _tar_vfile = stderr;

  vp2 (_tar_vfile, "tar: open `%s'\n", pathname);
  if (stat (pathname, &s) < 0)
    return 1;
  _tar_file_size = s.st_size;

  g = gzopen (pathname, "rb");
  if (sizeof (tar_header) != 512)
    {
      /* drastic, but important */
      fprintf (stderr, "compilation error: tar header struct not 512"
	       " bytes (it's %d)\n", sizeof (tar_header));
      exit_setup (1);
    }
  err = 0;
  return g ? 0 : 1;
}

/* For some reason the cygwin version uses a function that is not in
   the original source. We duplicate it here - although this does mean
   revealing some internals. */
extern "C" {
  z_off_t ZEXPORT tar_gzctell (gzFile file);
  typedef struct gz_stream {
    z_stream stream;
    int      z_err;   /* error code for last stream operation */
    int      z_eof;   /* set if end of input file */
    FILE     *file;   /* .gz file */
    Byte     *inbuf;  /* input buffer */
    Byte     *outbuf; /* output buffer */
    uLong    crc;     /* crc32 of uncompressed data */
    char     *msg;    /* error message */
    char     *path;   /* path name for debugging only */
    int      transparent; /* 1 if input file is not a .gz file */
    char     mode;    /* 'w' or 'r' */
    long     startpos; /* start of compressed data in file (header skipped) */
  } gz_stream;
};

z_off_t ZEXPORT tar_gzctell (gzFile file)
{
    gz_stream *s = (gz_stream *)file;
    return ftell(s->file);
}

int
tar_ftell ()
{
  return tar_gzctell (g);
}

static void
skip_file ()
{
  while (file_length > 0)
    {
      gzread (g, buf, 512);
      file_length -= 512;
    }
}

char *
tar_next_file ()
{
  int r, n;
  char *c;
  r = gzread (g, &tar_header, 512);

  /* See if we're at end of file */
  if (r != 512)
    return 0;

  /* See if the header is all zeros (i.e. last block) */
  n = 0;
  for (r = 512/sizeof (int); r; r--)
    n |= ((int *)&tar_header)[r-1];
  if (n == 0)
    return 0;

  if (!have_longname && tar_header.typeflag != 'L')
    {
      memcpy (file_name, tar_header.name, 100);
      file_name[100] = 0;
    }

  sscanf (tar_header.size, "%o", &file_length);

  vp2 (_tar_vfile, "%c %9d %s\n", tar_header.typeflag, file_length, file_name);

  switch (tar_header.typeflag)
    {
    case 'L': /* GNU tar long name extension */
      if (file_length > _MAX_PATH)
	{
	  skip_file ();
	  fprintf (stderr, "error: long file name exceeds %d characters\n",
		   _MAX_PATH);
	  err ++;
	  gzread (g, &tar_header, 512);
	  sscanf (tar_header.size, "%o", &file_length);
	  skip_file ();
	  return tar_next_file ();
	}
      c = file_name;
      while (file_length > 0)
	{
	  int need = file_length > 512 ? 512 : file_length;
	  if (gzread (g, buf, 512) < 512)
	    return 0;
	  memcpy (c, buf, need);
	  c += need;
	  file_length -= need;
	}
      *c = 0;
      have_longname = 1;
      return tar_next_file ();

    case '3': /* char */
    case '4': /* block */
    case '6': /* fifo */
      fprintf (stderr, "warning: not extracting special file %s\n",
	       file_name);
      err ++;
      return tar_next_file ();

    case '0': /* regular file */
    case 0: /* regular file also */
    case '2': /* symbolic link */
    case '5': /* directory */
    case '7': /* contiguous file */
      return file_name;

    case '1': /* hard link, we just copy */
      return file_name;

    default:
      fprintf (stderr, "error: unknown (or unsupported) file type `%c'\n",
	       tar_header.typeflag);
      err ++;
      skip_file ();
      return tar_next_file ();
    }
}

static void
fix_time_stamp (char *path)
{
  int mtime;
#if defined(CYGWIN) || defined(MINGW)
  long long ftimev;
#else
  __int64 ftimev;
#endif
  FILETIME ftime;
  HANDLE h;

  sscanf (tar_header.mtime, "%o", &mtime);
  ftimev = mtime * NSPERSEC + FACTOR;
  ftime.dwHighDateTime = ftimev >> 32;
  ftime.dwLowDateTime = ftimev;
  h = CreateFileA (path, GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE,
		   0, OPEN_EXISTING,
		   FILE_ATTRIBUTE_NORMAL | FILE_FLAG_BACKUP_SEMANTICS, 0);
  if (h)
    {
      SetFileTime (h, 0, 0, &ftime);
      CloseHandle (h);
    }
}

static FILE *
common_fopen (char *path)
{
  FILE *out;
  out = fopen (path, "wb");
  if (!out)
    {
      /* maybe we need to create a directory */
      if (mkdir_p (0, path))
	{
	  skip_file ();
	  return 0;
	}
      out = fopen (path, "wb");
    }
  if (!out)
    {
      fprintf (stderr, "unable to write to file %s\n", path);
      perror ("The error was");
      skip_file ();
      return 0;
    }
  return out;
}

static void
prepare_for_file (char *path)
{
  DWORD w;
  mkdir_p (0, path);

  w = GetFileAttributes (path);
  if (w != 0xffffffff && w & FILE_ATTRIBUTE_DIRECTORY)
    {
      char *tmp = (char *) malloc (strlen (path) + 10);
      int i = 0;
      do {
	i++;
	sprintf (tmp, "%s.old-%d", path, i);
      } while (GetFileAttributes (tmp) != 0xffffffff);
      fprintf (stderr, "warning: moving directory \"%s\" out of the way.\n", path);
      MoveFile (path, tmp);
      free (tmp);
    }

  DeleteFileA (path);
}

int
tar_read_file (char *path)
{
  FILE *out, *copy;
  HANDLE h;
  DWORD w;
  int got;
  tar_map_result_type *tmr;

  switch (tar_header.typeflag)
    {
    case '0':	/* regular files */
    case 0:
    case '7':
      vp (_tar_vfile, "F %s\n", path);
      prepare_for_file (path);
      out = common_fopen (path);
      if (!out)
	return 1;

      while (file_length > 0)
	{
	  int put;
	  int want = file_length > 512 ? 512 : file_length;
	  got = gzread (g, buf, 512);
	  if (got < 512)
	    {
	      fprintf (stderr, "tar: unexpected end of file reading %s\n", path);
	      fclose (out);
	      remove (path);
	      return 1;
	    }
	  put = fwrite (buf, 1, want, out);
	  if (put < want)
	    {
	      fprintf (stderr, "tar: out of disk space writing %s\n", path);
	      fclose (out);
	      remove (path);
	      skip_file ();
	      return 1;
	    }
	  file_length -= want;
	}
      fclose (out);

      fix_time_stamp (path);

      /* we need this to do hard links below */
      tmr = (tar_map_result_type *) malloc (sizeof (tar_map_result_type));
      tmr->next = tar_map_result;
      tmr->stored_name = xstrdup (file_name);
      tmr->mapped_name = xstrdup (path);
      tar_map_result = tmr;

      return 0;

    case '1':	/* hard links; we just copy */
      for (tmr = tar_map_result; tmr; tmr=tmr->next)
	if (strcmp (tmr->stored_name, tar_header.linkname) == 0)
	  break;
      if (!tmr)
	{
	  fprintf (stderr, "tar: can't find %s to link %s to\n",
		   tar_header.linkname, path);
	  return 1;
	}
      vp (_tar_vfile, "H %s <- %s\n", path, tmr->mapped_name);
      prepare_for_file (path);
      copy = fopen (tmr->mapped_name, "rb");
      if (!copy)
	{
	  fprintf (stderr, "tar: unable to read %s\n", tmr->mapped_name);
	  return 1;
	}
      out = common_fopen (path);
      if (!out)
	return 1;

      while ((got = fread (buf, 1, 512, copy)) > 0)
	{
	  int put = fwrite (buf, 1, got, out);
	  if (put < got)
	    {
	      fprintf (stderr, "tar: out of disk space writing %s\n", path);
	      fclose (out);
	      fclose (copy);
	      remove (path);
	      return 1;
	    }
	}
      fclose (out);
      fclose (copy);

      fix_time_stamp (path);
      return 0;

    case '5':	/* directories */
      vp (_tar_vfile, "D %s\n", path);
      while (path[0] && path[strlen (path)-1] == '/')
	path[strlen (path) - 1] = 0;
      return mkdir_p (1, path);


    case '2':	/* symbolic links */
      vp (_tar_vfile, "L %s -> %s\n", path, tar_header.linkname);
      prepare_for_file (path);
      h = CreateFileA (path, GENERIC_WRITE, 0, 0, CREATE_NEW,
		      FILE_ATTRIBUTE_NORMAL, 0);
      if (h == INVALID_HANDLE_VALUE)
	{
	  fprintf (stderr, "error: unable to create symlink \"%s\" -> \"%s\"\n",
		   path, tar_header.linkname);
	  return 1;
	}
      strcpy (buf, SYMLINK_COOKIE);
      strcat (buf, tar_header.linkname);
      if (WriteFile (h, buf, strlen (buf) + 1, &w, NULL))
	{
	  CloseHandle (h);
	  SetFileAttributesA (path, FILE_ATTRIBUTE_SYSTEM);
	  return 0;
	}
      CloseHandle (h);
      fprintf (stderr, "error: unable to write symlink \"%s\"\n", path);
      DeleteFileA (path);
      return 1;
    }

  return 0;
}

int
tar_close ()
{
#if 0
  while (tar_map_result)
    {
      tar_map_result_type *t = tar_map_result->next;
      free (tar_map_result->stored_name);
      free (tar_map_result->mapped_name);
      free (tar_map_result);
      tar_map_result = t;
    }
#endif
  tar_map_result = 0;

  if (gzclose (g))
    err ++;
  return err; /* includes errors for skipped files, etc */
}

typedef struct {
  char *from;
  int from_len;
  char *to;
  int to_len;
} map_type;

static map_type *map;
static int nmaps;

int
tar_auto (char *pathname, char **maplist)
{
  char *c;
  int errcount = 0;
  int i, j;
  map_type mtemp;
  char newname[_MAX_PATH+512];
  static char twiddles[] = "|\b/\b-\b\\\b";
  int t = 0;

  for (nmaps=0; maplist[nmaps*2]; nmaps++) ;
  map = (map_type *) malloc ((nmaps+1) * sizeof (map_type));
  for (nmaps=0; maplist[nmaps*2]; nmaps++)
    {
      map[nmaps].from = maplist[nmaps*2];
      map[nmaps].from_len = strlen (maplist[nmaps*2]);
      map[nmaps].to = maplist[nmaps*2+1];
      map[nmaps].to_len = strlen (maplist[nmaps*2+1]);
    }
  /* bubble sort - expect the maps to be short */
  for (i=0; i<nmaps-1; i++)
    for (j=i+1; j<nmaps; j++)
      if (map[i].from_len < map[j].from_len)
	{
	  mtemp = map[i];
	  map[i] = map[j];
	  map[j] = mtemp;
	}

  if ((tar_open (pathname)))
    return 1;
  while ((c = tar_next_file ()))
    {
      int l = strlen (c);
      for (i=0; i<nmaps; i++)
	if (l >= map[i].from_len
	    && strncmp (c, map[i].from, map[i].from_len) == 0)
	  {
	    strcpy (newname, map[i].to);
	    strcpy (newname+map[i].to_len, c + map[i].from_len);
	    c = newname;
	    break;
	  }

      t = (t+2) % 8;
      fwrite (twiddles+t, 1, 2, stderr);

      if (tar_read_file (c))
	errcount ++;
    }
  if (tar_close ())
    errcount ++;

  fwrite (" \b", 1, 2, stderr);

  vp2 (_tar_vfile, "tar_auto returns %d\n", errcount);
  return errcount;
}