coreutils-8.25HEADcoreutils-8.25master

1 files changed, 403 insertions, 424 deletions

diff --git a/src/cat.c b/src/cat.c
index 90a73c2..8c39244 100644
--- a/src/cat.c
+++ b/src/cat.c
@@ -1,10 +1,10 @@
 /* cat -- concatenate files and print on the standard output.
-   Copyright (C) 88, 90, 91, 1995-2006 Free Software Foundation, Inc.
+   Copyright (C) 1988-2016 Free Software Foundation, Inc.
 
-   This program is free software; you can redistribute it and/or modify
+   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.
+   the Free Software Foundation, either version 3 of the License, 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
@@ -12,8 +12,7 @@
    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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 /* Differences from the Unix cat:
    * Always unbuffered, -u is ignored.
@@ -31,28 +30,22 @@
 #if HAVE_STROPTS_H
 # include <stropts.h>
 #endif
-#if HAVE_SYS_IOCTL_H
-# include <sys/ioctl.h>
-#endif
+#include <sys/ioctl.h>
 
 #include "system.h"
+#include "ioblksize.h"
 #include "error.h"
+#include "fadvise.h"
 #include "full-write.h"
-#include "getpagesize.h"
-#include "quote.h"
 #include "safe-read.h"
+#include "xfreopen.h"
 
-/* The official name of this program (e.g., no `g' prefix).  */
+/* The official name of this program (e.g., no 'g' prefix).  */
 #define PROGRAM_NAME "cat"
 
-#define AUTHORS "Torbjorn Granlund", "Richard M. Stallman"
-
-/* Undefine, to avoid warning about redefinition on some systems.  */
-#undef max
-#define max(h,i) ((h) > (i) ? (h) : (i))
-
-/* Name under which this program was invoked.  */
-char *program_name;
+#define AUTHORS \
+  proper_name_utf8 ("Torbjorn Granlund", "Torbj\303\266rn Granlund"), \
+  proper_name ("Richard M. Stallman")
 
 /* Name of input file.  May be "-".  */
 static char const *infile;
@@ -71,40 +64,44 @@ static char line_buf[LINE_COUNTER_BUF_LEN] =
     '\t', '\0'
   };
 
-/* Position in `line_buf' where printing starts.  This will not change
+/* Position in 'line_buf' where printing starts.  This will not change
    unless the number of lines is larger than 999999.  */
 static char *line_num_print = line_buf + LINE_COUNTER_BUF_LEN - 8;
 
-/* Position of the first digit in `line_buf'.  */
+/* Position of the first digit in 'line_buf'.  */
 static char *line_num_start = line_buf + LINE_COUNTER_BUF_LEN - 3;
 
-/* Position of the last digit in `line_buf'.  */
+/* Position of the last digit in 'line_buf'.  */
 static char *line_num_end = line_buf + LINE_COUNTER_BUF_LEN - 3;
 
-/* Preserves the `cat' function's local `newlines' between invocations.  */
+/* Preserves the 'cat' function's local 'newlines' between invocations.  */
 static int newlines2 = 0;
 
 void
 usage (int status)
 {
   if (status != EXIT_SUCCESS)
-    fprintf (stderr, _("Try `%s --help' for more information.\n"),
-	     program_name);
+    emit_try_help ();
   else
     {
       printf (_("\
-Usage: %s [OPTION] [FILE]...\n\
+Usage: %s [OPTION]... [FILE]...\n\
 "),
-	      program_name);
+              program_name);
+      fputs (_("\
+Concatenate FILE(s) to standard output.\n\
+"), stdout);
+
+      emit_stdin_note ();
+
       fputs (_("\
-Concatenate FILE(s), or standard input, to standard output.\n\
 \n\
   -A, --show-all           equivalent to -vET\n\
-  -b, --number-nonblank    number nonblank output lines\n\
+  -b, --number-nonblank    number nonempty output lines, overrides -n\n\
   -e                       equivalent to -vE\n\
   -E, --show-ends          display $ at end of each line\n\
   -n, --number             number all output lines\n\
-  -s, --squeeze-blank      never more than one single blank line\n\
+  -s, --squeeze-blank      suppress repeated empty output lines\n\
 "), stdout);
       fputs (_("\
   -t                       equivalent to -vT\n\
@@ -114,18 +111,14 @@ Concatenate FILE(s), or standard input, to standard output.\n\
 "), stdout);
       fputs (HELP_OPTION_DESCRIPTION, stdout);
       fputs (VERSION_OPTION_DESCRIPTION, stdout);
-      fputs (_("\
-\n\
-With no FILE, or when FILE is -, read standard input.\n\
-"), stdout);
       printf (_("\
 \n\
 Examples:\n\
   %s f - g  Output f's contents, then standard input, then g's contents.\n\
   %s        Copy standard input to standard output.\n\
 "),
-	      program_name, program_name);
-      printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
+              program_name, program_name);
+      emit_ancillary_info (PROGRAM_NAME);
     }
   exit (status);
 }
@@ -139,7 +132,7 @@ next_line_num (void)
   do
     {
       if ((*endp)++ < '9')
-	return;
+        return;
       *endp-- = '0';
     }
   while (endp >= line_num_start);
@@ -151,7 +144,7 @@ next_line_num (void)
     line_num_print--;
 }
 
-/* Plain cat.  Copies the file behind `input_desc' to STDOUT_FILENO.
+/* Plain cat.  Copies the file behind 'input_desc' to STDOUT_FILENO.
    Return true if successful.  */
 
 static bool
@@ -168,29 +161,29 @@ simple_cat (
 
   /* Loop until the end of the file.  */
 
-  for (;;)
+  while (true)
     {
       /* Read a block of input.  */
 
       n_read = safe_read (input_desc, buf, bufsize);
       if (n_read == SAFE_READ_ERROR)
-	{
-	  error (0, errno, "%s", infile);
-	  return false;
-	}
+        {
+          error (0, errno, "%s", quotef (infile));
+          return false;
+        }
 
       /* End of this file?  */
 
       if (n_read == 0)
-	return true;
+        return true;
 
       /* Write this block out.  */
 
       {
-	/* The following is ok, since we know that 0 < n_read.  */
-	size_t n = n_read;
-	if (full_write (STDOUT_FILENO, buf, n) != n)
-	  error (EXIT_FAILURE, errno, _("write error"));
+        /* The following is ok, since we know that 0 < n_read.  */
+        size_t n = n_read;
+        if (full_write (STDOUT_FILENO, buf, n) != n)
+          error (EXIT_FAILURE, errno, _("write error"));
       }
     }
 }
@@ -246,7 +239,7 @@ cat (
   /* Pointer to the next character in the input buffer.  */
   char *bpin;
 
-  /* Pointer to the first non-valid byte in the input buffer, i.e. the
+  /* Pointer to the first non-valid byte in the input buffer, i.e., the
      current end of the buffer.  */
   char *eob;
 
@@ -277,230 +270,231 @@ cat (
 
   bpout = outbuf;
 
-  for (;;)
+  while (true)
     {
       do
-	{
-	  /* Write if there are at least OUTSIZE bytes in OUTBUF.  */
-
-	  if (outbuf + outsize <= bpout)
-	    {
-	      char *wp = outbuf;
-	      size_t remaining_bytes;
-	      do
-		{
-		  if (full_write (STDOUT_FILENO, wp, outsize) != outsize)
-		    error (EXIT_FAILURE, errno, _("write error"));
-		  wp += outsize;
-		  remaining_bytes = bpout - wp;
-		}
-	      while (outsize <= remaining_bytes);
-
-	      /* Move the remaining bytes to the beginning of the
-		 buffer.  */
-
-	      memmove (outbuf, wp, remaining_bytes);
-	      bpout = outbuf + remaining_bytes;
-	    }
-
-	  /* Is INBUF empty?  */
-
-	  if (bpin > eob)
-	    {
-	      bool input_pending = false;
+        {
+          /* Write if there are at least OUTSIZE bytes in OUTBUF.  */
+
+          if (outbuf + outsize <= bpout)
+            {
+              char *wp = outbuf;
+              size_t remaining_bytes;
+              do
+                {
+                  if (full_write (STDOUT_FILENO, wp, outsize) != outsize)
+                    error (EXIT_FAILURE, errno, _("write error"));
+                  wp += outsize;
+                  remaining_bytes = bpout - wp;
+                }
+              while (outsize <= remaining_bytes);
+
+              /* Move the remaining bytes to the beginning of the
+                 buffer.  */
+
+              memmove (outbuf, wp, remaining_bytes);
+              bpout = outbuf + remaining_bytes;
+            }
+
+          /* Is INBUF empty?  */
+
+          if (bpin > eob)
+            {
+              bool input_pending = false;
 #ifdef FIONREAD
-	      int n_to_read = 0;
-
-	      /* Is there any input to read immediately?
-		 If not, we are about to wait,
-		 so write all buffered output before waiting.  */
-
-	      if (use_fionread
-		  && ioctl (input_desc, FIONREAD, &n_to_read) < 0)
-		{
-		  /* Ultrix returns EOPNOTSUPP on NFS;
-		     HP-UX returns ENOTTY on pipes.
-		     SunOS returns EINVAL and
-		     More/BSD returns ENODEV on special files
-		     like /dev/null.
-		     Irix-5 returns ENOSYS on pipes.  */
-		  if (errno == EOPNOTSUPP || errno == ENOTTY
-		      || errno == EINVAL || errno == ENODEV
-		      || errno == ENOSYS)
-		    use_fionread = false;
-		  else
-		    {
-		      error (0, errno, _("cannot do ioctl on %s"), quote (infile));
-		      newlines2 = newlines;
-		      return false;
-		    }
-		}
-	      if (n_to_read != 0)
-		input_pending = true;
+              int n_to_read = 0;
+
+              /* Is there any input to read immediately?
+                 If not, we are about to wait,
+                 so write all buffered output before waiting.  */
+
+              if (use_fionread
+                  && ioctl (input_desc, FIONREAD, &n_to_read) < 0)
+                {
+                  /* Ultrix returns EOPNOTSUPP on NFS;
+                     HP-UX returns ENOTTY on pipes.
+                     SunOS returns EINVAL and
+                     More/BSD returns ENODEV on special files
+                     like /dev/null.
+                     Irix-5 returns ENOSYS on pipes.  */
+                  if (errno == EOPNOTSUPP || errno == ENOTTY
+                      || errno == EINVAL || errno == ENODEV
+                      || errno == ENOSYS)
+                    use_fionread = false;
+                  else
+                    {
+                      error (0, errno, _("cannot do ioctl on %s"),
+                             quoteaf (infile));
+                      newlines2 = newlines;
+                      return false;
+                    }
+                }
+              if (n_to_read != 0)
+                input_pending = true;
 #endif
 
-	      if (input_pending)
-		write_pending (outbuf, &bpout);
-
-	      /* Read more input into INBUF.  */
-
-	      n_read = safe_read (input_desc, inbuf, insize);
-	      if (n_read == SAFE_READ_ERROR)
-		{
-		  error (0, errno, "%s", infile);
-		  write_pending (outbuf, &bpout);
-		  newlines2 = newlines;
-		  return false;
-		}
-	      if (n_read == 0)
-		{
-		  write_pending (outbuf, &bpout);
-		  newlines2 = newlines;
-		  return true;
-		}
-
-	      /* Update the pointers and insert a sentinel at the buffer
-		 end.  */
-
-	      bpin = inbuf;
-	      eob = bpin + n_read;
-	      *eob = '\n';
-	    }
-	  else
-	    {
-	      /* It was a real (not a sentinel) newline.  */
-
-	      /* Was the last line empty?
-		 (i.e. have two or more consecutive newlines been read?)  */
-
-	      if (++newlines > 0)
-		{
-		  if (newlines >= 2)
-		    {
-		      /* Limit this to 2 here.  Otherwise, with lots of
-			 consecutive newlines, the counter could wrap
-			 around at INT_MAX.  */
-		      newlines = 2;
-
-		      /* Are multiple adjacent empty lines to be substituted
-			 by single ditto (-s), and this was the second empty
-			 line?  */
-		      if (squeeze_blank)
-			{
-			  ch = *bpin++;
-			  continue;
-			}
-		    }
-
-		  /* Are line numbers to be written at empty lines (-n)?  */
-
-		  if (number & !number_nonblank)
-		    {
-		      next_line_num ();
-		      bpout = stpcpy (bpout, line_num_print);
-		    }
-		}
-
-	      /* Output a currency symbol if requested (-e).  */
-
-	      if (show_ends)
-		*bpout++ = '$';
-
-	      /* Output the newline.  */
-
-	      *bpout++ = '\n';
-	    }
-	  ch = *bpin++;
-	}
+              if (!input_pending)
+                write_pending (outbuf, &bpout);
+
+              /* Read more input into INBUF.  */
+
+              n_read = safe_read (input_desc, inbuf, insize);
+              if (n_read == SAFE_READ_ERROR)
+                {
+                  error (0, errno, "%s", quotef (infile));
+                  write_pending (outbuf, &bpout);
+                  newlines2 = newlines;
+                  return false;
+                }
+              if (n_read == 0)
+                {
+                  write_pending (outbuf, &bpout);
+                  newlines2 = newlines;
+                  return true;
+                }
+
+              /* Update the pointers and insert a sentinel at the buffer
+                 end.  */
+
+              bpin = inbuf;
+              eob = bpin + n_read;
+              *eob = '\n';
+            }
+          else
+            {
+              /* It was a real (not a sentinel) newline.  */
+
+              /* Was the last line empty?
+                 (i.e., have two or more consecutive newlines been read?)  */
+
+              if (++newlines > 0)
+                {
+                  if (newlines >= 2)
+                    {
+                      /* Limit this to 2 here.  Otherwise, with lots of
+                         consecutive newlines, the counter could wrap
+                         around at INT_MAX.  */
+                      newlines = 2;
+
+                      /* Are multiple adjacent empty lines to be substituted
+                         by single ditto (-s), and this was the second empty
+                         line?  */
+                      if (squeeze_blank)
+                        {
+                          ch = *bpin++;
+                          continue;
+                        }
+                    }
+
+                  /* Are line numbers to be written at empty lines (-n)?  */
+
+                  if (number && !number_nonblank)
+                    {
+                      next_line_num ();
+                      bpout = stpcpy (bpout, line_num_print);
+                    }
+                }
+
+              /* Output a currency symbol if requested (-e).  */
+
+              if (show_ends)
+                *bpout++ = '$';
+
+              /* Output the newline.  */
+
+              *bpout++ = '\n';
+            }
+          ch = *bpin++;
+        }
       while (ch == '\n');
 
       /* Are we at the beginning of a line, and line numbers are requested?  */
 
       if (newlines >= 0 && number)
-	{
-	  next_line_num ();
-	  bpout = stpcpy (bpout, line_num_print);
-	}
+        {
+          next_line_num ();
+          bpout = stpcpy (bpout, line_num_print);
+        }
 
       /* Here CH cannot contain a newline character.  */
 
       /* The loops below continue until a newline character is found,
-	 which means that the buffer is empty or that a proper newline
-	 has been found.  */
+         which means that the buffer is empty or that a proper newline
+         has been found.  */
 
-      /* If quoting, i.e. at least one of -v, -e, or -t specified,
-	 scan for chars that need conversion.  */
+      /* If quoting, i.e., at least one of -v, -e, or -t specified,
+         scan for chars that need conversion.  */
       if (show_nonprinting)
-	{
-	  for (;;)
-	    {
-	      if (ch >= 32)
-		{
-		  if (ch < 127)
-		    *bpout++ = ch;
-		  else if (ch == 127)
-		    {
-		      *bpout++ = '^';
-		      *bpout++ = '?';
-		    }
-		  else
-		    {
-		      *bpout++ = 'M';
-		      *bpout++ = '-';
-		      if (ch >= 128 + 32)
-			{
-			  if (ch < 128 + 127)
-			    *bpout++ = ch - 128;
-			  else
-			    {
-			      *bpout++ = '^';
-			      *bpout++ = '?';
-			    }
-			}
-		      else
-			{
-			  *bpout++ = '^';
-			  *bpout++ = ch - 128 + 64;
-			}
-		    }
-		}
-	      else if (ch == '\t' && !show_tabs)
-		*bpout++ = '\t';
-	      else if (ch == '\n')
-		{
-		  newlines = -1;
-		  break;
-		}
-	      else
-		{
-		  *bpout++ = '^';
-		  *bpout++ = ch + 64;
-		}
-
-	      ch = *bpin++;
-	    }
-	}
+        {
+          while (true)
+            {
+              if (ch >= 32)
+                {
+                  if (ch < 127)
+                    *bpout++ = ch;
+                  else if (ch == 127)
+                    {
+                      *bpout++ = '^';
+                      *bpout++ = '?';
+                    }
+                  else
+                    {
+                      *bpout++ = 'M';
+                      *bpout++ = '-';
+                      if (ch >= 128 + 32)
+                        {
+                          if (ch < 128 + 127)
+                            *bpout++ = ch - 128;
+                          else
+                            {
+                              *bpout++ = '^';
+                              *bpout++ = '?';
+                            }
+                        }
+                      else
+                        {
+                          *bpout++ = '^';
+                          *bpout++ = ch - 128 + 64;
+                        }
+                    }
+                }
+              else if (ch == '\t' && !show_tabs)
+                *bpout++ = '\t';
+              else if (ch == '\n')
+                {
+                  newlines = -1;
+                  break;
+                }
+              else
+                {
+                  *bpout++ = '^';
+                  *bpout++ = ch + 64;
+                }
+
+              ch = *bpin++;
+            }
+        }
       else
-	{
-	  /* Not quoting, neither of -v, -e, or -t specified.  */
-	  for (;;)
-	    {
-	      if (ch == '\t' && show_tabs)
-		{
-		  *bpout++ = '^';
-		  *bpout++ = ch + 64;
-		}
-	      else if (ch != '\n')
-		*bpout++ = ch;
-	      else
-		{
-		  newlines = -1;
-		  break;
-		}
-
-	      ch = *bpin++;
-	    }
-	}
+        {
+          /* Not quoting, neither of -v, -e, or -t specified.  */
+          while (true)
+            {
+              if (ch == '\t' && show_tabs)
+                {
+                  *bpout++ = '^';
+                  *bpout++ = ch + 64;
+                }
+              else if (ch != '\n')
+                *bpout++ = ch;
+              else
+                {
+                  newlines = -1;
+                  break;
+                }
+
+              ch = *bpin++;
+            }
+        }
     }
 }
 
@@ -533,8 +527,8 @@ main (int argc, char **argv)
   /* I-node number of the output.  */
   ino_t out_ino;
 
-  /* True if the output file should not be the same as any input file.  */
-  bool check_redirection = true;
+  /* True if the output is a regular file.  */
+  bool out_isreg;
 
   /* Nonzero if we have ever read standard input.  */
   bool have_read_stdin = false;
@@ -565,7 +559,7 @@ main (int argc, char **argv)
   };
 
   initialize_main (&argc, &argv);
-  program_name = argv[0];
+  set_program_name (argv[0]);
   setlocale (LC_ALL, "");
   bindtextdomain (PACKAGE, LOCALEDIR);
   textdomain (PACKAGE);
@@ -579,62 +573,62 @@ main (int argc, char **argv)
   /* Parse command line options.  */
 
   while ((c = getopt_long (argc, argv, "benstuvAET", long_options, NULL))
-	 != -1)
+         != -1)
     {
       switch (c)
-	{
-	case 'b':
-	  number = true;
-	  number_nonblank = true;
-	  break;
-
-	case 'e':
-	  show_ends = true;
-	  show_nonprinting = true;
-	  break;
-
-	case 'n':
-	  number = true;
-	  break;
-
-	case 's':
-	  squeeze_blank = true;
-	  break;
-
-	case 't':
-	  show_tabs = true;
-	  show_nonprinting = true;
-	  break;
-
-	case 'u':
-	  /* We provide the -u feature unconditionally.  */
-	  break;
-
-	case 'v':
-	  show_nonprinting = true;
-	  break;
-
-	case 'A':
-	  show_nonprinting = true;
-	  show_ends = true;
-	  show_tabs = true;
-	  break;
-
-	case 'E':
-	  show_ends = true;
-	  break;
-
-	case 'T':
-	  show_tabs = true;
-	  break;
-
-	case_GETOPT_HELP_CHAR;
-
-	case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
-
-	default:
-	  usage (EXIT_FAILURE);
-	}
+        {
+        case 'b':
+          number = true;
+          number_nonblank = true;
+          break;
+
+        case 'e':
+          show_ends = true;
+          show_nonprinting = true;
+          break;
+
+        case 'n':
+          number = true;
+          break;
+
+        case 's':
+          squeeze_blank = true;
+          break;
+
+        case 't':
+          show_tabs = true;
+          show_nonprinting = true;
+          break;
+
+        case 'u':
+          /* We provide the -u feature unconditionally.  */
+          break;
+
+        case 'v':
+          show_nonprinting = true;
+          break;
+
+        case 'A':
+          show_nonprinting = true;
+          show_ends = true;
+          show_tabs = true;
+          break;
+
+        case 'E':
+          show_ends = true;
+          break;
+
+        case 'T':
+          show_tabs = true;
+          break;
+
+        case_GETOPT_HELP_CHAR;
+
+        case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
+
+        default:
+          usage (EXIT_FAILURE);
+        }
     }
 
   /* Get device, i-node number, and optimal blocksize of output.  */
@@ -642,32 +636,16 @@ main (int argc, char **argv)
   if (fstat (STDOUT_FILENO, &stat_buf) < 0)
     error (EXIT_FAILURE, errno, _("standard output"));
 
-  outsize = ST_BLKSIZE (stat_buf);
-  /* Input file can be output file for non-regular files.
-     fstat on pipes returns S_IFSOCK on some systems, S_IFIFO
-     on others, so the checking should not be done for those types,
-     and to allow things like cat < /dev/tty > /dev/tty, checking
-     is not done for device files either.  */
-
-  if (S_ISREG (stat_buf.st_mode))
-    {
-      out_dev = stat_buf.st_dev;
-      out_ino = stat_buf.st_ino;
-    }
-  else
-    {
-      check_redirection = false;
-#ifdef lint  /* Suppress `used before initialized' warning.  */
-      out_dev = 0;
-      out_ino = 0;
-#endif
-    }
+  outsize = io_blksize (stat_buf);
+  out_dev = stat_buf.st_dev;
+  out_ino = stat_buf.st_ino;
+  out_isreg = S_ISREG (stat_buf.st_mode) != 0;
 
-  if (! (number | show_ends | squeeze_blank))
+  if (! (number || show_ends || squeeze_blank))
     {
       file_open_mode |= O_BINARY;
       if (O_BINARY && ! isatty (STDOUT_FILENO))
-	freopen (NULL, "wb", stdout);
+        xfreopen (NULL, "wb", stdout);
     }
 
   /* Check if any of the input files are the same as the output file.  */
@@ -680,109 +658,110 @@ main (int argc, char **argv)
   do
     {
       if (argind < argc)
-	infile = argv[argind];
+        infile = argv[argind];
 
       if (STREQ (infile, "-"))
-	{
-	  have_read_stdin = true;
-	  input_desc = STDIN_FILENO;
-	  if ((file_open_mode & O_BINARY) && ! isatty (STDIN_FILENO))
-	    freopen (NULL, "rb", stdin);
-	}
+        {
+          have_read_stdin = true;
+          input_desc = STDIN_FILENO;
+          if ((file_open_mode & O_BINARY) && ! isatty (STDIN_FILENO))
+            xfreopen (NULL, "rb", stdin);
+        }
       else
-	{
-	  input_desc = open (infile, file_open_mode);
-	  if (input_desc < 0)
-	    {
-	      error (0, errno, "%s", infile);
-	      ok = false;
-	      continue;
-	    }
-	}
+        {
+          input_desc = open (infile, file_open_mode);
+          if (input_desc < 0)
+            {
+              error (0, errno, "%s", quotef (infile));
+              ok = false;
+              continue;
+            }
+        }
 
       if (fstat (input_desc, &stat_buf) < 0)
-	{
-	  error (0, errno, "%s", infile);
-	  ok = false;
-	  goto contin;
-	}
-      insize = ST_BLKSIZE (stat_buf);
-
-      /* Compare the device and i-node numbers of this input file with
-	 the corresponding values of the (output file associated with)
-	 stdout, and skip this input file if they coincide.  Input
-	 files cannot be redirected to themselves.  */
-
-      if (check_redirection
-	  && stat_buf.st_dev == out_dev && stat_buf.st_ino == out_ino
-	  && (input_desc != STDIN_FILENO))
-	{
-	  error (0, 0, _("%s: input file is output file"), infile);
-	  ok = false;
-	  goto contin;
-	}
-
-      /* Select which version of `cat' to use.  If any format-oriented
-	 options were given use `cat'; otherwise use `simple_cat'.  */
-
-      if (! (number | show_ends | show_nonprinting
-	     | show_tabs | squeeze_blank))
-	{
-	  insize = max (insize, outsize);
-	  inbuf = xmalloc (insize + page_size - 1);
-
-	  ok &= simple_cat (ptr_align (inbuf, page_size), insize);
-	}
+        {
+          error (0, errno, "%s", quotef (infile));
+          ok = false;
+          goto contin;
+        }
+      insize = io_blksize (stat_buf);
+
+      fdadvise (input_desc, 0, 0, FADVISE_SEQUENTIAL);
+
+      /* Don't copy a nonempty regular file to itself, as that would
+         merely exhaust the output device.  It's better to catch this
+         error earlier rather than later.  */
+
+      if (out_isreg
+          && stat_buf.st_dev == out_dev && stat_buf.st_ino == out_ino
+          && lseek (input_desc, 0, SEEK_CUR) < stat_buf.st_size)
+        {
+          error (0, 0, _("%s: input file is output file"), quotef (infile));
+          ok = false;
+          goto contin;
+        }
+
+      /* Select which version of 'cat' to use.  If any format-oriented
+         options were given use 'cat'; otherwise use 'simple_cat'.  */
+
+      if (! (number || show_ends || show_nonprinting
+             || show_tabs || squeeze_blank))
+        {
+          insize = MAX (insize, outsize);
+          inbuf = xmalloc (insize + page_size - 1);
+
+          ok &= simple_cat (ptr_align (inbuf, page_size), insize);
+        }
       else
-	{
-	  inbuf = xmalloc (insize + 1 + page_size - 1);
-
-	  /* Why are
-	     (OUTSIZE - 1 + INSIZE * 4 + LINE_COUNTER_BUF_LEN + PAGE_SIZE - 1)
-	     bytes allocated for the output buffer?
-
-	     A test whether output needs to be written is done when the input
-	     buffer empties or when a newline appears in the input.  After
-	     output is written, at most (OUTSIZE - 1) bytes will remain in the
-	     buffer.  Now INSIZE bytes of input is read.  Each input character
-	     may grow by a factor of 4 (by the prepending of M-^).  If all
-	     characters do, and no newlines appear in this block of input, we
-	     will have at most (OUTSIZE - 1 + INSIZE * 4) bytes in the buffer.
-	     If the last character in the preceding block of input was a
-	     newline, a line number may be written (according to the given
-	     options) as the first thing in the output buffer. (Done after the
-	     new input is read, but before processing of the input begins.)
-	     A line number requires seldom more than LINE_COUNTER_BUF_LEN
-	     positions.
-
-	     Align the output buffer to a page size boundary, for efficency on
-	     some paging implementations, so add PAGE_SIZE - 1 bytes to the
-	     request to make room for the alignment.  */
-
-	  outbuf = xmalloc (outsize - 1 + insize * 4 + LINE_COUNTER_BUF_LEN
-			    + page_size - 1);
-
-	  ok &= cat (ptr_align (inbuf, page_size), insize,
-		     ptr_align (outbuf, page_size), outsize, show_nonprinting,
-		     show_tabs, number, number_nonblank, show_ends,
-		     squeeze_blank);
-
-	  free (outbuf);
-	}
+        {
+          inbuf = xmalloc (insize + 1 + page_size - 1);
+
+          /* Why are
+             (OUTSIZE - 1 + INSIZE * 4 + LINE_COUNTER_BUF_LEN + PAGE_SIZE - 1)
+             bytes allocated for the output buffer?
+
+             A test whether output needs to be written is done when the input
+             buffer empties or when a newline appears in the input.  After
+             output is written, at most (OUTSIZE - 1) bytes will remain in the
+             buffer.  Now INSIZE bytes of input is read.  Each input character
+             may grow by a factor of 4 (by the prepending of M-^).  If all
+             characters do, and no newlines appear in this block of input, we
+             will have at most (OUTSIZE - 1 + INSIZE * 4) bytes in the buffer.
+             If the last character in the preceding block of input was a
+             newline, a line number may be written (according to the given
+             options) as the first thing in the output buffer. (Done after the
+             new input is read, but before processing of the input begins.)
+             A line number requires seldom more than LINE_COUNTER_BUF_LEN
+             positions.
+
+             Align the output buffer to a page size boundary, for efficiency
+             on some paging implementations, so add PAGE_SIZE - 1 bytes to the
+             request to make room for the alignment.  */
+
+          outbuf = xmalloc (outsize - 1 + insize * 4 + LINE_COUNTER_BUF_LEN
+                            + page_size - 1);
+
+          ok &= cat (ptr_align (inbuf, page_size), insize,
+                     ptr_align (outbuf, page_size), outsize, show_nonprinting,
+                     show_tabs, number, number_nonblank, show_ends,
+                     squeeze_blank);
+
+          free (outbuf);
+        }
 
       free (inbuf);
 
     contin:
       if (!STREQ (infile, "-") && close (input_desc) < 0)
-	{
-	  error (0, errno, "%s", infile);
-	  ok = false;
-	}
+        {
+          error (0, errno, "%s", quotef (infile));
+          ok = false;
+        }
     }
   while (++argind < argc);
 
   if (have_read_stdin && close (STDIN_FILENO) < 0)
     error (EXIT_FAILURE, errno, _("closing standard input"));
 
-  exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
+  return ok ? EXIT_SUCCESS : EXIT_FAILURE;
 }