Update from FSF via patch-2.2.93.

1 files changed, 115 insertions, 91 deletions

diff --git a/lib/backupfile.c b/lib/backupfile.c
index 95f19fecf..4b0f2ec58 100644
--- a/lib/backupfile.c
+++ b/lib/backupfile.c
@@ -1,5 +1,5 @@
 /* backupfile.c -- make Emacs style backup file names
-   Copyright (C) 1990 Free Software Foundation, Inc.
+   Copyright (C) 1990,1991,1992,1993,1995,1997 Free Software Foundation, 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
@@ -12,20 +12,22 @@
    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.  */
+   along with this program; see the file COPYING.
+   If not, write to the Free Software Foundation,
+   59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
 
-/* David MacKenzie <djm@gnu.ai.mit.edu>.
-   Some algorithms adapted from GNU Emacs.  */
+/* Written by David MacKenzie <djm@gnu.ai.mit.edu>.
+   Some algorithms adapted from GNU Emacs. */
 
 #if HAVE_CONFIG_H
 # include <config.h>
 #endif
 
+#include <argmatch.h>
+#include <backupfile.h>
+
 #include <stdio.h>
-#include <ctype.h>
 #include <sys/types.h>
-#include "backupfile.h"
 #if HAVE_STRING_H
 # include <string.h>
 #else
@@ -34,10 +36,10 @@
 
 #if HAVE_DIRENT_H
 # include <dirent.h>
-# define NLENGTH(Direct) (strlen((Direct)->d_name))
+# define NLENGTH(direct) strlen ((direct)->d_name)
 #else
 # define dirent direct
-# define NLENGTH(Direct) ((Direct)->d_namlen)
+# define NLENGTH(direct) ((size_t) (direct)->d_namlen)
 # if HAVE_SYS_NDIR_H
 #  include <sys/ndir.h>
 # endif
@@ -50,7 +52,7 @@
 #endif
 
 #if CLOSEDIR_VOID
-/* Fake a return value.  */
+/* Fake a return value. */
 # define CLOSEDIR(d) (closedir (d), 0)
 #else
 # define CLOSEDIR(d) closedir (d)
@@ -62,78 +64,103 @@
 char *malloc ();
 #endif
 
-#if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
-# define IN_CTYPE_DOMAIN(Char) 1
+#if HAVE_DIRENT_H || HAVE_NDIR_H || HAVE_SYS_DIR_H || HAVE_SYS_NDIR_H
+# define HAVE_DIR 1
 #else
-# define IN_CTYPE_DOMAIN(Char) isascii(Char)
+# define HAVE_DIR 0
 #endif
 
-#define ISDIGIT(Char) (IN_CTYPE_DOMAIN ((unsigned char) (Char)) \
-		       && isdigit ((unsigned char) (Char)))
-
-#if HAVE_UNISTD_H
-# include <unistd.h>
+#if HAVE_LIMITS_H
+# include <limits.h>
 #endif
-
-#ifdef _POSIX_VERSION
-/* POSIX does not require that the d_ino field be present, and some
-   systems do not provide it.  */
-# define REAL_DIR_ENTRY(Dp) 1
+#ifndef CHAR_BIT
+#define CHAR_BIT 8
+#endif
+/* Upper bound on the string length of an integer converted to string.
+   302 / 1000 is ceil (log10 (2.0)).  Subtract 1 for the sign bit;
+   add 1 for integer division truncation; add 1 more for a minus sign.  */
+#define INT_STRLEN_BOUND(t) ((sizeof (t) * CHAR_BIT - 1) * 302 / 1000 + 2)
+
+/* ISDIGIT differs from isdigit, as follows:
+   - Its arg may be any int or unsigned int; it need not be an unsigned char.
+   - It's guaranteed to evaluate its argument exactly once.
+   - It's typically faster.
+   Posix 1003.2-1992 section 2.5.2.1 page 50 lines 1556-1558 says that
+   only '0' through '9' are digits.  Prefer ISDIGIT to isdigit unless
+   it's important to use the locale's definition of `digit' even when the
+   host does not conform to Posix.  */
+#define ISDIGIT(c) ((unsigned) (c) - '0' <= 9)
+
+#if D_INO_IN_DIRENT
+# define REAL_DIR_ENTRY(dp) ((dp)->d_ino != 0)
 #else
-# define REAL_DIR_ENTRY(Dp) ((Dp)->d_ino != 0)
+# define REAL_DIR_ENTRY(dp) 1
 #endif
 
-/* Which type of backup file names are generated.  */
+/* Which type of backup file names are generated. */
 enum backup_type backup_type = none;
 
 /* The extension added to file names to produce a simple (as opposed
-   to numbered) backup file name.  */
-char *simple_backup_suffix = "~";
+   to numbered) backup file name. */
+const char *simple_backup_suffix = ".orig";
 
-char *basename ();
-char *dirname ();
-static char *concat ();
-char *find_backup_file_name ();
-static char *make_version_name ();
-static int max_backup_version ();
-static int version_number ();
+static int max_backup_version __BACKUPFILE_P ((const char *, const char *));
+static int version_number __BACKUPFILE_P ((const char *, const char *, size_t));
 
 /* Return the name of the new backup file for file FILE,
    allocated with malloc.  Return 0 if out of memory.
    FILE must not end with a '/' unless it is the root directory.
-   Do not call this function if backup_type == none.  */
+   Do not call this function if backup_type == none. */
 
 char *
 find_backup_file_name (file)
      const char *file;
 {
-  char *dir;
-  char *base_versions;
-  int highest_backup;
-
-  if (backup_type == simple)
-    return concat (file, simple_backup_suffix);
-  base_versions = concat (basename (file), ".~");
-  if (base_versions == 0)
-    return 0;
-  dir = dirname (file);
-  if (dir == 0)
+  size_t backup_suffix_size_max;
+  size_t file_len = strlen (file);
+  size_t numbered_suffix_size_max = INT_STRLEN_BOUND (int) + 4;
+  char *s;
+  const char *suffix = simple_backup_suffix;
+
+  /* Allow room for simple or `.~N~' backups.  */
+  backup_suffix_size_max = strlen (simple_backup_suffix) + 1;
+  if (HAVE_DIR && backup_suffix_size_max < numbered_suffix_size_max)
+    backup_suffix_size_max = numbered_suffix_size_max;
+
+  s = malloc (file_len + backup_suffix_size_max + numbered_suffix_size_max);
+  if (s)
     {
-      free (base_versions);
-      return 0;
+      strcpy (s, file);
+
+#if HAVE_DIR
+      if (backup_type != simple)
+	{
+	  int highest_backup;
+	  size_t dir_len = base_name (s) - s;
+
+	  strcpy (s + dir_len, ".");
+	  highest_backup = max_backup_version (file + dir_len, s);
+	  if (! (backup_type == numbered_existing && highest_backup == 0))
+	    {
+	      char *numbered_suffix = s + (file_len + backup_suffix_size_max);
+	      sprintf (numbered_suffix, ".~%d~", highest_backup + 1);
+	      suffix = numbered_suffix;
+	    }
+	  strcpy (s, file);
+	}
+#endif /* HAVE_DIR */
+
+      addext (s, suffix, '~');
     }
-  highest_backup = max_backup_version (base_versions, dir);
-  free (base_versions);
-  free (dir);
-  if (backup_type == numbered_existing && highest_backup == 0)
-    return concat (file, simple_backup_suffix);
-  return make_version_name (file, highest_backup + 1);
+  return s;
 }
 
+#if HAVE_DIR
+
 /* Return the number of the highest-numbered backup file for file
    FILE in directory DIR.  If there are no numbered backups
    of FILE in DIR, or an error occurs reading DIR, return 0.
-   FILE should already have ".~" appended to it.  */
+   */
 
 static int
 max_backup_version (file, dir)
@@ -155,7 +182,7 @@ max_backup_version (file, dir)
 
   while ((dp = readdir (dirp)) != 0)
     {
-      if (!REAL_DIR_ENTRY (dp) || NLENGTH (dp) <= file_name_length)
+      if (!REAL_DIR_ENTRY (dp) || NLENGTH (dp) < file_name_length + 4)
 	continue;
 
       this_version = version_number (file, dp->d_name, file_name_length);
@@ -167,62 +194,59 @@ max_backup_version (file, dir)
   return highest_version;
 }
 
-/* Return a string, allocated with malloc, containing
-   "FILE.~VERSION~".  Return 0 if out of memory.  */
-
-static char *
-make_version_name (file, version)
-     const char *file;
-     int version;
-{
-  char *backup_name;
-
-  backup_name = malloc (strlen (file) + 16);
-  if (backup_name == 0)
-    return 0;
-  sprintf (backup_name, "%s.~%d~", file, version);
-  return backup_name;
-}
-
 /* If BACKUP is a numbered backup of BASE, return its version number;
    otherwise return 0.  BASE_LENGTH is the length of BASE.
-   BASE should already have ".~" appended to it.  */
+   */
 
 static int
 version_number (base, backup, base_length)
      const char *base;
      const char *backup;
-     int base_length;
+     size_t base_length;
 {
   int version;
   const char *p;
 
   version = 0;
-  if (!strncmp (base, backup, base_length) && ISDIGIT (backup[base_length]))
+  if (strncmp (base, backup, base_length) == 0
+      && backup[base_length] == '.'
+      && backup[base_length + 1] == '~')
     {
-      for (p = &backup[base_length]; ISDIGIT (*p); ++p)
+      for (p = &backup[base_length + 2]; ISDIGIT (*p); ++p)
 	version = version * 10 + *p - '0';
       if (p[0] != '~' || p[1])
 	version = 0;
     }
   return version;
 }
+#endif /* HAVE_DIR */
 
-/* Return the newly-allocated concatenation of STR1 and STR2.
-   If out of memory, return 0.  */
+static const char * const backup_args[] =
+{
+  "never", "simple", "nil", "existing", "t", "numbered", 0
+};
 
-static char *
-concat (str1, str2)
-     const char *str1;
-     const char *str2;
+static const enum backup_type backup_types[] =
 {
-  char *newstr;
-  int str1_length = strlen (str1);
+  simple, simple, numbered_existing, numbered_existing, numbered, numbered
+};
 
-  newstr = malloc (str1_length + strlen (str2) + 1);
-  if (newstr == 0)
-    return 0;
-  strcpy (newstr, str1);
-  strcpy (newstr + str1_length, str2);
-  return newstr;
+/* Return the type of backup indicated by VERSION.
+   Unique abbreviations are accepted. */
+
+enum backup_type
+get_version (version)
+     const char *version;
+{
+  int i;
+
+  if (version == 0 || *version == 0)
+    return numbered_existing;
+  i = argmatch (version, backup_args);
+  if (i < 0)
+    {
+      invalid_arg ("version control type", version, i);
+      exit (2);
+    }
+  return backup_types[i];
 }