Update.

	* misc/mntent_r.c: Allow spaces and tabs in entry names by
	encoding these characters.

1 files changed, 111 insertions, 12 deletions

diff --git a/misc/mntent_r.c b/misc/mntent_r.c
index f6ee1ca64e..43cb3f732a 100644
--- a/misc/mntent_r.c
+++ b/misc/mntent_r.c
@@ -1,5 +1,5 @@
 /* Utilities for reading/writing fstab, mtab, etc.
-   Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
+   Copyright (C) 1995, 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -48,12 +48,50 @@ __endmntent (FILE *stream)
 weak_alias (__endmntent, endmntent)
 
 
+/* Since the values in a line are separated by spaces, a name cannot
+   contain a space.  Therefore some programs encode spaces in names
+   by the strings "\040".  We undo the encoding when reading an entry.
+   The decoding happens in place.  */
+static char *
+decode_name (char *buf)
+{
+  char *rp = buf;
+  char *wp = buf;
+
+  do
+    if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '4' && rp[3] == '0')
+      {
+	/* \040 is a SPACE.  */
+	*wp++ = ' ';
+	rp += 3;
+      }
+    else if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '1' && rp[3] == '2')
+      {
+	/* \012 is a TAB.  */
+	*wp++ = '\t';
+	rp += 3;
+      }
+    else if (rp[0] == '\\' && rp[1] == '\\')
+      {
+	/* We have to escape \\ to be able to represent all characters.  */
+	*wp++ = '\\';
+	rp += 1;
+      }
+    else
+      *wp++ = *rp;
+  while (*rp++ != '\0');
+
+  return buf;
+}
+
+
 /* Read one mount table entry from STREAM.  Returns a pointer to storage
    reused on the next call, or null for EOF or error (use feof/ferror to
    check).  */
 struct mntent *
 __getmntent_r (FILE *stream, struct mntent *mp, char *buffer, int bufsiz)
 {
+  char *cp;
   char *head;
 
   flockfile (stream);
@@ -81,18 +119,23 @@ __getmntent_r (FILE *stream, struct mntent *mp, char *buffer, int bufsiz)
 
       head = buffer + strspn (buffer, " \t");
       /* skip empty lines and comment lines:  */
-    } while (head[0] == '\0' || head[0] == '#');
+    }
+  while (head[0] == '\0' || head[0] == '#');
 
-  mp->mnt_fsname = __strsep (&head, " \t") ?: (char *) "";
+  cp = __strsep (&head, " \t");
+  mp->mnt_fsname = cp != NULL ? decode_name (cp) : (char *) "";
   if (head)
     head += strspn (head, " \t");
-  mp->mnt_dir = __strsep (&head, " \t") ?: (char *) "";
+  cp = __strsep (&head, " \t");
+  mp->mnt_dir = cp != NULL ? decode_name (cp) : (char *) "";
   if (head)
     head += strspn (head, " \t");
-  mp->mnt_type = __strsep (&head, " \t") ?: (char *) "";
+  cp = __strsep (&head, " \t");
+  mp->mnt_type = cp != NULL ? decode_name (cp) : (char *) "";
   if (head)
     head += strspn (head, " \t");
-  mp->mnt_opts = __strsep (&head, " \t") ?: (char *) "";
+  cp = __strsep (&head, " \t");
+  mp->mnt_opts = cp != NULL ? decode_name (cp) : (char *) "";
   switch (head ? sscanf (head, " %d %d ", &mp->mnt_freq, &mp->mnt_passno) : 0)
     {
     case 0:
@@ -107,21 +150,77 @@ __getmntent_r (FILE *stream, struct mntent *mp, char *buffer, int bufsiz)
 }
 weak_alias (__getmntent_r, getmntent_r)
 
+
+/* We have to use an encoding for names if they contain spaces or tabs.
+   To be able to represent all characters we also have to escape the
+   backslash itself.  This "function" must be a macro since we use
+   `alloca'.  */
+#define encode_name(name) \
+  do {									      \
+    const char *rp = name;						      \
+									      \
+    while (*rp != '\0')							      \
+      if (*rp == ' ' || *rp == '\t' || *rp == '\\')			      \
+	break;								      \
+									      \
+    if (*rp != '\0')							      \
+      {									      \
+	/* In the worst case the length of the string can increase to	      \
+	   founr times the current length.  */				      \
+	char *wp = (char *) alloca (strlen (name) * 4 + 1);		      \
+									      \
+	rp = name;							      \
+	do								      \
+	  if (*rp == ' ')						      \
+	    {								      \
+	      *wp++ = '\\';						      \
+	      *wp++ = '0';						      \
+	      *wp++ = '4';						      \
+	      *wp++ = '0';						      \
+	    }								      \
+	  else if (*rp == '\t')						      \
+	    {								      \
+	      *wp++ = '\\';						      \
+	      *wp++ = '0';						      \
+	      *wp++ = '1';						      \
+	      *wp++ = '2';						      \
+	    }								      \
+	  else if (*rp == '\\')						      \
+	    {								      \
+	      *wp++ = '\\';						      \
+	      *wp++ = '\\';						      \
+	    }								      \
+	  else								      \
+	    *wp++ = *rp;						      \
+	while (*rp++ != '\0');						      \
+									      \
+	name = wp;							      \
+      }									      \
+  } while (0)
+
+
 /* Write the mount table entry described by MNT to STREAM.
    Return zero on success, nonzero on failure.  */
 int
 __addmntent (FILE *stream, const struct mntent *mnt)
 {
+  struct mntent mntcopy = *mnt;
   if (fseek (stream, 0, SEEK_END))
     return 1;
 
+  /* Encode spaces and tabs in the names.  */
+  encode_name (mntcopy.mnt_fsname);
+  encode_name (mntcopy.mnt_dir);
+  encode_name (mntcopy.mnt_type);
+  encode_name (mntcopy.mnt_opts);
+
   return (fprintf (stream, "%s %s %s %s %d %d\n",
-		   mnt->mnt_fsname,
-		   mnt->mnt_dir,
-		   mnt->mnt_type,
-		   mnt->mnt_opts,
-		   mnt->mnt_freq,
-		   mnt->mnt_passno)
+		   mntcopy.mnt_fsname,
+		   mntcopy.mnt_dir,
+		   mntcopy.mnt_type,
+		   mntcopy.mnt_opts,
+		   mntcopy.mnt_freq,
+		   mntcopy.mnt_passno)
 	  < 0 ? 1 : 0);
 }
 weak_alias (__addmntent, addmntent)