/*
   *  linux/fs/hpfs/name.c
   *
   *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
   *
   *  operations with filenames
   */
  
  #include "hpfs_fn.h"

  static inline int not_allowed_char(unsigned char c)
  {
  	return c<' ' || c=='"' || c=='*' || c=='/' || c==':' || c=='<' ||
  	      c=='>' || c=='?' || c=='\\' || c=='|';
  }
  
  static inline int no_dos_char(unsigned char c)
  {	/* Characters that are allowed in HPFS but not in DOS */
  	return c=='+' || c==',' || c==';' || c=='=' || c=='[' || c==']';
  }
  
  static inline unsigned char upcase(unsigned char *dir, unsigned char a)
  {
  	if (a<128 || a==255) return a>='a' && a<='z' ? a - 0x20 : a;
  	if (!dir) return a;
  	return dir[a-128];
  }
  
  unsigned char hpfs_upcase(unsigned char *dir, unsigned char a)
  {
  	return upcase(dir, a);
  }
  
  static inline unsigned char locase(unsigned char *dir, unsigned char a)
  {
  	if (a<128 || a==255) return a>='A' && a<='Z' ? a + 0x20 : a;
  	if (!dir) return a;
  	return dir[a];
  }

  int hpfs_chk_name(const unsigned char *name, unsigned *len)

  {
  	int i;
  	if (*len > 254) return -ENAMETOOLONG;
  	hpfs_adjust_length(name, len);
  	if (!*len) return -EINVAL;
  	for (i = 0; i < *len; i++) if (not_allowed_char(name[i])) return -EINVAL;
  	if (*len == 1) if (name[0] == '.') return -EINVAL;
  	if (*len == 2) if (name[0] == '.' && name[1] == '.') return -EINVAL;
  	return 0;
  }

  unsigned char *hpfs_translate_name(struct super_block *s, unsigned char *from,

  			  unsigned len, int lc, int lng)
  {

  	unsigned char *to;

  	int i;
  	if (hpfs_sb(s)->sb_chk >= 2) if (hpfs_is_name_long(from, len) != lng) {

  		pr_err("Long name flag mismatch - name ");

  		for (i = 0; i < len; i++)
  			pr_cont("%c", from[i]);
  		pr_cont(" misidentified as %s.
  ", lng ? "short" : "long");

  		pr_err("It's nothing serious. It could happen because of bug in OS/2.
  Set checks=normal to disable this message.
  ");

  	}
  	if (!lc) return from;
  	if (!(to = kmalloc(len, GFP_KERNEL))) {

  		pr_err("can't allocate memory for name conversion buffer
  ");

  		return from;
  	}
  	for (i = 0; i < len; i++) to[i] = locase(hpfs_sb(s)->sb_cp_table,from[i]);
  	return to;
  }

  int hpfs_compare_names(struct super_block *s,
  		       const unsigned char *n1, unsigned l1,
  		       const unsigned char *n2, unsigned l2, int last)

  {
  	unsigned l = l1 < l2 ? l1 : l2;
  	unsigned i;
  	if (last) return -1;
  	for (i = 0; i < l; i++) {
  		unsigned char c1 = upcase(hpfs_sb(s)->sb_cp_table,n1[i]);
  		unsigned char c2 = upcase(hpfs_sb(s)->sb_cp_table,n2[i]);
  		if (c1 < c2) return -1;
  		if (c1 > c2) return 1;
  	}
  	if (l1 < l2) return -1;
  	if (l1 > l2) return 1;
  	return 0;
  }

  int hpfs_is_name_long(const unsigned char *name, unsigned len)

  {
  	int i,j;
  	for (i = 0; i < len && name[i] != '.'; i++)
  		if (no_dos_char(name[i])) return 1;
  	if (!i || i > 8) return 1;
  	if (i == len) return 0;
  	for (j = i + 1; j < len; j++)
  		if (name[j] == '.' || no_dos_char(name[i])) return 1;
  	return j - i > 4;
  }
  
  /* OS/2 clears dots and spaces at the end of file name, so we have to */

  void hpfs_adjust_length(const unsigned char *name, unsigned *len)

  {
  	if (!*len) return;
  	if (*len == 1 && name[0] == '.') return;
  	if (*len == 2 && name[0] == '.' && name[1] == '.') return;
  	while (*len && (name[*len - 1] == '.' || name[*len - 1] == ' '))
  		(*len)--;
  }