/* SPDX-License-Identifier: GPL-2.0-or-later */

  /*
   * cifs_unicode:  Unicode kernel case support
   *
   * Function:
   *     Convert a unicode character to upper or lower case using
   *     compressed tables.
   *

   *   Copyright (c) International Business Machines  Corp., 2000,2009

   *

   * Notes:
   *     These APIs are based on the C library functions.  The semantics
   *     should match the C functions but with expanded size operands.
   *
   *     The upper/lower functions are based on a table created by mkupr.
   *     This is a compressed table of upper and lower case conversion.

   */

  #ifndef _CIFS_UNICODE_H
  #define _CIFS_UNICODE_H

  
  #include <asm/byteorder.h>
  #include <linux/types.h>
  #include <linux/nls.h>
  
  #define  UNIUPR_NOLOWER		/* Example to not expand lower case tables */

  /*
   * Windows maps these to the user defined 16 bit Unicode range since they are
   * reserved symbols (along with \ and /), otherwise illegal to store
   * in filenames in NTFS
   */

  #define UNI_ASTERISK    (__u16) ('*' + 0xF000)

  #define UNI_QUESTION    (__u16) ('?' + 0xF000)
  #define UNI_COLON       (__u16) (':' + 0xF000)
  #define UNI_GRTRTHAN    (__u16) ('>' + 0xF000)
  #define UNI_LESSTHAN    (__u16) ('<' + 0xF000)
  #define UNI_PIPE        (__u16) ('|' + 0xF000)
  #define UNI_SLASH       (__u16) ('\\' + 0xF000)

  /*
   * Macs use an older "SFM" mapping of the symbols above. Fortunately it does
   * not conflict (although almost does) with the mapping above.
   */

  #define SFM_DOUBLEQUOTE ((__u16) 0xF020)

  #define SFM_ASTERISK    ((__u16) 0xF021)
  #define SFM_QUESTION    ((__u16) 0xF025)
  #define SFM_COLON       ((__u16) 0xF022)
  #define SFM_GRTRTHAN    ((__u16) 0xF024)
  #define SFM_LESSTHAN    ((__u16) 0xF023)
  #define SFM_PIPE        ((__u16) 0xF027)
  #define SFM_SLASH       ((__u16) 0xF026)

  #define SFM_SPACE	((__u16) 0xF028)
  #define SFM_PERIOD	((__u16) 0xF029)

  
  /*
   * Mapping mechanism to use when one of the seven reserved characters is
   * encountered.  We can only map using one of the mechanisms at a time
   * since otherwise readdir could return directory entries which we would
   * not be able to open
   *
   * NO_MAP_UNI_RSVD  = do not perform any remapping of the character
   * SFM_MAP_UNI_RSVD = map reserved characters using SFM scheme (MAC compatible)
   * SFU_MAP_UNI_RSVD = map reserved characters ala SFU ("mapchars" option)
   *
   */
  #define NO_MAP_UNI_RSVD		0
  #define SFM_MAP_UNI_RSVD	1
  #define SFU_MAP_UNI_RSVD	2

  /* Just define what we want from uniupr.h.  We don't want to define the tables
   * in each source file.
   */
  #ifndef	UNICASERANGE_DEFINED
  struct UniCaseRange {
  	wchar_t start;
  	wchar_t end;
  	signed char *table;
  };
  #endif				/* UNICASERANGE_DEFINED */
  
  #ifndef UNIUPR_NOUPPER
  extern signed char CifsUniUpperTable[512];
  extern const struct UniCaseRange CifsUniUpperRange[];
  #endif				/* UNIUPR_NOUPPER */
  
  #ifndef UNIUPR_NOLOWER

  extern signed char CifsUniLowerTable[512];
  extern const struct UniCaseRange CifsUniLowerRange[];

  #endif				/* UNIUPR_NOLOWER */
  
  #ifdef __KERNEL__

  int cifs_from_utf16(char *to, const __le16 *from, int tolen, int fromlen,

  		    const struct nls_table *cp, int map_type);

  int cifs_utf16_bytes(const __le16 *from, int maxbytes,
  		     const struct nls_table *codepage);
  int cifs_strtoUTF16(__le16 *, const char *, int, const struct nls_table *);
  char *cifs_strndup_from_utf16(const char *src, const int maxlen,
  			      const bool is_unicode,
  			      const struct nls_table *codepage);
  extern int cifsConvertToUTF16(__le16 *target, const char *source, int maxlen,
  			      const struct nls_table *cp, int mapChars);

  extern int cifs_remap(struct cifs_sb_info *cifs_sb);

  extern __le16 *cifs_strndup_to_utf16(const char *src, const int maxlen,
  				     int *utf16_len, const struct nls_table *cp,
  				     int remap);

  #endif

  wchar_t cifs_toupper(wchar_t in);

  /*
   * UniStrcat:  Concatenate the second string to the first
   *
   * Returns:
   *     Address of the first string
   */

  static inline __le16 *
  UniStrcat(__le16 *ucs1, const __le16 *ucs2)

  {

  	__le16 *anchor = ucs1;	/* save a pointer to start of ucs1 */

  
  	while (*ucs1++) ;	/* To end of first string */
  	ucs1--;			/* Return to the null */
  	while ((*ucs1++ = *ucs2++)) ;	/* copy string 2 over */
  	return anchor;
  }
  
  /*
   * UniStrchr:  Find a character in a string
   *
   * Returns:
   *     Address of first occurrence of character in string
   *     or NULL if the character is not in the string
   */
  static inline wchar_t *

  UniStrchr(const wchar_t *ucs, wchar_t uc)

  {
  	while ((*ucs != uc) && *ucs)
  		ucs++;
  
  	if (*ucs == uc)
  		return (wchar_t *) ucs;
  	return NULL;
  }
  
  /*
   * UniStrcmp:  Compare two strings
   *
   * Returns:
   *     < 0:  First string is less than second
   *     = 0:  Strings are equal
   *     > 0:  First string is greater than second
   */
  static inline int

  UniStrcmp(const wchar_t *ucs1, const wchar_t *ucs2)

  {
  	while ((*ucs1 == *ucs2) && *ucs1) {
  		ucs1++;
  		ucs2++;
  	}
  	return (int) *ucs1 - (int) *ucs2;
  }
  
  /*
   * UniStrcpy:  Copy a string
   */
  static inline wchar_t *

  UniStrcpy(wchar_t *ucs1, const wchar_t *ucs2)

  {
  	wchar_t *anchor = ucs1;	/* save the start of result string */
  
  	while ((*ucs1++ = *ucs2++)) ;
  	return anchor;
  }
  
  /*
   * UniStrlen:  Return the length of a string (in 16 bit Unicode chars not bytes)
   */
  static inline size_t

  UniStrlen(const wchar_t *ucs1)

  {
  	int i = 0;
  
  	while (*ucs1++)
  		i++;
  	return i;
  }
  
  /*

   * UniStrnlen:  Return the length (in 16 bit Unicode chars not bytes) of a
   *		string (length limited)

   */
  static inline size_t

  UniStrnlen(const wchar_t *ucs1, int maxlen)

  {
  	int i = 0;
  
  	while (*ucs1++) {
  		i++;
  		if (i >= maxlen)
  			break;
  	}
  	return i;
  }
  
  /*
   * UniStrncat:  Concatenate length limited string
   */
  static inline wchar_t *

  UniStrncat(wchar_t *ucs1, const wchar_t *ucs2, size_t n)

  {
  	wchar_t *anchor = ucs1;	/* save pointer to string 1 */
  
  	while (*ucs1++) ;
  	ucs1--;			/* point to null terminator of s1 */
  	while (n-- && (*ucs1 = *ucs2)) {	/* copy s2 after s1 */
  		ucs1++;
  		ucs2++;
  	}
  	*ucs1 = 0;		/* Null terminate the result */
  	return (anchor);
  }
  
  /*
   * UniStrncmp:  Compare length limited string
   */
  static inline int

  UniStrncmp(const wchar_t *ucs1, const wchar_t *ucs2, size_t n)

  {
  	if (!n)
  		return 0;	/* Null strings are equal */
  	while ((*ucs1 == *ucs2) && *ucs1 && --n) {
  		ucs1++;
  		ucs2++;
  	}
  	return (int) *ucs1 - (int) *ucs2;
  }
  
  /*
   * UniStrncmp_le:  Compare length limited string - native to little-endian
   */
  static inline int

  UniStrncmp_le(const wchar_t *ucs1, const wchar_t *ucs2, size_t n)

  {
  	if (!n)
  		return 0;	/* Null strings are equal */
  	while ((*ucs1 == __le16_to_cpu(*ucs2)) && *ucs1 && --n) {
  		ucs1++;
  		ucs2++;
  	}
  	return (int) *ucs1 - (int) __le16_to_cpu(*ucs2);
  }
  
  /*
   * UniStrncpy:  Copy length limited string with pad
   */
  static inline wchar_t *

  UniStrncpy(wchar_t *ucs1, const wchar_t *ucs2, size_t n)

  {
  	wchar_t *anchor = ucs1;
  
  	while (n-- && *ucs2)	/* Copy the strings */
  		*ucs1++ = *ucs2++;
  
  	n++;
  	while (n--)		/* Pad with nulls */
  		*ucs1++ = 0;
  	return anchor;
  }
  
  /*
   * UniStrncpy_le:  Copy length limited string with pad to little-endian
   */
  static inline wchar_t *

  UniStrncpy_le(wchar_t *ucs1, const wchar_t *ucs2, size_t n)

  {
  	wchar_t *anchor = ucs1;
  
  	while (n-- && *ucs2)	/* Copy the strings */
  		*ucs1++ = __le16_to_cpu(*ucs2++);
  
  	n++;
  	while (n--)		/* Pad with nulls */
  		*ucs1++ = 0;
  	return anchor;
  }
  
  /*
   * UniStrstr:  Find a string in a string
   *
   * Returns:
   *     Address of first match found
   *     NULL if no matching string is found
   */
  static inline wchar_t *

  UniStrstr(const wchar_t *ucs1, const wchar_t *ucs2)

  {
  	const wchar_t *anchor1 = ucs1;
  	const wchar_t *anchor2 = ucs2;
  
  	while (*ucs1) {

  		if (*ucs1 == *ucs2) {
  			/* Partial match found */

  			ucs1++;
  			ucs2++;
  		} else {
  			if (!*ucs2)	/* Match found */
  				return (wchar_t *) anchor1;
  			ucs1 = ++anchor1;	/* No match */
  			ucs2 = anchor2;
  		}
  	}
  
  	if (!*ucs2)		/* Both end together */
  		return (wchar_t *) anchor1;	/* Match found */
  	return NULL;		/* No match */
  }
  
  #ifndef UNIUPR_NOUPPER
  /*
   * UniToupper:  Convert a unicode character to upper case
   */
  static inline wchar_t
  UniToupper(register wchar_t uc)
  {
  	register const struct UniCaseRange *rp;

  	if (uc < sizeof(CifsUniUpperTable)) {
  		/* Latin characters */

  		return uc + CifsUniUpperTable[uc];	/* Use base tables */
  	} else {
  		rp = CifsUniUpperRange;	/* Use range tables */
  		while (rp->start) {
  			if (uc < rp->start)	/* Before start of range */
  				return uc;	/* Uppercase = input */
  			if (uc <= rp->end)	/* In range */
  				return uc + rp->table[uc - rp->start];
  			rp++;	/* Try next range */
  		}
  	}
  	return uc;		/* Past last range */
  }
  
  /*
   * UniStrupr:  Upper case a unicode string
   */

  static inline __le16 *
  UniStrupr(register __le16 *upin)

  {

  	register __le16 *up;

  
  	up = upin;
  	while (*up) {		/* For all characters */

  		*up = cpu_to_le16(UniToupper(le16_to_cpu(*up)));

  		up++;
  	}
  	return upin;		/* Return input pointer */
  }
  #endif				/* UNIUPR_NOUPPER */
  
  #ifndef UNIUPR_NOLOWER
  /*
   * UniTolower:  Convert a unicode character to lower case
   */
  static inline wchar_t

  UniTolower(register wchar_t uc)

  {

  	register const struct UniCaseRange *rp;

  	if (uc < sizeof(CifsUniLowerTable)) {

  		/* Latin characters */

  		return uc + CifsUniLowerTable[uc];	/* Use base tables */

  	} else {

  		rp = CifsUniLowerRange;	/* Use range tables */

  		while (rp->start) {
  			if (uc < rp->start)	/* Before start of range */
  				return uc;	/* Uppercase = input */
  			if (uc <= rp->end)	/* In range */
  				return uc + rp->table[uc - rp->start];
  			rp++;	/* Try next range */
  		}
  	}
  	return uc;		/* Past last range */
  }
  
  /*
   * UniStrlwr:  Lower case a unicode string
   */
  static inline wchar_t *

  UniStrlwr(register wchar_t *upin)

  {
  	register wchar_t *up;
  
  	up = upin;
  	while (*up) {		/* For all characters */
  		*up = UniTolower(*up);
  		up++;
  	}
  	return upin;		/* Return input pointer */
  }
  
  #endif

  
  #endif /* _CIFS_UNICODE_H */