// © 2016 and later: Unicode, Inc. and others.

// License & terms of use: http://www.unicode.org/copyright.html

/*

*******************************************************************************

*

*   Copyright (C) 1998-2014, International Business Machines

*   Corporation and others.  All Rights Reserved.

*

*******************************************************************************

*   file name:  ustr_cnv.cpp

*   encoding:   UTF-8

*   tab size:   8 (not used)

*   indentation:4

*

*   created on: 2004aug24

*   created by: Markus W. Scherer

*

*   Character conversion functions moved here from ustring.c

*/

#include "unicode/utypes.h"

#if !UCONFIG_NO_CONVERSION

#include "unicode/ustring.h"

#include "unicode/ucnv.h"

#include "cstring.h"

#include "cmemory.h"

#include "umutex.h"

#include "ustr_cnv.h"

/* mutexed access to a shared default converter ----------------------------- */

static UConverter *gDefaultConverter = NULL;

U_CAPI UConverter* U_EXPORT2

u_getDefaultConverter(UErrorCode *status)

{

    UConverter *converter = NULL;

    if (gDefaultConverter != NULL) {

        umtx_lock(NULL);

        /* need to check to make sure it wasn't taken out from under us */

        if (gDefaultConverter != NULL) {

            converter = gDefaultConverter;

            gDefaultConverter = NULL;

        }

        umtx_unlock(NULL);

    }

    /* if the cache was empty, create a converter */

    if(converter == NULL) {

        converter = ucnv_open(NULL, status);

        if(U_FAILURE(*status)) {

            ucnv_close(converter);

            converter = NULL;

        }

    }

    return converter;

}

U_CAPI void U_EXPORT2

u_releaseDefaultConverter(UConverter *converter)

{

    if(gDefaultConverter == NULL) {

        if (converter != NULL) {

            ucnv_reset(converter);

        }

        umtx_lock(NULL);

        if(gDefaultConverter == NULL) {

            gDefaultConverter = converter;

            converter = NULL;

        }

        umtx_unlock(NULL);

    }

    if(converter != NULL) {

        ucnv_close(converter);

    }

}

U_CAPI void U_EXPORT2

u_flushDefaultConverter()

{

    UConverter *converter = NULL;

    if (gDefaultConverter != NULL) {

        umtx_lock(NULL);

        /* need to check to make sure it wasn't taken out from under us */

        if (gDefaultConverter != NULL) {

            converter = gDefaultConverter;

            gDefaultConverter = NULL;

        }

        umtx_unlock(NULL);

    }

    /* if the cache was populated, flush it */

    if(converter != NULL) {

         ucnv_close(converter);

    }

}

/* conversions between char* and UChar* ------------------------------------- */

/* maximum string length for u_uastrcpy() and u_austrcpy() implementations */

#define MAX_STRLEN 0x0FFFFFFF

/*

 returns the minimum of (the length of the null-terminated string) and n.

*/

static int32_t u_astrnlen(const char *s1, int32_t n)

{

    int32_t len = 0;

    if (s1)

    {

        while (n-- && *(s1++))

        {

            len++;

        }

    }

    return len;

}

U_CAPI UChar*  U_EXPORT2

u_uastrncpy(UChar *ucs1,

           const char *s2,

           int32_t n)

{

  UChar *target = ucs1;

  UErrorCode err = U_ZERO_ERROR;

  UConverter *cnv = u_getDefaultConverter(&err);

  if(U_SUCCESS(err) && cnv != NULL) {

    ucnv_reset(cnv);

    ucnv_toUnicode(cnv,

                   &target,

                   ucs1+n,

                   &s2,

                   s2+u_astrnlen(s2, n),

                   NULL,

                   TRUE,

                   &err);

    ucnv_reset(cnv); /* be good citizens */

    u_releaseDefaultConverter(cnv);

    if(U_FAILURE(err) && (err != U_BUFFER_OVERFLOW_ERROR) ) {

      *ucs1 = 0; /* failure */

    }

    if(target < (ucs1+n)) { /* U_BUFFER_OVERFLOW_ERROR isn't an err, just means no termination will happen. */

      *target = 0;  /* terminate */

    }

  } else {

    *ucs1 = 0;

  }

  return ucs1;

}

U_CAPI UChar*  U_EXPORT2

u_uastrcpy(UChar *ucs1,

          const char *s2 )

{

  UErrorCode err = U_ZERO_ERROR;

  UConverter *cnv = u_getDefaultConverter(&err);

  if(U_SUCCESS(err) && cnv != NULL) {

    ucnv_toUChars(cnv,

                    ucs1,

                    MAX_STRLEN,

                    s2,

                    (int32_t)uprv_strlen(s2),

                    &err);

    u_releaseDefaultConverter(cnv);

    if(U_FAILURE(err)) {

      *ucs1 = 0;

    }

  } else {

    *ucs1 = 0;

  }

  return ucs1;

}

/*

 returns the minimum of (the length of the null-terminated string) and n.

*/

static int32_t u_ustrnlen(const UChar *ucs1, int32_t n)

{

    int32_t len = 0;

    if (ucs1)

    {

        while (n-- && *(ucs1++))

        {

            len++;

        }

    }

    return len;

}

U_CAPI char*  U_EXPORT2

u_austrncpy(char *s1,

        const UChar *ucs2,

        int32_t n)

{

  char *target = s1;

  UErrorCode err = U_ZERO_ERROR;

  UConverter *cnv = u_getDefaultConverter(&err);

  if(U_SUCCESS(err) && cnv != NULL) {

    ucnv_reset(cnv);

    ucnv_fromUnicode(cnv,

                  &target,

                  s1+n,

                  &ucs2,

                  ucs2+u_ustrnlen(ucs2, n),

                  NULL,

                  TRUE,

                  &err);

    ucnv_reset(cnv); /* be good citizens */

    u_releaseDefaultConverter(cnv);

    if(U_FAILURE(err) && (err != U_BUFFER_OVERFLOW_ERROR) ) {

      *s1 = 0; /* failure */

    }

    if(target < (s1+n)) { /* U_BUFFER_OVERFLOW_ERROR isn't an err, just means no termination will happen. */

      *target = 0;  /* terminate */

    }

  } else {

    *s1 = 0;

  }

  return s1;

}

U_CAPI char*  U_EXPORT2

u_austrcpy(char *s1,

         const UChar *ucs2 )

{

  UErrorCode err = U_ZERO_ERROR;

  UConverter *cnv = u_getDefaultConverter(&err);

  if(U_SUCCESS(err) && cnv != NULL) {

    int32_t len = ucnv_fromUChars(cnv,

                  s1,

                  MAX_STRLEN,

                  ucs2,

                  -1,

                  &err);

    u_releaseDefaultConverter(cnv);

    s1[len] = 0;

  } else {

    *s1 = 0;

  }

  return s1;

}

#endif