//
// String functions for libppd.
//
// Copyright © 2007-2019 by Apple Inc.
// Copyright © 1997-2007 by Easy Software Products.
//
// Licensed under Apache License v2.0.  See the file "LICENSE" for more
// information.
//

//
// Include necessary headers...
//

#define _PPD_STRING_C_
#include <ppd/string-private.h>
#include <ppd/array-private.h>
#include <ppd/thread-private.h>
#include <ppd/debug-internal.h>
#include <ppd/libcups2-private.h>
#include <stddef.h>
#include <limits.h>


//
// Local globals...
//

static _ppd_mutex_t	sp_mutex = _PPD_MUTEX_INITIALIZER;
					// Mutex to control access to pool
static cups_array_t	*stringpool = NULL;
					// Global string pool


//
// Local functions...
//

static int	ppd_compare_sp_items(_ppd_sp_item_t *a, _ppd_sp_item_t *b);


//
// '_ppdStrAlloc()' - Allocate/reference a string.
//

char *					// O - String pointer
_ppdStrAlloc(const char *s)		// I - String
{
  size_t		slen;		// Length of string
  _ppd_sp_item_t	*item,		// String pool item
			*key;		// Search key


  //
  // Range check input...
  //

  if (!s)
    return (NULL);

  //
  // Get the string pool...
  //

  _ppdMutexLock(&sp_mutex);

  if (!stringpool)
    stringpool = cupsArrayNew((cups_array_cb_t)ppd_compare_sp_items, NULL, NULL, 0, NULL, NULL);

  if (!stringpool)
  {
    _ppdMutexUnlock(&sp_mutex);

    return (NULL);
  }

  //
  // See if the string is already in the pool...
  //

  key = (_ppd_sp_item_t *)(s - offsetof(_ppd_sp_item_t, str));

  if ((item = (_ppd_sp_item_t *)cupsArrayFind(stringpool, key)) != NULL)
  {
    //
    // Found it, return the cached string...
    //

    item->ref_count ++;

#ifdef DEBUG_GUARDS
    DEBUG_printf(("5_ppdStrAlloc: Using string %p(%s) for \"%s\", guard=%08x, "
                  "ref_count=%d", item, item->str, s, item->guard,
		  item->ref_count));

    if (item->guard != _PPD_STR_GUARD)
    {
      _ppdMutexUnlock(&sp_mutex);
      abort();
    }
#endif // DEBUG_GUARDS

    _ppdMutexUnlock(&sp_mutex);

    return (item->str);
  }

  //
  // Not found, so allocate a new one...
  //

  slen = strlen(s);
  item = (_ppd_sp_item_t *)calloc(1, sizeof(_ppd_sp_item_t) + slen);
  if (!item)
  {
    _ppdMutexUnlock(&sp_mutex);

    return (NULL);
  }

  item->ref_count = 1;
  memcpy(item->str, s, slen + 1);

#ifdef DEBUG_GUARDS
  item->guard = _PPD_STR_GUARD;

  DEBUG_printf(("5_ppdStrAlloc: Created string %p(%s) for \"%s\", guard=%08x, "
		"ref_count=%d", item, item->str, s, item->guard,
		item->ref_count));
#endif // DEBUG_GUARDS

  //
  // Add the string to the pool and return it...
  //

  cupsArrayAdd(stringpool, item);

  _ppdMutexUnlock(&sp_mutex);

  return (item->str);
}


//
// '_ppdStrFlush()' - Flush the string pool.
//

void
_ppdStrFlush(void)
{
  _ppd_sp_item_t	*item;		// Current item


  DEBUG_printf(("4_ppdStrFlush: %d strings in array",
                cupsArrayGetCount(stringpool)));

  _ppdMutexLock(&sp_mutex);

  for (item = (_ppd_sp_item_t *)cupsArrayGetFirst(stringpool);
       item;
       item = (_ppd_sp_item_t *)cupsArrayGetNext(stringpool))
    free(item);

  cupsArrayDelete(stringpool);
  stringpool = NULL;

  _ppdMutexUnlock(&sp_mutex);
}


//
// '_ppdStrFormatd()' - Format a floating-point number.
//

char *					// O - Pointer to end of string
_ppdStrFormatd(char         *buf,	// I - String
                char         *bufend,	// I - End of string buffer
		double       number,	// I - Number to format
                struct lconv *loc)	// I - Locale data
{
  char		*bufptr,		// Pointer into buffer
		temp[1024],		// Temporary string
		*tempdec,		// Pointer to decimal point
		*tempptr;		// Pointer into temporary string
  const char	*dec;			// Decimal point
  int		declen;			// Length of decimal point


  //
  // Format the number using the "%.12f" format and then eliminate
  // unnecessary trailing 0's.
  //

  snprintf(temp, sizeof(temp), "%.12f", number);
  for (tempptr = temp + strlen(temp) - 1;
       tempptr > temp && *tempptr == '0';
       *tempptr-- = '\0');

  //
  // Next, find the decimal point...
  //

  if (loc && loc->decimal_point)
  {
    dec    = loc->decimal_point;
    declen = (int)strlen(dec);
  }
  else
  {
    dec    = ".";
    declen = 1;
  }

  if (declen == 1)
    tempdec = strchr(temp, *dec);
  else
    tempdec = strstr(temp, dec);

  //
  // Copy everything up to the decimal point...
  //

  if (tempdec)
  {
    for (tempptr = temp, bufptr = buf;
         tempptr < tempdec && bufptr < bufend;
	 *bufptr++ = *tempptr++);

    tempptr += declen;

    if (*tempptr && bufptr < bufend)
    {
      *bufptr++ = '.';

      while (*tempptr && bufptr < bufend)
        *bufptr++ = *tempptr++;
    }

    *bufptr = '\0';
  }
  else
  {
    strlcpy(buf, temp, (size_t)(bufend - buf + 1));
    bufptr = buf + strlen(buf);
  }

  return (bufptr);
}


//
// '_ppdStrFree()' - Free/dereference a string.
//

void
_ppdStrFree(const char *s)		// I - String to free
{
  _ppd_sp_item_t	*item,		// String pool item
			*key;		// Search key


  //
  // Range check input...
  //

  if (!s)
    return;

  //
  // Check the string pool...
  //
  // We don't need to lock the mutex yet, as we only want to know if
  // the stringpool is initialized.  The rest of the code will still
  // work if it is initialized before we lock...
  //

  if (!stringpool)
    return;

  //
  // See if the string is already in the pool...
  //

  _ppdMutexLock(&sp_mutex);

  key = (_ppd_sp_item_t *)(s - offsetof(_ppd_sp_item_t, str));

  if ((item = (_ppd_sp_item_t *)cupsArrayFind(stringpool, key)) != NULL &&
      item == key)
  {
    //
    // Found it, dereference...
    //

#ifdef DEBUG_GUARDS
    if (key->guard != _PPD_STR_GUARD)
    {
      DEBUG_printf(("5_ppdStrFree: Freeing string %p(%s), guard=%08x, ref_count=%d", key, key->str, key->guard, key->ref_count));
      _ppdMutexUnlock(&sp_mutex);
      abort();
    }
#endif // DEBUG_GUARDS

    item->ref_count --;

    if (!item->ref_count)
    {
      //
      // Remove and free...
      //

      cupsArrayRemove(stringpool, item);

      free(item);
    }
  }

  _ppdMutexUnlock(&sp_mutex);
}


//
// '_ppdStrRetain()' - Increment the reference count of a string.
//
// Note: This function does not verify that the passed pointer is in the
//       string pool, so any calls to it MUST know they are passing in a
//       good pointer.
//

char *					// O - Pointer to string
_ppdStrRetain(const char *s)		// I - String to retain
{
  _ppd_sp_item_t	*item;		// Pointer to string pool item


  if (s)
  {
    item = (_ppd_sp_item_t *)(s - offsetof(_ppd_sp_item_t, str));

#ifdef DEBUG_GUARDS
    if (item->guard != _PPD_STR_GUARD)
    {
      DEBUG_printf(("5_ppdStrRetain: Retaining string %p(%s), guard=%08x, "
                    "ref_count=%d", item, s, item->guard, item->ref_count));
      abort();
    }
#endif // DEBUG_GUARDS

    _ppdMutexLock(&sp_mutex);

    item->ref_count ++;

    _ppdMutexUnlock(&sp_mutex);
  }

  return ((char *)s);
}


//
// '_ppdStrScand()' - Scan a string for a floating-point number.
//
// This function handles the locale-specific BS so that a decimal
// point is always the period (".")...
//

double					// O - Number
_ppdStrScand(const char   *buf,		// I - Pointer to number
	     char         **bufptr,	// O - New pointer or NULL on error
	     struct lconv *loc)		// I - Locale data
{
  char	temp[1024],			// Temporary buffer
	*tempptr;			// Pointer into temporary buffer


  //
  // Range check input...
  //

  if (!buf)
    return (0.0);

  //
  // Skip leading whitespace...
  //

  while (_ppd_isspace(*buf))
    buf ++;

  //
  // Copy leading sign, numbers, period, and then numbers...
  //

  tempptr = temp;
  if (*buf == '-' || *buf == '+')
    *tempptr++ = *buf++;

  while (isdigit(*buf & 255))
    if (tempptr < (temp + sizeof(temp) - 1))
      *tempptr++ = *buf++;
    else
    {
      if (bufptr)
	*bufptr = NULL;

      return (0.0);
    }

  if (*buf == '.')
  {
    //
    // Read fractional portion of number...
    //

    buf ++;

    if (loc && loc->decimal_point)
    {
      strlcpy(tempptr, loc->decimal_point,
	      sizeof(temp) - (size_t)(tempptr - temp));
      tempptr += strlen(tempptr);
    }
    else if (tempptr < (temp + sizeof(temp) - 1))
      *tempptr++ = '.';
    else
    {
      if (bufptr)
        *bufptr = NULL;

      return (0.0);
    }

    while (isdigit(*buf & 255))
      if (tempptr < (temp + sizeof(temp) - 1))
	*tempptr++ = *buf++;
      else
      {
	if (bufptr)
	  *bufptr = NULL;

	return (0.0);
      }
  }

  if (*buf == 'e' || *buf == 'E')
  {
    //
    // Read exponent...
    //

    if (tempptr < (temp + sizeof(temp) - 1))
      *tempptr++ = *buf++;
    else
    {
      if (bufptr)
	*bufptr = NULL;

      return (0.0);
    }

    if (*buf == '+' || *buf == '-')
    {
      if (tempptr < (temp + sizeof(temp) - 1))
	*tempptr++ = *buf++;
      else
      {
	if (bufptr)
	  *bufptr = NULL;

	return (0.0);
      }
    }

    while (isdigit(*buf & 255))
      if (tempptr < (temp + sizeof(temp) - 1))
	*tempptr++ = *buf++;
      else
      {
	if (bufptr)
	  *bufptr = NULL;

	return (0.0);
      }
  }

  //
  // Nul-terminate the temporary string and return the value...
  //

  if (bufptr)
    *bufptr = (char *)buf;

  *tempptr = '\0';

  return (atof(temp));
}


//
// '_ppdStrStatistics()' - Return allocation statistics for string pool.
//

size_t					// O - Number of strings
_ppdStrStatistics(size_t *alloc_bytes,	// O - Allocated bytes
		  size_t *total_bytes)	// O - Total string bytes
{
  size_t		count,		// Number of strings
			abytes,		// Allocated string bytes
			tbytes,		// Total string bytes
			len;		// Length of string
  _ppd_sp_item_t	*item;		// Current item


  //
  // Loop through strings in pool, counting everything up...
  //

  _ppdMutexLock(&sp_mutex);

  for (count = 0, abytes = 0, tbytes = 0,
	 item = (_ppd_sp_item_t *)cupsArrayGetFirst(stringpool);
       item;
       item = (_ppd_sp_item_t *)cupsArrayGetNext(stringpool))
  {
    //
    // Count allocated memory, using a 64-bit aligned buffer as a basis.
    //

    count  += item->ref_count;
    len    = (strlen(item->str) + 8) & (size_t)~7;
    abytes += sizeof(_ppd_sp_item_t) + len;
    tbytes += item->ref_count * len;
  }

  _ppdMutexUnlock(&sp_mutex);

  //
  // Return values...
  //

  if (alloc_bytes)
    *alloc_bytes = abytes;

  if (total_bytes)
    *total_bytes = tbytes;

  return (count);
}


//
// '_ppd_strcpy()' - Copy a string allowing for overlapping strings.
//

void
_ppd_strcpy(char       *dst,		// I - Destination string
	    const char *src)		// I - Source string
{
  while (*src)
    *dst++ = *src++;

  *dst = '\0';
}


//
// '_ppd_strdup()' - Duplicate a string.
//

#ifndef HAVE_STRDUP
char 	*				// O - New string pointer
_ppd_strdup(const char *s)		// I - String to duplicate
{
  char		*t;			// New string pointer
  size_t	slen;			// Length of string


  if (!s)
    return (NULL);

  slen = strlen(s);
  if ((t = malloc(slen + 1)) == NULL)
    return (NULL);

  return (memcpy(t, s, slen + 1));
}
#endif // !HAVE_STRDUP


//
// '_ppd_strcasecmp()' - Do a case-insensitive comparison.
//

int				// O - Result of comparison (-1, 0, or 1)
_ppd_strcasecmp(const char *s,	// I - First string
		const char *t)	// I - Second string
{
  while (*s != '\0' && *t != '\0')
  {
    if (_ppd_tolower(*s) < _ppd_tolower(*t))
      return (-1);
    else if (_ppd_tolower(*s) > _ppd_tolower(*t))
      return (1);

    s ++;
    t ++;
  }

  if (*s == '\0' && *t == '\0')
    return (0);
  else if (*s != '\0')
    return (1);
  else
    return (-1);
}


//
// '_ppd_strncasecmp()' - Do a case-insensitive comparison on up to N chars.
//

int					// O - Result of comparison
					//     (-1, 0, or 1)
_ppd_strncasecmp(const char *s,		// I - First string
		 const char *t,		// I - Second string
		 size_t     n)		// I - Maximum number of characters to
					//     compare
{
  while (*s != '\0' && *t != '\0' && n > 0)
  {
    if (_ppd_tolower(*s) < _ppd_tolower(*t))
      return (-1);
    else if (_ppd_tolower(*s) > _ppd_tolower(*t))
      return (1);

    s ++;
    t ++;
    n --;
  }

  if (n == 0)
    return (0);
  else if (*s == '\0' && *t == '\0')
    return (0);
  else if (*s != '\0')
    return (1);
  else
    return (-1);
}


#ifndef HAVE_STRLCAT
//
// '_ppd_strlcat()' - Safely concatenate two strings.
//

size_t					// O - Length of string
_ppd_strlcat(char       *dst,		// O - Destination string
	     const char *src,		// I - Source string
	     size_t     size)		// I - Size of destination string buffer
{
  size_t	srclen;			// Length of source string
  size_t	dstlen;			// Length of destination string


  //
  // Figure out how much room is left...
  //

  dstlen = strlen(dst);

  if (size < (dstlen + 1))
    return (dstlen);		        // No room, return immediately...

  size -= dstlen + 1;

  //
  // Figure out how much room is needed...
  //

  srclen = strlen(src);

  //
  // Copy the appropriate amount...
  //

  if (srclen > size)
    srclen = size;

  memmove(dst + dstlen, src, srclen);
  dst[dstlen + srclen] = '\0';

  return (dstlen + srclen);
}
#endif // !HAVE_STRLCAT


#ifndef HAVE_STRLCPY
//
// '_ppd_strlcpy()' - Safely copy two strings.
//

size_t					// O - Length of string
_ppd_strlcpy(char       *dst,		// O - Destination string
	     const char *src,		// I - Source string
	     size_t      size)		// I - Size of destination string buffer
{
  size_t	srclen;			// Length of source string


  if (size == 0)
    return (0);

  //
  // Figure out how much room is needed...
  //

  size --;

  srclen = strlen(src);

  //
  // Copy the appropriate amount...
  //

  if (srclen > size)
    srclen = size;

  memmove(dst, src, srclen);
  dst[srclen] = '\0';

  return (srclen);
}
#endif // !HAVE_STRLCPY


//
// 'ppd_compare_sp_items()' - Compare two string pool items...
//

static int				// O - Result of comparison
ppd_compare_sp_items(_ppd_sp_item_t *a,	// I - First item
		     _ppd_sp_item_t *b)	// I - Second item
{
  return (strcmp(a->str, b->str));
}