triostr.c

一个C语言写的快速贝叶斯垃圾邮件过滤工具

/*************************************************************************
 *
 * $Id: triostr.c,v 1.30 2005/11/26 14:47:54 breese Exp $
 *
 * Copyright (C) 2001 Bjorn Reese and Daniel Stenberg.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE AUTHORS AND
 * CONTRIBUTORS ACCEPT NO RESPONSIBILITY IN ANY CONCEIVABLE MANNER.
 *
 ************************************************************************/

/*************************************************************************
 * Include files
 */

#if defined(HAVE_CONFIG_H)
# include <config.h>
#endif
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include "triodef.h"
#include "triostr.h"
#if defined(TRIO_FUNC_TO_LONG_DOUBLE)
# define USE_MATH
#endif
#if defined(USE_MATH)
# include <math.h>
#endif

/*************************************************************************
 * Definitions
 */

#if !defined(TRIO_PUBLIC_STRING)
# define TRIO_PUBLIC_STRING TRIO_PUBLIC
#endif
#if !defined(TRIO_PRIVATE_STRING)
# define TRIO_PRIVATE_STRING TRIO_PRIVATE
#endif

#if !defined(NULL)
# define NULL 0
#endif
#if !defined(NIL)
# define NIL ((char)0)
#endif
#if !defined(FALSE)
# define FALSE (1 == 0)
# define TRUE (! FALSE)
#endif
#if !defined(BOOLEAN_T)
# define BOOLEAN_T int
#endif

#if defined(USE_MATH)
# if defined(PREDEF_STANDARD_C99)
#  if defined(TRIO_COMPILER_DECC)
#   if (TRIO_COMPILER_DECC - 0 > 80000000)
/*
 * The OSF/1 runtime that comes with the DECC compiler does not support
 * hexfloats conversion.
 */
#    define USE_STRTOD
#    define USE_STRTOF
#   endif
#  else
#   define USE_STRTOD
#   define USE_STRTOF
#  endif
# else
#  if defined(TRIO_COMPILER_VISUALC)
#   define USE_STRTOD
#  endif
#endif
#endif

#if defined(TRIO_PLATFORM_UNIX)
# if defined(PREDEF_STANDARD_UNIX95)
#  define USE_STRCASECMP
#  define USE_STRNCASECMP
# endif
# if defined(TRIO_PLATFORM_SUNOS)
#  define USE_SYS_ERRLIST
# else
#  define USE_STRERROR
# endif
# if defined(TRIO_PLATFORM_QNX)
#  define strcasecmp(x,y) stricmp(x,y)
#  define strncasecmp(x,y,n) strnicmp(x,y,n)
# endif
#endif

#if defined(TRIO_PLATFORM_WIN32)
# define USE_STRCASECMP
# define strcasecmp(x,y) strcmpi(x,y)
#endif

#if !(defined(TRIO_PLATFORM_SUNOS))
# define USE_TOLOWER
# define USE_TOUPPER
#endif

#if defined(USE_MATH)
# if !defined(HAVE_POWL)
#  if defined(PREDEF_STANDARD_C99) \
   || defined(PREDEF_STANDARD_UNIX03)
#   define HAVE_POWL
#  else
#   if defined(TRIO_COMPILER_VISUALC)
#    if defined(powl)
#     define HAVE_POWL
#    endif
#   endif
#  endif
# endif
#endif

#if defined(HAVE_POWL)
# define trio_powl(x,y) powl((x),(y))
#else
# define trio_powl(x,y) pow((double)(x),(double)(y))
#endif

#if defined(TRIO_FUNC_TO_UPPER) \
 || (defined(TRIO_FUNC_EQUAL) && !defined(USE_STRCASECMP)) \
 || (defined(TRIO_FUNC_EQUAL_MAX) && !defined(USE_STRNCASECMP)) \
 || defined(TRIO_FUNC_MATCH) \
 || defined(TRIO_FUNC_TO_LONG_DOUBLE) \
 || defined(TRIO_FUNC_UPPER)
# define TRIO_FUNC_INTERNAL_TO_UPPER
#endif

/*************************************************************************
 * Structures
 */

struct _trio_string_t
{
  char *content;
  size_t length;
  size_t allocated;
};

/*************************************************************************
 * Constants
 */

#if !defined(TRIO_EMBED_STRING)
static TRIO_CONST char rcsid[] = "@(#)$Id: triostr.c,v 1.30 2005/11/26 14:47:54 breese Exp $";
#endif

/*************************************************************************
 * Static String Functions
 */

#if defined(TRIO_DOCUMENTATION)
# include "doc/doc_static.h"
#endif
/** @addtogroup StaticStrings
    @{
*/

/*
 * internal_duplicate_max
 */
#if defined(TRIO_FUNC_DUPLICATE) \
 || defined(TRIO_FUNC_DUPLICATE_MAX) \
 || defined(TRIO_FUNC_STRING_DUPLICATE) \
 || defined(TRIO_FUNC_XSTRING_DUPLICATE)

TRIO_PRIVATE_STRING char *
internal_duplicate_max
TRIO_ARGS2((source, size),
	   TRIO_CONST char *source,
	   size_t size)
{
  char *target;

  assert(source);

  /* Make room for string plus a terminating zero */
  size++;
  target = trio_create(size);
  if (target)
    {
      trio_copy_max(target, size, source);
    }
  return target;
}

#endif

/*
 * internal_string_alloc
 */
#if defined(TRIO_FUNC_STRING_CREATE) \
 || defined(TRIO_FUNC_STRING_DUPLICATE) \
 || defined(TRIO_FUNC_XSTRING_DUPLICATE)

TRIO_PRIVATE_STRING trio_string_t *
internal_string_alloc(TRIO_NOARGS)
{
  trio_string_t *self;
  
  self = (trio_string_t *)TRIO_MALLOC(sizeof(trio_string_t));
  if (self)
    {
      self->content = NULL;
      self->length = 0;
      self->allocated = 0;
    }
  return self;
}

#endif

/*
 * internal_string_grow
 *
 * The size of the string will be increased by 'delta' characters. If
 * 'delta' is zero, the size will be doubled.
 */
#if defined(TRIO_FUNC_STRING_CREATE) \
 || defined(TRIO_FUNC_STRING_APPEND) \
 || defined(TRIO_FUNC_XSTRING_APPEND) \
 || defined(TRIO_FUNC_XSTRING_APPEND_CHAR)

TRIO_PRIVATE_STRING BOOLEAN_T
internal_string_grow
TRIO_ARGS2((self, delta),
	   trio_string_t *self,
	   size_t delta)
{
  BOOLEAN_T status = FALSE;
  char *new_content;
  size_t new_size;

  new_size = (delta == 0)
    ? ( (self->allocated == 0) ? 1 : self->allocated * 2 )
    : self->allocated + delta;
  
  new_content = (char *)TRIO_REALLOC(self->content, new_size);
  if (new_content)
    {
      self->content = new_content;
      self->allocated = new_size;
      status = TRUE;
    }
  return status;
}

#endif

/*
 * internal_string_grow_to
 *
 * The size of the string will be increased to 'length' plus one characters.
 * If 'length' is less than the original size, the original size will be
 * used (that is, the size of the string is never decreased).
 */
#if defined(TRIO_FUNC_STRING_APPEND) \
 || defined(TRIO_FUNC_XSTRING_APPEND)

TRIO_PRIVATE_STRING BOOLEAN_T
internal_string_grow_to
TRIO_ARGS2((self, length),
	   trio_string_t *self,
	   size_t length)
{
  length++; /* Room for terminating zero */
  return (self->allocated < length)
    ? internal_string_grow(self, length - self->allocated)
    : TRUE;
}

#endif

#if defined(TRIO_FUNC_INTERNAL_TO_UPPER)

TRIO_PRIVATE_STRING TRIO_INLINE int
internal_to_upper
TRIO_ARGS1((source),
	   int source)
{
# if defined(USE_TOUPPER)
  
  return toupper(source);
  
# else

  /* Does not handle locales or non-contiguous alphabetic characters */
  return ((source >= (int)'a') && (source <= (int)'z'))
    ? source - 'a' + 'A'
    : source;
  
# endif
}

#endif


/**
   Create new string.

   @param size Size of new string.
   @return Pointer to string, or NULL if allocation failed.
*/
#if defined(TRIO_FUNC_CREATE)

TRIO_PUBLIC_STRING char *
trio_create
TRIO_ARGS1((size),
	   size_t size)
{
  return (char *)TRIO_MALLOC(size);
}

#endif

/**
   Destroy string.

   @param string String to be freed.
*/
#if defined(TRIO_FUNC_DESTROY)

TRIO_PUBLIC_STRING void
trio_destroy
TRIO_ARGS1((string),
	   char *string)
{
  if (string)
    {
      TRIO_FREE(string);
    }
}

#endif

/**
   Count the number of characters in a string.

   @param string String to measure.
   @return Number of characters in @p string.
*/
#if defined(TRIO_FUNC_LENGTH)

TRIO_PUBLIC_STRING size_t
trio_length
TRIO_ARGS1((string),
	   TRIO_CONST char *string)
{
  return strlen(string);
}

#endif

/**
   Append @p source at the end of @p target.
   
   @param target Target string.
   @param source Source string.
   @return Boolean value indicating success or failure.
   
   @pre @p target must point to a memory chunk with sufficient room to
   contain the @p target string and @p source string.
   @pre No boundary checking is performed, so insufficient memory will
   result in a buffer overrun.
   @post @p target will be zero terminated.
*/
#if defined(TRIO_FUNC_APPEND)

TRIO_PUBLIC_STRING int
trio_append
TRIO_ARGS2((target, source),
	   char *target,
	   TRIO_CONST char *source)
{
  assert(target);
  assert(source);
  
  return (strcat(target, source) != NULL);
}

#endif

/**
   Append at most @p max characters from @p source to @p target.
   
   @param target Target string.
   @param max Maximum number of characters to append.
   @param source Source string.
   @return Boolean value indicating success or failure.
   
   @pre @p target must point to a memory chuck with sufficient room to
   contain the @p target string and the @p source string (at most @p max
   characters).
   @pre No boundary checking is performed, so insufficient memory will
   result in a buffer overrun.
   @post @p target will be zero terminated.
*/
#if defined(TRIO_FUNC_APPEND_MAX)

TRIO_PUBLIC_STRING int
trio_append_max
TRIO_ARGS3((target, max, source),
	   char *target,
	   size_t max,
	   TRIO_CONST char *source)
{
  size_t length;
  
  assert(target);
  assert(source);

  length = trio_length(target);
  
  if (max > length)
    {
      strncat(target, source, max - length - 1);
    }
  return TRUE;
}

#endif

/**
   Determine if a string contains a substring.

   @param string String to be searched.
   @param substring String to be found.
   @return Boolean value indicating success or failure.
*/
#if defined(TRIO_FUNC_CONTAINS)

TRIO_PUBLIC_STRING int
trio_contains
TRIO_ARGS2((string, substring),
	   TRIO_CONST char *string,
	   TRIO_CONST char *substring)
{
  assert(string);
  assert(substring);
  
  return (0 != strstr(string, substring));
}

#endif

/**
   Copy @p source to @p target.
   
   @param target Target string.
   @param source Source string.
   @return Boolean value indicating success or failure.
   
   @pre @p target must point to a memory chunk with sufficient room to
   contain the @p source string.
   @pre No boundary checking is performed, so insufficient memory will
   result in a buffer overrun.
   @post @p target will be zero terminated.
*/
#if defined(TRIO_FUNC_COPY)

TRIO_PUBLIC_STRING int
trio_copy
TRIO_ARGS2((target, source),
	   char *target,
	   TRIO_CONST char *source)
{
  assert(target);
  assert(source);
     
  (void)strcpy(target, source);
  return TRUE;
}

#endif

/**
   Copy at most @p max characters from @p source to @p target.
   
   @param target Target string.
   @param max Maximum number of characters to append.
   @param source Source string.
   @return Boolean value indicating success or failure.
   
   @pre @p target must point to a memory chunk with sufficient room to
   contain the @p source string (at most @p max characters).
   @pre No boundary checking is performed, so insufficient memory will
   result in a buffer overrun.
   @post @p target will be zero terminated.
*/
#if defined(TRIO_FUNC_COPY_MAX)

TRIO_PUBLIC_STRING int
trio_copy_max
TRIO_ARGS3((target, max, source),
	   char *target,
	   size_t max,
	   TRIO_CONST char *source)
{
  assert(target);
  assert(source);
  assert(max > 0); /* Includes != 0 */

  (void)strncpy(target, source, max - 1);
  target[max - 1] = (char)0;
  return TRUE;
}

#endif

/**
   Duplicate @p source.
   
   @param source Source string.
   @return A copy of the @p source string.
   
   @post @p target will be zero terminated.
*/
#if defined(TRIO_FUNC_DUPLICATE)

TRIO_PUBLIC_STRING char *
trio_duplicate
TRIO_ARGS1((source),
	   TRIO_CONST char *source)
{
  return internal_duplicate_max(source, trio_length(source));
}

#endif

/**
   Duplicate at most @p max characters of @p source.
   
   @param source Source string.
   @param max Maximum number of characters to duplicate.
   @return A copy of the @p source string.
   
   @post @p target will be zero terminated.
*/
#if defined(TRIO_FUNC_DUPLICATE_MAX)

TRIO_PUBLIC_STRING char *
trio_duplicate_max
TRIO_ARGS2((source, max),
	   TRIO_CONST char *source,
	   size_t max)
{
  size_t length;

  assert(source);
  assert(max > 0);

  length = trio_length(source);
  if (length > max)
    {
      length = max;
    }
  return internal_duplicate_max(source, length);
}

#endif

/**
   Compare if two strings are equal.
   
   @param first First string.
   @param second Second string.
   @return Boolean indicating whether the two strings are equal or not.
   
   Case-insensitive comparison.
*/
#if defined(TRIO_FUNC_EQUAL)

TRIO_PUBLIC_STRING int
trio_equal
TRIO_ARGS2((first, second),
	   TRIO_CONST char *first,
	   TRIO_CONST char *second)
{
  assert(first);
  assert(second);

  if ((first != NULL) && (second != NULL))
    {
# if defined(USE_STRCASECMP)
      return (0 == strcasecmp(first, second));
# else
      while ((*first != NIL) && (*second != NIL))
	{
	  if (internal_to_upper(*first) != internal_to_upper(*second))
	    {
	      break;
	    }
	  first++;
	  second++;
	}
      return ((*first == NIL) && (*second == NIL));
# endif
    }
  return FALSE;
}

#endif

/**
   Compare if two strings are equal.
   
   @param first First string.
   @param second Second string.
   @return Boolean indicating whether the two strings are equal or not.
   
   Case-sensitive comparison.
*/
#if defined(TRIO_FUNC_EQUAL_CASE)

TRIO_PUBLIC_STRING int
trio_equal_case
TRIO_ARGS2((first, second),
	   TRIO_CONST char *first,
	   TRIO_CONST char *second)
{
  assert(first);
  assert(second);

  if ((first != NULL) && (second != NULL))
    {
      return (0 == strcmp(first, second));
    }
  return FALSE;
}

#endif

/**
   Compare if two strings up until the first @p max characters are equal.
   
   @param first First string.
   @param max Maximum number of characters to compare.
   @param second Second string.
   @return Boolean indicating whether the two strings are equal or not.
   
   Case-sensitive comparison.
*/
#if defined(TRIO_FUNC_EQUAL_CASE_MAX)

TRIO_PUBLIC_STRING int
trio_equal_case_max
TRIO_ARGS3((first, max, second),
	   TRIO_CONST char *first,
	   size_t max,
	   TRIO_CONST char *second)
{
  assert(first);
  assert(second);

  if ((first != NULL) && (second != NULL))
    {
      return (0 == strncmp(first, second, max));
    }
  return FALSE;
}

#endif

/**
   Compare if two strings are equal.
   
   @param first First string.
   @param second Second string.
   @return Boolean indicating whether the two strings are equal or not.

   Collating characters are considered equal.
*/
#if defined(TRIO_FUNC_EQUAL_LOCALE)

TRIO_PUBLIC_STRING int
trio_equal_locale
TRIO_ARGS2((first, second),
	   TRIO_CONST char *first,
	   TRIO_CONST char *second)
{
  assert(first);
  assert(second);

# if defined(LC_COLLATE)
  return (strcoll(first, second) == 0);
# else
  return trio_equal(first, second);
# endif
}

#endif

/**
   Compare if two strings up until the first @p max characters are equal.
   
   @param first First string.
   @param max Maximum number of characters to compare.
   @param second Second string.
   @return Boolean indicating whether the two strings are equal or not.
   
   Case-insensitive comparison.
*/
#if defined(TRIO_FUNC_EQUAL_MAX)

TRIO_PUBLIC_STRING int
trio_equal_max
TRIO_ARGS3((first, max, second),
	   TRIO_CONST char *first,
	   size_t max,
	   TRIO_CONST char *second)
{
  assert(first);
  assert(second);

  if ((first != NULL) && (second != NULL))
    {
# if defined(USE_STRNCASECMP)
      return (0 == strncasecmp(first, second, max));
# else
      /* Not adequately tested yet */
      size_t cnt = 0;
      while ((*first != NIL) && (*second != NIL) && (cnt <= max))
	{
	  if (internal_to_upper(*first) != internal_to_upper(*second))
	    {
	      break;
	    }
	  first++;
	  second++;
	  cnt++;
	}
      return ((cnt == max) || ((*first == NIL) && (*second == NIL)));
# endif
    }
  return FALSE;
}

#endif

/**
   Provide a textual description of an error code (errno).

   @param error_number Error number.
   @return Textual description of @p error_number.
*/
#if defined(TRIO_FUNC_ERROR)

TRIO_PUBLIC_STRING TRIO_CONST char *
trio_error
TRIO_ARGS1((error_number),
	   int error_number)
{
# if defined(USE_STRERROR)
  
  return strerror(error_number);

# else
#  if defined(USE_SYS_ERRLIST)