OpenTTD-patches/src/string_func.h
2019-05-23 22:53:17 +01:00

280 lines
8.3 KiB
C++

/* $Id$ */
/*
* This file is part of OpenTTD.
* OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
* OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file string_func.h Functions related to low-level strings.
*
* @note Be aware of "dangerous" string functions; string functions that
* have behaviour that could easily cause buffer overruns and such:
* - strncpy: does not '\0' terminate when input string is longer than
* the size of the output string. Use strecpy instead.
* - [v]snprintf: returns the length of the string as it would be written
* when the output is large enough, so it can be more than the size of
* the buffer and than can underflow size_t (uint-ish) which makes all
* subsequent snprintf alikes write outside of the buffer. Use
* [v]seprintf instead; it will return the number of bytes actually
* added so no [v]seprintf will cause outside of bounds writes.
* - [v]sprintf: does not bounds checking: use [v]seprintf instead.
*/
#ifndef STRING_FUNC_H
#define STRING_FUNC_H
#include <stdarg.h>
#include "core/bitmath_func.hpp"
#include "string_type.h"
char *strecat(char *dst, const char *src, const char *last);
char *strecpy(char *dst, const char *src, const char *last, bool quiet_mode = false);
char *stredup(const char *src, const char *last = nullptr);
int CDECL seprintf(char *str, const char *last, const char *format, ...) WARN_FORMAT(3, 4);
int CDECL vseprintf(char *str, const char *last, const char *format, va_list ap);
char *CDECL str_fmt(const char *str, ...) WARN_FORMAT(1, 2);
char *str_vfmt(const char *str, va_list ap);
std::string CDECL stdstr_fmt(const char *str, ...) WARN_FORMAT(1, 2);
std::string stdstr_vfmt(const char *str, va_list va);
char *str_validate_intl(char *str, const char *last, StringValidationSettings settings);
/**
* Scans the string for valid characters and if it finds invalid ones,
* replaces them with a question mark '?' (if not ignored)
* @param str the string to validate
* @param last the last valid character of str
* @param settings the settings for the string validation.
*/
static inline void str_validate(char *str, const char *last, StringValidationSettings settings = SVS_REPLACE_WITH_QUESTION_MARK)
{
*str_validate_intl(str, last, settings) = '\0';
}
void ValidateString(const char *str);
void str_fix_scc_encoded(char *str, const char *last);
void str_strip_colours(char *str);
char *str_replace_wchar(char *str, const char *last, WChar find, WChar replace);
bool strtolower(char *str);
bool StrValid(const char *str, const char *last);
/**
* Check if a string buffer is empty.
*
* @param s The pointer to the first element of the buffer
* @return true if the buffer starts with the terminating null-character or
* if the given pointer points to nullptr else return false
*/
static inline bool StrEmpty(const char *s)
{
return s == nullptr || s[0] == '\0';
}
/**
* Get the length of a string, within a limited buffer.
*
* @param str The pointer to the first element of the buffer
* @param maxlen The maximum size of the buffer
* @return The length of the string
*/
static inline size_t ttd_strnlen(const char *str, size_t maxlen)
{
const char *t;
for (t = str; (size_t)(t - str) < maxlen && *t != '\0'; t++) {}
return t - str;
}
char *md5sumToString(char *buf, const char *last, const uint8 md5sum[16]);
bool IsValidChar(WChar key, CharSetFilter afilter);
size_t Utf8Decode(WChar *c, const char *s);
size_t Utf8Encode(char *buf, WChar c);
size_t Utf8TrimString(char *s, size_t maxlen);
static inline WChar Utf8Consume(const char **s)
{
WChar c;
*s += Utf8Decode(&c, *s);
return c;
}
/**
* Return the length of a UTF-8 encoded character.
* @param c Unicode character.
* @return Length of UTF-8 encoding for character.
*/
static inline int8 Utf8CharLen(WChar c)
{
if (c < 0x80) return 1;
if (c < 0x800) return 2;
if (c < 0x10000) return 3;
if (c < 0x110000) return 4;
/* Invalid valid, we encode as a '?' */
return 1;
}
/**
* Return the length of an UTF-8 encoded value based on a single char. This
* char should be the first byte of the UTF-8 encoding. If not, or encoding
* is invalid, return value is 0
* @param c char to query length of
* @return requested size
*/
static inline int8 Utf8EncodedCharLen(char c)
{
if (GB(c, 3, 5) == 0x1E) return 4;
if (GB(c, 4, 4) == 0x0E) return 3;
if (GB(c, 5, 3) == 0x06) return 2;
if (GB(c, 7, 1) == 0x00) return 1;
/* Invalid UTF8 start encoding */
return 0;
}
/* Check if the given character is part of a UTF8 sequence */
static inline bool IsUtf8Part(char c)
{
return GB(c, 6, 2) == 2;
}
/**
* Retrieve the previous UNICODE character in an UTF-8 encoded string.
* @param s char pointer pointing to (the first char of) the next character
* @return a pointer in 's' to the previous UNICODE character's first byte
* @note The function should not be used to determine the length of the previous
* encoded char because it might be an invalid/corrupt start-sequence
*/
static inline char *Utf8PrevChar(char *s)
{
char *ret = s;
while (IsUtf8Part(*--ret)) {}
return ret;
}
static inline const char *Utf8PrevChar(const char *s)
{
const char *ret = s;
while (IsUtf8Part(*--ret)) {}
return ret;
}
size_t Utf8StringLength(const char *s);
/**
* Is the given character a lead surrogate code point?
* @param c The character to test.
* @return True if the character is a lead surrogate code point.
*/
static inline bool Utf16IsLeadSurrogate(uint c)
{
return c >= 0xD800 && c <= 0xDBFF;
}
/**
* Is the given character a lead surrogate code point?
* @param c The character to test.
* @return True if the character is a lead surrogate code point.
*/
static inline bool Utf16IsTrailSurrogate(uint c)
{
return c >= 0xDC00 && c <= 0xDFFF;
}
/**
* Convert an UTF-16 surrogate pair to the corresponding Unicode character.
* @param lead Lead surrogate code point.
* @param trail Trail surrogate code point.
* @return Decoded Unicode character.
*/
static inline WChar Utf16DecodeSurrogate(uint lead, uint trail)
{
return 0x10000 + (((lead - 0xD800) << 10) | (trail - 0xDC00));
}
/**
* Decode an UTF-16 character.
* @param c Pointer to one or two UTF-16 code points.
* @return Decoded Unicode character.
*/
static inline WChar Utf16DecodeChar(const uint16 *c)
{
if (Utf16IsLeadSurrogate(c[0])) {
return Utf16DecodeSurrogate(c[0], c[1]);
} else {
return *c;
}
}
/**
* Is the given character a text direction character.
* @param c The character to test.
* @return true iff the character is used to influence
* the text direction.
*/
static inline bool IsTextDirectionChar(WChar c)
{
switch (c) {
case CHAR_TD_LRM:
case CHAR_TD_RLM:
case CHAR_TD_LRE:
case CHAR_TD_RLE:
case CHAR_TD_LRO:
case CHAR_TD_RLO:
case CHAR_TD_PDF:
return true;
default:
return false;
}
}
static inline bool IsPrintable(WChar c)
{
if (c < 0x20) return false;
if (c < 0xE000) return true;
if (c < 0xE200) return false;
return true;
}
/**
* Check whether UNICODE character is whitespace or not, i.e. whether
* this is a potential line-break character.
* @param c UNICODE character to check
* @return a boolean value whether 'c' is a whitespace character or not
* @see http://www.fileformat.info/info/unicode/category/Zs/list.htm
*/
static inline bool IsWhitespace(WChar c)
{
return c == 0x0020 /* SPACE */ || c == 0x3000; /* IDEOGRAPHIC SPACE */
}
/* Needed for NetBSD version (so feature) testing */
#if defined(__NetBSD__) || defined(__FreeBSD__)
#include <sys/param.h>
#endif
/* strcasestr is available for _GNU_SOURCE, BSD and some Apple */
#if defined(_GNU_SOURCE) || (defined(__BSD_VISIBLE) && __BSD_VISIBLE) || (defined(__APPLE__) && (!defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE))) || defined(_NETBSD_SOURCE)
# undef DEFINE_STRCASESTR
#else
# define DEFINE_STRCASESTR
char *strcasestr(const char *haystack, const char *needle);
#endif /* strcasestr is available */
int strnatcmp(const char *s1, const char *s2, bool ignore_garbage_at_front = false);
#endif /* STRING_FUNC_H */