# string.cpp

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    00001 /* $Id: string.cpp 19155 2010-02-17 21:29:31Z rubidium $ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * 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.
    00006  * 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.
    00007  * 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/>.
    00008  */
    00009
    00012 #include "stdafx.h"
    00013 #include "debug.h"
    00014 #include "core/alloc_func.hpp"
    00015 #include "core/math_func.hpp"
    00016 #include "string_func.h"
    00017
    00018 #include "table/control_codes.h"
    00019
    00020 #include <stdarg.h>
    00021 #include <ctype.h> /* required for tolower() */
    00022
    00023 #ifdef _MSC_VER
    00024 #include <errno.h> // required by vsnprintf implementation for MSVC
    00025 #endif
    00026
    00037 static int CDECL vseprintf(char *str, const char *last, const char *format, va_list ap)
    00038 {
    00039   ptrdiff_t diff = last - str;
    00040   if (diff < 0) return 0;
    00041   return min((int)diff, vsnprintf(str, diff + 1, format, ap));
    00042 }
    00043
    00044 void ttd_strlcat(char *dst, const char *src, size_t size)
    00045 {
    00046   assert(size > 0);
    00047   while (size > 0 && *dst != '\0') {
    00048     size--;
    00049     dst++;
    00050   }
    00051
    00052   ttd_strlcpy(dst, src, size);
    00053 }
    00054
    00055
    00056 void ttd_strlcpy(char *dst, const char *src, size_t size)
    00057 {
    00058   assert(size > 0);
    00059   while (--size > 0 && *src != '\0') {
    00060     *dst++ = *src++;
    00061   }
    00062   *dst = '\0';
    00063 }
    00064
    00065
    00066 char *strecat(char *dst, const char *src, const char *last)
    00067 {
    00068   assert(dst <= last);
    00069   while (*dst != '\0') {
    00070     if (dst == last) return dst;
    00071     dst++;
    00072   }
    00073
    00074   return strecpy(dst, src, last);
    00075 }
    00076
    00077
    00078 char *strecpy(char *dst, const char *src, const char *last)
    00079 {
    00080   assert(dst <= last);
    00081   while (dst != last && *src != '\0') {
    00082     *dst++ = *src++;
    00083   }
    00084   *dst = '\0';
    00085
    00086   if (dst == last && *src != '\0') {
    00087 #ifdef STRGEN
    00088     error("String too long for destination buffer");
    00089 #else /* STRGEN */
    00090     DEBUG(misc, 0, "String too long for destination buffer");
    00091 #endif /* STRGEN */
    00092   }
    00093   return dst;
    00094 }
    00095
    00096
    00097 char *CDECL str_fmt(const char *str, ...)
    00098 {
    00099   char buf[4096];
    00100   va_list va;
    00101
    00102   va_start(va, str);
    00103   int len = vseprintf(buf, lastof(buf), str, va);
    00104   va_end(va);
    00105   char *p = MallocT<char>(len + 1);
    00106   memcpy(p, buf, len + 1);
    00107   return p;
    00108 }
    00109
    00110
    00111 void str_validate(char *str, const char *last, bool allow_newlines, bool ignore)
    00112 {
    00113   /* Assume the ABSOLUTE WORST to be in str as it comes from the outside. */
    00114
    00115   char *dst = str;
    00116   while (*str != '\0') {
    00117     size_t len = Utf8EncodedCharLen(*str);
    00118     /* If the character is unknown, i.e. encoded length is 0
    00119      * we assume worst case for the length check.
    00120      * The length check is needed to prevent Utf8Decode to read
    00121      * over the terminating '\0' if that happens to be placed
    00122      * within the encoding of an UTF8 character. */
    00123     if ((len == 0 && str + 4 > last) || str + len > last) break;
    00124
    00125     WChar c;
    00126     len = Utf8Decode(&c, str);
    00127     /* It's possible to encode the string termination character
    00128      * into a multiple bytes. This prevents those termination
    00129      * characters to be skipped */
    00130     if (c == '\0') break;
    00131
    00132     if (IsPrintable(c) && (c < SCC_SPRITE_START || c > SCC_SPRITE_END)) {
    00133       /* Copy the character back. Even if dst is current the same as str
    00134        * (i.e. no characters have been changed) this is quicker than
    00135        * moving the pointers ahead by len */
    00136       do {
    00137         *dst++ = *str++;
    00138       } while (--len != 0);
    00139     } else if (allow_newlines && c == '\n') {
    00140       *dst++ = *str++;
    00141     } else {
    00142       if (allow_newlines && c == '\r' && str[1] == '\n') {
    00143         str += len;
    00144         continue;
    00145       }
    00146       /* Replace the undesirable character with a question mark */
    00147       str += len;
    00148       if (!ignore) *dst++ = '?';
    00149     }
    00150   }
    00151
    00152   *dst = '\0';
    00153 }
    00154
    00155
    00156 void str_strip_colours(char *str)
    00157 {
    00158   char *dst = str;
    00159   WChar c;
    00160   size_t len;
    00161
    00162   for (len = Utf8Decode(&c, str); c != '\0'; len = Utf8Decode(&c, str)) {
    00163     if (c < SCC_BLUE || c > SCC_BLACK) {
    00164       /* Copy the character back. Even if dst is current the same as str
    00165        * (i.e. no characters have been changed) this is quicker than
    00166        * moving the pointers ahead by len */
    00167       do {
    00168         *dst++ = *str++;
    00169       } while (--len != 0);
    00170     } else {
    00171       /* Just skip (strip) the colour codes */
    00172       str += len;
    00173     }
    00174   }
    00175   *dst = '\0';
    00176 }
    00177
    00186 void strtolower(char *str)
    00187 {
    00188   for (; *str != '\0'; str++) *str = tolower(*str);
    00189 }
    00190
    00198 bool IsValidChar(WChar key, CharSetFilter afilter)
    00199 {
    00200   switch (afilter) {
    00201     case CS_ALPHANUMERAL:  return IsPrintable(key);
    00202     case CS_NUMERAL:       return (key >= '0' && key <= '9');
    00203     case CS_NUMERAL_SPACE: return (key >= '0' && key <= '9') || key == ' ';
    00204     case CS_ALPHA:         return IsPrintable(key) && !(key >= '0' && key <= '9');
    00205   }
    00206
    00207   return false;
    00208 }
    00209
    00210 #ifdef WIN32
    00211 /* Since version 3.14, MinGW Runtime has snprintf() and vsnprintf() conform to C99 but it's not the case for older versions */
    00212 #if (__MINGW32_MAJOR_VERSION < 3) || ((__MINGW32_MAJOR_VERSION == 3) && (__MINGW32_MINOR_VERSION < 14))
    00213 int CDECL snprintf(char *str, size_t size, const char *format, ...)
    00214 {
    00215   va_list ap;
    00216   int ret;
    00217
    00218   va_start(ap, format);
    00219   ret = vsnprintf(str, size, format, ap);
    00220   va_end(ap);
    00221   return ret;
    00222 }
    00223 #endif /* MinGW Runtime < 3.14 */
    00224
    00225 #ifdef _MSC_VER
    00226
    00233 int CDECL vsnprintf(char *str, size_t size, const char *format, va_list ap)
    00234 {
    00235   if (size == 0) return 0;
    00236
    00237   errno = 0;
    00238   int ret = _vsnprintf(str, size, format, ap);
    00239
    00240   if (ret < 0) {
    00241     if (errno != ERANGE) {
    00242       /* There's a formatting error, better get that looked
    00243        * at properly instead of ignoring it. */
    00244       NOT_REACHED();
    00245     }
    00246   } else if ((size_t)ret < size) {
    00247     /* The buffer is big enough for the number of
    00248      * characers stored (excluding null), i.e.
    00249      * the string has been null-terminated. */
    00250     return ret;
    00251   }
    00252
    00253   /* The buffer is too small for _vsnprintf to write the
    00254    * null-terminator at its end and return size. */
    00255   str[size - 1] = '\0';
    00256   return size;
    00257 }
    00258 #endif /* _MSC_VER */
    00259
    00260 #endif /* WIN32 */
    00261
    00271 int CDECL seprintf(char *str, const char *last, const char *format, ...)
    00272 {
    00273   va_list ap;
    00274
    00275   va_start(ap, format);
    00276   int ret = vseprintf(str, last, format, ap);
    00277   va_end(ap);
    00278   return ret;
    00279 }
    00280
    00281
    00287 char *md5sumToString(char *buf, const char *last, const uint8 md5sum[16])
    00288 {
    00289   char *p = buf;
    00290
    00291   for (uint i = 0; i < 16; i++) {
    00292     p += seprintf(p, last, "%02X", md5sum[i]);
    00293   }
    00294
    00295   return p;
    00296 }
    00297
    00298
    00299 /* UTF-8 handling routines */
    00300
    00301
    00302 /* Decode and consume the next UTF-8 encoded character
    00303  * @param c Buffer to place decoded character.
    00304  * @param s Character stream to retrieve character from.
    00305  * @return Number of characters in the sequence.
    00306  */
    00307 size_t Utf8Decode(WChar *c, const char *s)
    00308 {
    00309   assert(c != NULL);
    00310
    00311   if (!HasBit(s[0], 7)) {
    00312     /* Single byte character: 0xxxxxxx */
    00313     *c = s[0];
    00314     return 1;
    00315   } else if (GB(s[0], 5, 3) == 6) {
    00316     if (IsUtf8Part(s[1])) {
    00317       /* Double byte character: 110xxxxx 10xxxxxx */
    00318       *c = GB(s[0], 0, 5) << 6 | GB(s[1], 0, 6);
    00319       if (*c >= 0x80) return 2;
    00320     }
    00321   } else if (GB(s[0], 4, 4) == 14) {
    00322     if (IsUtf8Part(s[1]) && IsUtf8Part(s[2])) {
    00323       /* Triple byte character: 1110xxxx 10xxxxxx 10xxxxxx */
    00324       *c = GB(s[0], 0, 4) << 12 | GB(s[1], 0, 6) << 6 | GB(s[2], 0, 6);
    00325       if (*c >= 0x800) return 3;
    00326     }
    00327   } else if (GB(s[0], 3, 5) == 30) {
    00328     if (IsUtf8Part(s[1]) && IsUtf8Part(s[2]) && IsUtf8Part(s[3])) {
    00329       /* 4 byte character: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */
    00330       *c = GB(s[0], 0, 3) << 18 | GB(s[1], 0, 6) << 12 | GB(s[2], 0, 6) << 6 | GB(s[3], 0, 6);
    00331       if (*c >= 0x10000 && *c <= 0x10FFFF) return 4;
    00332     }
    00333   }
    00334
    00335   /* DEBUG(misc, 1, "[utf8] invalid UTF-8 sequence"); */
    00336   *c = '?';
    00337   return 1;
    00338 }
    00339
    00340
    00341 /* Encode a unicode character and place it in the buffer
    00342  * @param buf Buffer to place character.
    00343  * @param c   Unicode character to encode.
    00344  * @return Number of characters in the encoded sequence.
    00345  */
    00346 size_t Utf8Encode(char *buf, WChar c)
    00347 {
    00348   if (c < 0x80) {
    00349     *buf = c;
    00350     return 1;
    00351   } else if (c < 0x800) {
    00352     *buf++ = 0xC0 + GB(c,  6, 5);
    00353     *buf   = 0x80 + GB(c,  0, 6);
    00354     return 2;
    00355   } else if (c < 0x10000) {
    00356     *buf++ = 0xE0 + GB(c, 12, 4);
    00357     *buf++ = 0x80 + GB(c,  6, 6);
    00358     *buf   = 0x80 + GB(c,  0, 6);
    00359     return 3;
    00360   } else if (c < 0x110000) {
    00361     *buf++ = 0xF0 + GB(c, 18, 3);
    00362     *buf++ = 0x80 + GB(c, 12, 6);
    00363     *buf++ = 0x80 + GB(c,  6, 6);
    00364     *buf   = 0x80 + GB(c,  0, 6);
    00365     return 4;
    00366   }
    00367
    00368   /* DEBUG(misc, 1, "[utf8] can't UTF-8 encode value 0x%X", c); */
    00369   *buf = '?';
    00370   return 1;
    00371 }
    00372
    00380 size_t Utf8TrimString(char *s, size_t maxlen)
    00381 {
    00382   size_t length = 0;
    00383
    00384   for (const char *ptr = strchr(s, '\0'); *s != '\0';) {
    00385     size_t len = Utf8EncodedCharLen(*s);
    00386     /* Silently ignore invalid UTF8 sequences, our only concern trimming */
    00387     if (len == 0) len = 1;
    00388
    00389     /* Take care when a hard cutoff was made for the string and
    00390      * the last UTF8 sequence is invalid */
    00391     if (length + len >= maxlen || (s + len > ptr)) break;
    00392     s += len;
    00393     length += len;
    00394   }
    00395
    00396   *s = '\0';
    00397   return length;
    00398 }
    00399
    00400 #ifndef _GNU_SOURCE
    00401 #include "core/math_func.hpp"
    00402 char *strndup(const char *s, size_t len)
    00403 {
    00404   len = min(strlen(s), len);
    00405   char *tmp = CallocT<char>(len + 1);
    00406   memcpy(tmp, s, len);
    00407   return tmp;
    00408 }
    00409 #endif /* !_GNU_SOURCE */
    00410
    00411 #ifdef DEFINE_STRCASESTR
    00412 char *strcasestr(const char *haystack, const char *needle)
    00413 {
    00414   size_t hay_len = strlen(haystack);
    00415   size_t needle_len = strlen(needle);
    00416   while (hay_len >= needle_len) {
    00417     if (strncasecmp(haystack, needle, needle_len) == 0) return const_cast<char *>(haystack);
    00418
    00419     haystack++;
    00420     hay_len--;
    00421   }
    00422
    00423   return NULL;
    00424 }
    00425 #endif /* DEFINE_STRCASESTR */