thorvg/src/loaders/svg/tvgSvgUtil.cpp
2021-07-12 13:37:42 +09:00

325 lines
8.4 KiB
C++

/*
* Copyright (c) 2020-2021 Samsung Electronics Co., Ltd. All rights reserved.
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <math.h>
#include <memory.h>
#include <ctype.h>
#include <errno.h>
#include "tvgSvgUtil.h"
/************************************************************************/
/* Internal Class Implementation */
/************************************************************************/
static inline bool _floatExact(float a, float b)
{
return memcmp(&a, &b, sizeof (float)) == 0;
}
static uint8_t _hexCharToDec(const char c)
{
if (c >= 'a') return c - 'a' + 10;
else if (c >= 'A') return c - 'A' + 10;
else return c - '0';
}
static uint8_t _base64Value(const char chr)
{
if (chr >= 'A' && chr <= 'Z') return chr - 'A';
else if (chr >= 'a' && chr <= 'z') return chr - 'a' + ('Z' - 'A') + 1;
else if (chr >= '0' && chr <= '9') return chr - '0' + ('Z' - 'A') + ('z' - 'a') + 2;
else if (chr == '+' || chr == '-') return 62;
else return 63;
}
/************************************************************************/
/* External Class Implementation */
/************************************************************************/
/*
* https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/strtof-strtof-l-wcstof-wcstof-l?view=msvc-160
*
* src should be one of the following form :
*
* [whitespace] [sign] {digits [radix digits] | radix digits} [{e | E} [sign] digits]
* [whitespace] [sign] {INF | INFINITY}
* [whitespace] [sign] NAN [sequence]
*
* No hexadecimal form supported
* no sequence supported after NAN
*/
float svgUtilStrtof(const char *nPtr, char **endPtr)
{
const char *iter;
const char *a;
float val;
unsigned long long integerPart;
int minus;
if (endPtr) *endPtr = (char*)nPtr;
if (!nPtr) return 0.0f;
a = iter = nPtr;
//ignore leading whitespaces
while (isspace(*iter)) iter++;
//signed or not
minus = 1;
if (*iter == '-')
{
minus = -1;
iter++;
}
else if (*iter == '+') iter++;
if (tolower(*iter) == 'i')
{
if ((tolower(*(iter + 1)) == 'n') && (tolower(*(iter + 2)) == 'f'))
{
iter += 3;
}
else goto on_error;
if (tolower(*(iter + 3)) == 'i')
{
if ((tolower(*(iter + 4)) == 'n') &&
(tolower(*(iter + 5)) == 'i') &&
(tolower(*(iter + 6)) == 't') &&
(tolower(*(iter + 7)) == 'y'))
{
iter += 5;
}
else goto on_error;
}
if (endPtr) *endPtr = (char *)iter;
return (minus == -1) ? -INFINITY : INFINITY;
}
if (tolower(*iter) == 'n')
{
if ((tolower(*(iter + 1)) == 'a') && (tolower(*(iter + 2)) == 'n')) iter += 3;
else goto on_error;
if (endPtr) *endPtr = (char *)iter;
return (minus == -1) ? -NAN : NAN;
}
integerPart = 0;
//(optional) integer part before dot
if (isdigit(*iter))
{
for (; isdigit(*iter); iter++) integerPart = integerPart * 10ULL + (unsigned long long)(*iter - '0');
a = iter;
}
else if (*iter != '.')
{
val = 0.0;
goto on_success;
}
val = (float)integerPart;
//(optional) decimal part after dot
if (*iter == '.')
{
unsigned long long decimalPart;
unsigned long long pow10;
int count;
iter++;
decimalPart = 0;
count = 0;
pow10 = 1;
if (isdigit(*iter))
{
for (; isdigit(*iter); iter++, count++)
{
if (count < 19)
{
decimalPart = decimalPart * 10ULL + + (unsigned long long)(*iter - '0');
pow10 *= 10ULL;
}
}
}
val += (float)decimalPart / (float)pow10;
a = iter;
}
//(optional) exponent
if ((*iter == 'e') || (*iter == 'E'))
{
float scale = 1.0f;
unsigned int expo_part;
int minus_e;
++iter;
//Exception: svg may have 'em' unit for fonts. ex) 5em, 10.5em
if ((*iter == 'm') || (*iter == 'M')) {
//TODO: We don't support font em unit now, but has to multiply val * font size later...
a = iter + 1;
goto on_success;
}
//signed or not
minus_e = 1;
if (*iter == '-')
{
minus_e = -1;
++iter;
}
else if (*iter == '+') iter++;
//exponential part
expo_part = 0;
if (isdigit(*iter))
{
while (*iter == 0) iter++;
for (; isdigit(*iter); iter++)
{
expo_part = expo_part * 10U + (unsigned int)(*iter - '0');
}
}
else if (!isdigit(*(a - 1)))
{
a = nPtr;
goto on_success;
}
else if (*iter == 0) goto on_success;
if ((_floatExact(val, 2.2250738585072011)) && ((minus_e * (int)expo_part) == -308))
{
val *= 1.0e-308;
a = iter;
errno = ERANGE;
goto on_success;
}
if ((_floatExact(val, 2.2250738585072012)) && ((minus_e * (int)expo_part) <= -308))
{
val *= 1.0e-308;
a = iter;
goto on_success;
}
a = iter;
while (expo_part >= 8U)
{
scale *= 1E8;
expo_part -= 8U;
}
while (expo_part > 0U)
{
scale *= 10.0f;
expo_part--;
}
val = (minus_e == -1) ? (val / scale) : (val * scale);
}
else if ((iter > nPtr) && !isdigit(*(iter - 1)))
{
a = nPtr;
goto on_success;
}
on_success:
if (endPtr) *endPtr = (char *)a;
return minus * val;
on_error:
if (endPtr) *endPtr = (char *)nPtr;
return 0.0f;
}
string svgUtilURLDecode(const char *src)
{
if (!src) return nullptr;
auto length = strlen(src);
if (length == 0) return nullptr;
string decoded;
decoded.reserve(length);
char a, b;
while (*src) {
if (*src <= 0x20) {
++src;
continue;
}
if (*src == '%' &&
((a = src[1]) && (b = src[2])) &&
(isxdigit(a) && isxdigit(b))) {
decoded += (_hexCharToDec(a) << 4) + _hexCharToDec(b);
src+=3;
} else if (*src == '+') {
decoded += ' ';
src++;
} else {
decoded += *src++;
}
}
return decoded;
}
string svgUtilBase64Decode(const char *src)
{
if (!src) return nullptr;
auto length = strlen(src);
if (length == 0) return nullptr;
string decoded;
decoded.reserve(3*(1+(length >> 2)));
while (*src && *(src+1)) {
if (*src <= 0x20) {
++src;
continue;
}
auto value1 = _base64Value(src[0]);
auto value2 = _base64Value(src[1]);
decoded += (value1 << 2) + ((value2 & 0x30) >> 4);
if (!src[2] || src[2] == '=' || src[2] == '.') break;
auto value3 = _base64Value(src[2]);
decoded += ((value2 & 0x0f) << 4) + ((value3 & 0x3c) >> 2);
if (!src[3] || src[3] == '=' || src[3] == '.') break;
auto value4 = _base64Value(src[3]);
decoded += ((value3 & 0x03) << 6) + value4;
src += 4;
}
return decoded;
}