diff options
Diffstat (limited to 'src/mesa/drivers/dri/common')
-rw-r--r-- | src/mesa/drivers/dri/common/xmlconfig.c | 134 |
1 files changed, 132 insertions, 2 deletions
diff --git a/src/mesa/drivers/dri/common/xmlconfig.c b/src/mesa/drivers/dri/common/xmlconfig.c index 887f720f0d9..f45ab06ac41 100644 --- a/src/mesa/drivers/dri/common/xmlconfig.c +++ b/src/mesa/drivers/dri/common/xmlconfig.c @@ -137,6 +137,136 @@ static GLuint bsearchStr (const XML_Char *name, return count; } +/** \brief Locale-independent integer parser. + * + * Works similar to strtol. Leading space is NOT skipped. The input + * number may have an optional sign. Radix is specified by base. If + * base is 0 then decimal is assumed unless the input number is + * prefixed by 0x or 0X for hexadecimal or 0 for octal. After + * returning tail points to the first character that is not part of + * the integer number. If no number was found then tail points to the + * start of the input string. */ +static GLint strToI (const XML_Char *string, const XML_Char **tail, int base) { + GLint radix = base == 0 ? 10 : base; + GLint result = 0; + GLint sign = 1; + GLboolean numberFound = GL_FALSE; + const XML_Char *start = string; + + assert (radix >= 2 && radix <= 36); + + if (*string == '-') { + sign = -1; + string++; + } else if (*string == '+') + string++; + if (base == 0 && *string == '0') { + numberFound = GL_TRUE; + if (*(string+1) == 'x' || *(string+1) == 'X') { + radix = 16; + string += 2; + } else { + radix = 8; + string++; + } + } + do { + GLint digit = -1; + if (radix <= 10) { + if (*string >= '0' && *string < '0' + radix) + digit = *string - '0'; + } else { + if (*string >= '0' && *string <= '9') + digit = *string - '0'; + else if (*string >= 'a' && *string < 'a' + radix - 10) + digit = *string - 'a' + 10; + else if (*string >= 'A' && *string < 'A' + radix - 10) + digit = *string - 'A' + 10; + } + if (digit != -1) { + numberFound = GL_TRUE; + result = radix*result + digit; + string++; + } else + break; + } while (GL_TRUE); + *tail = numberFound ? string : start; + return sign * result; +} + +/** \brief Locale-independent floating-point parser. + * + * Works similar to strtod. Leading space is NOT skipped. The input + * number may have an optional sign. '.' is interpreted as decimal + * point and may occor at most once. Optionally the number may end in + * [eE]<exponent>, where <exponent> is an integer as recognized by + * strToI. In that case the result is number * 10^exponent. After + * returning tail points to the first character that is not part of + * the floating point number. If no number was found then tail points + * to the start of the input string. + * + * Uses two passes for maximum accuracy. */ +static GLfloat strToF (const XML_Char *string, const XML_Char **tail) { + GLint nDigits = 0, pointPos, exponent; + GLfloat sign = 1.0f, result = 0.0f, scale; + const XML_Char *start = string, *numStart; + + /* sign */ + if (*string == '-') { + sign = -1.0f; + string++; + } else if (*string == '+') + string++; + + /* first pass: determine position of decimal point, number of + * digits, exponent and the end of the number. */ + numStart = string; + while (*string >= '0' && *string <= '9') { + string++; + nDigits++; + } + pointPos = nDigits; + if (*string == '.') { + string++; + while (*string >= '0' && *string <= '9') { + string++; + nDigits++; + } + } + if (nDigits == 0) { + /* no digits, no number */ + *tail = start; + return 0.0f; + } + *tail = string; + if (*string == 'e' || *string == 'E') { + const XML_Char *expTail; + exponent = strToI (string+1, &expTail, 10); + if (expTail == string+1) + exponent = 0; + else + *tail = expTail; + } else + exponent = 0; + string = numStart; + + /* scale of the first digit */ + scale = sign * powf (10.0f, (GLfloat)(pointPos-1 + exponent)); + + /* second pass: parse digits */ + do { + if (*string != '.') { + assert (*string >= '0' && *string <= '9'); + result += scale * (GLfloat)(*string - '0'); + scale *= 0.1f; + nDigits--; + } + string++; + } while (nDigits > 0); + + return result; +} + /** \brief Parse a value of a given type. */ static GLboolean parseValue (driOptionValue *v, driOptionType type, const XML_Char *string) { @@ -157,10 +287,10 @@ static GLboolean parseValue (driOptionValue *v, driOptionType type, break; case DRI_ENUM: /* enum is just a special integer */ case DRI_INT: - v->_int = strtol (string, (char **)&tail, 0); + v->_int = strToI (string, &tail, 0); break; case DRI_FLOAT: - v->_float = strtod (string, (char **)&tail); + v->_float = strToF (string, &tail); break; } |