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Diffstat (limited to 'src/mongo/base/parse_number.cpp')
| -rw-r--r-- | src/mongo/base/parse_number.cpp | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/src/mongo/base/parse_number.cpp b/src/mongo/base/parse_number.cpp new file mode 100644 index 00000000000..ed3d0a89cd5 --- /dev/null +++ b/src/mongo/base/parse_number.cpp @@ -0,0 +1,117 @@ +/* Copyright 2012 10gen Inc. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "mongo/base/parse_number.h" + +#include <cerrno> +#include <cstdlib> +#include <cstring> +#include <limits> + +#include "mongo/platform/strtoll.h" + +/** + * Macro providing the specialized implementation of parseNumberFromStringWithBase<NUMBER_TYPE> + * in terms of the strtol-like function CONV_FUNC. + */ +#define DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE(NUMBER_TYPE, CONV_FUNC) \ + template<> \ + Status parseNumberFromStringWithBase<NUMBER_TYPE>( \ + const char* stringValue, \ + int base, \ + NUMBER_TYPE* out) { \ + \ + typedef ::std::numeric_limits<NUMBER_TYPE> limits; \ + \ + if (base == 1 || base < 0 || base > 36) \ + return Status(ErrorCodes::BadValue, "Invalid base", 0); \ + \ + if (stringValue[0] == '\0' || ::isspace(stringValue[0])) \ + return Status(ErrorCodes::FailedToParse, "Unparseable string", 0); \ + \ + if (!limits::is_signed && (stringValue[0] == '-')) \ + return Status(ErrorCodes::FailedToParse, "Negative value", 0); \ + \ + errno = 0; \ + char* endPtr; \ + NUMBER_TYPE result = CONV_FUNC(stringValue, &endPtr, base); \ + if (*endPtr != '\0') \ + return Status(ErrorCodes::FailedToParse, "Non-digit characters at end of string");\ + \ + if ((ERANGE == errno) && ((result == limits::max()) || (result == limits::min()))) \ + return Status(ErrorCodes::FailedToParse, "Value out of range", 0); \ + \ + if (errno != 0 && result == 0) \ + return Status(ErrorCodes::FailedToParse, "Unparseable string", 0); \ + \ + *out = result; \ + return Status::OK(); \ + } + +/** + * Macro providing the specialized implementation of parseNumberFromStringWithBase<NUMBER_TYPE> + * in terms of parseNumberFromStringWithBase<BIGGER_NUMBER_TYPE>. + */ +#define DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE_IN_TERMS_OF(NUMBER_TYPE, BIGGER_NUMBER_TYPE) \ + template<> \ + Status parseNumberFromStringWithBase<NUMBER_TYPE>( \ + const char* stringValue, \ + int base, \ + NUMBER_TYPE* out) { \ + \ + return parseNumberFromStringWithBaseUsingBiggerNumberType<NUMBER_TYPE, \ + BIGGER_NUMBER_TYPE>( \ + stringValue, base, out); \ + } + +namespace mongo { + +namespace { + + /** + * This function implements the functionality of parseNumberFromStringWithBase<NumberType> + * by calling parseNumberFromStringWithBase<BiggerNumberType> and checking for overflow on + * the range of NumberType. Used for "int" and "short" types, for which an equivalent to + * strtol is unavailable. + */ + template<typename NumberType, typename BiggerNumberType> + Status parseNumberFromStringWithBaseUsingBiggerNumberType( + const char* stringValue, + int base, + NumberType* out) { + typedef ::std::numeric_limits<NumberType> limits; + BiggerNumberType result; + Status status = parseNumberFromStringWithBase(stringValue, base, &result); + if (Status::OK() != status) + return status; + if ((result < limits::min()) || (result > limits::max())) + return Status(ErrorCodes::FailedToParse, "Value out of range", 0); + *out = static_cast<NumberType>(result); + return Status::OK(); + } +} // namespace + + // Definition of the various supported implementations of parseNumberFromStringWithBase. + + DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE(long, strtol) + DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE(long long, strtoll) + DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE(unsigned long, strtoul) + DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE(unsigned long long, strtoull) + + DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE_IN_TERMS_OF(short, long) + DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE_IN_TERMS_OF(unsigned short, unsigned long) + DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE_IN_TERMS_OF(int, long) + DEFINE_PARSE_NUMBER_FROM_STRING_WITH_BASE_IN_TERMS_OF(unsigned int, unsigned long) +} // namespace mongo |