string to int: Allow specifying string size

CMakeLists.txt

@@ -121,8 +121,8 @@ set(META_APP_AUTHOR "Martchus")
 set(META_APP_URL "https://github.com/${META_APP_AUTHOR}/${META_PROJECT_NAME}")
 set(META_APP_DESCRIPTION "Common C++ classes and routines used by my applications such as argument parser, IO and conversion utilities")
 set(META_VERSION_MAJOR 4)
-set(META_VERSION_MINOR 8)
-set(META_VERSION_PATCH 1)
+set(META_VERSION_MINOR 9)
+set(META_VERSION_PATCH 0)
 
 # find required 3rd party libraries
 include(3rdParty)

conversion/stringconversion.h

@@ -301,7 +301,7 @@ StringType numberToString(IntegralType number, typename StringType::value_type b
  * \tparam StringType The string type (should be an instantiation of the basic_string class template).
  * \remarks This function is using std::basic_stringstream interanlly and hence also has its limitations (eg. regarding
  *          \a base and types).
- * \sa stringToNumber()
+ * \sa stringToNumber(), bufferToNumber()
  */
 template <typename FloatingType, class StringType = std::string, Traits::EnableIf<std::is_floating_point<FloatingType>>...>
 StringType numberToString(FloatingType number, typename StringType::value_type base = 10)
@@ -334,11 +334,11 @@ template <typename CharType> CharType charToDigit(CharType character, CharType b
 }
 
 /*!
- * \brief Converts the given \a string to a number assuming \a string uses the specified \a base.
+ * \brief Converts the given \a string to an unsigned number assuming \a string uses the specified \a base.
  * \tparam NumberType The data type used to store the converted value.
  * \tparam StringType The string type (should be an instantiation of the basic_string class template).
  * \throws A ConversionException will be thrown if the provided \a string is not a valid number.
- * \sa numberToString()
+ * \sa numberToString(), bufferToNumber()
  */
 template <typename IntegralType, class StringType, Traits::EnableIf<std::is_integral<IntegralType>, Traits::Not<std::is_signed<IntegralType>>>...>
 IntegralType stringToNumber(const StringType &string, typename StringType::value_type base = 10)
@@ -355,11 +355,11 @@ IntegralType stringToNumber(const StringType &string, typename StringType::value
 }
 
 /*!
- * \brief Converts the given \a string to a number assuming \a string uses the specified \a base.
+ * \brief Converts the given \a string to a signed number assuming \a string uses the specified \a base.
  * \tparam NumberType The data type used to store the converted value.
  * \tparam StringType The string type (should be an instantiation of the basic_string class template).
  * \throws A ConversionException will be thrown if the provided \a string is not a valid number.
- * \sa numberToString()
+ * \sa numberToString(), bufferToNumber()
  */
 template <typename IntegralType, class StringType, Traits::EnableIf<std::is_integral<IntegralType>, std::is_signed<IntegralType>>...>
 IntegralType stringToNumber(const StringType &string, typename StringType::value_type base = 10)
@@ -393,7 +393,7 @@ IntegralType stringToNumber(const StringType &string, typename StringType::value
  * \throws A ConversionException will be thrown if the provided \a string is not a valid number.
  * \remarks This function is using std::basic_stringstream interanlly and hence also has its limitations (eg. regarding
  *          \a base and types).
- * \sa numberToString()
+ * \sa numberToString(), bufferToNumber()
  */
 template <typename FloatingType, class StringType, Traits::EnableIf<std::is_floating_point<FloatingType>>...>
 FloatingType stringToNumber(const StringType &string, typename StringType::value_type base = 10)
@@ -409,11 +409,11 @@ FloatingType stringToNumber(const StringType &string, typename StringType::value
 }
 
 /*!
- * \brief Converts the given null-terminated \a string to a numeric value using the specified \a base.
+ * \brief Converts the given null-terminated \a string to an unsigned numeric value using the specified \a base.
  * \tparam NumberType The data type used to store the converted value.
  * \tparam StringType The string type (should be an instantiation of the basic_string class template).
  * \throws A ConversionException will be thrown if the provided \a string is not a valid number.
- * \sa numberToString()
+ * \sa numberToString(), bufferToNumber()
  */
 template <typename IntegralType, class CharType, Traits::EnableIf<std::is_integral<IntegralType>, Traits::Not<std::is_signed<IntegralType>>>...>
 IntegralType stringToNumber(const CharType *string, unsigned char base = 10)
@@ -430,11 +430,32 @@ IntegralType stringToNumber(const CharType *string, unsigned char base = 10)
 }
 
 /*!
- * \brief Converts the given null-terminated \a string to a numeric value using the specified \a base.
+ * \brief Converts the given \a string of \a size characters to an unsigned numeric value using the specified \a base.
  * \tparam NumberType The data type used to store the converted value.
  * \tparam StringType The string type (should be an instantiation of the basic_string class template).
  * \throws A ConversionException will be thrown if the provided \a string is not a valid number.
- * \sa numberToString()
+ * \sa numberToString(), stringToNumber()
+ */
+template <typename IntegralType, class CharType, Traits::EnableIf<std::is_integral<IntegralType>, Traits::Not<std::is_signed<IntegralType>>>...>
+IntegralType bufferToNumber(const CharType *string, std::size_t size, unsigned char base = 10)
+{
+    IntegralType result = 0;
+    for (const CharType *end = string + size; string != end; ++string) {
+        if (*string == ' ') {
+            continue;
+        }
+        result *= base;
+        result += charToDigit<CharType>(*string, base);
+    }
+    return result;
+}
+
+/*!
+ * \brief Converts the given null-terminated \a string to a signed numeric value using the specified \a base.
+ * \tparam NumberType The data type used to store the converted value.
+ * \tparam StringType The string type (should be an instantiation of the basic_string class template).
+ * \throws A ConversionException will be thrown if the provided \a string is not a valid number.
+ * \sa numberToString(), bufferToNumber()
  */
 template <typename IntegralType, class CharType, Traits::EnableIf<std::is_integral<IntegralType>, std::is_signed<IntegralType>>...>
 IntegralType stringToNumber(const CharType *string, unsigned char base = 10)
@@ -462,6 +483,40 @@ IntegralType stringToNumber(const CharType *string, unsigned char base = 10)
     return negative ? -result : result;
 }
 
+/*!
+ * \brief Converts the given \a string of \a size characters to a signed numeric value using the specified \a base.
+ * \tparam NumberType The data type used to store the converted value.
+ * \tparam StringType The string type (should be an instantiation of the basic_string class template).
+ * \throws A ConversionException will be thrown if the provided \a string is not a valid number.
+ * \sa numberToString(), stringToNumber()
+ */
+template <typename IntegralType, class CharType, Traits::EnableIf<std::is_integral<IntegralType>, std::is_signed<IntegralType>>...>
+IntegralType bufferToNumber(const CharType *string, std::size_t size, unsigned char base = 10)
+{
+    if (!size) {
+        return 0;
+    }
+    const CharType *end = string + size;
+    for (; string != end && *string == ' '; ++string)
+        ;
+    if (string == end) {
+        return 0;
+    }
+    const bool negative = (*string == '-');
+    if (negative) {
+        ++string;
+    }
+    IntegralType result = 0;
+    for (; string != end; ++string) {
+        if (*string == ' ') {
+            continue;
+        }
+        result *= base;
+        result += charToDigit<CharType>(*string, base);
+    }
+    return negative ? -result : result;
+}
+
 /*!
  * \brief Interprets the given \a integer at the specified position as std::string using the specified byte order.
  *

tests/conversiontests.cpp

@@ -228,24 +228,27 @@ void ConversionTests::testStringEncodingConversions()
 void ConversionTests::testStringConversions()
 {
     // stringToNumber() / numberToString() with zero and random numbers
-    CPPUNIT_ASSERT_EQUAL(string("0"), numberToString<unsigned int>(0));
-    CPPUNIT_ASSERT_EQUAL(string("0"), numberToString<signed int>(0));
+    CPPUNIT_ASSERT_EQUAL("0"s, numberToString<unsigned int>(0));
+    CPPUNIT_ASSERT_EQUAL("0"s, numberToString<signed int>(0));
     uniform_int_distribution<int64> randomDistSigned(numeric_limits<int64>::min());
     uniform_int_distribution<uint64> randomDistUnsigned(0);
+    const string stringMsg("string"), wideStringMsg("wide string"), bufferMsg("buffer");
     for (byte b = 1; b < 100; ++b) {
         auto signedRandom = randomDistSigned(m_randomEngine);
         auto unsignedRandom = randomDistUnsigned(m_randomEngine);
         for (const auto base : initializer_list<byte>{ 2, 8, 10, 16 }) {
-            auto resultString = stringToNumber<uint64, string>(numberToString<uint64, string>(unsignedRandom, base), base);
-            auto resultWideString = stringToNumber<uint64, wstring>(numberToString<uint64, wstring>(unsignedRandom, base), base);
-            CPPUNIT_ASSERT_EQUAL(unsignedRandom, resultString);
-            CPPUNIT_ASSERT_EQUAL(unsignedRandom, resultWideString);
+            const auto asString = numberToString<uint64, string>(unsignedRandom, static_cast<string::value_type>(base));
+            const auto asWideString = numberToString<uint64, wstring>(unsignedRandom, base);
+            CPPUNIT_ASSERT_EQUAL_MESSAGE(stringMsg, unsignedRandom, stringToNumber<uint64>(asString, static_cast<string::value_type>(base)));
+            CPPUNIT_ASSERT_EQUAL_MESSAGE(wideStringMsg, unsignedRandom, stringToNumber<uint64>(asWideString, base));
+            CPPUNIT_ASSERT_EQUAL_MESSAGE(bufferMsg, unsignedRandom, bufferToNumber<uint64>(asString.data(), asString.size(), base));
         }
         for (const auto base : initializer_list<byte>{ 10 }) {
-            auto resultString = stringToNumber<int64, string>(numberToString<int64, string>(signedRandom, base), base);
-            auto resultWideString = stringToNumber<int64, wstring>(numberToString<int64, wstring>(signedRandom, base), base);
-            CPPUNIT_ASSERT_EQUAL(signedRandom, resultString);
-            CPPUNIT_ASSERT_EQUAL(signedRandom, resultWideString);
+            const auto asString = numberToString<int64, string>(signedRandom, static_cast<string::value_type>(base));
+            const auto asWideString = numberToString<int64, wstring>(signedRandom, base);
+            CPPUNIT_ASSERT_EQUAL_MESSAGE(stringMsg, signedRandom, stringToNumber<int64>(asString, static_cast<string::value_type>(base)));
+            CPPUNIT_ASSERT_EQUAL_MESSAGE(wideStringMsg, signedRandom, stringToNumber<int64>(asWideString, base));
+            CPPUNIT_ASSERT_EQUAL_MESSAGE(bufferMsg, signedRandom, bufferToNumber<int64>(asString.data(), asString.size(), base));
         }
     }
 
@@ -254,10 +257,12 @@ void ConversionTests::testStringConversions()
     CPPUNIT_ASSERT_EQUAL(1, stringToNumber<int32>(L"01"s));
     CPPUNIT_ASSERT_EQUAL(1, stringToNumber<int32>(u"01"s));
     CPPUNIT_ASSERT_EQUAL(-23, stringToNumber<int32>(" - 023"s));
+    CPPUNIT_ASSERT_EQUAL(-23, bufferToNumber<int32>(" - 023", 6));
     CPPUNIT_ASSERT_EQUAL(1u, stringToNumber<uint32>("01"));
     CPPUNIT_ASSERT_EQUAL(1u, stringToNumber<uint32>(L"01"s));
     CPPUNIT_ASSERT_EQUAL(1u, stringToNumber<uint32>(u"01"s));
     CPPUNIT_ASSERT_EQUAL(23u, stringToNumber<uint32>("  023"s));
+    CPPUNIT_ASSERT_EQUAL(23u, bufferToNumber<uint32>("  023", 5));
 
     // interpretIntegerAsString()
     CPPUNIT_ASSERT_EQUAL("TEST"s, interpretIntegerAsString<uint32>(0x54455354));