Fix various MSVC warnings

Based on VC2017 output

5 files changed, 46 insertions, 34 deletions

diff --git a/src/lib/utils/ct_utils.h b/src/lib/utils/ct_utils.h
index 68bd01c94..709b6d9e5 100644
--- a/src/lib/utils/ct_utils.h
+++ b/src/lib/utils/ct_utils.h
@@ -115,7 +115,7 @@ inline T is_zero(T x)
 template<typename T>
 inline T is_equal(T x, T y)
    {
-   return is_zero(x ^ y);
+   return is_zero<T>(x ^ y);
    }
 
 template<typename T>
diff --git a/src/lib/utils/data_src.cpp b/src/lib/utils/data_src.cpp
index 0e9fd0e33..078d3f2ea 100644
--- a/src/lib/utils/data_src.cpp
+++ b/src/lib/utils/data_src.cpp
@@ -110,7 +110,7 @@ size_t DataSource_Stream::read(uint8_t out[], size_t length)
    if(m_source.bad())
       throw Stream_IO_Error("DataSource_Stream::read: Source failure");
 
-   size_t got = m_source.gcount();
+   const size_t got = static_cast<size_t>(m_source.gcount());
    m_total_read += got;
    return got;
    }
@@ -119,7 +119,7 @@ bool DataSource_Stream::check_available(size_t n)
    {
    const std::streampos orig_pos = m_source.tellg();
    m_source.seekg(0, std::ios::end);
-   const size_t avail = m_source.tellg() - orig_pos;
+   const size_t avail = static_cast<size_t>(m_source.tellg() - orig_pos);
    m_source.seekg(orig_pos);
    return (avail >= n);
    }
@@ -140,7 +140,7 @@ size_t DataSource_Stream::peek(uint8_t out[], size_t length, size_t offset) cons
       m_source.read(reinterpret_cast<char*>(buf.data()), buf.size());
       if(m_source.bad())
          throw Stream_IO_Error("DataSource_Stream::peek: Source failure");
-      got = m_source.gcount();
+      got = static_cast<size_t>(m_source.gcount());
       }
 
    if(got == offset)
@@ -148,7 +148,7 @@ size_t DataSource_Stream::peek(uint8_t out[], size_t length, size_t offset) cons
       m_source.read(reinterpret_cast<char*>(out), length);
       if(m_source.bad())
          throw Stream_IO_Error("DataSource_Stream::peek: Source failure");
-      got = m_source.gcount();
+      got = static_cast<size_t>(m_source.gcount());
       }
 
    if(m_source.eof())
diff --git a/src/lib/utils/os_utils.cpp b/src/lib/utils/os_utils.cpp
index 7bd9b842d..e887d6e76 100644
--- a/src/lib/utils/os_utils.cpp
+++ b/src/lib/utils/os_utils.cpp
@@ -51,12 +51,13 @@ uint64_t OS::get_processor_timestamp()
 #elif defined(BOTAN_USE_GCC_INLINE_ASM)
 
 #if defined(BOTAN_TARGET_CPU_IS_X86_FAMILY)
-   if(CPUID::has_rdtsc()) // not available on all x86 CPUs
-      {
-      uint32_t rtc_low = 0, rtc_high = 0;
-      asm volatile("rdtsc" : "=d" (rtc_high), "=a" (rtc_low));
-      return (static_cast<uint64_t>(rtc_high) << 32) | rtc_low;
-      }
+
+   if(CPUID::has_rdtsc() == false)
+      return 0;
+
+   uint32_t rtc_low = 0, rtc_high = 0;
+   asm volatile("rdtsc" : "=d" (rtc_high), "=a" (rtc_low));
+   return (static_cast<uint64_t>(rtc_high) << 32) | rtc_low;
 
 #elif defined(BOTAN_TARGET_ARCH_IS_PPC64)
    uint32_t rtc_low = 0, rtc_high = 0;
@@ -99,11 +100,12 @@ uint64_t OS::get_processor_timestamp()
 
 #else
    //#warning "OS::get_processor_timestamp not implemented"
+   return 0;
 #endif
 
-#endif
-
+#else
    return 0;
+#endif
    }
 
 uint64_t OS::get_high_resolution_clock()
diff --git a/src/lib/utils/parsing.cpp b/src/lib/utils/parsing.cpp
index 7583767f0..e0173443f 100644
--- a/src/lib/utils/parsing.cpp
+++ b/src/lib/utils/parsing.cpp
@@ -17,37 +17,40 @@
 
 namespace Botan {
 
+uint16_t to_uint16(const std::string& str)
+   {
+   const uint32_t x = to_u32bit(str);
+
+   if(x >> 16)
+      throw Invalid_Argument("Integer value exceeds 16 bit range");
+
+   return static_cast<uint16_t>(x);
+   }
+
 uint32_t to_u32bit(const std::string& str)
    {
-   try
+   // std::stoul is not strict enough. Ensure that str is digit only [0-9]*
+   for(const char chr : str)
       {
-      // std::stoul is not strict enough. Ensure that str is digit only [0-9]*
-      for (const char chr : str)
+      if(chr < '0' || chr > '9')
          {
-         if (chr < '0' || chr > '9')
-            {
-            auto chrAsString = std::string(1, chr);
-            throw Invalid_Argument("String contains non-digit char: " + chrAsString);
-            }
+         std::string chrAsString(1, chr);
+         throw Invalid_Argument("String contains non-digit char: " + chrAsString);
          }
+      }
 
-      const auto integerValue = std::stoul(str);
+   const unsigned long int x = std::stoul(str);
 
-      // integerValue might be uint64
-      if (integerValue > std::numeric_limits<uint32_t>::max())
+   if(sizeof(unsigned long int) > 4)
+      {
+      // x might be uint64
+      if (x > std::numeric_limits<uint32_t>::max())
          {
-         throw Invalid_Argument("Integer value exceeds 32 bit range: " + std::to_string(integerValue));
+         throw Invalid_Argument("Integer value of " + str + " exceeds 32 bit range");
          }
-
-      return integerValue;
-      }
-   catch(std::exception& e)
-      {
-      auto message = std::string("Could not read '" + str + "' as decimal string");
-      auto exceptionMessage = std::string(e.what());
-      if (!exceptionMessage.empty()) message += ": " + exceptionMessage;
-      throw Exception(message);
       }
+
+   return static_cast<uint32_t>(x);
    }
 
 /*
diff --git a/src/lib/utils/parsing.h b/src/lib/utils/parsing.h
index 71f349126..f4936bd68 100644
--- a/src/lib/utils/parsing.h
+++ b/src/lib/utils/parsing.h
@@ -105,6 +105,13 @@ BOTAN_DLL bool x500_name_cmp(const std::string& name1,
 BOTAN_DLL uint32_t to_u32bit(const std::string& str);
 
 /**
+* Convert a string to a number
+* @param str the string to convert
+* @return number value of the string
+*/
+BOTAN_DLL uint16_t to_uint16(const std::string& str);
+
+/**
 * Convert a time specification to a number
 * @param timespec the time specification
 * @return number of seconds represented by timespec