Add wrappers for reinterpret_cast between char* and uint8_t*

Generally speaking reinterpret_cast is sketchy stuff. But the
special case of char*/uint8_t* is both common and safe. By
isolating those, the remaining (likely sketchy) cases are easier
to grep for.

3 files changed, 5 insertions, 5 deletions

diff --git a/src/lib/math/bigint/big_code.cpp b/src/lib/math/bigint/big_code.cpp
index f7ab53291..c42819965 100644
--- a/src/lib/math/bigint/big_code.cpp
+++ b/src/lib/math/bigint/big_code.cpp
@@ -26,7 +26,7 @@ void BigInt::encode(uint8_t output[], const BigInt& n, Base base)
       secure_vector<uint8_t> binary(n.encoded_size(Binary));
       n.binary_encode(binary.data());
 
-      hex_encode(reinterpret_cast<char*>(output),
+      hex_encode(cast_uint8_ptr_to_char(output),
                  binary.data(), binary.size());
       }
    else if(base == Decimal)
@@ -128,12 +128,12 @@ BigInt BigInt::decode(const uint8_t buf[], size_t length, Base base)
 
          binary = hex_decode_locked(buf0_with_leading_0, 2);
 
-         binary += hex_decode_locked(reinterpret_cast<const char*>(&buf[1]),
+         binary += hex_decode_locked(cast_uint8_ptr_to_char(&buf[1]),
                                      length - 1,
                                      false);
          }
       else
-         binary = hex_decode_locked(reinterpret_cast<const char*>(buf),
+         binary = hex_decode_locked(cast_uint8_ptr_to_char(buf),
                                     length, false);
 
       r.binary_decode(binary.data(), binary.size());
diff --git a/src/lib/math/bigint/big_io.cpp b/src/lib/math/bigint/big_io.cpp
index 7d990e25e..803e1cc4a 100644
--- a/src/lib/math/bigint/big_io.cpp
+++ b/src/lib/math/bigint/big_io.cpp
@@ -32,7 +32,7 @@ std::ostream& operator<<(std::ostream& stream, const BigInt& n)
       size_t skip = 0;
       while(skip < buffer.size() && buffer[skip] == '0')
          ++skip;
-      stream.write(reinterpret_cast<const char*>(buffer.data()) + skip,
+      stream.write(cast_uint8_ptr_to_char(buffer.data()) + skip,
                    buffer.size() - skip);
       }
    if(!stream.good())
diff --git a/src/lib/math/bigint/bigint.cpp b/src/lib/math/bigint/bigint.cpp
index 47ff2482a..28fe68f00 100644
--- a/src/lib/math/bigint/bigint.cpp
+++ b/src/lib/math/bigint/bigint.cpp
@@ -68,7 +68,7 @@ BigInt::BigInt(const std::string& str)
       base = Hexadecimal;
       }
 
-   *this = decode(reinterpret_cast<const uint8_t*>(str.data()) + markers,
+   *this = decode(cast_char_ptr_to_uint8(str.data()) + markers,
                   str.length() - markers, base);
 
    if(negative) set_sign(Negative);