1 files changed, 80 insertions, 33 deletions

diff --git a/source/fud_string.cpp b/source/fud_string.cpp
index 3a9aca0..82a9fe5 100644
--- a/source/fud_string.cpp
+++ b/source/fud_string.cpp
@@ -46,30 +46,37 @@ ssize_t cStringLength(const char* str, size_t maxLength)
     return size;
 }
 
-// NOLINTBEGIN(cppcoreguidelines-pro-type-reinterpret-cast)
-String::String(const utf8* cString) : String(reinterpret_cast<const char*>(cString))
-{
-}
-// NOLINTEND(cppcoreguidelines-pro-type-reinterpret-cast)
-
-String::String(const char* cString)
+StringResult String::makeFromCString(const char* cString)
 {
     auto lenResult = cStringLength(cString);
     if (lenResult < 0 || lenResult >= SSIZE_MAX) {
-        m_length = 1;
-        m_capacity = 0;
-    } else if (static_cast<size_t>(lenResult) < SSO_BUF_SIZE) {
-        m_length = static_cast<size_t>(lenResult);
-        fudAssert(copyMem(m_buffer.data(), m_buffer.size(), cString, m_length) == FudStatus::Success);
-        fudAssert(nullTerminate() == FudStatus::Success);
-    } else {
-        m_length = static_cast<size_t>(lenResult);
-        m_capacity = m_length + 1;
-        m_data = static_cast<utf8*>(fudAlloc(m_capacity));
-        fudAssert(m_data != nullptr);
-        fudAssert(copyMem(m_data, m_capacity, cString, m_length) == FudStatus::Success);
-        fudAssert(nullTerminate() == FudStatus::Success);
+        return StringResult::error(FudStatus::InvalidInput);
+    }
+
+    String output{};
+    auto* data = output.m_buffer.data();
+    output.m_length = static_cast<size_t>(lenResult);
+    if (output.m_length >= output.m_capacity) {
+        output.m_capacity = output.m_length + 1;
+        data = static_cast<utf8*>(fudAlloc(output.m_capacity));
+        if (data == nullptr) {
+            return StringResult::error(FudStatus::AllocFailure);
+        }
+        output.m_data = data;
     }
+    auto copyStatus = copyMem(data, output.m_capacity, cString, output.m_length);
+    fudAssert(copyStatus == FudStatus::Success);
+    auto terminateStatus = output.nullTerminate();
+    fudAssert(terminateStatus == FudStatus::Success);
+
+    return StringResult::okay(std::move(output));
+}
+
+StringResult String::makeFromUtf8(const utf8* utf8String)
+{
+    // NOLINTBEGIN(cppcoreguidelines-pro-type-reinterpret-cast)
+    return makeFromCString(reinterpret_cast<const char*>(utf8String));
+    // NOLINTEND(cppcoreguidelines-pro-type-reinterpret-cast)
 }
 
 String::String(const String& rhs) : m_length{rhs.m_length}, m_capacity{rhs.m_capacity}
@@ -364,7 +371,7 @@ FudStatus String::append(StringView source)
         return FudStatus::OperationInvalid;
     }
     const size_t newSize = newLength + 1; // cppcheck-suppress knownConditionTrueFalse
-    if (newSize < newLength) { // cppcheck-suppress knownConditionTrueFalse
+    if (newSize < newLength) {            // cppcheck-suppress knownConditionTrueFalse
         return FudStatus::OperationInvalid;
     }
     if (newSize >= m_capacity) {
@@ -386,22 +393,60 @@ FudStatus String::append(StringView source)
     return status;
 }
 
-String String::catenate(const char* rhs) const
+StringResult String::catenate(const char* rhs) const
 {
-    String rhsString{rhs};
-    return catenate(rhsString);
-}
+    if (!valid()) {
+        return StringResult::error(FudStatus::InvalidInput);
+    }
+
+    auto lenResult = cStringLength(rhs);
+    if (lenResult < 0 || lenResult >= SSIZE_MAX) {
+        return StringResult::error(FudStatus::InvalidInput);
+    }
+    size_t rhsLength = static_cast<size_t>(lenResult);
 
-String String::catenate(const String& rhs) const
-{
     String output{};
-    output.m_length = 1;
-    output.m_capacity = 0;
 
+    if (SIZE_MAX - m_length < rhsLength)
+    {
+        return StringResult::error(FudStatus::Failure);
+    }
+
+    output.m_length = m_length + rhsLength;
+    auto* destPtr = output.m_buffer.data();
+    if (output.m_length >= output.m_capacity) {
+        output.m_capacity = output.m_length + 1;
+        destPtr = static_cast<utf8*>(fudAlloc(output.m_capacity));
+        if (destPtr == nullptr) {
+            return StringResult::error(FudStatus::AllocFailure);
+        }
+        output.m_data = destPtr;
+    }
+
+    auto status = copyMem(destPtr, m_capacity, data(), length());
+    fudAssert(status == FudStatus::Success);
+
+    status = copyMem(destPtr + length(), output.m_capacity - length(), rhs, rhsLength);
+    fudAssert(status == FudStatus::Success);
+
+    auto terminateStatus = output.nullTerminate();
+    fudAssert(terminateStatus == FudStatus::Success);
+
+    return StringResult::okay(std::move(output));
+}
+
+StringResult String::catenate(const String& rhs) const
+{
     if (!valid() || !rhs.valid()) {
-        return output;
+        return StringResult::error(FudStatus::InvalidInput);
     }
 
+    if (SIZE_MAX - m_length < rhs.length())
+    {
+        return StringResult::error(FudStatus::Failure);
+    }
+
+    String output{};
     output.m_length = m_length + rhs.length();
     output.m_capacity = output.m_length + 1;
     if (output.m_capacity < SSO_BUF_SIZE) {
@@ -414,12 +459,14 @@ String String::catenate(const String& rhs) const
     auto* destPtr = output.data();
     auto status = copyMem(destPtr, m_capacity, data(), length());
     fudAssert(status == FudStatus::Success);
+
     status = copyMem(destPtr + length(), output.m_capacity - length(), rhs.data(), rhs.length());
     fudAssert(status == FudStatus::Success);
-    static_cast<void>(status);
-    fudAssert(output.nullTerminate() == FudStatus::Success);
 
-    return output;
+    auto terminateStatus = output.nullTerminate();
+    fudAssert(terminateStatus == FudStatus::Success);
+
+    return StringResult::okay(std::move(output));
 }
 
 bool String::compare(const String& rhs) const