1 files changed, 63 insertions, 0 deletions
diff --git a/gfx/angle/checkout/src/compiler/translator/ImmutableStringBuilder.cpp b/gfx/angle/checkout/src/compiler/translator/ImmutableStringBuilder.cpp
new file mode 100644
index 0000000000..3c7c01041f
--- /dev/null
+++ b/gfx/angle/checkout/src/compiler/translator/ImmutableStringBuilder.cpp
@@ -0,0 +1,63 @@
+//
+// Copyright 2018 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+// ImmutableStringBuilder.cpp: Stringstream-like utility for building pool allocated strings where
+// the maximum length is known in advance.
+//
+
+#include "compiler/translator/ImmutableStringBuilder.h"
+
+#include <stdio.h>
+
+namespace sh
+{
+
+ImmutableStringBuilder &ImmutableStringBuilder::operator<<(const ImmutableString &str)
+{
+    ASSERT(mData != nullptr);
+    ASSERT(mPos + str.length() <= mMaxLength);
+    memcpy(mData + mPos, str.data(), str.length());
+    mPos += str.length();
+    return *this;
+}
+
+ImmutableStringBuilder &ImmutableStringBuilder::operator<<(const char *str)
+{
+    ASSERT(mData != nullptr);
+    size_t len = strlen(str);
+    ASSERT(mPos + len <= mMaxLength);
+    memcpy(mData + mPos, str, len);
+    mPos += len;
+    return *this;
+}
+
+ImmutableStringBuilder &ImmutableStringBuilder::operator<<(const char &c)
+{
+    ASSERT(mData != nullptr);
+    ASSERT(mPos + 1 <= mMaxLength);
+    mData[mPos++] = c;
+    return *this;
+}
+
+void ImmutableStringBuilder::appendDecimal(const uint32_t &u)
+{
+    int numChars = snprintf(mData + mPos, mMaxLength - mPos, "%d", u);
+    ASSERT(numChars >= 0);
+    ASSERT(mPos + numChars <= mMaxLength);
+    mPos += numChars;
+}
+
+ImmutableStringBuilder::operator ImmutableString()
+{
+    mData[mPos] = '\0';
+    ImmutableString str(static_cast<const char *>(mData), mPos);
+#if defined(ANGLE_ENABLE_ASSERTS)
+    // Make sure that nothing is added to the string after it is finalized.
+    mData = nullptr;
+#endif
+    return str;
+}
+
+}  // namespace sh