1 files changed, 191 insertions, 0 deletions
diff --git a/nss/cpputil/databuffer.h b/nss/cpputil/databuffer.h
new file mode 100644
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--- /dev/null
+++ b/nss/cpputil/databuffer.h
@@ -0,0 +1,191 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef databuffer_h__
+#define databuffer_h__
+
+#include <algorithm>
+#include <cassert>
+#include <cstring>
+#include <iomanip>
+#include <iostream>
+#if defined(WIN32) || defined(WIN64)
+#include <winsock2.h>
+#else
+#include <arpa/inet.h>
+#endif
+
+extern bool g_ssl_gtest_verbose;
+
+namespace nss_test {
+
+class DataBuffer {
+ public:
+  DataBuffer() : data_(nullptr), len_(0) {}
+  DataBuffer(const uint8_t* data, size_t len) : data_(nullptr), len_(0) {
+    Assign(data, len);
+  }
+  DataBuffer(const DataBuffer& other) : data_(nullptr), len_(0) {
+    Assign(other);
+  }
+  ~DataBuffer() { delete[] data_; }
+
+  DataBuffer& operator=(const DataBuffer& other) {
+    if (&other != this) {
+      Assign(other);
+    }
+    return *this;
+  }
+
+  void Allocate(size_t len) {
+    delete[] data_;
+    data_ = new uint8_t[len ? len : 1];  // Don't depend on new [0].
+    len_ = len;
+  }
+
+  void Truncate(size_t len) { len_ = (std::min)(len_, len); }
+
+  void Assign(const DataBuffer& other) { Assign(other.data(), other.len()); }
+
+  void Assign(const uint8_t* data, size_t len) {
+    if (data) {
+      Allocate(len);
+      memcpy(static_cast<void*>(data_), static_cast<const void*>(data), len);
+    } else {
+      assert(len == 0);
+      data_ = nullptr;
+      len_ = 0;
+    }
+  }
+
+  // Write will do a new allocation and expand the size of the buffer if needed.
+  // Returns the offset of the end of the write.
+  size_t Write(size_t index, const uint8_t* val, size_t count) {
+    assert(val);
+    if (index + count > len_) {
+      size_t newlen = index + count;
+      uint8_t* tmp = new uint8_t[newlen];  // Always > 0.
+      if (data_) {
+        memcpy(static_cast<void*>(tmp), static_cast<const void*>(data_), len_);
+      }
+      if (index > len_) {
+        memset(static_cast<void*>(tmp + len_), 0, index - len_);
+      }
+      delete[] data_;
+      data_ = tmp;
+      len_ = newlen;
+    }
+    if (data_) {
+      memcpy(static_cast<void*>(data_ + index), static_cast<const void*>(val),
+             count);
+    }
+    return index + count;
+  }
+
+  size_t Write(size_t index, const DataBuffer& buf) {
+    return Write(index, buf.data(), buf.len());
+  }
+
+  // Write an integer, also performing host-to-network order conversion.
+  // Returns the offset of the end of the write.
+  size_t Write(size_t index, uint32_t val, size_t count) {
+    assert(count <= sizeof(uint32_t));
+    uint32_t nvalue = htonl(val);
+    auto* addr = reinterpret_cast<const uint8_t*>(&nvalue);
+    return Write(index, addr + sizeof(uint32_t) - count, count);
+  }
+
+  // This can't use the same trick as Write(), since we might be reading from a
+  // smaller data source.
+  bool Read(size_t index, size_t count, uint32_t* val) const {
+    assert(count < sizeof(uint32_t));
+    assert(val);
+    if ((index > len()) || (count > (len() - index))) {
+      return false;
+    }
+    *val = 0;
+    for (size_t i = 0; i < count; ++i) {
+      *val = (*val << 8) | data()[index + i];
+    }
+    return true;
+  }
+
+  // Starting at |index|, remove |remove| bytes and replace them with the
+  // contents of |buf|.
+  void Splice(const DataBuffer& buf, size_t index, size_t remove = 0) {
+    Splice(buf.data(), buf.len(), index, remove);
+  }
+
+  void Splice(const uint8_t* ins, size_t ins_len, size_t index,
+              size_t remove = 0) {
+    assert(ins);
+    uint8_t* old_value = data_;
+    size_t old_len = len_;
+
+    // The amount of stuff remaining from the tail of the old.
+    size_t tail_len = old_len - (std::min)(old_len, index + remove);
+    // The new length: the head of the old, the new, and the tail of the old.
+    len_ = index + ins_len + tail_len;
+    data_ = new uint8_t[len_ ? len_ : 1];
+
+    // The head of the old.
+    if (old_value) {
+      Write(0, old_value, (std::min)(old_len, index));
+    }
+    // Maybe a gap.
+    if (old_value && index > old_len) {
+      memset(old_value + index, 0, index - old_len);
+    }
+    // The new.
+    Write(index, ins, ins_len);
+    // The tail of the old.
+    if (tail_len > 0) {
+      Write(index + ins_len, old_value + index + remove, tail_len);
+    }
+
+    delete[] old_value;
+  }
+
+  void Append(const DataBuffer& buf) { Splice(buf, len_); }
+
+  const uint8_t* data() const { return data_; }
+  uint8_t* data() { return data_; }
+  size_t len() const { return len_; }
+  bool empty() const { return len_ == 0; }
+
+ private:
+  uint8_t* data_;
+  size_t len_;
+};
+
+static const size_t kMaxBufferPrint = 32;
+
+inline std::ostream& operator<<(std::ostream& stream, const DataBuffer& buf) {
+  stream << "[" << buf.len() << "] ";
+  for (size_t i = 0; i < buf.len(); ++i) {
+    if (!g_ssl_gtest_verbose && i >= kMaxBufferPrint) {
+      stream << "...";
+      break;
+    }
+    stream << std::hex << std::setfill('0') << std::setw(2)
+           << static_cast<unsigned>(buf.data()[i]);
+  }
+  stream << std::dec;
+  return stream;
+}
+
+inline bool operator==(const DataBuffer& a, const DataBuffer& b) {
+  return (a.empty() && b.empty()) ||
+         (a.len() == b.len() && 0 == memcmp(a.data(), b.data(), a.len()));
+}
+
+inline bool operator!=(const DataBuffer& a, const DataBuffer& b) {
+  return !(a == b);
+}
+
+}  // namespace nss_test
+
+#endif