Remove now unused Balsa code.

net/tools/balsa/balsa_headers.h

Index: net/tools/balsa/balsa_headers.h
diff --git a/net/tools/balsa/balsa_headers.h b/net/tools/balsa/balsa_headers.h
deleted file mode 100644
index d796e9a86acf2f616e93747f40b34752af9e861a..0000000000000000000000000000000000000000
--- a/net/tools/balsa/balsa_headers.h
+++ /dev/null
@@ -1,1143 +0,0 @@
-// Copyright 2013 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef NET_TOOLS_BALSA_BALSA_HEADERS_H_
-#define NET_TOOLS_BALSA_BALSA_HEADERS_H_
-
-#include <stddef.h>
-
-#include <algorithm>
-#include <iosfwd>
-#include <iterator>
-#include <string>
-#include <utility>
-#include <vector>
-
-#include "base/logging.h"
-#include "base/strings/string_piece.h"
-#include "net/tools/balsa/balsa_enums.h"
-#include "net/tools/balsa/string_piece_utils.h"
-
-namespace net {
-
-// WARNING:
-// Note that -no- char* returned by any function in this
-// file is null-terminated.
-
-// This class exists to service the specific needs of BalsaHeaders.
-//
-// Functional goals:
-//   1) provide a backing-store for all of the StringPieces that BalsaHeaders
-//      returns. Every StringPiece returned from BalsaHeaders should remain
-//      valid until the BalsaHeader's object is cleared, or the header-line is
-//      erased.
-//   2) provide a backing-store for BalsaFrame, which requires contiguous memory
-//      for its fast-path parsing functions. Note that the cost of copying is
-//      less than the cost of requiring the parser to do slow-path parsing, as
-//      it would have to check for bounds every byte, instead of every 16 bytes.
-//
-// This class is optimized for the case where headers are stored in one of two
-// buffers. It doesn't make a lot of effort to densely pack memory-- in fact,
-// it -may- be somewhat memory inefficient. This possible inefficiency allows a
-// certain simplicity of implementation and speed which makes it worthwhile.
-// If, in the future, better memory density is required, it should be possible
-// to reuse the abstraction presented by this object to achieve those goals.
-//
-// In the most common use-case, this memory inefficiency should be relatively
-// small.
-//
-// Alternate implementations of BalsaBuffer may include:
-//  - vector of strings, one per header line (similar to HTTPHeaders)
-//  - densely packed strings:
-//    - keep a sorted array/map of free-space linked lists or numbers.
-//      - use the entry that most closely first your needs.
-//    - at this point, perhaps just use a vector of strings, and let
-//      the allocator do the right thing.
-//
-class BalsaBuffer {
- public:
-  static const size_t kDefaultBlocksize = 4096;
-  // We have two friends here. These exist as friends as we
-  // want to allow access to the constructors for the test
-  // class and the Balsa* classes. We put this into the
-  // header file as we want this class to be inlined into the
-  // BalsaHeaders implementation, yet be testable.
-  friend class BalsaBufferTestSpouse;
-  friend class BalsaHeaders;
-  friend class BalsaBufferTest;
-
-  // The BufferBlock is a structure used internally by the
-  // BalsaBuffer class to store the base buffer pointers to
-  // each block, as well as the important metadata for buffer
-  // sizes and bytes free.
-  struct BufferBlock {
-   public:
-    char* buffer;
-    size_t buffer_size;
-    size_t bytes_free;
-
-    size_t bytes_used() const {
-      return buffer_size - bytes_free;
-    }
-    char* start_of_unused_bytes() const {
-      return buffer + bytes_used();
-    }
-
-    BufferBlock() : buffer(NULL), buffer_size(0), bytes_free(0) {}
-    ~BufferBlock() {}
-
-    BufferBlock(char* buf, size_t size, size_t free) :
-        buffer(buf), buffer_size(size), bytes_free(free) {}
-    // Yes we want this to be copyable (it gets stuck into vectors).
-    // For this reason, we don't use scoped ptrs, etc. here-- it
-    // is more efficient to manage this memory externally to this
-    // object.
-  };
-
-  typedef std::vector<BufferBlock> Blocks;
-
-  ~BalsaBuffer();
-
-  // Returns the total amount of memory used by the buffer blocks.
-  size_t GetTotalBufferBlockSize() const;
-
-  const char* GetPtr(Blocks::size_type block_idx) const {
-    DCHECK_LT(block_idx, blocks_.size())
-      << block_idx << ", " << blocks_.size();
-    return blocks_[block_idx].buffer;
-  }
-
-  char* GetPtr(Blocks::size_type block_idx) {
-    DCHECK_LT(block_idx, blocks_.size())
-      << block_idx << ", " << blocks_.size();
-    return blocks_[block_idx].buffer;
-  }
-
-  // This function is different from Write(), as it ensures that the data
-  // stored via subsequent calls to this function are all contiguous (and in
-  // the order in which these writes happened). This is essentially the same
-  // as a string append.
-  //
-  // You may call this function at any time between object
-  // construction/Clear(), and the calling of the
-  // NoMoreWriteToContiguousBuffer() function.
-  //
-  // You must not call this function after the NoMoreWriteToContiguousBuffer()
-  // function is called, unless a Clear() has been called since.
-  // If you do, the program will abort().
-  //
-  // This condition is placed upon this code so that calls to Write() can
-  // append to the buffer in the first block safely, and without invaliding
-  // the StringPiece which it returns.
-  //
-  // This function's main intended user is the BalsaFrame class, which,
-  // for reasons of efficiency, requires that the buffer from which it parses
-  // the headers be contiguous.
-  //
-  void WriteToContiguousBuffer(const base::StringPiece& sp);
-
-  void NoMoreWriteToContiguousBuffer() {
-    can_write_to_contiguous_buffer_ = false;
-  }
-
-  // Takes a StringPiece and writes it to "permanent" storage, then returns a
-  // StringPiece which points to that data.  If block_idx != NULL, it will be
-  // assigned the index of the block into which the data was stored.
-  // Note that the 'permanent' storage in which it stores data may be in
-  // the first block IFF the NoMoreWriteToContiguousBuffer function has
-  // been called since the last Clear/Construction.
-  base::StringPiece Write(const base::StringPiece& sp,
-                          Blocks::size_type* block_buffer_idx);
-
-  // Reserves "permanent" storage of the size indicated. Returns a pointer to
-  // the beginning of that storage, and assigns the index of the block used to
-  // block_buffer_idx. This function uses the first block IFF the
-  // NoMoreWriteToContiguousBuffer function has been called since the last
-  // Clear/Construction.
-  char* Reserve(size_t size, Blocks::size_type* block_buffer_idx);
-
-  void Clear();
-
-  void Swap(BalsaBuffer* b);
-
-  void CopyFrom(const BalsaBuffer& b);
-
-  const char* StartOfFirstBlock() const {
-    return blocks_[0].buffer;
-  }
-
-  const char* EndOfFirstBlock() const {
-    return blocks_[0].buffer + blocks_[0].bytes_used();
-  }
-
-  bool can_write_to_contiguous_buffer() const {
-    return can_write_to_contiguous_buffer_;
-  }
-  size_t blocksize() const { return blocksize_; }
-  Blocks::size_type num_blocks() const { return blocks_.size(); }
-  size_t buffer_size(size_t idx) const { return blocks_[idx].buffer_size; }
-  size_t bytes_used(size_t idx) const { return blocks_[idx].bytes_used(); }
-
- protected:
-  BalsaBuffer();
-
-  explicit BalsaBuffer(size_t blocksize);
-
-  BufferBlock AllocBlock();
-
-  BufferBlock AllocCustomBlock(size_t blocksize);
-
-  BufferBlock CopyBlock(const BufferBlock& b);
-
-  // Cleans up the object.
-  // The block at start_idx, and all subsequent blocks
-  // will be cleared and have associated memory deleted.
-  void CleanupBlocksStartingFrom(Blocks::size_type start_idx);
-
-  // A container of BufferBlocks
-  Blocks blocks_;
-
-  // The default allocation size for a block.
-  // In general, blocksize_ bytes will be allocated for
-  // each buffer.
-  size_t blocksize_;
-
-  // If set to true, then the first block cannot be used for Write() calls as
-  // the WriteToContiguous... function will modify the base pointer for this
-  // block, and the Write() calls need to be sure that the base pointer will
-  // not be changing in order to provide the user with StringPieces which
-  // continue to be valid.
-  bool can_write_to_contiguous_buffer_;
-};
-
-////////////////////////////////////////////////////////////////////////////////
-
-// All of the functions in the BalsaHeaders class use string pieces, by either
-// using the StringPiece class, or giving an explicit size and char* (as these
-// are the native representation for these string pieces).
-// This is done for several reasons.
-//  1) This minimizes copying/allocation/deallocation as compared to using
-//  string parameters
-//  2) This reduces the number of strlen() calls done (as the length of any
-//  string passed in is relatively likely to be known at compile time, and for
-//  those strings passed back we obviate the need for a strlen() to determine
-//  the size of new storage allocations if a new allocation is required.
-//  3) This class attempts to store all of its data in two linear buffers in
-//  order to enhance the speed of parsing and writing out to a buffer. As a
-//  result, many string pieces are -not- terminated by '\0', and are not
-//  c-strings.  Since this is the case, we must delineate the length of the
-//  string explicitly via a length.
-//
-//  WARNING:  The side effect of using StringPiece is that if the underlying
-//  buffer changes (due to modifying the headers) the StringPieces which point
-//  to the data which was modified, may now contain "garbage", and should not
-//  be dereferenced.
-//  For example, If you fetch some component of the first-line, (request or
-//  response), and then you modify the first line, the StringPieces you
-//  originally received from the original first-line may no longer be valid).
-//
-//  StringPieces pointing to pieces of header lines which have not been
-//  erased() or modified should be valid until the object is cleared or
-//  destroyed.
-
-class BalsaHeaders {
- public:
-  struct HeaderLineDescription {
-    HeaderLineDescription(size_t first_character_index,
-                          size_t key_end_index,
-                          size_t value_begin_index,
-                          size_t last_character_index,
-                          size_t buffer_base_index) :
-        first_char_idx(first_character_index),
-        key_end_idx(key_end_index),
-        value_begin_idx(value_begin_index),
-        last_char_idx(last_character_index),
-        buffer_base_idx(buffer_base_index),
-        skip(false) {}
-
-    HeaderLineDescription() :
-        first_char_idx(0),
-        key_end_idx(0),
-        value_begin_idx(0),
-        last_char_idx(0),
-        buffer_base_idx(0),
-        skip(false) {}
-
-    size_t first_char_idx;
-    size_t key_end_idx;
-    size_t value_begin_idx;
-    size_t last_char_idx;
-    BalsaBuffer::Blocks::size_type buffer_base_idx;
-    bool skip;
-  };
-
-  typedef std::vector<base::StringPiece> HeaderTokenList;
-  friend bool ParseHTTPFirstLine(const char* begin,
-                                 const char* end,
-                                 bool is_request,
-                                 size_t max_request_uri_length,
-                                 BalsaHeaders* headers,
-                                 BalsaFrameEnums::ErrorCode* error_code);
-
- protected:
-  typedef std::vector<HeaderLineDescription> HeaderLines;
-
-  // Why these base classes (iterator_base, reverse_iterator_base)?  Well, if
-  // we do want to export both iterator and const_iterator types (currently we
-  // only have const_iterator), then this is useful to avoid code duplication.
-  // Additionally, having this base class makes comparisons of iterators of
-  // different types (they're different types to ensure that operator= and
-  // constructors do not work in the places where they're expected to not work)
-  // work properly. There could be as many as 4 iterator types, all based on
-  // the same data as iterator_base... so it makes sense to simply have some
-  // base classes.
-
-  class iterator_base {
-   public:
-    friend class BalsaHeaders;
-    friend class reverse_iterator_base;
-    typedef std::pair<base::StringPiece, base::StringPiece> StringPiecePair;
-    typedef StringPiecePair value_type;
-    typedef value_type& reference;
-    typedef value_type* pointer;
-
-    typedef std::forward_iterator_tag iterator_category;
-    typedef ptrdiff_t difference_type;
-
-    typedef iterator_base self;
-
-    // default constructor.
-    iterator_base();
-
-    // copy constructor.
-    iterator_base(const iterator_base& it);
-
-    reference operator*() const {
-      return Lookup(idx_);
-    }
-
-    pointer operator->() const {
-      return &(this->operator*());
-    }
-
-    bool operator==(const self& it) const {
-      return idx_ == it.idx_;
-    }
-
-    bool operator<(const self& it) const {
-      return idx_ < it.idx_;
-    }
-
-    bool operator<=(const self& it) const {
-      return idx_ <= it.idx_;
-    }
-
-    bool operator!=(const self& it) const {
-      return !(*this == it);
-    }
-
-    bool operator>(const self& it) const {
-      return it < *this;
-    }
-
-    bool operator>=(const self& it) const {
-      return it <= *this;
-    }
-
-    // This mainly exists so that we can have interesting output for
-    // unittesting. The EXPECT_EQ, EXPECT_NE functions require that
-    // operator<< work for the classes it sees.  It would be better if there
-    // was an additional traits-like system for the gUnit output... but oh
-    // well.
-    std::ostream& operator<<(std::ostream& os) const;
-
-   protected:
-    iterator_base(const BalsaHeaders* headers, HeaderLines::size_type index);
-
-    void increment() {
-      const HeaderLines& header_lines = headers_->header_lines_;
-      const HeaderLines::size_type header_lines_size = header_lines.size();
-      const HeaderLines::size_type original_idx = idx_;
-      do {
-        ++idx_;
-      } while (idx_ < header_lines_size && header_lines[idx_].skip == true);
-      // The condition below exists so that ++(end() - 1) == end(), even
-      // if there are only 'skip == true' elements between the end() iterator
-      // and the end of the vector of HeaderLineDescriptions.
-      // TODO(fenix): refactor this list so that we don't have to do
-      // linear scanning through skipped headers (and this condition is
-      // then unnecessary)
-      if (idx_ == header_lines_size) {
-        idx_ = original_idx + 1;
-      }
-    }
-
-    void decrement() {
-      const HeaderLines& header_lines = headers_->header_lines_;
-      const HeaderLines::size_type header_lines_size = header_lines.size();
-      const HeaderLines::size_type original_idx = idx_;
-      do {
-        --idx_;
-      } while (idx_ < header_lines_size && header_lines[idx_].skip == true);
-      // The condition below exists so that --(rbegin() + 1) == rbegin(), even
-      // if there are only 'skip == true' elements between the rbegin() iterator
-      // and the beginning of the vector of HeaderLineDescriptions.
-      // TODO(fenix): refactor this list so that we don't have to do
-      // linear scanning through skipped headers (and this condition is
-      // then unnecessary)
-      if (idx_ > header_lines_size) {
-        idx_ = original_idx - 1;
-      }
-    }
-
-    reference Lookup(HeaderLines::size_type index) const {
-      DCHECK_LT(index, headers_->header_lines_.size());
-      const HeaderLineDescription& line = headers_->header_lines_[index];
-      const char* stream_begin = headers_->GetPtr(line.buffer_base_idx);
-      value_ = value_type(
-          base::StringPiece(stream_begin + line.first_char_idx,
-                      line.key_end_idx - line.first_char_idx),
-          base::StringPiece(stream_begin + line.value_begin_idx,
-                      line.last_char_idx - line.value_begin_idx));
-      DCHECK_GE(line.key_end_idx, line.first_char_idx);
-      DCHECK_GE(line.last_char_idx, line.value_begin_idx);
-      return value_;
-    }
-
-    const BalsaHeaders* headers_;
-    HeaderLines::size_type idx_;
-    mutable StringPiecePair value_;
-  };
-
-  class reverse_iterator_base : public iterator_base {
-   public:
-    typedef reverse_iterator_base self;
-    typedef iterator_base::reference reference;
-    typedef iterator_base::pointer pointer;
-    using iterator_base::headers_;
-    using iterator_base::idx_;
-
-    reverse_iterator_base() : iterator_base() {}
-
-    // This constructor is no explicit purposely.
-    reverse_iterator_base(const iterator_base& it) :  // NOLINT
-        iterator_base(it) {
-    }
-
-    self& operator=(const iterator_base& it) {
-      idx_ = it.idx_;
-      headers_ = it.headers_;
-      return *this;
-    }
-
-    self& operator=(const reverse_iterator_base& it) {
-      idx_ = it.idx_;
-      headers_ = it.headers_;
-      return *this;
-    }
-
-    reference operator*() const {
-      return Lookup(idx_ - 1);
-    }
-
-    pointer operator->() const {
-      return &(this->operator*());
-    }
-
-    reverse_iterator_base(const reverse_iterator_base& it) :
-        iterator_base(it) { }
-
-   protected:
-    void increment() {
-      --idx_;
-      iterator_base::decrement();
-      ++idx_;
-    }
-
-    void decrement() {
-      ++idx_;
-      iterator_base::increment();
-      --idx_;
-    }
-
-    reverse_iterator_base(const BalsaHeaders* headers,
-                          HeaderLines::size_type index) :
-        iterator_base(headers, index) {}
-  };
-
- public:
-  class const_header_lines_iterator : public iterator_base {
-    friend class BalsaHeaders;
-   public:
-    typedef const_header_lines_iterator self;
-    const_header_lines_iterator() : iterator_base() {}
-
-    const_header_lines_iterator(const const_header_lines_iterator& it) :
-        iterator_base(it.headers_, it.idx_) {}
-
-    self& operator++() {
-      iterator_base::increment();
-      return *this;
-    }
-
-    self& operator--() {
-      iterator_base::decrement();
-      return *this;
-    }
-   protected:
-    const_header_lines_iterator(const BalsaHeaders* headers,
-                                HeaderLines::size_type index) :
-        iterator_base(headers, index) {}
-  };
-
-  class const_reverse_header_lines_iterator : public reverse_iterator_base {
-   public:
-    typedef const_reverse_header_lines_iterator self;
-    const_reverse_header_lines_iterator() : reverse_iterator_base() {}
-
-    const_reverse_header_lines_iterator(
-      const const_header_lines_iterator& it) :
-        reverse_iterator_base(it.headers_, it.idx_) {}
-
-    const_reverse_header_lines_iterator(
-      const const_reverse_header_lines_iterator& it) :
-        reverse_iterator_base(it.headers_, it.idx_) {}
-
-    const_header_lines_iterator base() {
-      return const_header_lines_iterator(headers_, idx_);
-    }
-
-    self& operator++() {
-      reverse_iterator_base::increment();
-      return *this;
-    }
-
-    self& operator--() {
-      reverse_iterator_base::decrement();
-      return *this;
-    }
-   protected:
-    const_reverse_header_lines_iterator(const BalsaHeaders* headers,
-                                        HeaderLines::size_type index) :
-        reverse_iterator_base(headers, index) {}
-
-    friend class BalsaHeaders;
-  };
-
-  // An iterator that only stops at lines with a particular key.
-  // See also GetIteratorForKey.
-  //
-  // Check against header_lines_key_end() to determine when iteration is
-  // finished. header_lines_end() will also work.
-  class const_header_lines_key_iterator : public iterator_base {
-    friend class BalsaHeaders;
-   public:
-    typedef const_header_lines_key_iterator self;
-    const_header_lines_key_iterator(const const_header_lines_key_iterator&);
-
-    self& operator++() {
-      do {
-        iterator_base::increment();
-      } while (!AtEnd() &&
-               !base::EqualsCaseInsensitiveASCII(key_, (**this).first));
-      return *this;
-    }
-
-    void operator++(int ignore) {
-      ++(*this);
-    }
-
-    // Only forward-iteration makes sense, so no operator-- defined.
-
-   private:
-    const_header_lines_key_iterator(const BalsaHeaders* headers,
-                                    HeaderLines::size_type index,
-                                    const base::StringPiece& key);
-
-    // Should only be used for creating an end iterator.
-    const_header_lines_key_iterator(const BalsaHeaders* headers,
-                                    HeaderLines::size_type index);
-
-    bool AtEnd() const {
-      return *this >= headers_->header_lines_end();
-    }
-
-    base::StringPiece key_;
-  };
-
-  // TODO(fenix): Revisit the amount of bytes initially allocated to the second
-  // block of the balsa_buffer_. It may make sense to pre-allocate some amount
-  // (roughly the amount we'd append in new headers such as X-User-Ip, etc.)
-  BalsaHeaders();
-  ~BalsaHeaders();
-
-  const_header_lines_iterator header_lines_begin() {
-    return HeaderLinesBeginHelper<const_header_lines_iterator>();
-  }
-
-  const_header_lines_iterator header_lines_begin() const {
-    return HeaderLinesBeginHelper<const_header_lines_iterator>();
-  }
-
-  const_header_lines_iterator header_lines_end() {
-    return HeaderLinesEndHelper<const_header_lines_iterator>();
-  }
-
-  const_header_lines_iterator header_lines_end() const {
-    return HeaderLinesEndHelper<const_header_lines_iterator>();
-  }
-
-  const_reverse_header_lines_iterator header_lines_rbegin() {
-    return const_reverse_header_lines_iterator(header_lines_end());
-  }
-
-  const_reverse_header_lines_iterator header_lines_rbegin() const {
-    return const_reverse_header_lines_iterator(header_lines_end());
-  }
-
-  const_reverse_header_lines_iterator header_lines_rend() {
-    return const_reverse_header_lines_iterator(header_lines_begin());
-  }
-
-  const_reverse_header_lines_iterator header_lines_rend() const {
-    return const_reverse_header_lines_iterator(header_lines_begin());
-  }
-
-  const_header_lines_key_iterator header_lines_key_end() const {
-    return HeaderLinesEndHelper<const_header_lines_key_iterator>();
-  }
-
-  void erase(const const_header_lines_iterator& it) {
-    DCHECK_EQ(it.headers_, this);
-    DCHECK_LT(it.idx_, header_lines_.size());
-    DCHECK_GE(it.idx_, 0u);
-    header_lines_[it.idx_].skip = true;
-  }
-
-  void Clear();
-
-  void Swap(BalsaHeaders* other);
-
-  void CopyFrom(const BalsaHeaders& other);
-
-  void HackHeader(const base::StringPiece& key, const base::StringPiece& value);
-
-  // Same as AppendToHeader, except that it will attempt to preserve
-  // header ordering.
-  // Note that this will always append to an existing header, if available,
-  // without moving the header around, or collapsing multiple header lines
-  // with the same key together. For this reason, it only 'attempts' to
-  // preserve header ordering.
-  // TODO(fenix): remove this function and rename all occurances
-  // of it in the code to AppendToHeader when the condition above
-  // has been satisified.
-  void HackAppendToHeader(const base::StringPiece& key,
-                          const base::StringPiece& value);
-
-  // Replaces header entries with key 'key' if they exist, or appends
-  // a new header if none exist.  See 'AppendHeader' below for additional
-  // comments about ContentLength and TransferEncoding headers. Note that this
-  // will allocate new storage every time that it is called.
-  // TODO(fenix): modify this function to reuse existing storage
-  // if it is available.
-  void ReplaceOrAppendHeader(const base::StringPiece& key,
-                             const base::StringPiece& value);
-
-  // Append a new header entry to the header object. Clients who wish to append
-  // Content-Length header should use SetContentLength() method instead of
-  // adding the content length header using AppendHeader (manually adding the
-  // content length header will not update the content_length_ and
-  // content_length_status_ values).
-  // Similarly, clients who wish to add or remove the transfer encoding header
-  // in order to apply or remove chunked encoding should use SetChunkEncoding()
-  // instead.
-  void AppendHeader(const base::StringPiece& key,
-                    const base::StringPiece& value);
-
-  // Appends ',value' to an existing header named 'key'.  If no header with the
-  // correct key exists, it will call AppendHeader(key, value).  Calling this
-  // function on a key which exists several times in the headers will produce
-  // unpredictable results.
-  void AppendToHeader(const base::StringPiece& key,
-                      const base::StringPiece& value);
-
-  // Prepends 'value,' to an existing header named 'key'.  If no header with the
-  // correct key exists, it will call AppendHeader(key, value).  Calling this
-  // function on a key which exists several times in the headers will produce
-  // unpredictable results.
-  void PrependToHeader(const base::StringPiece& key,
-                       const base::StringPiece& value);
-
-  const base::StringPiece GetHeader(const base::StringPiece& key) const;
-
-  // Iterates over all currently valid header lines, appending their
-  // values into the vector 'out', in top-to-bottom order.
-  // Header-lines which have been erased are not currently valid, and
-  // will not have their values appended. Empty values will be
-  // represented as empty string. If 'key' doesn't exist in the headers at
-  // all, out will not be changed. We do not clear the vector out
-  // before adding new entries. If there are header lines with matching
-  // key but empty value then they are also added to the vector out.
-  // (Basically empty values are not treated in any special manner).
-  //
-  // Example:
-  // Input header:
-  // "GET / HTTP/1.0\r\n"
-  //    "key1: v1\r\n"
-  //    "key1: \r\n"
-  //    "key1:\r\n"
-  //    "key1:  v1\r\n"
-  //    "key1:v2\r\n"
-  //
-  //  vector out is initially: ["foo"]
-  //  vector out after GetAllOfHeader("key1", &out) is:
-  // ["foo", "v1", "", "", "v2", "v1", "v2"]
-
-  void GetAllOfHeader(const base::StringPiece& key,
-                      std::vector<base::StringPiece>* out) const;
-
-  // Joins all values for key into a comma-separated string in out.
-  // More efficient than calling JoinStrings on result of GetAllOfHeader if
-  // you don't need the intermediate vector<StringPiece>.
-  void GetAllOfHeaderAsString(const base::StringPiece& key,
-                              std::string* out) const;
-
-  // Returns true if RFC 2616 Section 14 indicates that header can
-  // have multiple values.
-  static bool IsMultivaluedHeader(const base::StringPiece& header);
-
-  // Determine if a given header is present.
-  inline bool HasHeader(const base::StringPiece& key) const {
-    return (GetConstHeaderLinesIterator(key, header_lines_.begin()) !=
-            header_lines_.end());
-  }
-
-  // Returns true iff any header 'key' exists with non-empty value.
-  bool HasNonEmptyHeader(const base::StringPiece& key) const;
-
-  const_header_lines_iterator GetHeaderPosition(
-      const base::StringPiece& key) const;
-
-  // Returns a forward-only iterator that only stops at lines matching key.
-  // String backing 'key' must remain valid for lifetime of iterator.
-  //
-  // Check returned iterator against header_lines_key_end() to determine when
-  // iteration is finished.
-  const_header_lines_key_iterator GetIteratorForKey(
-      const base::StringPiece& key) const;
-
-  void RemoveAllOfHeader(const base::StringPiece& key);
-
-  // Removes all headers starting with 'key' [case insensitive]
-  void RemoveAllHeadersWithPrefix(const base::StringPiece& key);
-
-  // Returns the lower bound of memory  used by this header object, including
-  // all internal buffers and data structure. Some of the memory used cannot be
-  // directly measure. For example, memory used for bookkeeping by standard
-  // containers.
-  size_t GetMemoryUsedLowerBound() const;
-
-  // Returns the upper bound on the required buffer space to fully write out
-  // the header object (this include the first line, all header lines, and the
-  // final CRLF that marks the ending of the header).
-  size_t GetSizeForWriteBuffer() const;
-
-  // The following WriteHeader* methods are template member functions that
-  // place one requirement on the Buffer class: it must implement a Write
-  // method that takes a pointer and a length. The buffer passed in is not
-  // required to be stretchable. For non-stretchable buffers, the user must
-  // call GetSizeForWriteBuffer() to find out the upper bound on the output
-  // buffer space required to make sure that the entire header is serialized.
-  // BalsaHeaders will not check that there is adequate space in the buffer
-  // object during the write.
-
-  // Writes the entire header and the final CRLF that marks the end of the HTTP
-  // header section to the buffer. After this method returns, no more header
-  // data should be written to the buffer.
-  template <typename Buffer>
-  void WriteHeaderAndEndingToBuffer(Buffer* buffer) const {
-    WriteToBuffer(buffer);
-    WriteHeaderEndingToBuffer(buffer);
-  }
-
-  // Writes the final CRLF to the buffer to terminate the HTTP header section.
-  // After this method returns, no more header data should be written to the
-  // buffer.
-  template <typename Buffer>
-  static void WriteHeaderEndingToBuffer(Buffer* buffer) {
-    buffer->Write("\r\n", 2);
-  }
-
-  // Writes the entire header to the buffer without the CRLF that terminates
-  // the HTTP header. This lets users append additional header lines using
-  // WriteHeaderLineToBuffer and then terminate the header with
-  // WriteHeaderEndingToBuffer as the header is serialized to the
-  // buffer, without having to first copy the header.
-  template <typename Buffer>
-  void WriteToBuffer(Buffer* buffer) const {
-    // write the first line.
-    const size_t firstline_len = whitespace_4_idx_ - non_whitespace_1_idx_;
-    const char* stream_begin = GetPtr(firstline_buffer_base_idx_);
-    buffer->Write(stream_begin + non_whitespace_1_idx_, firstline_len);
-    buffer->Write("\r\n", 2);
-    const HeaderLines::size_type end = header_lines_.size();
-    for (HeaderLines::size_type i = 0; i < end; ++i) {
-      const HeaderLineDescription& line = header_lines_[i];
-      if (line.skip) {
-        continue;
-      }
-      const char* line_ptr = GetPtr(line.buffer_base_idx);
-      WriteHeaderLineToBuffer(
-          buffer,
-          base::StringPiece(line_ptr + line.first_char_idx,
-                      line.key_end_idx - line.first_char_idx),
-          base::StringPiece(line_ptr + line.value_begin_idx,
-                      line.last_char_idx - line.value_begin_idx));
-    }
-  }
-
-  // Takes a header line in the form of a key/value pair and append it to the
-  // buffer. This function should be called after WriteToBuffer to
-  // append additional header lines to the header without copying the header.
-  // When the user is done with appending to the buffer,
-  // WriteHeaderEndingToBuffer must be used to terminate the HTTP
-  // header in the buffer. This method is a no-op if key is empty.
-  template <typename Buffer>
-  static void WriteHeaderLineToBuffer(Buffer* buffer,
-                                      const base::StringPiece& key,
-                                      const base::StringPiece& value) {
-    // if the key is empty, we don't want to write the rest because it
-    // will not be a well-formed header line.
-    if (!key.empty()) {
-      buffer->Write(key.data(), key.size());
-      buffer->Write(": ", 2);
-      buffer->Write(value.data(), value.size());
-      buffer->Write("\r\n", 2);
-    }
-  }
-
-  // Dump the textural representation of the header object to a string, which
-  // is suitable for writing out to logs. All CRLF will be printed out as \n.
-  // This function can be called on a header object in any state. The header
-  // content is appended to the string; the original content is not cleared.
-  void DumpHeadersToString(std::string* str) const;
-
-  // Calls DumpHeadersToString to dump the textural representation of the header
-  // object to a string. Raw header data will be printed out if the header
-  // object is not completely parsed, e.g., when there was an error in the
-  // middle of parsing.
-  void DumpToString(std::string* str) const;
-  std::string DebugString() const;
-
-  const base::StringPiece first_line() const {
-    DCHECK_GE(whitespace_4_idx_, non_whitespace_1_idx_);
-    return base::StringPiece(BeginningOfFirstLine() + non_whitespace_1_idx_,
-                       whitespace_4_idx_ - non_whitespace_1_idx_);
-  }
-
-  // Returns the parsed value of the response code if it has been parsed.
-  // Guaranteed to return 0 when unparsed (though it is a much better idea to
-  // verify that the BalsaFrame had no errors while parsing).
-  // This may return response codes which are outside the normal bounds of
-  // HTTP response codes-- it is up to the user of this class to ensure that
-  // the response code is one which is interpretable.
-  size_t parsed_response_code() const { return parsed_response_code_; }
-
-  const base::StringPiece request_method() const {
-    DCHECK_GE(whitespace_2_idx_, non_whitespace_1_idx_);
-    return base::StringPiece(BeginningOfFirstLine() + non_whitespace_1_idx_,
-                       whitespace_2_idx_ - non_whitespace_1_idx_);
-  }
-
-  const base::StringPiece response_version() const {
-    // Note: There is no difference between request_method() and
-    // response_version(). They both could be called
-    // GetFirstTokenFromFirstline()... but that wouldn't be anywhere near as
-    // descriptive.
-    return request_method();
-  }
-
-  const base::StringPiece request_uri() const {
-    DCHECK_GE(whitespace_3_idx_, non_whitespace_2_idx_);
-    return base::StringPiece(BeginningOfFirstLine() + non_whitespace_2_idx_,
-                       whitespace_3_idx_ - non_whitespace_2_idx_);
-  }
-
-  const base::StringPiece response_code() const {
-    // Note: There is no difference between request_uri() and response_code().
-    // They both could be called GetSecondtTokenFromFirstline(), but, as noted
-    // in an earlier comment, that wouldn't be as descriptive.
-    return request_uri();
-  }
-
-  const base::StringPiece request_version() const {
-    DCHECK_GE(whitespace_4_idx_, non_whitespace_3_idx_);
-    return base::StringPiece(BeginningOfFirstLine() + non_whitespace_3_idx_,
-                       whitespace_4_idx_ - non_whitespace_3_idx_);
-  }
-
-  const base::StringPiece response_reason_phrase() const {
-    // Note: There is no difference between request_version() and
-    // response_reason_phrase(). They both could be called
-    // GetThirdTokenFromFirstline(), but, as noted in an earlier comment, that
-    // wouldn't be as descriptive.
-    return request_version();
-  }
-
-  // Note that SetFirstLine will not update the internal indices for the
-  // various bits of the first-line (and may set them all to zero).
-  // If you'd like to use the accessors for the various bits of the firstline,
-  // then you should use the Set* functions, or SetFirstlineFromStringPieces,
-  // below, instead.
-  //
-  void SetFirstlineFromStringPieces(const base::StringPiece& firstline_a,
-                                    const base::StringPiece& firstline_b,
-                                    const base::StringPiece& firstline_c);
-
-  void SetRequestFirstlineFromStringPieces(const base::StringPiece& method,
-                                           const base::StringPiece& uri,
-                                           const base::StringPiece& version) {
-    SetFirstlineFromStringPieces(method, uri, version);
-  }
-
-  void SetResponseFirstlineFromStringPieces(
-      const base::StringPiece& version,
-      const base::StringPiece& code,
-      const base::StringPiece& reason_phrase) {
-    SetFirstlineFromStringPieces(version, code, reason_phrase);
-  }
-
-  // These functions are exactly the same, except that their names are
-  // different. This is done so that the code using this class is more
-  // expressive.
-  void SetRequestMethod(const base::StringPiece& method);
-  void SetResponseVersion(const base::StringPiece& version);
-
-  void SetRequestUri(const base::StringPiece& uri);
-  void SetResponseCode(const base::StringPiece& code);
-  void set_parsed_response_code(size_t parsed_response_code) {
-    parsed_response_code_ = parsed_response_code;
-  }
-  void SetParsedResponseCodeAndUpdateFirstline(size_t parsed_response_code);
-
-  // These functions are exactly the same, except that their names are
-  // different. This is done so that the code using this class is more
-  // expressive.
-  void SetRequestVersion(const base::StringPiece& version);
-  void SetResponseReasonPhrase(const base::StringPiece& reason_phrase);
-
-  // The biggest problem with SetFirstLine is that we don't want to use a
-  // separate buffer for it.  The second biggest problem with it is that the
-  // first biggest problem requires that we store offsets into a buffer instead
-  // of pointers into a buffer. Cuteness aside, SetFirstLine doesn't parse
-  // the individual fields of the firstline, and so accessors to those fields
-  // will not work properly after calling SetFirstLine. If you want those
-  // accessors to work, use the Set* functions above this one.
-  // SetFirstLine is stuff useful, however, if all you care about is correct
-  // serialization with the rest of the header object.
-  void SetFirstLine(const base::StringPiece& line);
-
-  // Simple accessors to some of the internal state
-  bool transfer_encoding_is_chunked() const {
-    return transfer_encoding_is_chunked_;
-  }
-
-  static bool ResponseCodeImpliesNoBody(size_t code) {
-    // From HTTP spec section 6.1.1 all 1xx responses must not have a body,
-    // as well as 204 No Content and 304 Not Modified.
-    return ((code >= 100) && (code <= 199)) || (code == 204) || (code == 304);
-  }
-
-  // Note: never check this for requests. Nothing bad will happen if you do,
-  // but spec does not allow requests framed by connection close.
-  // TODO(vitaliyl): refactor.
-  bool is_framed_by_connection_close() const {
-    // We declare that response is framed by connection close if it has no
-    // content-length, no transfer encoding, and is allowed to have a body by
-    // the HTTP spec.
-    // parsed_response_code_ is 0 for requests, so ResponseCodeImpliesNoBody
-    // will return false.
-    return (content_length_status_ == BalsaHeadersEnums::NO_CONTENT_LENGTH) &&
-        !transfer_encoding_is_chunked_ &&
-        !ResponseCodeImpliesNoBody(parsed_response_code_);
-  }
-
-  size_t content_length() const { return content_length_; }
-  BalsaHeadersEnums::ContentLengthStatus content_length_status() const {
-    return content_length_status_;
-  }
-
-  // SetContentLength and SetChunkEncoding modifies the header object to use
-  // content-length and transfer-encoding headers in a consistent manner. They
-  // set all internal flags and status so client can get a consistent view from
-  // various accessors.
-  void SetContentLength(size_t length);
-  void SetChunkEncoding(bool chunk_encode);
-
- protected:
-  friend class BalsaFrame;
-  friend class SpdyFrame;
-  friend class HTTPMessage;
-  friend class BalsaHeadersTokenUtils;
-
-  const char* BeginningOfFirstLine() const {
-    return GetPtr(firstline_buffer_base_idx_);
-  }
-
-  char* GetPtr(BalsaBuffer::Blocks::size_type block_idx) {
-    return balsa_buffer_.GetPtr(block_idx);
-  }
-
-  const char* GetPtr(BalsaBuffer::Blocks::size_type block_idx) const {
-    return balsa_buffer_.GetPtr(block_idx);
-  }
-
-  void WriteFromFramer(const char* ptr, size_t size) {
-    balsa_buffer_.WriteToContiguousBuffer(base::StringPiece(ptr, size));
-  }
-
-  void DoneWritingFromFramer() {
-    balsa_buffer_.NoMoreWriteToContiguousBuffer();
-  }
-
-  const char* OriginalHeaderStreamBegin() const {
-    return balsa_buffer_.StartOfFirstBlock();
-  }
-
-  const char* OriginalHeaderStreamEnd() const {
-    return balsa_buffer_.EndOfFirstBlock();
-  }
-
-  size_t GetReadableBytesFromHeaderStream() const {
-    return OriginalHeaderStreamEnd() - OriginalHeaderStreamBegin();
-  }
-
-  void GetReadablePtrFromHeaderStream(const char** p, size_t* s) {
-    *p = OriginalHeaderStreamBegin();
-    *s = GetReadableBytesFromHeaderStream();
-  }
-
-  base::StringPiece GetValueFromHeaderLineDescription(
-      const HeaderLineDescription& line) const;
-
-  void AddAndMakeDescription(const base::StringPiece& key,
-                             const base::StringPiece& value,
-                             HeaderLineDescription* d);
-
-  void AppendOrPrependAndMakeDescription(const base::StringPiece& key,
-                                         const base::StringPiece& value,
-                                         bool append,
-                                         HeaderLineDescription* d);
-
-  // Removes all header lines with the given key starting at start.
-  void RemoveAllOfHeaderStartingAt(const base::StringPiece& key,
-                                   HeaderLines::iterator start);
-
-  // If the 'key' does not exist in the headers, calls
-  // AppendHeader(key, value).  Otherwise if append is true, appends ',value'
-  // to the first existing header with key 'key'.  If append is false, prepends
-  // 'value,' to the first existing header with key 'key'.
-  void AppendOrPrependToHeader(const base::StringPiece& key,
-                               const base::StringPiece& value,
-                               bool append);
-
-  HeaderLines::const_iterator GetConstHeaderLinesIterator(
-      const base::StringPiece& key,
-      HeaderLines::const_iterator start) const;
-
-  HeaderLines::iterator GetHeaderLinesIteratorNoSkip(
-      const base::StringPiece& key,
-      HeaderLines::iterator start);
-
-  HeaderLines::iterator GetHeaderLinesIterator(
-      const base::StringPiece& key,
-      HeaderLines::iterator start);
-
-  template <typename IteratorType>
-  const IteratorType HeaderLinesBeginHelper() const {
-    if (header_lines_.empty()) {
-      return IteratorType(this, 0);
-    }
-    const HeaderLines::size_type header_lines_size = header_lines_.size();
-    for (HeaderLines::size_type i = 0; i < header_lines_size; ++i) {
-      if (header_lines_[i].skip == false) {
-        return IteratorType(this, i);
-      }
-    }
-    return IteratorType(this, 0);
-  }
-
-  template <typename IteratorType>
-  const IteratorType HeaderLinesEndHelper() const {
-    if (header_lines_.empty()) {
-      return IteratorType(this, 0);
-    }
-    const HeaderLines::size_type header_lines_size = header_lines_.size();
-    HeaderLines::size_type i = header_lines_size;
-    do {
-      --i;
-      if (header_lines_[i].skip == false) {
-        return IteratorType(this, i + 1);
-      }
-    } while (i != 0);
-    return IteratorType(this, 0);
-  }
-
-  // At the moment, this function will always return the original headers.
-  // In the future, it may not do so after erasing header lines, modifying
-  // header lines, or modifying the first line.
-  // For this reason, it is strongly suggested that use of this function is
-  // only acceptable for the purpose of debugging parse errors seen by the
-  // BalsaFrame class.
-  base::StringPiece OriginalHeadersForDebugging() const {
-    return base::StringPiece(OriginalHeaderStreamBegin(),
-                       OriginalHeaderStreamEnd() - OriginalHeaderStreamBegin());
-  }
-
-  BalsaBuffer balsa_buffer_;
-
-  size_t content_length_;
-  BalsaHeadersEnums::ContentLengthStatus content_length_status_;
-  size_t parsed_response_code_;
-  // HTTP firstlines all have the following structure:
-  //  LWS         NONWS  LWS    NONWS   LWS    NONWS   NOTCRLF  CRLF
-  //  [\t \r\n]+ [^\t ]+ [\t ]+ [^\t ]+ [\t ]+ [^\t ]+ [^\r\n]+ "\r\n"
-  //  ws1        nws1    ws2    nws2    ws3    nws3             ws4
-  //  |          [-------)      [-------)      [----------------)
-  //    REQ:     method         request_uri    version
-  //   RESP:     version        statuscode     reason
-  //
-  //   The first NONWS->LWS component we'll call firstline_a.
-  //   The second firstline_b, and the third firstline_c.
-  //
-  //   firstline_a goes from nws1 to (but not including) ws2
-  //   firstline_b goes from nws2 to (but not including) ws3
-  //   firstline_c goes from nws3 to (but not including) ws4
-  //
-  // In the code:
-  //    ws1 == whitespace_1_idx_
-  //   nws1 == non_whitespace_1_idx_
-  //    ws2 == whitespace_2_idx_
-  //   nws2 == non_whitespace_2_idx_
-  //    ws3 == whitespace_3_idx_
-  //   nws3 == non_whitespace_3_idx_
-  //    ws4 == whitespace_4_idx_
-  BalsaBuffer::Blocks::size_type firstline_buffer_base_idx_;
-  size_t whitespace_1_idx_;
-  size_t non_whitespace_1_idx_;
-  size_t whitespace_2_idx_;
-  size_t non_whitespace_2_idx_;
-  size_t whitespace_3_idx_;
-  size_t non_whitespace_3_idx_;
-  size_t whitespace_4_idx_;
-  size_t end_of_firstline_idx_;
-
-  bool transfer_encoding_is_chunked_;
-
-  HeaderLines header_lines_;
-};
-
-}  // namespace net
-
-#endif  // NET_TOOLS_BALSA_BALSA_HEADERS_H_