diff options
-rw-r--r-- | src/common/base58.cpp | 2 | ||||
-rw-r--r-- | src/common/util.cpp | 2 | ||||
-rw-r--r-- | src/common/util.h | 4 | ||||
-rw-r--r-- | src/common/varint.h | 112 |
4 files changed, 80 insertions, 40 deletions
diff --git a/src/common/base58.cpp b/src/common/base58.cpp index 9ea6ba1ba..b1b427ebf 100644 --- a/src/common/base58.cpp +++ b/src/common/base58.cpp @@ -99,7 +99,7 @@ namespace tools static decoded_block_sizes instance; private: - std::vector<int> m_data; + std::vector<int> m_data;p }; decoded_block_sizes decoded_block_sizes::instance; diff --git a/src/common/util.cpp b/src/common/util.cpp index d2ff90679..0ad1f0791 100644 --- a/src/common/util.cpp +++ b/src/common/util.cpp @@ -47,7 +47,7 @@ using namespace epee; namespace tools { - std::function<void(void)> signal_handler::m_handler; + std::function<void(void)> signal_handler::m_handler; #ifdef WIN32 std::string get_windows_version_display_string() diff --git a/src/common/util.h b/src/common/util.h index 876673d0a..a512eb0a3 100644 --- a/src/common/util.h +++ b/src/common/util.h @@ -136,8 +136,8 @@ namespace tools /*! \breif calles m_handler */ static void handle_signal() { - /* static std::mutex m_mutex; */ - /* std::unique_lock<std::mutex> lock(m_mutex); */ + static std::mutex m_mutex; + std::unique_lock<std::mutex> lock(m_mutex); m_handler(); } diff --git a/src/common/varint.h b/src/common/varint.h index dcb70d686..8d4b4cce8 100644 --- a/src/common/varint.h +++ b/src/common/varint.h @@ -35,54 +35,94 @@ #include <utility> #include <sstream> #include <string> +/*! \file varint.h + * \breif provides the implementation of varint's + * + * The representation of varints is rather odd. The first bit of each + * octet is significant, it represents wheter there is another part + * waiting to be read. For example 0x8002 would return 0x200, even + * though 0x02 does not have its msb set. The actual way they are read + * is as follows: Strip the msb of each byte, then from left to right, + * read in what remains, placing it in reverse, into the buffer. Thus, + * the following bit stream: 0xff02 would return 0x027f. 0xff turns + * into 0x7f, is placed on the beggining of the buffer, then 0x02 is + * unchanged, since its msb is not set, and placed at the end of the + * buffer. + */ namespace tools { - template<typename OutputIt, typename T> - typename std::enable_if<std::is_integral<T>::value && std::is_unsigned<T>::value, void>::type - write_varint(OutputIt &&dest, T i) { - while (i >= 0x80) { - *dest++ = (static_cast<char>(i) & 0x7f) | 0x80; - i >>= 7; - } - *dest++ = static_cast<char>(i); + /*! \breif Error codes for varint + */ + enum { + /* \breif Represents the overflow error */ + EVARINT_OVERFLOW = -1, + /* \breif Represents a non conical represnetation */ + EVARINT_REPRESENT = -2, + }; + + /*! \breif writes a varint to a stream. + */ + template<typename OutputIt, typename T> + /* Requires T to be both an integral type and unsigned, should be a compile error if it is not */ + typename std::enable_if<std::is_integral<T>::value && std::is_unsigned<T>::value, void>::type + write_varint(OutputIt &&dest, T i) { + /* Make sure that there is one after this */ + while (i >= 0x80) { + *dest = (static_cast<char>(i) & 0x7f) | 0x80; + ++dest; + i >>= 7; /* I should be in multiples of 7, this should just get the next part */ } + /* writes the last one to dest */ + *dest = static_cast<char>(i); + dest++; /* Seems kinda pointless... */ + } - template<typename t_type> - std::string get_varint_data(const t_type& v) + /*! \breif Returns the string that represents the varint + */ + template<typename T> + std::string get_varint_data(const T& v) { std::stringstream ss; write_varint(std::ostreambuf_iterator<char>(ss), v); return ss.str(); } - - template<int bits, typename InputIt, typename T> + /*! \breif reads in the varint as pointer to by InputIt into i + */ + template<int bits, typename InputIt, typename T> typename std::enable_if<std::is_integral<T>::value && std::is_unsigned<T>::value && 0 <= bits && bits <= std::numeric_limits<T>::digits, int>::type - read_varint(InputIt &&first, InputIt &&last, T &i) { - int read = 0; - i = 0; - for (int shift = 0;; shift += 7) { - if (first == last) { - return read; // End of input. - } - unsigned char byte = *first++; - ++read; - if (shift + 7 >= bits && byte >= 1 << (bits - shift)) { - return -1; // Overflow. - } - if (byte == 0 && shift != 0) { - return -2; // Non-canonical representation. - } - i |= static_cast<T>(byte & 0x7f) << shift; - if ((byte & 0x80) == 0) { - break; - } - } - return read; + read_varint(InputIt &&first, InputIt &&last, T &write) { + int read = 0; + write = 0; + for (int shift = 0;; shift += 7) { + if (first == last) { + return read; + } + unsigned char byte = *first; + ++first; + ++read; + if (shift + 7 >= bits && byte >= 1 << (bits - shift)) { + return EVARINT_OVERFLOW; + } + if (byte == 0 && shift != 0) { + return EVARINT_REPRESENT; + } + + write |= static_cast<T>(byte & 0x7f) << shift; /* Does the actualy placing into write, stripping the first bit */ + + /* If there is no next */ + if ((byte & 0x80) == 0) { + break; + } } + return read; + } - template<typename InputIt, typename T> + /*! \breif Wrapper around the other read_varint, + * Sets template parameters for you. + */ + template<typename InputIt, typename T> int read_varint(InputIt &&first, InputIt &&last, T &i) { - return read_varint<std::numeric_limits<T>::digits, InputIt, T>(std::move(first), std::move(last), i); - } + return read_varint<std::numeric_limits<T>::digits, InputIt, T>(std::move(first), std::move(last), i); + } } |