From f8b84a3b8c5eff26114008ababc333c7d14c92de Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Tue, 21 Mar 2017 14:43:03 +0100 Subject: Move istringstream_nocopy to a separate file --- src/libutil/hash.cc | 2 +- src/libutil/istringstream_nocopy.hh | 92 +++++++++++++++++++++++++++++++++++++ src/libutil/util.hh | 88 ----------------------------------- 3 files changed, 93 insertions(+), 89 deletions(-) create mode 100644 src/libutil/istringstream_nocopy.hh (limited to 'src/libutil') diff --git a/src/libutil/hash.cc b/src/libutil/hash.cc index a8bbcf8c1754..9f4afd93c2fc 100644 --- a/src/libutil/hash.cc +++ b/src/libutil/hash.cc @@ -7,12 +7,12 @@ #include "hash.hh" #include "archive.hh" #include "util.hh" +#include "istringstream_nocopy.hh" #include #include #include - namespace nix { diff --git a/src/libutil/istringstream_nocopy.hh b/src/libutil/istringstream_nocopy.hh new file mode 100644 index 000000000000..f7beac578e39 --- /dev/null +++ b/src/libutil/istringstream_nocopy.hh @@ -0,0 +1,92 @@ +/* This file provides a variant of std::istringstream that doesn't + copy its string argument. This is useful for large strings. The + caller must ensure that the string object is not destroyed while + it's referenced by this object. */ + +#pragma once + +#include +#include + +template , class Allocator = std::allocator> +class basic_istringbuf_nocopy : public std::basic_streambuf +{ +public: + typedef std::basic_string string_type; + + typedef typename std::basic_streambuf::off_type off_type; + + typedef typename std::basic_streambuf::pos_type pos_type; + + typedef typename std::basic_streambuf::int_type int_type; + + typedef typename std::basic_streambuf::traits_type traits_type; + +private: + const string_type & s; + + off_type off; + +public: + basic_istringbuf_nocopy(const string_type & s) : s{s}, off{0} + { + } + +private: + pos_type seekoff(off_type off, std::ios_base::seekdir dir, std::ios_base::openmode which) + { + if (which & std::ios_base::in) { + this->off = dir == std::ios_base::beg + ? off + : (dir == std::ios_base::end + ? s.size() + off + : this->off + off); + } + return pos_type(this->off); + } + + pos_type seekpos(pos_type pos, std::ios_base::openmode which) + { + return seekoff(pos, std::ios_base::beg, which); + } + + std::streamsize showmanyc() + { + return s.size() - off; + } + + int_type underflow() + { + if (typename string_type::size_type(off) == s.size()) + return traits_type::eof(); + return traits_type::to_int_type(s[off]); + } + + int_type uflow() + { + if (typename string_type::size_type(off) == s.size()) + return traits_type::eof(); + return traits_type::to_int_type(s[off++]); + } + + int_type pbackfail(int_type ch) + { + if (off == 0 || (ch != traits_type::eof() && ch != s[off - 1])) + return traits_type::eof(); + + return traits_type::to_int_type(s[--off]); + } + +}; + +template , class Allocator = std::allocator> +class basic_istringstream_nocopy : public std::basic_iostream +{ + typedef basic_istringbuf_nocopy buf_type; + buf_type buf; +public: + basic_istringstream_nocopy(const typename buf_type::string_type & s) : + std::basic_iostream(&buf), buf(s) {}; +}; + +typedef basic_istringstream_nocopy istringstream_nocopy; diff --git a/src/libutil/util.hh b/src/libutil/util.hh index 645289f67c9a..0e6941e4a8db 100644 --- a/src/libutil/util.hh +++ b/src/libutil/util.hh @@ -451,92 +451,4 @@ struct ReceiveInterrupts { } }; - -template , class Allocator = std::allocator> -class basic_istringbuf_nocopy : public std::basic_streambuf -{ -public: - typedef std::basic_string string_type; - - typedef typename std::basic_streambuf::off_type off_type; - - typedef typename std::basic_streambuf::pos_type pos_type; - - typedef typename std::basic_streambuf::int_type int_type; - - typedef typename std::basic_streambuf::traits_type traits_type; - -private: - const string_type & s; - - off_type off; - -public: - basic_istringbuf_nocopy(const string_type & s) : s{s}, off{0} - { - } - -private: - pos_type seekoff(off_type off, std::ios_base::seekdir dir, std::ios_base::openmode which) - { - if (which & std::ios_base::in) { - this->off = dir == std::ios_base::beg - ? off - : (dir == std::ios_base::end - ? s.size() + off - : this->off + off); - } - return pos_type(this->off); - } - - pos_type seekpos(pos_type pos, std::ios_base::openmode which) - { - return seekoff(pos, std::ios_base::beg, which); - } - - std::streamsize showmanyc() - { - return s.size() - off; - } - - int_type underflow() - { - if (typename string_type::size_type(off) == s.size()) - return traits_type::eof(); - return traits_type::to_int_type(s[off]); - } - - int_type uflow() - { - if (typename string_type::size_type(off) == s.size()) - return traits_type::eof(); - return traits_type::to_int_type(s[off++]); - } - - int_type pbackfail(int_type ch) - { - if (off == 0 || (ch != traits_type::eof() && ch != s[off - 1])) - return traits_type::eof(); - - return traits_type::to_int_type(s[--off]); - } - -}; - -template , class Allocator = std::allocator> -class basic_istringstream_nocopy : public std::basic_iostream -{ - typedef basic_istringbuf_nocopy buf_type; - buf_type buf; -public: - basic_istringstream_nocopy(const typename buf_type::string_type & s) : - std::basic_iostream(&buf), buf(s) {}; -}; - -/* A variant of std::istringstream that doesn't its string - argument. This is useful for large strings. The caller must ensure - that the string object is not destroyed while it's referenced by - this object. */ -typedef basic_istringstream_nocopy istringstream_nocopy; - } -- cgit 1.4.1