1 // Copyright 2011 Google Inc. 2 // All rights reserved. 3 // 4 // Redistribution and use in source and binary forms, with or without 5 // modification, are permitted provided that the following conditions are 6 // met: 7 // 8 // * Redistributions of source code must retain the above copyright 9 // notice, this list of conditions and the following disclaimer. 10 // * Redistributions in binary form must reproduce the above copyright 11 // notice, this list of conditions and the following disclaimer in the 12 // documentation and/or other materials provided with the distribution. 13 // * Neither the name of Google Inc. nor the names of its contributors 14 // may be used to endorse or promote products derived from this software 15 // without specific prior written permission. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 29 #include "utils/stream.hpp" 30 31 #include <istream> 32 #include <sstream> 33 34 #include "utils/format/macros.hpp" 35 #include "utils/sanity.hpp" 36 37 38 /// Gets the length of a stream. 39 /// 40 /// \param is The input stream for which to calculate its length. 41 /// 42 /// \return The length of the stream. This is of size_t type instead of 43 /// directly std::streampos to simplify the caller. Some systems do not 44 /// support comparing a std::streampos directly to an integer (see 45 /// NetBSD 1.5.x), which is what we often want to do. 46 /// 47 /// \throw std::exception If calculating the length fails due to a stream error. 48 std::size_t 49 utils::stream_length(std::istream& is) 50 { 51 const std::streampos current_pos = is.tellg(); 52 try { 53 is.seekg(0, std::ios::end); 54 const std::streampos length = is.tellg(); 55 is.seekg(current_pos, std::ios::beg); 56 return static_cast< std::size_t >(length); 57 } catch (...) { 58 is.seekg(current_pos, std::ios::beg); 59 throw; 60 } 61 } 62 63 64 /// Reads the whole contents of a stream into memory. 65 /// 66 /// \param input The input stream from which to read. 67 /// 68 /// \return A plain string containing the raw contents of the file. 69 std::string 70 utils::read_stream(std::istream& input) 71 { 72 std::ostringstream buffer; 73 74 char tmp[1024]; 75 while (input.good()) { 76 input.read(tmp, sizeof(tmp)); 77 if (input.good() || input.eof()) { 78 buffer.write(tmp, input.gcount()); 79 } 80 } 81 82 return buffer.str(); 83 } 84