// Wrapper of C-language FILE struct -*- C++ -*- // Copyright (C) 2000-2017 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the // terms of the GNU General Public License as published by the // Free Software Foundation; either version 3, or (at your option) // any later version. // This library is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // Under Section 7 of GPL version 3, you are granted additional // permissions described in the GCC Runtime Library Exception, version // 3.1, as published by the Free Software Foundation. // You should have received a copy of the GNU General Public License and // a copy of the GCC Runtime Library Exception along with this program; // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see // . // // ISO C++ 14882: 27.8 File-based streams // #include #include #include #ifdef _GLIBCXX_HAVE_POLL #include #endif // Pick up ioctl on Solaris 2.8 #ifdef _GLIBCXX_HAVE_UNISTD_H #include #endif // Pick up FIONREAD on Solaris 2 #ifdef _GLIBCXX_HAVE_SYS_IOCTL_H #define BSD_COMP #include #endif // Pick up FIONREAD on Solaris 2.5. #ifdef _GLIBCXX_HAVE_SYS_FILIO_H #include #endif #ifdef _GLIBCXX_HAVE_SYS_UIO_H #include #endif #if defined(_GLIBCXX_HAVE_S_ISREG) || defined(_GLIBCXX_HAVE_S_IFREG) # include # ifdef _GLIBCXX_HAVE_S_ISREG # define _GLIBCXX_ISREG(x) S_ISREG(x) # else # define _GLIBCXX_ISREG(x) (((x) & S_IFMT) == S_IFREG) # endif #endif #include // For ::max() and min() and ::max() namespace { // Map ios_base::openmode flags to a string for use in fopen(). // Table of valid combinations as given in [lib.filebuf.members]/2. static const char* fopen_mode(std::ios_base::openmode mode) { enum { in = std::ios_base::in, out = std::ios_base::out, trunc = std::ios_base::trunc, app = std::ios_base::app, binary = std::ios_base::binary }; // _GLIBCXX_RESOLVE_LIB_DEFECTS // 596. 27.8.1.3 Table 112 omits "a+" and "a+b" modes. switch (mode & (in|out|trunc|app|binary)) { case ( out ): return "w"; case ( out |app ): return "a"; case ( app ): return "a"; case ( out|trunc ): return "w"; case (in ): return "r"; case (in|out ): return "r+"; case (in|out|trunc ): return "w+"; case (in|out |app ): return "a+"; case (in |app ): return "a+"; case ( out |binary): return "wb"; case ( out |app|binary): return "ab"; case ( app|binary): return "ab"; case ( out|trunc |binary): return "wb"; case (in |binary): return "rb"; case (in|out |binary): return "r+b"; case (in|out|trunc |binary): return "w+b"; case (in|out |app|binary): return "a+b"; case (in |app|binary): return "a+b"; default: return 0; // invalid } } // Wrapper handling partial write. static std::streamsize xwrite(int __fd, const char* __s, std::streamsize __n) { std::streamsize __nleft = __n; for (;;) { const std::streamsize __ret = write(__fd, __s, __nleft); if (__ret == -1L && errno == EINTR) continue; if (__ret == -1L) break; __nleft -= __ret; if (__nleft == 0) break; __s += __ret; } return __n - __nleft; } #ifdef _GLIBCXX_HAVE_WRITEV // Wrapper handling partial writev. static std::streamsize xwritev(int __fd, const char* __s1, std::streamsize __n1, const char* __s2, std::streamsize __n2) { std::streamsize __nleft = __n1 + __n2; std::streamsize __n1_left = __n1; struct iovec __iov[2]; __iov[1].iov_base = const_cast(__s2); __iov[1].iov_len = __n2; for (;;) { __iov[0].iov_base = const_cast(__s1); __iov[0].iov_len = __n1_left; const std::streamsize __ret = writev(__fd, __iov, 2); if (__ret == -1L && errno == EINTR) continue; if (__ret == -1L) break; __nleft -= __ret; if (__nleft == 0) break; const std::streamsize __off = __ret - __n1_left; if (__off >= 0) { __nleft -= xwrite(__fd, __s2 + __off, __n2 - __off); break; } __s1 += __ret; __n1_left -= __ret; } return __n1 + __n2 - __nleft; } #endif } // anonymous namespace namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION // Definitions for __basic_file. __basic_file::__basic_file(__c_lock* /*__lock*/) throw() : _M_cfile(NULL), _M_cfile_created(false) { } __basic_file::~__basic_file() { this->close(); } __basic_file* __basic_file::sys_open(__c_file* __file, ios_base::openmode __mode) { __basic_file* __ret = NULL; if (!this->is_open() && __file) { int __err, __save_errno = errno; // POSIX guarantees that fflush sets errno on error, but C doesn't. errno = 0; do __err = (__mode == std::ios_base::in ? 0 : fflush(__file)); while (__err && errno == EINTR); errno = __save_errno; if (!__err) { _M_cfile = __file; _M_cfile_created = false; __ret = this; } } return __ret; } __basic_file* __basic_file::sys_open(int __fd, ios_base::openmode __mode) throw () { __basic_file* __ret = NULL; const char* __c_mode = fopen_mode(__mode); if (__c_mode && !this->is_open() && (_M_cfile = fdopen(__fd, __c_mode))) { char* __buf = NULL; _M_cfile_created = true; if (__fd == 0) setvbuf(_M_cfile, __buf, _IONBF, 0); __ret = this; } return __ret; } __basic_file* __basic_file::open(const char* __name, ios_base::openmode __mode, int /*__prot*/) { __basic_file* __ret = NULL; const char* __c_mode = fopen_mode(__mode); if (__c_mode && !this->is_open()) { #ifdef _GLIBCXX_USE_LFS if ((_M_cfile = fopen64(__name, __c_mode))) #else if ((_M_cfile = fopen(__name, __c_mode))) #endif { _M_cfile_created = true; __ret = this; } } return __ret; } bool __basic_file::is_open() const throw () { return _M_cfile != 0; } int __basic_file::fd() throw () { return fileno(_M_cfile); } __c_file* __basic_file::file() throw () { return _M_cfile; } __basic_file* __basic_file::close() { __basic_file* __ret = static_cast<__basic_file*>(NULL); if (this->is_open()) { int __err = 0; if (_M_cfile_created) __err = fclose(_M_cfile); _M_cfile = 0; if (!__err) __ret = this; } return __ret; } streamsize __basic_file::xsgetn(char* __s, streamsize __n) { streamsize __ret; do __ret = read(this->fd(), __s, __n); while (__ret == -1L && errno == EINTR); return __ret; } streamsize __basic_file::xsputn(const char* __s, streamsize __n) { return xwrite(this->fd(), __s, __n); } streamsize __basic_file::xsputn_2(const char* __s1, streamsize __n1, const char* __s2, streamsize __n2) { streamsize __ret = 0; #ifdef _GLIBCXX_HAVE_WRITEV __ret = xwritev(this->fd(), __s1, __n1, __s2, __n2); #else if (__n1) __ret = xwrite(this->fd(), __s1, __n1); if (__ret == __n1) __ret += xwrite(this->fd(), __s2, __n2); #endif return __ret; } streamoff __basic_file::seekoff(streamoff __off, ios_base::seekdir __way) throw () { #ifdef _GLIBCXX_USE_LFS return lseek64(this->fd(), __off, __way); #else if (__off > numeric_limits::max() || __off < numeric_limits::min()) return -1L; return lseek(this->fd(), __off, __way); #endif } int __basic_file::sync() { return fflush(_M_cfile); } streamsize __basic_file::showmanyc() { #ifndef _GLIBCXX_NO_IOCTL #ifdef FIONREAD // Pipes and sockets. int __num = 0; int __r = ioctl(this->fd(), FIONREAD, &__num); if (!__r && __num >= 0) return __num; #endif #endif #ifdef _GLIBCXX_HAVE_POLL // Cheap test. struct pollfd __pfd[1]; __pfd[0].fd = this->fd(); __pfd[0].events = POLLIN; if (poll(__pfd, 1, 0) <= 0) return 0; #endif #if defined(_GLIBCXX_HAVE_S_ISREG) || defined(_GLIBCXX_HAVE_S_IFREG) // Regular files. #ifdef _GLIBCXX_USE_LFS struct stat64 __buffer; const int __err = fstat64(this->fd(), &__buffer); if (!__err && _GLIBCXX_ISREG(__buffer.st_mode)) { const streamoff __off = __buffer.st_size - lseek64(this->fd(), 0, ios_base::cur); return std::min(__off, streamoff(numeric_limits::max())); } #else struct stat __buffer; const int __err = fstat(this->fd(), &__buffer); if (!__err && _GLIBCXX_ISREG(__buffer.st_mode)) return __buffer.st_size - lseek(this->fd(), 0, ios_base::cur); #endif #endif return 0; } _GLIBCXX_END_NAMESPACE_VERSION } // namespace