66 lines · cpp
1//===--- Implementation of a platform independent Dir data structure ------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "dir.h"10 11#include "src/__support/CPP/mutex.h" // lock_guard12#include "src/__support/CPP/new.h"13#include "src/__support/error_or.h"14#include "src/__support/libc_errno.h" // For error macros15#include "src/__support/macros/config.h"16 17namespace LIBC_NAMESPACE_DECL {18 19ErrorOr<Dir *> Dir::open(const char *path) {20 auto fd = platform_opendir(path);21 if (!fd)22 return LIBC_NAMESPACE::Error(fd.error());23 24 LIBC_NAMESPACE::AllocChecker ac;25 Dir *dir = new (ac) Dir(fd.value());26 if (!ac)27 return LIBC_NAMESPACE::Error(ENOMEM);28 return dir;29}30 31ErrorOr<struct ::dirent *> Dir::read() {32 cpp::lock_guard lock(mutex);33 if (readptr >= fillsize) {34 auto readsize = platform_fetch_dirents(fd, buffer);35 if (!readsize)36 return LIBC_NAMESPACE::Error(readsize.error());37 fillsize = readsize.value();38 readptr = 0;39 }40 if (fillsize == 0)41 return nullptr;42 43 struct ::dirent *d = reinterpret_cast<struct ::dirent *>(buffer + readptr);44#ifdef __linux__45 // The d_reclen field is available on Linux but not required by POSIX.46 readptr += d->d_reclen;47#else48 // Other platforms have to implement how the read pointer is to be updated.49#error "DIR read pointer update is missing."50#endif51 return d;52}53 54int Dir::close() {55 {56 cpp::lock_guard lock(mutex);57 int retval = platform_closedir(fd);58 if (retval != 0)59 return retval;60 }61 delete this;62 return 0;63}64 65} // namespace LIBC_NAMESPACE_DECL66