diff options
Diffstat (limited to 'na/fs/fd.cc')
| -rw-r--r-- | na/fs/fd.cc | 216 |
1 files changed, 0 insertions, 216 deletions
diff --git a/na/fs/fd.cc b/na/fs/fd.cc deleted file mode 100644 index 5fc8ab0..0000000 --- a/na/fs/fd.cc +++ /dev/null @@ -1,216 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-or-later */ -/* Copyright (C) 2026 Richard Qin */ - -/* - * fd.cc — File descriptor table management - */ - -#include <lume/fdtable.h> -#include <lume/file.h> -#include <lume/slab.h> -#include <lume/errno.h> - -/* ================================================================== */ -/* Bitmap helpers */ -/* ================================================================== */ - -static inline bool bit_test(const uint64* bmap, int bit) { - return (bmap[bit / 64] >> (bit % 64)) & 1; -} -static inline void bit_set(uint64* bmap, int bit) { - bmap[bit / 64] |= (1ULL << (bit % 64)); -} -static inline void bit_clear(uint64* bmap, int bit) { - bmap[bit / 64] &= ~(1ULL << (bit % 64)); -} - -/* ================================================================== */ -/* alloc_files_struct */ -/* ================================================================== */ - -files_struct* alloc_files_struct() -{ - auto* files = new files_struct{}; - if (!files) return nullptr; - - files->count.store(1); - files->next_fd = 0; - files->max_fds = NR_OPEN_DEFAULT; - - for (int i = 0; i < NR_OPEN_DEFAULT; i++) - files->fd_array[i] = nullptr; - - int bmap_words = (NR_OPEN_DEFAULT + 63) / 64; - for (int i = 0; i < bmap_words; i++) { - files->close_on_exec_init[i] = 0; - files->open_fds_init[i] = 0; - } - - return files; -} - -/* ================================================================== */ -/* put_files_struct — drop reference, free on last */ -/* ================================================================== */ - -void put_files_struct(files_struct* files) -{ - if (!files) return; - - int old = files->count.fetch_sub(1); - if (old > 1) return; - - /* Close all open fds */ - for (int i = 0; i < files->max_fds; i++) { - if (files->fd_array[i]) { - fput(files->fd_array[i]); - files->fd_array[i] = nullptr; - } - } - - delete files; -} - -/* ================================================================== */ -/* dup_fd — duplicate entire fd table (for fork) */ -/* ================================================================== */ - -files_struct* dup_fd(files_struct* old_files) -{ - auto* new_files = alloc_files_struct(); - if (!new_files) return nullptr; - - LockGuard guard(old_files->file_lock); - - for (int i = 0; i < old_files->max_fds; i++) { - file* fp = old_files->fd_array[i]; - if (fp) { - get_file(fp); - new_files->fd_array[i] = fp; - } - } - - /* Copy bitmaps */ - int bmap_words = (NR_OPEN_DEFAULT + 63) / 64; - for (int i = 0; i < bmap_words; i++) { - new_files->open_fds_init[i] = old_files->open_fds_init[i]; - new_files->close_on_exec_init[i] = old_files->close_on_exec_init[i]; - } - - new_files->next_fd = old_files->next_fd; - - return new_files; -} - -/* ================================================================== */ -/* alloc_fd — find lowest free fd >= start */ -/* ================================================================== */ - -int alloc_fd(files_struct* files, unsigned int start) -{ - LockGuard guard(files->file_lock); - - for (int fd = static_cast<int>(start); fd < files->max_fds; fd++) { - if (!bit_test(files->open_fds_init, fd)) { - bit_set(files->open_fds_init, fd); - files->fd_array[fd] = nullptr; /* placeholder, fd_install sets real file */ - if (fd >= files->next_fd) - files->next_fd = fd + 1; - return fd; - } - } - - return -EMFILE; -} - -/* ================================================================== */ -/* fd_install — place a file* at a given fd */ -/* ================================================================== */ - -void fd_install(files_struct* files, int fd, file* fp) -{ - LockGuard guard(files->file_lock); - files->fd_array[fd] = fp; -} - -/* ================================================================== */ -/* fcheck — look up file by fd (no refcount bump) */ -/* ================================================================== */ - -file* fcheck(files_struct* files, int fd) -{ - if (fd < 0 || fd >= files->max_fds) return nullptr; - return files->fd_array[fd]; -} - -/* ================================================================== */ -/* close_fd */ -/* ================================================================== */ - -int close_fd(files_struct* files, int fd) -{ - file* fp; - { - LockGuard guard(files->file_lock); - if (fd < 0 || fd >= files->max_fds) return -EBADF; - - fp = files->fd_array[fd]; - if (!fp) return -EBADF; - - files->fd_array[fd] = nullptr; - bit_clear(files->open_fds_init, fd); - bit_clear(files->close_on_exec_init, fd); - } - - fput(fp); - return 0; -} - -/* ================================================================== */ -/* do_dup2 — duplicate oldfd to newfd */ -/* ================================================================== */ - -int do_dup2(files_struct* files, int oldfd, int newfd, int flags) -{ - if (oldfd == newfd) return -EINVAL; - - file* existing = nullptr; - { - LockGuard guard(files->file_lock); - - if (oldfd < 0 || oldfd >= files->max_fds) return -EBADF; - if (newfd < 0 || newfd >= files->max_fds) return -EBADF; - - file* old_fp = files->fd_array[oldfd]; - if (!old_fp) return -EBADF; - - existing = files->fd_array[newfd]; - - get_file(old_fp); - files->fd_array[newfd] = old_fp; - bit_set(files->open_fds_init, newfd); - - if (flags & O_CLOEXEC) - bit_set(files->close_on_exec_init, newfd); - else - bit_clear(files->close_on_exec_init, newfd); - } - - if (existing) - fput(existing); - - return newfd; -} - -/* ================================================================== */ -/* do_close_on_exec — close all fds with CLOEXEC set */ -/* ================================================================== */ - -void do_close_on_exec(files_struct* files) -{ - for (int fd = 0; fd < files->max_fds; fd++) { - if (bit_test(files->close_on_exec_init, fd)) { - close_fd(files, fd); - } - } -} |