banan-os/libc/dirent.cpp

93 lines
1.5 KiB
C++

#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <kernel/API/DirectoryEntry.h>
struct __DIR
{
int fd { -1 };
size_t entry_index { 0 };
Kernel::API::DirectoryEntry* current { nullptr };
size_t buffer_size { 0 };
Kernel::API::DirectoryEntryList buffer[];
};
int closedir(DIR* dirp)
{
if (dirp == nullptr || dirp->fd == -1)
{
errno = EBADF;
return -1;
}
close(dirp->fd);
dirp->fd = -1;
free(dirp);
return 0;
}
int dirfd(DIR* dirp)
{
if (dirp == nullptr || dirp->fd == -1)
{
errno = EINVAL;
return -1;
}
return dirp->fd;
}
DIR* fdopendir(int fd)
{
DIR* dirp = (DIR*)malloc(sizeof(DIR) + 4096);
if (dirp == nullptr)
return nullptr;
dirp->fd = fd;
dirp->current = nullptr;
dirp->buffer_size = 4096;
return dirp;
}
DIR* opendir(const char* dirname)
{
int fd = open(dirname, O_SEARCH);
if (fd == -1)
return nullptr;
return fdopendir(fd);
}
struct dirent* readdir(DIR* dirp)
{
if (dirp == nullptr || dirp->fd == -1)
{
errno = EBADF;
return nullptr;
}
dirp->entry_index++;
if (dirp->current && dirp->entry_index < dirp->buffer->entry_count)
{
dirp->current = dirp->current->next();
return &dirp->current->dirent;
}
if (syscall(SYS_READ_DIR_ENTRIES, dirp->fd, dirp->buffer, dirp->buffer_size) == -1)
return nullptr;
if (dirp->buffer->entry_count == 0)
return nullptr;
dirp->entry_index = 0;
dirp->current = dirp->buffer->array;
return &dirp->current->dirent;
}