diff options
Diffstat (limited to 'winsup/cygwin/fhandler/dev.cc')
| -rw-r--r-- | winsup/cygwin/fhandler/dev.cc | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/winsup/cygwin/fhandler/dev.cc b/winsup/cygwin/fhandler/dev.cc new file mode 100644 index 000000000..c6bda5654 --- /dev/null +++ b/winsup/cygwin/fhandler/dev.cc @@ -0,0 +1,275 @@ +/* fhandler_dev.cc, Implement /dev. + +This file is part of Cygwin. + +This software is a copyrighted work licensed under the terms of the +Cygwin license. Please consult the file "CYGWIN_LICENSE" for +details. */ + +#include "winsup.h" +#include <stdlib.h> +#include <sys/statvfs.h> +#include "path.h" +#include "fhandler.h" +#include "dtable.h" +#include "cygheap.h" +#include "devices.h" + +#define _LIBC +#include <dirent.h> + +#define dev_prefix_len (sizeof ("/dev")) +#define dev_storage_scan_start (dev_storage + 1) +#define dev_storage_size (dev_storage_end - dev_storage_scan_start) + +static int +device_cmp (const void *a, const void *b) +{ + return strcmp (((const device *) a)->name (), + ((const device *) b)->name () + dev_prefix_len); +} + +fhandler_dev::fhandler_dev () : + fhandler_disk_file (), devidx (NULL), dir_exists (true) +{ +} + +int +fhandler_dev::open (int flags, mode_t mode) +{ + if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) + { + set_errno (EEXIST); + return 0; + } + if (flags & O_WRONLY) + { + set_errno (EISDIR); + return 0; + } + /* Filter O_CREAT flag to avoid creating a file called /dev accidentally. */ + int ret = fhandler_disk_file::open (flags & ~O_CREAT, mode); + if (!ret) + { + /* Open a fake handle to \\Device\\Null */ + ret = open_null (flags); + dir_exists = false; + } + return ret; +} + +int +fhandler_dev::close () +{ + return fhandler_disk_file::close (); +} + +int +fhandler_dev::fstat (struct stat *st) +{ + /* If /dev really exists on disk, return correct disk information. */ + if (pc.fs_got_fs ()) + return fhandler_disk_file::fstat (st); + /* Otherwise fake virtual filesystem. */ + fhandler_base::fstat (st); + st->st_ino = 2; + st->st_mode = S_IFDIR | STD_RBITS | STD_XBITS; + st->st_nlink = 1; + return 0; +} + +int +fhandler_dev::fstatvfs (struct statvfs *sfs) +{ + int ret = -1, opened = 0; + HANDLE fh = get_handle (); + + if (!fh) + { + if (!open (O_RDONLY, 0)) + return -1; + opened = 1; + } + if (pc.fs_got_fs ()) + ret = fhandler_disk_file::fstatvfs (sfs); + else + { + /* Virtual file system. Just return an empty buffer with a few values + set to something useful similar to Linux. */ + memset (sfs, 0, sizeof (*sfs)); + sfs->f_bsize = sfs->f_frsize = 4096; + sfs->f_flag = ST_RDONLY; + sfs->f_namemax = NAME_MAX; + ret = 0; + } + if (opened) + close (); + return ret; +} + +int +fhandler_dev::rmdir () +{ + set_errno (ENOTEMPTY); + return -1; +} + +DIR * +fhandler_dev::opendir (int fd) +{ + DIR *dir = fhandler_disk_file::opendir (fd); + if (dir) + dir_exists = true; + else if ((dir = (DIR *) malloc (sizeof (DIR))) == NULL) + set_errno (ENOMEM); + else if ((dir->__d_dirent = + (struct dirent *) malloc (sizeof (struct dirent))) == NULL) + { + set_errno (ENOMEM); + goto free_dir; + } + else + { + cygheap_fdnew cfd; + if (cfd < 0 && fd < 0) + goto free_dirent; + + dir->__d_dirname = NULL; + dir->__d_dirent->__d_version = __DIRENT_VERSION; + dir->__d_cookie = __DIRENT_COOKIE; + dir->__handle = INVALID_HANDLE_VALUE; + dir->__d_position = 0; + dir->__flags = 0; + dir->__d_internal = 0; + + if (fd >= 0) + dir->__d_fd = fd; + else if (!open (O_RDONLY, 0)) + goto free_dirent; + else + { + cfd = this; + dir->__d_fd = cfd; + } + set_close_on_exec (true); + dir->__fh = this; + dir_exists = false; + drive = part = 0; + } + + devidx = dir_exists ? NULL : dev_storage_scan_start; + + syscall_printf ("%p = opendir (%s)", dir, get_name ()); + return dir; + +free_dirent: + free (dir->__d_dirent); +free_dir: + free (dir); + return NULL; +} + +static const WCHAR *hd_pattern = L"\\Device\\Harddisk%u\\Partition%u"; + +int +fhandler_dev::readdir (DIR *dir, dirent *de) +{ + int ret; + const _device *curdev; + device dev; + + if (!devidx) + { + while ((ret = fhandler_disk_file::readdir (dir, de)) == 0) + { + /* Avoid to print devices for which users have created files under + /dev already, for instance by using the old script from Igor + Peshansky. */ + dev.name (de->d_name); + if (!bsearch (&dev, dev_storage_scan_start, dev_storage_size, + sizeof dev, device_cmp)) + break; + } + if (ret != ENMFILE) + goto out; + devidx = dev_storage_scan_start; + } + + /* Now start processing our internal dev table. */ + ret = ENMFILE; + while ((curdev = devidx++) < dev_storage_end) + { + /* If exists returns < 0 it means that the device can be used by a + program but its use is deprecated and, so, it is not returned + by readdir((). */ + device *cdev = (device *) curdev; + if (cdev->exists () <= 0) + continue; + ++dir->__d_position; + strcpy (de->d_name, cdev->name () + dev_prefix_len); + if (cdev->get_major () == DEV_TTY_MAJOR + && (cdev->is_device (FH_CONIN) + || cdev->is_device (FH_CONOUT) + || cdev->is_device (FH_CONSOLE))) + { + /* Make sure conin, conout, and console have the same inode number + as the current consX. */ + de->d_ino = myself->ctty; + } + else + de->d_ino = cdev->get_device (); + de->d_type = cdev->type (); + ret = 0; + break; + } + /* Last but not least, scan for existing disks/partitions. */ + if (ret) + { + UNICODE_STRING upath; + WCHAR buf[(sizeof *hd_pattern + 32) / sizeof (wchar_t)]; + OBJECT_ATTRIBUTES attr; + FILE_BASIC_INFORMATION fbi; + NTSTATUS status; + + InitializeObjectAttributes (&attr, &upath, 0, NULL, NULL); + while (drive < 128) + { + while (part < 64) + { + USHORT len = __small_swprintf (buf, hd_pattern, drive, part); + RtlInitCountedUnicodeString (&upath, buf, len * sizeof (WCHAR)); + status = NtQueryAttributesFile (&attr, &fbi); + debug_printf ("%S %y", &upath, status); + if (status != STATUS_OBJECT_NAME_NOT_FOUND + && status != STATUS_OBJECT_PATH_NOT_FOUND) + { + device dev (drive, part); + strcpy (de->d_name, dev.name () + 5); + de->d_ino = dev.get_device (); + de->d_type = DT_BLK; + ++part; + ret = 0; + goto out; + } + if (part == 0) + break; + ++part; + } + part = 0; + ++drive; + } + } + +out: + debug_printf ("returning %d", ret); + return ret; +} + +void +fhandler_dev::rewinddir (DIR *dir) +{ + devidx = dir_exists ? NULL : dev_storage_scan_start; + dir->__d_position = 0; + if (dir_exists) + fhandler_disk_file::rewinddir (dir); +} |