libc/winsup/cygwin/devices.in

%import {
#include "winsup.h"
#include "devices.h"
#include "sys/cygwin.h"
#include "tty.h"
#include "pinfo.h"
#include "shared_info.h"
#include "path.h"
#include "fhandler.h"
#include "ntdll.h"

typedef const _device *KR_device_t;
}
%type KR_device_t
%local {

static int
exists_internal (const device&)
{
  return false;
}

static int
exists (const device&)
{
  return true;
}

/* Check existence of POSIX devices backed by real NT devices. */
static int
exists_ntdev (const device& dev)
{
  WCHAR wpath[MAX_PATH];
  UNICODE_STRING upath;
  OBJECT_ATTRIBUTES attr;
  HANDLE h;
  NTSTATUS status;

  sys_mbstowcs (wpath, MAX_PATH, dev.native ());
  RtlInitUnicodeString (&upath, wpath);
  InitializeObjectAttributes (&attr, &upath, OBJ_CASE_INSENSITIVE, NULL, NULL);
  /* Except for the serial IO devices, the native paths are
     direct device paths, not symlinks, so every status code
     except for "NOT_FOUND" means the device exists. */
  status = NtOpenSymbolicLinkObject (&h, SYMBOLIC_LINK_QUERY, &attr);
  switch (status)
    {
    case STATUS_OBJECT_NAME_NOT_FOUND:
    case STATUS_OBJECT_PATH_NOT_FOUND:
      return false;
    case STATUS_SUCCESS:
      NtClose (h);
    default:
      break;
    }
  return true;
}

/* Don't list via readdir but allow as a direct reference. */
static int
exists_ntdev_silent (const device& dev)
{
  return exists_ntdev (dev) ? -1 : false;
}

static int
exists_console (const device& dev)
{
  fh_devices devn = *const_cast<device *> (&dev);
  switch (devn)
    {
    case FH_CONSOLE:
    case FH_CONIN:
    case FH_CONOUT:
      return fhandler_console::exists ();
    default:
      /* Only show my own console device (for now?) */
      return iscons_dev (myself->ctty) && myself->ctty == devn;
    }
}

static int
exists_pty (const device& dev)
{
  /* Only existing slave ptys. */
  return cygwin_shared->tty.connect (dev.get_minor ()) != -1;
}

const _device dev_cygdrive_storage =
  {"/cygdrive", {FH_CYGDRIVE}, "", exists};

const _device dev_fs_storage =
  {"", {FH_FS}, "", exists};

const _device dev_proc_storage =
  {"", {FH_PROC}, "", exists};

const _device dev_procnet_storage =
  {"", {FH_PROCNET}, "", exists};

const _device dev_procsys_storage =
  {"", {FH_PROCSYS}, "", exists};

const _device dev_procsysvipc_storage =
  {"", {FH_PROCSYSVIPC}, "", exists};

const _device dev_netdrive_storage =
  {"", {FH_NETDRIVE}, "", exists};

const _device dev_registry_storage =
  {"", {FH_REGISTRY}, "", exists_internal};

const _device dev_piper_storage =
  {"", {FH_PIPER}, "", exists_internal};

const _device dev_pipew_storage =
  {"", {FH_PIPEW}, "", exists_internal};

const _device dev_socket_storage =
  {"", {FH_SOCKET}, "", exists_internal};

const _device dev_af_inet_storage =
  {"", {FH_INET}, "", exists_internal};

const _device dev_af_unix_storage =
  {"", {FH_UNIX}, "", exists_internal};

const _device dev_af_local_storage =
  {"", {FH_LOCAL}, "", exists_internal};

const _device dev_bad_storage =
  {"", {FH_NADA}, "", exists_internal};

const _device dev_error_storage =
  {"", {FH_ERROR}, "", exists_internal};

#define BRACK(x) {devn: x}
%storage_here
}
/* Internal devices below are prefixed with a ":".  This moves them out of
   the POSIX namespace.  */
%%
"/dev", BRACK(FH_DEV), "", exists, S_IFDIR
"/dev/tty", BRACK(FH_TTY), "/dev/tty", exists, S_IFCHR
"/dev/pty%(0-127)d", BRACK(FHDEV(DEV_PTYS_MAJOR, {$1})), "/dev/pty{$1}", exists_pty, S_IFCHR, =ptys_dev
":ptym%(0-127)d", BRACK(FHDEV(DEV_PTYM_MAJOR, {$1})), "/dev/ptym{$1}", exists_internal, S_IFCHR, =ptym_dev
"/dev/cons%(0-127)d", BRACK(FHDEV(DEV_CONS_MAJOR, {$1})), "/dev/cons{$1}", exists_console, S_IFCHR, =cons_dev
"/dev/console", BRACK(FH_CONSOLE), "/dev/console", exists_console, S_IFCHR, =console_dev
"/dev/ptmx", BRACK(FH_PTMX), "/dev/ptmx", exists, S_IFCHR
"/dev/windows", BRACK(FH_WINDOWS), "\\Device\\Null", exists_ntdev, S_IFCHR
"/dev/dsp", BRACK(FH_OSS_DSP), "\\Device\\Null", exists_ntdev, S_IFCHR
"/dev/conin", BRACK(FH_CONIN), "/dev/conin", exists_console, S_IFCHR
"/dev/conout", BRACK(FH_CONOUT), "/dev/conout", exists_console, S_IFCHR
"/dev/null", BRACK(FH_NULL), "\\Device\\Null", exists_ntdev, S_IFCHR
"/dev/zero", BRACK(FH_ZERO), "\\Device\\Null", exists_ntdev, S_IFCHR
"/dev/full", BRACK(FH_FULL), "\\Device\\Null", exists_ntdev, S_IFCHR
"/dev/random", BRACK(FH_RANDOM), "\\Device\\Null", exists_ntdev, S_IFCHR
"/dev/urandom", BRACK(FH_URANDOM), "\\Device\\Null", exists_ntdev, S_IFCHR, =urandom_dev
"/dev/clipboard", BRACK(FH_CLIPBOARD), "\\Device\\Null", exists_ntdev, S_IFCHR
"/dev/com%(1-16)d", BRACK(FHDEV(DEV_SERIAL_MAJOR, {$1 - 1})), "\\??\\COM{$1}", exists_ntdev_silent, S_IFCHR
"/dev/ttyS%(0-63)d", BRACK(FHDEV(DEV_SERIAL_MAJOR, {$1})), "\\??\\COM{$1 + 1}", exists_ntdev, S_IFCHR
":pipe", BRACK(FH_PIPE), "/dev/pipe", exists_internal, S_IFCHR
":fifo", BRACK(FH_FIFO), "/dev/fifo", exists_internal, S_IFCHR
"/dev/st%(0-127)d", BRACK(FHDEV(DEV_TAPE_MAJOR, {$1})), "\\Device\\Tape{$1}", exists_ntdev, S_IFBLK
"/dev/nst%(0-127)d", BRACK(FHDEV(DEV_TAPE_MAJOR, {$1 + 128})), "\\Device\\Tape{$1}", exists_ntdev, S_IFBLK
"/dev/fd%(0-15)d", BRACK(FHDEV(DEV_FLOPPY_MAJOR, {$1})), "\\Device\\Floppy{$1}", exists_ntdev, S_IFBLK
"/dev/scd%(0-15)d", BRACK(FHDEV(DEV_CDROM_MAJOR, {$1})), "\\Device\\CdRom{$1}", exists_ntdev, S_IFBLK
"/dev/sr%(0-15)d", BRACK(FHDEV(DEV_CDROM_MAJOR, {$1})), "\\Device\\CdRom{$1}", exists_ntdev, S_IFBLK
%other	{return	NULL;}
%%
#undef BRACK

const _device *dev_storage_end = dev_storage
				+ (sizeof dev_storage / sizeof dev_storage[0]);

/* Convert disk/partition to major/minor */
static void
conv_dp_to_mm (int drive, int part, _major_t &major, _minor_t &minor)
{
  if (part >= 16)
    {
      major = DEV_SD_HIGHPART_START + drive / 5;
      drive %= 5;
      minor = (part - 16) + 48 * drive;
      return;
    }
  if (drive < ('q' - 'a'))      /* /dev/sda -to- /dev/sdp */
    major = DEV_SD_MAJOR;
  else if (drive < 32)		/* /dev/sdq -to- /dev/sdaf */
    {
      major = DEV_SD1_MAJOR;
      drive -= 'q' - 'a';
    }
  else if (drive < 48)		/* /dev/sdag -to- /dev/sdav */
    {
      major = DEV_SD2_MAJOR;
      drive -= 32;
    }
  else if (drive < 64)		/* /dev/sdaw -to- /dev/sdbl */
    {
      major = DEV_SD3_MAJOR;
      drive -= 48;
    }
  else if (drive < 80)		/* /dev/sdbm -to- /dev/sdcb */
    {
      major = DEV_SD4_MAJOR;
      drive -= 64;
    }
  else if (drive < 96)		/* /dev/sdcc -to- /dev/sdcr */
    {
      major = DEV_SD5_MAJOR;
      drive -= 80;
    }
  else if (drive < 112)		/* /dev/sdcs -to- /dev/sddh */
    {
      major = DEV_SD6_MAJOR;
      drive -= 96;
    }
  /* NOTE: This will cause multiple /dev/sddx entries in
	   /proc/partitions if there are more than 128 devices */
  else				/* /dev/sddi -to- /dev/sddx */
    {
      major = DEV_SD7_MAJOR;
      drive -= 112;
    }
  minor = part + (drive * 16);
}

#define DISK_PREFIX	"/dev/sd"
#define DP_LEN		(sizeof (DISK_PREFIX) - 1)

static const char *hd_pattern = "\\Device\\Harddisk%u\\Partition%u";

void
device::parse (const char *s)
{
  size_t len = strlen (s);
  const _device *dev = KR_find_keyword (s, len);

  if (!dev)
    {
      /* /dev/sd* devices have 8192 entries, given that we support 128 disks
	 with up to 64 partitions.  Handling them with shilka raises the size
	 of devices.o from ~250K to ~2 Megs.  So we handle them here manually
	 to save this space. */
      int drive = 0, part = 0;
      const char *pos = s + DP_LEN;

      /* Generic check for /dev/sd[a-z] prefix */
      if (len <= DP_LEN || strncmp (s, DISK_PREFIX, DP_LEN)
	  || pos[0] < 'a' || pos[0] > 'z')
	goto no_disk;

      /* /dev/sdd[a-x]? */
      if (pos[0] == 'd' && pos[1] >= 'a' && pos[1] <= 'x')
	{
	  drive = 104 + (pos[1] - 'a');
	  ++pos;
	}
      /* /dev/sd[a-c][a-z]? */
      else if (pos[0] <= 'c' && pos[1] >= 'a' && pos[1] <= 'z')
	{
	  drive = 26 + (pos[0] - 'a') * 26 + (pos[1] - 'a');
	  ++pos;
	}
      else
	drive = (pos[0] - 'a');
      /* Check next position in string for partition number. */
      ++pos;
      /* No partition number, equivalent to Windows partition 0. */
      if (!pos[0])
	;
      /* First digit must not be 0. */
      else if (pos[0] < '1' || pos[0] > '9')
	goto no_disk;
      else if (!pos[1])
	part = (pos[0] - '0');
      else if (pos[1] < '0' || pos[1] > '9' || pos[2] != '\0')
	goto no_disk;
      else
	{
	  part = (pos[0] - '0') * 10 + (pos[1] - '0');
	  if (part > 63)
	    goto no_disk;
	}
      char buf[sizeof *hd_pattern + 32];
      __small_sprintf (buf, hd_pattern, drive, part);
      native (buf, false);
      if (exists_ntdev (*this))
	{
	  name (s, true);
	  conv_dp_to_mm (drive, part, d.major, d.minor);
	  native (buf, true);
	  exists_func = exists_ntdev;
	  _mode = S_IFBLK;
	  lives_in_dev = dev_on_fs = false;
	  return;
	}
no_disk:
      *this = *fs_dev;
    }
  else
    *this = *dev;
}

void
device::init ()
{
  /* nothing to do... yet */
}

void
device::parse (_major_t major, _minor_t minor)
{
  dev_t devn = FHDEV (major, minor);

  d.devn = 0;

  for (const _device *devidx = dev_storage; devidx < dev_storage_end; devidx++)
    if (devidx->d.devn == devn)
      {
	*this = *devidx;
	break;
      }

  if (!*this)
    d.devn = FHDEV (major, minor);
}

void
device::parse (dev_t dev)
{
  parse (_major (dev), _minor (dev));
}

void
device::parsedisk (int drive, int part)
{
  char buf[sizeof ("/dev/sddx63")], *bp;

  conv_dp_to_mm (drive, part, d.major, d.minor);
  bp = stpcpy (buf, "/dev/sd");
  if (drive >= 26)
    {
      drive -= 26;
      *bp++ = drive / 26 + 'a';
      drive %= 26;
    }
  *bp++ = drive + 'a';
  if (part)
    {
      if (part >= 10)
	{
	  *bp++ = part / 10 + '0';
	  part %= 10;
	}
      *bp++ = part + '0';
    }
  *bp = '\0';
  name (buf, true);
}