(Interim checkin while we work on this)

* devices.cc: Regenerate.
* devices.h (device::noexpose): New field.
(device::dev_on_fs): Make a bit field.
(get_major): Use proper type for declaration.
(expose): New field.
(ext_dev_storage): Delete declaration.
(dev_storage_size): Ditto.
(dev_storage): New declaration.
(dev_storage_end): Ditto.
* devices.in: Mark /dev/ptym*, /dev/com*, /dev/pipe, /dev/fifo, and "/dev" as
"no expose".
* fhandler.h (fhandler_dev::lastrealpos): Delete declaration.
(fhandler_dev::devidx): Declare new field.
* fhandler_disk_file.cc: Move fhandler_dev functions into fhandler_dev.cc.
* fhandler_dev.cc: Add includes needed for functions moved from
fhandler_disk_file.cc.
(dev_storage_scan_start): Define place to start listing devices.
(dev_storage_size): Define size of array to scan.
(fhandler_dev::fhandler_dev): Move here from fhandler_disk_file.cc.
(fhandler_dev::opendir): Ditto.
(fhandler_dev::readdir): Just check devidx for non-NULL to determine when to go
to disk for /dev content.  Use dev_storage rather than ext_dev_storage.
Iterate over dev_storage using devidx pointer.  Use accessor functions rather
than raw references to the device struct.  Only increment dir->__d_position
when we are actually going to be returning something.  Add debug_printf for
exit.
(fhandler_dev::rewinddir): Set devidx as appropriate depending on whether
there's a /dev on disk or not.
* gendevices: Don't mark dev_storage static but do put it in the _RDATA
section.
* path.cc (path_conv::check): Use new "device::expose()" function to decide to
forbid programs from referencing internal device types.

1 files changed, 178 insertions, 128 deletions

diff --git a/winsup/cygwin/fhandler_dev.cc b/winsup/cygwin/fhandler_dev.cc
index 27b1ef321..713e8c0fb 100644
--- a/winsup/cygwin/fhandler_dev.cc
+++ b/winsup/cygwin/fhandler_dev.cc
@@ -14,12 +14,16 @@ details. */
 #include "fhandler.h"
 #include "shared_info.h"
 #include "ntdll.h"
+#include "dtable.h"
+#include "cygheap.h"
 #include "devices.h"
 
 #define _COMPILING_NEWLIB
 #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)
@@ -28,13 +32,73 @@ device_cmp (const void *a, const void *b)
 		 ((const device *) b)->name + dev_prefix_len);
 }
 
+fhandler_dev::fhandler_dev () :
+  fhandler_disk_file (), devidx (NULL), dir_exists (true)
+{
+}
+
+DIR *
+fhandler_dev::opendir (int fd)
+{
+  DIR *dir;
+  DIR *res = NULL;
+
+  dir = fhandler_disk_file::opendir (fd);
+  if (dir)
+    return dir;
+  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
+	{
+	  cfd = this;
+	  dir->__d_fd = cfd;
+	  cfd->nohandle (true);
+	}
+      set_close_on_exec (true);
+      dir->__fh = this;
+      devidx = dev_storage_scan_start;
+      res = dir;
+    }
+
+  syscall_printf ("%p = opendir (%s)", res, get_name ());
+  return res;
+
+free_dirent:
+  free (dir->__d_dirent);
+free_dir:
+  free (dir);
+  return res;
+}
+
 int
 fhandler_dev::readdir (DIR *dir, dirent *de)
 {
   int ret;
   device dev;
 
-  if (dir_exists && !lastrealpos)
+  if (!devidx)
     {
       while ((ret = fhandler_disk_file::readdir (dir, de)) == 0)
 	{
@@ -42,153 +106,139 @@ fhandler_dev::readdir (DIR *dir, dirent *de)
 	     /dev already, for instance by using the old script from Igor
 	     Peshansky. */
 	  dev.name = de->d_name;
-	  if (!bsearch (&dev, ext_dev_storage, dev_storage_size, sizeof dev,
-		       device_cmp))
+	  if (!bsearch (&dev, dev_storage_scan_start, dev_storage_size, sizeof dev,
+			device_cmp))
 	    break;
 	}
       if (ret == ENMFILE)
-	lastrealpos = dir->__d_position;
+	devidx = dev_storage_scan_start;
+      else
+	goto out;
     }
-  if (!dir_exists || lastrealpos)
+
+  /* Now start processing our internal dev table. */
+  ret = ENMFILE;
+  while (devidx < dev_storage_end)
     {
-      ret = ENMFILE;
-      for (size_t idx = dir->__d_position - lastrealpos + 1;
-	   idx < dev_storage_size;
-	   ++idx)
+      const device& thisdev = *devidx++;
+      if (!thisdev.expose ())
+	continue;
+      int devn = *const_cast<device *> (&thisdev);
+      /* Exclude devices which are only available for internal purposes
+	 and devices which are not really existing at this time. */
+      switch (thisdev.get_major ())
 	{
-	  ++dir->__d_position;
-	  /* Exclude devices which are only available for internal purposes
-	     and devices which are not really existing at this time. */
-	  switch (ext_dev_storage[idx].d.major)
+	case DEV_PTYS_MAJOR:
+	  /* Show only existing slave ptys. */
+	  if (cygwin_shared->tty.connect (thisdev.get_minor ()) == -1)
+	    continue;
+	  break;
+	case DEV_CONS_MAJOR:
+	  /* Show only the one console which is our controlling tty
+	     right now. */
+	  if (!iscons_dev (myself->ctty)
+	      || myself->ctty != devn)
+	    continue;
+	  break;
+	case DEV_TTY_MAJOR:
+	  /* Show con{in,out,sole} only if we're running in a console. */
+	  switch (devn)
 	    {
-	    case DEV_VIRTFS_MAJOR:
-	      /* Drop /dev/fifo and /dev/pipe since they are internal only. */
-	      switch (ext_dev_storage[idx].d.devn)
-		{
-		case FH_FIFO:
-		case FH_PIPE:
-		  continue;
-		}
-	      break;
-	    case DEV_PTYM_MAJOR:
-	      /* Only /dev/ptmx is user-visible. */
-	      if (strcmp (ext_dev_storage[idx].name + dev_prefix_len, "ptmx"))
+	    case FH_CONIN:
+	    case FH_CONOUT:
+	    case FH_CONSOLE:
+	      if (!iscons_dev (myself->ctty))
 		continue;
-	      break;
-	    case DEV_PTYS_MAJOR:
-	      /* Show only existing slave ptys. */
-	      if (cygwin_shared->tty.connect (ext_dev_storage[idx].d.minor)
-		  == -1)
-		continue;
-	      break;
-	    case DEV_CONS_MAJOR:
-	      /* Show only the one console which is our controlling tty
-		 right now. */
-	      if (!iscons_dev (myself->ctty)
-		  || myself->ctty != ext_dev_storage[idx].d.devn_int)
-		continue;
-	      break;
-	    case DEV_TTY_MAJOR:
-	      /* Show con{in,out,sole} only if we're running in a console. */
-	      switch (ext_dev_storage[idx].d.devn)
-		{
-		case FH_CONIN:
-		case FH_CONOUT:
-		case FH_CONSOLE:
-		  if (!iscons_dev (myself->ctty))
-		    continue;
-		}
-	      break;
-	    case DEV_SERIAL_MAJOR:
-	      /* Ignore comX devices, only print ttySx. */
-	      if (ext_dev_storage[idx].name[dev_prefix_len] == 'c')
-		continue;
-	      /*FALLTHRU*/
-	    case DEV_FLOPPY_MAJOR:
-	    case DEV_TAPE_MAJOR:
-	    case DEV_CDROM_MAJOR:
-	    case DEV_SD_MAJOR:
-	    case DEV_SD1_MAJOR:
-	    case DEV_SD2_MAJOR:
-	    case DEV_SD3_MAJOR:
-	    case DEV_SD4_MAJOR:
-	    case DEV_SD5_MAJOR:
-	    case DEV_SD6_MAJOR:
-	    case DEV_SD7_MAJOR:
-	      /* Check existence of POSIX devices backed by real NT devices. */
+	    }
+	  break;
+	case DEV_SERIAL_MAJOR:
+	case DEV_FLOPPY_MAJOR:
+	case DEV_TAPE_MAJOR:
+	case DEV_CDROM_MAJOR:
+	case DEV_SD_MAJOR:
+	case DEV_SD1_MAJOR:
+	case DEV_SD2_MAJOR:
+	case DEV_SD3_MAJOR:
+	case DEV_SD4_MAJOR:
+	case DEV_SD5_MAJOR:
+	case DEV_SD6_MAJOR:
+	case DEV_SD7_MAJOR:
+	  /* Check existence of POSIX devices backed by real NT devices. */
+	  {
+	    WCHAR wpath[MAX_PATH];
+	    UNICODE_STRING upath;
+	    OBJECT_ATTRIBUTES attr;
+	    HANDLE h;
+	    NTSTATUS status;
+
+	    sys_mbstowcs (wpath, MAX_PATH, thisdev.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)
 	      {
-		WCHAR wpath[MAX_PATH];
-		UNICODE_STRING upath;
-		OBJECT_ATTRIBUTES attr;
-		HANDLE h;
-		NTSTATUS status;
-
-		sys_mbstowcs (wpath, MAX_PATH, ext_dev_storage[idx].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:
-		    continue;
-		  case STATUS_SUCCESS:
-		    NtClose (h);
-		    break;
-		  default:
-		    break;
-		  }
+	      case STATUS_OBJECT_NAME_NOT_FOUND:
+	      case STATUS_OBJECT_PATH_NOT_FOUND:
+		continue;
+	      case STATUS_SUCCESS:
+		NtClose (h);
+		break;
+	      default:
+		break;
 	      }
-	      break;
-	    }
-	  strcpy (de->d_name, ext_dev_storage[idx].name + dev_prefix_len);
-	  de->d_ino = hash_path_name (0, ext_dev_storage[idx].native);
-	  switch (ext_dev_storage[idx].d.major)
+	  }
+	  break;
+	}
+      ++dir->__d_position;
+      strcpy (de->d_name, thisdev.name + dev_prefix_len);
+      de->d_ino = hash_path_name (0, thisdev.native);
+      switch (thisdev.get_major ())
+	{
+	case DEV_FLOPPY_MAJOR:
+	case DEV_TAPE_MAJOR:
+	case DEV_CDROM_MAJOR:
+	case DEV_SD_MAJOR:
+	case DEV_SD1_MAJOR:
+	case DEV_SD2_MAJOR:
+	case DEV_SD3_MAJOR:
+	case DEV_SD4_MAJOR:
+	case DEV_SD5_MAJOR:
+	case DEV_SD6_MAJOR:
+	case DEV_SD7_MAJOR:
+	  de->d_type = DT_BLK;
+	  break;
+	case DEV_TTY_MAJOR:
+	  switch (devn)
 	    {
-	    case DEV_FLOPPY_MAJOR:
-	    case DEV_TAPE_MAJOR:
-	    case DEV_CDROM_MAJOR:
-	    case DEV_SD_MAJOR:
-	    case DEV_SD1_MAJOR:
-	    case DEV_SD2_MAJOR:
-	    case DEV_SD3_MAJOR:
-	    case DEV_SD4_MAJOR:
-	    case DEV_SD5_MAJOR:
-	    case DEV_SD6_MAJOR:
-	    case DEV_SD7_MAJOR:
-	      de->d_type = DT_BLK;
-	      break;
-	    case DEV_TTY_MAJOR:
-	      switch (ext_dev_storage[idx].d.devn)
-		{
-		  case FH_CONIN:
-		  case FH_CONOUT:
-		  case FH_CONSOLE:
-		    dev.parse (myself->ctty);
-		    de->d_ino = hash_path_name (0, dev.native);
-		    break;
-		}
-	      /*FALLTHRU*/
-	    default:
-	      de->d_type = DT_CHR;
+	    case FH_CONIN:
+	    case FH_CONOUT:
+	    case FH_CONSOLE:
+	      dev.parse (myself->ctty);
+	      de->d_ino = hash_path_name (0, dev.native);
 	      break;
 	    }
-	  ret = 0;
-	      break;
+	  /*FALLTHRU*/
+	default:
+	  de->d_type = DT_CHR;
+	  break;
 	}
+      ret = 0;
+      break;
     }
+
+out:
+  debug_printf ("returning %d", ret);
   return ret;
 }
 
 void
 fhandler_dev::rewinddir (DIR *dir)
 {
-  lastrealpos = 0;
+  devidx = dir_exists ? NULL : dev_storage_scan_start;
   fhandler_disk_file::rewinddir (dir);
 }
-