glibc/sysdeps/mach/hurd/dl-sysdep.c

/* Operating system support for run-time dynamic linker.  Hurd version.
Copyright (C) 1995 Free Software Foundation, Inc.
This file is part of the GNU C Library.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.

The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include <hurd.h>
#include <link.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <sys/wait.h>
#include <assert.h>
#include <sysdep.h>
#include <mach/mig_support.h>
#include "hurdstartup.h"
#include <mach/host_info.h>
#include "../stdio/_itoa.h"
#include <hurd/auth.h>
#include <hurd/term.h>
#include <stdarg.h>

#include "dl-machine.h"

extern void __mach_init (void);

extern int _dl_argc;
extern char **_dl_argv;
extern char **_environ;

struct hurd_startup_data *_dl_hurd_data;

Elf32_Addr
_dl_sysdep_start (void **start_argptr,
		  void (*dl_main) (const Elf32_Phdr *phdr, Elf32_Word phent,
				   Elf32_Addr *user_entry))
{
  void go (int *argdata)
    {
      char **p;

      /* Cache the information in various global variables.  */
      _dl_argc = *argdata;
      _dl_argv = (void *) &argdata[1];
      _environ = &_dl_argv[_dl_argc + 1];
      for (p = _environ; *p; ++p);
      _dl_hurd_data = (void *) ++p;

      _dl_secure = _dl_hurd_data->flags & EXEC_SECURE;

      /* Call elf/rtld.c's main program.  It will set everything
	 up and leave us to transfer control to USER_ENTRY.  */
      (*dl_main) ((const Elf32_Phdr *) _dl_hurd_data->phdr,
		  _dl_hurd_data->phdrsz / sizeof (Elf32_Phdr),
		  &_dl_hurd_data->user_entry);

      /* Deallocate the reply port and task port rights acquired by
	 __mach_init.  We are done with them now, and the user will
	 reacquire them for himself when he wants them.  */
      __mig_dealloc_reply_port (MACH_PORT_NULL);
      __mach_port_deallocate (__mach_task_self (), __mach_task_self_);

      {
	extern void _dl_start_user (void);
	/* Unwind the stack to ARGDATA and simulate a return from _dl_start
	   to the RTLD_START code which will run the user's entry point.  */
	RETURN_TO (argdata, &_dl_start_user, _dl_hurd_data->user_entry);
      }
    }

  /* Set up so we can do RPCs.  */
  __mach_init ();

  /* See hurd/hurdstartup.c; this deals with getting information
     from the exec server and slicing up the arguments.
     Then it will call `go', above.  */
  _hurd_startup (start_argptr, &go);

  LOSE;
}

/* This is called when all other dynamic linking is finished, before the
   dynamic linker re-relocates itself when ld.so itself appears in a
   DT_NEEDED entry.  It is called whether of not ld.so is being linked in.

   We take this opportunity to deallocate the reply port and task-self send
   right user reference we have acquired, since they will not be used again
   before the library and user code runs.  The C library will acquire its
   own ports in its initialization.  */

void
_dl_sysdep_prepare_for_ld_reloc (void)
{
  __mig_dealloc_reply_port (__mig_get_reply_port ());
  __mach_port_deallocate (__mach_task_self (), __mach_task_self ());
}

int
_dl_sysdep_open_zero_fill (void)
{
  return (int) MACH_PORT_NULL;
}


void
_dl_sysdep_fatal (const char *msg, ...)
{
  extern __typeof (__io_write) __hurd_intr_rpc_io_write;
  va_list ap;

  va_start (ap, msg);
  do
    {
      size_t len = strlen (msg);
      mach_msg_type_number_t nwrote;
      do
	{
	  if (__hurd_intr_rpc_io_write (_hurd_init_dtable[2],
					msg, len, -1, &nwrote))
	    break;
	  len -= nwrote;
	  msg += nwrote;
	} while (nwrote > 0);
      msg = va_arg (ap, const char *);
    } while (msg);
  va_end (ap);

  _exit (127);
}


/* Minimal open/close/mmap implementation sufficient for initial loading of
   shared libraries.  These are weak definitions so that when the
   dynamic linker re-relocates itself to be user-visible (for -ldl),
   it will get the user's definition (i.e. usually libc's).  */

int
open (const char *file_name, int mode, ...)
{
  extern __typeof (__dir_lookup) __hurd_intr_rpc_dir_lookup;
  extern __typeof (__io_reauthenticate) __hurd_intr_rpc_io_reauthenticate;
  enum retry_type doretry;
  char retryname[1024];		/* XXX string_t LOSES! */
  file_t startdir, newpt, fileport;
  int dealloc_dir;
  int nloops;


  assert (mode == O_RDONLY);


  startdir = _dl_hurd_data->portarray[file_name[0] == '/' ?
				      INIT_PORT_CRDIR : INIT_PORT_CWDIR];

  while (file_name[0] == '/')
    file_name++;

  if (errno = __hurd_intr_rpc_dir_lookup (startdir, file_name, mode, 0,
					  &doretry, retryname, &fileport))
    return -1;

  dealloc_dir = 0;
  nloops = 0;
  errno = 0;
  
  while (1)
    {
      if (dealloc_dir)
	__mach_port_deallocate (__mach_task_self (), startdir);
      if (errno)
	return -1;

      switch (doretry)
	{
	case FS_RETRY_REAUTH:
	  {
	    mach_port_t ref = __mach_reply_port ();
	    errno = __hurd_intr_rpc_io_reauthenticate
	      (fileport, ref, MACH_MSG_TYPE_MAKE_SEND);
	    if (! errno)
	      errno = __auth_user_authenticate
		(_dl_hurd_data->portarray[INIT_PORT_AUTH],
		 fileport,
		 ref, MACH_MSG_TYPE_MAKE_SEND,
		 &newpt);
	    __mach_port_destroy (__mach_task_self (), ref);
	  }
	  __mach_port_deallocate (__mach_task_self (), fileport);
	  if (errno)
	    return -1;
	  fileport = newpt;
	  /* Fall through.  */

	case FS_RETRY_NORMAL:
#ifdef SYMLOOP_MAX
	  if (nloops++ >= SYMLOOP_MAX)
	    {
	      errno = ELOOP;
	      return -1;
	    }
#endif

	  /* An empty RETRYNAME indicates we have the final port.  */
	  if (retryname[0] == '\0')
	    {
	      mach_port_t memobj_rd, memobj_wr;
	      extern __typeof (__io_map) __hurd_intr_rpc_io_map;

	      dealloc_dir = 1;

	    opened:
	      /* We have the file open.  Now map it.  */
	      errno = __hurd_intr_rpc_io_map (fileport,
					      &memobj_rd, &memobj_wr);
	      if (dealloc_dir)
		__mach_port_deallocate (__mach_task_self (), fileport);
	      if (errno)
		return -1;
	      if (memobj_wr != MACH_PORT_NULL)
		__mach_port_deallocate (__mach_task_self (), memobj_wr);

	      return (int) memobj_rd;
	    }

	  startdir = fileport;
	  dealloc_dir = 1;
	  file_name = retryname;
	  break;

	case FS_RETRY_MAGICAL:
	  switch (retryname[0])
	    {
	    case '/':
	      startdir = _dl_hurd_data->portarray[INIT_PORT_CRDIR];
	      dealloc_dir = 0;
	      if (fileport != MACH_PORT_NULL)
		__mach_port_deallocate (__mach_task_self (), fileport);
	      file_name = &retryname[1];
	      break;

	    case 'f':
	      if (retryname[1] == 'd' && retryname[2] == '/')
		{
		  int fd;
		  char *end;
		  errno = 0;
		  fd = (int) strtol (retryname, &end, 10);
		  if (end == NULL || errno || /* Malformed number.  */
		      /* Check for excess text after the number.  A slash
			 is valid; it ends the component.  Anything else
			 does not name a numeric file descriptor.  */
		      (*end != '/' && *end != '\0'))
		    {
		      errno = ENOENT;
		      return -1;
		    }
		  if (fd < 0 || fd >= _dl_hurd_data->dtablesize ||
		      _dl_hurd_data->dtable[fd] == MACH_PORT_NULL)
		    {
		      /* If the name was a proper number, but the file
			 descriptor does not exist, we return EBADF instead
			 of ENOENT.  */
		      errno = EBADF;
		      return -1;
		    }
		  fileport = _dl_hurd_data->dtable[fd];
		  if (*end == '\0')
		    {
		      /* This descriptor is the file port we want.  */
		      dealloc_dir = 0;
		      goto opened;
		    }
		  else
		    {
		      /* Do a normal retry on the remaining components.  */
		      startdir = fileport;
		      dealloc_dir = 1;
		      file_name = end + 1; /* Skip the slash.  */
		      break;
		    }
		}
	      else
		goto bad_magic;
	      break;

	    case 'm':
	      if (retryname[1] == 'a' && retryname[2] == 'c' &&
		  retryname[3] == 'h' && retryname[4] == 't' &&
		  retryname[5] == 'y' && retryname[6] == 'p' &&
		  retryname[7] == 'e')
		{
		  error_t err;
		  struct host_basic_info hostinfo;
		  mach_msg_type_number_t hostinfocnt = HOST_BASIC_INFO_COUNT;
		  char *p;
		  if (err = __host_info (__mach_host_self (), HOST_BASIC_INFO,
					 (natural_t *) &hostinfo,
					 &hostinfocnt))
		    return err;
		  if (hostinfocnt != HOST_BASIC_INFO_COUNT)
		    return EGRATUITOUS;
		  p = _itoa (hostinfo.cpu_subtype, &retryname[8], 10, 0);
		  *--p = '/';
		  p = _itoa (hostinfo.cpu_type, &retryname[8], 10, 0);
		  if (p < retryname)
		    abort ();	/* XXX write this right if this ever happens */
		  if (p > retryname)
		    strcpy (retryname, p);
		  startdir = fileport;
		  dealloc_dir = 1;
		}
	      else
		goto bad_magic;
	      break;

	    case 't':
	      if (retryname[1] == 't' && retryname[2] == 'y')
		switch (retryname[3])
		  {
		    error_t opentty (file_t *result)
		      {
			error_t err;
			file_t unauth;
			err = __termctty_open_terminal
			  (_dl_hurd_data->portarray[INIT_PORT_CTTYID],
			   mode, &unauth);
			if (! err)
			  {
			    mach_port_t ref = __mach_reply_port ();
			    err = __hurd_intr_rpc_io_reauthenticate
			      (unauth, ref, MACH_MSG_TYPE_MAKE_SEND);
			    if (! err)
			      err = __auth_user_authenticate
				(_dl_hurd_data->portarray[INIT_PORT_AUTH],
				 unauth,
				 ref, MACH_MSG_TYPE_MAKE_SEND,
				 result);
			    __mach_port_deallocate (__mach_task_self (),
						    unauth);
			    __mach_port_destroy (__mach_task_self (), ref);
			  }
			return err;
		      }

		  case '\0':
		    if (errno = opentty (&fileport))
		      return -1;
		    dealloc_dir = 1;
		    goto opened;
		  case '/':
		    if (errno = opentty (&startdir))
		      return -1;
		    dealloc_dir = 1;
		    strcpy (retryname, &retryname[4]);
		    break;
		  default:
		    goto bad_magic;
		  }
	      else
		goto bad_magic;
	      break;

	    default:
	    bad_magic:
	      errno = EGRATUITOUS;
	      return -1;
	    }
	  break;		

	default:
	  errno = EGRATUITOUS;
	  return -1;
	}

      errno = __hurd_intr_rpc_dir_lookup (startdir, file_name, mode, 0,
					  &doretry, retryname, &fileport);
    }
}

int
close (int fd)
{
  if (fd != (int) MACH_PORT_NULL)
    __mach_port_deallocate (__mach_task_self (), (mach_port_t) fd);
  return 0;
}

caddr_t
mmap (caddr_t addr, size_t len, int prot, int flags, int fd, off_t offset)
{
  vm_prot_t vmprot;
  vm_address_t mapaddr;

  vmprot = VM_PROT_NONE;
  if (prot & PROT_READ)
    vmprot |= VM_PROT_READ;
  if (prot & PROT_WRITE)
    vmprot |= VM_PROT_WRITE;
  if (prot & PROT_EXEC)
    vmprot |= VM_PROT_EXECUTE;

  mapaddr = (vm_address_t) addr;
  errno = __vm_map (__mach_task_self (),
		    &mapaddr, (vm_size_t) len, (vm_address_t) 0,
		    !(flags & MAP_FIXED),
		    (mach_port_t) fd, (vm_offset_t) offset,
		    flags & (MAP_COPY|MAP_PRIVATE),
		    vmprot, VM_PROT_ALL,
		    (flags & MAP_INHERIT) ? VM_INHERIT_COPY : VM_INHERIT_NONE);
  return errno ? (caddr_t) -1 : (caddr_t) mapaddr;
}

void
_exit (int status)
{
  extern __typeof (__proc_mark_exit) __hurd_intr_rpc_proc_mark_exit;
  __hurd_intr_rpc_proc_mark_exit (_dl_hurd_data->portarray[INIT_PORT_PROC],
				  W_EXITCODE (status, 0));
  while (__task_terminate (__mach_task_self ()))
    __mach_task_self_ = (__mach_task_self) ();
}

weak_symbol (_exit)
weak_symbol (open)
weak_symbol (close)
weak_symbol (mmap)

/* Minimal `malloc' allocator for use while loading shared libraries.
   Only small blocks are allocated, and none are ever freed.  */

void *
malloc (size_t n)
{
  static vm_address_t ptr, end;
  void *block;

  if (end == 0)
    {
      /* Consume any unused space in the last page of our data segment.  */
      extern char _end;
      ptr = (vm_address_t) &_end;
      end = round_page (ptr);
    }

  /* Make sure the allocation pointer is ideally aligned.  */
  ptr += sizeof (double) - 1;
  ptr &= ~(sizeof (double) - 1);

  if (ptr + n >= end)
    {
      /* Insufficient space left; allocate another page.  */
      vm_address_t page;
      assert (n <= __vm_page_size);
      __vm_allocate (__mach_task_self (), &page, __vm_page_size, 1);
      if (page != end)
	ptr = page;
      end = page + __vm_page_size;
    }

  block = (void *) ptr;
  ptr += n;
  return block;
}

weak_symbol (malloc)

/* These should never be called.  */
void *realloc (void *ptr, size_t n) { ptr += n; abort (); }
void free (void *ptr) { ptr = ptr; abort (); }
weak_symbol (realloc)
weak_symbol (free)

/* Avoid signal frobnication in setjmp/longjmp.  */

int __sigjmp_save (sigjmp_buf env, int savemask) 
{ env[0].__mask_was_saved = savemask; return 0; }
weak_symbol (__sigjmp_save)

void
longjmp (jmp_buf env, int val) { __longjmp (env[0].__jmpbuf, val); }
weak_symbol (longjmp)


/* Stub out this function that is called by interruptible RPC stubs.  It
   should never get called during initial dynamic linking, because we use
   only the raw MiG stub functions __hurd_intr_rpc_*.  Since this defn is
   weak, the real defn in libc.so will override it if we are linked into
   the user program (-ldl).  */
struct hurd_sigstate *
_hurd_thread_sigstate (thread_t thread) { thread = thread; abort (); }
weak_symbol (_hurd_thread_sigstate)