Subject: Emacs-19.24 for NetBSD/sparc
To: None <current-users@sun-lamp.cs.berkeley.edu>
From: A.M. Raportirenko <ram@sunct1.jinr.dubna.su>
List: current-users
Date: 06/06/1994 20:42:59
Hi!

To complie emacs-19.24 on the NetBSD/sparc I used the following patches.
(I have also patches to emacs-19.25 but it is not works on the NetBSD now.)

I compiled it with the following script:

echo ../emacs-19.24/configure sparc-sun-netbsd --with-x11 --with-x-toolkit --x-includes=/usr/X11R5/include --x-libraries=/usr/X11R5/lib --srcdir=../emacs-19.24
../emacs-19.24/configure sparc-sun-netbsd --with-x11 --with-x-toolkit --x-includes=/usr/X11R5/include --x-libraries=/usr/X11R5/lib --srcdir=../emacs-19.24
echo make CFLAGS=-O
make CFLAGS=-O
#su
#make install

ram

diff -rc2N emacs-19.24.gnu/config.guess emacs-19.24.net/config.guess
*** emacs-19.24.gnu/config.guess	Sat Jun  4 15:00:56 1994
--- emacs-19.24.net/config.guess	Sat Jun  4 15:09:52 1994
***************
*** 194,197 ****
--- 194,200 ----
  	echo ${UNAME_MACHINE}-unknown-netbsd${UNAME_RELEASE}
  	exit 0 ;;
+     sparc:NetBSD:*:*)
+         echo ${UNAME_MACHINE}-sun-netbsd${UNAME_RELEASE}
+         exit 0 ;;
      i[34]86:Linux:*:*)
  	echo ${UNAME_MACHINE}-unknown-linux
diff -rc2N emacs-19.24.gnu/config.sub emacs-19.24.net/config.sub
*** emacs-19.24.gnu/config.sub	Sat Jun  4 15:00:56 1994
--- emacs-19.24.net/config.sub	Sat Jun  4 15:13:58 1994
***************
*** 295,298 ****
--- 295,302 ----
  		os=-solaris2
  		;;
+ 	i386-netbsd)
+ 		basic_machine=i386-unknown
+ 		os=-netbsd
+ 		;;
  	iris | iris4d)
  		basic_machine=mips-sgi
***************
*** 427,430 ****
--- 431,438 ----
  		basic_machine=sparc-sun
  		os=-sunos4
+ 		;;
+ 	sun4-netbsd)
+ 		basic_machine=sparc-sun
+ 		os=-netbsd
  		;;
  	sun3)
diff -rc2N emacs-19.24.gnu/configure emacs-19.24.net/configure
*** emacs-19.24.gnu/configure	Sat Jun  4 15:00:58 1994
--- emacs-19.24.net/configure	Sat Jun  4 15:15:56 1994
***************
*** 917,921 ****
  
    ## Suns
!   *-sun-sunos* | *-sun-bsd* | *-sun-solaris* )
      case "${canonical}" in
        m68*-sunos1* )	machine=sun1 ;;
--- 917,921 ----
  
    ## Suns
!   *-sun-sunos* | *-sun-bsd* | *-sun-solaris* | *-sun-netbsd* )
      case "${canonical}" in
        m68*-sunos1* )	machine=sun1 ;;
***************
*** 944,947 ****
--- 944,948 ----
  		NON_GNU_CPP=/usr/ccs/lib/cpp
  		;;
+       *-netbsd*		  ) opsys=netbsd ;;
        *			  ) opsys=bsd4-2   ;;
      esac
diff -rc2N emacs-19.24.gnu/configure.in emacs-19.24.net/configure.in
*** emacs-19.24.gnu/configure.in	Sat Jun  4 15:00:58 1994
--- emacs-19.24.net/configure.in	Sat Jun  4 15:17:58 1994
***************
*** 925,929 ****
  
    ## Suns
!   *-sun-sunos* | *-sun-bsd* | *-sun-solaris* )
      case "${canonical}" in
        m68*-sunos1* )	machine=sun1 ;;
--- 925,929 ----
  
    ## Suns
!   *-sun-sunos* | *-sun-bsd* | *-sun-solaris* | *-sun-netbsd* )
      case "${canonical}" in
        m68*-sunos1* )	machine=sun1 ;;
***************
*** 952,955 ****
--- 952,956 ----
  		NON_GNU_CPP=/usr/ccs/lib/cpp
  		;;
+       *-netbsd*		  ) opsys=netbsd ;;
        *			  ) opsys=bsd4-2   ;;
      esac
diff -rc2N emacs-19.24.gnu/src/m/sparc.h emacs-19.24.net/src/m/sparc.h
*** emacs-19.24.gnu/src/m/sparc.h	Sat Jun  4 15:01:18 1994
--- emacs-19.24.net/src/m/sparc.h	Sat Jun  4 15:07:29 1994
***************
*** 36,42 ****
--- 36,44 ----
  #define LONGBITS 32		/* Number of bits in a long */
  
+ #ifndef __NetBSD__
  /* SPARC has lowest-numbered byte as most significant */
  
  #define BIG_ENDIAN
+ #endif
  
  /* Define NO_ARG_ARRAY if you cannot take the address of the first of a
***************
*** 95,99 ****
--- 97,105 ----
  /* Mask for address bits within a memory segment */
  
+ #ifndef __NetBSD__
  #define SEGMENT_MASK (SEGSIZ - 1)
+ #else
+ #define SEGMENT_MASK (__LDPGSZ - 1)
+ #endif
  
  /* Arrange to link with sun windows, if requested.  */
***************
*** 109,112 ****
--- 115,119 ----
  #endif
  
+ #ifndef __NetBSD__
  /* Say that the text segment of a.out includes the header;
     the header actually occupies the first few bytes of the text segment
***************
*** 118,119 ****
--- 125,127 ----
  
  #define A_TEXT_SEEK(HDR) (N_TXTOFF (hdr) + sizeof (hdr))
+ #endif
diff -rc2N emacs-19.24.gnu/src/s/netbsd.h emacs-19.24.net/src/s/netbsd.h
*** emacs-19.24.gnu/src/s/netbsd.h	Sat Jun  4 15:01:29 1994
--- emacs-19.24.net/src/s/netbsd.h	Sat Jun  4 15:07:35 1994
***************
*** 46,51 ****
  #define HAVE_TEXT_START		/* No need to define `start_of_text'.  */
  #define START_FILES pre-crt0.o /usr/lib/crt0.o
! #define UNEXEC unexsunos4.o
  #define RUN_TIME_REMAP
  
  /* Try to make this work for both 0.9 and >0.9.  */
--- 46,52 ----
  #define HAVE_TEXT_START		/* No need to define `start_of_text'.  */
  #define START_FILES pre-crt0.o /usr/lib/crt0.o
! #define UNEXEC unexnetbsd.o
  #define RUN_TIME_REMAP
+ #define LINKER $(CC) -nostdlib -static
  
  /* Try to make this work for both 0.9 and >0.9.  */
diff -rc2N emacs-19.24.gnu/src/unexnetbsd.c emacs-19.24.net/src/unexnetbsd.c
*** emacs-19.24.gnu/src/unexnetbsd.c	Thu Jan  1 03:00:00 1970
--- emacs-19.24.net/src/unexnetbsd.c	Sat Jun  4 15:07:14 1994
***************
*** 0 ****
--- 1,709 ----
+ /* Code to do an unexec for FreeBSD-1.1 for a temacs linked -Bdynamic.
+    Derived from unexnetbsd.c, which was derived from unexsunos4.c
+    Copyright (C) 1992, 1993 Free Software Foundation, Inc.
+ 
+ This file is part of GNU Emacs.
+ 
+ GNU Emacs is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+ 
+ GNU Emacs 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 General Public License for more details.
+ 
+ You should have received a copy of the GNU General Public License
+ along with GNU Emacs; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ 
+ Created 29-Oct-92 by Harlan Sexton
+ Tweaked 06-Aug-93 by Dean Michaels to work with sun3.
+ Converted 01-Dec-93 by Paul Mackerras to work with NetBSD shared libraries.
+ Tweaked 26-Feb-94 by Shawn Carey for use with FreeBSD-1.1 shared libraries.
+ */
+ 
+ /********************** Included .h Files **************************/
+ 
+ #include <stdarg.h>
+ #include <sys/param.h>
+ #include <sys/mman.h>
+ #include <sys/file.h>
+ #include <sys/stat.h>
+ #include <sys/types.h>
+ #include <string.h>
+ #include <stdio.h>
+ #include <a.out.h>
+ #include <unistd.h>
+ #include <ctype.h>
+ #include <stab.h>
+ #include <sys/dir.h>
+ #include <link.h>
+ 
+ /********************** Macros *************************************/
+ 
+ #define SYS_ERR		strerror(errno)
+ 
+ #define MASK_UP(x,p_of_two) \
+  ((((unsigned long) (x)) + ((p_of_two) - 1)) & (~((p_of_two) - 1)))
+ 
+ #define MASK_DOWN(x,p_of_two) (((unsigned long) (x)) & (~((p_of_two) - 1)))
+ 
+ /********************** Typedefs and Structs ***********************/
+ 
+ struct translation_struct
+ {
+   long txtaddr;
+   long txtoff;
+   long dataddr;
+   long datoff;
+   long bssaddr;
+   long endaddr;
+ };
+ 
+ /********************** Function Prototypes/Declarations ***********/
+ 
+ static void unexec_error (const char *m, int use_errno, ...);
+ static int unexec_open (char *filename, int flag, int mode);
+ static caddr_t unexec_mmap (int fd, size_t len, int prot, int flags);
+ static long unexec_seek (int fd, long position);
+ static void unexec_read (int fd, long position, char *buf, int bytes);
+ static void unexec_write (int fd, long position, char *buf, int bytes);
+ static void unexec_pad (int fd, int bytes);
+ static void unexec_fstat (int fd, struct stat *statptr);
+ static void unexec_fchmod (int fd, int mode);
+ static long unexec_addr_to_offset (long addr, struct translation_struct *ts);
+ static void copy_relocation_site (struct relocation_info *ri, 
+                                   caddr_t from_base_addr, 
+                                   caddr_t to_base_addr, 
+                                   struct translation_struct *ts);
+ static void reset_symtab (struct nlist *start, struct nlist *end, 
+                           char *strtab, long edata_value, long end_value,
+                           int shlib_image);
+ static void reset_ldso_symtab (struct nzlist *start, struct nzlist *end, 
+                           char *strtab, long edata_value, long end_value,
+                           int shlib_image);
+ int run_time_remap (char *dummy);
+ 
+ /********************** Variables **********************************/
+ 
+ /* for reporting error messages from system calls */
+ extern int errno;
+ extern int _DYNAMIC;
+ extern char **environ;             
+ 
+ static unsigned long sbrk_of_0_at_unexec;
+              
+ /*******************************************************************/
+ 
+ static void
+ unexec_error (const char *fmt, int use_errno, ...)
+ {
+   const char *err_msg = SYS_ERR;
+   va_list args;
+ 
+   fprintf (stderr, "unexec - ");
+   va_start (args, use_errno);
+   vfprintf (stderr, fmt, args);
+   va_end (args);
+ 
+   if (use_errno)
+     fprintf (stderr, ": %s", err_msg);
+   fprintf (stderr, "\n");
+   exit (1);
+   return;
+ }
+ 
+ static int
+ unexec_open (char *filename, int flag, int mode)
+ {
+   int fd;
+ 
+   errno = 0;
+ 
+   fd = open (filename, flag, mode);
+ 
+   if (fd < 0)
+     unexec_error ("Failure opening file %s", 1, filename);
+   return fd;
+ }
+ 
+ static caddr_t
+ unexec_mmap (int fd, size_t len, int prot, int flags)
+ {
+   caddr_t return_val;
+ 
+   unexec_seek (fd, 0);
+   errno = 0;
+   return_val = mmap (0, len, prot, flags, fd, 0);
+ 
+   if (return_val == (caddr_t) -1)
+     unexec_error ("Failure mmap'ing file", 1);
+   return return_val;
+ }
+ 
+ 
+ static long
+ unexec_seek (int fd, long position)
+ {
+   long seek_value;
+ 
+   if (fd <= 0)
+     unexec_error ("No file open in which to seek", 0);
+ 
+   errno = 0;
+ 
+   if (position < 0)
+     seek_value = (long) lseek (fd, 0, L_INCR);
+   else
+     seek_value = (long) lseek (fd, position, L_SET);
+ 
+   if (seek_value < 0)
+     unexec_error ("Failed to do a seek to 0x%x in %s", 1,
+                   position, "unexec() output file");
+ 
+   return seek_value;
+ }
+ 
+ static void
+ unexec_read (int fd, long position, char *buf, int bytes)
+ {
+   int n_read;
+   int remains = bytes;
+   position = unexec_seek (fd, position);
+ 
+   if (bytes < 0)
+     unexec_error ("Attempted read of %d bytes", 0, bytes);
+ 
+   errno = 0;
+ 
+   while (remains > 0)
+     {
+       n_read = read (fd, buf, remains);
+       if (n_read <= 0)
+         unexec_error ("Read failed for 0x%x bytes at offset 0x%x in %s",
+                       1, bytes, position, "unexec() output file");
+       buf += n_read;
+       remains -= n_read;
+     }
+ 
+   return;
+ }
+ 
+ static void
+ unexec_write (int fd, long position, char *buf, int bytes)
+ {
+   int n_written;
+   int remains = bytes;
+   position = unexec_seek (fd, position);
+ 
+   if (bytes < 0)
+     unexec_error ("Attempted write of %d bytes in %s",
+                   0, bytes, "unexec() output file");
+ 
+   errno = 0;
+ 
+   while (remains > 0)
+     {
+       n_written = write (fd, buf, remains);
+       if (n_written <= 0)
+         unexec_error ("Write failed for 0x%x bytes at offset 0x%x in %s",
+                       1, bytes, position, "unexec() output file");
+       buf += n_written;
+       remains -= n_written;
+     }
+ 
+   return;
+ }
+ 
+ static void 
+ unexec_pad (int fd, int bytes)
+ {
+   if (bytes > 0)
+     {
+       char buf[1024];
+       int remaining = bytes;
+ 
+       memset (buf, 0, sizeof (buf));
+ 
+       while (remaining > 0)
+         {
+           int this_write = (remaining > sizeof(buf))?sizeof(buf):remaining;
+           unexec_write (fd, -1, buf, this_write);
+           remaining -= this_write;
+         }
+     }
+ }
+ 
+ static void
+ unexec_fstat (int fd, struct stat *statptr)
+ {
+   errno = 0;
+   if (-1 == fstat (fd, statptr))
+     unexec_error ("fstat() failed for descriptor %d", 1, fd);
+   return;
+ }
+ 
+ static void
+ unexec_fchmod (int fd, int mode)
+ {
+   errno = 0;
+   if (-1 == fchmod (fd, mode))
+     unexec_error ("fchmod() failed for descriptor %d", 1, fd);
+   return;
+ }
+ 
+ static long
+ unexec_addr_to_offset (long addr, struct translation_struct *ts)
+                              
+ {
+   if ((addr < ts->txtaddr) || (addr >= ts->bssaddr))
+     return -1;
+   else if (addr >= ts->dataddr)
+     return ((long) ((addr - ts->dataddr) + ts->datoff));
+   else 
+     return ((long) ((addr - ts->txtaddr) + ts->txtoff));
+ }
+ 
+ 
+ /*
+  * "LD.SO" DATA AND SYMBOL TABLE OPERATIONS 
+  */
+ 
+ static void
+ copy_relocation_site (struct relocation_info *ri, 
+                       caddr_t from_base_addr,
+                       caddr_t to_base_addr,
+                       struct translation_struct *ts)
+ {
+   long offset;
+   caddr_t from, to;
+ 
+ #ifndef sparc
+   /* We can get relocation sites in the bss region, for objects whose
+      contents are copied from a shared library.  We don't need or want
+      to restore these at present. */
+   if (ri->r_copy)
+     return;
+ #endif
+ 
+   offset = unexec_addr_to_offset (ri->r_address, ts);
+   if (offset == -1)
+     unexec_error ("bad relocation address 0x%x (0x%x)", 0, ri->r_address,
+ 		  ((long *)ri)[1]);
+ 
+   from = from_base_addr + offset;
+   to = to_base_addr + offset;
+   /* This stuff should be in a md_ file somewhere... */
+ #ifndef sparc
+   switch (ri->r_length)
+     {
+     case 0:
+       *((char *) to) = *((char *) from);
+       break;
+     case 1:
+       *((short *) to) = *((short *) from);
+       break;
+     case 2:
+       *((long *) to) = *((long *) from);
+       break;
+     default:
+       unexec_error ("unknown reloc length %d seen during unexec()",
+ 		    0, ri->r_length);
+       break;
+     }
+ #else /* sparc */
+   switch (ri->r_type)
+     {
+     case RELOC_8:
+     case RELOC_DISP8:
+       *((char *) to) = *((char *) from);
+       break;
+     case RELOC_16:
+     case RELOC_DISP16:
+       *((short *) to) = *((short *) from);
+       break;     
+     case RELOC_LO10:
+     case RELOC_13:     
+     case RELOC_22:     
+     case RELOC_HI22:
+     case RELOC_WDISP22:
+     case RELOC_WDISP30:
+     case RELOC_32:
+     case RELOC_DISP32:
+     case RELOC_GLOB_DAT:
+       *((long *) to) = *((long *) from);
+       break;
+     case RELOC_JMP_SLOT:
+       {
+         long *target = (long *) to;
+         long *source = (long *) from;
+         *target = *source;
+         target++;
+         source++;
+         *target = *source;
+         target++;
+         source++;
+         *target = *source;
+       }
+       break;
+     default:
+       unexec_error ("unknown reloc type %d seen during unexec()",
+ 		    0, ri->r_type);
+     }
+ #endif /* sparc */
+ }
+ 
+ static void
+ reset_symtab (struct nlist *start, struct nlist *end, char *strtab,
+               long edata_value, long end_value, int shlib_image)
+ {
+   struct nlist *tmp = start;
+   int found_edata = 0;
+   int found_end = 0;
+      
+   while (tmp < end)
+     {
+       int type = tmp->n_type;
+ 
+       if ((type == (N_UNDF | N_EXT)) &&
+           (tmp->n_value != 0))
+         unexec_error ("unexec'ing image has COMMON symbols in it -- we quit!",
+ 		      0);
+      
+       if (!(type & N_STAB))
+         {
+           if (!found_edata &&
+               (type == (N_EXT | N_DATA)) &&
+               tmp->n_un.n_strx &&
+               !strcmp ("_edata", strtab + tmp->n_un.n_strx))
+             {
+               tmp->n_value = edata_value;
+               found_edata = 1;
+             }
+ 
+ 
+           if ((type & N_TYPE) == N_BSS)
+             {
+               if (!found_end &&
+                   (type == (N_EXT | N_BSS)) &&
+                   tmp->n_un.n_strx &&
+                   !strcmp ("_end", strtab + tmp->n_un.n_strx))
+                 {
+                   tmp->n_value = end_value;
+                   found_end = 1;
+                 }
+               else if (type & N_EXT)
+                 tmp->n_type = N_DATA | N_EXT;
+               else
+                 tmp->n_type = N_DATA;
+             }
+ 
+           /* the way things are being handled here, having sbrk() in the
+              image is fatal for an image linked with shared lib's (although 
+              the code could be modified to support it), but this should 
+              never happen anyway */
+           if (shlib_image &&
+               (type == (N_EXT | N_TEXT)) &&
+               tmp->n_un.n_strx &&
+               !strcmp ("_sbrk", strtab + tmp->n_un.n_strx))
+             unexec_error ("unexec'd shlib image has sbrk() in it -- we quit!",
+                           0);
+         }
+ 
+       tmp++;
+     }
+ } 
+      
+ static void
+ reset_ldso_symtab (struct nzlist *start, struct nzlist *end, char *strtab,
+               long edata_value, long end_value, int shlib_image)
+ {
+   struct nzlist *tmp = start;
+   int found_edata = 0;
+   int found_end = 0;
+      
+   while (tmp < end) {
+     int type = tmp->nz_type;
+ /*
+  * the following code breaks under FreeBSD-1.1-BETA, but everything
+  * seems to work perfectly if it's commented out.  This did not break
+  * anything until the changes to ld.so were made.
+  */
+ /*
+     if ((type == (N_UNDF | N_EXT)) && (tmp->nz_value != 0))
+       unexec_error("unexec'ing image has COMMON symbols in rel -- we quit!",0);
+ */
+     if (!(type & N_STAB)) {
+       if (!found_edata &&
+ 	  (type == (N_EXT | N_DATA)) &&
+ 	  !strcmp ("_edata", strtab + tmp->nz_strx)) {
+ 	tmp->nz_value = edata_value;
+ 	found_edata = 1;
+       }
+ 
+       if ((type & N_TYPE) == N_BSS) {
+ 	if (!found_end &&
+ 	    (type == (N_EXT | N_BSS)) &&
+ 	    !strcmp ("_end", strtab + tmp->nz_strx)) {
+ 	  tmp->nz_value = end_value;
+ 	  found_end = 1;
+ 	} else if (type & N_EXT)
+ 	  tmp->nz_type = N_DATA | N_EXT;
+ 	else
+ 	  tmp->nz_type = N_DATA;
+       }
+ 
+       /* the way things are being handled here, having sbrk() in the
+ 	 image is fatal for an image linked with shared lib's (although 
+ 	 the code could be modified to support it), but this should 
+ 	 never happen anyway */
+       if (shlib_image &&
+ 	  (type == (N_EXT | N_TEXT)) &&
+ 	  !strcmp ("_sbrk", strtab + tmp->nz_strx))
+ 	unexec_error("unexec'd shlib image has sbrk() ref -- we quit!", 0);
+     }
+     tmp++;
+   }
+ } 
+      
+ extern int getpagesize (void);
+ 
+ /*
+  * EXPORTED FUNCTIONS 
+  */
+ 
+ /* this has to be a global variable to prevent the optimizers from
+  * assuming that it can not be 0.  
+ */
+ static void *dynamic_addr = (void *) &_DYNAMIC;
+ 
+ int
+ unexec (char *new_name, char *old_name,
+         unsigned int emacs_edata, unsigned int dummy1, unsigned int dummy2)
+ {
+   /* ld.so data */
+   struct _dynamic *ld = 0;
+   struct section_dispatch_table *ld2 = 0;
+   /* old and new state */
+   int old_fd;
+   int new_fd;
+   caddr_t old_base_addr;
+   caddr_t new_base_addr;
+   struct exec old_hdr;
+   struct exec new_hdr;
+   struct stat old_buf;
+   struct stat new_buf;
+   /* some process specific "constants" */
+   unsigned long n_pagsiz, new_edata;
+   long page_size = getpagesize ();
+   caddr_t plt_end;
+   caddr_t current_break = (caddr_t) sbrk (0);
+ 
+   if (!page_size)
+     unexec_error ("unexec() failed because we can't get the size of a page!",
+                   0);
+ 
+   /* see if this is a -Bdynamic image -- if so, find ld.so structures */
+   if (dynamic_addr)
+     {
+       ld = (struct _dynamic *) dynamic_addr;
+       ld2 = ld->d_un.d_sdt;
+       if (ld->d_version < LD_VERSION_BSD)
+         unexec_error ("%s linked with obsolete version of ld -- we quit!",
+                       0, old_name);
+     }
+ 
+   /* open the old and new files, figuring out how big the old one is
+      so that we can map it in */
+   old_fd = unexec_open (old_name, O_RDONLY, 0);
+   new_fd = unexec_open (new_name, O_RDWR | O_CREAT | O_TRUNC, 0666);
+ 
+   /* setup the header and the statbuf for old_fd */
+   unexec_read (old_fd, 0, (char *) &old_hdr, sizeof (old_hdr));
+   unexec_fstat (old_fd, &old_buf);
+ 
+ 
+   /* set up some important constants */
+   n_pagsiz = __LDPGSZ;
+   if (dynamic_addr)
+     plt_end = (caddr_t) MASK_UP (ld2->sdt_plt + ld2->sdt_plt_sz, sizeof (double));
+   else
+     plt_end = (caddr_t) N_DATADDR (old_hdr);
+ 
+ #if 0
+   /* never write protect the variable "environ", defined in /lib/crt0.o, and
+      set in process.c and callproc.c */
+   mprotect_bottom_addr = ((unsigned long) &environ) + sizeof (char **);
+   /* never protect ABOVE the end of data emacs_edata specified */
+   mprotect_top_addr = MIN (emacs_edata, N_DATADDR (old_hdr) + old_hdr.a_data);
+ #endif
+ 
+   /* Set up the image of the old file */
+   old_base_addr = unexec_mmap (old_fd, old_buf.st_size, PROT_READ,
+ 			       MAP_PRIVATE);
+   close (old_fd);
+ 
+   /* set up the new exec */
+   new_hdr = old_hdr;
+   new_edata = (unsigned long) MASK_UP (current_break, n_pagsiz);
+   new_hdr.a_data = new_edata - ((unsigned long) N_DATADDR (old_hdr));
+   new_hdr.a_bss  = 0;
+ 
+   /* set up this variable, in case we want to reset "the break" 
+      when restarting */
+   sbrk_of_0_at_unexec = ((unsigned long) MASK_UP (current_break, n_pagsiz));
+      
+   /* Write out the first approximation to the new file. The sizes of
+      each section will be correct, but there will be a number of 
+      corrections that will need to be made. */
+   {
+     long old_datoff = N_DATOFF (old_hdr);
+     long old_dataddr = N_DATADDR (old_hdr);
+ #ifndef sparc
+     long new_treloff = N_RELOFF (new_hdr);
+     long old_treloff = N_RELOFF (old_hdr);
+ #else
+     long new_treloff = N_TRELOFF (new_hdr);
+     long old_treloff = N_TRELOFF (old_hdr);
+ #endif
+     long ld_so_size = ((unsigned long) plt_end) - old_dataddr;
+     long real_data_size = current_break - plt_end;
+     long pad_size = 
+       MASK_UP (current_break, n_pagsiz) - ((unsigned long) current_break);
+ 
+ 
+     /* First, write the text segment with new header -- copy everything until
+        the start of the data segment from the old file, and then go back and 
+        write the new header. */
+     unexec_write (new_fd, 0, old_base_addr, old_datoff + ld_so_size);
+     unexec_write (new_fd, 0, (char *) &new_hdr, sizeof (new_hdr));
+ 
+     /* Copy the rest of the data segment from the running image. */
+     unexec_write (new_fd, old_datoff + ld_so_size, 
+                   plt_end, real_data_size);
+ 
+     /* pad out the data segment */
+     unexec_pad (new_fd, pad_size);
+     
+     /* Finally, copy the symbol table information from the old file. */
+     unexec_write (new_fd, new_treloff,
+                   old_base_addr + old_treloff,
+                   old_buf.st_size - old_treloff);
+   }
+      
+      
+   /* Next, map in the output file so that we can jump around fixing it
+      up. We retain the old file so that we can refer to it. */
+   unexec_fstat (new_fd, &new_buf);
+   new_base_addr = unexec_mmap (new_fd, 
+                                MASK_UP (new_buf.st_size, page_size),
+                                PROT_READ | PROT_WRITE,
+ 			       MAP_SHARED);
+ 
+ 
+ 
+   /* We need to do 2 things. First, make sure that _edata and _end (and
+      hence, curbrk) are set to the correct values. At the same time, for
+      neatness and to help with debugging, mark all the types of all ld.so
+      and nm BSS symbols in the new file to be DATA, and make sure that
+      there are no COMMON symbols in the output file, as any references to
+      these can lose really big. Second, reset all of the ld.so "relocation
+      sites" in the new file to have the values that appear in the old file
+      -- the failure to do this was the biggest loser in the old version of
+      this code. */
+ 
+   /* STEP 1 */
+   /* Reset the regular symbol table first. */
+   reset_symtab ((struct nlist *) (new_base_addr + N_SYMOFF(new_hdr)),
+ 		(struct nlist *) (new_base_addr + N_SYMOFF(new_hdr) +
+ 				  new_hdr.a_syms),
+ 		(char *) (new_base_addr + N_STROFF(new_hdr)),
+ 		new_edata, new_edata,
+ 		!!dynamic_addr);
+ 
+   /* Now reset the ld.so symbol table. */
+   if (dynamic_addr)
+     {
+       struct translation_struct ts;
+       struct relocation_info *tmp, *end;
+       caddr_t syms, strings;
+ 
+       /* set up the structure that we use to translate addresses in the
+ 	 old file into file offsets */
+       ts.txtaddr = N_TXTADDR (old_hdr);
+       ts.txtoff = N_TXTOFF (old_hdr);
+       ts.dataddr = N_DATADDR (old_hdr);
+       ts.datoff = N_DATOFF (old_hdr);
+       ts.bssaddr = N_DATADDR (old_hdr) + old_hdr.a_data;
+       ts.endaddr = ts.bssaddr + old_hdr.a_bss;
+ 
+       syms = new_base_addr + unexec_addr_to_offset(ld2->sdt_nzlist, &ts);
+       strings = new_base_addr + unexec_addr_to_offset(ld2->sdt_strings, &ts);
+       reset_ldso_symtab ((struct nzlist *) syms, (struct nzlist *) strings,
+ 			 (char *) strings,
+ 			 new_edata, new_edata,
+ 			 !!dynamic_addr);
+ 
+       /* STEP 2 */
+       tmp = (struct relocation_info *)
+ 	(old_base_addr + unexec_addr_to_offset(ld2->sdt_rel, &ts));
+       end = (struct relocation_info *)
+ 	(old_base_addr + unexec_addr_to_offset(ld2->sdt_hash, &ts));
+       while (tmp < end)
+ 	{
+ 	  copy_relocation_site (tmp, old_base_addr, new_base_addr, &ts);
+ 	  tmp++;
+ 	}
+     }
+      
+   /* get rid of the mmap-ed file space and make the output file 
+      executable -- then quit */
+   munmap (new_base_addr, MASK_UP (new_buf.st_size, page_size));
+   munmap (old_base_addr, MASK_UP (old_buf.st_size, page_size));
+   unexec_fchmod (new_fd, 0755);
+   close (new_fd);
+   return 0;
+ }
+ 
+ 
+ int
+ run_time_remap (char *dummy)
+ {
+       unsigned long current_sbrk = (unsigned long) sbrk (0);
+ 
+       if (sbrk_of_0_at_unexec < current_sbrk)
+ 	{
+ 	  if (sbrk_of_0_at_unexec != 0)
+ 	    fprintf (stderr, "Absurd new brk addr = 0x%x (current = 0x%x)\n", 
+ 		     sbrk_of_0_at_unexec, current_sbrk);
+ 	}
+       else
+         {
+           errno = 0;
+           if (brk ((caddr_t) sbrk_of_0_at_unexec))
+             fprintf (stderr, "failed to change brk addr to 0x%x: %s\n", 
+                      sbrk_of_0_at_unexec, SYS_ERR);
+         }
+ 
+ #if 0
+ /* with proper COW, i don't think we really need to do this... */
+   {
+     long page_size = getpagesize();
+     unsigned long base_addr = MASK_UP (mprotect_bottom_addr, page_size);
+     unsigned long top_addr = MASK_DOWN (mprotect_top_addr, page_size);
+     long len = top_addr - base_addr;
+ 
+     if (len > 0)
+       {
+         errno = 0;
+         if (mprotect ((caddr_t) base_addr, len, PROT_READ | PROT_EXEC))
+           fprintf (stderr, "failed to change protection on data pages: %s\n",
+                    SYS_ERR);
+       }
+   }
+ #endif
+              
+   return 0;
+ }

------------------------------------------------------------------------------