/* Unexec for Sunos 4 using shared libraries.
- Copyright (C) 1990, 1994 Free Software Foundation, Inc.
+ Copyright (C) 1990, 1994, 1999 Free Software Foundation, Inc.
This file is part of GNU Emacs.
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. */
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
/* Contributed by Viktor Dukhovni. */
/*
* is somewhat abused here) is loaded first!
*
*/
+
+#ifdef emacs
+#include <config.h>
+#endif
+
#include <sys/param.h>
#include <sys/mman.h>
#include <sys/file.h>
#include <stdio.h>
#include <a.out.h>
-/* Do this after the above #include's in case a configuration file wants
- to define things for this file based on what <a.out.h> defines. */
-#ifdef emacs
-#include <config.h>
-#endif
-
-#if defined (SUNOS4) || defined (__FreeBSD__)
+#if defined (SUNOS4) || defined (__FreeBSD__) || defined (__NetBSD__)
#define UNDO_RELOCATION
#endif
#include <link.h>
#endif
-#ifdef __FreeBSD__
-#define link_dynamic _dynamic
-#define ld_un d_un
-#define ld_2 d_sdt
-#define ld_rel sdt_rel
-#define ld_hash sdt_hash
-#endif /* __FreeBSD__ */
-
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#endif
extern char *getenv ();
-static unsigned Brk;
+static unsigned brk_value;
static struct exec nhdr;
static int rd_only_len;
static long cookie;
struct exec ohdr; /* Allocate on the stack, not needed in the next life */
struct stat stat;
-#ifdef emacs
- fprintf (stderr, "Used %d bytes of Pure Storage\n", pureptr);
-#endif
-
if ((fd = open (a_name, O_RDONLY)) < 0)
{
fprintf (stderr, "%s: open: ", a_name);
*/
cookie = time (0);
- Brk = sbrk (0); /* Save the break, it is reset to &_end (by ld.so?) */
+ /* Save the break, it is reset to &_end (by ld.so?). */
+ brk_value = (unsigned) sbrk (0);
/*
* Round up data start to a page boundary (Lose if not a 2 power!)
initialized = 1;
#endif
- /*
- * Handle new data and bss sizes and optional new entry point.
- * No one actually uses bss_start and entry, but tradition compels
- * one to support them.
- * Could complain if bss_start > Brk, but the caller is *supposed* to know
- * what she is doing.
- */
- nhdr.a_data = (bss_start ? bss_start : Brk) - N_DATADDR (nhdr);
- nhdr.a_bss = bss_start ? Brk - bss_start : 0;
+ /* Handle new data and bss sizes and optional new entry point.
+ No one actually uses bss_start and entry, but tradition compels
+ one to support them.
+ Could complain if bss_start > brk_value,
+ but the caller is *supposed* to know what she is doing. */
+ nhdr.a_data = (bss_start ? bss_start : brk_value) - N_DATADDR (nhdr);
+ nhdr.a_bss = bss_start ? brk_value - bss_start : 0;
if (entry)
nhdr.a_entry = entry;
It will do these relocations again when we start the dumped Emacs.
Doing them twice gives incorrect results. */
{
- extern struct link_dynamic _DYNAMIC;
- unsigned long taddr = N_TXTADDR (ohdr) - N_TXTOFF (ohdr);
- unsigned long daddr = N_DATADDR (ohdr) - N_DATOFF (ohdr);
+ unsigned long daddr = N_DATADDR (ohdr);
unsigned long rel, erel;
- unsigned rel_size;
-
#ifdef SUNOS4
- if (_DYNAMIC.ld_version < 2)
+#ifdef SUNOS4_SHARED_LIBRARIES
+ extern struct link_dynamic _DYNAMIC;
+
+ /* SunOS4.x's ld_rel is relative to N_TXTADDR. */
+ if (!ohdr.a_dynamic)
+ /* This was statically linked. */
+ rel = erel = 0;
+ else if (_DYNAMIC.ld_version < 2)
{
- rel = _DYNAMIC.ld_un.ld_1->ld_rel;
- erel = _DYNAMIC.ld_un.ld_1->ld_hash;
+ rel = _DYNAMIC.ld_un.ld_1->ld_rel + N_TXTADDR (ohdr);
+ erel = _DYNAMIC.ld_un.ld_1->ld_hash + N_TXTADDR (ohdr);
}
else
{
- rel = _DYNAMIC.ld_un.ld_2->ld_rel;
- erel = _DYNAMIC.ld_un.ld_2->ld_hash;
- }
-
- switch (ohdr.a_machtype)
- {
- case M_68010:
- case M_68020:
- rel_size = 8; /* sizeof(struct reloc_info_m68k) */
- break;
- case M_SPARC:
- rel_size = 12; /* sizeof(struct reloc_info_sparc) */
- break;
- case M_OLDSUN2:
- default:
- fatal ("unknown machine type in unexec!\n");
+ rel = _DYNAMIC.ld_un.ld_2->ld_rel + N_TXTADDR (ohdr);
+ erel = _DYNAMIC.ld_un.ld_2->ld_hash + N_TXTADDR (ohdr);
}
+#else /* not SUNOS4_SHARED_LIBRARIES */
+ rel = erel = 0;
+#endif /* not SUNOS4_SHARED_LIBRARIES */
+#ifdef sparc
+#define REL_INFO_TYPE struct reloc_info_sparc
+#else
+#define REL_INFO_TYPE struct relocation_info
+#endif /* sparc */
+#define REL_TARGET_ADDRESS(r) (((REL_INFO_TYPE *)(r))->r_address)
#endif /* SUNOS4 */
-#ifdef __FreeBSD__
- rel = _DYNAMIC.ld_un.ld_2->ld_rel;
- erel = _DYNAMIC.ld_un.ld_2->ld_hash;
- rel_size = 8; /* sizeof(struct relocation_info) */
+#if defined (__FreeBSD__) || defined (__NetBSD__)
+ extern struct _dynamic _DYNAMIC;
+
+ /* FreeBSD's LD_REL is a virtual address itself. */
+ rel = LD_REL (&_DYNAMIC);
+ erel = rel + LD_RELSZ (&_DYNAMIC);
+#define REL_INFO_TYPE struct relocation_info
+#define REL_TARGET_ADDRESS(r) (((REL_INFO_TYPE *)(r))->r_address)
#endif
- for (; rel < erel; rel += rel_size)
+ for (; rel < erel; rel += sizeof (REL_INFO_TYPE))
{
- /* This is the unadjusted address from the reloc. */
- unsigned long pos = *(unsigned long *)(taddr + rel);
- /* This is the amount by which to adjust it. It
- depends on which segment the address belongs to. */
- unsigned long offset = (pos < (unsigned long)&data_start
- ? taddr : daddr);
- /* This is the adjusted address from the reloc. */
- unsigned long rpos = pos - offset;
-
- lseek (new, N_TXTOFF (nhdr) + rpos, L_SET);
- write (new, old + N_TXTOFF (ohdr) + rpos, sizeof (unsigned long));
+ /* This is the virtual address where ld.so will do relocation. */
+ unsigned long target = REL_TARGET_ADDRESS (rel);
+ /* This is the offset in the data segment. */
+ unsigned long segoffset = target - daddr;
+
+ /* If it is located below data_start, we have to do nothing here,
+ because the old data has been already written to the location. */
+ if (target < (unsigned long)&data_start)
+ continue;
+
+ lseek (new, N_DATOFF (nhdr) + segoffset, L_SET);
+ write (new, old + N_DATOFF (ohdr) + segoffset, sizeof (unsigned long));
}
}
#endif /* UNDO_RELOCATION */
return;
/* Restore the break */
- brk (Brk);
+ brk ((char *) brk_value);
/* If nothing to remap: we are done! */
if (rd_only_len == 0)
}
}
-is_it (path)
- char *path;
+is_it (filename)
+ char *filename;
{
int fd;
- long paths_cookie;
+ long filenames_cookie;
struct exec hdr;
/*
* Open an executable and check for a valid header!
- * Can't bcmp() the header with what we had, it may have been stripped!
+ * Can't bcmp the header with what we had, it may have been stripped!
* so we may save looking at non executables with the same name, mostly
* directories.
*/
- fd = open (path, O_RDONLY);
+ fd = open (filename, O_RDONLY);
if (fd != -1)
{
if (read (fd, &hdr, sizeof (hdr)) == sizeof (hdr)
{
/* compare cookies */
lseek (fd, N_DATOFF (hdr) + (int)&cookie - N_DATADDR (hdr), L_SET);
- read (fd, &paths_cookie, sizeof (paths_cookie));
- if (paths_cookie == cookie)
+ read (fd, &filenames_cookie, sizeof (filenames_cookie));
+ if (filenames_cookie == cookie)
{ /* Eureka */
/*
* should the shared library decide to indirect through
* addresses in the data segment not part of __DYNAMIC
*/
- mmap (data_start, rd_only_len, PROT_READ | PROT_EXEC,
+ mmap ((char *) data_start, rd_only_len, PROT_READ | PROT_EXEC,
MAP_FILE | MAP_SHARED | MAP_FIXED, fd,
N_DATOFF (hdr) + data_start - N_DATADDR (hdr));
close (fd);
HCoop / bpt / emacs.git / blobdiff