696 lines
20 KiB
Plaintext
696 lines
20 KiB
Plaintext
--- src/unexfreebsd.c.orig Wed Dec 3 17:28:14 1997
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+++ src/unexfreebsd.c Wed Dec 3 17:34:02 1997
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@@ -0,0 +1,692 @@
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+/* Code to do an unexec for FreeBSD for a temacs linked -Bdynamic.
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+ Derived from unexnetbsd.c, which was derived from unexsunos4.c
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+ Copyright (C) 1992, 1993 Free Software Foundation, Inc.
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+
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+This file is part of XEmacs.
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+
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+XEmacs is free software; you can redistribute it and/or modify it
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+under the terms of the GNU General Public License as published by the
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+Free Software Foundation; either version 2, or (at your option) any
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+later version.
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+
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+XEmacs is distributed in the hope that it will be useful, but WITHOUT
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+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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+for more details.
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+
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+You should have received a copy of the GNU General Public License
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+along with XEmacs; see the file COPYING. If not, write to
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+the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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+Boston, MA 02111-1307, USA. */
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+
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+/* Synched up with: Not in FSF? */
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+
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+/*
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+Created 29-Oct-92 by Harlan Sexton
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+Tweaked 06-Aug-93 by Dean Michaels to work with sun3.
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+Converted 01-Dec-93 by Paul Mackerras to work with NetBSD shared libraries.
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+Tweaked 26-Feb-94 by Shawn Carey for use with FreeBSD-1.1 shared libraries.
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+*/
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+
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+/********************** Included .h Files **************************/
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+
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+#include <config.h>
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+
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+#include <stdarg.h>
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+#include <sys/param.h>
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+#include <sys/mman.h>
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+#include <sys/file.h>
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+#include <sys/stat.h>
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+#include <sys/types.h>
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+#include <string.h>
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+#include <stdio.h>
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+#include <a.out.h>
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+#include <unistd.h>
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+#include <ctype.h>
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+#include <stab.h>
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+#include <dirent.h>
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+#include <link.h>
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+
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+/********************** Macros *************************************/
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+
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+#define SYS_ERR strerror(errno)
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+
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+#define MASK_UP(x,p_of_two) \
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+ ((((unsigned long) (x)) + ((p_of_two) - 1)) & (~((p_of_two) - 1)))
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+
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+#define MASK_DOWN(x,p_of_two) (((unsigned long) (x)) & (~((p_of_two) - 1)))
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+
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+/********************** Typedefs and Structs ***********************/
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+
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+struct translation_struct
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+{
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+ long txtaddr;
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+ long txtoff;
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+ long dataddr;
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+ long datoff;
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+ long bssaddr;
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+ long endaddr;
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+};
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+
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+/********************** Function Prototypes/Declarations ***********/
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+
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+static void unexec_error (const char *m, int use_errno, ...);
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+static int unexec_open (char *filename, int flag, int mode);
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+static caddr_t unexec_mmap (int fd, size_t len, int prot, int flags);
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+static long unexec_seek (int fd, long position);
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+static void unexec_read (int fd, long position, char *buf, int bytes);
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+static void unexec_write (int fd, long position, char *buf, int bytes);
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+static void unexec_pad (int fd, int bytes);
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+static void unexec_fstat (int fd, struct stat *statptr);
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+static void unexec_fchmod (int fd, int mode);
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+static long unexec_addr_to_offset (long addr, struct translation_struct *ts);
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+static void copy_relocation_site (struct relocation_info *ri,
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+ caddr_t from_base_addr,
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+ caddr_t to_base_addr,
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+ struct translation_struct *ts);
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+static void reset_symtab (struct nlist *start, struct nlist *end,
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+ char *strtab, long edata_value, long end_value,
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+ int shlib_image);
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+static void reset_ldso_symtab (struct nzlist *start, struct nzlist *end,
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+ char *strtab, long edata_value, long end_value,
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+ int shlib_image);
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+int run_time_remap (char *dummy);
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+
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+/********************** Variables **********************************/
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+
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+/* for reporting error messages from system calls */
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+extern int errno;
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+extern int _DYNAMIC;
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+extern char **environ;
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+
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+static unsigned long sbrk_of_0_at_unexec;
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+
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+/*******************************************************************/
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+
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+static void
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+unexec_error (const char *fmt, int use_errno, ...)
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+{
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+ const char *err_msg = SYS_ERR;
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+ va_list args;
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+
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+ fprintf (stderr, "unexec - ");
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+ va_start (args, use_errno);
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+ vfprintf (stderr, fmt, args);
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+ va_end (args);
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+
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+ if (use_errno)
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+ fprintf (stderr, ": %s", err_msg);
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+ fprintf (stderr, "\n");
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+ exit (1);
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+ return;
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+}
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+
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+static int
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+unexec_open (char *filename, int flag, int mode)
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+{
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+ int fd;
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+
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+ errno = 0;
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+
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+ fd = open (filename, flag, mode);
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+
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+ if (fd < 0)
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+ unexec_error ("Failure opening file %s", 1, filename);
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+ return fd;
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+}
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+
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+static caddr_t
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+unexec_mmap (int fd, size_t len, int prot, int flags)
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+{
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+ caddr_t return_val;
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+
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+ unexec_seek (fd, 0);
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+ errno = 0;
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+ return_val = mmap (0, len, prot, flags, fd, 0);
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+
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+ if (return_val == (caddr_t) -1)
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+ unexec_error ("Failure mmap'ing file", 1);
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+ return return_val;
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+}
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+
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+
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+static long
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+unexec_seek (int fd, long position)
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+{
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+ long seek_value;
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+
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+ if (fd <= 0)
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+ unexec_error ("No file open in which to seek", 0);
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+
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+ errno = 0;
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+
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+ if (position < 0)
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+ seek_value = (long) lseek (fd, 0, L_INCR);
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+ else
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+ seek_value = (long) lseek (fd, position, L_SET);
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+
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+ if (seek_value < 0)
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+ unexec_error ("Failed to do a seek to 0x%x in %s", 1,
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+ position, "unexec() output file");
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+
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+ return seek_value;
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+}
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+
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+static void
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+unexec_read (int fd, long position, char *buf, int bytes)
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+{
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+ int n_read;
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+ int remains = bytes;
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+ position = unexec_seek (fd, position);
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+
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+ if (bytes < 0)
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+ unexec_error ("Attempted read of %d bytes", 0, bytes);
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+
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+ errno = 0;
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+
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+ while (remains > 0)
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+ {
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+ n_read = read (fd, buf, remains);
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+ if (n_read <= 0)
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+ unexec_error ("Read failed for 0x%x bytes at offset 0x%x in %s",
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+ 1, bytes, position, "unexec() output file");
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+ buf += n_read;
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+ remains -= n_read;
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+ }
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+
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+ return;
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+}
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+
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+static void
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+unexec_write (int fd, long position, char *buf, int bytes)
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+{
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+ int n_written;
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+ int remains = bytes;
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+ position = unexec_seek (fd, position);
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+
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+ if (bytes < 0)
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+ unexec_error ("Attempted write of %d bytes in %s",
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+ 0, bytes, "unexec() output file");
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+
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+ errno = 0;
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+
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+ while (remains > 0)
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+ {
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+ n_written = write (fd, buf, remains);
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+ if (n_written <= 0)
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+ unexec_error ("Write failed for 0x%x bytes at offset 0x%x in %s",
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+ 1, bytes, position, "unexec() output file");
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+ buf += n_written;
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+ remains -= n_written;
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+ }
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+
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+ return;
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+}
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+
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+static void
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+unexec_pad (int fd, int bytes)
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+{
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+ if (bytes > 0)
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+ {
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+ char buf[1024];
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+ int remaining = bytes;
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+
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+ memset (buf, 0, sizeof (buf));
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+
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+ while (remaining > 0)
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+ {
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+ int this_write = (remaining > sizeof(buf))?sizeof(buf):remaining;
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+ unexec_write (fd, -1, buf, this_write);
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+ remaining -= this_write;
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+ }
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+ }
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+}
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+
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+static void
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+unexec_fstat (int fd, struct stat *statptr)
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+{
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+ errno = 0;
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+ if (-1 == fstat (fd, statptr))
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+ unexec_error ("fstat() failed for descriptor %d", 1, fd);
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+ return;
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+}
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+
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+static void
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+unexec_fchmod (int fd, int mode)
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+{
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+ errno = 0;
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+ if (-1 == fchmod (fd, mode))
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+ unexec_error ("fchmod() failed for descriptor %d", 1, fd);
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+ return;
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+}
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+
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+static long
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+unexec_addr_to_offset (long addr, struct translation_struct *ts)
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+
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+{
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+ if ((addr < ts->txtaddr) || (addr >= ts->bssaddr))
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+ return -1;
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+ else if (addr >= ts->dataddr)
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+ return ((long) ((addr - ts->dataddr) + ts->datoff));
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+ else
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+ return ((long) ((addr - ts->txtaddr) + ts->txtoff));
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+}
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+
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+
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+/*
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+ * "LD.SO" DATA AND SYMBOL TABLE OPERATIONS
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+ */
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+
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+static void
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+copy_relocation_site (struct relocation_info *ri,
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+ caddr_t from_base_addr,
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+ caddr_t to_base_addr,
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+ struct translation_struct *ts)
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+{
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+ long offset;
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+ caddr_t from, to;
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+
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+ /* We can get relocation sites in the bss region, for objects whose
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+ contents are copied from a shared library. We don't need or want
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+ to restore these at present. */
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+#ifndef sparc
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+ if (ri->r_copy)
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+ return;
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+#else
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+ /* Struct relocation_info_sparc doesn't have member r_copy.
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+ Instead, we use the address to check if this is run-time-copied. */
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+ if (ri->r_address >= ts->bssaddr && ri->r_address < ts->endaddr)
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+ return;
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+#endif
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+
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+ offset = unexec_addr_to_offset (ri->r_address, ts);
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+ if (offset == -1)
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+ unexec_error ("bad relocation address 0x%x (0x%x)", 0, ri->r_address,
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+ ((long *)ri)[1]);
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+
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+ from = from_base_addr + offset;
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+ to = to_base_addr + offset;
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+ /* This stuff should be in a md_ file somewhere... */
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+#ifndef sparc
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+ switch (ri->r_length)
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+ {
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+ case 0:
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+ *((char *) to) = *((char *) from);
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+ break;
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+ case 1:
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+ *((short *) to) = *((short *) from);
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+ break;
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+ case 2:
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+ *((long *) to) = *((long *) from);
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+ break;
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+ default:
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+ unexec_error ("unknown reloc length %d seen during unexec()",
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+ 0, ri->r_length);
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+ break;
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+ }
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+#else /* sparc */
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+ switch (ri->r_type)
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+ {
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+ case RELOC_8:
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+ case RELOC_DISP8:
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+ *((char *) to) = *((char *) from);
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+ break;
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+ case RELOC_16:
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+ case RELOC_DISP16:
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+ *((short *) to) = *((short *) from);
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+ break;
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+ case RELOC_LO10:
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+ case RELOC_13:
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+ case RELOC_22:
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+ case RELOC_HI22:
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+ case RELOC_WDISP22:
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+ case RELOC_WDISP30:
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+ case RELOC_32:
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+ case RELOC_DISP32:
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+ case RELOC_GLOB_DAT:
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+ *((long *) to) = *((long *) from);
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+ break;
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+ case RELOC_JMP_SLOT:
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+ {
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+ long *target = (long *) to;
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+ long *source = (long *) from;
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+ *target = *source;
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+ target++;
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+ source++;
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+ *target = *source;
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+ target++;
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+ source++;
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+ *target = *source;
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+ }
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+ break;
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+ default:
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+ unexec_error ("unknown reloc type %d seen during unexec()",
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+ 0, ri->r_type);
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+ break;
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+ }
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+#endif /* sparc */
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+}
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+
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+static void
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+reset_symtab (struct nlist *start, struct nlist *end, char *strtab,
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+ long edata_value, long end_value, int shlib_image)
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+{
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+ struct nlist *tmp = start;
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+ int found_edata = 0;
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+ int found_end = 0;
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+
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+ while (tmp < end)
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+ {
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+ int type = tmp->n_type;
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+
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+ if ((type == (N_UNDF | N_EXT)) &&
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+ (tmp->n_value != 0))
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+ unexec_error ("unexec'ing image has COMMON symbols in it -- we quit!",
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+ 0);
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+
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+ if (!(type & N_STAB))
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+ {
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+ if (!found_edata &&
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+ (type == (N_EXT | N_DATA)) &&
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+ tmp->n_un.n_strx &&
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+ !strcmp ("_edata", strtab + tmp->n_un.n_strx))
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+ {
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+ tmp->n_value = edata_value;
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+ found_edata = 1;
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+ }
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+
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+
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+ if ((type & N_TYPE) == N_BSS)
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+ {
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+ if (!found_end &&
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+ (type == (N_EXT | N_BSS)) &&
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+ tmp->n_un.n_strx &&
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+ !strcmp ("_end", strtab + tmp->n_un.n_strx))
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+ {
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+ tmp->n_value = end_value;
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+ found_end = 1;
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+ }
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+ else if (type & N_EXT)
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+ tmp->n_type = N_DATA | N_EXT;
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+ else
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+ tmp->n_type = N_DATA;
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+ }
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+
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+ /* the way things are being handled here, having sbrk() in the
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+ image is fatal for an image linked with shared lib's (although
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+ the code could be modified to support it), but this should
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+ never happen anyway */
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+ if (shlib_image &&
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+ (type == (N_EXT | N_TEXT)) &&
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+ tmp->n_un.n_strx &&
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+ !strcmp ("_sbrk", strtab + tmp->n_un.n_strx))
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+ unexec_error ("unexec'd shlib image has sbrk() in it -- we quit!",
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+ 0);
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+ }
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+
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+ tmp++;
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+ }
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+}
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+
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+static void
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+reset_ldso_symtab (struct nzlist *start, struct nzlist *end, char *strtab,
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+ long edata_value, long end_value, int shlib_image)
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+{
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+ struct nzlist *tmp = start;
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+ int found_edata = 0;
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+ int found_end = 0;
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+
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+ while (tmp < end) {
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+ int type = tmp->nz_type;
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+/*
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+ * the following code breaks under FreeBSD-1.1-BETA, but everything
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+ * seems to work perfectly if it's commented out. This did not break
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+ * anything until the changes to ld.so were made.
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+ */
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+/*
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+ if ((type == (N_UNDF | N_EXT)) && (tmp->nz_value != 0))
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+ unexec_error("unexec'ing image has COMMON symbols in rel -- we quit!",0);
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+*/
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+ if (!(type & N_STAB)) {
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+ if (!found_edata &&
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+ (type == (N_EXT | N_DATA)) &&
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+ !strcmp ("_edata", strtab + tmp->nz_strx)) {
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+ tmp->nz_value = edata_value;
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+ found_edata = 1;
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+ }
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+
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+ if ((type & N_TYPE) == N_BSS) {
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+ if (!found_end &&
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+ (type == (N_EXT | N_BSS)) &&
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+ !strcmp ("_end", strtab + tmp->nz_strx)) {
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+ tmp->nz_value = end_value;
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+ found_end = 1;
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+ } else if (type & N_EXT)
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+ tmp->nz_type = N_DATA | N_EXT;
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+ else
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+ tmp->nz_type = N_DATA;
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+ }
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+
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+ /* the way things are being handled here, having sbrk() in the
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+ image is fatal for an image linked with shared lib's (although
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+ the code could be modified to support it), but this should
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+ never happen anyway */
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+ if (shlib_image &&
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+ (type == (N_EXT | N_TEXT)) &&
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+ !strcmp ("_sbrk", strtab + tmp->nz_strx))
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+ unexec_error("unexec'd shlib image has sbrk() ref -- we quit!", 0);
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+ }
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+ tmp++;
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+ }
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+}
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+
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+extern int getpagesize (void);
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+
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+/*
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+ * EXPORTED FUNCTIONS
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+ */
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+
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+/* this has to be a global variable to prevent the optimizers from
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+ * assuming that it can not be 0.
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+*/
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+static void *dynamic_addr = (void *) &_DYNAMIC;
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+
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+int
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+unexec (char *new_name, char *old_name,
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+ unsigned int emacs_edata, unsigned int dummy1, unsigned int dummy2)
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+{
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+ /* 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_FILE | 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);
|
|
+ long new_treloff = N_RELOFF (new_hdr);
|
|
+ long old_treloff = N_RELOFF (old_hdr);
|
|
+ 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_FILE | 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)
|
|
+ {
|
|
+ errno = 0;
|
|
+ if (brk ((caddr_t) sbrk_of_0_at_unexec))
|
|
+ fprintf (stderr, "failed to change brk addr to 0x%lx: %s\n",
|
|
+ sbrk_of_0_at_unexec, SYS_ERR);
|
|
+ }
|
|
+
|
|
+ return 0;
|
|
+}
|