Initial revision

1 files changed, 305 insertions, 0 deletions

diff --git a/src/unexmips.c b/src/unexmips.c
new file mode 100644
index 00000000000..8cfdd401b40
--- /dev/null
+++ b/src/unexmips.c
@@ -0,0 +1,305 @@
+/* Unexec for MIPS (including IRIS4D).
+   Note that the GNU project considers support for MIPS operation
+   a peripheral activity which should not be allowed to divert effort
+   from development of the GNU system.  Changes in this code will be
+   installed when users send them in, but aside from that
+   we don't plan to think about it, or about whether other Emacs
+   maintenance might break it.
+
+   Copyright (C) 1988 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 1, 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.  */
+
+
+#include "config.h"
+#include <sys/types.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <stdio.h>
+#include <varargs.h>
+#include <filehdr.h>
+#include <aouthdr.h>
+#include <scnhdr.h>
+#include <sym.h>
+
+#ifdef IRIS_4D
+#include "getpagesize.h"
+#endif
+
+static void fatal_unexec ();
+
+#define READ(_fd, _buffer, _size, _error_message, _error_arg) \
+	errno = EEOF; \
+	if (read (_fd, _buffer, _size) != _size) \
+	  fatal_unexec (_error_message, _error_arg);
+
+#define WRITE(_fd, _buffer, _size, _error_message, _error_arg) \
+	if (write (_fd, _buffer, _size) != _size) \
+	  fatal_unexec (_error_message, _error_arg);
+
+#define SEEK(_fd, _position, _error_message, _error_arg) \
+	errno = EEOF; \
+	if (lseek (_fd, _position, L_SET) != _position) \
+	  fatal_unexec (_error_message, _error_arg);
+
+extern int errno;
+extern int sys_nerr;
+extern char *sys_errlist[];
+#define EEOF -1
+
+static struct scnhdr *text_section;
+static struct scnhdr *init_section;
+static struct scnhdr *finit_section;
+static struct scnhdr *rdata_section;
+static struct scnhdr *data_section;
+static struct scnhdr *lit8_section;
+static struct scnhdr *lit4_section;
+static struct scnhdr *sdata_section;
+static struct scnhdr *sbss_section;
+static struct scnhdr *bss_section;
+
+struct headers {
+    struct filehdr fhdr;
+    struct aouthdr aout;
+    struct scnhdr section[10];
+};
+
+/* Define name of label for entry point for the dumped executable.  */
+
+#ifndef DEFAULT_ENTRY_ADDRESS
+#define DEFAULT_ENTRY_ADDRESS __start
+#endif
+
+unexec (new_name, a_name, data_start, bss_start, entry_address)
+     char *new_name, *a_name;
+     unsigned data_start, bss_start, entry_address;
+{
+  int new, old;
+  int pagesize, brk;
+  int newsyms, symrel;
+  int nread;
+  struct headers hdr;
+  int i;
+  int vaddr, scnptr;
+#define BUFSIZE 8192
+  char buffer[BUFSIZE];
+
+  old = open (a_name, O_RDONLY, 0);
+  if (old < 0) fatal_unexec ("opening %s", a_name);
+
+  new = creat (new_name, 0666);
+  if (new < 0) fatal_unexec ("creating %s", new_name);
+
+  hdr = *((struct headers *)TEXT_START);
+#ifdef MIPS2
+  if (hdr.fhdr.f_magic != MIPSELMAGIC
+      && hdr.fhdr.f_magic != MIPSEBMAGIC
+      && hdr.fhdr.f_magic != (MIPSELMAGIC | 1)
+      && hdr.fhdr.f_magic != (MIPSEBMAGIC | 1))
+    {
+      fprintf(stderr,
+	      "unexec: input file magic number is %x, not %x, %x, %x or %x.\n",
+	      hdr.fhdr.f_magic,
+	      MIPSELMAGIC, MIPSEBMAGIC,
+	      MIPSELMAGIC | 1, MIPSEBMAGIC | 1);
+      exit(1);
+    }
+#else /* not MIPS2 */
+  if (hdr.fhdr.f_magic != MIPSELMAGIC
+      && hdr.fhdr.f_magic != MIPSEBMAGIC)
+    {
+      fprintf (stderr, "unexec: input file magic number is %x, not %x or %x.\n",
+	       hdr.fhdr.f_magic, MIPSELMAGIC, MIPSEBMAGIC);
+      exit (1);
+    }
+#endif /* not MIPS2 */
+  if (hdr.fhdr.f_opthdr != sizeof (hdr.aout))
+    {
+      fprintf (stderr, "unexec: input a.out header is %d bytes, not %d.\n",
+	       hdr.fhdr.f_opthdr, sizeof (hdr.aout));
+      exit (1);
+    }
+  if (hdr.aout.magic != ZMAGIC)
+    {
+      fprintf (stderr, "unexec: input file a.out magic number is %o, not %o.\n",
+	       hdr.aout.magic, ZMAGIC);
+      exit (1);
+    }
+
+#define CHECK_SCNHDR(ptr, name, flags)					\
+  if (strcmp (hdr.section[i].s_name, name) == 0)			\
+    {									\
+      if (hdr.section[i].s_flags != flags)				\
+	fprintf (stderr, "unexec: %x flags (%x expected) in %s section.\n", \
+		 hdr.section[i].s_flags, flags, name);			\
+      ptr = hdr.section + i;						\
+      i += 1;								\
+    }									\
+  else									\
+    ptr = NULL;
+
+  i = 0;
+  CHECK_SCNHDR (text_section,  _TEXT,  STYP_TEXT);
+  CHECK_SCNHDR (init_section,  _INIT,  STYP_INIT);
+  CHECK_SCNHDR (rdata_section, _RDATA, STYP_RDATA);
+  CHECK_SCNHDR (data_section,  _DATA,  STYP_DATA);
+#ifdef _LIT8
+  CHECK_SCNHDR (lit8_section,  _LIT8,  STYP_LIT8);
+  CHECK_SCNHDR (lit4_section,  _LIT4,  STYP_LIT4);
+#endif /* _LIT8 */
+  CHECK_SCNHDR (sdata_section, _SDATA, STYP_SDATA);
+  CHECK_SCNHDR (sbss_section,  _SBSS,  STYP_SBSS);
+  CHECK_SCNHDR (bss_section,   _BSS,   STYP_BSS);
+  if (i != hdr.fhdr.f_nscns)
+    fprintf (stderr, "unexec: %d sections found instead of %d.\n",
+	     i, hdr.fhdr.f_nscns);
+
+  pagesize = getpagesize ();
+  brk = (sbrk (0) + pagesize - 1) & (-pagesize);
+  hdr.aout.dsize = brk - DATA_START;
+  hdr.aout.bsize = 0;
+  if (entry_address == 0)
+    {
+      extern DEFAULT_ENTRY_ADDRESS ();
+      hdr.aout.entry = (unsigned)DEFAULT_ENTRY_ADDRESS;
+    }
+  else
+    hdr.aout.entry = entry_address;
+
+  hdr.aout.bss_start = hdr.aout.data_start + hdr.aout.dsize;
+  rdata_section->s_size = data_start - DATA_START;
+  data_section->s_vaddr = data_start;
+  data_section->s_paddr = data_start;
+  data_section->s_size = brk - DATA_START;
+  data_section->s_scnptr = rdata_section->s_scnptr + rdata_section->s_size;
+  vaddr = data_section->s_vaddr + data_section->s_size;
+  scnptr = data_section->s_scnptr + data_section->s_size;
+  if (lit8_section != NULL)
+    {
+      lit8_section->s_vaddr = vaddr;
+      lit8_section->s_paddr = vaddr;
+      lit8_section->s_size = 0;
+      lit8_section->s_scnptr = scnptr;
+    }
+  if (lit4_section != NULL)
+    {
+      lit4_section->s_vaddr = vaddr;
+      lit4_section->s_paddr = vaddr;
+      lit4_section->s_size = 0;
+      lit4_section->s_scnptr = scnptr;
+    }
+  if (sdata_section != NULL)
+    {
+      sdata_section->s_vaddr = vaddr;
+      sdata_section->s_paddr = vaddr;
+      sdata_section->s_size = 0;
+      sdata_section->s_scnptr = scnptr;
+    }
+  if (sbss_section != NULL)
+    {
+      sbss_section->s_vaddr = vaddr;
+      sbss_section->s_paddr = vaddr;
+      sbss_section->s_size = 0;
+      sbss_section->s_scnptr = scnptr;
+    }
+  if (bss_section != NULL)
+    {
+      bss_section->s_vaddr = vaddr;
+      bss_section->s_paddr = vaddr;
+      bss_section->s_size = 0;
+      bss_section->s_scnptr = scnptr;
+    }
+
+  WRITE (new, TEXT_START, hdr.aout.tsize,
+	 "writing text section to %s", new_name);
+  WRITE (new, DATA_START, hdr.aout.dsize,
+	 "writing text section to %s", new_name);
+
+  SEEK (old, hdr.fhdr.f_symptr, "seeking to start of symbols in %s", a_name);
+  errno = EEOF;
+  nread = read (old, buffer, BUFSIZE);
+  if (nread < sizeof (HDRR)) fatal_unexec ("reading symbols from %s", a_name);
+#define symhdr ((pHDRR)buffer)
+  newsyms = hdr.aout.tsize + hdr.aout.dsize;
+  symrel = newsyms - hdr.fhdr.f_symptr;
+  hdr.fhdr.f_symptr = newsyms;
+  symhdr->cbLineOffset += symrel;
+  symhdr->cbDnOffset += symrel;
+  symhdr->cbPdOffset += symrel;
+  symhdr->cbSymOffset += symrel;
+  symhdr->cbOptOffset += symrel;
+  symhdr->cbAuxOffset += symrel;
+  symhdr->cbSsOffset += symrel;
+  symhdr->cbSsExtOffset += symrel;
+  symhdr->cbFdOffset += symrel;
+  symhdr->cbRfdOffset += symrel;
+  symhdr->cbExtOffset += symrel;
+#undef symhdr
+  do
+    {
+      if (write (new, buffer, nread) != nread)
+	fatal_unexec ("writing symbols to %s", new_name);
+      nread = read (old, buffer, BUFSIZE);
+      if (nread < 0) fatal_unexec ("reading symbols from %s", a_name);
+#undef BUFSIZE
+    } while (nread != 0);
+
+  SEEK (new, 0, "seeking to start of header in %s", new_name);
+  WRITE (new, &hdr, sizeof (hdr),
+	 "writing header of %s", new_name);
+
+  close (old);
+  close (new);
+  mark_x (new_name);
+}
+
+/*
+ * mark_x
+ *
+ * After succesfully building the new a.out, mark it executable
+ */
+
+static
+mark_x (name)
+     char *name;
+{
+  struct stat sbuf;
+  int um = umask (777);
+  umask (um);
+  if (stat (name, &sbuf) < 0)
+    fatal_unexec ("getting protection on %s", name);
+  sbuf.st_mode |= 0111 & ~um;
+  if (chmod (name, sbuf.st_mode) < 0)
+    fatal_unexec ("setting protection on %s", name);
+}
+
+static void
+fatal_unexec (s, va_alist)
+     va_dcl
+{
+  va_list ap;
+  if (errno == EEOF)
+    fputs ("unexec: unexpected end of file, ", stderr);
+  else if (errno < sys_nerr)
+    fprintf (stderr, "unexec: %s, ", sys_errlist[errno]);
+  else
+    fprintf (stderr, "unexec: error code %d, ", errno);
+  va_start (ap);
+  _doprnt (s, ap, stderr);
+  fputs (".\n", stderr);
+  exit (1);
+}