[Emacs-diffs] Changes to emacs/src/unexalpha.c [EMACS_21_1_RC]

[Dave Love]

Index: emacs/src/unexalpha.c
diff -c /dev/null emacs/src/unexalpha.c:1.15.16.1
*** /dev/null   Wed Sep 17 09:21:14 2003
--- emacs/src/unexalpha.c       Wed Sep 17 09:21:14 2003
***************
*** 0 ****
--- 1,542 ----
+ /* Unexec for DEC alpha.  address@hidden (Rainer Schoepf).
+ 
+    Copyright (C) 1994, 2000 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, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA.  */
+ 
+ 
+ #include <config.h>
+ #include <sys/types.h>
+ #include <sys/file.h>
+ #include <sys/stat.h>
+ #include <sys/mman.h>
+ #include <stdio.h>
+ #include <errno.h>
+ #ifdef HAVE_STRING_H
+ #include <string.h>
+ #endif
+ #if !defined (__NetBSD__) && !defined (__OpenBSD__)
+ #include <filehdr.h>
+ #include <aouthdr.h>
+ #include <scnhdr.h>
+ #include <syms.h>
+ #ifndef __linux__
+ # include <reloc.h>
+ # include <elf_abi.h>
+ #endif
+ #else /* __NetBSD__ or __OpenBSD__ */
+ /*
+  * NetBSD/Alpha does not have 'normal' user-land ECOFF support because
+  * there's no desire to support ECOFF as the executable format in the
+  * long term.
+  */
+ #include <sys/exec_ecoff.h>
+ 
+ /* Structures, constants, etc., that NetBSD defines strangely. */
+ #define       filehdr         ecoff_filehdr
+ #define       aouthdr         ecoff_aouthdr
+ #define       scnhdr          ecoff_scnhdr
+ #define       HDRR            struct ecoff_symhdr
+ #define       pHDRR           HDRR *
+ #define       cbHDRR          sizeof(HDRR)
+ #ifdef __OpenBSD__
+ #define       ALPHAMAGIC      ECOFF_MAGIC_NATIVE_ALPHA
+ #else
+ #define       ALPHAMAGIC      ECOFF_MAGIC_NETBSD_ALPHA
+ #endif
+ #define       ZMAGIC          ECOFF_ZMAGIC
+ 
+ /* Misc. constants that NetBSD doesn't define at all. */
+ #define       ALPHAUMAGIC     0617
+ #define       _MIPS_NSCNS_MAX 35
+ #define       STYP_TEXT       0x00000020
+ #define       STYP_DATA       0x00000040
+ #define       STYP_BSS        0x00000080
+ #define       STYP_RDATA      0x00000100
+ #define       STYP_SDATA      0x00000200
+ #define       STYP_SBSS       0x00000400
+ #define       STYP_INIT       0x80000000
+ #define       _TEXT           ".text"
+ #define       _DATA           ".data"
+ #define       _BSS            ".bss"
+ #define       _INIT           ".init"
+ #define       _RDATA          ".rdata"
+ #define       _SDATA          ".sdata"
+ #define       _SBSS           ".sbss"
+ #endif /* __NetBSD__ || __OpenBSD__ */
+ 
+ static void fatal_unexec __P ((char *, char *));
+ static void mark_x __P ((char *));
+ 
+ static void update_dynamic_symbols __P ((char *, char *, int, struct 
aouthdr));
+ 
+ #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);
+ 
+ #ifdef HAVE_UNISTD_H
+ #include <unistd.h>
+ #else
+ void *sbrk ();
+ #endif
+ 
+ #define EEOF -1
+ 
+ static struct scnhdr *text_section;
+ static struct scnhdr *rel_dyn_section;
+ static struct scnhdr *dynstr_section;
+ static struct scnhdr *dynsym_section;
+ static struct scnhdr *init_section;
+ static struct scnhdr *finit_section;
+ static struct scnhdr *rdata_section;
+ static struct scnhdr *rconst_section;
+ static struct scnhdr *data_section;
+ static struct scnhdr *pdata_section;
+ static struct scnhdr *xdata_section;
+ static struct scnhdr *got_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;
+ 
+ static struct scnhdr old_data_scnhdr;
+ 
+ static unsigned long Brk;
+ 
+ struct headers {
+     struct filehdr fhdr;
+     struct aouthdr aout;
+     struct scnhdr section[_MIPS_NSCNS_MAX];
+ };
+ 
+ 
+ 
+ /* Define name of label for entry point for the dumped executable.  */
+ 
+ #ifndef DEFAULT_ENTRY_ADDRESS
+ #define DEFAULT_ENTRY_ADDRESS __start
+ #endif
+ 
+ void
+ unexec (new_name, a_name, data_start, bss_start, entry_address)
+      char *new_name, *a_name;
+      unsigned long data_start, bss_start, entry_address;
+ {
+   int new, old;
+   char * oldptr;
+   struct headers ohdr, nhdr;
+   struct stat stat;
+   long pagesize, brk;
+   long newsyms, symrel;
+   int nread;
+   int i;
+   long vaddr, scnptr;
+ #define BUFSIZE 8192
+   char buffer[BUFSIZE];
+ 
+   if ((old = open (a_name, O_RDONLY)) < 0)
+     fatal_unexec ("opening %s", a_name);
+ 
+   new = creat (new_name, 0666);
+   if (new < 0) fatal_unexec ("creating %s", new_name);
+ 
+   if ((fstat (old, &stat) == -1))
+     fatal_unexec ("fstat %s", a_name);
+ 
+   oldptr = (char *)mmap (0, stat.st_size, PROT_READ, MAP_FILE|MAP_SHARED, 
old, 0);
+ 
+   if (oldptr == (char *)-1)
+     fatal_unexec ("mmap %s", a_name);
+ 
+   close (old);
+ 
+   /* This is a copy of the a.out header of the original executable */
+ 
+   ohdr = (*(struct headers *)oldptr);
+ 
+   /* This is where we build the new header from the in-memory copy */
+ 
+   nhdr = *((struct headers *)TEXT_START);
+ 
+   /* First do some consistency checks */
+ 
+   if (nhdr.fhdr.f_magic != ALPHAMAGIC
+       && nhdr.fhdr.f_magic != ALPHAUMAGIC)
+     {
+       fprintf (stderr, "unexec: input file magic number is %x, not %x or 
%x.\n",
+              nhdr.fhdr.f_magic, ALPHAMAGIC, ALPHAUMAGIC);
+       exit (1);
+     }
+ 
+   if (nhdr.fhdr.f_opthdr != sizeof (nhdr.aout))
+     {
+       fprintf (stderr, "unexec: input a.out header is %d bytes, not %d.\n",
+              nhdr.fhdr.f_opthdr, (int)sizeof (nhdr.aout));
+       exit (1);
+     }
+   if (nhdr.aout.magic != ZMAGIC)
+     {
+       fprintf (stderr, "unexec: input file a.out magic number is %o, not 
%o.\n",
+              nhdr.aout.magic, ZMAGIC);
+       exit (1);
+     }
+ 
+ 
+   /* Now check the existence of certain header section and grab
+      their addresses. */
+ 
+ #define CHECK_SCNHDR(ptr, name, flags)                                        
\
+   ptr = NULL;                                                         \
+   for (i = 0; i < nhdr.fhdr.f_nscns && !ptr; i++)                     \
+     if (strncmp (nhdr.section[i].s_name, name, 8) == 0)                       
\
+       {                                                                       
\
+       if (nhdr.section[i].s_flags != flags)                           \
+         fprintf (stderr, "unexec: %x flags (%x expected) in %s section.\n", \
+                  nhdr.section[i].s_flags, flags, name);               \
+       ptr = nhdr.section + i;                                         \
+       }                                                                       
\
+ 
+   CHECK_SCNHDR (text_section,  _TEXT,  STYP_TEXT);
+   CHECK_SCNHDR (init_section,  _INIT,  STYP_INIT);
+ #ifdef _REL_DYN
+   CHECK_SCNHDR (rel_dyn_section, _REL_DYN,  STYP_REL_DYN);
+ #endif /* _REL_DYN */
+ #ifdef _DYNSYM
+   CHECK_SCNHDR (dynsym_section, _DYNSYM,  STYP_DYNSYM);
+ #endif /* _REL_DYN */
+ #ifdef _DYNSTR
+   CHECK_SCNHDR (dynstr_section, _DYNSTR,  STYP_DYNSTR);
+ #endif /* _REL_DYN */
+ #ifdef _FINI
+   CHECK_SCNHDR (finit_section, _FINI,  STYP_FINI);
+ #endif /* _FINI */
+   CHECK_SCNHDR (rdata_section, _RDATA, STYP_RDATA);
+ #ifdef _RCONST
+   CHECK_SCNHDR (rconst_section, _RCONST, STYP_RCONST);
+ #endif
+ #ifdef _PDATA
+   CHECK_SCNHDR (pdata_section, _PDATA, STYP_PDATA);
+ #endif /* _PDATA */
+ #ifdef _GOT
+   CHECK_SCNHDR (got_section,   _GOT,   STYP_GOT);
+ #endif /* _GOT */
+   CHECK_SCNHDR (data_section,  _DATA,  STYP_DATA);
+ #ifdef _XDATA
+   CHECK_SCNHDR (xdata_section, _XDATA, STYP_XDATA);
+ #endif /* _XDATA */
+ #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);
+ 
+ 
+   pagesize = getpagesize ();
+   brk = (((long) (sbrk (0))) + pagesize - 1) & (-pagesize);
+ 
+   /* Remember the current break */
+ 
+   Brk = brk;
+ 
+   bcopy (data_section, &old_data_scnhdr, sizeof (old_data_scnhdr));
+ 
+   nhdr.aout.dsize = brk - DATA_START;
+   nhdr.aout.bsize = 0;
+   if (entry_address == 0)
+     {
+       extern DEFAULT_ENTRY_ADDRESS ();
+       nhdr.aout.entry = (unsigned long)DEFAULT_ENTRY_ADDRESS;
+     }
+   else
+     nhdr.aout.entry = entry_address;
+ 
+   nhdr.aout.bss_start = nhdr.aout.data_start + nhdr.aout.dsize;
+ 
+   if (rdata_section != NULL)
+     {
+       rdata_section->s_size = data_start - DATA_START;
+ 
+       /* Adjust start and virtual addresses of rdata_section, too.  */
+       rdata_section->s_vaddr = DATA_START;
+       rdata_section->s_paddr = DATA_START;
+       rdata_section->s_scnptr = text_section->s_scnptr + nhdr.aout.tsize;
+     }
+ 
+   data_section->s_vaddr = data_start;
+   data_section->s_paddr = data_start;
+   data_section->s_size = brk - data_start;
+ 
+   if (rdata_section != NULL)
+     {
+       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;
+     }
+ #ifdef _XDATA
+   if (xdata_section != NULL)
+     {
+       xdata_section->s_vaddr = vaddr;
+       xdata_section->s_paddr = vaddr;
+       xdata_section->s_size = 0;
+       xdata_section->s_scnptr = scnptr;
+     }
+ #endif
+ #ifdef _GOT
+   if (got_section != NULL)
+     {
+       bcopy (got_section, buffer, sizeof (struct scnhdr));
+ 
+       got_section->s_vaddr = vaddr;
+       got_section->s_paddr = vaddr;
+       got_section->s_size = 0;
+       got_section->s_scnptr = scnptr;
+     }
+ #endif /*_GOT */
+   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, (char *)TEXT_START, nhdr.aout.tsize,
+        "writing text section to %s", new_name);
+   WRITE (new, (char *)DATA_START, nhdr.aout.dsize,
+        "writing data section to %s", new_name);
+ 
+ #ifdef _GOT
+ #define old_got_section ((struct scnhdr *)buffer)
+ 
+   if (got_section != NULL)
+     {
+       SEEK (new, old_got_section->s_scnptr,
+           "seeking to start of got_section in %s", new_name);
+       WRITE (new, oldptr + old_got_section->s_scnptr, old_got_section->s_size,
+            "writing new got_section of %s", new_name);
+       SEEK (new, nhdr.aout.tsize + nhdr.aout.dsize,
+           "seeking to end of data section of %s", new_name);
+     }
+ 
+ #undef old_got_section
+ #endif
+ 
+   /*
+    * Construct new symbol table header
+    */
+ 
+   bcopy (oldptr + nhdr.fhdr.f_symptr, buffer, cbHDRR);
+ 
+ #define symhdr ((pHDRR)buffer)
+   newsyms = nhdr.aout.tsize + nhdr.aout.dsize;
+   symrel = newsyms - nhdr.fhdr.f_symptr;
+   nhdr.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;
+ 
+   WRITE (new, buffer, cbHDRR, "writing symbol table header of %s", new_name);
+ 
+   /*
+    * Copy the symbol table and line numbers
+    */
+   WRITE (new, oldptr + ohdr.fhdr.f_symptr + cbHDRR,
+        stat.st_size - ohdr.fhdr.f_symptr - cbHDRR,
+        "writing symbol table of %s", new_name);
+ 
+ #ifdef _REL_DYN
+   if (rel_dyn_section)
+     update_dynamic_symbols (oldptr, new_name, new, nhdr.aout);
+ #endif
+ 
+ #undef symhdr
+ 
+   SEEK (new, 0, "seeking to start of header in %s", new_name);
+   WRITE (new, &nhdr, sizeof (nhdr),
+        "writing header of %s", new_name);
+ 
+   close (old);
+   close (new);
+   mark_x (new_name);
+ }
+ 
+ 
+ static void
+ update_dynamic_symbols (old, new_name, new, aout)
+      char *old;                       /* Pointer to old executable */
+      char *new_name;            /* Name of new executable */
+      int new;                 /* File descriptor for new executable */
+      struct aouthdr aout;     /* a.out info from the file header */
+ {
+ #if !defined (__linux__) && !defined (__NetBSD__) && !defined (__OpenBSD__)
+ 
+   typedef struct dynrel_info {
+     char * addr;
+     unsigned type:8;
+     unsigned index:24;
+     unsigned info:8;
+     unsigned pad:8;
+   } dr_info;
+ 
+   int nsyms = rel_dyn_section->s_size / sizeof (struct dynrel_info);
+   int i;
+   dr_info * rd_base = (dr_info *) (old + rel_dyn_section->s_scnptr);
+   Elf32_Sym * ds_base = (Elf32_Sym *) (old + dynsym_section->s_scnptr);
+ 
+   for (i = 0; i < nsyms; i++) {
+     register Elf32_Sym x;
+ 
+     if (rd_base[i].index == 0)
+       continue;
+ 
+     x = ds_base[rd_base[i].index];
+ 
+ #if 0
+       fprintf (stderr, "Object inspected: %s, addr = %lx, shndx = %x",
+              old + dynstr_section->s_scnptr + x.st_name, rd_base[i].addr, 
x.st_shndx);
+ #endif
+ 
+ 
+     if ((ELF32_ST_BIND (x.st_info) == STB_GLOBAL)
+       && (x.st_shndx == 0)
+       /* && (x.st_value == NULL) */
+       ) {
+       /* OK, this is probably a reference to an object in a shared
+        library, so copy the old value. This is done in several steps:
+        1. reladdr is the address of the location in question relative to
+             the start of the data section,
+          2. oldref is the addr is the mapped in temacs executable,
+          3. newref is the address of the location in question in the
+             undumped executable,
+          4. len is the size of the object reference in bytes --
+             currently only 4 (long) and 8 (quad) are supported.
+           */
+       register unsigned long reladdr = (long)rd_base[i].addr - 
old_data_scnhdr.s_vaddr;
+       char * oldref = old + old_data_scnhdr.s_scnptr + reladdr;
+       unsigned long newref = aout.tsize + reladdr;
+       int len;
+ 
+ #if 0
+       fprintf (stderr, "...relocated\n");
+ #endif
+ 
+       if (rd_base[i].type == R_REFLONG) 
+       len = 4;
+       else if (rd_base[i].type == R_REFQUAD) 
+       len = 8;
+       else
+       fatal_unexec ("unrecognized relocation type in .dyn.rel section (symbol 
#%d)", i);
+ 
+       SEEK (new, newref, "seeking to dynamic symbol in %s", new_name);
+       WRITE (new, oldref, len, "writing old dynrel info in %s", new_name);
+     }
+ 
+ #if 0
+     else
+       fprintf (stderr, "...not relocated\n");
+ #endif
+ 
+   }
+ 
+ #endif /* not __linux__ and not __NetBSD__ and not __OpenBSD__ */
+ }
+ 
+ 
+ /*
+  * mark_x
+  *
+  * After successfully building the new a.out, mark it executable
+  */
+ 
+ static void
+ 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, arg)
+      char *s;
+      char *arg;
+ {
+   if (errno == EEOF)
+     fputs ("unexec: unexpected end of file, ", stderr);
+   else
+     fprintf (stderr, "unexec: %s, ", strerror (errno));
+   fprintf (stderr, s, arg);
+   fputs (".\n", stderr);
+   exit (1);
+ }