src/unexapollo.c

   1 /* unexapollo.c -- COFF File UNEXEC for GNU Emacs on Apollo SR10.x
   2    Copyright (C) 1988, 1994, 2002, 2003, 2004,
   3                  2005 Free Software Foundation, Inc.
   4
   5 This file is part of GNU Emacs.
   6
   7 GNU Emacs is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU Emacs is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Emacs; see the file COPYING.  If not, write to
  19 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  20 Boston, MA 02110-1301, USA.  */
  21
  22 /* Written by Leonard N. Zubkoff.  */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #include <fcntl.h>
  29
  30
  31 #include <a.out.h>
  32 #include <sys/file.h>
  33 #include <apollo/base.h>
  34 #include <apollo/ios.h>
  35 #include <apollo/type_uids.h>
  36 #include <apollo/dst.h>
  37
  38
  39 #define DST_RECORD_HDR_SIZE     2
  40 #define LONG_ALIGN(X)           (((X)+3)&(~3))
  41
  42
  43 void
  44 unexec (target_file_name, source_file_name)
  45      char *target_file_name, *source_file_name;
  46 {
  47   struct filehdr file_header;
  48   struct aouthdr domain_header;
  49   struct scnhdr *section, *sections, *sections_limit;
  50   struct scnhdr *first_data_section, *last_data_section;
  51   struct scnhdr *rwdi_section, *blocks_section;
  52   struct reloc reloc_entry;
  53   unsigned long data_size, old_data_section_size, source_file_offset_past_rwdi;
  54   unsigned char buffer[4096];
  55   long delta_before_rwdi, delta_after_rwdi, byte_count;
  56   long first_changed_vaddr, old_rwdi_vaddr, i;
  57   ios_$id_t target_file, source_file;
  58   status_$t status;
  59   /* Open the Source File. */
  60   if ((source_file = open (source_file_name, O_RDONLY)) < 0)
  61     error ("cannot open source file for input");
  62   /* Read the File Header. */
  63   if (read (source_file, &file_header, sizeof (file_header)) != sizeof (file_header))
  64     error ("cannot read file header");
  65   \f
  66   /* Read the Domain Header. */
  67   if (read (source_file, &domain_header, sizeof (domain_header))
  68       != sizeof (domain_header))
  69     error ("cannot read domain header");
  70   /* Read the Section Headers. */
  71   sections =
  72     (struct scnhdr *) malloc (file_header.f_nscns*sizeof (struct scnhdr));
  73   if (sections == (struct scnhdr *) 0)
  74     error ("cannot allocate section header storage");
  75   sections_limit = sections + file_header.f_nscns;
  76   if (read (source_file, sections, file_header.f_nscns*sizeof (struct scnhdr))
  77       != file_header.f_nscns*sizeof (struct scnhdr))
  78     error ("cannot read section headers");
  79   /* Compute the new Size of the Data Section. */
  80   data_size = sbrk (0) - domain_header.data_start;
  81   delta_before_rwdi = delta_after_rwdi = data_size - domain_header.dsize;
  82   old_rwdi_vaddr = 0;
  83   /* Find and Deallocate the .rwdi Section Information. */
  84   for (rwdi_section = sections; rwdi_section != sections_limit; rwdi_section++)
  85     if (strcmp (rwdi_section->s_name, ".rwdi") == 0)
  86       {
  87         /* If there are relocation entries, we cannot "unrelocate" them. */
  88         if (rwdi_section->s_nreloc > 0)
  89           error (".rwdi section needs relocation - cannot dump Emacs");
  90         delta_after_rwdi = delta_before_rwdi - rwdi_section->s_size;
  91         old_rwdi_vaddr = rwdi_section->s_vaddr;
  92         rwdi_section->s_paddr = 0;
  93         rwdi_section->s_vaddr = 0;
  94         rwdi_section->s_scnptr = 0;
  95         rwdi_section->s_size = 0;
  96         source_file_offset_past_rwdi = (rwdi_section+1)->s_scnptr;
  97         break;
  98       }
  99   /* Skip over the Text Section Headers. */
 100   for (section = sections; (section->s_flags & STYP_TEXT) != 0; section++) ;
 101   /*
 102     Find the First and Last Data Sections and Fixup
 103     Section Header Relocation Pointers.
 104     */
 105   first_data_section = last_data_section = (struct scnhdr *) 0;
 106   for (; section != sections_limit; section++)
 107     {
 108       if ((section->s_flags & STYP_DATA) != 0)
 109         {
 110           if (first_data_section == (struct scnhdr *) 0)
 111             first_data_section = section;
 112           last_data_section = section;
 113         }
 114       if (section->s_relptr != 0)
 115         section->s_relptr += delta_after_rwdi;
 116     }
 117   /* Increment the Size of the Last Data Section. */
 118   old_data_section_size = last_data_section->s_size;
 119   last_data_section->s_size += delta_before_rwdi;
 120   \f
 121   /* Update the File Header and Domain Header. */
 122   file_header.f_symptr += delta_after_rwdi;
 123   domain_header.dsize = data_size;
 124   domain_header.bsize = 0;
 125   /* Skip over subsequent Bss Section Headers. */
 126   for (section = last_data_section+1;
 127        (section->s_flags & STYP_BSS) != 0; section++) ;
 128   /* Update the remaining Section Headers. */
 129   blocks_section = (struct scnhdr *) 0;
 130   first_changed_vaddr = 0;
 131   for (; section != sections_limit; section++)
 132     {
 133       long delta = (section < rwdi_section ? delta_before_rwdi : delta_after_rwdi);
 134       if (section->s_paddr != 0)
 135         section->s_paddr += delta;
 136       if (section->s_vaddr != 0)
 137         {
 138           if (first_changed_vaddr == 0)
 139             first_changed_vaddr = section->s_vaddr;
 140           section->s_vaddr += delta;
 141         }
 142       if (section->s_scnptr != 0)
 143         section->s_scnptr += delta;
 144       if (strcmp (section->s_name, ".blocks") == 0)
 145         blocks_section = section;
 146       else if (strcmp (section->s_name, ".sri") == 0 &&
 147                domain_header.o_sri != 0)
 148         domain_header.o_sri += delta;
 149       else if (strcmp (section->s_name, ".inlib") == 0 &&
 150                domain_header.o_inlib != 0)
 151         domain_header.o_inlib += delta;
 152     }
 153   /* Open the Target File. */
 154   ios_$create (target_file_name, strlen (target_file_name), coff_$uid,
 155                ios_$recreate_mode, ios_$write_opt, &target_file, &status);
 156   if (status.all != status_$ok)
 157     error ("cannot open target file for output");
 158   /* Write the File Header. */
 159   if (write (target_file, &file_header, sizeof (file_header)) != sizeof (file_header))
 160     error ("cannot write file header");
 161   /* Write the Domain Header. */
 162   if (write (target_file, &domain_header, sizeof (domain_header))
 163       != sizeof (domain_header))
 164     error ("cannot write domain header");
 165   /* Write the Section Headers. */
 166   if (write (target_file, sections, file_header.f_nscns*sizeof (struct scnhdr))
 167       != file_header.f_nscns*sizeof (struct scnhdr))
 168     error ("cannot write section headers");
 169   /* Copy the Allocated Sections. */
 170   for (section = sections; section != first_data_section; section++)
 171     if (section->s_scnptr != 0)
 172       CopyData (target_file, source_file, LONG_ALIGN(section->s_size));
 173   /* Write the Expanded Data Segment. */
 174   if (write (target_file, first_data_section->s_vaddr, data_size) != data_size)
 175     error ("cannot write new data section");
 176   \f
 177   /* Skip over the Last Data Section and Copy until the .rwdi Section. */
 178   if (lseek (source_file, last_data_section->s_scnptr
 179              +old_data_section_size, L_SET) == -1)
 180     error ("cannot seek past data section");
 181   for (section = last_data_section+1; section != rwdi_section; section++)
 182     if (section->s_scnptr != 0)
 183       CopyData (target_file, source_file, LONG_ALIGN(section->s_size));
 184   /* Skip over the .rwdi Section and Copy Remainder of Source File. */
 185   if (lseek (source_file, source_file_offset_past_rwdi, L_SET) == -1)
 186     error ("cannot seek past .rwdi section");
 187   while ((byte_count = read (source_file, buffer, sizeof (buffer))) > 0)
 188     if (write (target_file, buffer, byte_count) != byte_count)
 189       error ("cannot write data");
 190   /* Unrelocate .data references to Global Symbols. */
 191   for (section = first_data_section; section <= last_data_section; section++)
 192     for (i = 0; i < section->s_nreloc; i++)
 193       {
 194         if  (lseek (source_file, section->s_relptr
 195                     +i*sizeof (struct reloc)-delta_after_rwdi, L_SET) == -1)
 196           error ("cannot seek to relocation info");
 197         if (read (source_file, &reloc_entry, sizeof (reloc_entry))
 198             != sizeof (reloc_entry))
 199           error ("cannot read reloc entry");
 200         if (lseek (source_file, reloc_entry.r_vaddr-section->s_vaddr
 201                    +section->s_scnptr, L_SET) == -1)
 202           error ("cannot seek to data element");
 203         if (lseek (target_file, reloc_entry.r_vaddr-section->s_vaddr
 204                    +section->s_scnptr, L_SET) == -1)
 205           error ("cannot seek to data element");
 206         if (read (source_file, buffer, 4) != 4)
 207           error ("cannot read data element");
 208         if (write (target_file, buffer, 4) != 4)
 209           error ("cannot write data element");
 210       }
 211   \f
 212   /* Correct virtual addresses in .blocks section. */
 213   if (blocks_section != (struct scnhdr *) 0)
 214     {
 215       dst_rec_t dst_record;
 216       dst_rec_comp_unit_t *comp_unit;
 217       unsigned short number_of_sections;
 218       unsigned long section_base;
 219       unsigned long section_offset = 0;
 220       /* Find section tables and update section base addresses. */
 221       while (section_offset < blocks_section->s_size)
 222         {
 223           if (lseek (target_file,
 224                      blocks_section->s_scnptr+section_offset, L_SET) == -1)
 225             error ("cannot seek to comp unit record");
 226           /* Handle pad records before the comp unit record. */
 227           if (read (target_file, &dst_record, DST_RECORD_HDR_SIZE)
 228               != DST_RECORD_HDR_SIZE)
 229             error ("cannot read dst record tag");
 230           if (dst_record.rec_type == dst_typ_pad)
 231             section_offset += DST_RECORD_HDR_SIZE;
 232           else if (dst_record.rec_type == dst_typ_comp_unit)
 233             {
 234               comp_unit = &dst_record.rec_data.comp_unit_;
 235               if  (read (target_file, comp_unit, sizeof (*comp_unit))
 236                    != sizeof (*comp_unit))
 237                 error ("cannot read comp unit record");
 238               if (lseek (target_file, blocks_section->s_scnptr
 239                          +section_offset
 240 #if dst_version_major == 1 && dst_version_minor < 4
 241                          +comp_unit->section_table
 242 #else
 243                          +comp_unit->section_table.rel_offset
 244 #endif
 245                          +DST_RECORD_HDR_SIZE,
 246                          L_SET) == -1)
 247                 error ("cannot seek to section table");
 248               if (read (target_file, &number_of_sections, sizeof (number_of_sections))
 249                   != sizeof (number_of_sections))
 250                 error ("cannot read section table size");
 251               for (i = 0; i < number_of_sections; i++)
 252                 {
 253                   if (read (target_file, &section_base, sizeof (section_base))
 254                       != sizeof (section_base))
 255                     error ("cannot read section base value");
 256                   if (section_base < first_changed_vaddr)
 257                     continue;
 258                   else if (section_base < old_rwdi_vaddr)
 259                     section_base += delta_before_rwdi;
 260                   else section_base += delta_after_rwdi;
 261                   if (lseek (target_file, -sizeof (section_base), L_INCR) == -1)
 262                     error ("cannot seek to section base value");
 263                   if (write (target_file, &section_base, sizeof (section_base))
 264                       != sizeof (section_base))
 265                     error ("cannot write section base");
 266                 }
 267               section_offset += comp_unit->data_size;
 268             }
 269           else error ("unexpected dst record type");
 270         }
 271     }
 272   \f
 273   if (close (source_file) == -1)
 274     error("cannot close source file");
 275   if (close (target_file) == -1)
 276     error ("cannot close target file");
 277 }
 278
 279
 280 static
 281 CopyData (target_file, source_file, total_byte_count)
 282      int target_file, source_file;
 283      long total_byte_count;
 284 {
 285   unsigned char buffer[4096];
 286   long byte_count;
 287   while (total_byte_count > 0)
 288     {
 289       if (total_byte_count > sizeof (buffer))
 290         byte_count = sizeof (buffer);
 291       else byte_count = total_byte_count;
 292       if (read (source_file, buffer, byte_count) != byte_count)
 293         error ("cannot read data");
 294       if (write (target_file, buffer, byte_count) != byte_count)
 295         error ("cannot write data");
 296       total_byte_count -= byte_count;
 297     }
 298 }
 299
 300 /* arch-tag: 783ebbdf-7d26-4df8-9469-17a1747dce96
 301    (do not change this comment) */