Shamusworld >> Repos - rmac/blob - object.c

   1 //
   2 // RMAC - Reboot's Macro Assembler for the Atari Jaguar Console System
   3 // OBJECT.C - Writing Object Files
   4 // Copyright (C) 199x Landon Dyer, 2011 Reboot and Friends
   5 // RMAC derived from MADMAC v1.07 Written by Landon Dyer, 1986
   6 // Source Utilised with the Kind Permission of Landon Dyer
   7 //
   8
   9 #include "object.h"
  10 #include "sect.h"
  11 #include "symbol.h"
  12 #include "mark.h"
  13 #include "error.h"
  14 #include "riscasm.h"
  15
  16 LONG symsize = 0;                                                       // Size of BSD symbol table
  17 LONG strindx = 0x00000004;                                      // BSD string table index
  18 char * strtable;                                                        // Pointer to the symbol string table
  19 char * objimage;                                                        // Global object image pointer
  20
  21
  22 //
  23 // Add an entry to the BSD symbol table
  24 //
  25 char * constr_bsdsymtab(char * buf, SYM * sym, int globflag)
  26 {
  27         LONG z;                                                                 // Scratch long
  28         WORD w1;                                                                // Scratch word
  29         int w2;                                                                 // Scratch long
  30
  31         chptr = buf;                                                    // Point to buffer for deposit longs
  32         D_long(strindx);                                                // Deposit the symbol string index
  33
  34         w1 = sym->sattr;                                                // Obtain symbol attribute
  35         w2 = sym->sattre;
  36         z = 0;                                                                  // Initialise resulting symbol flags
  37
  38         if (w1 & EQUATED)
  39         {
  40                 z = 0x02000000;                                         // Set equated flag
  41         }
  42         else
  43         {
  44                 switch (w1 & TDB)
  45                 {
  46                 case TEXT: z = 0x04000000; break;       // Set TEXT segment flag
  47                 case DATA: z = 0x06000000; break;       // Set DATA segment flag
  48                 case BSS : z = 0x08000000; break;       // Set BSS segment flag
  49                 }
  50         }
  51
  52         if (globflag)
  53                 z |= 0x01000000;                                        // Set global flag if requested
  54
  55         D_long(z);                                                              // Deposit symbol attribute
  56
  57         z = sym->svalue;                                                // Obtain symbol value
  58         w1 &= DATA | BSS;                                               // Determine DATA or BSS flag
  59
  60         if (w1)
  61                 z += sect[TEXT].sloc;                           // If DATA or BSS add TEXT segment size
  62
  63         if (w1 & BSS)
  64                 z += sect[DATA].sloc;                           // If BSS add DATA segment size
  65
  66         D_long(z);                                                              // Deposit symbol value
  67
  68         strcpy(strtable + strindx, sym->sname);
  69
  70         strindx += strlen(sym->sname) + 1;              // Incr string index incl null terminate
  71         buf += 12;                                                              // Increment buffer to next record
  72         symsize += 12;                                                  // Increment symbol table size
  73
  74         return buf;
  75 }
  76
  77
  78 //
  79 // Generate object file
  80 //
  81 int object(WORD fd)
  82 {
  83         LONG t;                                                                 // Scratch long
  84         LONG tds;                                                               // TEXT & DATA segment size
  85         int i;                                                                  // Temporary int
  86         CHUNK * cp;                                                             // Chunk (for gather)
  87         char * buf;                                                             // Scratch area
  88         char * p;                                                               // Temporary ptr
  89         LONG ssize;                                                             // Size of symbols
  90         LONG trsize, drsize;                                    // Size of relocations
  91
  92         // Write requested object file...
  93         switch (obj_format)
  94         {
  95         case BSD:
  96                 ssize = ((LONG)sy_assign(NULL, NULL));          // Assign index numbers to the symbols
  97                 tds = sect[TEXT].sloc + sect[DATA].sloc;        // Get size of TEXT and DATA segment
  98                 buf = malloc(0x600000);                                         // Allocate 6mb object file image memory
  99
 100                 if (buf == NULL)
 101                 {
 102                         error("cannot allocate object file memory (in BSD mode)");
 103                         return ERROR;
 104                 }
 105
 106                 memset(buf, 0, 0x600000);                                       // Reset allocated memory
 107                 objimage = buf;                                                         // Set global object image pointer
 108                 strtable = malloc(0x200000);                            // Allocate 2mb scratch buffer
 109
 110                 if (strtable == NULL)
 111                 {
 112                         error("cannot allocate string table memory (in BSD mode)");
 113                         return ERROR;
 114                 }
 115
 116                 memset(strtable, 0, 0x200000);                          // Reset allocated memory
 117
 118                 // Build object file header
 119                 chptr = buf;                                                            // Base of header
 120                 t = 0x00000107;
 121                 D_long(t);                                                                      // Magic number
 122                 t = sect[TEXT].sloc;                                            // TEXT size
 123                 D_long(t);
 124                 t = sect[DATA].sloc;                                            // DATA size
 125                 D_long(t);
 126                 t = sect[BSS].sloc;                                                     // BSS size
 127                 D_long(t);
 128                 t = 0x00000000;
 129                 D_long(t);                                                                      // Symbol size
 130                 D_long(t);                                                                      // First entry (0L)
 131                 D_long(t);                                                                      // TEXT relocation size
 132                 D_long(t);                                                                      // BSD relocation size
 133
 134                 // Construct TEXT and DATA segments (without relocation changes)
 135                 p = buf + BSDHDRSIZE;
 136
 137                 for(i=TEXT; i<=DATA; ++i)
 138                 {
 139                         for(cp=sect[i].sfcode; cp!=NULL; cp=cp->chnext)
 140                         {
 141                                 copy(p, cp->chptr, cp->ch_size);
 142                                 p += cp->ch_size;
 143                         }
 144                 }
 145
 146                 // Do relocation tables (and make changes to segment data)
 147                 p = buf + (BSDHDRSIZE + tds);                           // Move obj image ptr to reloc info
 148                 trsize = bsdmarkimg(p, tds, sect[TEXT].sloc, TEXT);// Do TEXT relocation table
 149                 chptr = buf + 24;                                                       // Point to relocation hdr entry
 150                 D_long(trsize);                                                         // Write the relocation table size
 151                 p = buf + (BSDHDRSIZE + tds + trsize);          // Move obj image ptr to reloc info
 152                 drsize = bsdmarkimg(p, tds, sect[TEXT].sloc, DATA);// Do DATA relocation table
 153                 chptr = buf + 28;                                                       // Point to relocation hdr entry
 154                 D_long(drsize);                                                         // Write the relocation table size
 155
 156                 p = buf + (BSDHDRSIZE + tds + trsize + drsize);// Point to start of symbol table
 157                 sy_assign(p, constr_bsdsymtab);                         // Build symbol and string tables
 158                 chptr = buf + 16;                                                       // Point to sym table size hdr entry
 159                 D_long(symsize);                                                        // Write the symbol table size
 160
 161                 // Point to string table
 162                 p = buf + (BSDHDRSIZE + tds + trsize + drsize + symsize);
 163
 164                 memcpy(p, strtable, strindx);                           // Copy string table to object image
 165
 166                 if (buf)
 167                         free(strtable);                                                 // Free allocated memory
 168
 169                 chptr = p;                                                                      // Point to string table size long
 170                 D_long(strindx);                                                        // Write string table size
 171
 172                 // Write the BSD object file from the object image buffer
 173                 write(fd, buf, BSDHDRSIZE + tds + trsize + drsize + symsize + strindx + 4);
 174
 175                 if (buf)
 176                         free(buf);                                                              // Free allocated memory
 177
 178                 break;
 179         }
 180
 181         return 0;
 182 }