include/aout/adobe.h

   1 /* `a.out.adobe' differences from standard a.out files
   2
   3    Copyright 2001 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 2 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software
  17    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
  18
  19 #ifndef __A_OUT_ADOBE_H__
  20 #define __A_OUT_ADOBE_H__
  21
  22 #define BYTES_IN_WORD   4
  23
  24 /* Struct external_exec is the same.  */
  25
  26 /* This is the layout on disk of the 32-bit or 64-bit exec header. */
  27
  28 struct external_exec
  29 {
  30   bfd_byte e_info[4];           /* magic number and stuff               */
  31   bfd_byte e_text[BYTES_IN_WORD]; /* length of text section in bytes    */
  32   bfd_byte e_data[BYTES_IN_WORD]; /* length of data section in bytes    */
  33   bfd_byte e_bss[BYTES_IN_WORD]; /* length of bss area in bytes                 */
  34   bfd_byte e_syms[BYTES_IN_WORD]; /* length of symbol table in bytes    */
  35   bfd_byte e_entry[BYTES_IN_WORD]; /* start address                     */
  36   bfd_byte e_trsize[BYTES_IN_WORD]; /* length of text relocation info   */
  37   bfd_byte e_drsize[BYTES_IN_WORD]; /* length of data relocation info   */
  38 };
  39
  40 #define EXEC_BYTES_SIZE (4 + BYTES_IN_WORD * 7)
  41
  42 /* Magic numbers for a.out files */
  43
  44 #undef  ZMAGIC
  45 #define ZMAGIC  0xAD0BE         /* Cute, eh?  */
  46 #undef  OMAGIC
  47 #undef  NMAGIC
  48
  49 #define N_BADMAG(x)       ((x).a_info != ZMAGIC)
  50
  51 /* By default, segment size is constant.  But some machines override this
  52    to be a function of the a.out header (e.g. machine type).  */
  53 #ifndef N_SEGSIZE
  54 #define N_SEGSIZE(x)    SEGMENT_SIZE
  55 #endif
  56 #undef N_SEGSIZE   /* FIXMEXXXX */
  57
  58 /* Segment information for the a.out.Adobe format is specified after the
  59    file header.  It contains N segment descriptors, followed by one with
  60    a type of zero.
  61
  62    The actual text of the segments starts at N_TXTOFF in the file,
  63    regardless of how many or how few segment headers there are.  */
  64
  65 struct external_segdesc {
  66         unsigned char e_type[1];
  67         unsigned char e_size[3];
  68         unsigned char e_virtbase[4];
  69         unsigned char e_filebase[4];
  70 };
  71
  72 struct internal_segdesc {
  73         unsigned int    a_type:8;       /* Segment type N_TEXT, N_DATA, 0 */
  74         unsigned int    a_size:24;      /* Segment size */
  75         bfd_vma         a_virtbase;     /* Virtual address */
  76         unsigned int    a_filebase;     /* Base address in object file */
  77 };
  78
  79 #define N_TXTADDR(x) \
  80
  81 /* This is documented to be at 1024, but appears to really be at 2048.
  82    FIXME?!  */
  83 #define N_TXTOFF(x)     2048
  84
  85 #define N_TXTSIZE(x) ((x).a_text)
  86
  87 #define N_DATADDR(x)
  88
  89 #define N_BSSADDR(x)
  90
  91 /* Offsets of the various portions of the file after the text segment.  */
  92
  93 #define N_DATOFF(x)     ( N_TXTOFF(x) + N_TXTSIZE(x) )
  94 #define N_TRELOFF(x)    ( N_DATOFF(x) + (x).a_data )
  95 #define N_DRELOFF(x)    ( N_TRELOFF(x) + (x).a_trsize )
  96 #define N_SYMOFF(x)     ( N_DRELOFF(x) + (x).a_drsize )
  97 #define N_STROFF(x)     ( N_SYMOFF(x) + (x).a_syms )
  98 \f
  99 /* Symbols */
 100 struct external_nlist {
 101   bfd_byte e_strx[BYTES_IN_WORD];       /* index into string table of name */
 102   bfd_byte e_type[1];                   /* type of symbol */
 103   bfd_byte e_other[1];                  /* misc info (usually empty) */
 104   bfd_byte e_desc[2];                   /* description field */
 105   bfd_byte e_value[BYTES_IN_WORD];      /* value of symbol */
 106 };
 107
 108 #define EXTERNAL_NLIST_SIZE (BYTES_IN_WORD+4+BYTES_IN_WORD)
 109
 110 struct internal_nlist {
 111   unsigned long n_strx;                 /* index into string table of name */
 112   unsigned char n_type;                 /* type of symbol */
 113   unsigned char n_other;                /* misc info (usually empty) */
 114   unsigned short n_desc;                /* description field */
 115   bfd_vma n_value;                      /* value of symbol */
 116 };
 117
 118 /* The n_type field is the symbol type, containing:  */
 119
 120 #define N_UNDF  0       /* Undefined symbol */
 121 #define N_ABS   2       /* Absolute symbol -- defined at particular addr */
 122 #define N_TEXT  4       /* Text sym -- defined at offset in text seg */
 123 #define N_DATA  6       /* Data sym -- defined at offset in data seg */
 124 #define N_BSS   8       /* BSS  sym -- defined at offset in zero'd seg */
 125 #define N_COMM  0x12    /* Common symbol (visible after shared lib dynlink) */
 126 #define N_FN    0x1f    /* File name of .o file */
 127 #define N_FN_SEQ 0x0C   /* N_FN from Sequent compilers (sigh) */
 128 /* Note: N_EXT can only be usefully OR-ed with N_UNDF, N_ABS, N_TEXT,
 129    N_DATA, or N_BSS.  When the low-order bit of other types is set,
 130    (e.g. N_WARNING versus N_FN), they are two different types.  */
 131 #define N_EXT   1       /* External symbol (as opposed to local-to-this-file) */
 132 #define N_TYPE  0x1e
 133 #define N_STAB  0xe0    /* If any of these bits are on, it's a debug symbol */
 134
 135 #define N_INDR 0x0a
 136
 137 /* The following symbols refer to set elements.
 138    All the N_SET[ATDB] symbols with the same name form one set.
 139    Space is allocated for the set in the text section, and each set
 140    elements value is stored into one word of the space.
 141    The first word of the space is the length of the set (number of elements).
 142
 143    The address of the set is made into an N_SETV symbol
 144    whose name is the same as the name of the set.
 145    This symbol acts like a N_DATA global symbol
 146    in that it can satisfy undefined external references.  */
 147
 148 /* These appear as input to LD, in a .o file.  */
 149 #define N_SETA  0x14            /* Absolute set element symbol */
 150 #define N_SETT  0x16            /* Text set element symbol */
 151 #define N_SETD  0x18            /* Data set element symbol */
 152 #define N_SETB  0x1A            /* Bss set element symbol */
 153
 154 /* This is output from LD.  */
 155 #define N_SETV  0x1C            /* Pointer to set vector in data area.  */
 156
 157 /* Warning symbol. The text gives a warning message, the next symbol
 158    in the table will be undefined. When the symbol is referenced, the
 159    message is printed.  */
 160
 161 #define N_WARNING 0x1e
 162
 163 /* Relocations
 164
 165   There are two types of relocation flavours for a.out systems,
 166   standard and extended. The standard form is used on systems where the
 167   instruction has room for all the bits of an offset to the operand, whilst
 168   the extended form is used when an address operand has to be split over n
 169   instructions. Eg, on the 68k, each move instruction can reference
 170   the target with a displacement of 16 or 32 bits. On the sparc, move
 171   instructions use an offset of 14 bits, so the offset is stored in
 172   the reloc field, and the data in the section is ignored.
 173 */
 174
 175 /* This structure describes a single relocation to be performed.
 176    The text-relocation section of the file is a vector of these structures,
 177    all of which apply to the text section.
 178    Likewise, the data-relocation section applies to the data section.  */
 179
 180 struct reloc_std_external {
 181   bfd_byte r_address[BYTES_IN_WORD];    /* offset of of data to relocate */
 182   bfd_byte r_index[3];  /* symbol table index of symbol         */
 183   bfd_byte r_type[1];   /* relocation type                      */
 184 };
 185
 186 #define RELOC_STD_BITS_PCREL_BIG        0x80
 187 #define RELOC_STD_BITS_PCREL_LITTLE     0x01
 188
 189 #define RELOC_STD_BITS_LENGTH_BIG       0x60
 190 #define RELOC_STD_BITS_LENGTH_SH_BIG    5       /* To shift to units place */
 191 #define RELOC_STD_BITS_LENGTH_LITTLE    0x06
 192 #define RELOC_STD_BITS_LENGTH_SH_LITTLE 1
 193
 194 #define RELOC_STD_BITS_EXTERN_BIG       0x10
 195 #define RELOC_STD_BITS_EXTERN_LITTLE    0x08
 196
 197 #define RELOC_STD_BITS_BASEREL_BIG      0x08
 198 #define RELOC_STD_BITS_BASEREL_LITTLE   0x08
 199
 200 #define RELOC_STD_BITS_JMPTABLE_BIG     0x04
 201 #define RELOC_STD_BITS_JMPTABLE_LITTLE  0x04
 202
 203 #define RELOC_STD_BITS_RELATIVE_BIG     0x02
 204 #define RELOC_STD_BITS_RELATIVE_LITTLE  0x02
 205
 206 #define RELOC_STD_SIZE  (BYTES_IN_WORD + 3 + 1)         /* Bytes per relocation entry */
 207
 208 struct reloc_std_internal
 209 {
 210   bfd_vma r_address;            /* Address (within segment) to be relocated.  */
 211   /* The meaning of r_symbolnum depends on r_extern.  */
 212   unsigned int r_symbolnum:24;
 213   /* Nonzero means value is a pc-relative offset
 214      and it should be relocated for changes in its own address
 215      as well as for changes in the symbol or section specified.  */
 216   unsigned int r_pcrel:1;
 217   /* Length (as exponent of 2) of the field to be relocated.
 218      Thus, a value of 2 indicates 1<<2 bytes.  */
 219   unsigned int r_length:2;
 220   /* 1 => relocate with value of symbol.
 221      r_symbolnum is the index of the symbol
 222      in files the symbol table.
 223      0 => relocate with the address of a segment.
 224      r_symbolnum is N_TEXT, N_DATA, N_BSS or N_ABS
 225      (the N_EXT bit may be set also, but signifies nothing).  */
 226   unsigned int r_extern:1;
 227   /* The next three bits are for SunOS shared libraries, and seem to
 228      be undocumented.  */
 229   unsigned int r_baserel:1;     /* Linkage table relative */
 230   unsigned int r_jmptable:1;    /* pc-relative to jump table */
 231   unsigned int r_relative:1;    /* "relative relocation" */
 232   /* unused */
 233   unsigned int r_pad:1;         /* Padding -- set to zero */
 234 };
 235
 236
 237 /* EXTENDED RELOCS  */
 238
 239 struct reloc_ext_external {
 240   bfd_byte r_address[BYTES_IN_WORD];    /* offset of of data to relocate        */
 241   bfd_byte r_index[3];  /* symbol table index of symbol         */
 242   bfd_byte r_type[1];   /* relocation type                      */
 243   bfd_byte r_addend[BYTES_IN_WORD];     /* datum addend                         */
 244 };
 245
 246 #define RELOC_EXT_BITS_EXTERN_BIG       0x80
 247 #define RELOC_EXT_BITS_EXTERN_LITTLE    0x01
 248
 249 #define RELOC_EXT_BITS_TYPE_BIG         0x1F
 250 #define RELOC_EXT_BITS_TYPE_SH_BIG      0
 251 #define RELOC_EXT_BITS_TYPE_LITTLE      0xF8
 252 #define RELOC_EXT_BITS_TYPE_SH_LITTLE   3
 253
 254 /* Bytes per relocation entry */
 255 #define RELOC_EXT_SIZE  (BYTES_IN_WORD + 3 + 1 + BYTES_IN_WORD)
 256
 257 enum reloc_type
 258 {
 259   /* simple relocations */
 260   RELOC_8,                      /* data[0:7] = addend + sv              */
 261   RELOC_16,                     /* data[0:15] = addend + sv             */
 262   RELOC_32,                     /* data[0:31] = addend + sv             */
 263   /* pc-rel displacement */
 264   RELOC_DISP8,                  /* data[0:7] = addend - pc + sv         */
 265   RELOC_DISP16,                 /* data[0:15] = addend - pc + sv        */
 266   RELOC_DISP32,                 /* data[0:31] = addend - pc + sv        */
 267   /* Special */
 268   RELOC_WDISP30,                /* data[0:29] = (addend + sv - pc)>>2   */
 269   RELOC_WDISP22,                /* data[0:21] = (addend + sv - pc)>>2   */
 270   RELOC_HI22,                   /* data[0:21] = (addend + sv)>>10       */
 271   RELOC_22,                     /* data[0:21] = (addend + sv)           */
 272   RELOC_13,                     /* data[0:12] = (addend + sv)           */
 273   RELOC_LO10,                   /* data[0:9] = (addend + sv)            */
 274   RELOC_SFA_BASE,
 275   RELOC_SFA_OFF13,
 276   /* P.I.C. (base-relative) */
 277   RELOC_BASE10,                 /* Not sure - maybe we can do this the */
 278   RELOC_BASE13,                 /* right way now */
 279   RELOC_BASE22,
 280   /* for some sort of pc-rel P.I.C. (?) */
 281   RELOC_PC10,
 282   RELOC_PC22,
 283   /* P.I.C. jump table */
 284   RELOC_JMP_TBL,
 285   /* reputedly for shared libraries somehow */
 286   RELOC_SEGOFF16,
 287   RELOC_GLOB_DAT,
 288   RELOC_JMP_SLOT,
 289   RELOC_RELATIVE,
 290
 291   RELOC_11,
 292   RELOC_WDISP2_14,
 293   RELOC_WDISP19,
 294   RELOC_HHI22,                  /* data[0:21] = (addend + sv) >> 42     */
 295   RELOC_HLO10,                  /* data[0:9] = (addend + sv) >> 32      */
 296
 297   /* 29K relocation types */
 298   RELOC_JUMPTARG,
 299   RELOC_CONST,
 300   RELOC_CONSTH,
 301
 302   NO_RELOC
 303   };
 304
 305
 306 struct reloc_internal {
 307   bfd_vma r_address;            /* offset of of data to relocate        */
 308   long  r_index;                /* symbol table index of symbol         */
 309   enum reloc_type r_type;       /* relocation type                      */
 310   bfd_vma r_addend;             /* datum addend                         */
 311 };
 312
 313 #endif                          /* __A_OUT_ADOBE_H__ */