include/aout/adobe.h

   1 /* `a.out.adobe' differences from standard a.out files
   2
   3    Copyright (C) 2001-2018 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 3 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,
  18    MA 02110-1301, USA.  */
  19
  20 #ifndef __A_OUT_ADOBE_H__
  21 #define __A_OUT_ADOBE_H__
  22
  23 #define BYTES_IN_WORD   4
  24
  25 /* Struct external_exec is the same.  */
  26
  27 /* This is the layout on disk of the 32-bit or 64-bit exec header.  */
  28
  29 struct external_exec
  30 {
  31   bfd_byte e_info[4];               /* Magic number and stuff.  */
  32   bfd_byte e_text[BYTES_IN_WORD];   /* Length of text section in bytes.  */
  33   bfd_byte e_data[BYTES_IN_WORD];   /* Length of data section in bytes.  */
  34   bfd_byte e_bss[BYTES_IN_WORD];    /* Length of bss area in bytes.  */
  35   bfd_byte e_syms[BYTES_IN_WORD];   /* Length of symbol table in bytes.  */
  36   bfd_byte e_entry[BYTES_IN_WORD];  /* Start address.  */
  37   bfd_byte e_trsize[BYTES_IN_WORD]; /* Length of text relocation info.  */
  38   bfd_byte e_drsize[BYTES_IN_WORD]; /* Length of data relocation info.  */
  39 };
  40
  41 #define EXEC_BYTES_SIZE (4 + BYTES_IN_WORD * 7)
  42
  43 /* Magic numbers for a.out files.  */
  44
  45 #undef  ZMAGIC
  46 #define ZMAGIC  0xAD0BE         /* Cute, eh?  */
  47 #undef  OMAGIC
  48 #undef  NMAGIC
  49
  50 #define N_BADMAG(x)       ((x)->a_info != ZMAGIC)
  51
  52 /* By default, segment size is constant.  But some machines override this
  53    to be a function of the a.out header (e.g. machine type).  */
  54 #ifndef N_SEGSIZE
  55 #define N_SEGSIZE(x)    SEGMENT_SIZE
  56 #endif
  57 #undef N_SEGSIZE   /* FIXMEXXXX */
  58
  59 /* Segment information for the a.out.Adobe format is specified after the
  60    file header.  It contains N segment descriptors, followed by one with
  61    a type of zero.
  62
  63    The actual text of the segments starts at N_TXTOFF in the file,
  64    regardless of how many or how few segment headers there are.  */
  65
  66 struct external_segdesc
  67 {
  68   unsigned char e_type[1];
  69   unsigned char e_size[3];
  70   unsigned char e_virtbase[4];
  71   unsigned char e_filebase[4];
  72 };
  73
  74 struct internal_segdesc
  75 {
  76   unsigned int  a_type:8;       /* Segment type N_TEXT, N_DATA, 0.  */
  77   unsigned int  a_size:24;      /* Segment size.  */
  78   bfd_vma       a_virtbase;     /* Virtual address.  */
  79   unsigned int  a_filebase;     /* Base address in object file.  */
  80 };
  81
  82 #define N_TXTADDR(x) is_this_really_unused?
  83
  84 /* This is documented to be at 1024, but appears to really be at 2048.
  85    FIXME?!  */
  86 #define N_TXTOFF(x)     2048
  87
  88 #define N_TXTSIZE(x) ((x)->a_text)
  89
  90 #define N_DATADDR(x) is_this_really_unused?
  91
  92 #define N_BSSADDR(x) is_this_really_unused?
  93
  94 /* Offsets of the various portions of the file after the text segment.  */
  95
  96 #define N_DATOFF(x)     ( N_TXTOFF(x) + N_TXTSIZE(x) )
  97 #define N_TRELOFF(x)    ( N_DATOFF(x) + (x)->a_data )
  98 #define N_DRELOFF(x)    ( N_TRELOFF(x) + (x)->a_trsize )
  99 #define N_SYMOFF(x)     ( N_DRELOFF(x) + (x)->a_drsize )
 100 #define N_STROFF(x)     ( N_SYMOFF(x) + (x)->a_syms )
 101 \f
 102 /* Symbols.  */
 103 struct external_nlist
 104 {
 105   bfd_byte e_strx[BYTES_IN_WORD];       /* Index into string table of name.  */
 106   bfd_byte e_type[1];                   /* Type of symbol.  */
 107   bfd_byte e_other[1];                  /* Misc info (usually empty).  */
 108   bfd_byte e_desc[2];                   /* Description field.  */
 109   bfd_byte e_value[BYTES_IN_WORD];      /* Value of symbol.  */
 110 };
 111
 112 #define EXTERNAL_NLIST_SIZE (BYTES_IN_WORD+4+BYTES_IN_WORD)
 113
 114 struct internal_nlist
 115 {
 116   unsigned long n_strx;                 /* Index into string table of name.  */
 117   unsigned char n_type;                 /* Type of symbol.  */
 118   unsigned char n_other;                /* Misc info (usually empty).  */
 119   unsigned short n_desc;                /* Description field.  */
 120   bfd_vma n_value;                      /* Value of symbol.  */
 121 };
 122
 123 /* The n_type field is the symbol type, containing:  */
 124
 125 #define N_UNDF  0       /* Undefined symbol.  */
 126 #define N_ABS   2       /* Absolute symbol -- defined at particular addr.  */
 127 #define N_TEXT  4       /* Text sym -- defined at offset in text seg.  */
 128 #define N_DATA  6       /* Data sym -- defined at offset in data seg.  */
 129 #define N_BSS   8       /* BSS  sym -- defined at offset in zero'd seg.  */
 130 #define N_COMM  0x12    /* Common symbol (visible after shared lib dynlink).  */
 131 #define N_FN    0x1f    /* File name of .o file.  */
 132 #define N_FN_SEQ 0x0C   /* N_FN from Sequent compilers (sigh).  */
 133 /* Note: N_EXT can only be usefully OR-ed with N_UNDF, N_ABS, N_TEXT,
 134    N_DATA, or N_BSS.  When the low-order bit of other types is set,
 135    (e.g. N_WARNING versus N_FN), they are two different types.  */
 136 #define N_EXT   1       /* External symbol (as opposed to local-to-this-file).  */
 137 #define N_TYPE  0x1e
 138 #define N_STAB  0xe0    /* If any of these bits are on, it's a debug symbol.  */
 139
 140 #define N_INDR 0x0a
 141
 142 /* The following symbols refer to set elements.
 143    All the N_SET[ATDB] symbols with the same name form one set.
 144    Space is allocated for the set in the text section, and each set
 145    elements value is stored into one word of the space.
 146    The first word of the space is the length of the set (number of elements).
 147
 148    The address of the set is made into an N_SETV symbol
 149    whose name is the same as the name of the set.
 150    This symbol acts like a N_DATA global symbol
 151    in that it can satisfy undefined external references.  */
 152
 153 /* These appear as input to LD, in a .o file.  */
 154 #define N_SETA  0x14            /* Absolute set element symbol.  */
 155 #define N_SETT  0x16            /* Text set element symbol.  */
 156 #define N_SETD  0x18            /* Data set element symbol.  */
 157 #define N_SETB  0x1A            /* Bss set element symbol.  */
 158
 159 /* This is output from LD.  */
 160 #define N_SETV  0x1C            /* Pointer to set vector in data area.  */
 161
 162 /* Warning symbol. The text gives a warning message, the next symbol
 163    in the table will be undefined. When the symbol is referenced, the
 164    message is printed.  */
 165
 166 #define N_WARNING 0x1e
 167
 168 /* Relocations
 169
 170   There are two types of relocation flavours for a.out systems,
 171   standard and extended. The standard form is used on systems where the
 172   instruction has room for all the bits of an offset to the operand, whilst
 173   the extended form is used when an address operand has to be split over n
 174   instructions. Eg, on the 68k, each move instruction can reference
 175   the target with a displacement of 16 or 32 bits. On the sparc, move
 176   instructions use an offset of 14 bits, so the offset is stored in
 177   the reloc field, and the data in the section is ignored.  */
 178
 179 /* This structure describes a single relocation to be performed.
 180    The text-relocation section of the file is a vector of these structures,
 181    all of which apply to the text section.
 182    Likewise, the data-relocation section applies to the data section.  */
 183
 184 struct reloc_std_external
 185 {
 186   bfd_byte r_address[BYTES_IN_WORD];    /* Offset of data to relocate.  */
 187   bfd_byte r_index[3];                  /* Symbol table index of symbol.  */
 188   bfd_byte r_type[1];                   /* Relocation type.  */
 189 };
 190
 191 #define RELOC_STD_BITS_PCREL_BIG        0x80
 192 #define RELOC_STD_BITS_PCREL_LITTLE     0x01
 193
 194 #define RELOC_STD_BITS_LENGTH_BIG       0x60
 195 #define RELOC_STD_BITS_LENGTH_SH_BIG    5       /* To shift to units place.  */
 196 #define RELOC_STD_BITS_LENGTH_LITTLE    0x06
 197 #define RELOC_STD_BITS_LENGTH_SH_LITTLE 1
 198
 199 #define RELOC_STD_BITS_EXTERN_BIG       0x10
 200 #define RELOC_STD_BITS_EXTERN_LITTLE    0x08
 201
 202 #define RELOC_STD_BITS_BASEREL_BIG      0x08
 203 #define RELOC_STD_BITS_BASEREL_LITTLE   0x08
 204
 205 #define RELOC_STD_BITS_JMPTABLE_BIG     0x04
 206 #define RELOC_STD_BITS_JMPTABLE_LITTLE  0x04
 207
 208 #define RELOC_STD_BITS_RELATIVE_BIG     0x02
 209 #define RELOC_STD_BITS_RELATIVE_LITTLE  0x02
 210
 211 #define RELOC_STD_SIZE  (BYTES_IN_WORD + 3 + 1)         /* Bytes per relocation entry.  */
 212
 213 struct reloc_std_internal
 214 {
 215   bfd_vma r_address;            /* Address (within segment) to be relocated.  */
 216   /* The meaning of r_symbolnum depends on r_extern.  */
 217   unsigned int r_symbolnum:24;
 218   /* Nonzero means value is a pc-relative offset
 219      and it should be relocated for changes in its own address
 220      as well as for changes in the symbol or section specified.  */
 221   unsigned int r_pcrel:1;
 222   /* Length (as exponent of 2) of the field to be relocated.
 223      Thus, a value of 2 indicates 1<<2 bytes.  */
 224   unsigned int r_length:2;
 225   /* 1 => relocate with value of symbol.
 226      r_symbolnum is the index of the symbol
 227      in files the symbol table.
 228      0 => relocate with the address of a segment.
 229      r_symbolnum is N_TEXT, N_DATA, N_BSS or N_ABS
 230      (the N_EXT bit may be set also, but signifies nothing).  */
 231   unsigned int r_extern:1;
 232   /* The next three bits are for SunOS shared libraries, and seem to
 233      be undocumented.  */
 234   unsigned int r_baserel:1;     /* Linkage table relative.  */
 235   unsigned int r_jmptable:1;    /* pc-relative to jump table.  */
 236   unsigned int r_relative:1;    /* "relative relocation".  */
 237   /* unused */
 238   unsigned int r_pad:1;         /* Padding -- set to zero.  */
 239 };
 240
 241
 242 /* EXTENDED RELOCS  */
 243
 244 struct reloc_ext_external
 245 {
 246   bfd_byte r_address[BYTES_IN_WORD];    /* Offset of data to relocate.  */
 247   bfd_byte r_index[3];                  /* Symbol table index of symbol.  */
 248   bfd_byte r_type[1];                   /* Relocation type.  */
 249   bfd_byte r_addend[BYTES_IN_WORD];     /* Datum addend.  */
 250 };
 251
 252 #define RELOC_EXT_BITS_EXTERN_BIG       0x80
 253 #define RELOC_EXT_BITS_EXTERN_LITTLE    0x01
 254
 255 #define RELOC_EXT_BITS_TYPE_BIG         0x1F
 256 #define RELOC_EXT_BITS_TYPE_SH_BIG      0
 257 #define RELOC_EXT_BITS_TYPE_LITTLE      0xF8
 258 #define RELOC_EXT_BITS_TYPE_SH_LITTLE   3
 259
 260 /* Bytes per relocation entry */
 261 #define RELOC_EXT_SIZE  (BYTES_IN_WORD + 3 + 1 + BYTES_IN_WORD)
 262
 263 enum reloc_type
 264 {
 265   /* Simple relocations.  */
 266   RELOC_8,                      /* data[0:7] = addend + sv              */
 267   RELOC_16,                     /* data[0:15] = addend + sv             */
 268   RELOC_32,                     /* data[0:31] = addend + sv             */
 269   /* PC-rel displacement.  */
 270   RELOC_DISP8,                  /* data[0:7] = addend - pc + sv         */
 271   RELOC_DISP16,                 /* data[0:15] = addend - pc + sv        */
 272   RELOC_DISP32,                 /* data[0:31] = addend - pc + sv        */
 273   /* Special.  */
 274   RELOC_WDISP30,                /* data[0:29] = (addend + sv - pc)>>2   */
 275   RELOC_WDISP22,                /* data[0:21] = (addend + sv - pc)>>2   */
 276   RELOC_HI22,                   /* data[0:21] = (addend + sv)>>10       */
 277   RELOC_22,                     /* data[0:21] = (addend + sv)           */
 278   RELOC_13,                     /* data[0:12] = (addend + sv)           */
 279   RELOC_LO10,                   /* data[0:9] = (addend + sv)            */
 280   RELOC_SFA_BASE,
 281   RELOC_SFA_OFF13,
 282   /* P.I.C. (base-relative).  */
 283   RELOC_BASE10,                 /* Not sure - maybe we can do this the  */
 284   RELOC_BASE13,                 /* right way now.  */
 285   RELOC_BASE22,
 286   /* For some sort of pc-rel P.I.C. (?)  */
 287   RELOC_PC10,
 288   RELOC_PC22,
 289   /* P.I.C. jump table.  */
 290   RELOC_JMP_TBL,
 291   /* Reputedly for shared libraries somehow.  */
 292   RELOC_SEGOFF16,
 293   RELOC_GLOB_DAT,
 294   RELOC_JMP_SLOT,
 295   RELOC_RELATIVE,
 296
 297   RELOC_11,
 298   RELOC_WDISP2_14,
 299   RELOC_WDISP19,
 300   RELOC_HHI22,                  /* data[0:21] = (addend + sv) >> 42     */
 301   RELOC_HLO10,                  /* data[0:9] = (addend + sv) >> 32      */
 302
 303   /* 29K relocation types */
 304   RELOC_JUMPTARG,
 305   RELOC_CONST,
 306   RELOC_CONSTH,
 307
 308   NO_RELOC
 309 };
 310
 311 struct reloc_internal
 312 {
 313   bfd_vma r_address;            /* Offset of data to relocate.  */
 314   long  r_index;                /* Symbol table index of symbol.  */
 315   enum reloc_type r_type;       /* Relocation type.  */
 316   bfd_vma r_addend;             /* Datum addend.  */
 317 };
 318
 319 #endif  /* __A_OUT_ADOBE_H__ */