gas/a.out.gnu.h

   1 #ifndef __A_OUT_GNU_H__
   2 #define __A_OUT_GNU_H__
   3
   4 #include "aout/reloc.h"
   5
   6 #define __GNU_EXEC_MACROS__
   7
   8 #ifndef __STRUCT_EXEC_OVERRIDE__
   9
  10 /* This is the layout on disk of a Unix V7, Berkeley, SunOS, Vax Ultrix
  11    "struct exec".  Don't assume that on this machine, the "struct exec"
  12    will lay out the same sizes or alignments.  */
  13
  14 struct exec_bytes {
  15         unsigned char a_info[4];
  16         unsigned char a_text[4];
  17         unsigned char a_data[4];
  18         unsigned char a_bss[4];
  19         unsigned char a_syms[4];
  20         unsigned char a_entry[4];
  21         unsigned char a_trsize[4];
  22         unsigned char a_drsize[4];
  23 };
  24
  25 /* How big the "struct exec" is on disk */
  26 #define EXEC_BYTES_SIZE (8 * 4)
  27
  28 /* This is the layout in memory of a "struct exec" while we process it.  */
  29
  30 struct exec
  31 {
  32         unsigned long a_info;           /* Use macros N_MAGIC, etc for access */
  33         unsigned a_text;                /* length of text, in bytes */
  34         unsigned a_data;                /* length of data, in bytes */
  35         unsigned a_bss;         /* length of uninitialized data area for file, in bytes */
  36         unsigned a_syms;                /* length of symbol table data in file, in bytes */
  37         unsigned a_entry;               /* start address */
  38         unsigned a_trsize;              /* length of relocation info for text, in bytes */
  39         unsigned a_drsize;              /* length of relocation info for data, in bytes */
  40 };
  41
  42 #endif /* __STRUCT_EXEC_OVERRIDE__ */
  43
  44 /* these go in the N_MACHTYPE field */
  45 /* These symbols could be defined by code from Suns...punt 'em */
  46 #undef M_UNKNOWN
  47 #undef M_68010
  48 #undef M_68020
  49 #undef M_SPARC
  50 enum machine_type {
  51         M_UNKNOWN = 0,
  52         M_68010 = 1,
  53         M_68020 = 2,
  54         M_SPARC = 3,
  55         /* skip a bunch so we don't run into any of sun's numbers */
  56         M_386 = 100,
  57         M_29K = 101,
  58         M_RS6000 = 102, /* IBM RS/6000 */
  59         /* HP/BSD formats */
  60         M_HP200 = 200,  /* hp200 (68010) BSD binary */
  61         M_HP300 = 300,  /* hp300 (68020+68881) BSD binary */
  62         M_HPUX23 = 0x020C,      /* hp200/300 HPUX binary */
  63 };
  64
  65 #define N_MAGIC(exec) ((exec).a_info & 0xffff)
  66 #define N_MACHTYPE(exec) ((enum machine_type)(((exec).a_info >> 16) & 0xff))
  67 #define N_FLAGS(exec) (((exec).a_info >> 24) & 0xff)
  68 #define N_SET_INFO(exec, magic, type, flags) \
  69     ((exec).a_info = ((magic) & 0xffff) \
  70      | (((int)(type) & 0xff) << 16) \
  71      | (((flags) & 0xff) << 24))
  72 #define N_SET_MAGIC(exec, magic) \
  73     ((exec).a_info = (((exec).a_info & 0xffff0000) | ((magic) & 0xffff)))
  74
  75 #define N_SET_MACHTYPE(exec, machtype) \
  76     ((exec).a_info = \
  77      ((exec).a_info&0xff00ffff) | ((((int)(machtype))&0xff) << 16))
  78
  79 #define N_SET_FLAGS(exec, flags) \
  80     ((exec).a_info = \
  81      ((exec).a_info&0x00ffffff) | (((flags) & 0xff) << 24))
  82
  83 /* Code indicating object file or impure executable.  */
  84 #define OMAGIC 0407
  85 /* Code indicating pure executable.  */
  86 #define NMAGIC 0410
  87 /* Code indicating demand-paged executable.  */
  88 #define ZMAGIC 0413
  89
  90 /* Virtual Address of text segment from the a.out file.  For OMAGIC,
  91    (almost always "unlinked .o's" these days), should be zero.
  92    For linked files, should reflect reality if we know it.  */
  93
  94 #ifndef N_TXTADDR
  95 #define N_TXTADDR(x)    (N_MAGIC(x)==OMAGIC? 0 : TEXT_START_ADDR)
  96 #endif
  97
  98 #ifndef N_BADMAG
  99 #define N_BADMAG(x)       (N_MAGIC(x) != OMAGIC         \
 100                            && N_MAGIC(x) != NMAGIC              \
 101                            && N_MAGIC(x) != ZMAGIC)
 102 #endif
 103
 104 /* By default, segment size is constant.  But on some machines, it can
 105    be a function of the a.out header (e.g. machine type).  */
 106 #ifndef N_SEGSIZE
 107 #define N_SEGSIZE(x)    SEGMENT_SIZE
 108 #endif
 109
 110     /* This complexity is for encapsulated COFF support */
 111 #ifndef _N_HDROFF
 112 #define _N_HDROFF(x)    (N_SEGSIZE(x) - sizeof (struct exec))
 113 #endif
 114
 115 #ifndef N_TXTOFF
 116 #define N_TXTOFF(x)     (N_MAGIC(x) == ZMAGIC ? \
 117                          _N_HDROFF((x)) + sizeof (struct exec) :        \
 118                          sizeof (struct exec))
 119 #endif
 120
 121
 122 #ifndef N_DATOFF
 123 #define N_DATOFF(x)     ( N_TXTOFF(x) + (x).a_text )
 124 #endif
 125
 126 #ifndef N_TRELOFF
 127 #define N_TRELOFF(x)    ( N_DATOFF(x) + (x).a_data )
 128 #endif
 129
 130 #ifndef N_DRELOFF
 131 #define N_DRELOFF(x)    ( N_TRELOFF(x) + (x).a_trsize )
 132 #endif
 133
 134 #ifndef N_SYMOFF
 135 #define N_SYMOFF(x)     ( N_DRELOFF(x) + (x).a_drsize )
 136 #endif
 137
 138 #ifndef N_STROFF
 139 #define N_STROFF(x)     ( N_SYMOFF(x) + (x).a_syms )
 140 #endif
 141
 142 /* Address of text segment in memory after it is loaded.  */
 143 #ifndef N_TXTADDR
 144 #define N_TXTADDR(x)    0
 145 #endif
 146
 147 #ifndef N_DATADDR
 148 #define N_DATADDR(x) \
 149     (N_MAGIC(x)==OMAGIC? (N_TXTADDR(x)+(x).a_text) \
 150      :  (N_SEGSIZE(x) + ((N_TXTADDR(x)+(x).a_text-1) & ~(N_SEGSIZE(x)-1))))
 151 #endif
 152
 153 /* Address of bss segment in memory after it is loaded.  */
 154 #define N_BSSADDR(x) (N_DATADDR(x) + (x).a_data)
 155 \f
 156 struct nlist {
 157         union {
 158                 char *n_name;
 159                 struct nlist *n_next;
 160                 long n_strx;
 161         } n_un;
 162         unsigned char n_type;
 163         char n_other;
 164         short n_desc;
 165         unsigned long n_value;
 166 };
 167
 168 #define N_UNDF 0
 169 #define N_ABS 2
 170 #define N_TEXT 4
 171 #define N_DATA 6
 172 #define N_BSS 8
 173 #define N_COMM  0x12            /* common (visible in shared lib commons) */
 174 #define N_FN 0x1F               /* File name of a .o file */
 175
 176 /* Note: N_EXT can only usefully be OR-ed with N_UNDF, N_ABS, N_TEXT,
 177    N_DATA, or N_BSS.  When the low-order bit of other types is set,
 178    (e.g. N_WARNING versus N_FN), they are two different types.  */
 179 #define N_EXT 1
 180 #define N_TYPE 036
 181 #define N_STAB 0340
 182
 183 /* The following type indicates the definition of a symbol as being
 184    an indirect reference to another symbol.  The other symbol
 185    appears as an undefined reference, immediately following this symbol.
 186
 187    Indirection is asymmetrical.  The other symbol's value will be used
 188    to satisfy requests for the indirect symbol, but not vice versa.
 189    If the other symbol does not have a definition, libraries will
 190    be searched to find a definition.  */
 191
 192 #define N_INDR 0xa
 193
 194 /* The following symbols refer to set elements.
 195    All the N_SET[ATDB] symbols with the same name form one set.
 196    Space is allocated for the set in the text section, and each set
 197    element's value is stored into one word of the space.
 198    The first word of the space is the length of the set (number of elements).
 199
 200    The address of the set is made into an N_SETV symbol
 201    whose name is the same as the name of the set.
 202    This symbol acts like a N_DATA global symbol
 203    in that it can satisfy undefined external references.  */
 204
 205 /* These appear as input to LD, in a .o file.  */
 206 #define N_SETA  0x14            /* Absolute set element symbol */
 207 #define N_SETT  0x16            /* Text set element symbol */
 208 #define N_SETD  0x18            /* Data set element symbol */
 209 #define N_SETB  0x1A            /* Bss set element symbol */
 210
 211 /* This is output from LD.  */
 212 #define N_SETV  0x1C            /* Pointer to set vector in data area.  */
 213
 214 /* Warning symbol. The text gives a warning message, the next symbol
 215    in the table will be undefined. When the symbol is referenced, the
 216    message is printed.  */
 217
 218 #define N_WARNING 0x1e
 219 \f
 220 /* This structure describes a single relocation to be performed.
 221    The text-relocation section of the file is a vector of these structures,
 222    all of which apply to the text section.
 223    Likewise, the data-relocation section applies to the data section.  */
 224
 225 /* The following enum and struct were borrowed from SunOS's
 226    /usr/include/sun4/a.out.h  and extended to handle
 227    other machines.  It is currently used on SPARC and AMD 29000.
 228
 229    reloc_ext_bytes is how it looks on disk.  reloc_info_extended is
 230    how we might process it on a native host.  */
 231
 232 struct reloc_ext_bytes {
 233         unsigned char   r_address[4];
 234         unsigned char r_index[3];
 235         unsigned char r_bits[1];
 236         unsigned char r_addend[4];
 237 };
 238
 239 #define RELOC_EXT_BITS_EXTERN_BIG       0x80
 240 #define RELOC_EXT_BITS_EXTERN_LITTLE    0x01
 241
 242 #define RELOC_EXT_BITS_TYPE_BIG         0x1F
 243 #define RELOC_EXT_BITS_TYPE_SH_BIG      0
 244 #define RELOC_EXT_BITS_TYPE_LITTLE      0xF8
 245 #define RELOC_EXT_BITS_TYPE_SH_LITTLE   3
 246
 247 #define RELOC_EXT_SIZE  12              /* Bytes per relocation entry */
 248
 249 struct reloc_info_extended
 250 {
 251         unsigned long r_address;
 252         unsigned int  r_index:24;
 253 # define        r_symbolnum  r_index
 254         unsigned        r_extern:1;
 255         unsigned        :2;
 256         /*  RS/6000 compiler does not support enum bitfield
 257             enum reloc_type r_type:5; */
 258         enum reloc_type r_type;
 259         long int        r_addend;
 260 };
 261
 262 /* The standard, old-fashioned, Berkeley compatible relocation struct */
 263
 264 struct reloc_std_bytes {
 265         unsigned char   r_address[4];
 266         unsigned char r_index[3];
 267         unsigned char r_bits[1];
 268 };
 269
 270 #define RELOC_STD_BITS_PCREL_BIG        0x80
 271 #define RELOC_STD_BITS_PCREL_LITTLE     0x01
 272
 273 #define RELOC_STD_BITS_LENGTH_BIG       0x60
 274 #define RELOC_STD_BITS_LENGTH_SH_BIG    5       /* To shift to units place */
 275 #define RELOC_STD_BITS_LENGTH_LITTLE    0x06
 276 #define RELOC_STD_BITS_LENGTH_SH_LITTLE 1
 277
 278 #define RELOC_STD_BITS_EXTERN_BIG       0x10
 279 #define RELOC_STD_BITS_EXTERN_LITTLE    0x08
 280
 281 #define RELOC_STD_BITS_BASEREL_BIG      0x08
 282 #define RELOC_STD_BITS_BASEREL_LITTLE   0x08
 283
 284 #define RELOC_STD_BITS_JMPTABLE_BIG     0x04
 285 #define RELOC_STD_BITS_JMPTABLE_LITTLE  0x04
 286
 287 #define RELOC_STD_BITS_RELATIVE_BIG     0x02
 288 #define RELOC_STD_BITS_RELATIVE_LITTLE  0x02
 289
 290 #define RELOC_STD_SIZE  8               /* Bytes per relocation entry */
 291
 292 #ifndef CUSTOM_RELOC_FORMAT
 293 struct relocation_info
 294 {
 295         /* Address (within segment) to be relocated.  */
 296         int r_address;
 297         /* The meaning of r_symbolnum depends on r_extern.  */
 298         unsigned int r_symbolnum:24;
 299         /* Nonzero means value is a pc-relative offset
 300            and it should be relocated for changes in its own address
 301            as well as for changes in the symbol or section specified.  */
 302         unsigned int r_pcrel:1;
 303         /* Length (as exponent of 2) of the field to be relocated.
 304            Thus, a value of 2 indicates 1<<2 bytes.  */
 305         unsigned int r_length:2;
 306         /* 1 => relocate with value of symbol.
 307            r_symbolnum is the index of the symbol
 308            in file's the symbol table.
 309            0 => relocate with the address of a segment.
 310            r_symbolnum is N_TEXT, N_DATA, N_BSS or N_ABS
 311            (the N_EXT bit may be set also, but signifies nothing).  */
 312         unsigned int r_extern:1;
 313         /* The next three bits are for SunOS shared libraries, and seem to
 314            be undocumented.  */
 315         unsigned int r_baserel:1;       /* Linkage table relative */
 316         unsigned int r_jmptable:1;      /* pc-relative to jump table */
 317
 318 #ifdef TC_NS32K
 319 #define r_bsr   r_baserel
 320 #define r_disp  r_jmptable
 321 #endif /* TC_NS32K */
 322
 323         unsigned int r_relative:1;      /* "relative relocation" */
 324         /* unused */
 325         unsigned int r_pad:1;           /* Padding -- set to zero */
 326 };
 327 #endif /* CUSTOM_RELOC_FORMAT */
 328
 329 #endif /* __A_OUT_GNU_H__ */
 330
 331 /* end of a.out.gnu.h */