coff.h

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/*** coff information for Intel 386/486.  */

/********************** FILE HEADER **********************/

struct external_filehdr {
    unsigned short f_magic;     /* magic number         */
    unsigned short f_nscns;     /* number of sections       */
    unsigned long f_timdat; /* time & date stamp        */
    unsigned long f_symptr; /* file pointer to symtab   */
    unsigned long f_nsyms;      /* number of symtab entries */
    unsigned short f_opthdr;    /* sizeof(optional hdr)     */
    unsigned short f_flags;     /* flags            */
};


/* Bits for f_flags:
 *  F_RELFLG    relocation info stripped from file
 *  F_EXEC      file is executable (no unresolved external references)
 *  F_LNNO      line numbers stripped from file
 *  F_LSYMS     local symbols stripped from file
 *  F_AR32WR    file has byte ordering of an AR32WR machine (e.g. vax)
 */

#define F_RELFLG    (0x0001)
#define F_EXEC      (0x0002)
#define F_LNNO      (0x0004)
#define F_LSYMS     (0x0008)



#define I386MAGIC   0x14c
#define I386AIXMAGIC    0x175
#define I386BADMAG(x) (((x).f_magic!=I386MAGIC) && (x).f_magic!=I386AIXMAGIC)


#define FILHDR  struct external_filehdr
//#define   FILHSZ  sizeof(FILHDR)
#define FILHSZ 20

/********************** AOUT "OPTIONAL HEADER" **********************/


typedef struct 
{
  unsigned short    magic;      /* type of file             */
  unsigned short    vstamp;     /* version stamp            */
  unsigned long tsize;      /* text size in bytes, padded to FW bdry*/
  unsigned long dsize;      /* initialized data "  "        */
  unsigned long bsize;      /* uninitialized data "   "     */
  unsigned long entry;      /* entry pt.                */
  unsigned long     text_start; /* base of text used for this file */
  unsigned long     data_start; /* base of data used for this file */
}
AOUTHDR;


typedef struct gnu_aout {
    unsigned long info;
    unsigned long tsize;
    unsigned long dsize;
    unsigned long bsize;
    unsigned long symsize;
    unsigned long entry;
    unsigned long txrel;
    unsigned long dtrel;
    } GNU_AOUT;

#define AOUTSZ (sizeof(AOUTHDR))

#define OMAGIC          0404    /* object files, eg as output */
#define ZMAGIC          0413    /* demand load format, eg normal ld output */
#define STMAGIC     0401    /* target shlib */
#define SHMAGIC     0443    /* host   shlib */


/********************** SECTION HEADER **********************/


struct external_scnhdr {
    char        s_name[8];  /* section name         */
    unsigned long       s_paddr;    /* physical address, aliased s_nlib */
    unsigned long       s_vaddr;    /* virtual address      */
    unsigned long       s_size;     /* section size         */
    unsigned long       s_scnptr;   /* file ptr to raw data for section */
    unsigned long       s_relptr;   /* file ptr to relocation   */
    unsigned long       s_lnnoptr;  /* file ptr to line numbers */
    unsigned short      s_nreloc;   /* number of relocation entries */
    unsigned short      s_nlnno;    /* number of line number entries*/
    unsigned long       s_flags;    /* flags            */
};

#define SCNHDR  struct external_scnhdr
//#define   SCNHSZ  sizeof(SCNHDR)
#define SCNHSZ 40

/*
 * names of "special" sections
 */
#define _TEXT   ".text"
#define _DATA   ".data"
#define _BSS    ".bss"
#define _COMMENT ".comment"
#define _LIB ".lib"

/*
 * s_flags "type"
 */
#define STYP_TEXT    (0x0020)   /* section contains text only */
#define STYP_DATA    (0x0040)   /* section contains data only */
#define STYP_BSS     (0x0080)   /* section contains bss only */

/********************** LINE NUMBERS **********************/

/* 1 line number entry for every "breakpointable" source line in a section.
 * Line numbers are grouped on a per function basis; first entry in a function
 * grouping will have l_lnno = 0 and in place of physical address will be the
 * symbol table index of the function name.
 */
struct external_lineno {
    union {
        unsigned long l_symndx __attribute__((packed)); /* function name symbol index, iff l_lnno == 0 */
        unsigned long l_paddr __attribute__((packed));      /* (physical) address of line number */
    } l_addr;
    unsigned short l_lnno;                      /* line number */
};


#define LINENO  struct external_lineno
#define LINESZ  sizeof(LINENO)


/********************** SYMBOLS **********************/

#define E_SYMNMLEN  8   /* # characters in a symbol name    */
#define E_FILNMLEN  14  /* # characters in a file name      */
#define E_DIMNUM    4   /* # array dimensions in auxiliary entry */

struct external_syment 
{
  union {
    char e_name[E_SYMNMLEN];
    struct {
      unsigned long e_zeroes __attribute__((packed));
      unsigned long e_offset __attribute__((packed));
    } e;
  } e;
  unsigned long e_value __attribute__((packed));
  short e_scnum;
  unsigned short e_type;
  unsigned char e_sclass;
  unsigned char e_numaux;
};

#define N_BTMASK    (0xf)
#define N_TMASK     (0x30)
#define N_BTSHFT    (4)
#define N_TSHIFT    (2)
  
union external_auxent {
    struct {
        unsigned long x_tagndx __attribute__((packed));     /* str, un, or enum tag indx */
        union {
            struct {
                unsigned short  x_lnno;             /* declaration line number */
                unsigned short  x_size;                 /* str/union/array size */
            } x_lnsz;
            unsigned long x_fsize __attribute__((packed));      /* size of function */
        } x_misc;
        union {
            struct {                    /* if ISFCN, tag, or .bb */
                unsigned long x_lnnoptr __attribute__((packed));    /* ptr to fcn line # */
                unsigned long x_endndx __attribute__((packed)); /* entry ndx past block end */
            } x_fcn;
            struct {                    /* if ISARY, up to 4 dimen. */
                unsigned short x_dimen[E_DIMNUM];
            } x_ary;
        } x_fcnary;
        unsigned short x_tvndx;                     /* tv index */
    } x_sym;

    union {
        char x_fname[E_FILNMLEN];
        struct {
            unsigned long x_zeroes __attribute__((packed));
            unsigned long x_offset __attribute__((packed));
        } x_n;
    } x_file;

    struct {
        unsigned long x_scnlen __attribute__((packed));     /* section length */
        unsigned short x_nreloc;                    /* # relocation entries */
        unsigned short x_nlinno;                    /* # line numbers */
    } x_scn;

        struct {
        unsigned long x_tvfill __attribute__((packed));     /* tv fill value */
        unsigned short x_tvlen;                     /* length of .tv */
        unsigned short x_tvran[2];                  /* tv range */
    } x_tv;     /* info about .tv section (in auxent of symbol .tv)) */


};

#define SYMENT  struct external_syment
//#define   SYMESZ  sizeof(SYMENT)
#define SYMESZ 18
#define AUXENT  union external_auxent
//#define   AUXESZ  sizeof(AUXENT)
#define AUXESZ 18


#   define _ETEXT   "etext"


/* Relocatable symbols have number of the section in which they are defined,
   or one of the following: */

#define N_UNDEF ((short)0)  /* undefined symbol */
#define N_ABS   ((short)-1) /* value of symbol is absolute */
#define N_DEBUG ((short)-2) /* debugging symbol -- value is meaningless */
#define N_TV    ((short)-3) /* indicates symbol needs preload transfer vector */
#define P_TV    ((short)-4) /* indicates symbol needs postload transfer vector*/

/*
 * Type of a symbol, in low N bits of the word
 */
#define T_NULL      0
#define T_VOID      1   /* function argument (only used by compiler) */
#define T_CHAR      2   /* character        */
#define T_SHORT     3   /* short integer    */
#define T_INT       4   /* integer      */
#define T_LONG      5   /* long integer     */
#define T_FLOAT     6   /* floating point   */
#define T_DOUBLE    7   /* double word      */
#define T_STRUCT    8   /* structure        */
#define T_UNION     9   /* union        */
#define T_ENUM      10  /* enumeration      */
#define T_MOE       11  /* member of enumeration*/
#define T_UCHAR     12  /* unsigned character   */
#define T_USHORT    13  /* unsigned short   */
#define T_UINT      14  /* unsigned integer */
#define T_ULONG     15  /* unsigned long    */
#define T_LNGDBL    16  /* long double      */

/*
 * derived types, in n_type
*/
#define DT_NON      (0) /* no derived type */
#define DT_PTR      (1) /* pointer */
#define DT_FCN      (2) /* function */
#define DT_ARY      (3) /* array */

#define BTYPE(x)    ((x) & N_BTMASK)

#define ISPTR(x)    (((x) & N_TMASK) == (DT_PTR << N_BTSHFT))
#define ISFCN(x)    (((x) & N_TMASK) == (DT_FCN << N_BTSHFT))
#define ISARY(x)    (((x) & N_TMASK) == (DT_ARY << N_BTSHFT))
#define ISTAG(x)    ((x)==C_STRTAG||(x)==C_UNTAG||(x)==C_ENTAG)
#define DECREF(x) ((((x)>>N_TSHIFT)&~N_BTMASK)|((x)&N_BTMASK))

/********************** STORAGE CLASSES **********************/

/* This used to be defined as -1, but now n_sclass is unsigned.  */
#define C_EFCN      0xff    /* physical end of function */
#define C_NULL      0
#define C_AUTO      1   /* automatic variable       */
#define C_EXT       2   /* external symbol      */
#define C_STAT      3   /* static           */
#define C_REG       4   /* register variable        */
#define C_EXTDEF    5   /* external definition      */
#define C_LABEL     6   /* label            */
#define C_ULABEL    7   /* undefined label      */
#define C_MOS       8   /* member of structure      */
#define C_ARG       9   /* function argument        */
#define C_STRTAG    10  /* structure tag        */
#define C_MOU       11  /* member of union      */
#define C_UNTAG     12  /* union tag            */
#define C_TPDEF     13  /* type definition      */
#define C_USTATIC   14  /* undefined static     */
#define C_ENTAG     15  /* enumeration tag      */
#define C_MOE       16  /* member of enumeration    */
#define C_REGPARM   17  /* register parameter       */
#define C_FIELD     18  /* bit field            */
#define C_AUTOARG   19  /* auto argument        */
#define C_LASTENT   20  /* dummy entry (end of block)   */
#define C_BLOCK     100 /* ".bb" or ".eb"       */
#define C_FCN       101 /* ".bf" or ".ef"       */
#define C_EOS       102 /* end of structure     */
#define C_FILE      103 /* file name            */
#define C_LINE      104 /* line # reformatted as symbol table entry */
#define C_ALIAS     105 /* duplicate tag        */
#define C_HIDDEN    106 /* ext symbol in dmert public lib */

/********************** RELOCATION DIRECTIVES **********************/



struct external_reloc {
  unsigned long r_vaddr __attribute__((packed));
  unsigned long r_symndx __attribute__((packed));
  unsigned short r_type;
};


#define RELOC struct external_reloc
//#define RELSZ sizeof(RELOC)
#define RELSZ 10

#define DEFAULT_DATA_SECTION_ALIGNMENT 4
#define DEFAULT_BSS_SECTION_ALIGNMENT 4
#define DEFAULT_TEXT_SECTION_ALIGNMENT 4
/* For new sections we havn't heard of before */
#define DEFAULT_SECTION_ALIGNMENT 4