usr/src/cmd/lisp/h/naout.h

/* sccs id  @(#)naout.h 34.1  10/3/80  */

/* u_* types come from <sys/types.h> */
/* PAGSIZ comes from <pagsiz.h> */
/*
 * Header prepended to each a.out file.
 */
struct exec {
        long    a_magic;        /* magic number */
        u_long  a_text;         /* size of text segment */
        u_long  a_data;         /* size of initialized data */
        u_long  a_bss;          /* size of uninitialized data */
        u_long  a_syms;         /* size of symbol table */
        u_long  a_entry;        /* entry point */
        u_long  a_trsize;       /* size of text relocation */
        u_long  a_drsize;       /* size of data relocation */
};

#define OMAGIC  0407            /* old impure format */
#define NMAGIC  0410            /* read-only text */
#define ZMAGIC  0413            /* demand load format */

/*
 * Macros which take exec structures as arguments and tell whether
 * the file has a reasonable magic number or offsets to text|symbols|strings.
 */
#define N_BADMAG(x) \
    (((x).a_magic)!=OMAGIC && ((x).a_magic)!=NMAGIC && ((x).a_magic)!=ZMAGIC)

#define N_TXTOFF(x) \
        ((x).a_magic==ZMAGIC ? PAGSIZ : sizeof (struct exec))
#define N_SYMOFF(x) \
        (N_TXTOFF(x) + (x).a_text+(x).a_data + (x).a_trsize+(x).a_drsize)
#define N_STROFF(x) \
        (N_SYMOFF(x) + (x).a_syms)

/*
 * Format of a relocation datum.
 */
struct relocation_info {
        int     r_address;      /* address which is relocated */
        u_int   r_symbolnum:24, /* local symbol ordinal */
                r_pcrel:1,      /* was relocated pc relative already */
                r_length:2,     /* 0=byte, 1=word, 2=long */
                r_extern:1,     /* does not include value of sym referenced */
                :4;             /* nothing, yet */
};

/*
 * Format of a symbol table entry; this file is included by <a.out.h>
 * and should be used if you aren't interested the a.out header
 * or relocation information.
 */
struct  nlist {
        union {
                char    *n_name;        /* for use when in-core */
                long    n_strx;         /* index into file string table */
        } n_un;
        u_char  n_type;         /* type flag, i.e. N_TEXT etc; see below */
        char    n_other;        /* unused */
        short   n_desc;         /* see <stab.h> */
        u_long  n_value;        /* value of this symbol (or sdb offset) */
};
#define n_hash  n_desc          /* used internally by ld */

/*
 * Simple values for n_type.
 */
#define N_UNDF  0x0             /* undefined */
#define N_ABS   0x2             /* absolute */
#define N_TEXT  0x4             /* text */
#define N_DATA  0x6             /* data */
#define N_BSS   0x8             /* bss */
#define N_COMM  0x12            /* common (internal to ld) */
#define N_FN    0x1f            /* file name symbol */

#define N_EXT   01              /* external bit, or'ed in */
#define N_TYPE  0x1e            /* mask for all the type bits */

/*
 * Sdb entries have some of the N_STAB bits set.
 * These are given in <stab.h>
 */
#define N_STAB  0xe0            /* if any of these bits set, a SDB entry */

/*
 * Format for namelist values.
 */
#define N_FORMAT        "%08x"