user.h

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/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 1994, 1995, 1996, 1999 by Ralf Baechle
 */
#ifndef _ASM_USER_H
#define _ASM_USER_H

#include <asm/page.h>
#include <asm/reg.h>

/*
 * Core file format: The core file is written in such a way that gdb
 * can understand it and provide useful information to the user (under
 * linux we use the `trad-core' bfd, NOT the irix-core).  The file
 * contents are as follows:
 *
 *  upage: 1 page consisting of a user struct that tells gdb
 *  what is present in the file.  Directly after this is a
 *  copy of the task_struct, which is currently not used by gdb,
 *  but it may come in handy at some point.  All of the registers
 *  are stored as part of the upage.  The upage should always be
 *  only one page long.
 *  data: The data segment follows next.  We use current->end_text to
 *  current->brk to pick up all of the user variables, plus any memory
 *  that may have been sbrk'ed.  No attempt is made to determine if a
 *  page is demand-zero or if a page is totally unused, we just cover
 *  the entire range.  All of the addresses are rounded in such a way
 *  that an integral number of pages is written.
 *  stack: We need the stack information in order to get a meaningful
 *  backtrace.  We need to write the data from usp to
 *  current->start_stack, so we round each of these in order to be able
 *  to write an integer number of pages.
 */
struct user {
    unsigned long   regs[EF_SIZE /      /* integer and fp regs */
            sizeof(unsigned long) + 64];
    size_t      u_tsize;        /* text size (pages) */
    size_t      u_dsize;        /* data size (pages) */
    size_t      u_ssize;        /* stack size (pages) */
    unsigned long   start_code;     /* text starting address */
    unsigned long   start_data;     /* data starting address */
    unsigned long   start_stack;        /* stack starting address */
    long int    signal;         /* signal causing core dump */
    unsigned long   u_ar0;          /* help gdb find registers */
    unsigned long   magic;          /* identifies a core file */
    char        u_comm[32];     /* user command name */
};

#define NBPG            PAGE_SIZE
#define UPAGES          1
#define HOST_TEXT_START_ADDR    (u.start_code)
#define HOST_DATA_START_ADDR    (u.start_data)
#define HOST_STACK_END_ADDR (u.start_stack + u.u_ssize * NBPG)

#endif /* _ASM_USER_H */