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/*
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 *  m68k/ColdFire Semihosting syscall interface
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 *
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 *  Copyright (c) 2005-2007 CodeSourcery.
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 *
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 *  This program is free software; you can redistribute it and/or modify
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 *  it under the terms of the GNU General Public License as published by
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 *  the Free Software Foundation; either version 2 of the License, or
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 *  (at your option) any later version.
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 *
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 *  This program is distributed in the hope that it will be useful,
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 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
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 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 *  GNU General Public License for more details.
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 *
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 *  You should have received a copy of the GNU General Public License
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 *  along with this program; if not, write to the Free Software
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 *  Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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 *  MA 02110-1301, USA.
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 */
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <stdlib.h>
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#include <stdio.h>
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#include <sys/time.h>
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#include <time.h>
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#include "cpu.h"
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#if defined(CONFIG_USER_ONLY)
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#include "qemu.h"
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#define SEMIHOSTING_HEAP_SIZE (128 * 1024 * 1024)
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#else
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#include "qemu-common.h"
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#include "sysemu.h"
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#include "gdbstub.h"
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#include "softmmu-semi.h"
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#endif
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#define HOSTED_EXIT  0
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#define HOSTED_INIT_SIM 1
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#define HOSTED_OPEN 2
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#define HOSTED_CLOSE 3
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#define HOSTED_READ 4
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#define HOSTED_WRITE 5
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#define HOSTED_LSEEK 6
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#define HOSTED_RENAME 7
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#define HOSTED_UNLINK 8
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#define HOSTED_STAT 9
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#define HOSTED_FSTAT 10
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#define HOSTED_GETTIMEOFDAY 11
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#define HOSTED_ISATTY 12
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#define HOSTED_SYSTEM 13
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typedef uint32_t gdb_mode_t;
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typedef uint32_t gdb_time_t;
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struct m68k_gdb_stat {
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  uint32_t    gdb_st_dev;     /* device */
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  uint32_t    gdb_st_ino;     /* inode */
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  gdb_mode_t  gdb_st_mode;    /* protection */
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  uint32_t    gdb_st_nlink;   /* number of hard links */
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  uint32_t    gdb_st_uid;     /* user ID of owner */
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  uint32_t    gdb_st_gid;     /* group ID of owner */
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  uint32_t    gdb_st_rdev;    /* device type (if inode device) */
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  uint64_t    gdb_st_size;    /* total size, in bytes */
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  uint64_t    gdb_st_blksize; /* blocksize for filesystem I/O */
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  uint64_t    gdb_st_blocks;  /* number of blocks allocated */
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  gdb_time_t  gdb_st_atime;   /* time of last access */
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  gdb_time_t  gdb_st_mtime;   /* time of last modification */
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  gdb_time_t  gdb_st_ctime;   /* time of last change */
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} __attribute__((packed));
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struct gdb_timeval {
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  gdb_time_t tv_sec;  /* second */
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  uint64_t tv_usec;   /* microsecond */
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} __attribute__((packed));
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#define GDB_O_RDONLY   0x0
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#define GDB_O_WRONLY   0x1
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#define GDB_O_RDWR     0x2
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#define GDB_O_APPEND   0x8
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#define GDB_O_CREAT  0x200
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#define GDB_O_TRUNC  0x400
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#define GDB_O_EXCL   0x800
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static int translate_openflags(int flags)
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{
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    int hf;
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    if (flags & GDB_O_WRONLY)
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        hf = O_WRONLY;
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    else if (flags & GDB_O_RDWR)
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        hf = O_RDWR;
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    else
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        hf = O_RDONLY;
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    if (flags & GDB_O_APPEND) hf |= O_APPEND;
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    if (flags & GDB_O_CREAT) hf |= O_CREAT;
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    if (flags & GDB_O_TRUNC) hf |= O_TRUNC;
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    if (flags & GDB_O_EXCL) hf |= O_EXCL;
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    return hf;
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}
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static void translate_stat(CPUState *env, target_ulong addr, struct stat *s)
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{
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    struct m68k_gdb_stat *p;
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    if (!(p = lock_user(VERIFY_WRITE, addr, sizeof(struct m68k_gdb_stat), 0)))
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        /* FIXME - should this return an error code? */
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        return;
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    p->gdb_st_dev = cpu_to_be32(s->st_dev);
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    p->gdb_st_ino = cpu_to_be32(s->st_ino);
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    p->gdb_st_mode = cpu_to_be32(s->st_mode);
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    p->gdb_st_nlink = cpu_to_be32(s->st_nlink);
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    p->gdb_st_uid = cpu_to_be32(s->st_uid);
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    p->gdb_st_gid = cpu_to_be32(s->st_gid);
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    p->gdb_st_rdev = cpu_to_be32(s->st_rdev);
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    p->gdb_st_size = cpu_to_be64(s->st_size);
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#ifdef _WIN32
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    /* Windows stat is missing some fields.  */
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    p->gdb_st_blksize = 0;
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    p->gdb_st_blocks = 0;
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#else
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    p->gdb_st_blksize = cpu_to_be64(s->st_blksize);
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    p->gdb_st_blocks = cpu_to_be64(s->st_blocks);
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#endif
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    p->gdb_st_atime = cpu_to_be32(s->st_atime);
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    p->gdb_st_mtime = cpu_to_be32(s->st_mtime);
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    p->gdb_st_ctime = cpu_to_be32(s->st_ctime);
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    unlock_user(p, addr, sizeof(struct m68k_gdb_stat));
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}
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static int m68k_semi_is_fseek;
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static void m68k_semi_cb(CPUState *env, target_ulong ret, target_ulong err)
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{
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    target_ulong args;
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    args = env->dregs[1];
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    if (m68k_semi_is_fseek) {
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        /* FIXME: We've already lost the high bits of the fseek
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           return value.  */
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        /* FIXME - handle put_user() failure */
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        put_user_u32(0, args);
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        args += 4;
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        m68k_semi_is_fseek = 0;
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    }
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    /* FIXME - handle put_user() failure */
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    put_user_u32(ret, args);
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    put_user_u32(errno, args + 4);
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}
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#define ARG(n)                                        \
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({                                                \
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    target_ulong __arg;                                \
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    /* FIXME - handle get_user() failure */        \
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    get_user_ual(__arg, args + (n) * 4);        \
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    __arg;                                        \
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})
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#define PARG(x) ((unsigned long)ARG(x))
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void do_m68k_semihosting(CPUM68KState *env, int nr)
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{
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    uint32_t args;
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    void *p;
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    void *q;
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    uint32_t len;
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    uint32_t result;
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    args = env->dregs[1];
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    switch (nr) {
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    case HOSTED_EXIT:
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        exit(env->dregs[0]);
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    case HOSTED_OPEN:
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        if (use_gdb_syscalls()) {
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            gdb_do_syscall(m68k_semi_cb, "open,%s,%x,%x", ARG(0), (int)ARG(1),
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                           ARG(2), ARG(3));
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            return;
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        } else {
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            if (!(p = lock_user_string(ARG(0)))) {
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                /* FIXME - check error code? */
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                result = -1;
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            } else {
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                result = open(p, translate_openflags(ARG(2)), ARG(3));
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                unlock_user(p, ARG(0), 0);
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            }
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        }
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        break;
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    case HOSTED_CLOSE:
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        {
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            /* Ignore attempts to close stdin/out/err.  */
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            int fd = ARG(0);
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            if (fd > 2) {
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                if (use_gdb_syscalls()) {
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                    gdb_do_syscall(m68k_semi_cb, "close,%x", ARG(0));
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                    return;
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                } else {
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                    result = close(fd);
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                }
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            } else {
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                result = 0;
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            }
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            break;
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        }
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    case HOSTED_READ:
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        len = ARG(2);
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        if (use_gdb_syscalls()) {
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            gdb_do_syscall(m68k_semi_cb, "read,%x,%x,%x",
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                           ARG(0), ARG(1), len);
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            return;
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        } else {
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            if (!(p = lock_user(VERIFY_WRITE, ARG(1), len, 0))) {
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                /* FIXME - check error code? */
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                result = -1;
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            } else {
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                result = read(ARG(0), p, len);
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                unlock_user(p, ARG(1), len);
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            }
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        }
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        break;
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    case HOSTED_WRITE:
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        len = ARG(2);
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        if (use_gdb_syscalls()) {
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            gdb_do_syscall(m68k_semi_cb, "write,%x,%x,%x",
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                           ARG(0), ARG(1), len);
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            return;
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        } else {
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            if (!(p = lock_user(VERIFY_READ, ARG(1), len, 1))) {
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                /* FIXME - check error code? */
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                result = -1;
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            } else {
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                result = write(ARG(0), p, len);
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                unlock_user(p, ARG(0), 0);
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            }
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        }
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        break;
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    case HOSTED_LSEEK:
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        {
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            uint64_t off;
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            off = (uint32_t)ARG(2) | ((uint64_t)ARG(1) << 32);
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            if (use_gdb_syscalls()) {
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                m68k_semi_is_fseek = 1;
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                gdb_do_syscall(m68k_semi_cb, "fseek,%x,%lx,%x",
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                               ARG(0), off, ARG(3));
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            } else {
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                off = lseek(ARG(0), off, ARG(3));
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                /* FIXME - handle put_user() failure */
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                put_user_u32(off >> 32, args);
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                put_user_u32(off, args + 4);
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                put_user_u32(errno, args + 8);
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            }
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            return;
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        }
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    case HOSTED_RENAME:
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        if (use_gdb_syscalls()) {
260 5fafdf24 ths
            gdb_do_syscall(m68k_semi_cb, "rename,%s,%s",
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                           ARG(0), (int)ARG(1), ARG(2), (int)ARG(3));
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            return;
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        } else {
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            p = lock_user_string(ARG(0));
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            q = lock_user_string(ARG(2));
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            if (!p || !q) {
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                /* FIXME - check error code? */
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                result = -1;
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            } else {
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                result = rename(p, q);
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            }
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            unlock_user(p, ARG(0), 0);
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            unlock_user(q, ARG(2), 0);
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        }
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        break;
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    case HOSTED_UNLINK:
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        if (use_gdb_syscalls()) {
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            gdb_do_syscall(m68k_semi_cb, "unlink,%s",
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                           ARG(0), (int)ARG(1));
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            return;
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        } else {
282 579a97f7 bellard
            if (!(p = lock_user_string(ARG(0)))) {
283 579a97f7 bellard
                /* FIXME - check error code? */
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                result = -1;
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            } else {
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                result = unlink(p);
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                unlock_user(p, ARG(0), 0);
288 579a97f7 bellard
            }
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        }
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        break;
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    case HOSTED_STAT:
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        if (use_gdb_syscalls()) {
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            gdb_do_syscall(m68k_semi_cb, "stat,%s,%x",
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                           ARG(0), (int)ARG(1), ARG(2));
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            return;
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        } else {
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            struct stat s;
298 579a97f7 bellard
            if (!(p = lock_user_string(ARG(0)))) {
299 579a97f7 bellard
                /* FIXME - check error code? */
300 579a97f7 bellard
                result = -1;
301 579a97f7 bellard
            } else {
302 579a97f7 bellard
                result = stat(p, &s);
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                unlock_user(p, ARG(0), 0);
304 579a97f7 bellard
            }
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            if (result == 0) {
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                translate_stat(env, ARG(2), &s);
307 a87295e8 pbrook
            }
308 a87295e8 pbrook
        }
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        break;
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    case HOSTED_FSTAT:
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        if (use_gdb_syscalls()) {
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            gdb_do_syscall(m68k_semi_cb, "fstat,%x,%x",
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                           ARG(0), ARG(1));
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            return;
315 a87295e8 pbrook
        } else {
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            struct stat s;
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            result = fstat(ARG(0), &s);
318 a87295e8 pbrook
            if (result == 0) {
319 a87295e8 pbrook
                translate_stat(env, ARG(1), &s);
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            }
321 a87295e8 pbrook
        }
322 a87295e8 pbrook
        break;
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    case HOSTED_GETTIMEOFDAY:
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        if (use_gdb_syscalls()) {
325 a87295e8 pbrook
            gdb_do_syscall(m68k_semi_cb, "gettimeofday,%x,%x",
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                           ARG(0), ARG(1));
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            return;
328 a87295e8 pbrook
        } else {
329 29b3a662 pbrook
            qemu_timeval tv;
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            struct gdb_timeval *p;
331 29b3a662 pbrook
            result = qemu_gettimeofday(&tv);
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            if (result != 0) {
333 579a97f7 bellard
                if (!(p = lock_user(VERIFY_WRITE,
334 579a97f7 bellard
                                    ARG(0), sizeof(struct gdb_timeval), 0))) {
335 579a97f7 bellard
                    /* FIXME - check error code? */
336 579a97f7 bellard
                    result = -1;
337 579a97f7 bellard
                } else {
338 579a97f7 bellard
                    p->tv_sec = cpu_to_be32(tv.tv_sec);
339 579a97f7 bellard
                    p->tv_usec = cpu_to_be64(tv.tv_usec);
340 579a97f7 bellard
                    unlock_user(p, ARG(0), sizeof(struct gdb_timeval));
341 579a97f7 bellard
                }
342 a87295e8 pbrook
            }
343 a87295e8 pbrook
        }
344 a87295e8 pbrook
        break;
345 a87295e8 pbrook
    case HOSTED_ISATTY:
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        if (use_gdb_syscalls()) {
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            gdb_do_syscall(m68k_semi_cb, "isatty,%x", ARG(0));
348 a87295e8 pbrook
            return;
349 a87295e8 pbrook
        } else {
350 a87295e8 pbrook
            result = isatty(ARG(0));
351 a87295e8 pbrook
        }
352 a87295e8 pbrook
        break;
353 a87295e8 pbrook
    case HOSTED_SYSTEM:
354 a87295e8 pbrook
        if (use_gdb_syscalls()) {
355 a87295e8 pbrook
            gdb_do_syscall(m68k_semi_cb, "system,%s",
356 a87295e8 pbrook
                           ARG(0), (int)ARG(1));
357 a87295e8 pbrook
            return;
358 a87295e8 pbrook
        } else {
359 579a97f7 bellard
            if (!(p = lock_user_string(ARG(0)))) {
360 579a97f7 bellard
                /* FIXME - check error code? */
361 579a97f7 bellard
                result = -1;
362 579a97f7 bellard
            } else {
363 579a97f7 bellard
                result = system(p);
364 579a97f7 bellard
                unlock_user(p, ARG(0), 0);
365 579a97f7 bellard
            }
366 a87295e8 pbrook
        }
367 a87295e8 pbrook
        break;
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    case HOSTED_INIT_SIM:
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#if defined(CONFIG_USER_ONLY)
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        {
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        TaskState *ts = env->opaque;
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        /* Allocate the heap using sbrk.  */
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        if (!ts->heap_limit) {
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            long ret;
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            uint32_t size;
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            uint32_t base;
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            base = do_brk(0);
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            size = SEMIHOSTING_HEAP_SIZE;
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            /* Try a big heap, and reduce the size if that fails.  */
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            for (;;) {
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                ret = do_brk(base + size);
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                if (ret != -1)
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                    break;
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                size >>= 1;
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            }
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            ts->heap_limit = base + size;
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        }
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        /* This call may happen before we have writable memory, so return
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           values directly in registers.  */
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        env->dregs[1] = ts->heap_limit;
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        env->aregs[7] = ts->stack_base;
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        }
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#else
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        /* FIXME: This is wrong for boards where RAM does not start at
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           address zero.  */
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        env->dregs[1] = ram_size;
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        env->aregs[7] = ram_size;
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#endif
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        return;
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    default:
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        cpu_abort(env, "Unsupported semihosting syscall %d\n", nr);
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        result = 0;
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    }
405 2f619698 bellard
    /* FIXME - handle put_user() failure */
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    put_user_u32(result, args);
407 2f619698 bellard
    put_user_u32(errno, args + 4);
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}