syscall_emul.cc revision 1969
1/* 2 * Copyright (c) 2003-2005 The Regents of The University of Michigan 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are 7 * met: redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer; 9 * redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution; 12 * neither the name of the copyright holders nor the names of its 13 * contributors may be used to endorse or promote products derived from 14 * this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29#include <unistd.h> 30 31#include <string> 32#include <iostream> 33 34#include "sim/syscall_emul.hh" 35#include "base/trace.hh" 36#include "cpu/exec_context.hh" 37#include "cpu/base.hh" 38#include "sim/process.hh" 39 40#include "sim/sim_events.hh" 41 42using namespace std; 43 44void 45SyscallDesc::doSyscall(int callnum, Process *process, ExecContext *xc) 46{ 47 DPRINTFR(SyscallVerbose, "%s: syscall %s called\n", 48 xc->cpu->name(), name); 49 50 SyscallReturn retval = (*funcPtr)(this, callnum, process, xc); 51 52 DPRINTFR(SyscallVerbose, "%s: syscall %s returns %d\n", 53 xc->cpu->name(), name, retval.value()); 54 55 if (!(flags & SyscallDesc::SuppressReturnValue)) 56 xc->setSyscallReturn(retval); 57} 58 59 60SyscallReturn 61unimplementedFunc(SyscallDesc *desc, int callnum, Process *process, 62 ExecContext *xc) 63{ 64 fatal("syscall %s (#%d) unimplemented.", desc->name, callnum); 65} 66 67 68SyscallReturn 69ignoreFunc(SyscallDesc *desc, int callnum, Process *process, 70 ExecContext *xc) 71{ 72 warn("ignoring syscall %s(%d, %d, ...)", desc->name, 73 xc->getSyscallArg(0), xc->getSyscallArg(1)); 74 75 return 0; 76} 77 78 79SyscallReturn 80exitFunc(SyscallDesc *desc, int callnum, Process *process, 81 ExecContext *xc) 82{ 83 new SimExitEvent("syscall caused exit", xc->getSyscallArg(0) & 0xff); 84 85 return 1; 86} 87 88 89SyscallReturn 90getpagesizeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 91{ 92 return VMPageSize; 93} 94 95 96SyscallReturn 97obreakFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 98{ 99 // change brk addr to first arg 100 Addr new_brk = xc->getSyscallArg(0); 101 if (new_brk != 0) 102 { 103 p->brk_point = xc->getSyscallArg(0); 104 } 105 DPRINTF(SyscallVerbose, "Break Point changed to: %#X\n", p->brk_point); 106 return p->brk_point; 107} 108 109 110SyscallReturn 111closeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 112{ 113 int fd = p->sim_fd(xc->getSyscallArg(0)); 114 return close(fd); 115} 116 117 118SyscallReturn 119readFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 120{ 121 int fd = p->sim_fd(xc->getSyscallArg(0)); 122 int nbytes = xc->getSyscallArg(2); 123 BufferArg bufArg(xc->getSyscallArg(1), nbytes); 124 125 int bytes_read = read(fd, bufArg.bufferPtr(), nbytes); 126 127 if (bytes_read != -1) 128 bufArg.copyOut(xc->mem); 129 130 return bytes_read; 131} 132 133SyscallReturn 134writeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 135{ 136 int fd = p->sim_fd(xc->getSyscallArg(0)); 137 int nbytes = xc->getSyscallArg(2); 138 BufferArg bufArg(xc->getSyscallArg(1), nbytes); 139 140 bufArg.copyIn(xc->mem); 141 142 int bytes_written = write(fd, bufArg.bufferPtr(), nbytes); 143 144 fsync(fd); 145 146 return bytes_written; 147} 148 149 150SyscallReturn 151lseekFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 152{ 153 int fd = p->sim_fd(xc->getSyscallArg(0)); 154 uint64_t offs = xc->getSyscallArg(1); 155 int whence = xc->getSyscallArg(2); 156 157 off_t result = lseek(fd, offs, whence); 158 159 return (result == (off_t)-1) ? -errno : result; 160} 161 162 163SyscallReturn 164munmapFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 165{ 166 // given that we don't really implement mmap, munmap is really easy 167 return 0; 168} 169 170 171const char *hostname = "m5.eecs.umich.edu"; 172 173SyscallReturn 174gethostnameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 175{ 176 int name_len = xc->getSyscallArg(1); 177 BufferArg name(xc->getSyscallArg(0), name_len); 178 179 strncpy((char *)name.bufferPtr(), hostname, name_len); 180 181 name.copyOut(xc->mem); 182 183 return 0; 184} 185 186SyscallReturn 187unlinkFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 188{ 189 string path; 190 191 if (xc->mem->readString(path, xc->getSyscallArg(0)) != No_Fault) 192 return (TheISA::IntReg)-EFAULT; 193 194 int result = unlink(path.c_str()); 195 return (result == -1) ? -errno : result; 196} 197 198SyscallReturn 199renameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 200{ 201 string old_name; 202 203 if (xc->mem->readString(old_name, xc->getSyscallArg(0)) != No_Fault) 204 return -EFAULT; 205 206 string new_name; 207 208 if (xc->mem->readString(new_name, xc->getSyscallArg(1)) != No_Fault) 209 return -EFAULT; 210 211 int64_t result = rename(old_name.c_str(), new_name.c_str()); 212 return (result == -1) ? -errno : result; 213} 214 215SyscallReturn 216truncateFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc) 217{ 218 string path; 219 220 if (xc->mem->readString(path, xc->getSyscallArg(0)) != No_Fault) 221 return -EFAULT; 222 223 off_t length = xc->getSyscallArg(1); 224 225 int result = truncate(path.c_str(), length); 226 return (result == -1) ? -errno : result; 227} 228 229SyscallReturn 230ftruncateFunc(SyscallDesc *desc, int num, Process *process, ExecContext *xc) 231{ 232 int fd = process->sim_fd(xc->getSyscallArg(0)); 233 234 if (fd < 0) 235 return -EBADF; 236 237 off_t length = xc->getSyscallArg(1); 238 239 int result = ftruncate(fd, length); 240 return (result == -1) ? -errno : result; 241} 242