sim/syscall_emul.cc

   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
  42 using namespace std;
  43
  44 void
  45 SyscallDesc::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
  60 SyscallReturn
  61 unimplementedFunc(SyscallDesc *desc, int callnum, Process *process,
  62                   ExecContext *xc)
  63 {
  64     fatal("syscall %s (#%d) unimplemented.", desc->name, callnum);
  65 }
  66
  67
  68 SyscallReturn
  69 ignoreFunc(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
  79 SyscallReturn
  80 exitFunc(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
  89 SyscallReturn
  90 getpagesizeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
  91 {
  92     return VMPageSize;
  93 }
  94
  95
  96 SyscallReturn
  97 obreakFunc(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
 110 SyscallReturn
 111 closeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 112 {
 113     int target_fd = xc->getSyscallArg(0);
 114     int status = close(p->sim_fd(target_fd));
 115     if (status >= 0)
 116         p->free_fd(target_fd);
 117     return status;
 118 }
 119
 120
 121 SyscallReturn
 122 readFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 123 {
 124     int fd = p->sim_fd(xc->getSyscallArg(0));
 125     int nbytes = xc->getSyscallArg(2);
 126     BufferArg bufArg(xc->getSyscallArg(1), nbytes);
 127
 128     int bytes_read = read(fd, bufArg.bufferPtr(), nbytes);
 129
 130     if (bytes_read != -1)
 131         bufArg.copyOut(xc->mem);
 132
 133     return bytes_read;
 134 }
 135
 136 SyscallReturn
 137 writeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 138 {
 139     int fd = p->sim_fd(xc->getSyscallArg(0));
 140     int nbytes = xc->getSyscallArg(2);
 141     BufferArg bufArg(xc->getSyscallArg(1), nbytes);
 142
 143     bufArg.copyIn(xc->mem);
 144
 145     int bytes_written = write(fd, bufArg.bufferPtr(), nbytes);
 146
 147     fsync(fd);
 148
 149     return bytes_written;
 150 }
 151
 152
 153 SyscallReturn
 154 lseekFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 155 {
 156     int fd = p->sim_fd(xc->getSyscallArg(0));
 157     uint64_t offs = xc->getSyscallArg(1);
 158     int whence = xc->getSyscallArg(2);
 159
 160     off_t result = lseek(fd, offs, whence);
 161
 162     return (result == (off_t)-1) ? -errno : result;
 163 }
 164
 165
 166 SyscallReturn
 167 munmapFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 168 {
 169     // given that we don't really implement mmap, munmap is really easy
 170     return 0;
 171 }
 172
 173
 174 const char *hostname = "m5.eecs.umich.edu";
 175
 176 SyscallReturn
 177 gethostnameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 178 {
 179     int name_len = xc->getSyscallArg(1);
 180     BufferArg name(xc->getSyscallArg(0), name_len);
 181
 182     strncpy((char *)name.bufferPtr(), hostname, name_len);
 183
 184     name.copyOut(xc->mem);
 185
 186     return 0;
 187 }
 188
 189 SyscallReturn
 190 unlinkFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 191 {
 192     string path;
 193
 194     if (xc->mem->readString(path, xc->getSyscallArg(0)) != No_Fault)
 195         return (TheISA::IntReg)-EFAULT;
 196
 197     int result = unlink(path.c_str());
 198     return (result == -1) ? -errno : result;
 199 }
 200
 201 SyscallReturn
 202 renameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 203 {
 204     string old_name;
 205
 206     if (xc->mem->readString(old_name, xc->getSyscallArg(0)) != No_Fault)
 207         return -EFAULT;
 208
 209     string new_name;
 210
 211     if (xc->mem->readString(new_name, xc->getSyscallArg(1)) != No_Fault)
 212         return -EFAULT;
 213
 214     int64_t result = rename(old_name.c_str(), new_name.c_str());
 215     return (result == -1) ? -errno : result;
 216 }
 217
 218 SyscallReturn
 219 truncateFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 220 {
 221     string path;
 222
 223     if (xc->mem->readString(path, xc->getSyscallArg(0)) != No_Fault)
 224         return -EFAULT;
 225
 226     off_t length = xc->getSyscallArg(1);
 227
 228     int result = truncate(path.c_str(), length);
 229     return (result == -1) ? -errno : result;
 230 }
 231
 232 SyscallReturn
 233 ftruncateFunc(SyscallDesc *desc, int num, Process *process, ExecContext *xc)
 234 {
 235     int fd = process->sim_fd(xc->getSyscallArg(0));
 236
 237     if (fd < 0)
 238         return -EBADF;
 239
 240     off_t length = xc->getSyscallArg(1);
 241
 242     int result = ftruncate(fd, length);
 243     return (result == -1) ? -errno : result;
 244 }
 245
 246 SyscallReturn
 247 chownFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 248 {
 249     string path;
 250
 251     if (xc->mem->readString(path, xc->getSyscallArg(0)) != No_Fault)
 252         return -EFAULT;
 253
 254     /* XXX endianess */
 255     uint32_t owner = xc->getSyscallArg(1);
 256     uid_t hostOwner = owner;
 257     uint32_t group = xc->getSyscallArg(2);
 258     gid_t hostGroup = group;
 259
 260     int result = chown(path.c_str(), hostOwner, hostGroup);
 261     return (result == -1) ? -errno : result;
 262 }
 263
 264 SyscallReturn
 265 fchownFunc(SyscallDesc *desc, int num, Process *process, ExecContext *xc)
 266 {
 267     int fd = process->sim_fd(xc->getSyscallArg(0));
 268
 269     if (fd < 0)
 270         return -EBADF;
 271
 272     /* XXX endianess */
 273     uint32_t owner = xc->getSyscallArg(1);
 274     uid_t hostOwner = owner;
 275     uint32_t group = xc->getSyscallArg(2);
 276     gid_t hostGroup = group;
 277
 278     int result = fchown(fd, hostOwner, hostGroup);
 279     return (result == -1) ? -errno : result;
 280 }