sim/syscall_emul.cc

   1 /*
   2  * Copyright (c) 2003-2004 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_cpu.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     int retval = (*funcPtr)(this, callnum, process, xc);
  51
  52     DPRINTFR(SyscallVerbose, "%s: syscall %s returns %d\n",
  53              xc->cpu->name(), name, retval);
  54
  55     if (!((flags & SyscallDesc::SuppressReturnValue) && retval == 0))
  56         xc->setSyscallReturn(retval);
  57 }
  58
  59
  60 int
  61 unimplementedFunc(SyscallDesc *desc, int callnum, Process *process,
  62                   ExecContext *xc)
  63 {
  64     cerr << "Error: syscall " << desc->name
  65          << " (#" << callnum << ") unimplemented.";
  66     cerr << "  Args: " << xc->getSyscallArg(0) << ", " << xc->getSyscallArg(1)
  67          << ", ..." << endl;
  68
  69     abort();
  70 }
  71
  72
  73 int
  74 ignoreFunc(SyscallDesc *desc, int callnum, Process *process,
  75            ExecContext *xc)
  76 {
  77     DCOUT(SyscallWarnings) << "Warning: ignoring syscall " << desc->name
  78                            << "(" << xc->getSyscallArg(0)
  79                            << ", " << xc->getSyscallArg(1)
  80                            << ", ...)" << endl;
  81
  82     return 0;
  83 }
  84
  85
  86 int
  87 exitFunc(SyscallDesc *desc, int callnum, Process *process,
  88          ExecContext *xc)
  89 {
  90     new SimExitEvent("syscall caused exit", xc->getSyscallArg(0) & 0xff);
  91
  92     return 1;
  93 }
  94
  95
  96 int
  97 getpagesizeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
  98 {
  99     return VMPageSize;
 100 }
 101
 102
 103 int
 104 obreakFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 105 {
 106     // change brk addr to first arg
 107     Addr new_brk = xc->getSyscallArg(0);
 108     if (new_brk != 0)
 109         p->brk_point = xc->getSyscallArg(0);
 110     return p->brk_point;
 111 }
 112
 113
 114 int
 115 closeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 116 {
 117     int fd = p->sim_fd(xc->getSyscallArg(0));
 118     return close(fd);
 119 }
 120
 121
 122 int
 123 readFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 124 {
 125     int fd = p->sim_fd(xc->getSyscallArg(0));
 126     int nbytes = xc->getSyscallArg(2);
 127     BufferArg bufArg(xc->getSyscallArg(1), nbytes);
 128
 129     int bytes_read = read(fd, bufArg.bufferPtr(), nbytes);
 130
 131     if (bytes_read != -1)
 132         bufArg.copyOut(xc->mem);
 133
 134     return bytes_read;
 135 }
 136
 137 int
 138 writeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 139 {
 140     int fd = p->sim_fd(xc->getSyscallArg(0));
 141     int nbytes = xc->getSyscallArg(2);
 142     BufferArg bufArg(xc->getSyscallArg(1), nbytes);
 143
 144     bufArg.copyIn(xc->mem);
 145
 146     int bytes_written = write(fd, bufArg.bufferPtr(), nbytes);
 147
 148     fsync(fd);
 149
 150     return bytes_written;
 151 }
 152
 153
 154 int
 155 lseekFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 156 {
 157     int fd = p->sim_fd(xc->getSyscallArg(0));
 158     uint64_t offs = xc->getSyscallArg(1);
 159     int whence = xc->getSyscallArg(2);
 160
 161     off_t result = lseek(fd, offs, whence);
 162
 163     return (result == (off_t)-1) ? -errno : result;
 164 }
 165
 166
 167 int
 168 munmapFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 169 {
 170     // given that we don't really implement mmap, munmap is really easy
 171     return 0;
 172 }
 173
 174
 175 const char *hostname = "m5.eecs.umich.edu";
 176
 177 int
 178 gethostnameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 179 {
 180     int name_len = xc->getSyscallArg(1);
 181     BufferArg name(xc->getSyscallArg(0), name_len);
 182
 183     strncpy((char *)name.bufferPtr(), hostname, name_len);
 184
 185     name.copyOut(xc->mem);
 186
 187     return 0;
 188 }
 189
 190 int
 191 unlinkFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 192 {
 193     std::string path;
 194
 195     if (xc->mem->readString(path, xc->getSyscallArg(0)) != No_Fault)
 196         return -EFAULT;
 197
 198     int result = unlink(path.c_str());
 199     return (result == -1) ? -errno : result;
 200 }
 201
 202 int
 203 renameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
 204 {
 205     std::string old_name;
 206
 207     if (xc->mem->readString(old_name, xc->getSyscallArg(0)) != No_Fault)
 208         return -EFAULT;
 209
 210     std::string new_name;
 211
 212     if (xc->mem->readString(new_name, xc->getSyscallArg(1)) != No_Fault)
 213         return -EFAULT;
 214
 215     int result = rename(old_name.c_str(),new_name.c_str());
 216     return (result == -1) ? -errno : result;
 217 }
 218