syscall_emul.cc revision 511 
1/*
2 * Copyright (c) 2003 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
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    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
60int
61unimplementedFunc(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
73int
74ignoreFunc(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
86int
87exitFunc(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
96int
97getpagesizeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
98{
99    return VMPageSize;
100}
101
102
103int
104obreakFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
105{
106    // change brk addr to first arg
107    p->brk_point = xc->getSyscallArg(0);
108    return p->brk_point;
109}
110
111
112int
113closeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
114{
115    int fd = p->sim_fd(xc->getSyscallArg(0));
116    return close(fd);
117}
118
119
120int
121readFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
122{
123    int fd = p->sim_fd(xc->getSyscallArg(0));
124    int nbytes = xc->getSyscallArg(2);
125    BufferArg bufArg(xc->getSyscallArg(1), nbytes);
126
127    int bytes_read = read(fd, bufArg.bufferPtr(), nbytes);
128
129    if (bytes_read != -1)
130        bufArg.copyOut(xc->mem);
131
132    return bytes_read;
133}
134
135int
136writeFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
137{
138    int fd = p->sim_fd(xc->getSyscallArg(0));
139    int nbytes = xc->getSyscallArg(2);
140    BufferArg bufArg(xc->getSyscallArg(1), nbytes);
141
142    bufArg.copyIn(xc->mem);
143
144    int bytes_written = write(fd, bufArg.bufferPtr(), nbytes);
145
146    fsync(fd);
147
148    return bytes_written;
149}
150
151
152int
153lseekFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
154{
155    int fd = p->sim_fd(xc->getSyscallArg(0));
156    uint64_t offs = xc->getSyscallArg(1);
157    int whence = xc->getSyscallArg(2);
158
159    off_t result = lseek(fd, offs, whence);
160
161    return (result == (off_t)-1) ? -errno : result;
162}
163
164
165int
166munmapFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
167{
168    // given that we don't really implement mmap, munmap is really easy
169    return 0;
170}
171
172
173const char *hostname = "m5.eecs.umich.edu";
174
175int
176gethostnameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
177{
178    int name_len = xc->getSyscallArg(1);
179    BufferArg name(xc->getSyscallArg(0), name_len);
180
181    strncpy((char *)name.bufferPtr(), hostname, name_len);
182
183    name.copyOut(xc->mem);
184
185    return 0;
186}
187
188int
189unlinkFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
190{
191    std::string path;
192
193    if (xc->mem->readString(path, xc->getSyscallArg(0)) != No_Fault)
194        return -EFAULT;
195
196    int result = unlink(path.c_str());
197    return (result == -1) ? -errno : result;
198}
199
200int
201renameFunc(SyscallDesc *desc, int num, Process *p, ExecContext *xc)
202{
203    std::string old_name;
204
205    if (xc->mem->readString(old_name, xc->getSyscallArg(0)) != No_Fault)
206        return -EFAULT;
207
208    std::string new_name;
209
210    if (xc->mem->readString(new_name, xc->getSyscallArg(1)) != No_Fault)
211        return -EFAULT;
212
213    int result = rename(old_name.c_str(),new_name.c_str());
214    return (result == -1) ? -errno : result;
215}
216
217