syscall_emul.hh revision 3277 
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 * Authors: Steve Reinhardt
29 *          Kevin Lim
30 */
31
32#ifndef __SIM_SYSCALL_EMUL_HH__
33#define __SIM_SYSCALL_EMUL_HH__
34
35#define NO_STAT64 (defined(__APPLE__) || defined(__OpenBSD__) || \
36                   defined(__FreeBSD__) || defined(__CYGWIN__))
37
38///
39/// @file syscall_emul.hh
40///
41/// This file defines objects used to emulate syscalls from the target
42/// application on the host machine.
43
44#include <errno.h>
45#include <string>
46#ifdef __CYGWIN32__
47#include <sys/fcntl.h>	// for O_BINARY
48#endif
49#include <sys/stat.h>
50#include <fcntl.h>
51#include <sys/uio.h>
52
53#include "sim/host.hh"	// for Addr
54#include "base/chunk_generator.hh"
55#include "base/intmath.hh"	// for RoundUp
56#include "base/misc.hh"
57#include "base/trace.hh"
58#include "cpu/base.hh"
59#include "cpu/thread_context.hh"
60#include "mem/translating_port.hh"
61#include "mem/page_table.hh"
62#include "sim/process.hh"
63
64///
65/// System call descriptor.
66///
67class SyscallDesc {
68
69  public:
70
71    /// Typedef for target syscall handler functions.
72    typedef SyscallReturn (*FuncPtr)(SyscallDesc *, int num,
73                           LiveProcess *, ThreadContext *);
74
75    const char *name;	//!< Syscall name (e.g., "open").
76    FuncPtr funcPtr;	//!< Pointer to emulation function.
77    int flags;		//!< Flags (see Flags enum).
78
79    /// Flag values for controlling syscall behavior.
80    enum Flags {
81        /// Don't set return regs according to funcPtr return value.
82        /// Used for syscalls with non-standard return conventions
83        /// that explicitly set the ThreadContext regs (e.g.,
84        /// sigreturn).
85        SuppressReturnValue = 1
86    };
87
88    /// Constructor.
89    SyscallDesc(const char *_name, FuncPtr _funcPtr, int _flags = 0)
90        : name(_name), funcPtr(_funcPtr), flags(_flags)
91    {
92    }
93
94    /// Emulate the syscall.  Public interface for calling through funcPtr.
95    void doSyscall(int callnum, LiveProcess *proc, ThreadContext *tc);
96};
97
98
99class BaseBufferArg {
100
101  public:
102
103    BaseBufferArg(Addr _addr, int _size) : addr(_addr), size(_size)
104    {
105        bufPtr = new uint8_t[size];
106        // clear out buffer: in case we only partially populate this,
107        // and then do a copyOut(), we want to make sure we don't
108        // introduce any random junk into the simulated address space
109        memset(bufPtr, 0, size);
110    }
111
112    virtual ~BaseBufferArg() { delete [] bufPtr; }
113
114    //
115    // copy data into simulator space (read from target memory)
116    //
117    virtual bool copyIn(TranslatingPort *memport)
118    {
119        memport->readBlob(addr, bufPtr, size);
120        return true;	// no EFAULT detection for now
121    }
122
123    //
124    // copy data out of simulator space (write to target memory)
125    //
126    virtual bool copyOut(TranslatingPort *memport)
127    {
128        memport->writeBlob(addr, bufPtr, size);
129        return true;	// no EFAULT detection for now
130    }
131
132  protected:
133    Addr addr;
134    int size;
135    uint8_t *bufPtr;
136};
137
138
139class BufferArg : public BaseBufferArg
140{
141  public:
142    BufferArg(Addr _addr, int _size) : BaseBufferArg(_addr, _size) { }
143    void *bufferPtr()	{ return bufPtr; }
144};
145
146template <class T>
147class TypedBufferArg : public BaseBufferArg
148{
149  public:
150    // user can optionally specify a specific number of bytes to
151    // allocate to deal with those structs that have variable-size
152    // arrays at the end
153    TypedBufferArg(Addr _addr, int _size = sizeof(T))
154        : BaseBufferArg(_addr, _size)
155    { }
156
157    // type case
158    operator T*() { return (T *)bufPtr; }
159
160    // dereference operators
161    T &operator*()	 { return *((T *)bufPtr); }
162    T* operator->()	 { return (T *)bufPtr; }
163    T &operator[](int i) { return ((T *)bufPtr)[i]; }
164};
165
166//////////////////////////////////////////////////////////////////////
167//
168// The following emulation functions are generic enough that they
169// don't need to be recompiled for different emulated OS's.  They are
170// defined in sim/syscall_emul.cc.
171//
172//////////////////////////////////////////////////////////////////////
173
174
175/// Handler for unimplemented syscalls that we haven't thought about.
176SyscallReturn unimplementedFunc(SyscallDesc *desc, int num,
177                                LiveProcess *p, ThreadContext *tc);
178
179/// Handler for unimplemented syscalls that we never intend to
180/// implement (signal handling, etc.) and should not affect the correct
181/// behavior of the program.  Print a warning only if the appropriate
182/// trace flag is enabled.  Return success to the target program.
183SyscallReturn ignoreFunc(SyscallDesc *desc, int num,
184                         LiveProcess *p, ThreadContext *tc);
185
186/// Target exit() handler: terminate simulation.
187SyscallReturn exitFunc(SyscallDesc *desc, int num,
188                       LiveProcess *p, ThreadContext *tc);
189
190/// Target getpagesize() handler.
191SyscallReturn getpagesizeFunc(SyscallDesc *desc, int num,
192                              LiveProcess *p, ThreadContext *tc);
193
194/// Target obreak() handler: set brk address.
195SyscallReturn obreakFunc(SyscallDesc *desc, int num,
196                         LiveProcess *p, ThreadContext *tc);
197
198/// Target close() handler.
199SyscallReturn closeFunc(SyscallDesc *desc, int num,
200                        LiveProcess *p, ThreadContext *tc);
201
202/// Target read() handler.
203SyscallReturn readFunc(SyscallDesc *desc, int num,
204                       LiveProcess *p, ThreadContext *tc);
205
206/// Target write() handler.
207SyscallReturn writeFunc(SyscallDesc *desc, int num,
208                        LiveProcess *p, ThreadContext *tc);
209
210/// Target lseek() handler.
211SyscallReturn lseekFunc(SyscallDesc *desc, int num,
212                        LiveProcess *p, ThreadContext *tc);
213
214/// Target munmap() handler.
215SyscallReturn munmapFunc(SyscallDesc *desc, int num,
216                         LiveProcess *p, ThreadContext *tc);
217
218/// Target gethostname() handler.
219SyscallReturn gethostnameFunc(SyscallDesc *desc, int num,
220                              LiveProcess *p, ThreadContext *tc);
221
222/// Target unlink() handler.
223SyscallReturn unlinkFunc(SyscallDesc *desc, int num,
224                         LiveProcess *p, ThreadContext *tc);
225
226/// Target rename() handler.
227SyscallReturn renameFunc(SyscallDesc *desc, int num,
228                         LiveProcess *p, ThreadContext *tc);
229
230
231/// Target truncate() handler.
232SyscallReturn truncateFunc(SyscallDesc *desc, int num,
233                           LiveProcess *p, ThreadContext *tc);
234
235
236/// Target ftruncate() handler.
237SyscallReturn ftruncateFunc(SyscallDesc *desc, int num,
238                            LiveProcess *p, ThreadContext *tc);
239
240
241/// Target chown() handler.
242SyscallReturn chownFunc(SyscallDesc *desc, int num,
243                        LiveProcess *p, ThreadContext *tc);
244
245
246/// Target fchown() handler.
247SyscallReturn fchownFunc(SyscallDesc *desc, int num,
248                         LiveProcess *p, ThreadContext *tc);
249
250/// Target dup() handler.
251SyscallReturn dupFunc(SyscallDesc *desc, int num,
252                      LiveProcess *process, ThreadContext *tc);
253
254/// Target fnctl() handler.
255SyscallReturn fcntlFunc(SyscallDesc *desc, int num,
256                        LiveProcess *process, ThreadContext *tc);
257
258/// Target fcntl64() handler.
259SyscallReturn fcntl64Func(SyscallDesc *desc, int num,
260                        LiveProcess *process, ThreadContext *tc);
261
262/// Target setuid() handler.
263SyscallReturn setuidFunc(SyscallDesc *desc, int num,
264                               LiveProcess *p, ThreadContext *tc);
265
266/// Target getpid() handler.
267SyscallReturn getpidFunc(SyscallDesc *desc, int num,
268                               LiveProcess *p, ThreadContext *tc);
269
270/// Target getuid() handler.
271SyscallReturn getuidFunc(SyscallDesc *desc, int num,
272                               LiveProcess *p, ThreadContext *tc);
273
274/// Target getgid() handler.
275SyscallReturn getgidFunc(SyscallDesc *desc, int num,
276                               LiveProcess *p, ThreadContext *tc);
277
278/// Target getppid() handler.
279SyscallReturn getppidFunc(SyscallDesc *desc, int num,
280                               LiveProcess *p, ThreadContext *tc);
281
282/// Target geteuid() handler.
283SyscallReturn geteuidFunc(SyscallDesc *desc, int num,
284                               LiveProcess *p, ThreadContext *tc);
285
286/// Target getegid() handler.
287SyscallReturn getegidFunc(SyscallDesc *desc, int num,
288                               LiveProcess *p, ThreadContext *tc);
289
290
291
292/// Pseudo Funcs  - These functions use a different return convension,
293/// returning a second value in a register other than the normal return register
294SyscallReturn pipePseudoFunc(SyscallDesc *desc, int num,
295                             LiveProcess *process, ThreadContext *tc);
296
297/// Target getpidPseudo() handler.
298SyscallReturn getpidPseudoFunc(SyscallDesc *desc, int num,
299                               LiveProcess *p, ThreadContext *tc);
300
301/// Target getuidPseudo() handler.
302SyscallReturn getuidPseudoFunc(SyscallDesc *desc, int num,
303                               LiveProcess *p, ThreadContext *tc);
304
305/// Target getgidPseudo() handler.
306SyscallReturn getgidPseudoFunc(SyscallDesc *desc, int num,
307                               LiveProcess *p, ThreadContext *tc);
308
309
310/// A readable name for 1,000,000, for converting microseconds to seconds.
311const int one_million = 1000000;
312
313/// Approximate seconds since the epoch (1/1/1970).  About a billion,
314/// by my reckoning.  We want to keep this a constant (not use the
315/// real-world time) to keep simulations repeatable.
316const unsigned seconds_since_epoch = 1000000000;
317
318/// Helper function to convert current elapsed time to seconds and
319/// microseconds.
320template <class T1, class T2>
321void
322getElapsedTime(T1 &sec, T2 &usec)
323{
324    int elapsed_usecs = curTick / Clock::Int::us;
325    sec = elapsed_usecs / one_million;
326    usec = elapsed_usecs % one_million;
327}
328
329//////////////////////////////////////////////////////////////////////
330//
331// The following emulation functions are generic, but need to be
332// templated to account for differences in types, constants, etc.
333//
334//////////////////////////////////////////////////////////////////////
335
336#if NO_STAT64
337    typedef struct stat hst_stat;
338    typedef struct stat hst_stat64;
339#else
340    typedef struct stat hst_stat;
341    typedef struct stat64 hst_stat64;
342#endif
343
344//// Helper function to convert a host stat buffer to a target stat
345//// buffer.  Also copies the target buffer out to the simulated
346//// memory space.  Used by stat(), fstat(), and lstat().
347
348template <typename target_stat, typename host_stat>
349static void
350convertStatBuf(target_stat &tgt, host_stat *host, bool fakeTTY = false)
351{
352    if (fakeTTY)
353        tgt->st_dev = 0xA;
354    else
355        tgt->st_dev = host->st_dev;
356    tgt->st_dev = htog(tgt->st_dev);
357    tgt->st_ino = host->st_ino;
358    tgt->st_ino = htog(tgt->st_ino);
359    tgt->st_mode = host->st_mode;
360    tgt->st_mode = htog(tgt->st_mode);
361    tgt->st_nlink = host->st_nlink;
362    tgt->st_nlink = htog(tgt->st_nlink);
363    tgt->st_uid = host->st_uid;
364    tgt->st_uid = htog(tgt->st_uid);
365    tgt->st_gid = host->st_gid;
366    tgt->st_gid = htog(tgt->st_gid);
367    if (fakeTTY)
368        tgt->st_rdev = 0x880d;
369    else
370        tgt->st_rdev = host->st_rdev;
371    tgt->st_rdev = htog(tgt->st_rdev);
372    tgt->st_size = host->st_size;
373    tgt->st_size = htog(tgt->st_size);
374    tgt->st_atimeX = host->st_atime;
375    tgt->st_atimeX = htog(tgt->st_atimeX);
376    tgt->st_mtimeX = host->st_mtime;
377    tgt->st_mtimeX = htog(tgt->st_mtimeX);
378    tgt->st_ctimeX = host->st_ctime;
379    tgt->st_ctimeX = htog(tgt->st_ctimeX);
380    tgt->st_blksize = host->st_blksize;
381    tgt->st_blksize = htog(tgt->st_blksize);
382    tgt->st_blocks = host->st_blocks;
383    tgt->st_blocks = htog(tgt->st_blocks);
384}
385
386// Same for stat64
387
388template <typename target_stat, typename host_stat64>
389static void
390convertStat64Buf(target_stat &tgt, host_stat64 *host, bool fakeTTY = false)
391{
392    convertStatBuf<target_stat, host_stat64>(tgt, host, fakeTTY);
393#if defined(STAT_HAVE_NSEC)
394    tgt->st_atime_nsec = host->st_atime_nsec;
395    tgt->st_atime_nsec = htog(tgt->st_atime_nsec);
396    tgt->st_mtime_nsec = host->st_mtime_nsec;
397    tgt->st_mtime_nsec = htog(tgt->st_mtime_nsec);
398    tgt->st_ctime_nsec = host->st_ctime_nsec;
399    tgt->st_ctime_nsec = htog(tgt->st_ctime_nsec);
400#else
401    tgt->st_atime_nsec = 0;
402    tgt->st_mtime_nsec = 0;
403    tgt->st_ctime_nsec = 0;
404#endif
405}
406
407//Here are a couple convenience functions
408template<class OS>
409static void
410copyOutStatBuf(TranslatingPort * mem, Addr addr,
411        hst_stat *host, bool fakeTTY = false)
412{
413    typedef TypedBufferArg<typename OS::tgt_stat> tgt_stat_buf;
414    tgt_stat_buf tgt(addr);
415    convertStatBuf<tgt_stat_buf, hst_stat>(tgt, host, fakeTTY);
416    tgt.copyOut(mem);
417}
418
419template<class OS>
420static void
421copyOutStat64Buf(TranslatingPort * mem, Addr addr,
422        hst_stat64 *host, bool fakeTTY = false)
423{
424    typedef TypedBufferArg<typename OS::tgt_stat64> tgt_stat_buf;
425    tgt_stat_buf tgt(addr);
426    convertStatBuf<tgt_stat_buf, hst_stat64>(tgt, host, fakeTTY);
427    tgt.copyOut(mem);
428}
429
430/// Target ioctl() handler.  For the most part, programs call ioctl()
431/// only to find out if their stdout is a tty, to determine whether to
432/// do line or block buffering.
433template <class OS>
434SyscallReturn
435ioctlFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
436          ThreadContext *tc)
437{
438    int fd = tc->getSyscallArg(0);
439    unsigned req = tc->getSyscallArg(1);
440
441    DPRINTF(SyscallVerbose, "ioctl(%d, 0x%x, ...)\n", fd, req);
442
443    if (fd < 0 || process->sim_fd(fd) < 0) {
444        // doesn't map to any simulator fd: not a valid target fd
445        return -EBADF;
446    }
447
448    switch (req) {
449      case OS::TIOCISATTY:
450      case OS::TIOCGETP:
451      case OS::TIOCSETP:
452      case OS::TIOCSETN:
453      case OS::TIOCSETC:
454      case OS::TIOCGETC:
455      case OS::TIOCGETS:
456      case OS::TIOCGETA:
457        return -ENOTTY;
458
459      default:
460        fatal("Unsupported ioctl call: ioctl(%d, 0x%x, ...) @ 0x%llx\n",
461              fd, req, tc->readPC());
462    }
463}
464
465/// Target open() handler.
466template <class OS>
467SyscallReturn
468openFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
469         ThreadContext *tc)
470{
471    std::string path;
472
473    if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
474        return -EFAULT;
475
476    if (path == "/dev/sysdev0") {
477        // This is a memory-mapped high-resolution timer device on Alpha.
478        // We don't support it, so just punt.
479        warn("Ignoring open(%s, ...)\n", path);
480        return -ENOENT;
481    }
482
483    int tgtFlags = tc->getSyscallArg(1);
484    int mode = tc->getSyscallArg(2);
485    int hostFlags = 0;
486
487    // translate open flags
488    for (int i = 0; i < OS::NUM_OPEN_FLAGS; i++) {
489        if (tgtFlags & OS::openFlagTable[i].tgtFlag) {
490            tgtFlags &= ~OS::openFlagTable[i].tgtFlag;
491            hostFlags |= OS::openFlagTable[i].hostFlag;
492        }
493    }
494
495    // any target flags left?
496    if (tgtFlags != 0)
497        warn("Syscall: open: cannot decode flags 0x%x", tgtFlags);
498
499#ifdef __CYGWIN32__
500    hostFlags |= O_BINARY;
501#endif
502
503    DPRINTF(SyscallVerbose, "opening file %s\n", path.c_str());
504
505    // open the file
506    int fd = open(path.c_str(), hostFlags, mode);
507
508    return (fd == -1) ? -errno : process->alloc_fd(fd);
509}
510
511
512/// Target chmod() handler.
513template <class OS>
514SyscallReturn
515chmodFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
516          ThreadContext *tc)
517{
518    std::string path;
519
520    if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
521        return -EFAULT;
522
523    uint32_t mode = tc->getSyscallArg(1);
524    mode_t hostMode = 0;
525
526    // XXX translate mode flags via OS::something???
527    hostMode = mode;
528
529    // do the chmod
530    int result = chmod(path.c_str(), hostMode);
531    if (result < 0)
532        return -errno;
533
534    return 0;
535}
536
537
538/// Target fchmod() handler.
539template <class OS>
540SyscallReturn
541fchmodFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
542           ThreadContext *tc)
543{
544    int fd = tc->getSyscallArg(0);
545    if (fd < 0 || process->sim_fd(fd) < 0) {
546        // doesn't map to any simulator fd: not a valid target fd
547        return -EBADF;
548    }
549
550    uint32_t mode = tc->getSyscallArg(1);
551    mode_t hostMode = 0;
552
553    // XXX translate mode flags via OS::someting???
554    hostMode = mode;
555
556    // do the fchmod
557    int result = fchmod(process->sim_fd(fd), hostMode);
558    if (result < 0)
559        return -errno;
560
561    return 0;
562}
563
564
565/// Target stat() handler.
566template <class OS>
567SyscallReturn
568statFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
569         ThreadContext *tc)
570{
571    std::string path;
572
573    if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
574    return -EFAULT;
575
576    struct stat hostBuf;
577    int result = stat(path.c_str(), &hostBuf);
578
579    if (result < 0)
580        return -errno;
581
582    copyOutStatBuf<OS>(tc->getMemPort(), tc->getSyscallArg(1), &hostBuf);
583
584    return 0;
585}
586
587
588/// Target fstat64() handler.
589template <class OS>
590SyscallReturn
591fstat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
592            ThreadContext *tc)
593{
594    int fd = tc->getSyscallArg(0);
595    if (fd < 0 || process->sim_fd(fd) < 0) {
596        // doesn't map to any simulator fd: not a valid target fd
597        return -EBADF;
598    }
599
600#if NO_STAT64
601    struct stat  hostBuf;
602    int result = fstat(process->sim_fd(fd), &hostBuf);
603#else
604    struct stat64  hostBuf;
605    int result = fstat64(process->sim_fd(fd), &hostBuf);
606#endif
607
608    if (result < 0)
609        return -errno;
610
611    copyOutStat64Buf<OS>(tc->getMemPort(), tc->getSyscallArg(1),
612        &hostBuf, (fd == 1));
613
614    return 0;
615}
616
617
618/// Target lstat() handler.
619template <class OS>
620SyscallReturn
621lstatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
622          ThreadContext *tc)
623{
624    std::string path;
625
626    if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
627      return -EFAULT;
628
629    struct stat hostBuf;
630    int result = lstat(path.c_str(), &hostBuf);
631
632    if (result < 0)
633        return -errno;
634
635    copyOutStatBuf<OS>(tc->getMemPort(), tc->getSyscallArg(1), &hostBuf);
636
637    return 0;
638}
639
640/// Target lstat64() handler.
641template <class OS>
642SyscallReturn
643lstat64Func(SyscallDesc *desc, int callnum, LiveProcess *process,
644            ThreadContext *tc)
645{
646    std::string path;
647
648    if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
649      return -EFAULT;
650
651#if NO_STAT64
652    struct stat hostBuf;
653    int result = lstat(path.c_str(), &hostBuf);
654#else
655    struct stat64 hostBuf;
656    int result = lstat64(path.c_str(), &hostBuf);
657#endif
658
659    if (result < 0)
660        return -errno;
661
662    copyOutStat64Buf<OS>(tc->getMemPort(), tc->getSyscallArg(1), &hostBuf);
663
664    return 0;
665}
666
667/// Target fstat() handler.
668template <class OS>
669SyscallReturn
670fstatFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
671          ThreadContext *tc)
672{
673    int fd = process->sim_fd(tc->getSyscallArg(0));
674
675    DPRINTF(SyscallVerbose, "fstat(%d, ...)\n", fd);
676
677    if (fd < 0)
678        return -EBADF;
679
680    struct stat hostBuf;
681    int result = fstat(fd, &hostBuf);
682
683    if (result < 0)
684        return -errno;
685
686    copyOutStatBuf<OS>(tc->getMemPort(), tc->getSyscallArg(1),
687        &hostBuf, (fd == 1));
688
689    return 0;
690}
691
692
693/// Target statfs() handler.
694template <class OS>
695SyscallReturn
696statfsFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
697           ThreadContext *tc)
698{
699    std::string path;
700
701    if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
702      return -EFAULT;
703
704    struct statfs hostBuf;
705    int result = statfs(path.c_str(), &hostBuf);
706
707    if (result < 0)
708        return -errno;
709
710    OS::copyOutStatfsBuf(tc->getMemPort(),
711            (Addr)(tc->getSyscallArg(1)), &hostBuf);
712
713    return 0;
714}
715
716
717/// Target fstatfs() handler.
718template <class OS>
719SyscallReturn
720fstatfsFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
721            ThreadContext *tc)
722{
723    int fd = process->sim_fd(tc->getSyscallArg(0));
724
725    if (fd < 0)
726        return -EBADF;
727
728    struct statfs hostBuf;
729    int result = fstatfs(fd, &hostBuf);
730
731    if (result < 0)
732        return -errno;
733
734    OS::copyOutStatfsBuf(tc->getMemPort(), tc->getSyscallArg(1),
735        &hostBuf);
736
737    return 0;
738}
739
740
741/// Target writev() handler.
742template <class OS>
743SyscallReturn
744writevFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
745           ThreadContext *tc)
746{
747    int fd = tc->getSyscallArg(0);
748    if (fd < 0 || process->sim_fd(fd) < 0) {
749        // doesn't map to any simulator fd: not a valid target fd
750        return -EBADF;
751    }
752
753    TranslatingPort *p = tc->getMemPort();
754    uint64_t tiov_base = tc->getSyscallArg(1);
755    size_t count = tc->getSyscallArg(2);
756    struct iovec hiov[count];
757    for (int i = 0; i < count; ++i)
758    {
759        typename OS::tgt_iovec tiov;
760
761        p->readBlob(tiov_base + i*sizeof(typename OS::tgt_iovec),
762                    (uint8_t*)&tiov, sizeof(typename OS::tgt_iovec));
763        hiov[i].iov_len = gtoh(tiov.iov_len);
764        hiov[i].iov_base = new char [hiov[i].iov_len];
765        p->readBlob(gtoh(tiov.iov_base), (uint8_t *)hiov[i].iov_base,
766                    hiov[i].iov_len);
767    }
768
769    int result = writev(process->sim_fd(fd), hiov, count);
770
771    for (int i = 0; i < count; ++i)
772    {
773        delete [] (char *)hiov[i].iov_base;
774    }
775
776    if (result < 0)
777        return -errno;
778
779    return 0;
780}
781
782
783/// Target mmap() handler.
784///
785/// We don't really handle mmap().  If the target is mmaping an
786/// anonymous region or /dev/zero, we can get away with doing basically
787/// nothing (since memory is initialized to zero and the simulator
788/// doesn't really check addresses anyway).  Always print a warning,
789/// since this could be seriously broken if we're not mapping
790/// /dev/zero.
791//
792/// Someday we should explicitly check for /dev/zero in open, flag the
793/// file descriptor, and fail (or implement!) a non-anonymous mmap to
794/// anything else.
795template <class OS>
796SyscallReturn
797mmapFunc(SyscallDesc *desc, int num, LiveProcess *p, ThreadContext *tc)
798{
799    Addr start = tc->getSyscallArg(0);
800    uint64_t length = tc->getSyscallArg(1);
801    // int prot = tc->getSyscallArg(2);
802    int flags = tc->getSyscallArg(3);
803    // int fd = p->sim_fd(tc->getSyscallArg(4));
804    // int offset = tc->getSyscallArg(5);
805
806    if ((start  % TheISA::VMPageSize) != 0 ||
807        (length % TheISA::VMPageSize) != 0) {
808        warn("mmap failing: arguments not page-aligned: "
809             "start 0x%x length 0x%x",
810             start, length);
811        return -EINVAL;
812    }
813
814    if (start != 0) {
815        warn("mmap: ignoring suggested map address 0x%x, using 0x%x",
816             start, p->mmap_end);
817    }
818
819    // pick next address from our "mmap region"
820    start = p->mmap_end;
821    p->pTable->allocate(start, length);
822    p->mmap_end += length;
823
824    if (!(flags & OS::TGT_MAP_ANONYMOUS)) {
825        warn("allowing mmap of file @ fd %d. "
826             "This will break if not /dev/zero.", tc->getSyscallArg(4));
827    }
828
829    return start;
830}
831
832/// Target getrlimit() handler.
833template <class OS>
834SyscallReturn
835getrlimitFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
836        ThreadContext *tc)
837{
838    unsigned resource = tc->getSyscallArg(0);
839    TypedBufferArg<typename OS::rlimit> rlp(tc->getSyscallArg(1));
840
841    switch (resource) {
842        case OS::TGT_RLIMIT_STACK:
843            // max stack size in bytes: make up a number (2MB for now)
844            rlp->rlim_cur = rlp->rlim_max = 8 * 1024 * 1024;
845            rlp->rlim_cur = htog(rlp->rlim_cur);
846            rlp->rlim_max = htog(rlp->rlim_max);
847            break;
848
849        default:
850            std::cerr << "getrlimitFunc: unimplemented resource " << resource
851                << std::endl;
852            abort();
853            break;
854    }
855
856    rlp.copyOut(tc->getMemPort());
857    return 0;
858}
859
860/// Target gettimeofday() handler.
861template <class OS>
862SyscallReturn
863gettimeofdayFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
864        ThreadContext *tc)
865{
866    TypedBufferArg<typename OS::timeval> tp(tc->getSyscallArg(0));
867
868    getElapsedTime(tp->tv_sec, tp->tv_usec);
869    tp->tv_sec += seconds_since_epoch;
870    tp->tv_sec = htog(tp->tv_sec);
871    tp->tv_usec = htog(tp->tv_usec);
872
873    tp.copyOut(tc->getMemPort());
874
875    return 0;
876}
877
878
879/// Target utimes() handler.
880template <class OS>
881SyscallReturn
882utimesFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
883           ThreadContext *tc)
884{
885    std::string path;
886
887    if (!tc->getMemPort()->tryReadString(path, tc->getSyscallArg(0)))
888      return -EFAULT;
889
890    TypedBufferArg<typename OS::timeval [2]> tp(tc->getSyscallArg(1));
891    tp.copyIn(tc->getMemPort());
892
893    struct timeval hostTimeval[2];
894    for (int i = 0; i < 2; ++i)
895    {
896        hostTimeval[i].tv_sec = gtoh((*tp)[i].tv_sec);
897        hostTimeval[i].tv_usec = gtoh((*tp)[i].tv_usec);
898    }
899    int result = utimes(path.c_str(), hostTimeval);
900
901    if (result < 0)
902        return -errno;
903
904    return 0;
905}
906/// Target getrusage() function.
907template <class OS>
908SyscallReturn
909getrusageFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
910              ThreadContext *tc)
911{
912    int who = tc->getSyscallArg(0);	// THREAD, SELF, or CHILDREN
913    TypedBufferArg<typename OS::rusage> rup(tc->getSyscallArg(1));
914
915    if (who != OS::TGT_RUSAGE_SELF) {
916        // don't really handle THREAD or CHILDREN, but just warn and
917        // plow ahead
918        warn("getrusage() only supports RUSAGE_SELF.  Parameter %d ignored.",
919             who);
920    }
921
922    getElapsedTime(rup->ru_utime.tv_sec, rup->ru_utime.tv_usec);
923    rup->ru_utime.tv_sec = htog(rup->ru_utime.tv_sec);
924    rup->ru_utime.tv_usec = htog(rup->ru_utime.tv_usec);
925
926    rup->ru_stime.tv_sec = 0;
927    rup->ru_stime.tv_usec = 0;
928    rup->ru_maxrss = 0;
929    rup->ru_ixrss = 0;
930    rup->ru_idrss = 0;
931    rup->ru_isrss = 0;
932    rup->ru_minflt = 0;
933    rup->ru_majflt = 0;
934    rup->ru_nswap = 0;
935    rup->ru_inblock = 0;
936    rup->ru_oublock = 0;
937    rup->ru_msgsnd = 0;
938    rup->ru_msgrcv = 0;
939    rup->ru_nsignals = 0;
940    rup->ru_nvcsw = 0;
941    rup->ru_nivcsw = 0;
942
943    rup.copyOut(tc->getMemPort());
944
945    return 0;
946}
947
948
949
950
951#endif // __SIM_SYSCALL_EMUL_HH__
952