1/* Replay a remote debug session logfile for GDB.
2   Copyright (C) 1996-2020 Free Software Foundation, Inc.
3   Written by Fred Fish (fnf@cygnus.com) from pieces of gdbserver.
4
5   This file is part of GDB.
6
7   This program is free software; you can redistribute it and/or modify
8   it under the terms of the GNU General Public License as published by
9   the Free Software Foundation; either version 3 of the License, or
10   (at your option) any later version.
11
12   This program is distributed in the hope that it will be useful,
13   but WITHOUT ANY WARRANTY; without even the implied warranty of
14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15   GNU General Public License for more details.
16
17   You should have received a copy of the GNU General Public License
18   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19
20#include "gdbsupport/common-defs.h"
21
22#undef PACKAGE
23#undef PACKAGE_NAME
24#undef PACKAGE_VERSION
25#undef PACKAGE_STRING
26#undef PACKAGE_TARNAME
27
28#include <config.h>
29#include "gdbsupport/version.h"
30
31#if HAVE_SYS_FILE_H
32#include <sys/file.h>
33#endif
34#if HAVE_SIGNAL_H
35#include <signal.h>
36#endif
37#include <ctype.h>
38#if HAVE_FCNTL_H
39#include <fcntl.h>
40#endif
41#include <unistd.h>
42#ifdef HAVE_NETINET_IN_H
43#include <netinet/in.h>
44#endif
45#ifdef HAVE_SYS_SOCKET_H
46#include <sys/socket.h>
47#endif
48#if HAVE_NETDB_H
49#include <netdb.h>
50#endif
51#if HAVE_NETINET_TCP_H
52#include <netinet/tcp.h>
53#endif
54
55#if USE_WIN32API
56#include <ws2tcpip.h>
57#endif
58
59#include "gdbsupport/netstuff.h"
60#include "gdbsupport/rsp-low.h"
61
62#ifndef HAVE_SOCKLEN_T
63typedef int socklen_t;
64#endif
65
66/* Sort of a hack... */
67#define EOL (EOF - 1)
68
69static int remote_desc;
70
71#ifdef __MINGW32CE__
72
73#ifndef COUNTOF
74#define COUNTOF(STR) (sizeof (STR) / sizeof ((STR)[0]))
75#endif
76
77#define errno (GetLastError ())
78
79char *
80strerror (DWORD error)
81{
82  static char buf[1024];
83  WCHAR *msgbuf;
84  DWORD lasterr = GetLastError ();
85  DWORD chars = FormatMessageW (FORMAT_MESSAGE_FROM_SYSTEM
86				| FORMAT_MESSAGE_ALLOCATE_BUFFER,
87				NULL,
88				error,
89				0, /* Default language */
90				(LPVOID)&msgbuf,
91				0,
92				NULL);
93  if (chars != 0)
94    {
95      /* If there is an \r\n appended, zap it.  */
96      if (chars >= 2
97	  && msgbuf[chars - 2] == '\r'
98	  && msgbuf[chars - 1] == '\n')
99	{
100	  chars -= 2;
101	  msgbuf[chars] = 0;
102	}
103
104      if (chars > ((COUNTOF (buf)) - 1))
105	{
106	  chars = COUNTOF (buf) - 1;
107	  msgbuf [chars] = 0;
108	}
109
110      wcstombs (buf, msgbuf, chars + 1);
111      LocalFree (msgbuf);
112    }
113  else
114    sprintf (buf, "unknown win32 error (%ld)", error);
115
116  SetLastError (lasterr);
117  return buf;
118}
119
120#endif /* __MINGW32CE__ */
121
122static void
123sync_error (FILE *fp, const char *desc, int expect, int got)
124{
125  fprintf (stderr, "\n%s\n", desc);
126  fprintf (stderr, "At logfile offset %ld, expected '0x%x' got '0x%x'\n",
127	   ftell (fp), expect, got);
128  fflush (stderr);
129  exit (1);
130}
131
132static void
133remote_error (const char *desc)
134{
135  fprintf (stderr, "\n%s\n", desc);
136  fflush (stderr);
137  exit (1);
138}
139
140static void
141remote_close (void)
142{
143#ifdef USE_WIN32API
144  closesocket (remote_desc);
145#else
146  close (remote_desc);
147#endif
148}
149
150/* Open a connection to a remote debugger.
151   NAME is the filename used for communication.  */
152
153static void
154remote_open (char *name)
155{
156  char *last_colon = strrchr (name, ':');
157
158  if (last_colon == NULL)
159    {
160      fprintf (stderr, "%s: Must specify tcp connection as host:addr\n", name);
161      fflush (stderr);
162      exit (1);
163    }
164
165#ifdef USE_WIN32API
166  static int winsock_initialized;
167#endif
168  int tmp;
169  int tmp_desc;
170  struct addrinfo hint;
171  struct addrinfo *ainfo;
172
173  memset (&hint, 0, sizeof (hint));
174  /* Assume no prefix will be passed, therefore we should use
175     AF_UNSPEC.  */
176  hint.ai_family = AF_UNSPEC;
177  hint.ai_socktype = SOCK_STREAM;
178  hint.ai_protocol = IPPROTO_TCP;
179
180  parsed_connection_spec parsed = parse_connection_spec (name, &hint);
181
182  if (parsed.port_str.empty ())
183    error (_("Missing port on hostname '%s'"), name);
184
185#ifdef USE_WIN32API
186  if (!winsock_initialized)
187    {
188      WSADATA wsad;
189
190      WSAStartup (MAKEWORD (1, 0), &wsad);
191      winsock_initialized = 1;
192    }
193#endif
194
195  int r = getaddrinfo (parsed.host_str.c_str (), parsed.port_str.c_str (),
196		       &hint, &ainfo);
197
198  if (r != 0)
199    {
200      fprintf (stderr, "%s:%s: cannot resolve name: %s\n",
201	       parsed.host_str.c_str (), parsed.port_str.c_str (),
202	       gai_strerror (r));
203      fflush (stderr);
204      exit (1);
205    }
206
207  scoped_free_addrinfo free_ainfo (ainfo);
208
209  struct addrinfo *p;
210
211  for (p = ainfo; p != NULL; p = p->ai_next)
212    {
213      tmp_desc = socket (p->ai_family, p->ai_socktype, p->ai_protocol);
214
215      if (tmp_desc >= 0)
216	break;
217    }
218
219  if (p == NULL)
220    perror_with_name ("Cannot open socket");
221
222  /* Allow rapid reuse of this port. */
223  tmp = 1;
224  setsockopt (tmp_desc, SOL_SOCKET, SO_REUSEADDR, (char *) &tmp,
225	      sizeof (tmp));
226
227  switch (p->ai_family)
228    {
229    case AF_INET:
230      ((struct sockaddr_in *) p->ai_addr)->sin_addr.s_addr = INADDR_ANY;
231      break;
232    case AF_INET6:
233      ((struct sockaddr_in6 *) p->ai_addr)->sin6_addr = in6addr_any;
234      break;
235    default:
236      fprintf (stderr, "Invalid 'ai_family' %d\n", p->ai_family);
237      exit (1);
238    }
239
240  if (bind (tmp_desc, p->ai_addr, p->ai_addrlen) != 0)
241    perror_with_name ("Can't bind address");
242
243  if (p->ai_socktype == SOCK_DGRAM)
244    remote_desc = tmp_desc;
245  else
246    {
247      struct sockaddr_storage sockaddr;
248      socklen_t sockaddrsize = sizeof (sockaddr);
249      char orig_host[GDB_NI_MAX_ADDR], orig_port[GDB_NI_MAX_PORT];
250
251      if (listen (tmp_desc, 1) != 0)
252	perror_with_name ("Can't listen on socket");
253
254      remote_desc = accept (tmp_desc, (struct sockaddr *) &sockaddr,
255			    &sockaddrsize);
256
257      if (remote_desc == -1)
258	perror_with_name ("Accept failed");
259
260      /* Enable TCP keep alive process. */
261      tmp = 1;
262      setsockopt (tmp_desc, SOL_SOCKET, SO_KEEPALIVE,
263		  (char *) &tmp, sizeof (tmp));
264
265      /* Tell TCP not to delay small packets.  This greatly speeds up
266	 interactive response. */
267      tmp = 1;
268      setsockopt (remote_desc, IPPROTO_TCP, TCP_NODELAY,
269		  (char *) &tmp, sizeof (tmp));
270
271      if (getnameinfo ((struct sockaddr *) &sockaddr, sockaddrsize,
272		       orig_host, sizeof (orig_host),
273		       orig_port, sizeof (orig_port),
274		       NI_NUMERICHOST | NI_NUMERICSERV) == 0)
275	{
276	  fprintf (stderr, "Remote debugging from host %s, port %s\n",
277		   orig_host, orig_port);
278	  fflush (stderr);
279	}
280
281#ifndef USE_WIN32API
282      close (tmp_desc);		/* No longer need this */
283
284      signal (SIGPIPE, SIG_IGN);	/* If we don't do this, then
285					   gdbreplay simply exits when
286					   the remote side dies.  */
287#else
288      closesocket (tmp_desc);	/* No longer need this */
289#endif
290    }
291
292#if defined(F_SETFL) && defined (FASYNC)
293  fcntl (remote_desc, F_SETFL, FASYNC);
294#endif
295
296  fprintf (stderr, "Replay logfile using %s\n", name);
297  fflush (stderr);
298}
299
300static int
301logchar (FILE *fp)
302{
303  int ch;
304  int ch2;
305
306  ch = fgetc (fp);
307  if (ch != '\r')
308    {
309      fputc (ch, stdout);
310      fflush (stdout);
311    }
312  switch (ch)
313    {
314      /* Treat \r\n as a newline.  */
315    case '\r':
316      ch = fgetc (fp);
317      if (ch == '\n')
318	ch = EOL;
319      else
320	{
321	  ungetc (ch, fp);
322	  ch = '\r';
323	}
324      fputc (ch == EOL ? '\n' : '\r', stdout);
325      fflush (stdout);
326      break;
327    case '\n':
328      ch = EOL;
329      break;
330    case '\\':
331      ch = fgetc (fp);
332      fputc (ch, stdout);
333      fflush (stdout);
334      switch (ch)
335	{
336	case '\\':
337	  break;
338	case 'b':
339	  ch = '\b';
340	  break;
341	case 'f':
342	  ch = '\f';
343	  break;
344	case 'n':
345	  ch = '\n';
346	  break;
347	case 'r':
348	  ch = '\r';
349	  break;
350	case 't':
351	  ch = '\t';
352	  break;
353	case 'v':
354	  ch = '\v';
355	  break;
356	case 'x':
357	  ch2 = fgetc (fp);
358	  fputc (ch2, stdout);
359	  fflush (stdout);
360	  ch = fromhex (ch2) << 4;
361	  ch2 = fgetc (fp);
362	  fputc (ch2, stdout);
363	  fflush (stdout);
364	  ch |= fromhex (ch2);
365	  break;
366	default:
367	  /* Treat any other char as just itself */
368	  break;
369	}
370    default:
371      break;
372    }
373  return (ch);
374}
375
376static int
377gdbchar (int desc)
378{
379  unsigned char fromgdb;
380
381  if (read (desc, &fromgdb, 1) != 1)
382    return -1;
383  else
384    return fromgdb;
385}
386
387/* Accept input from gdb and match with chars from fp (after skipping one
388   blank) up until a \n is read from fp (which is not matched) */
389
390static void
391expect (FILE *fp)
392{
393  int fromlog;
394  int fromgdb;
395
396  if ((fromlog = logchar (fp)) != ' ')
397    {
398      sync_error (fp, "Sync error during gdb read of leading blank", ' ',
399		  fromlog);
400    }
401  do
402    {
403      fromlog = logchar (fp);
404      if (fromlog == EOL)
405	break;
406      fromgdb = gdbchar (remote_desc);
407      if (fromgdb < 0)
408	remote_error ("Error during read from gdb");
409    }
410  while (fromlog == fromgdb);
411
412  if (fromlog != EOL)
413    {
414      sync_error (fp, "Sync error during read of gdb packet from log", fromlog,
415		  fromgdb);
416    }
417}
418
419/* Play data back to gdb from fp (after skipping leading blank) up until a
420   \n is read from fp (which is discarded and not sent to gdb). */
421
422static void
423play (FILE *fp)
424{
425  int fromlog;
426  char ch;
427
428  if ((fromlog = logchar (fp)) != ' ')
429    {
430      sync_error (fp, "Sync error skipping blank during write to gdb", ' ',
431		  fromlog);
432    }
433  while ((fromlog = logchar (fp)) != EOL)
434    {
435      ch = fromlog;
436      if (write (remote_desc, &ch, 1) != 1)
437	remote_error ("Error during write to gdb");
438    }
439}
440
441static void
442gdbreplay_version (void)
443{
444  printf ("GNU gdbreplay %s%s\n"
445	  "Copyright (C) 2020 Free Software Foundation, Inc.\n"
446	  "gdbreplay is free software, covered by "
447	  "the GNU General Public License.\n"
448	  "This gdbreplay was configured as \"%s\"\n",
449	  PKGVERSION, version, host_name);
450}
451
452static void
453gdbreplay_usage (FILE *stream)
454{
455  fprintf (stream, "Usage:\tgdbreplay LOGFILE HOST:PORT\n");
456  if (REPORT_BUGS_TO[0] && stream == stdout)
457    fprintf (stream, "Report bugs to \"%s\".\n", REPORT_BUGS_TO);
458}
459
460/* Main function.  This is called by the real "main" function,
461   wrapped in a TRY_CATCH that handles any uncaught exceptions.  */
462
463static void ATTRIBUTE_NORETURN
464captured_main (int argc, char *argv[])
465{
466  FILE *fp;
467  int ch;
468
469  if (argc >= 2 && strcmp (argv[1], "--version") == 0)
470    {
471      gdbreplay_version ();
472      exit (0);
473    }
474  if (argc >= 2 && strcmp (argv[1], "--help") == 0)
475    {
476      gdbreplay_usage (stdout);
477      exit (0);
478    }
479
480  if (argc < 3)
481    {
482      gdbreplay_usage (stderr);
483      exit (1);
484    }
485  fp = fopen (argv[1], "r");
486  if (fp == NULL)
487    {
488      perror_with_name (argv[1]);
489    }
490  remote_open (argv[2]);
491  while ((ch = logchar (fp)) != EOF)
492    {
493      switch (ch)
494	{
495	case 'w':
496	  /* data sent from gdb to gdbreplay, accept and match it */
497	  expect (fp);
498	  break;
499	case 'r':
500	  /* data sent from gdbreplay to gdb, play it */
501	  play (fp);
502	  break;
503	case 'c':
504	  /* Command executed by gdb */
505	  while ((ch = logchar (fp)) != EOL);
506	  break;
507	}
508    }
509  remote_close ();
510  exit (0);
511}
512
513int
514main (int argc, char *argv[])
515{
516  try
517    {
518      captured_main (argc, argv);
519    }
520  catch (const gdb_exception &exception)
521    {
522      if (exception.reason == RETURN_ERROR)
523	{
524	  fflush (stdout);
525	  fprintf (stderr, "%s\n", exception.what ());
526	}
527
528      exit (1);
529    }
530
531  gdb_assert_not_reached ("captured_main should never return");
532}
533