gdb/gdbserver/gdbreplay.c

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