gdbserver/gdbreplay.cc

   1 /* Replay a remote debug session logfile for GDB.
   2    Copyright (C) 1996-2021 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
  63 typedef int socklen_t;
  64 #endif
  65
  66 /* Sort of a hack... */
  67 #define EOL (EOF - 1)
  68
  69 static int remote_desc_in;
  70 static int remote_desc_out;
  71
  72 #ifdef __MINGW32CE__
  73
  74 #ifndef COUNTOF
  75 #define COUNTOF(STR) (sizeof (STR) / sizeof ((STR)[0]))
  76 #endif
  77
  78 #define errno (GetLastError ())
  79
  80 char *
  81 strerror (DWORD error)
  82 {
  83   static char buf[1024];
  84   WCHAR *msgbuf;
  85   DWORD lasterr = GetLastError ();
  86   DWORD chars = FormatMessageW (FORMAT_MESSAGE_FROM_SYSTEM
  87                                 | FORMAT_MESSAGE_ALLOCATE_BUFFER,
  88                                 NULL,
  89                                 error,
  90                                 0, /* Default language */
  91                                 (LPVOID)&msgbuf,
  92                                 0,
  93                                 NULL);
  94   if (chars != 0)
  95     {
  96       /* If there is an \r\n appended, zap it.  */
  97       if (chars >= 2
  98           && msgbuf[chars - 2] == '\r'
  99           && msgbuf[chars - 1] == '\n')
 100         {
 101           chars -= 2;
 102           msgbuf[chars] = 0;
 103         }
 104
 105       if (chars > ((COUNTOF (buf)) - 1))
 106         {
 107           chars = COUNTOF (buf) - 1;
 108           msgbuf [chars] = 0;
 109         }
 110
 111       wcstombs (buf, msgbuf, chars + 1);
 112       LocalFree (msgbuf);
 113     }
 114   else
 115     sprintf (buf, "unknown win32 error (%ld)", error);
 116
 117   SetLastError (lasterr);
 118   return buf;
 119 }
 120
 121 #endif /* __MINGW32CE__ */
 122
 123 static void
 124 sync_error (FILE *fp, const char *desc, int expect, int got)
 125 {
 126   fprintf (stderr, "\n%s\n", desc);
 127   fprintf (stderr, "At logfile offset %ld, expected '0x%x' got '0x%x'\n",
 128            ftell (fp), expect, got);
 129   fflush (stderr);
 130   exit (1);
 131 }
 132
 133 static void
 134 remote_error (const char *desc)
 135 {
 136   fprintf (stderr, "\n%s\n", desc);
 137   fflush (stderr);
 138   exit (1);
 139 }
 140
 141 static void
 142 remote_close (void)
 143 {
 144 #ifdef USE_WIN32API
 145   gdb_assert (remote_desc_in == remote_desc_out);
 146   closesocket (remote_desc_in);
 147 #else
 148   close (remote_desc_in);
 149   if (remote_desc_in != remote_desc_out)
 150     close (remote_desc_out);
 151 #endif
 152 }
 153
 154 /* Open a connection to a remote debugger.
 155    NAME is the filename used for communication.  */
 156
 157 static void
 158 remote_open (const char *name)
 159 {
 160 #ifndef USE_WIN32API
 161   if (strcmp (name, "-") == 0)
 162     {
 163       remote_desc_in = 0;
 164       remote_desc_out = 1;
 165       return;
 166     }
 167 #endif
 168
 169   const char *last_colon = strrchr (name, ':');
 170
 171   if (last_colon == NULL)
 172     {
 173       fprintf (stderr, "%s: Must specify tcp connection as host:addr\n", name);
 174       fflush (stderr);
 175       exit (1);
 176     }
 177
 178 #ifdef USE_WIN32API
 179   static int winsock_initialized;
 180 #endif
 181   int tmp;
 182   int tmp_desc;
 183   struct addrinfo hint;
 184   struct addrinfo *ainfo;
 185
 186   memset (&hint, 0, sizeof (hint));
 187   /* Assume no prefix will be passed, therefore we should use
 188      AF_UNSPEC.  */
 189   hint.ai_family = AF_UNSPEC;
 190   hint.ai_socktype = SOCK_STREAM;
 191   hint.ai_protocol = IPPROTO_TCP;
 192
 193   parsed_connection_spec parsed = parse_connection_spec (name, &hint);
 194
 195   if (parsed.port_str.empty ())
 196     error (_("Missing port on hostname '%s'"), name);
 197
 198 #ifdef USE_WIN32API
 199   if (!winsock_initialized)
 200     {
 201       WSADATA wsad;
 202
 203       WSAStartup (MAKEWORD (1, 0), &wsad);
 204       winsock_initialized = 1;
 205     }
 206 #endif
 207
 208   int r = getaddrinfo (parsed.host_str.c_str (), parsed.port_str.c_str (),
 209                        &hint, &ainfo);
 210
 211   if (r != 0)
 212     {
 213       fprintf (stderr, "%s:%s: cannot resolve name: %s\n",
 214                parsed.host_str.c_str (), parsed.port_str.c_str (),
 215                gai_strerror (r));
 216       fflush (stderr);
 217       exit (1);
 218     }
 219
 220   scoped_free_addrinfo free_ainfo (ainfo);
 221
 222   struct addrinfo *p;
 223
 224   for (p = ainfo; p != NULL; p = p->ai_next)
 225     {
 226       tmp_desc = socket (p->ai_family, p->ai_socktype, p->ai_protocol);
 227
 228       if (tmp_desc >= 0)
 229         break;
 230     }
 231
 232   if (p == NULL)
 233     perror_with_name ("Cannot open socket");
 234
 235   /* Allow rapid reuse of this port. */
 236   tmp = 1;
 237   setsockopt (tmp_desc, SOL_SOCKET, SO_REUSEADDR, (char *) &tmp,
 238               sizeof (tmp));
 239
 240   switch (p->ai_family)
 241     {
 242     case AF_INET:
 243       ((struct sockaddr_in *) p->ai_addr)->sin_addr.s_addr = INADDR_ANY;
 244       break;
 245     case AF_INET6:
 246       ((struct sockaddr_in6 *) p->ai_addr)->sin6_addr = in6addr_any;
 247       break;
 248     default:
 249       fprintf (stderr, "Invalid 'ai_family' %d\n", p->ai_family);
 250       exit (1);
 251     }
 252
 253   if (bind (tmp_desc, p->ai_addr, p->ai_addrlen) != 0)
 254     perror_with_name ("Can't bind address");
 255
 256   if (p->ai_socktype == SOCK_DGRAM)
 257     remote_desc_in = tmp_desc;
 258   else
 259     {
 260       struct sockaddr_storage sockaddr;
 261       socklen_t sockaddrsize = sizeof (sockaddr);
 262       char orig_host[GDB_NI_MAX_ADDR], orig_port[GDB_NI_MAX_PORT];
 263
 264       if (listen (tmp_desc, 1) != 0)
 265         perror_with_name ("Can't listen on socket");
 266
 267       remote_desc_in = accept (tmp_desc, (struct sockaddr *) &sockaddr,
 268                                &sockaddrsize);
 269
 270       if (remote_desc_in == -1)
 271         perror_with_name ("Accept failed");
 272
 273       /* Enable TCP keep alive process. */
 274       tmp = 1;
 275       setsockopt (tmp_desc, SOL_SOCKET, SO_KEEPALIVE,
 276                   (char *) &tmp, sizeof (tmp));
 277
 278       /* Tell TCP not to delay small packets.  This greatly speeds up
 279          interactive response. */
 280       tmp = 1;
 281       setsockopt (remote_desc_in, IPPROTO_TCP, TCP_NODELAY,
 282                   (char *) &tmp, sizeof (tmp));
 283
 284       if (getnameinfo ((struct sockaddr *) &sockaddr, sockaddrsize,
 285                        orig_host, sizeof (orig_host),
 286                        orig_port, sizeof (orig_port),
 287                        NI_NUMERICHOST | NI_NUMERICSERV) == 0)
 288         {
 289           fprintf (stderr, "Remote debugging from host %s, port %s\n",
 290                    orig_host, orig_port);
 291           fflush (stderr);
 292         }
 293
 294 #ifndef USE_WIN32API
 295       close (tmp_desc);         /* No longer need this */
 296
 297       signal (SIGPIPE, SIG_IGN);        /* If we don't do this, then
 298                                            gdbreplay simply exits when
 299                                            the remote side dies.  */
 300 #else
 301       closesocket (tmp_desc);   /* No longer need this */
 302 #endif
 303     }
 304
 305 #if defined(F_SETFL) && defined (FASYNC)
 306   fcntl (remote_desc_in, F_SETFL, FASYNC);
 307 #endif
 308   remote_desc_out = remote_desc_in;
 309
 310   fprintf (stderr, "Replay logfile using %s\n", name);
 311   fflush (stderr);
 312 }
 313
 314 static int
 315 logchar (FILE *fp)
 316 {
 317   int ch;
 318   int ch2;
 319
 320   ch = fgetc (fp);
 321   if (ch != '\r')
 322     {
 323       fputc (ch, stderr);
 324       fflush (stderr);
 325     }
 326   switch (ch)
 327     {
 328       /* Treat \r\n as a newline.  */
 329     case '\r':
 330       ch = fgetc (fp);
 331       if (ch == '\n')
 332         ch = EOL;
 333       else
 334         {
 335           ungetc (ch, fp);
 336           ch = '\r';
 337         }
 338       fputc (ch == EOL ? '\n' : '\r', stderr);
 339       fflush (stderr);
 340       break;
 341     case '\n':
 342       ch = EOL;
 343       break;
 344     case '\\':
 345       ch = fgetc (fp);
 346       fputc (ch, stderr);
 347       fflush (stderr);
 348       switch (ch)
 349         {
 350         case '\\':
 351           break;
 352         case 'b':
 353           ch = '\b';
 354           break;
 355         case 'f':
 356           ch = '\f';
 357           break;
 358         case 'n':
 359           ch = '\n';
 360           break;
 361         case 'r':
 362           ch = '\r';
 363           break;
 364         case 't':
 365           ch = '\t';
 366           break;
 367         case 'v':
 368           ch = '\v';
 369           break;
 370         case 'x':
 371           ch2 = fgetc (fp);
 372           fputc (ch2, stderr);
 373           fflush (stderr);
 374           ch = fromhex (ch2) << 4;
 375           ch2 = fgetc (fp);
 376           fputc (ch2, stderr);
 377           fflush (stderr);
 378           ch |= fromhex (ch2);
 379           break;
 380         default:
 381           /* Treat any other char as just itself */
 382           break;
 383         }
 384     default:
 385       break;
 386     }
 387   return (ch);
 388 }
 389
 390 static int
 391 gdbchar (int desc)
 392 {
 393   unsigned char fromgdb;
 394
 395   if (read (desc, &fromgdb, 1) != 1)
 396     return -1;
 397   else
 398     return fromgdb;
 399 }
 400
 401 /* Accept input from gdb and match with chars from fp (after skipping one
 402    blank) up until a \n is read from fp (which is not matched) */
 403
 404 static void
 405 expect (FILE *fp)
 406 {
 407   int fromlog;
 408   int fromgdb;
 409
 410   if ((fromlog = logchar (fp)) != ' ')
 411     {
 412       sync_error (fp, "Sync error during gdb read of leading blank", ' ',
 413                   fromlog);
 414     }
 415   do
 416     {
 417       fromlog = logchar (fp);
 418       if (fromlog == EOL)
 419         break;
 420       fromgdb = gdbchar (remote_desc_in);
 421       if (fromgdb < 0)
 422         remote_error ("Error during read from gdb");
 423     }
 424   while (fromlog == fromgdb);
 425
 426   if (fromlog != EOL)
 427     {
 428       sync_error (fp, "Sync error during read of gdb packet from log", fromlog,
 429                   fromgdb);
 430     }
 431 }
 432
 433 /* Play data back to gdb from fp (after skipping leading blank) up until a
 434    \n is read from fp (which is discarded and not sent to gdb). */
 435
 436 static void
 437 play (FILE *fp)
 438 {
 439   int fromlog;
 440   char ch;
 441
 442   if ((fromlog = logchar (fp)) != ' ')
 443     {
 444       sync_error (fp, "Sync error skipping blank during write to gdb", ' ',
 445                   fromlog);
 446     }
 447   while ((fromlog = logchar (fp)) != EOL)
 448     {
 449       ch = fromlog;
 450       if (write (remote_desc_out, &ch, 1) != 1)
 451         remote_error ("Error during write to gdb");
 452     }
 453 }
 454
 455 static void
 456 gdbreplay_version (void)
 457 {
 458   printf ("GNU gdbreplay %s%s\n"
 459           "Copyright (C) 2021 Free Software Foundation, Inc.\n"
 460           "gdbreplay is free software, covered by "
 461           "the GNU General Public License.\n"
 462           "This gdbreplay was configured as \"%s\"\n",
 463           PKGVERSION, version, host_name);
 464 }
 465
 466 static void
 467 gdbreplay_usage (FILE *stream)
 468 {
 469   fprintf (stream, "Usage:\tgdbreplay LOGFILE HOST:PORT\n");
 470   if (REPORT_BUGS_TO[0] && stream == stdout)
 471     fprintf (stream, "Report bugs to \"%s\".\n", REPORT_BUGS_TO);
 472 }
 473
 474 /* Main function.  This is called by the real "main" function,
 475    wrapped in a TRY_CATCH that handles any uncaught exceptions.  */
 476
 477 static void ATTRIBUTE_NORETURN
 478 captured_main (int argc, char *argv[])
 479 {
 480   FILE *fp;
 481   int ch;
 482
 483   if (argc >= 2 && strcmp (argv[1], "--version") == 0)
 484     {
 485       gdbreplay_version ();
 486       exit (0);
 487     }
 488   if (argc >= 2 && strcmp (argv[1], "--help") == 0)
 489     {
 490       gdbreplay_usage (stdout);
 491       exit (0);
 492     }
 493
 494   if (argc < 3)
 495     {
 496       gdbreplay_usage (stderr);
 497       exit (1);
 498     }
 499   fp = fopen (argv[1], "r");
 500   if (fp == NULL)
 501     {
 502       perror_with_name (argv[1]);
 503     }
 504   remote_open (argv[2]);
 505   while ((ch = logchar (fp)) != EOF)
 506     {
 507       switch (ch)
 508         {
 509         case 'w':
 510           /* data sent from gdb to gdbreplay, accept and match it */
 511           expect (fp);
 512           break;
 513         case 'r':
 514           /* data sent from gdbreplay to gdb, play it */
 515           play (fp);
 516           break;
 517         case 'c':
 518           /* Command executed by gdb */
 519           while ((ch = logchar (fp)) != EOL);
 520           break;
 521         }
 522     }
 523   remote_close ();
 524   exit (0);
 525 }
 526
 527 int
 528 main (int argc, char *argv[])
 529 {
 530   try
 531     {
 532       captured_main (argc, argv);
 533     }
 534   catch (const gdb_exception &exception)
 535     {
 536       if (exception.reason == RETURN_ERROR)
 537         {
 538           fflush (stdout);
 539           fprintf (stderr, "%s\n", exception.what ());
 540         }
 541
 542       exit (1);
 543     }
 544
 545   gdb_assert_not_reached ("captured_main should never return");
 546 }