gdbserver/gdbreplay.cc

   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
  63 typedef int socklen_t;
  64 #endif
  65
  66 /* Sort of a hack... */
  67 #define EOL (EOF - 1)
  68
  69 static 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
  79 char *
  80 strerror (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
 122 static void
 123 sync_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
 132 static void
 133 remote_error (const char *desc)
 134 {
 135   fprintf (stderr, "\n%s\n", desc);
 136   fflush (stderr);
 137   exit (1);
 138 }
 139
 140 static void
 141 remote_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
 153 static void
 154 remote_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
 300 static int
 301 logchar (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
 376 static int
 377 gdbchar (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
 390 static void
 391 expect (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
 422 static void
 423 play (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
 441 static void
 442 gdbreplay_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
 452 static void
 453 gdbreplay_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
 463 static void ATTRIBUTE_NORETURN
 464 captured_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
 513 int
 514 main (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 }