gdbserver/gdbreplay.cc

   1 /* Replay a remote debug session logfile for GDB.
   2    Copyright (C) 1996-2023 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 static void
  73 sync_error (FILE *fp, const char *desc, int expect, int got)
  74 {
  75   fprintf (stderr, "\n%s\n", desc);
  76   fprintf (stderr, "At logfile offset %ld, expected '0x%x' got '0x%x'\n",
  77            ftell (fp), expect, got);
  78   fflush (stderr);
  79   exit (1);
  80 }
  81
  82 static void
  83 remote_error (const char *desc)
  84 {
  85   fprintf (stderr, "\n%s\n", desc);
  86   fflush (stderr);
  87   exit (1);
  88 }
  89
  90 static void
  91 remote_close (void)
  92 {
  93 #ifdef USE_WIN32API
  94   gdb_assert (remote_desc_in == remote_desc_out);
  95   closesocket (remote_desc_in);
  96 #else
  97   close (remote_desc_in);
  98   if (remote_desc_in != remote_desc_out)
  99     close (remote_desc_out);
 100 #endif
 101 }
 102
 103 /* Open a connection to a remote debugger.
 104    NAME is the filename used for communication.  */
 105
 106 static void
 107 remote_open (const char *name)
 108 {
 109 #ifndef USE_WIN32API
 110   if (strcmp (name, "-") == 0)
 111     {
 112       remote_desc_in = 0;
 113       remote_desc_out = 1;
 114       return;
 115     }
 116 #endif
 117
 118   const char *last_colon = strrchr (name, ':');
 119
 120   if (last_colon == NULL)
 121     {
 122       fprintf (stderr, "%s: Must specify tcp connection as host:addr\n", name);
 123       fflush (stderr);
 124       exit (1);
 125     }
 126
 127 #ifdef USE_WIN32API
 128   static int winsock_initialized;
 129 #endif
 130   int tmp;
 131   int tmp_desc;
 132   struct addrinfo hint;
 133   struct addrinfo *ainfo;
 134
 135   memset (&hint, 0, sizeof (hint));
 136   /* Assume no prefix will be passed, therefore we should use
 137      AF_UNSPEC.  */
 138   hint.ai_family = AF_UNSPEC;
 139   hint.ai_socktype = SOCK_STREAM;
 140   hint.ai_protocol = IPPROTO_TCP;
 141
 142   parsed_connection_spec parsed = parse_connection_spec (name, &hint);
 143
 144   if (parsed.port_str.empty ())
 145     error (_("Missing port on hostname '%s'"), name);
 146
 147 #ifdef USE_WIN32API
 148   if (!winsock_initialized)
 149     {
 150       WSADATA wsad;
 151
 152       WSAStartup (MAKEWORD (1, 0), &wsad);
 153       winsock_initialized = 1;
 154     }
 155 #endif
 156
 157   int r = getaddrinfo (parsed.host_str.c_str (), parsed.port_str.c_str (),
 158                        &hint, &ainfo);
 159
 160   if (r != 0)
 161     {
 162       fprintf (stderr, "%s:%s: cannot resolve name: %s\n",
 163                parsed.host_str.c_str (), parsed.port_str.c_str (),
 164                gai_strerror (r));
 165       fflush (stderr);
 166       exit (1);
 167     }
 168
 169   scoped_free_addrinfo free_ainfo (ainfo);
 170
 171   struct addrinfo *p;
 172
 173   for (p = ainfo; p != NULL; p = p->ai_next)
 174     {
 175       tmp_desc = socket (p->ai_family, p->ai_socktype, p->ai_protocol);
 176
 177       if (tmp_desc >= 0)
 178         break;
 179     }
 180
 181   if (p == NULL)
 182     perror_with_name ("Cannot open socket");
 183
 184   /* Allow rapid reuse of this port. */
 185   tmp = 1;
 186   setsockopt (tmp_desc, SOL_SOCKET, SO_REUSEADDR, (char *) &tmp,
 187               sizeof (tmp));
 188
 189   switch (p->ai_family)
 190     {
 191     case AF_INET:
 192       ((struct sockaddr_in *) p->ai_addr)->sin_addr.s_addr = INADDR_ANY;
 193       break;
 194     case AF_INET6:
 195       ((struct sockaddr_in6 *) p->ai_addr)->sin6_addr = in6addr_any;
 196       break;
 197     default:
 198       fprintf (stderr, "Invalid 'ai_family' %d\n", p->ai_family);
 199       exit (1);
 200     }
 201
 202   if (bind (tmp_desc, p->ai_addr, p->ai_addrlen) != 0)
 203     perror_with_name ("Can't bind address");
 204
 205   if (p->ai_socktype == SOCK_DGRAM)
 206     remote_desc_in = tmp_desc;
 207   else
 208     {
 209       struct sockaddr_storage sockaddr;
 210       socklen_t sockaddrsize = sizeof (sockaddr);
 211       char orig_host[GDB_NI_MAX_ADDR], orig_port[GDB_NI_MAX_PORT];
 212
 213       if (listen (tmp_desc, 1) != 0)
 214         perror_with_name ("Can't listen on socket");
 215
 216       remote_desc_in = accept (tmp_desc, (struct sockaddr *) &sockaddr,
 217                                &sockaddrsize);
 218
 219       if (remote_desc_in == -1)
 220         perror_with_name ("Accept failed");
 221
 222       /* Enable TCP keep alive process. */
 223       tmp = 1;
 224       setsockopt (tmp_desc, SOL_SOCKET, SO_KEEPALIVE,
 225                   (char *) &tmp, sizeof (tmp));
 226
 227       /* Tell TCP not to delay small packets.  This greatly speeds up
 228          interactive response. */
 229       tmp = 1;
 230       setsockopt (remote_desc_in, IPPROTO_TCP, TCP_NODELAY,
 231                   (char *) &tmp, sizeof (tmp));
 232
 233       if (getnameinfo ((struct sockaddr *) &sockaddr, sockaddrsize,
 234                        orig_host, sizeof (orig_host),
 235                        orig_port, sizeof (orig_port),
 236                        NI_NUMERICHOST | NI_NUMERICSERV) == 0)
 237         {
 238           fprintf (stderr, "Remote debugging from host %s, port %s\n",
 239                    orig_host, orig_port);
 240           fflush (stderr);
 241         }
 242
 243 #ifndef USE_WIN32API
 244       close (tmp_desc);         /* No longer need this */
 245
 246       signal (SIGPIPE, SIG_IGN);        /* If we don't do this, then
 247                                            gdbreplay simply exits when
 248                                            the remote side dies.  */
 249 #else
 250       closesocket (tmp_desc);   /* No longer need this */
 251 #endif
 252     }
 253
 254 #if defined(F_SETFL) && defined (FASYNC)
 255   fcntl (remote_desc_in, F_SETFL, FASYNC);
 256 #endif
 257   remote_desc_out = remote_desc_in;
 258
 259   fprintf (stderr, "Replay logfile using %s\n", name);
 260   fflush (stderr);
 261 }
 262
 263 static int
 264 logchar (FILE *fp)
 265 {
 266   int ch;
 267   int ch2;
 268
 269   ch = fgetc (fp);
 270   if (ch != '\r')
 271     {
 272       fputc (ch, stderr);
 273       fflush (stderr);
 274     }
 275   switch (ch)
 276     {
 277       /* Treat \r\n as a newline.  */
 278     case '\r':
 279       ch = fgetc (fp);
 280       if (ch == '\n')
 281         ch = EOL;
 282       else
 283         {
 284           ungetc (ch, fp);
 285           ch = '\r';
 286         }
 287       fputc (ch == EOL ? '\n' : '\r', stderr);
 288       fflush (stderr);
 289       break;
 290     case '\n':
 291       ch = EOL;
 292       break;
 293     case '\\':
 294       ch = fgetc (fp);
 295       fputc (ch, stderr);
 296       fflush (stderr);
 297       switch (ch)
 298         {
 299         case '\\':
 300           break;
 301         case 'b':
 302           ch = '\b';
 303           break;
 304         case 'f':
 305           ch = '\f';
 306           break;
 307         case 'n':
 308           ch = '\n';
 309           break;
 310         case 'r':
 311           ch = '\r';
 312           break;
 313         case 't':
 314           ch = '\t';
 315           break;
 316         case 'v':
 317           ch = '\v';
 318           break;
 319         case 'x':
 320           ch2 = fgetc (fp);
 321           fputc (ch2, stderr);
 322           fflush (stderr);
 323           ch = fromhex (ch2) << 4;
 324           ch2 = fgetc (fp);
 325           fputc (ch2, stderr);
 326           fflush (stderr);
 327           ch |= fromhex (ch2);
 328           break;
 329         default:
 330           /* Treat any other char as just itself */
 331           break;
 332         }
 333     default:
 334       break;
 335     }
 336   return (ch);
 337 }
 338
 339 static int
 340 gdbchar (int desc)
 341 {
 342   unsigned char fromgdb;
 343
 344   if (read (desc, &fromgdb, 1) != 1)
 345     return -1;
 346   else
 347     return fromgdb;
 348 }
 349
 350 /* Accept input from gdb and match with chars from fp (after skipping one
 351    blank) up until a \n is read from fp (which is not matched) */
 352
 353 static void
 354 expect (FILE *fp)
 355 {
 356   int fromlog;
 357   int fromgdb;
 358
 359   if ((fromlog = logchar (fp)) != ' ')
 360     {
 361       sync_error (fp, "Sync error during gdb read of leading blank", ' ',
 362                   fromlog);
 363     }
 364   do
 365     {
 366       fromlog = logchar (fp);
 367       if (fromlog == EOL)
 368         break;
 369       fromgdb = gdbchar (remote_desc_in);
 370       if (fromgdb < 0)
 371         remote_error ("Error during read from gdb");
 372     }
 373   while (fromlog == fromgdb);
 374
 375   if (fromlog != EOL)
 376     {
 377       sync_error (fp, "Sync error during read of gdb packet from log", fromlog,
 378                   fromgdb);
 379     }
 380 }
 381
 382 /* Play data back to gdb from fp (after skipping leading blank) up until a
 383    \n is read from fp (which is discarded and not sent to gdb). */
 384
 385 static void
 386 play (FILE *fp)
 387 {
 388   int fromlog;
 389   char ch;
 390
 391   if ((fromlog = logchar (fp)) != ' ')
 392     {
 393       sync_error (fp, "Sync error skipping blank during write to gdb", ' ',
 394                   fromlog);
 395     }
 396   while ((fromlog = logchar (fp)) != EOL)
 397     {
 398       ch = fromlog;
 399       if (write (remote_desc_out, &ch, 1) != 1)
 400         remote_error ("Error during write to gdb");
 401     }
 402 }
 403
 404 static void
 405 gdbreplay_version (void)
 406 {
 407   printf ("GNU gdbreplay %s%s\n"
 408           "Copyright (C) 2023 Free Software Foundation, Inc.\n"
 409           "gdbreplay is free software, covered by "
 410           "the GNU General Public License.\n"
 411           "This gdbreplay was configured as \"%s\"\n",
 412           PKGVERSION, version, host_name);
 413 }
 414
 415 static void
 416 gdbreplay_usage (FILE *stream)
 417 {
 418   fprintf (stream, "Usage:\tgdbreplay LOGFILE HOST:PORT\n");
 419   if (REPORT_BUGS_TO[0] && stream == stdout)
 420     fprintf (stream, "Report bugs to \"%s\".\n", REPORT_BUGS_TO);
 421 }
 422
 423 /* Main function.  This is called by the real "main" function,
 424    wrapped in a TRY_CATCH that handles any uncaught exceptions.  */
 425
 426 static void ATTRIBUTE_NORETURN
 427 captured_main (int argc, char *argv[])
 428 {
 429   FILE *fp;
 430   int ch;
 431
 432   if (argc >= 2 && strcmp (argv[1], "--version") == 0)
 433     {
 434       gdbreplay_version ();
 435       exit (0);
 436     }
 437   if (argc >= 2 && strcmp (argv[1], "--help") == 0)
 438     {
 439       gdbreplay_usage (stdout);
 440       exit (0);
 441     }
 442
 443   if (argc < 3)
 444     {
 445       gdbreplay_usage (stderr);
 446       exit (1);
 447     }
 448   fp = fopen (argv[1], "r");
 449   if (fp == NULL)
 450     {
 451       perror_with_name (argv[1]);
 452     }
 453   remote_open (argv[2]);
 454   while ((ch = logchar (fp)) != EOF)
 455     {
 456       switch (ch)
 457         {
 458         case 'w':
 459           /* data sent from gdb to gdbreplay, accept and match it */
 460           expect (fp);
 461           break;
 462         case 'r':
 463           /* data sent from gdbreplay to gdb, play it */
 464           play (fp);
 465           break;
 466         case 'c':
 467           /* Command executed by gdb */
 468           while ((ch = logchar (fp)) != EOL);
 469           break;
 470         }
 471     }
 472   remote_close ();
 473   exit (0);
 474 }
 475
 476 int
 477 main (int argc, char *argv[])
 478 {
 479   try
 480     {
 481       captured_main (argc, argv);
 482     }
 483   catch (const gdb_exception &exception)
 484     {
 485       if (exception.reason == RETURN_ERROR)
 486         {
 487           fflush (stdout);
 488           fprintf (stderr, "%s\n", exception.what ());
 489         }
 490
 491       exit (1);
 492     }
 493
 494   gdb_assert_not_reached ("captured_main should never return");
 495 }