gdb/gdbserver/gdbreplay.c

   1 /* Replay a remote debug session logfile for GDB.
   2    Copyright (C) 1996-2018 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 "common-defs.h"
  21 #include "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 <winsock2.h>
  49 #endif
  50
  51 #ifndef HAVE_SOCKLEN_T
  52 typedef int socklen_t;
  53 #endif
  54
  55 /* Sort of a hack... */
  56 #define EOL (EOF - 1)
  57
  58 static int remote_desc;
  59
  60 #ifdef __MINGW32CE__
  61
  62 #ifndef COUNTOF
  63 #define COUNTOF(STR) (sizeof (STR) / sizeof ((STR)[0]))
  64 #endif
  65
  66 #define errno (GetLastError ())
  67
  68 char *
  69 strerror (DWORD error)
  70 {
  71   static char buf[1024];
  72   WCHAR *msgbuf;
  73   DWORD lasterr = GetLastError ();
  74   DWORD chars = FormatMessageW (FORMAT_MESSAGE_FROM_SYSTEM
  75                                 | FORMAT_MESSAGE_ALLOCATE_BUFFER,
  76                                 NULL,
  77                                 error,
  78                                 0, /* Default language */
  79                                 (LPVOID)&msgbuf,
  80                                 0,
  81                                 NULL);
  82   if (chars != 0)
  83     {
  84       /* If there is an \r\n appended, zap it.  */
  85       if (chars >= 2
  86           && msgbuf[chars - 2] == '\r'
  87           && msgbuf[chars - 1] == '\n')
  88         {
  89           chars -= 2;
  90           msgbuf[chars] = 0;
  91         }
  92
  93       if (chars > ((COUNTOF (buf)) - 1))
  94         {
  95           chars = COUNTOF (buf) - 1;
  96           msgbuf [chars] = 0;
  97         }
  98
  99       wcstombs (buf, msgbuf, chars + 1);
 100       LocalFree (msgbuf);
 101     }
 102   else
 103     sprintf (buf, "unknown win32 error (%ld)", error);
 104
 105   SetLastError (lasterr);
 106   return buf;
 107 }
 108
 109 #endif /* __MINGW32CE__ */
 110
 111 static void
 112 sync_error (FILE *fp, const char *desc, int expect, int got)
 113 {
 114   fprintf (stderr, "\n%s\n", desc);
 115   fprintf (stderr, "At logfile offset %ld, expected '0x%x' got '0x%x'\n",
 116            ftell (fp), expect, got);
 117   fflush (stderr);
 118   exit (1);
 119 }
 120
 121 static void
 122 remote_error (const char *desc)
 123 {
 124   fprintf (stderr, "\n%s\n", desc);
 125   fflush (stderr);
 126   exit (1);
 127 }
 128
 129 static void
 130 remote_close (void)
 131 {
 132 #ifdef USE_WIN32API
 133   closesocket (remote_desc);
 134 #else
 135   close (remote_desc);
 136 #endif
 137 }
 138
 139 /* Open a connection to a remote debugger.
 140    NAME is the filename used for communication.  */
 141
 142 static void
 143 remote_open (char *name)
 144 {
 145   if (!strchr (name, ':'))
 146     {
 147       fprintf (stderr, "%s: Must specify tcp connection as host:addr\n", name);
 148       fflush (stderr);
 149       exit (1);
 150     }
 151   else
 152     {
 153 #ifdef USE_WIN32API
 154       static int winsock_initialized;
 155 #endif
 156       char *port_str;
 157       int port;
 158       struct sockaddr_in sockaddr;
 159       socklen_t tmp;
 160       int tmp_desc;
 161
 162       port_str = strchr (name, ':');
 163
 164       port = atoi (port_str + 1);
 165
 166 #ifdef USE_WIN32API
 167       if (!winsock_initialized)
 168         {
 169           WSADATA wsad;
 170
 171           WSAStartup (MAKEWORD (1, 0), &wsad);
 172           winsock_initialized = 1;
 173         }
 174 #endif
 175
 176       tmp_desc = socket (PF_INET, SOCK_STREAM, 0);
 177       if (tmp_desc == -1)
 178         perror_with_name ("Can't open socket");
 179
 180       /* Allow rapid reuse of this port. */
 181       tmp = 1;
 182       setsockopt (tmp_desc, SOL_SOCKET, SO_REUSEADDR, (char *) &tmp,
 183                   sizeof (tmp));
 184
 185       sockaddr.sin_family = PF_INET;
 186       sockaddr.sin_port = htons (port);
 187       sockaddr.sin_addr.s_addr = INADDR_ANY;
 188
 189       if (bind (tmp_desc, (struct sockaddr *) &sockaddr, sizeof (sockaddr))
 190           || listen (tmp_desc, 1))
 191         perror_with_name ("Can't bind address");
 192
 193       tmp = sizeof (sockaddr);
 194       remote_desc = accept (tmp_desc, (struct sockaddr *) &sockaddr, &tmp);
 195       if (remote_desc == -1)
 196         perror_with_name ("Accept failed");
 197
 198       /* Enable TCP keep alive process. */
 199       tmp = 1;
 200       setsockopt (tmp_desc, SOL_SOCKET, SO_KEEPALIVE,
 201                   (char *) &tmp, sizeof (tmp));
 202
 203       /* Tell TCP not to delay small packets.  This greatly speeds up
 204          interactive response. */
 205       tmp = 1;
 206       setsockopt (remote_desc, IPPROTO_TCP, TCP_NODELAY,
 207                   (char *) &tmp, sizeof (tmp));
 208
 209 #ifndef USE_WIN32API
 210       close (tmp_desc);         /* No longer need this */
 211
 212       signal (SIGPIPE, SIG_IGN);        /* If we don't do this, then
 213                                            gdbreplay simply exits when
 214                                            the remote side dies.  */
 215 #else
 216       closesocket (tmp_desc);   /* No longer need this */
 217 #endif
 218     }
 219
 220 #if defined(F_SETFL) && defined (FASYNC)
 221   fcntl (remote_desc, F_SETFL, FASYNC);
 222 #endif
 223
 224   fprintf (stderr, "Replay logfile using %s\n", name);
 225   fflush (stderr);
 226 }
 227
 228 static int
 229 fromhex (int ch)
 230 {
 231   if (ch >= '0' && ch <= '9')
 232     {
 233       return (ch - '0');
 234     }
 235   if (ch >= 'A' && ch <= 'F')
 236     {
 237       return (ch - 'A' + 10);
 238     }
 239   if (ch >= 'a' && ch <= 'f')
 240     {
 241       return (ch - 'a' + 10);
 242     }
 243   fprintf (stderr, "\nInvalid hex digit '%c'\n", ch);
 244   fflush (stderr);
 245   exit (1);
 246 }
 247
 248 static int
 249 logchar (FILE *fp)
 250 {
 251   int ch;
 252   int ch2;
 253
 254   ch = fgetc (fp);
 255   fputc (ch, stdout);
 256   fflush (stdout);
 257   switch (ch)
 258     {
 259     case '\n':
 260       ch = EOL;
 261       break;
 262     case '\\':
 263       ch = fgetc (fp);
 264       fputc (ch, stdout);
 265       fflush (stdout);
 266       switch (ch)
 267         {
 268         case '\\':
 269           break;
 270         case 'b':
 271           ch = '\b';
 272           break;
 273         case 'f':
 274           ch = '\f';
 275           break;
 276         case 'n':
 277           ch = '\n';
 278           break;
 279         case 'r':
 280           ch = '\r';
 281           break;
 282         case 't':
 283           ch = '\t';
 284           break;
 285         case 'v':
 286           ch = '\v';
 287           break;
 288         case 'x':
 289           ch2 = fgetc (fp);
 290           fputc (ch2, stdout);
 291           fflush (stdout);
 292           ch = fromhex (ch2) << 4;
 293           ch2 = fgetc (fp);
 294           fputc (ch2, stdout);
 295           fflush (stdout);
 296           ch |= fromhex (ch2);
 297           break;
 298         default:
 299           /* Treat any other char as just itself */
 300           break;
 301         }
 302     default:
 303       break;
 304     }
 305   return (ch);
 306 }
 307
 308 static int
 309 gdbchar (int desc)
 310 {
 311   unsigned char fromgdb;
 312
 313   if (read (desc, &fromgdb, 1) != 1)
 314     return -1;
 315   else
 316     return fromgdb;
 317 }
 318
 319 /* Accept input from gdb and match with chars from fp (after skipping one
 320    blank) up until a \n is read from fp (which is not matched) */
 321
 322 static void
 323 expect (FILE *fp)
 324 {
 325   int fromlog;
 326   int fromgdb;
 327
 328   if ((fromlog = logchar (fp)) != ' ')
 329     {
 330       sync_error (fp, "Sync error during gdb read of leading blank", ' ',
 331                   fromlog);
 332     }
 333   do
 334     {
 335       fromlog = logchar (fp);
 336       if (fromlog == EOL)
 337         break;
 338       fromgdb = gdbchar (remote_desc);
 339       if (fromgdb < 0)
 340         remote_error ("Error during read from gdb");
 341     }
 342   while (fromlog == fromgdb);
 343
 344   if (fromlog != EOL)
 345     {
 346       sync_error (fp, "Sync error during read of gdb packet from log", fromlog,
 347                   fromgdb);
 348     }
 349 }
 350
 351 /* Play data back to gdb from fp (after skipping leading blank) up until a
 352    \n is read from fp (which is discarded and not sent to gdb). */
 353
 354 static void
 355 play (FILE *fp)
 356 {
 357   int fromlog;
 358   char ch;
 359
 360   if ((fromlog = logchar (fp)) != ' ')
 361     {
 362       sync_error (fp, "Sync error skipping blank during write to gdb", ' ',
 363                   fromlog);
 364     }
 365   while ((fromlog = logchar (fp)) != EOL)
 366     {
 367       ch = fromlog;
 368       if (write (remote_desc, &ch, 1) != 1)
 369         remote_error ("Error during write to gdb");
 370     }
 371 }
 372
 373 static void
 374 gdbreplay_version (void)
 375 {
 376   printf ("GNU gdbreplay %s%s\n"
 377           "Copyright (C) 2018 Free Software Foundation, Inc.\n"
 378           "gdbreplay is free software, covered by "
 379           "the GNU General Public License.\n"
 380           "This gdbreplay was configured as \"%s\"\n",
 381           PKGVERSION, version, host_name);
 382 }
 383
 384 static void
 385 gdbreplay_usage (FILE *stream)
 386 {
 387   fprintf (stream, "Usage:\tgdbreplay <logfile> <host:port>\n");
 388   if (REPORT_BUGS_TO[0] && stream == stdout)
 389     fprintf (stream, "Report bugs to \"%s\".\n", REPORT_BUGS_TO);
 390 }
 391
 392 /* Main function.  This is called by the real "main" function,
 393    wrapped in a TRY_CATCH that handles any uncaught exceptions.  */
 394
 395 static void ATTRIBUTE_NORETURN
 396 captured_main (int argc, char *argv[])
 397 {
 398   FILE *fp;
 399   int ch;
 400
 401   if (argc >= 2 && strcmp (argv[1], "--version") == 0)
 402     {
 403       gdbreplay_version ();
 404       exit (0);
 405     }
 406   if (argc >= 2 && strcmp (argv[1], "--help") == 0)
 407     {
 408       gdbreplay_usage (stdout);
 409       exit (0);
 410     }
 411
 412   if (argc < 3)
 413     {
 414       gdbreplay_usage (stderr);
 415       exit (1);
 416     }
 417   fp = fopen (argv[1], "r");
 418   if (fp == NULL)
 419     {
 420       perror_with_name (argv[1]);
 421     }
 422   remote_open (argv[2]);
 423   while ((ch = logchar (fp)) != EOF)
 424     {
 425       switch (ch)
 426         {
 427         case 'w':
 428           /* data sent from gdb to gdbreplay, accept and match it */
 429           expect (fp);
 430           break;
 431         case 'r':
 432           /* data sent from gdbreplay to gdb, play it */
 433           play (fp);
 434           break;
 435         case 'c':
 436           /* Command executed by gdb */
 437           while ((ch = logchar (fp)) != EOL);
 438           break;
 439         }
 440     }
 441   remote_close ();
 442   exit (0);
 443 }
 444
 445 int
 446 main (int argc, char *argv[])
 447 {
 448   TRY
 449     {
 450       captured_main (argc, argv);
 451     }
 452   CATCH (exception, RETURN_MASK_ALL)
 453     {
 454       if (exception.reason == RETURN_ERROR)
 455         {
 456           fflush (stdout);
 457           fprintf (stderr, "%s\n", exception.message);
 458         }
 459
 460       exit (1);
 461     }
 462   END_CATCH
 463
 464   gdb_assert_not_reached ("captured_main should never return");
 465 }