1 /* Main code for remote server for GDB. 2 Copyright (C) 1989, 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2002, 2003, 3 2004, 2005, 2006, 2011 4 Free Software Foundation, Inc. 5 6 This file is part of GDB. 7 It has been modified to integrate it in valgrind 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 2 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; if not, write to the Free Software 21 Foundation, Inc., 51 Franklin Street, Fifth Floor, 22 Boston, MA 02110-1301, USA. */ 23 24 #include "server.h" 25 #include "regdef.h" 26 #include "pub_core_options.h" 27 #include "pub_core_translate.h" 28 #include "pub_core_mallocfree.h" 29 #include "pub_core_initimg.h" 30 31 unsigned long cont_thread; 32 unsigned long general_thread; 33 unsigned long step_thread; 34 unsigned long thread_from_wait; 35 unsigned long old_thread_from_wait; 36 37 int pass_signals[TARGET_SIGNAL_LAST]; /* indexed by gdb signal nr */ 38 39 /* for a gdbserver integrated in valgrind, resuming the process consists 40 in returning the control to valgrind. 41 The guess process resumes its execution. 42 Then at the next error or break or ..., valgrind calls gdbserver again. 43 A resume reply packet must then be built to inform GDB that the 44 resume request is finished. 45 resume_reply_packet_needed records the fact that the next call to gdbserver 46 must send a resume packet to gdb. */ 47 static Bool resume_reply_packet_needed = False; 48 49 VG_MINIMAL_JMP_BUF(toplevel); 50 51 /* Decode a qXfer read request. Return 0 if everything looks OK, 52 or -1 otherwise. */ 53 54 static 55 int decode_xfer_read (char *buf, char **annex, CORE_ADDR *ofs, unsigned int *len) 56 { 57 /* Extract and NUL-terminate the annex. */ 58 *annex = buf; 59 while (*buf && *buf != ':') 60 buf++; 61 if (*buf == '\0') 62 return -1; 63 *buf++ = 0; 64 65 /* After the read/write marker and annex, qXfer looks like a 66 traditional 'm' packet. */ 67 decode_m_packet (buf, ofs, len); 68 69 return 0; 70 } 71 72 /* Write the response to a successful qXfer read. Returns the 73 length of the (binary) data stored in BUF, corresponding 74 to as much of DATA/LEN as we could fit. IS_MORE controls 75 the first character of the response. */ 76 static 77 int write_qxfer_response (char *buf, unsigned char *data, int len, int is_more) 78 { 79 int out_len; 80 81 if (is_more) 82 buf[0] = 'm'; 83 else 84 buf[0] = 'l'; 85 86 return remote_escape_output (data, len, (unsigned char *) buf + 1, &out_len, 87 PBUFSIZ - POVERHSIZ - 1) + 1; 88 } 89 90 static Bool initial_valgrind_sink_saved = False; 91 /* True <=> valgrind log sink saved in initial_valgrind_sink */ 92 static OutputSink initial_valgrind_sink; 93 94 static Bool command_output_to_log = False; 95 /* True <=> command output goes to log instead of gdb */ 96 97 void reset_valgrind_sink(char *info) 98 { 99 if (VG_(log_output_sink).fd != initial_valgrind_sink.fd 100 && initial_valgrind_sink_saved) { 101 VG_(log_output_sink).fd = initial_valgrind_sink.fd; 102 VG_(umsg) ("Reset valgrind output to log (%s)\n", 103 (info = NULL ? "" : info)); 104 } 105 } 106 107 static 108 void kill_request (char *msg) 109 { 110 VG_(umsg) ("%s", msg); 111 remote_close(); 112 VG_(exit) (0); 113 } 114 115 /* handle_gdb_valgrind_command handles the provided mon string command. 116 If command is recognised, return 1 else return 0. 117 Note that in case of ambiguous command, 1 is returned. 118 119 *sink_wanted_at_return is modified if one of the commands 120 'v.set *_output' is handled. 121 */ 122 static 123 int handle_gdb_valgrind_command (char* mon, OutputSink* sink_wanted_at_return) 124 { 125 UWord ret = 0; 126 char s[strlen(mon)+1]; /* copy for strtok_r */ 127 char* wcmd; 128 Char* ssaveptr; 129 char* endptr; 130 int kwdid; 131 int int_value; 132 133 vg_assert (initial_valgrind_sink_saved); 134 135 strcpy (s, mon); 136 wcmd = strtok_r (s, " ", &ssaveptr); 137 /* NB: if possible, avoid introducing a new command below which 138 starts with the same 3 first letters as an already existing 139 command. This ensures a shorter abbreviation for the user. */ 140 switch (VG_(keyword_id) ("help v.set v.info v.wait v.kill v.translate", 141 wcmd, kwd_report_duplicated_matches)) { 142 case -2: 143 ret = 1; 144 break; 145 case -1: 146 break; 147 case 0: /* help */ 148 ret = 1; 149 wcmd = strtok_r (NULL, " ", &ssaveptr); 150 if (wcmd == NULL) { 151 int_value = 0; 152 } else { 153 switch (VG_(keyword_id) ("debug", wcmd, kwd_report_all)) { 154 case -2: int_value = 0; break; 155 case -1: int_value = 0; break; 156 case 0: int_value = 1; break; 157 default: tl_assert (0); 158 } 159 } 160 161 VG_(gdb_printf) ( 162 "general valgrind monitor commands:\n" 163 " help [debug] : monitor command help. With debug: + debugging commands\n" 164 " v.wait [<ms>] : sleep <ms> (default 0) then continue\n" 165 " v.info all_errors : show all errors found so far\n" 166 " v.info last_error : show last error found\n" 167 " v.info n_errs_found : show the nr of errors found so far\n" 168 " v.kill : kill the Valgrind process\n" 169 " v.set gdb_output : set valgrind output to gdb\n" 170 " v.set log_output : set valgrind output to log\n" 171 " v.set mixed_output : set valgrind output to log, interactive output to gdb\n" 172 " v.set vgdb-error <errornr> : debug me at error >= <errornr> \n"); 173 if (int_value) { VG_(gdb_printf) ( 174 "debugging valgrind internals monitor commands:\n" 175 " v.info gdbserver_status : show gdbserver status\n" 176 " v.info memory [aspacemgr] : show valgrind heap memory stats\n" 177 " (with aspacemgr arg, also shows valgrind segments on log ouput)\n" 178 " v.info scheduler : show valgrind thread state and stacktrace\n" 179 " v.set debuglog <level> : set valgrind debug log level to <level>\n" 180 " v.translate <addr> [<traceflags>] : debug translation of <addr> with <traceflags>\n" 181 " (default traceflags 0b00100000 : show after instrumentation)\n" 182 " An additional flag 0b100000000 allows to show gdbserver instrumentation\n"); 183 } 184 break; 185 case 1: /* v.set */ 186 ret = 1; 187 wcmd = strtok_r (NULL, " ", &ssaveptr); 188 switch (kwdid = VG_(keyword_id) 189 ("vgdb-error debuglog gdb_output log_output mixed_output", 190 wcmd, kwd_report_all)) { 191 case -2: 192 case -1: 193 break; 194 case 0: /* vgdb-error */ 195 case 1: /* debuglog */ 196 wcmd = strtok_r (NULL, " ", &ssaveptr); 197 if (wcmd == NULL) { 198 int_value = 0; 199 endptr = "empty"; /* to report an error below */ 200 } else { 201 int_value = strtol (wcmd, &endptr, 10); 202 } 203 if (*endptr != '\0') { 204 VG_(gdb_printf) ("missing or malformed integer value\n"); 205 } else if (kwdid == 0) { 206 VG_(gdb_printf) ("vgdb-error value changed from %d to %d\n", 207 VG_(dyn_vgdb_error), int_value); 208 VG_(dyn_vgdb_error) = int_value; 209 } else if (kwdid == 1) { 210 VG_(gdb_printf) ("debuglog value changed from %d to %d\n", 211 VG_(debugLog_getLevel)(), int_value); 212 VG_(debugLog_startup) (int_value, "gdbsrv"); 213 } else { 214 vg_assert (0); 215 } 216 break; 217 case 2: /* gdb_output */ 218 (*sink_wanted_at_return).fd = -2; 219 command_output_to_log = False; 220 VG_(gdb_printf) ("valgrind output will go to gdb\n"); 221 break; 222 case 3: /* log_output */ 223 (*sink_wanted_at_return).fd = initial_valgrind_sink.fd; 224 command_output_to_log = True; 225 VG_(gdb_printf) ("valgrind output will go to log\n"); 226 break; 227 case 4: /* mixed output */ 228 (*sink_wanted_at_return).fd = initial_valgrind_sink.fd; 229 command_output_to_log = False; 230 VG_(gdb_printf) 231 ("valgrind output will go to log, interactive output will go to gdb\n"); 232 break; 233 default: 234 vg_assert (0); 235 } 236 break; 237 case 2: /* v.info */ { 238 ret = 1; 239 wcmd = strtok_r (NULL, " ", &ssaveptr); 240 switch (kwdid = VG_(keyword_id) 241 ("all_errors n_errs_found last_error gdbserver_status memory" 242 " scheduler", 243 wcmd, kwd_report_all)) { 244 case -2: 245 case -1: 246 break; 247 case 0: // all_errors 248 // A verbosity of minimum 2 is needed to show the errors. 249 VG_(show_all_errors)(/* verbosity */ 2, /* xml */ False); 250 break; 251 case 1: // n_errs_found 252 VG_(gdb_printf) ("n_errs_found %d n_errs_shown %d (vgdb-error %d)\n", 253 VG_(get_n_errs_found) (), 254 VG_(get_n_errs_shown) (), 255 VG_(dyn_vgdb_error)); 256 break; 257 case 2: // last_error 258 VG_(show_last_error)(); 259 break; 260 case 3: // gdbserver_status 261 VG_(gdbserver_status_output)(); 262 break; 263 case 4: /* memory */ 264 VG_(print_all_arena_stats) (); 265 if (VG_(clo_profile_heap)) 266 VG_(print_arena_cc_analysis) (); 267 wcmd = strtok_r (NULL, " ", &ssaveptr); 268 if (wcmd != NULL) { 269 switch (VG_(keyword_id) ("aspacemgr", wcmd, kwd_report_all)) { 270 case -2: 271 case -1: break; 272 case 0: 273 VG_(am_show_nsegments) (0, "gdbserver v.info memory aspacemgr"); 274 break; 275 default: tl_assert (0); 276 } 277 } 278 279 ret = 1; 280 break; 281 case 5: /* scheduler */ 282 VG_(show_sched_status) (); 283 ret = 1; 284 break; 285 default: 286 vg_assert(0); 287 } 288 break; 289 } 290 case 3: /* v.wait */ 291 wcmd = strtok_r (NULL, " ", &ssaveptr); 292 if (wcmd != NULL) { 293 int_value = strtol (wcmd, &endptr, 10); 294 VG_(gdb_printf) ("gdbserver: continuing in %d ms ...\n", int_value); 295 VG_(poll)(NULL, 0, int_value); 296 } 297 VG_(gdb_printf) ("gdbserver: continuing after wait ...\n"); 298 ret = 1; 299 break; 300 case 4: /* v.kill */ 301 kill_request ("monitor command request to kill this process\n"); 302 break; 303 case 5: { /* v.translate */ 304 Addr address; 305 SizeT verbosity = 0x20; 306 307 ret = 1; 308 309 VG_(strtok_get_address_and_size) (&address, &verbosity, &ssaveptr); 310 if (address != (Addr) 0 || verbosity != 0) { 311 /* we need to force the output to log for the translation trace, 312 as low level VEX tracing cannot be redirected to gdb. */ 313 int saved_command_output_to_log = command_output_to_log; 314 int saved_fd = VG_(log_output_sink).fd; 315 Bool single_stepping_on_entry = valgrind_single_stepping(); 316 int vex_verbosity = verbosity & 0xff; 317 VG_(log_output_sink).fd = initial_valgrind_sink.fd; 318 if ((verbosity & 0x100) && !single_stepping_on_entry) { 319 valgrind_set_single_stepping(True); 320 // to force gdbserver instrumentation. 321 } 322 # if defined(VGA_arm) 323 // on arm, we need to (potentially) convert this address 324 // to the thumb form. 325 address = thumb_pc (address); 326 # endif 327 328 VG_(translate) ( 0 /* dummy ThreadId; irrelevant due to debugging*/, 329 address, 330 /*debugging*/True, 331 (Int) vex_verbosity, 332 /*bbs_done*/0, 333 /*allow redir?*/True); 334 if ((verbosity & 0x100) && !single_stepping_on_entry) { 335 valgrind_set_single_stepping(False); 336 // reset single stepping. 337 } 338 command_output_to_log = saved_command_output_to_log; 339 VG_(log_output_sink).fd = saved_fd; 340 } 341 break; 342 } 343 344 default: 345 vg_assert (0); 346 } 347 return ret; 348 } 349 350 /* handle_gdb_monitor_command handles the provided mon string command, 351 which can be either a "standard" valgrind monitor command 352 or a tool specific monitor command. 353 If command recognised, return 1 else return 0. 354 Note that in case of ambiguous command, 1 is returned. 355 */ 356 static 357 int handle_gdb_monitor_command (char* mon) 358 { 359 UWord ret = 0; 360 UWord tool_ret = 0; 361 // initially, we assume that when returning, the desired sink is the 362 // one we have when entering. It can however be changed by the standard 363 // valgrind command handling. 364 OutputSink sink_wanted_at_return = VG_(log_output_sink); 365 366 if (!initial_valgrind_sink_saved) { 367 /* first time we enter here, we save the valgrind default log sink */ 368 initial_valgrind_sink = sink_wanted_at_return; 369 initial_valgrind_sink_saved = True; 370 } 371 372 if (!command_output_to_log) 373 VG_(log_output_sink).fd = -2; /* redirect to monitor_output */ 374 375 ret = handle_gdb_valgrind_command (mon, &sink_wanted_at_return); 376 377 /* Even if command was recognised by valgrind core, we call the 378 tool command handler : this is needed to handle help command 379 and/or to let the tool do some additional processing of a 380 valgrind standard command. Note however that if valgrind 381 recognised the command, we will always return success. */ 382 if (VG_(needs).client_requests) { 383 /* If the tool reports an error when handling a monitor command, 384 we need to avoid calling gdbserver during this command 385 handling. So, we temporarily set VG_(dyn_vgdb_error) to 386 a huge value to ensure m_errormgr.c does not call gdbserver. */ 387 Int save_dyn_vgdb_error = VG_(dyn_vgdb_error); 388 UWord arg[2]; 389 VG_(dyn_vgdb_error) = 999999999; 390 arg[0] = (UWord) VG_USERREQ__GDB_MONITOR_COMMAND; 391 arg[1] = (UWord) mon; 392 VG_TDICT_CALL(tool_handle_client_request, VG_(running_tid), arg, 393 &tool_ret); 394 VG_(dyn_vgdb_error) = save_dyn_vgdb_error; 395 } 396 397 /* restore or set the desired output */ 398 VG_(log_output_sink).fd = sink_wanted_at_return.fd; 399 if (ret | tool_ret) 400 return 1; 401 else 402 return 0; 403 } 404 405 406 /* Handle all of the extended 'Q' packets. */ 407 static 408 void handle_set (char *arg_own_buf, int *new_packet_len_p) 409 { 410 if (strcmp ("QStartNoAckMode", arg_own_buf) == 0) { 411 noack_mode = True; 412 write_ok (arg_own_buf); 413 return; 414 } 415 416 if (strncmp ("QPassSignals:", arg_own_buf, 13) == 0) { 417 int i; 418 char *from, *to; 419 char *end = arg_own_buf + strlen(arg_own_buf); 420 CORE_ADDR sig; 421 for (i = 0; i < TARGET_SIGNAL_LAST; i++) 422 pass_signals[i] = 0; 423 424 from = arg_own_buf + 13; 425 while (from < end) { 426 to = strchr(from, ';'); 427 if (to == NULL) to = end; 428 decode_address (&sig, from, to - from); 429 pass_signals[(int)sig] = 1; 430 dlog(1, "pass_signal gdb_nr %d %s\n", 431 (int)sig, target_signal_to_name(sig)); 432 from = to; 433 if (*from == ';') from++; 434 } 435 write_ok (arg_own_buf); 436 return; 437 } 438 /* Otherwise we didn't know what packet it was. Say we didn't 439 understand it. */ 440 arg_own_buf[0] = 0; 441 } 442 443 /* Handle all of the extended 'q' packets. */ 444 static 445 void handle_query (char *arg_own_buf, int *new_packet_len_p) 446 { 447 static struct inferior_list_entry *thread_ptr; 448 449 /* qRcmd, monitor command handling. */ 450 if (strncmp ("qRcmd,", arg_own_buf, 6) == 0) { 451 char *p = arg_own_buf + 6; 452 int cmdlen = strlen(p)/2; 453 char cmd[cmdlen+1]; 454 455 if (unhexify (cmd, p, cmdlen) != cmdlen) { 456 write_enn (arg_own_buf); 457 return; 458 } 459 cmd[cmdlen] = '\0'; 460 461 if (handle_gdb_monitor_command (cmd)) { 462 /* In case the command is from a standalone vgdb, 463 connection will be closed soon => flush the output. */ 464 VG_(message_flush) (); 465 write_ok (arg_own_buf); 466 return; 467 } else { 468 /* cmd not recognised */ 469 VG_(gdb_printf) 470 ("command '%s' not recognised\n" 471 "In gdb, try 'monitor help'\n" 472 "In a shell, try 'vgdb help'\n", 473 cmd); 474 write_ok (arg_own_buf); 475 return; 476 } 477 } 478 479 /* provide some valgrind specific info in return to qThreadExtraInfo. */ 480 if (strncmp ("qThreadExtraInfo,", arg_own_buf, 17) == 0) { 481 unsigned long gdb_id; 482 struct thread_info *ti; 483 ThreadState *tst; 484 char status[100]; 485 486 gdb_id = strtoul (&arg_own_buf[17], NULL, 16); 487 ti = gdb_id_to_thread (gdb_id); 488 if (ti != NULL) { 489 tst = (ThreadState *) inferior_target_data (ti); 490 /* Additional info is the tid and the thread status. */ 491 VG_(snprintf) (status, sizeof(status), "tid %d %s", 492 tst->tid, 493 VG_(name_of_ThreadStatus)(tst->status)); 494 hexify (arg_own_buf, status, strlen(status)); 495 return; 496 } else { 497 write_enn (arg_own_buf); 498 return; 499 } 500 } 501 502 if (strcmp ("qAttached", arg_own_buf) == 0) { 503 /* tell gdb to always detach, never kill the process */ 504 arg_own_buf[0] = '1'; 505 arg_own_buf[1] = 0; 506 return; 507 } 508 509 if (strcmp ("qSymbol::", arg_own_buf) == 0) { 510 /* We have no symbol to read. */ 511 write_ok (arg_own_buf); 512 return; 513 } 514 515 if (strcmp ("qfThreadInfo", arg_own_buf) == 0) { 516 thread_ptr = all_threads.head; 517 VG_(sprintf) (arg_own_buf, "m%x", 518 thread_to_gdb_id ((struct thread_info *)thread_ptr)); 519 thread_ptr = thread_ptr->next; 520 return; 521 } 522 523 if (strcmp ("qsThreadInfo", arg_own_buf) == 0) { 524 if (thread_ptr != NULL) { 525 VG_(sprintf) (arg_own_buf, "m%x", 526 thread_to_gdb_id ((struct thread_info *)thread_ptr)); 527 thread_ptr = thread_ptr->next; 528 return; 529 } else { 530 VG_(sprintf) (arg_own_buf, "l"); 531 return; 532 } 533 } 534 535 if (valgrind_target_xml(VG_(clo_vgdb_shadow_registers)) != NULL 536 && strncmp ("qXfer:features:read:", arg_own_buf, 20) == 0) { 537 CORE_ADDR ofs; 538 unsigned int len, doc_len; 539 char *annex = NULL; 540 // First, the annex is extracted from the packet received. 541 // Then, it is replaced by the corresponding file name. 542 int fd; 543 544 /* Grab the annex, offset, and length. */ 545 if (decode_xfer_read (arg_own_buf + 20, &annex, &ofs, &len) < 0) { 546 strcpy (arg_own_buf, "E00"); 547 return; 548 } 549 550 if (strcmp (annex, "target.xml") == 0) { 551 annex = valgrind_target_xml(VG_(clo_vgdb_shadow_registers)); 552 if (annex != NULL && VG_(clo_vgdb_shadow_registers)) { 553 /* Ensure the shadow registers are initialized. */ 554 initialize_shadow_low(True); 555 } 556 if (annex == NULL) { 557 strcpy (arg_own_buf, "E00"); 558 return; 559 } 560 } 561 562 { 563 char doc[VG_(strlen)(VG_(libdir)) + 1 + VG_(strlen)(annex) + 1]; 564 struct vg_stat stat_doc; 565 char toread[len]; 566 int len_read; 567 568 VG_(sprintf)(doc, "%s/%s", VG_(libdir), annex); 569 fd = VG_(fd_open) (doc, VKI_O_RDONLY, 0); 570 if (fd == -1) { 571 strcpy (arg_own_buf, "E00"); 572 return; 573 } 574 if (VG_(fstat) (fd, &stat_doc) != 0) { 575 VG_(close) (fd); 576 strcpy (arg_own_buf, "E00"); 577 return; 578 } 579 doc_len = stat_doc.size; 580 581 if (len > PBUFSIZ - POVERHSIZ) 582 len = PBUFSIZ - POVERHSIZ; 583 584 if (ofs > doc_len) { 585 write_enn (arg_own_buf); 586 VG_(close) (fd); 587 return; 588 } 589 VG_(lseek) (fd, ofs, VKI_SEEK_SET); 590 len_read = VG_(read) (fd, toread, len); 591 *new_packet_len_p = write_qxfer_response (arg_own_buf, toread, 592 len_read, ofs + len_read < doc_len); 593 VG_(close) (fd); 594 return; 595 } 596 } 597 598 if (strncmp ("qXfer:auxv:read:", arg_own_buf, 16) == 0) { 599 unsigned char *data; 600 int n; 601 CORE_ADDR ofs; 602 unsigned int len; 603 char *annex; 604 605 /* Reject any annex; grab the offset and length. */ 606 if (decode_xfer_read (arg_own_buf + 16, &annex, &ofs, &len) < 0 607 || annex[0] != '\0') { 608 strcpy (arg_own_buf, "E00"); 609 return; 610 } 611 612 if (len > PBUFSIZ - 2) 613 len = PBUFSIZ - 2; 614 data = malloc (len); 615 616 { 617 UWord *client_auxv = VG_(client_auxv); 618 unsigned int client_auxv_len = 0; 619 while (*client_auxv != 0) { 620 dlog(4, "auxv %lld %llx\n", 621 (ULong)*client_auxv, 622 (ULong)*(client_auxv+1)); 623 client_auxv++; 624 client_auxv++; 625 client_auxv_len += 2 * sizeof(UWord); 626 } 627 client_auxv_len += 2 * sizeof(UWord); 628 dlog(4, "auxv len %d\n", client_auxv_len); 629 630 if (ofs >= client_auxv_len) 631 n = -1; 632 else { 633 n = client_auxv_len - ofs; 634 VG_(memcpy) (data, (unsigned char *) VG_(client_auxv), n); 635 } 636 } 637 638 if (n < 0) 639 write_enn (arg_own_buf); 640 else if (n > len) 641 *new_packet_len_p = write_qxfer_response (arg_own_buf, data, len, 1); 642 else 643 *new_packet_len_p = write_qxfer_response (arg_own_buf, data, n, 0); 644 645 free (data); 646 647 return; 648 } 649 650 651 /* Protocol features query. */ 652 if (strncmp ("qSupported", arg_own_buf, 10) == 0 653 && (arg_own_buf[10] == ':' || arg_own_buf[10] == '\0')) { 654 VG_(sprintf) (arg_own_buf, "PacketSize=%x", PBUFSIZ - 1); 655 /* Note: max packet size including frame and checksum, but without 656 trailing null byte, which is not sent/received. */ 657 658 strcat (arg_own_buf, ";QStartNoAckMode+"); 659 strcat (arg_own_buf, ";QPassSignals+"); 660 if (VG_(client_auxv)) 661 strcat (arg_own_buf, ";qXfer:auxv:read+"); 662 663 if (valgrind_target_xml(VG_(clo_vgdb_shadow_registers)) != NULL) { 664 strcat (arg_own_buf, ";qXfer:features:read+"); 665 /* if a new gdb connects to us, we have to reset the register 666 set to the normal register sets to allow this new gdb to 667 decide to use or not the shadow registers. 668 669 Note that the reset is only done for gdb that are sending 670 qSupported packets. If a user first connected with a recent 671 gdb using shadow registers and then with a very old gdb 672 that does not use qSupported packet, then the old gdb will 673 not properly connect. */ 674 initialize_shadow_low(False); 675 } 676 return; 677 } 678 679 /* Otherwise we didn't know what packet it was. Say we didn't 680 understand it. */ 681 arg_own_buf[0] = 0; 682 } 683 684 /* Handle all of the extended 'v' packets. */ 685 static 686 void handle_v_requests (char *arg_own_buf, char *status, int *zignal) 687 { 688 /* vcont packet code from gdb 6.6 removed */ 689 690 /* Otherwise we didn't know what packet it was. Say we didn't 691 understand it. */ 692 arg_own_buf[0] = 0; 693 return; 694 } 695 696 static 697 void myresume (int step, int sig) 698 { 699 struct thread_resume resume_info[2]; 700 int n = 0; 701 702 if (step || sig) { 703 resume_info[0].step = step; 704 resume_info[0].sig = sig; 705 n++; 706 } 707 resume_info[n].step = 0; 708 resume_info[n].sig = 0; 709 710 resume_reply_packet_needed = True; 711 valgrind_resume (resume_info); 712 } 713 714 /* server_main global variables */ 715 static char *own_buf; 716 static unsigned char *mem_buf; 717 718 void gdbserver_init (void) 719 { 720 dlog(1, "gdbserver_init gdbserver embedded in valgrind: %s\n", version); 721 noack_mode = False; 722 valgrind_initialize_target (); 723 // After a fork, gdbserver_init can be called again. 724 // We do not have to re-malloc the buffers in such a case. 725 if (own_buf == NULL) 726 own_buf = malloc (PBUFSIZ); 727 if (mem_buf == NULL) 728 mem_buf = malloc (PBUFSIZ); 729 } 730 731 void gdbserver_terminate (void) 732 { 733 /* last call to gdbserver is cleanup call */ 734 if (VG_MINIMAL_SETJMP(toplevel)) { 735 dlog(0, "error caused VG_MINIMAL_LONGJMP to gdbserver_terminate\n"); 736 return; 737 } 738 remote_close(); 739 } 740 741 void server_main (void) 742 { 743 static char status; 744 static int zignal; 745 746 char ch; 747 int i = 0; 748 unsigned int len; 749 CORE_ADDR mem_addr; 750 751 zignal = valgrind_wait (&status); 752 if (VG_MINIMAL_SETJMP(toplevel)) { 753 dlog(0, "error caused VG_MINIMAL_LONGJMP to server_main\n"); 754 } 755 while (1) { 756 unsigned char sig; 757 int packet_len; 758 int new_packet_len = -1; 759 760 if (resume_reply_packet_needed) { 761 /* Send the resume reply to reply to last GDB resume 762 request. */ 763 resume_reply_packet_needed = False; 764 prepare_resume_reply (own_buf, status, zignal); 765 putpkt (own_buf); 766 } 767 768 packet_len = getpkt (own_buf); 769 if (packet_len <= 0) 770 break; 771 772 i = 0; 773 ch = own_buf[i++]; 774 switch (ch) { 775 case 'Q': 776 handle_set (own_buf, &new_packet_len); 777 break; 778 case 'q': 779 handle_query (own_buf, &new_packet_len); 780 break; 781 case 'd': 782 /* set/unset debugging is done through valgrind debug level. */ 783 own_buf[0] = '\0'; 784 break; 785 case 'D': 786 reset_valgrind_sink("gdb detaching from process"); 787 788 /* When detaching or kill the process, gdb expects to get 789 an packet OK back. Any other output will make gdb 790 believes detach did not work. */ 791 write_ok (own_buf); 792 putpkt (own_buf); 793 remote_finish (reset_after_error); 794 remote_open (VG_(clo_vgdb_prefix)); 795 myresume (0, 0); 796 resume_reply_packet_needed = False; 797 return; 798 case '!': 799 /* We can not use the extended protocol with valgrind, 800 because we can not restart the running 801 program. So return unrecognized. */ 802 own_buf[0] = '\0'; 803 break; 804 case '?': 805 prepare_resume_reply (own_buf, status, zignal); 806 break; 807 case 'H': 808 if (own_buf[1] == 'c' || own_buf[1] == 'g' || own_buf[1] == 's') { 809 unsigned long gdb_id, thread_id; 810 811 gdb_id = strtoul (&own_buf[2], NULL, 16); 812 thread_id = gdb_id_to_thread_id (gdb_id); 813 if (thread_id == 0) { 814 write_enn (own_buf); 815 break; 816 } 817 818 if (own_buf[1] == 'g') { 819 general_thread = thread_id; 820 set_desired_inferior (1); 821 } else if (own_buf[1] == 'c') { 822 cont_thread = thread_id; 823 } else if (own_buf[1] == 's') { 824 step_thread = thread_id; 825 } 826 827 write_ok (own_buf); 828 } else { 829 /* Silently ignore it so that gdb can extend the protocol 830 without compatibility headaches. */ 831 own_buf[0] = '\0'; 832 } 833 break; 834 case 'g': 835 set_desired_inferior (1); 836 registers_to_string (own_buf); 837 break; 838 case 'G': 839 set_desired_inferior (1); 840 registers_from_string (&own_buf[1]); 841 write_ok (own_buf); 842 break; 843 case 'P': { 844 int regno; 845 char *regbytes; 846 Bool mod; 847 ThreadState *tst; 848 regno = strtol(&own_buf[1], NULL, 16); 849 regbytes = strchr(&own_buf[0], '=') + 1; 850 set_desired_inferior (1); 851 tst = (ThreadState *) inferior_target_data (current_inferior); 852 /* Only accept changing registers in "runnable state3. 853 In fact, it would be ok to change most of the registers 854 except a few "sensitive" registers such as the PC, SP, BP. 855 We assume we do not need to very specific here, and that we 856 can just refuse all of these. */ 857 if (tst->status == VgTs_Runnable || tst->status == VgTs_Yielding) { 858 supply_register_from_string (regno, regbytes, &mod); 859 write_ok (own_buf); 860 } else { 861 /* at least from gdb 6.6 onwards, an E. error 862 reply is shown to the user. So, we do an error 863 msg which both is accepted by gdb as an error msg 864 and is readable by the user. */ 865 VG_(sprintf) 866 (own_buf, 867 "E.\n" 868 "ERROR changing register %s regno %d\n" 869 "gdb commands changing registers (pc, sp, ...) (e.g. 'jump',\n" 870 "set pc, calling from gdb a function in the debugged process, ...)\n" 871 "can only be accepted if the thread is VgTs_Runnable or VgTs_Yielding state\n" 872 "Thread status is %s\n", 873 find_register_by_number (regno)->name, regno, 874 VG_(name_of_ThreadStatus)(tst->status)); 875 if (VG_(clo_verbosity) > 1) 876 VG_(umsg) ("%s\n", own_buf); 877 } 878 break; 879 } 880 case 'm': 881 decode_m_packet (&own_buf[1], &mem_addr, &len); 882 if (valgrind_read_memory (mem_addr, mem_buf, len) == 0) 883 convert_int_to_ascii (mem_buf, own_buf, len); 884 else 885 write_enn (own_buf); 886 break; 887 case 'M': 888 decode_M_packet (&own_buf[1], &mem_addr, &len, mem_buf); 889 if (valgrind_write_memory (mem_addr, mem_buf, len) == 0) 890 write_ok (own_buf); 891 else 892 write_enn (own_buf); 893 break; 894 case 'X': 895 if (decode_X_packet (&own_buf[1], packet_len - 1, 896 &mem_addr, &len, mem_buf) < 0 897 || valgrind_write_memory (mem_addr, mem_buf, len) != 0) 898 write_enn (own_buf); 899 else 900 write_ok (own_buf); 901 break; 902 case 'C': 903 convert_ascii_to_int (own_buf + 1, &sig, 1); 904 if (target_signal_to_host_p (sig)) 905 zignal = target_signal_to_host (sig); 906 else 907 zignal = 0; 908 set_desired_inferior (0); 909 myresume (0, zignal); 910 return; // return control to valgrind 911 case 'S': 912 convert_ascii_to_int (own_buf + 1, &sig, 1); 913 if (target_signal_to_host_p (sig)) 914 zignal = target_signal_to_host (sig); 915 else 916 zignal = 0; 917 set_desired_inferior (0); 918 myresume (1, zignal); 919 return; // return control to valgrind 920 case 'c': 921 set_desired_inferior (0); 922 myresume (0, 0); 923 return; // return control to valgrind 924 case 's': 925 set_desired_inferior (0); 926 myresume (1, 0); 927 return; // return control to valgrind 928 case 'Z': { 929 char *lenptr; 930 char *dataptr; 931 CORE_ADDR addr = strtoul (&own_buf[3], &lenptr, 16); 932 int zlen = strtol (lenptr + 1, &dataptr, 16); 933 char type = own_buf[1]; 934 935 if (type < '0' || type > '4') { 936 /* Watchpoint command type unrecognized. */ 937 own_buf[0] = '\0'; 938 } else { 939 int res; 940 941 res = valgrind_insert_watchpoint (type, addr, zlen); 942 if (res == 0) 943 write_ok (own_buf); 944 else if (res == 1) 945 /* Unsupported. */ 946 own_buf[0] = '\0'; 947 else 948 write_enn (own_buf); 949 } 950 break; 951 } 952 case 'z': { 953 char *lenptr; 954 char *dataptr; 955 CORE_ADDR addr = strtoul (&own_buf[3], &lenptr, 16); 956 int zlen = strtol (lenptr + 1, &dataptr, 16); 957 char type = own_buf[1]; 958 959 if (type < '0' || type > '4') { 960 /* Watchpoint command type unrecognized. */ 961 own_buf[0] = '\0'; 962 } else { 963 int res; 964 965 res = valgrind_remove_watchpoint (type, addr, zlen); 966 if (res == 0) 967 write_ok (own_buf); 968 else if (res == 1) 969 /* Unsupported. */ 970 own_buf[0] = '\0'; 971 else 972 write_enn (own_buf); 973 } 974 break; 975 } 976 case 'k': 977 kill_request("Gdb request to kill this process\n"); 978 break; 979 case 'T': { 980 unsigned long gdb_id, thread_id; 981 982 gdb_id = strtoul (&own_buf[1], NULL, 16); 983 thread_id = gdb_id_to_thread_id (gdb_id); 984 if (thread_id == 0) { 985 write_enn (own_buf); 986 break; 987 } 988 989 if (valgrind_thread_alive (thread_id)) 990 write_ok (own_buf); 991 else 992 write_enn (own_buf); 993 break; 994 } 995 case 'R': 996 /* Restarting the inferior is only supported in the 997 extended protocol. 998 => It is a request we don't understand. Respond with an 999 empty packet so that gdb knows that we don't support this 1000 request. */ 1001 own_buf[0] = '\0'; 1002 break; 1003 case 'v': 1004 /* Extended (long) request. */ 1005 handle_v_requests (own_buf, &status, &zignal); 1006 break; 1007 default: 1008 /* It is a request we don't understand. Respond with an 1009 empty packet so that gdb knows that we don't support this 1010 request. */ 1011 own_buf[0] = '\0'; 1012 break; 1013 } 1014 1015 if (new_packet_len != -1) 1016 putpkt_binary (own_buf, new_packet_len); 1017 else 1018 putpkt (own_buf); 1019 1020 if (status == 'W') 1021 VG_(umsg) ("\nChild exited with status %d\n", zignal); 1022 if (status == 'X') 1023 VG_(umsg) ("\nChild terminated with signal = 0x%x (%s)\n", 1024 target_signal_to_host (zignal), 1025 target_signal_to_name (zignal)); 1026 if (status == 'W' || status == 'X') { 1027 VG_(umsg) ("Process exiting\n"); 1028 VG_(exit) (0); 1029 } 1030 } 1031 1032 /* We come here when getpkt fails => close the connection, 1033 and re-open. Then return control to valgrind. 1034 We return the control to valgrind as we assume that 1035 the connection was closed due to vgdb having finished 1036 to execute a command. */ 1037 if (VG_(clo_verbosity) > 1) 1038 VG_(umsg) ("Remote side has terminated connection. " 1039 "GDBserver will reopen the connection.\n"); 1040 remote_finish (reset_after_error); 1041 remote_open (VG_(clo_vgdb_prefix)); 1042 myresume (0, 0); 1043 resume_reply_packet_needed = False; 1044 return; 1045 } 1046
