gdbstub.c

   1 /*
   2  * gdb server stub
   3  *
   4  * Copyright (c) 2003-2005 Fabrice Bellard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20 #include "config.h"
  21 #ifdef CONFIG_USER_ONLY
  22 #include <stdlib.h>
  23 #include <stdio.h>
  24 #include <stdarg.h>
  25 #include <string.h>
  26 #include <errno.h>
  27 #include <unistd.h>
  28 #include <fcntl.h>
  29
  30 #include "qemu.h"
  31 #else
  32 #include "vl.h"
  33 #endif
  34
  35 #include "qemu_socket.h"
  36 #ifdef _WIN32
  37 /* XXX: these constants may be independent of the host ones even for Unix */
  38 #ifndef SIGTRAP
  39 #define SIGTRAP 5
  40 #endif
  41 #ifndef SIGINT
  42 #define SIGINT 2
  43 #endif
  44 #else
  45 #include <signal.h>
  46 #endif
  47
  48 //#define DEBUG_GDB
  49
  50 enum RSState {
  51     RS_IDLE,
  52     RS_GETLINE,
  53     RS_CHKSUM1,
  54     RS_CHKSUM2,
  55 };
  56 /* XXX: This is not thread safe.  Do we care?  */
  57 static int gdbserver_fd = -1;
  58
  59 typedef struct GDBState {
  60     CPUState *env; /* current CPU */
  61     enum RSState state; /* parsing state */
  62     int fd;
  63     char line_buf[4096];
  64     int line_buf_index;
  65     int line_csum;
  66 #ifdef CONFIG_USER_ONLY
  67     int running_state;
  68 #endif
  69 } GDBState;
  70
  71 #ifdef CONFIG_USER_ONLY
  72 /* XXX: remove this hack.  */
  73 static GDBState gdbserver_state;
  74 #endif
  75
  76 static int get_char(GDBState *s)
  77 {
  78     uint8_t ch;
  79     int ret;
  80
  81     for(;;) {
  82         ret = recv(s->fd, &ch, 1, 0);
  83         if (ret < 0) {
  84             if (errno != EINTR && errno != EAGAIN)
  85                 return -1;
  86         } else if (ret == 0) {
  87             return -1;
  88         } else {
  89             break;
  90         }
  91     }
  92     return ch;
  93 }
  94
  95 static void put_buffer(GDBState *s, const uint8_t *buf, int len)
  96 {
  97     int ret;
  98
  99     while (len > 0) {
 100         ret = send(s->fd, buf, len, 0);
 101         if (ret < 0) {
 102             if (errno != EINTR && errno != EAGAIN)
 103                 return;
 104         } else {
 105             buf += ret;
 106             len -= ret;
 107         }
 108     }
 109 }
 110
 111 static inline int fromhex(int v)
 112 {
 113     if (v >= '0' && v <= '9')
 114         return v - '0';
 115     else if (v >= 'A' && v <= 'F')
 116         return v - 'A' + 10;
 117     else if (v >= 'a' && v <= 'f')
 118         return v - 'a' + 10;
 119     else
 120         return 0;
 121 }
 122
 123 static inline int tohex(int v)
 124 {
 125     if (v < 10)
 126         return v + '0';
 127     else
 128         return v - 10 + 'a';
 129 }
 130
 131 static void memtohex(char *buf, const uint8_t *mem, int len)
 132 {
 133     int i, c;
 134     char *q;
 135     q = buf;
 136     for(i = 0; i < len; i++) {
 137         c = mem[i];
 138         *q++ = tohex(c >> 4);
 139         *q++ = tohex(c & 0xf);
 140     }
 141     *q = '\0';
 142 }
 143
 144 static void hextomem(uint8_t *mem, const char *buf, int len)
 145 {
 146     int i;
 147
 148     for(i = 0; i < len; i++) {
 149         mem[i] = (fromhex(buf[0]) << 4) | fromhex(buf[1]);
 150         buf += 2;
 151     }
 152 }
 153
 154 /* return -1 if error, 0 if OK */
 155 static int put_packet(GDBState *s, char *buf)
 156 {
 157     char buf1[3];
 158     int len, csum, ch, i;
 159
 160 #ifdef DEBUG_GDB
 161     printf("reply='%s'\n", buf);
 162 #endif
 163
 164     for(;;) {
 165         buf1[0] = '$';
 166         put_buffer(s, buf1, 1);
 167         len = strlen(buf);
 168         put_buffer(s, buf, len);
 169         csum = 0;
 170         for(i = 0; i < len; i++) {
 171             csum += buf[i];
 172         }
 173         buf1[0] = '#';
 174         buf1[1] = tohex((csum >> 4) & 0xf);
 175         buf1[2] = tohex((csum) & 0xf);
 176
 177         put_buffer(s, buf1, 3);
 178
 179         ch = get_char(s);
 180         if (ch < 0)
 181             return -1;
 182         if (ch == '+')
 183             break;
 184     }
 185     return 0;
 186 }
 187
 188 #if defined(TARGET_I386)
 189
 190 static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
 191 {
 192     uint32_t *registers = (uint32_t *)mem_buf;
 193     int i, fpus;
 194
 195     for(i = 0; i < 8; i++) {
 196         registers[i] = env->regs[i];
 197     }
 198     registers[8] = env->eip;
 199     registers[9] = env->eflags;
 200     registers[10] = env->segs[R_CS].selector;
 201     registers[11] = env->segs[R_SS].selector;
 202     registers[12] = env->segs[R_DS].selector;
 203     registers[13] = env->segs[R_ES].selector;
 204     registers[14] = env->segs[R_FS].selector;
 205     registers[15] = env->segs[R_GS].selector;
 206     /* XXX: convert floats */
 207     for(i = 0; i < 8; i++) {
 208         memcpy(mem_buf + 16 * 4 + i * 10, &env->fpregs[i], 10);
 209     }
 210     registers[36] = env->fpuc;
 211     fpus = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
 212     registers[37] = fpus;
 213     registers[38] = 0; /* XXX: convert tags */
 214     registers[39] = 0; /* fiseg */
 215     registers[40] = 0; /* fioff */
 216     registers[41] = 0; /* foseg */
 217     registers[42] = 0; /* fooff */
 218     registers[43] = 0; /* fop */
 219
 220     for(i = 0; i < 16; i++)
 221         tswapls(&registers[i]);
 222     for(i = 36; i < 44; i++)
 223         tswapls(&registers[i]);
 224     return 44 * 4;
 225 }
 226
 227 static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
 228 {
 229     uint32_t *registers = (uint32_t *)mem_buf;
 230     int i;
 231
 232     for(i = 0; i < 8; i++) {
 233         env->regs[i] = tswapl(registers[i]);
 234     }
 235     env->eip = tswapl(registers[8]);
 236     env->eflags = tswapl(registers[9]);
 237 #if defined(CONFIG_USER_ONLY)
 238 #define LOAD_SEG(index, sreg)\
 239             if (tswapl(registers[index]) != env->segs[sreg].selector)\
 240                 cpu_x86_load_seg(env, sreg, tswapl(registers[index]));
 241             LOAD_SEG(10, R_CS);
 242             LOAD_SEG(11, R_SS);
 243             LOAD_SEG(12, R_DS);
 244             LOAD_SEG(13, R_ES);
 245             LOAD_SEG(14, R_FS);
 246             LOAD_SEG(15, R_GS);
 247 #endif
 248 }
 249
 250 #elif defined (TARGET_PPC)
 251 static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
 252 {
 253     uint32_t *registers = (uint32_t *)mem_buf, tmp;
 254     int i;
 255
 256     /* fill in gprs */
 257     for(i = 0; i < 32; i++) {
 258         registers[i] = tswapl(env->gpr[i]);
 259     }
 260     /* fill in fprs */
 261     for (i = 0; i < 32; i++) {
 262         registers[(i * 2) + 32] = tswapl(*((uint32_t *)&env->fpr[i]));
 263         registers[(i * 2) + 33] = tswapl(*((uint32_t *)&env->fpr[i] + 1));
 264     }
 265     /* nip, msr, ccr, lnk, ctr, xer, mq */
 266     registers[96] = tswapl(env->nip);
 267     registers[97] = tswapl(do_load_msr(env));
 268     tmp = 0;
 269     for (i = 0; i < 8; i++)
 270         tmp |= env->crf[i] << (32 - ((i + 1) * 4));
 271     registers[98] = tswapl(tmp);
 272     registers[99] = tswapl(env->lr);
 273     registers[100] = tswapl(env->ctr);
 274     registers[101] = tswapl(do_load_xer(env));
 275     registers[102] = 0;
 276
 277     return 103 * 4;
 278 }
 279
 280 static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
 281 {
 282     uint32_t *registers = (uint32_t *)mem_buf;
 283     int i;
 284
 285     /* fill in gprs */
 286     for (i = 0; i < 32; i++) {
 287         env->gpr[i] = tswapl(registers[i]);
 288     }
 289     /* fill in fprs */
 290     for (i = 0; i < 32; i++) {
 291         *((uint32_t *)&env->fpr[i]) = tswapl(registers[(i * 2) + 32]);
 292         *((uint32_t *)&env->fpr[i] + 1) = tswapl(registers[(i * 2) + 33]);
 293     }
 294     /* nip, msr, ccr, lnk, ctr, xer, mq */
 295     env->nip = tswapl(registers[96]);
 296     do_store_msr(env, tswapl(registers[97]));
 297     registers[98] = tswapl(registers[98]);
 298     for (i = 0; i < 8; i++)
 299         env->crf[i] = (registers[98] >> (32 - ((i + 1) * 4))) & 0xF;
 300     env->lr = tswapl(registers[99]);
 301     env->ctr = tswapl(registers[100]);
 302     do_store_xer(env, tswapl(registers[101]));
 303 }
 304 #elif defined (TARGET_SPARC)
 305 static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
 306 {
 307     target_ulong *registers = (target_ulong *)mem_buf;
 308     int i;
 309
 310     /* fill in g0..g7 */
 311     for(i = 0; i < 8; i++) {
 312         registers[i] = tswapl(env->gregs[i]);
 313     }
 314     /* fill in register window */
 315     for(i = 0; i < 24; i++) {
 316         registers[i + 8] = tswapl(env->regwptr[i]);
 317     }
 318     /* fill in fprs */
 319     for (i = 0; i < 32; i++) {
 320         registers[i + 32] = tswapl(*((uint32_t *)&env->fpr[i]));
 321     }
 322 #ifndef TARGET_SPARC64
 323     /* Y, PSR, WIM, TBR, PC, NPC, FPSR, CPSR */
 324     registers[64] = tswapl(env->y);
 325     {
 326         target_ulong tmp;
 327
 328         tmp = GET_PSR(env);
 329         registers[65] = tswapl(tmp);
 330     }
 331     registers[66] = tswapl(env->wim);
 332     registers[67] = tswapl(env->tbr);
 333     registers[68] = tswapl(env->pc);
 334     registers[69] = tswapl(env->npc);
 335     registers[70] = tswapl(env->fsr);
 336     registers[71] = 0; /* csr */
 337     registers[72] = 0;
 338     return 73 * sizeof(target_ulong);
 339 #else
 340     for (i = 0; i < 32; i += 2) {
 341         registers[i/2 + 64] = tswapl(*((uint64_t *)&env->fpr[i]));
 342     }
 343     registers[81] = tswapl(env->pc);
 344     registers[82] = tswapl(env->npc);
 345     registers[83] = tswapl(env->tstate[env->tl]);
 346     registers[84] = tswapl(env->fsr);
 347     registers[85] = tswapl(env->fprs);
 348     registers[86] = tswapl(env->y);
 349     return 87 * sizeof(target_ulong);
 350 #endif
 351 }
 352
 353 static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
 354 {
 355     target_ulong *registers = (target_ulong *)mem_buf;
 356     int i;
 357
 358     /* fill in g0..g7 */
 359     for(i = 0; i < 7; i++) {
 360         env->gregs[i] = tswapl(registers[i]);
 361     }
 362     /* fill in register window */
 363     for(i = 0; i < 24; i++) {
 364         env->regwptr[i] = tswapl(registers[i + 8]);
 365     }
 366     /* fill in fprs */
 367     for (i = 0; i < 32; i++) {
 368         *((uint32_t *)&env->fpr[i]) = tswapl(registers[i + 32]);
 369     }
 370 #ifndef TARGET_SPARC64
 371     /* Y, PSR, WIM, TBR, PC, NPC, FPSR, CPSR */
 372     env->y = tswapl(registers[64]);
 373     PUT_PSR(env, tswapl(registers[65]));
 374     env->wim = tswapl(registers[66]);
 375     env->tbr = tswapl(registers[67]);
 376     env->pc = tswapl(registers[68]);
 377     env->npc = tswapl(registers[69]);
 378     env->fsr = tswapl(registers[70]);
 379 #else
 380     for (i = 0; i < 32; i += 2) {
 381         uint64_t tmp;
 382         tmp = tswapl(registers[i/2 + 64]) << 32;
 383         tmp |= tswapl(registers[i/2 + 64 + 1]);
 384         *((uint64_t *)&env->fpr[i]) = tmp;
 385     }
 386     env->pc = tswapl(registers[81]);
 387     env->npc = tswapl(registers[82]);
 388     env->tstate[env->tl] = tswapl(registers[83]);
 389     env->fsr = tswapl(registers[84]);
 390     env->fprs = tswapl(registers[85]);
 391     env->y = tswapl(registers[86]);
 392 #endif
 393 }
 394 #elif defined (TARGET_ARM)
 395 static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
 396 {
 397     int i;
 398     uint8_t *ptr;
 399
 400     ptr = mem_buf;
 401     /* 16 core integer registers (4 bytes each).  */
 402     for (i = 0; i < 16; i++)
 403       {
 404         *(uint32_t *)ptr = tswapl(env->regs[i]);
 405         ptr += 4;
 406       }
 407     /* 8 FPA registers (12 bytes each), FPS (4 bytes).
 408        Not yet implemented.  */
 409     memset (ptr, 0, 8 * 12 + 4);
 410     ptr += 8 * 12 + 4;
 411     /* CPSR (4 bytes).  */
 412     *(uint32_t *)ptr = tswapl (cpsr_read(env));
 413     ptr += 4;
 414
 415     return ptr - mem_buf;
 416 }
 417
 418 static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
 419 {
 420     int i;
 421     uint8_t *ptr;
 422
 423     ptr = mem_buf;
 424     /* Core integer registers.  */
 425     for (i = 0; i < 16; i++)
 426       {
 427         env->regs[i] = tswapl(*(uint32_t *)ptr);
 428         ptr += 4;
 429       }
 430     /* Ignore FPA regs and scr.  */
 431     ptr += 8 * 12 + 4;
 432     cpsr_write (env, tswapl(*(uint32_t *)ptr), 0xffffffff);
 433 }
 434 #elif defined (TARGET_MIPS)
 435 static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
 436 {
 437     int i;
 438     uint8_t *ptr;
 439
 440     ptr = mem_buf;
 441     for (i = 0; i < 32; i++)
 442       {
 443         *(uint32_t *)ptr = tswapl(env->gpr[i]);
 444         ptr += 4;
 445       }
 446
 447     *(uint32_t *)ptr = tswapl(env->CP0_Status);
 448     ptr += 4;
 449
 450     *(uint32_t *)ptr = tswapl(env->LO);
 451     ptr += 4;
 452
 453     *(uint32_t *)ptr = tswapl(env->HI);
 454     ptr += 4;
 455
 456     *(uint32_t *)ptr = tswapl(env->CP0_BadVAddr);
 457     ptr += 4;
 458
 459     *(uint32_t *)ptr = tswapl(env->CP0_Cause);
 460     ptr += 4;
 461
 462     *(uint32_t *)ptr = tswapl(env->PC);
 463     ptr += 4;
 464
 465     /* 32 FP registers, fsr, fir, fp.  Not yet implemented.  */
 466
 467     return ptr - mem_buf;
 468 }
 469
 470 static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
 471 {
 472     int i;
 473     uint8_t *ptr;
 474
 475     ptr = mem_buf;
 476     for (i = 0; i < 32; i++)
 477       {
 478         env->gpr[i] = tswapl(*(uint32_t *)ptr);
 479         ptr += 4;
 480       }
 481
 482     env->CP0_Status = tswapl(*(uint32_t *)ptr);
 483     ptr += 4;
 484
 485     env->LO = tswapl(*(uint32_t *)ptr);
 486     ptr += 4;
 487
 488     env->HI = tswapl(*(uint32_t *)ptr);
 489     ptr += 4;
 490
 491     env->CP0_BadVAddr = tswapl(*(uint32_t *)ptr);
 492     ptr += 4;
 493
 494     env->CP0_Cause = tswapl(*(uint32_t *)ptr);
 495     ptr += 4;
 496
 497     env->PC = tswapl(*(uint32_t *)ptr);
 498     ptr += 4;
 499 }
 500 #elif defined (TARGET_SH4)
 501 static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
 502 {
 503   uint32_t *ptr = (uint32_t *)mem_buf;
 504   int i;
 505
 506 #define SAVE(x) *ptr++=tswapl(x)
 507   for (i = 0; i < 16; i++) SAVE(env->gregs[i]);
 508   SAVE (env->pc);
 509   SAVE (env->pr);
 510   SAVE (env->gbr);
 511   SAVE (env->vbr);
 512   SAVE (env->mach);
 513   SAVE (env->macl);
 514   SAVE (env->sr);
 515   SAVE (0); /* TICKS */
 516   SAVE (0); /* STALLS */
 517   SAVE (0); /* CYCLES */
 518   SAVE (0); /* INSTS */
 519   SAVE (0); /* PLR */
 520
 521   return ((uint8_t *)ptr - mem_buf);
 522 }
 523
 524 static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
 525 {
 526   uint32_t *ptr = (uint32_t *)mem_buf;
 527   int i;
 528
 529 #define LOAD(x) (x)=*ptr++;
 530   for (i = 0; i < 16; i++) LOAD(env->gregs[i]);
 531   LOAD (env->pc);
 532   LOAD (env->pr);
 533   LOAD (env->gbr);
 534   LOAD (env->vbr);
 535   LOAD (env->mach);
 536   LOAD (env->macl);
 537   LOAD (env->sr);
 538 }
 539 #else
 540 static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
 541 {
 542     return 0;
 543 }
 544
 545 static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
 546 {
 547 }
 548
 549 #endif
 550
 551 static int gdb_handle_packet(GDBState *s, CPUState *env, const char *line_buf)
 552 {
 553     const char *p;
 554     int ch, reg_size, type;
 555     char buf[4096];
 556     uint8_t mem_buf[2000];
 557     uint32_t *registers;
 558     uint32_t addr, len;
 559
 560 #ifdef DEBUG_GDB
 561     printf("command='%s'\n", line_buf);
 562 #endif
 563     p = line_buf;
 564     ch = *p++;
 565     switch(ch) {
 566     case '?':
 567         /* TODO: Make this return the correct value for user-mode.  */
 568         snprintf(buf, sizeof(buf), "S%02x", SIGTRAP);
 569         put_packet(s, buf);
 570         break;
 571     case 'c':
 572         if (*p != '\0') {
 573             addr = strtoul(p, (char **)&p, 16);
 574 #if defined(TARGET_I386)
 575             env->eip = addr;
 576 #elif defined (TARGET_PPC)
 577             env->nip = addr;
 578 #elif defined (TARGET_SPARC)
 579             env->pc = addr;
 580             env->npc = addr + 4;
 581 #elif defined (TARGET_ARM)
 582             env->regs[15] = addr;
 583 #elif defined (TARGET_SH4)
 584             env->pc = addr;
 585 #endif
 586         }
 587 #ifdef CONFIG_USER_ONLY
 588         s->running_state = 1;
 589 #else
 590         vm_start();
 591 #endif
 592         return RS_IDLE;
 593     case 's':
 594         if (*p != '\0') {
 595             addr = strtoul(p, (char **)&p, 16);
 596 #if defined(TARGET_I386)
 597             env->eip = addr;
 598 #elif defined (TARGET_PPC)
 599             env->nip = addr;
 600 #elif defined (TARGET_SPARC)
 601             env->pc = addr;
 602             env->npc = addr + 4;
 603 #elif defined (TARGET_ARM)
 604             env->regs[15] = addr;
 605 #elif defined (TARGET_SH4)
 606             env->pc = addr;
 607 #endif
 608         }
 609         cpu_single_step(env, 1);
 610 #ifdef CONFIG_USER_ONLY
 611         s->running_state = 1;
 612 #else
 613         vm_start();
 614 #endif
 615         return RS_IDLE;
 616     case 'g':
 617         reg_size = cpu_gdb_read_registers(env, mem_buf);
 618         memtohex(buf, mem_buf, reg_size);
 619         put_packet(s, buf);
 620         break;
 621     case 'G':
 622         registers = (void *)mem_buf;
 623         len = strlen(p) / 2;
 624         hextomem((uint8_t *)registers, p, len);
 625         cpu_gdb_write_registers(env, mem_buf, len);
 626         put_packet(s, "OK");
 627         break;
 628     case 'm':
 629         addr = strtoul(p, (char **)&p, 16);
 630         if (*p == ',')
 631             p++;
 632         len = strtoul(p, NULL, 16);
 633         if (cpu_memory_rw_debug(env, addr, mem_buf, len, 0) != 0) {
 634             put_packet (s, "E14");
 635         } else {
 636             memtohex(buf, mem_buf, len);
 637             put_packet(s, buf);
 638         }
 639         break;
 640     case 'M':
 641         addr = strtoul(p, (char **)&p, 16);
 642         if (*p == ',')
 643             p++;
 644         len = strtoul(p, (char **)&p, 16);
 645         if (*p == ':')
 646             p++;
 647         hextomem(mem_buf, p, len);
 648         if (cpu_memory_rw_debug(env, addr, mem_buf, len, 1) != 0)
 649             put_packet(s, "E14");
 650         else
 651             put_packet(s, "OK");
 652         break;
 653     case 'Z':
 654         type = strtoul(p, (char **)&p, 16);
 655         if (*p == ',')
 656             p++;
 657         addr = strtoul(p, (char **)&p, 16);
 658         if (*p == ',')
 659             p++;
 660         len = strtoul(p, (char **)&p, 16);
 661         if (type == 0 || type == 1) {
 662             if (cpu_breakpoint_insert(env, addr) < 0)
 663                 goto breakpoint_error;
 664             put_packet(s, "OK");
 665         } else {
 666         breakpoint_error:
 667             put_packet(s, "E22");
 668         }
 669         break;
 670     case 'z':
 671         type = strtoul(p, (char **)&p, 16);
 672         if (*p == ',')
 673             p++;
 674         addr = strtoul(p, (char **)&p, 16);
 675         if (*p == ',')
 676             p++;
 677         len = strtoul(p, (char **)&p, 16);
 678         if (type == 0 || type == 1) {
 679             cpu_breakpoint_remove(env, addr);
 680             put_packet(s, "OK");
 681         } else {
 682             goto breakpoint_error;
 683         }
 684         break;
 685 #ifdef CONFIG_USER_ONLY
 686     case 'q':
 687         if (strncmp(p, "Offsets", 7) == 0) {
 688             TaskState *ts = env->opaque;
 689
 690             sprintf(buf, "Text=%x;Data=%x;Bss=%x", ts->info->code_offset,
 691                 ts->info->data_offset, ts->info->data_offset);
 692             put_packet(s, buf);
 693             break;
 694         }
 695         /* Fall through.  */
 696 #endif
 697     default:
 698         //        unknown_command:
 699         /* put empty packet */
 700         buf[0] = '\0';
 701         put_packet(s, buf);
 702         break;
 703     }
 704     return RS_IDLE;
 705 }
 706
 707 extern void tb_flush(CPUState *env);
 708
 709 #ifndef CONFIG_USER_ONLY
 710 static void gdb_vm_stopped(void *opaque, int reason)
 711 {
 712     GDBState *s = opaque;
 713     char buf[256];
 714     int ret;
 715
 716     /* disable single step if it was enable */
 717     cpu_single_step(s->env, 0);
 718
 719     if (reason == EXCP_DEBUG) {
 720         tb_flush(s->env);
 721         ret = SIGTRAP;
 722     } else if (reason == EXCP_INTERRUPT) {
 723         ret = SIGINT;
 724     } else {
 725         ret = 0;
 726     }
 727     snprintf(buf, sizeof(buf), "S%02x", ret);
 728     put_packet(s, buf);
 729 }
 730 #endif
 731
 732 static void gdb_read_byte(GDBState *s, int ch)
 733 {
 734     CPUState *env = s->env;
 735     int i, csum;
 736     char reply[1];
 737
 738 #ifndef CONFIG_USER_ONLY
 739     if (vm_running) {
 740         /* when the CPU is running, we cannot do anything except stop
 741            it when receiving a char */
 742         vm_stop(EXCP_INTERRUPT);
 743     } else
 744 #endif
 745     {
 746         switch(s->state) {
 747         case RS_IDLE:
 748             if (ch == '$') {
 749                 s->line_buf_index = 0;
 750                 s->state = RS_GETLINE;
 751             }
 752             break;
 753         case RS_GETLINE:
 754             if (ch == '#') {
 755             s->state = RS_CHKSUM1;
 756             } else if (s->line_buf_index >= sizeof(s->line_buf) - 1) {
 757                 s->state = RS_IDLE;
 758             } else {
 759             s->line_buf[s->line_buf_index++] = ch;
 760             }
 761             break;
 762         case RS_CHKSUM1:
 763             s->line_buf[s->line_buf_index] = '\0';
 764             s->line_csum = fromhex(ch) << 4;
 765             s->state = RS_CHKSUM2;
 766             break;
 767         case RS_CHKSUM2:
 768             s->line_csum |= fromhex(ch);
 769             csum = 0;
 770             for(i = 0; i < s->line_buf_index; i++) {
 771                 csum += s->line_buf[i];
 772             }
 773             if (s->line_csum != (csum & 0xff)) {
 774                 reply[0] = '-';
 775                 put_buffer(s, reply, 1);
 776                 s->state = RS_IDLE;
 777             } else {
 778                 reply[0] = '+';
 779                 put_buffer(s, reply, 1);
 780                 s->state = gdb_handle_packet(s, env, s->line_buf);
 781             }
 782             break;
 783         }
 784     }
 785 }
 786
 787 #ifdef CONFIG_USER_ONLY
 788 int
 789 gdb_handlesig (CPUState *env, int sig)
 790 {
 791   GDBState *s;
 792   char buf[256];
 793   int n;
 794
 795   if (gdbserver_fd < 0)
 796     return sig;
 797
 798   s = &gdbserver_state;
 799
 800   /* disable single step if it was enabled */
 801   cpu_single_step(env, 0);
 802   tb_flush(env);
 803
 804   if (sig != 0)
 805     {
 806       snprintf(buf, sizeof(buf), "S%02x", sig);
 807       put_packet(s, buf);
 808     }
 809
 810   sig = 0;
 811   s->state = RS_IDLE;
 812   s->running_state = 0;
 813   while (s->running_state == 0) {
 814       n = read (s->fd, buf, 256);
 815       if (n > 0)
 816         {
 817           int i;
 818
 819           for (i = 0; i < n; i++)
 820             gdb_read_byte (s, buf[i]);
 821         }
 822       else if (n == 0 || errno != EAGAIN)
 823         {
 824           /* XXX: Connection closed.  Should probably wait for annother
 825              connection before continuing.  */
 826           return sig;
 827         }
 828   }
 829   return sig;
 830 }
 831
 832 /* Tell the remote gdb that the process has exited.  */
 833 void gdb_exit(CPUState *env, int code)
 834 {
 835   GDBState *s;
 836   char buf[4];
 837
 838   if (gdbserver_fd < 0)
 839     return;
 840
 841   s = &gdbserver_state;
 842
 843   snprintf(buf, sizeof(buf), "W%02x", code);
 844   put_packet(s, buf);
 845 }
 846
 847 #else
 848 static void gdb_read(void *opaque)
 849 {
 850     GDBState *s = opaque;
 851     int i, size;
 852     uint8_t buf[4096];
 853
 854     size = recv(s->fd, buf, sizeof(buf), 0);
 855     if (size < 0)
 856         return;
 857     if (size == 0) {
 858         /* end of connection */
 859         qemu_del_vm_stop_handler(gdb_vm_stopped, s);
 860         qemu_set_fd_handler(s->fd, NULL, NULL, NULL);
 861         qemu_free(s);
 862         vm_start();
 863     } else {
 864         for(i = 0; i < size; i++)
 865             gdb_read_byte(s, buf[i]);
 866     }
 867 }
 868
 869 #endif
 870
 871 static void gdb_accept(void *opaque)
 872 {
 873     GDBState *s;
 874     struct sockaddr_in sockaddr;
 875     socklen_t len;
 876     int val, fd;
 877
 878     for(;;) {
 879         len = sizeof(sockaddr);
 880         fd = accept(gdbserver_fd, (struct sockaddr *)&sockaddr, &len);
 881         if (fd < 0 && errno != EINTR) {
 882             perror("accept");
 883             return;
 884         } else if (fd >= 0) {
 885             break;
 886         }
 887     }
 888
 889     /* set short latency */
 890     val = 1;
 891     setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, (char *)&val, sizeof(val));
 892
 893 #ifdef CONFIG_USER_ONLY
 894     s = &gdbserver_state;
 895     memset (s, 0, sizeof (GDBState));
 896 #else
 897     s = qemu_mallocz(sizeof(GDBState));
 898     if (!s) {
 899         close(fd);
 900         return;
 901     }
 902 #endif
 903     s->env = first_cpu; /* XXX: allow to change CPU */
 904     s->fd = fd;
 905
 906 #ifdef CONFIG_USER_ONLY
 907     fcntl(fd, F_SETFL, O_NONBLOCK);
 908 #else
 909     socket_set_nonblock(fd);
 910
 911     /* stop the VM */
 912     vm_stop(EXCP_INTERRUPT);
 913
 914     /* start handling I/O */
 915     qemu_set_fd_handler(s->fd, gdb_read, NULL, s);
 916     /* when the VM is stopped, the following callback is called */
 917     qemu_add_vm_stop_handler(gdb_vm_stopped, s);
 918 #endif
 919 }
 920
 921 static int gdbserver_open(int port)
 922 {
 923     struct sockaddr_in sockaddr;
 924     int fd, val, ret;
 925
 926     fd = socket(PF_INET, SOCK_STREAM, 0);
 927     if (fd < 0) {
 928         perror("socket");
 929         return -1;
 930     }
 931
 932     /* allow fast reuse */
 933     val = 1;
 934     setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *)&val, sizeof(val));
 935
 936     sockaddr.sin_family = AF_INET;
 937     sockaddr.sin_port = htons(port);
 938     sockaddr.sin_addr.s_addr = 0;
 939     ret = bind(fd, (struct sockaddr *)&sockaddr, sizeof(sockaddr));
 940     if (ret < 0) {
 941         perror("bind");
 942         return -1;
 943     }
 944     ret = listen(fd, 0);
 945     if (ret < 0) {
 946         perror("listen");
 947         return -1;
 948     }
 949 #ifndef CONFIG_USER_ONLY
 950     socket_set_nonblock(fd);
 951 #endif
 952     return fd;
 953 }
 954
 955 int gdbserver_start(int port)
 956 {
 957     gdbserver_fd = gdbserver_open(port);
 958     if (gdbserver_fd < 0)
 959         return -1;
 960     /* accept connections */
 961 #ifdef CONFIG_USER_ONLY
 962     gdb_accept (NULL);
 963 #else
 964     qemu_set_fd_handler(gdbserver_fd, gdb_accept, NULL, NULL);
 965 #endif
 966     return 0;
 967 }