Blame view

gdbstub.c 16.4 KB
bellard authored
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
/*
 * gdb server stub
 * 
 * Copyright (c) 2003 Fabrice Bellard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
20
21
#include "vl.h"
bellard authored
22
23
24
25
26
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <signal.h>
bellard authored
27
//#define DEBUG_GDB
bellard authored
28
29
30
31
32
33
34
enum RSState {
    RS_IDLE,
    RS_GETLINE,
    RS_CHKSUM1,
    RS_CHKSUM2,
};
bellard authored
35
36
static int gdbserver_fd;
bellard authored
37
38
39
40
41
42
43
44
typedef struct GDBState {
    enum RSState state;
    int fd;
    char line_buf[4096];
    int line_buf_index;
    int line_csum;
} GDBState;
bellard authored
45
46
static int get_char(GDBState *s)
bellard authored
47
48
49
50
51
{
    uint8_t ch;
    int ret;

    for(;;) {
52
        ret = read(s->fd, &ch, 1);
bellard authored
53
54
55
56
57
58
59
60
61
62
63
64
        if (ret < 0) {
            if (errno != EINTR && errno != EAGAIN)
                return -1;
        } else if (ret == 0) {
            return -1;
        } else {
            break;
        }
    }
    return ch;
}
65
static void put_buffer(GDBState *s, const uint8_t *buf, int len)
bellard authored
66
67
68
69
{
    int ret;

    while (len > 0) {
70
        ret = write(s->fd, buf, len);
bellard authored
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
        if (ret < 0) {
            if (errno != EINTR && errno != EAGAIN)
                return;
        } else {
            buf += ret;
            len -= ret;
        }
    }
}

static inline int fromhex(int v)
{
    if (v >= '0' && v <= '9')
        return v - '0';
    else if (v >= 'A' && v <= 'F')
        return v - 'A' + 10;
    else if (v >= 'a' && v <= 'f')
        return v - 'a' + 10;
    else
        return 0;
}

static inline int tohex(int v)
{
    if (v < 10)
        return v + '0';
    else
        return v - 10 + 'a';
}

static void memtohex(char *buf, const uint8_t *mem, int len)
{
    int i, c;
    char *q;
    q = buf;
    for(i = 0; i < len; i++) {
        c = mem[i];
        *q++ = tohex(c >> 4);
        *q++ = tohex(c & 0xf);
    }
    *q = '\0';
}

static void hextomem(uint8_t *mem, const char *buf, int len)
{
    int i;

    for(i = 0; i < len; i++) {
        mem[i] = (fromhex(buf[0]) << 4) | fromhex(buf[1]);
        buf += 2;
    }
}

/* return -1 if error, 0 if OK */
125
static int put_packet(GDBState *s, char *buf)
bellard authored
126
127
128
129
130
131
132
133
134
135
{
    char buf1[3];
    int len, csum, ch, i;

#ifdef DEBUG_GDB
    printf("reply='%s'\n", buf);
#endif

    for(;;) {
        buf1[0] = '$';
136
        put_buffer(s, buf1, 1);
bellard authored
137
        len = strlen(buf);
138
        put_buffer(s, buf, len);
bellard authored
139
140
141
142
143
144
145
146
        csum = 0;
        for(i = 0; i < len; i++) {
            csum += buf[i];
        }
        buf1[0] = '#';
        buf1[1] = tohex((csum >> 4) & 0xf);
        buf1[2] = tohex((csum) & 0xf);
147
        put_buffer(s, buf1, 3);
bellard authored
148
149
        ch = get_char(s);
bellard authored
150
151
152
153
154
155
156
157
        if (ch < 0)
            return -1;
        if (ch == '+')
            break;
    }
    return 0;
}
bellard authored
158
159
160
161
#if defined(TARGET_I386)

static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
{
162
    uint32_t *registers = (uint32_t *)mem_buf;
bellard authored
163
164
165
    int i, fpus;

    for(i = 0; i < 8; i++) {
166
        registers[i] = env->regs[i];
bellard authored
167
    }
168
169
170
171
172
173
174
175
    registers[8] = env->eip;
    registers[9] = env->eflags;
    registers[10] = env->segs[R_CS].selector;
    registers[11] = env->segs[R_SS].selector;
    registers[12] = env->segs[R_DS].selector;
    registers[13] = env->segs[R_ES].selector;
    registers[14] = env->segs[R_FS].selector;
    registers[15] = env->segs[R_GS].selector;
bellard authored
176
177
178
179
    /* XXX: convert floats */
    for(i = 0; i < 8; i++) {
        memcpy(mem_buf + 16 * 4 + i * 10, &env->fpregs[i], 10);
    }
180
    registers[36] = env->fpuc;
bellard authored
181
    fpus = (env->fpus & ~0x3800) | (env->fpstt & 0x7) << 11;
182
183
184
185
186
187
188
189
190
191
192
193
    registers[37] = fpus;
    registers[38] = 0; /* XXX: convert tags */
    registers[39] = 0; /* fiseg */
    registers[40] = 0; /* fioff */
    registers[41] = 0; /* foseg */
    registers[42] = 0; /* fooff */
    registers[43] = 0; /* fop */

    for(i = 0; i < 16; i++)
        tswapls(&registers[i]);
    for(i = 36; i < 44; i++)
        tswapls(&registers[i]);
bellard authored
194
195
196
197
198
199
200
201
202
203
204
    return 44 * 4;
}

static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
{
    uint32_t *registers = (uint32_t *)mem_buf;
    int i;

    for(i = 0; i < 8; i++) {
        env->regs[i] = tswapl(registers[i]);
    }
205
206
    env->eip = tswapl(registers[8]);
    env->eflags = tswapl(registers[9]);
bellard authored
207
208
209
210
211
212
213
214
215
216
217
218
219
#if defined(CONFIG_USER_ONLY)
#define LOAD_SEG(index, sreg)\
            if (tswapl(registers[index]) != env->segs[sreg].selector)\
                cpu_x86_load_seg(env, sreg, tswapl(registers[index]));
            LOAD_SEG(10, R_CS);
            LOAD_SEG(11, R_SS);
            LOAD_SEG(12, R_DS);
            LOAD_SEG(13, R_ES);
            LOAD_SEG(14, R_FS);
            LOAD_SEG(15, R_GS);
#endif
}
bellard authored
220
#elif defined (TARGET_PPC)
221
222
223
224
225
226
227
static uint32_t from_le32 (uint32_t *buf)
{
    uint8_t *p = (uint8_t *)buf;

    return p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
}
bellard authored
228
229
static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
{
230
    uint32_t *registers = (uint32_t *)mem_buf, tmp;
bellard authored
231
232
233
    int i;

    /* fill in gprs */
234
    for(i = 0; i < 32; i++) {
235
        registers[i] = tswapl(env->gpr[i]);
bellard authored
236
237
238
    }
    /* fill in fprs */
    for (i = 0; i < 32; i++) {
239
240
        registers[(i * 2) + 32] = tswapl(*((uint32_t *)&env->fpr[i]));
	registers[(i * 2) + 33] = tswapl(*((uint32_t *)&env->fpr[i] + 1));
bellard authored
241
242
    }
    /* nip, msr, ccr, lnk, ctr, xer, mq */
243
244
    registers[96] = tswapl(env->nip);
    registers[97] = tswapl(_load_msr(env));
bellard authored
245
246
    tmp = 0;
    for (i = 0; i < 8; i++)
247
        tmp |= env->crf[i] << (32 - ((i + 1) * 4));
248
249
250
251
252
    registers[98] = tswapl(tmp);
    registers[99] = tswapl(env->lr);
    registers[100] = tswapl(env->ctr);
    registers[101] = tswapl(_load_xer(env));
    registers[102] = 0;
253
254

    return 103 * 4;
bellard authored
255
256
257
258
259
260
261
262
263
}

static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
{
    uint32_t *registers = (uint32_t *)mem_buf;
    int i;

    /* fill in gprs */
    for (i = 0; i < 32; i++) {
264
        env->gpr[i] = tswapl(registers[i]);
bellard authored
265
266
267
    }
    /* fill in fprs */
    for (i = 0; i < 32; i++) {
268
269
        *((uint32_t *)&env->fpr[i]) = tswapl(registers[(i * 2) + 32]);
	*((uint32_t *)&env->fpr[i] + 1) = tswapl(registers[(i * 2) + 33]);
bellard authored
270
271
    }
    /* nip, msr, ccr, lnk, ctr, xer, mq */
272
273
274
    env->nip = tswapl(registers[96]);
    _store_msr(env, tswapl(registers[97]));
    registers[98] = tswapl(registers[98]);
bellard authored
275
    for (i = 0; i < 8; i++)
276
        env->crf[i] = (registers[98] >> (32 - ((i + 1) * 4))) & 0xF;
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
    env->lr = tswapl(registers[99]);
    env->ctr = tswapl(registers[100]);
    _store_xer(env, tswapl(registers[101]));
}
#elif defined (TARGET_SPARC)
static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
{
    uint32_t *registers = (uint32_t *)mem_buf, tmp;
    int i;

    /* fill in g0..g7 */
    for(i = 0; i < 7; i++) {
        registers[i] = tswapl(env->gregs[i]);
    }
    /* fill in register window */
    for(i = 0; i < 24; i++) {
        registers[i + 8] = tswapl(env->regwptr[i]);
    }
    /* fill in fprs */
    for (i = 0; i < 32; i++) {
        registers[i + 32] = tswapl(*((uint32_t *)&env->fpr[i]));
    }
    /* Y, PSR, WIM, TBR, PC, NPC, FPSR, CPSR */
    registers[64] = tswapl(env->y);
    tmp = (0<<28) | (4<<24) | env->psr		\
	| (env->psrs? PSR_S : 0)		\
	| (env->psrs? PSR_PS : 0)		\
	| (env->psret? PSR_ET : 0)		\
	| env->cwp;
    registers[65] = tswapl(tmp);
    registers[66] = tswapl(env->wim);
    registers[67] = tswapl(env->tbr);
    registers[68] = tswapl(env->pc);
    registers[69] = tswapl(env->npc);
    registers[70] = tswapl(env->fsr);
    registers[71] = 0; /* csr */
    registers[72] = 0;

    return 73 * 4;
}

static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
{
    uint32_t *registers = (uint32_t *)mem_buf, tmp;
    int i;

    /* fill in g0..g7 */
    for(i = 0; i < 7; i++) {
        env->gregs[i] = tswapl(registers[i]);
    }
    /* fill in register window */
    for(i = 0; i < 24; i++) {
        env->regwptr[i] = tswapl(registers[i]);
    }
    /* fill in fprs */
    for (i = 0; i < 32; i++) {
        *((uint32_t *)&env->fpr[i]) = tswapl(registers[i + 32]);
    }
    /* Y, PSR, WIM, TBR, PC, NPC, FPSR, CPSR */
    env->y = tswapl(registers[64]);
    tmp = tswapl(registers[65]);
    env->psr = tmp & ~PSR_ICC;
    env->psrs = (tmp & PSR_S)? 1 : 0;
    env->psrps = (tmp & PSR_PS)? 1 : 0;
    env->psret = (tmp & PSR_ET)? 1 : 0;
    env->cwp = (tmp & PSR_CWP);
    env->wim = tswapl(registers[66]);
    env->tbr = tswapl(registers[67]);
    env->pc = tswapl(registers[68]);
    env->npc = tswapl(registers[69]);
    env->fsr = tswapl(registers[70]);
bellard authored
348
}
bellard authored
349
350
351
352
353
354
355
356
357
358
359
360
#else

static int cpu_gdb_read_registers(CPUState *env, uint8_t *mem_buf)
{
    return 0;
}

static void cpu_gdb_write_registers(CPUState *env, uint8_t *mem_buf, int size)
{
}

#endif
bellard authored
361
362

/* port = 0 means default port */
363
static int gdb_handle_packet(GDBState *s, const char *line_buf)
bellard authored
364
{
365
    CPUState *env = cpu_single_env;
bellard authored
366
    const char *p;
367
    int ch, reg_size, type;
bellard authored
368
369
370
371
372
    char buf[4096];
    uint8_t mem_buf[2000];
    uint32_t *registers;
    uint32_t addr, len;
373
374
375
376
377
378
379
380
381
382
383
384
385
#ifdef DEBUG_GDB
    printf("command='%s'\n", line_buf);
#endif
    p = line_buf;
    ch = *p++;
    switch(ch) {
    case '?':
        snprintf(buf, sizeof(buf), "S%02x", SIGTRAP);
        put_packet(s, buf);
        break;
    case 'c':
        if (*p != '\0') {
            addr = strtoul(p, (char **)&p, 16);
bellard authored
386
#if defined(TARGET_I386)
387
            env->eip = addr;
bellard authored
388
#elif defined (TARGET_PPC)
389
            env->nip = addr;
bellard authored
390
391
392
#elif defined (TARGET_SPARC)
            env->pc = addr;
            env->npc = addr + 4;
bellard authored
393
#endif
394
395
396
397
398
399
        }
        vm_start();
        break;
    case 's':
        if (*p != '\0') {
            addr = strtoul(p, (char **)&p, 16);
400
#if defined(TARGET_I386)
401
            env->eip = addr;
bellard authored
402
#elif defined (TARGET_PPC)
403
            env->nip = addr;
bellard authored
404
405
406
#elif defined (TARGET_SPARC)
            env->pc = addr;
            env->npc = addr + 4;
407
#endif
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
        }
        cpu_single_step(env, 1);
        vm_start();
        break;
    case 'g':
        reg_size = cpu_gdb_read_registers(env, mem_buf);
        memtohex(buf, mem_buf, reg_size);
        put_packet(s, buf);
        break;
    case 'G':
        registers = (void *)mem_buf;
        len = strlen(p) / 2;
        hextomem((uint8_t *)registers, p, len);
        cpu_gdb_write_registers(env, mem_buf, len);
        put_packet(s, "OK");
        break;
    case 'm':
        addr = strtoul(p, (char **)&p, 16);
        if (*p == ',')
            p++;
        len = strtoul(p, NULL, 16);
        if (cpu_memory_rw_debug(env, addr, mem_buf, len, 0) != 0)
            memset(mem_buf, 0, len);
        memtohex(buf, mem_buf, len);
        put_packet(s, buf);
        break;
    case 'M':
        addr = strtoul(p, (char **)&p, 16);
        if (*p == ',')
            p++;
        len = strtoul(p, (char **)&p, 16);
        if (*p == ',')
            p++;
        hextomem(mem_buf, p, len);
        if (cpu_memory_rw_debug(env, addr, mem_buf, len, 1) != 0)
            put_packet(s, "ENN");
        else
            put_packet(s, "OK");
        break;
    case 'Z':
        type = strtoul(p, (char **)&p, 16);
        if (*p == ',')
            p++;
        addr = strtoul(p, (char **)&p, 16);
        if (*p == ',')
            p++;
        len = strtoul(p, (char **)&p, 16);
        if (type == 0 || type == 1) {
            if (cpu_breakpoint_insert(env, addr) < 0)
                goto breakpoint_error;
            put_packet(s, "OK");
        } else {
        breakpoint_error:
            put_packet(s, "ENN");
        }
        break;
    case 'z':
        type = strtoul(p, (char **)&p, 16);
        if (*p == ',')
            p++;
        addr = strtoul(p, (char **)&p, 16);
        if (*p == ',')
            p++;
        len = strtoul(p, (char **)&p, 16);
        if (type == 0 || type == 1) {
            cpu_breakpoint_remove(env, addr);
            put_packet(s, "OK");
        } else {
            goto breakpoint_error;
        }
        break;
    default:
        //        unknown_command:
        /* put empty packet */
        buf[0] = '\0';
        put_packet(s, buf);
        break;
    }
    return RS_IDLE;
}

static void gdb_vm_stopped(void *opaque, int reason)
{
    GDBState *s = opaque;
    char buf[256];
    int ret;

    /* disable single step if it was enable */
    cpu_single_step(cpu_single_env, 0);

    if (reason == EXCP_DEBUG)
        ret = SIGTRAP;
    else
        ret = 0;
    snprintf(buf, sizeof(buf), "S%02x", ret);
    put_packet(s, buf);
}

static void gdb_read_byte(GDBState *s, int ch)
{
    int i, csum;
    char reply[1];

    if (vm_running) {
        /* when the CPU is running, we cannot do anything except stop
           it when receiving a char */
        vm_stop(EXCP_INTERRUPT);
    } else {
        switch(s->state) {
        case RS_IDLE:
            if (ch == '$') {
                s->line_buf_index = 0;
                s->state = RS_GETLINE;
521
            }
bellard authored
522
            break;
523
524
525
526
527
        case RS_GETLINE:
            if (ch == '#') {
            s->state = RS_CHKSUM1;
            } else if (s->line_buf_index >= sizeof(s->line_buf) - 1) {
                s->state = RS_IDLE;
bellard authored
528
            } else {
529
            s->line_buf[s->line_buf_index++] = ch;
bellard authored
530
531
            }
            break;
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
        case RS_CHKSUM1:
            s->line_buf[s->line_buf_index] = '\0';
            s->line_csum = fromhex(ch) << 4;
            s->state = RS_CHKSUM2;
            break;
        case RS_CHKSUM2:
            s->line_csum |= fromhex(ch);
            csum = 0;
            for(i = 0; i < s->line_buf_index; i++) {
                csum += s->line_buf[i];
            }
            if (s->line_csum != (csum & 0xff)) {
                reply[0] = '-';
                put_buffer(s, reply, 1);
                s->state = RS_IDLE;
bellard authored
547
            } else {
548
549
550
                reply[0] = '+';
                put_buffer(s, reply, 1);
                s->state = gdb_handle_packet(s, s->line_buf);
bellard authored
551
552
            }
            break;
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
        }
    }
}

static int gdb_can_read(void *opaque)
{
    return 256;
}

static void gdb_read(void *opaque, const uint8_t *buf, int size)
{
    GDBState *s = opaque;
    int i;
    if (size == 0) {
        /* end of connection */
        qemu_del_vm_stop_handler(gdb_vm_stopped, s);
        qemu_del_fd_read_handler(s->fd);
        qemu_free(s);
        vm_start();
    } else {
        for(i = 0; i < size; i++)
            gdb_read_byte(s, buf[i]);
    }
}

static void gdb_accept(void *opaque, const uint8_t *buf, int size)
{
    GDBState *s;
    struct sockaddr_in sockaddr;
    socklen_t len;
    int val, fd;

    for(;;) {
        len = sizeof(sockaddr);
        fd = accept(gdbserver_fd, (struct sockaddr *)&sockaddr, &len);
        if (fd < 0 && errno != EINTR) {
            perror("accept");
            return;
        } else if (fd >= 0) {
bellard authored
592
593
594
            break;
        }
    }
595
596
597

    /* set short latency */
    val = 1;
bellard authored
598
    setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val));
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656

    s = qemu_mallocz(sizeof(GDBState));
    if (!s) {
        close(fd);
        return;
    }
    s->fd = fd;

    fcntl(fd, F_SETFL, O_NONBLOCK);

    /* stop the VM */
    vm_stop(EXCP_INTERRUPT);

    /* start handling I/O */
    qemu_add_fd_read_handler(s->fd, gdb_can_read, gdb_read, s);
    /* when the VM is stopped, the following callback is called */
    qemu_add_vm_stop_handler(gdb_vm_stopped, s);
}

static int gdbserver_open(int port)
{
    struct sockaddr_in sockaddr;
    int fd, val, ret;

    fd = socket(PF_INET, SOCK_STREAM, 0);
    if (fd < 0) {
        perror("socket");
        return -1;
    }

    /* allow fast reuse */
    val = 1;
    setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));

    sockaddr.sin_family = AF_INET;
    sockaddr.sin_port = htons(port);
    sockaddr.sin_addr.s_addr = 0;
    ret = bind(fd, (struct sockaddr *)&sockaddr, sizeof(sockaddr));
    if (ret < 0) {
        perror("bind");
        return -1;
    }
    ret = listen(fd, 0);
    if (ret < 0) {
        perror("listen");
        return -1;
    }
    fcntl(fd, F_SETFL, O_NONBLOCK);
    return fd;
}

int gdbserver_start(int port)
{
    gdbserver_fd = gdbserver_open(port);
    if (gdbserver_fd < 0)
        return -1;
    /* accept connections */
    qemu_add_fd_read_handler(gdbserver_fd, NULL, gdb_accept, NULL);
bellard authored
657
658
    return 0;
}