gdb_main.c revision 133446
1131899Smarcel/* 2131899Smarcel * Copyright (c) 2004 Marcel Moolenaar 3131899Smarcel * All rights reserved. 4131899Smarcel * 5131899Smarcel * Redistribution and use in source and binary forms, with or without 6131899Smarcel * modification, are permitted provided that the following conditions 7131899Smarcel * are met: 8131899Smarcel * 9131899Smarcel * 1. Redistributions of source code must retain the above copyright 10131899Smarcel * notice, this list of conditions and the following disclaimer. 11131899Smarcel * 2. Redistributions in binary form must reproduce the above copyright 12131899Smarcel * notice, this list of conditions and the following disclaimer in the 13131899Smarcel * documentation and/or other materials provided with the distribution. 14131899Smarcel * 15131899Smarcel * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR 16131899Smarcel * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17131899Smarcel * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18131899Smarcel * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, 19131899Smarcel * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20131899Smarcel * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21131899Smarcel * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22131899Smarcel * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23131899Smarcel * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24131899Smarcel * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25131899Smarcel */ 26131899Smarcel 27131899Smarcel#include <sys/cdefs.h> 28131899Smarcel__FBSDID("$FreeBSD: head/sys/gdb/gdb_main.c 133446 2004-08-10 19:32:33Z marcel $"); 29131899Smarcel 30131899Smarcel#include <sys/param.h> 31131899Smarcel#include <sys/systm.h> 32131899Smarcel#include <sys/kdb.h> 33131899Smarcel#include <sys/kernel.h> 34131899Smarcel#include <sys/pcpu.h> 35131899Smarcel#include <sys/proc.h> 36131899Smarcel#include <sys/reboot.h> 37131899Smarcel 38131899Smarcel#include <machine/gdb_machdep.h> 39131899Smarcel#include <machine/kdb.h> 40131899Smarcel 41131899Smarcel#include <gdb/gdb.h> 42131899Smarcel#include <gdb/gdb_int.h> 43131899Smarcel 44131899Smarcelstatic dbbe_init_f gdb_init; 45131899Smarcelstatic dbbe_trap_f gdb_trap; 46131899Smarcel 47131899SmarcelKDB_BACKEND(gdb, gdb_init, NULL, gdb_trap); 48131899Smarcel 49131899SmarcelGDB_DBGPORT(null, NULL, NULL, NULL, NULL, NULL, NULL); 50131899SmarcelSET_DECLARE(gdb_dbgport_set, struct gdb_dbgport); 51131899Smarcel 52131899Smarcelstruct gdb_dbgport *gdb_cur = NULL; 53131899Smarcel 54131899Smarcelstatic int 55131899Smarcelgdb_init(void) 56131899Smarcel{ 57131899Smarcel struct gdb_dbgport *dp, **iter; 58131899Smarcel int cur_pri, pri; 59131899Smarcel 60131899Smarcel gdb_cur = NULL; 61131899Smarcel cur_pri = -1; 62131899Smarcel SET_FOREACH(iter, gdb_dbgport_set) { 63131899Smarcel dp = *iter; 64131899Smarcel pri = (dp->gdb_probe != NULL) ? dp->gdb_probe() : -1; 65131899Smarcel dp->gdb_active = (pri >= 0) ? 0 : -1; 66131899Smarcel if (pri > cur_pri) { 67131899Smarcel cur_pri = pri; 68131899Smarcel gdb_cur = dp; 69131899Smarcel } 70131899Smarcel } 71131899Smarcel if (gdb_cur != NULL) { 72131899Smarcel printf("GDB: debug ports:"); 73131899Smarcel SET_FOREACH(iter, gdb_dbgport_set) { 74131899Smarcel dp = *iter; 75131899Smarcel if (dp->gdb_active == 0) 76131899Smarcel printf(" %s", dp->gdb_name); 77131899Smarcel } 78131899Smarcel printf("\n"); 79131899Smarcel } else 80131899Smarcel printf("GDB: no debug ports present\n"); 81131899Smarcel if (gdb_cur != NULL) { 82131899Smarcel gdb_cur->gdb_init(); 83131899Smarcel printf("GDB: current port: %s\n", gdb_cur->gdb_name); 84131899Smarcel } 85131899Smarcel if (gdb_cur != NULL) 86131899Smarcel cur_pri = (boothowto & RB_GDB) ? 2 : 0; 87131899Smarcel else 88131899Smarcel cur_pri = -1; 89131899Smarcel return (cur_pri); 90131899Smarcel} 91131899Smarcel 92131899Smarcelstatic int 93131899Smarcelgdb_trap(int type, int code) 94131899Smarcel{ 95131899Smarcel struct thread *thr_iter; 96131899Smarcel 97131899Smarcel /* 98131899Smarcel * Send a T packet. We currently do not support watchpoints (the 99131899Smarcel * awatch, rwatch or watch elements). 100131899Smarcel */ 101131899Smarcel gdb_tx_begin('T'); 102131899Smarcel gdb_tx_hex(gdb_cpu_signal(type, code), 2); 103131899Smarcel gdb_tx_varhex(GDB_REG_PC); 104131899Smarcel gdb_tx_char(':'); 105131899Smarcel gdb_tx_reg(GDB_REG_PC); 106131899Smarcel gdb_tx_char(';'); 107131899Smarcel gdb_tx_str("thread:"); 108131899Smarcel gdb_tx_varhex((long)kdb_thread->td_tid); 109131899Smarcel gdb_tx_char(';'); 110131899Smarcel gdb_tx_end(); /* XXX check error condition. */ 111131899Smarcel 112131899Smarcel thr_iter = NULL; 113131899Smarcel while (gdb_rx_begin() == 0) { 114133446Smarcel /* printf("GDB: got '%s'\n", gdb_rxp); */ 115131899Smarcel switch (gdb_rx_char()) { 116131899Smarcel case '?': /* Last signal. */ 117131899Smarcel gdb_tx_begin('S'); 118131899Smarcel gdb_tx_hex(gdb_cpu_signal(type, code), 2); 119131899Smarcel gdb_tx_end(); 120131899Smarcel break; 121131899Smarcel case 'c': { /* Continue. */ 122131899Smarcel uintmax_t addr; 123131899Smarcel if (!gdb_rx_varhex(&addr)) 124131899Smarcel gdb_cpu_setreg(GDB_REG_PC, addr); 125131899Smarcel kdb_cpu_clear_singlestep(); 126131899Smarcel return (1); 127131899Smarcel } 128131899Smarcel case 'C': { /* Continue with signal. */ 129131899Smarcel uintmax_t addr, sig; 130131899Smarcel if (!gdb_rx_varhex(&sig) && gdb_rx_char() == ';' && 131131899Smarcel !gdb_rx_varhex(&addr)) 132131899Smarcel gdb_cpu_setreg(GDB_REG_PC, addr); 133131899Smarcel kdb_cpu_clear_singlestep(); 134131899Smarcel return (1); 135131899Smarcel } 136131899Smarcel case 'g': { /* Read registers. */ 137131899Smarcel size_t r; 138131899Smarcel gdb_tx_begin(0); 139131899Smarcel for (r = 0; r < GDB_NREGS; r++) 140131899Smarcel gdb_tx_reg(r); 141131899Smarcel gdb_tx_end(); 142131899Smarcel break; 143131899Smarcel } 144131899Smarcel case 'G': /* Write registers. */ 145131899Smarcel gdb_tx_err(0); 146131899Smarcel break; 147131899Smarcel case 'H': { /* Set thread. */ 148131899Smarcel intmax_t tid; 149131899Smarcel struct thread *thr; 150131899Smarcel gdb_rx_char(); 151131899Smarcel gdb_rx_varhex(&tid); 152131899Smarcel if (tid > 0) { 153131899Smarcel thr = kdb_thr_lookup(tid); 154131899Smarcel if (thr == NULL) { 155131899Smarcel gdb_tx_err(ENOENT); 156131899Smarcel break; 157131899Smarcel } 158131899Smarcel kdb_thr_select(thr); 159131899Smarcel } 160131899Smarcel gdb_tx_ok(); 161131899Smarcel break; 162131899Smarcel } 163131899Smarcel case 'k': /* Kill request. */ 164131899Smarcel kdb_cpu_clear_singlestep(); 165131899Smarcel return (1); 166131899Smarcel case 'm': { /* Read memory. */ 167131899Smarcel uintmax_t addr, size; 168131899Smarcel if (gdb_rx_varhex(&addr) || gdb_rx_char() != ',' || 169131899Smarcel gdb_rx_varhex(&size)) { 170131899Smarcel gdb_tx_err(EINVAL); 171131899Smarcel break; 172131899Smarcel } 173131899Smarcel gdb_tx_begin(0); 174131899Smarcel if (gdb_tx_mem((char *)(uintptr_t)addr, size)) 175131899Smarcel gdb_tx_end(); 176131899Smarcel else 177131899Smarcel gdb_tx_err(EIO); 178131899Smarcel break; 179131899Smarcel } 180131899Smarcel case 'M': { /* Write memory. */ 181131899Smarcel uintmax_t addr, size; 182131899Smarcel if (gdb_rx_varhex(&addr) || gdb_rx_char() != ',' || 183131899Smarcel gdb_rx_varhex(&size) || gdb_rx_char() != ':') { 184131899Smarcel gdb_tx_err(EINVAL); 185131899Smarcel break; 186131899Smarcel } 187131899Smarcel if (gdb_rx_mem((char *)(uintptr_t)addr, size) == 0) 188131899Smarcel gdb_tx_err(EIO); 189131899Smarcel else 190131899Smarcel gdb_tx_ok(); 191131899Smarcel break; 192131899Smarcel } 193131899Smarcel case 'P': { /* Write register. */ 194131899Smarcel uintmax_t reg, val; 195131899Smarcel if (gdb_rx_varhex(®) || gdb_rx_char() != '=' || 196131899Smarcel gdb_rx_varhex(&val)) { 197131899Smarcel gdb_tx_err(EINVAL); 198131899Smarcel break; 199131899Smarcel } 200131899Smarcel gdb_cpu_setreg(reg, val); 201131899Smarcel gdb_tx_ok(); 202131899Smarcel break; 203131899Smarcel } 204131899Smarcel case 'q': /* General query. */ 205131899Smarcel if (gdb_rx_equal("fThreadInfo")) { 206131899Smarcel thr_iter = kdb_thr_first(); 207131899Smarcel gdb_tx_begin('m'); 208131899Smarcel gdb_tx_hex((long)thr_iter->td_tid, 8); 209131899Smarcel gdb_tx_end(); 210131899Smarcel } else if (gdb_rx_equal("sThreadInfo")) { 211131899Smarcel if (thr_iter == NULL) { 212131899Smarcel gdb_tx_err(ENXIO); 213131899Smarcel break; 214131899Smarcel } 215131899Smarcel thr_iter = kdb_thr_next(thr_iter); 216131899Smarcel if (thr_iter != NULL) { 217131899Smarcel gdb_tx_begin('m'); 218131899Smarcel gdb_tx_hex((long)thr_iter->td_tid, 8); 219131899Smarcel gdb_tx_end(); 220131899Smarcel } else { 221131899Smarcel gdb_tx_begin('l'); 222131899Smarcel gdb_tx_end(); 223131899Smarcel } 224131899Smarcel } else if (!gdb_cpu_query()) 225131899Smarcel gdb_tx_empty(); 226131899Smarcel break; 227131899Smarcel case 's': { /* Step. */ 228131899Smarcel uintmax_t addr; 229131899Smarcel if (!gdb_rx_varhex(&addr)) 230131899Smarcel gdb_cpu_setreg(GDB_REG_PC, addr); 231131899Smarcel kdb_cpu_set_singlestep(); 232131899Smarcel return (1); 233131899Smarcel } 234131899Smarcel case 'S': { /* Step with signal. */ 235131899Smarcel uintmax_t addr, sig; 236131899Smarcel if (!gdb_rx_varhex(&sig) && gdb_rx_char() == ';' && 237131899Smarcel !gdb_rx_varhex(&addr)) 238131899Smarcel gdb_cpu_setreg(GDB_REG_PC, addr); 239131899Smarcel kdb_cpu_set_singlestep(); 240131899Smarcel return (1); 241131899Smarcel } 242131899Smarcel case 'T': { /* Thread alive. */ 243131899Smarcel intmax_t tid; 244131899Smarcel gdb_rx_varhex(&tid); 245131899Smarcel if (kdb_thr_lookup(tid) != NULL) 246131899Smarcel gdb_tx_ok(); 247131899Smarcel else 248131899Smarcel gdb_tx_err(ENOENT); 249131899Smarcel break; 250131899Smarcel } 251131899Smarcel case -1: 252131899Smarcel /* Empty command. Treat as unknown command. */ 253131899Smarcel /* FALLTHROUGH */ 254131899Smarcel default: 255131899Smarcel /* Unknown command. Send empty response. */ 256131899Smarcel gdb_tx_empty(); 257131899Smarcel break; 258131899Smarcel } 259131899Smarcel } 260131899Smarcel return (0); 261131899Smarcel} 262