1 /*- 2 * Copyright (c) 2004 Marcel Moolenaar 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/systm.h> 32 #include <sys/ctype.h> 33 #include <sys/kdb.h> 34 35 #include <machine/gdb_machdep.h> 36 #include <machine/kdb.h> 37 38 #include <gdb/gdb.h> 39 #include <gdb/gdb_int.h> 40 41 static char gdb_rxbuf[GDB_BUFSZ]; 42 char *gdb_rxp = NULL; 43 size_t gdb_rxsz = 0; 44 static char gdb_txbuf[GDB_BUFSZ]; 45 char *gdb_txp = NULL; /* Used in inline functions. */ 46 47 #define C2N(c) (((c) < 'A') ? (c) - '0' : \ 48 10 + (((c) < 'a') ? (c) - 'A' : (c) - 'a')) 49 #define N2C(n) (((n) < 10) ? (n) + '0' : (n) + 'a' - 10) 50 51 /* 52 * Get a single character 53 */ 54 55 static int 56 gdb_getc(void) 57 { 58 int c; 59 60 do 61 c = gdb_cur->gdb_getc(); 62 while (c == -1); 63 return (c); 64 } 65 66 /* 67 * Functions to receive and extract from a packet. 68 */ 69 70 int 71 gdb_rx_begin(void) 72 { 73 int c, cksum; 74 75 gdb_rxp = NULL; 76 do { 77 /* 78 * Wait for the start character, ignore all others. 79 * XXX needs a timeout. 80 */ 81 while ((c = gdb_getc()) != '$') 82 ; 83 84 /* Read until a # or end of buffer is found. */ 85 cksum = 0; 86 gdb_rxsz = 0; 87 while (gdb_rxsz < sizeof(gdb_rxbuf) - 1) { 88 c = gdb_getc(); 89 if (c == '#') 90 break; 91 gdb_rxbuf[gdb_rxsz++] = c; 92 cksum += c; 93 } 94 gdb_rxbuf[gdb_rxsz] = 0; 95 cksum &= 0xff; 96 97 /* Bail out on a buffer overflow. */ 98 if (c != '#') { 99 gdb_cur->gdb_putc('-'); 100 return (ENOSPC); 101 } 102 103 c = gdb_getc(); 104 cksum -= (C2N(c) << 4) & 0xf0; 105 c = gdb_getc(); 106 cksum -= C2N(c) & 0x0f; 107 gdb_cur->gdb_putc((cksum == 0) ? '+' : '-'); 108 if (cksum != 0) 109 printf("GDB: packet `%s' has invalid checksum\n", 110 gdb_rxbuf); 111 } while (cksum != 0); 112 113 gdb_rxp = gdb_rxbuf; 114 return (0); 115 } 116 117 int 118 gdb_rx_equal(const char *str) 119 { 120 int len; 121 122 len = strlen(str); 123 if (len > gdb_rxsz || strncmp(str, gdb_rxp, len) != 0) 124 return (0); 125 gdb_rxp += len; 126 gdb_rxsz -= len; 127 return (1); 128 } 129 130 int 131 gdb_rx_mem(unsigned char *addr, size_t size) 132 { 133 unsigned char *p; 134 void *prev; 135 jmp_buf jb; 136 size_t cnt; 137 int ret; 138 unsigned char c; 139 140 if (size * 2 != gdb_rxsz) 141 return (-1); 142 143 prev = kdb_jmpbuf(jb); 144 ret = setjmp(jb); 145 if (ret == 0) { 146 p = addr; 147 cnt = size; 148 while (cnt-- > 0) { 149 c = (C2N(gdb_rxp[0]) << 4) & 0xf0; 150 c |= C2N(gdb_rxp[1]) & 0x0f; 151 *p++ = c; 152 gdb_rxsz -= 2; 153 gdb_rxp += 2; 154 } 155 kdb_cpu_sync_icache(addr, size); 156 } 157 (void)kdb_jmpbuf(prev); 158 return ((ret == 0) ? 1 : 0); 159 } 160 161 int 162 gdb_rx_varhex(uintmax_t *vp) 163 { 164 uintmax_t v; 165 int c, neg; 166 167 c = gdb_rx_char(); 168 neg = (c == '-') ? 1 : 0; 169 if (neg == 1) 170 c = gdb_rx_char(); 171 if (!isxdigit(c)) { 172 gdb_rxp -= ((c == -1) ? 0 : 1) + neg; 173 gdb_rxsz += ((c == -1) ? 0 : 1) + neg; 174 return (-1); 175 } 176 v = 0; 177 do { 178 v <<= 4; 179 v += C2N(c); 180 c = gdb_rx_char(); 181 } while (isxdigit(c)); 182 if (c != -1) { 183 gdb_rxp--; 184 gdb_rxsz++; 185 } 186 *vp = (neg) ? -v : v; 187 return (0); 188 } 189 190 /* 191 * Function to build and send a package. 192 */ 193 194 void 195 gdb_tx_begin(char tp) 196 { 197 198 gdb_txp = gdb_txbuf; 199 if (tp != '\0') 200 gdb_tx_char(tp); 201 } 202 203 int 204 gdb_tx_end(void) 205 { 206 const char *p; 207 int runlen; 208 unsigned char c, cksum; 209 210 do { 211 gdb_cur->gdb_putc('$'); 212 213 cksum = 0; 214 p = gdb_txbuf; 215 while (p < gdb_txp) { 216 /* Send a character and start run-length encoding. */ 217 c = *p++; 218 gdb_cur->gdb_putc(c); 219 cksum += c; 220 runlen = 0; 221 /* Determine run-length and update checksum. */ 222 while (p < gdb_txp && *p == c) { 223 runlen++; 224 p++; 225 } 226 /* Emit the run-length encoded string. */ 227 while (runlen >= 97) { 228 gdb_cur->gdb_putc('*'); 229 cksum += '*'; 230 gdb_cur->gdb_putc(97+29); 231 cksum += 97+29; 232 runlen -= 97; 233 if (runlen > 0) { 234 gdb_cur->gdb_putc(c); 235 cksum += c; 236 runlen--; 237 } 238 } 239 if (runlen == 1) { 240 gdb_cur->gdb_putc(c); 241 cksum += c; 242 runlen--; 243 } 244 if (runlen == 0) 245 continue; 246 /* Don't emit '$', '#', '+' or '-'. */ 247 if (runlen == 7) { 248 gdb_cur->gdb_putc(c); 249 cksum += c; 250 runlen--; 251 } 252 if (runlen == 6 || runlen == 14 || runlen == 16) { 253 gdb_cur->gdb_putc(c); 254 cksum += c; 255 runlen--; 256 } 257 gdb_cur->gdb_putc('*'); 258 cksum += '*'; 259 gdb_cur->gdb_putc(runlen+29); 260 cksum += runlen+29; 261 } 262 263 gdb_cur->gdb_putc('#'); 264 c = cksum >> 4; 265 gdb_cur->gdb_putc(N2C(c)); 266 c = cksum & 0x0f; 267 gdb_cur->gdb_putc(N2C(c)); 268 269 c = gdb_getc(); 270 } while (c != '+'); 271 272 return (0); 273 } 274 275 int 276 gdb_tx_mem(const unsigned char *addr, size_t size) 277 { 278 void *prev; 279 jmp_buf jb; 280 int ret; 281 282 prev = kdb_jmpbuf(jb); 283 ret = setjmp(jb); 284 if (ret == 0) { 285 while (size-- > 0) { 286 *gdb_txp++ = N2C(*addr >> 4); 287 *gdb_txp++ = N2C(*addr & 0x0f); 288 addr++; 289 } 290 } 291 (void)kdb_jmpbuf(prev); 292 return ((ret == 0) ? 1 : 0); 293 } 294 295 void 296 gdb_tx_reg(int regnum) 297 { 298 unsigned char *regp; 299 size_t regsz; 300 301 regp = gdb_cpu_getreg(regnum, ®sz); 302 if (regp == NULL) { 303 /* Register unavailable. */ 304 while (regsz--) { 305 gdb_tx_char('x'); 306 gdb_tx_char('x'); 307 } 308 } else 309 gdb_tx_mem(regp, regsz); 310 } 311