1/**************************************************************************** 2* 3* Realmode X86 Emulator Library 4* 5* Copyright (C) 1996-1999 SciTech Software, Inc. 6* Copyright (C) David Mosberger-Tang 7* Copyright (C) 1999 Egbert Eich 8* 9* ======================================================================== 10* 11* Permission to use, copy, modify, distribute, and sell this software and 12* its documentation for any purpose is hereby granted without fee, 13* provided that the above copyright notice appear in all copies and that 14* both that copyright notice and this permission notice appear in 15* supporting documentation, and that the name of the authors not be used 16* in advertising or publicity pertaining to distribution of the software 17* without specific, written prior permission. The authors makes no 18* representations about the suitability of this software for any purpose. 19* It is provided "as is" without express or implied warranty. 20* 21* THE AUTHORS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, 22* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO 23* EVENT SHALL THE AUTHORS BE LIABLE FOR ANY SPECIAL, INDIRECT OR 24* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF 25* USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR 26* OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 27* PERFORMANCE OF THIS SOFTWARE. 28* 29* ======================================================================== 30* 31* Language: ANSI C 32* Environment: Any 33* Developer: Kendall Bennett 34* 35* Description: This file contains the code to handle debugging of the 36* emulator. 37* 38****************************************************************************/ 39/* $XFree86: xc/extras/x86emu/src/x86emu/debug.c,v 1.4 2000/04/17 16:29:45 eich Exp $ */ 40 41#include "x86emu/x86emui.h" 42#ifdef IN_MODULE 43#include "xf86_ansic.h" 44#else 45#include <stdarg.h> 46#ifndef _CFE_ 47#include <stdlib.h> 48#endif 49#endif 50 51#ifdef _CFE_ 52#include "cfe_console.h" 53#endif 54 55 56/*----------------------------- Implementation ----------------------------*/ 57 58#ifdef DEBUG 59 60static void print_encoded_bytes (u16 s, u16 o); 61static void print_decoded_instruction (void); 62static int parse_line (char *s, int *ps, int *n); 63 64/* should look something like debug's output. */ 65void X86EMU_trace_regs (void) 66{ 67 if (DEBUG_TRACE()) { 68 x86emu_dump_regs(); 69 } 70 if (DEBUG_DECODE() && ! DEBUG_DECODE_NOPRINT()) { 71 printk("%04x:%04x ",M.x86.saved_cs, M.x86.saved_ip); 72 print_encoded_bytes( M.x86.saved_cs, M.x86.saved_ip); 73 print_decoded_instruction(); 74 } 75} 76 77void X86EMU_trace_xregs (void) 78{ 79 if (DEBUG_TRACE()) { 80 x86emu_dump_xregs(); 81 } 82} 83 84void x86emu_just_disassemble (void) 85{ 86 /* 87 * This routine called if the flag DEBUG_DISASSEMBLE is set kind 88 * of a hack! 89 */ 90 printk("%04x:%04x ",M.x86.saved_cs, M.x86.saved_ip); 91 print_encoded_bytes( M.x86.saved_cs, M.x86.saved_ip); 92 print_decoded_instruction(); 93} 94 95static u16 disassemble_forward (u16 seg, u16 off, int n) 96{ 97 X86EMU_sysEnv tregs; 98 int i; 99 u8 op1; 100 u16 finaloffset; 101 /* 102 * hack, hack, hack. What we do is use the exact machinery set up 103 * for execution, except that now there is an additional state 104 * flag associated with the "execution", and we are using a copy 105 * of the register struct. All the major opcodes, once fully 106 * decoded, have the following two steps: TRACE_REGS(r,m); 107 * SINGLE_STEP(r,m); which disappear if DEBUG is not defined to 108 * the preprocessor. The TRACE_REGS macro expands to: 109 * 110 * if (debug&DEBUG_DISASSEMBLE) 111 * {just_disassemble(); goto EndOfInstruction;} 112 * if (debug&DEBUG_TRACE) trace_regs(r,m); 113 * 114 * ...... and at the last line of the routine. 115 * 116 * EndOfInstruction: end_instr(); 117 * 118 * Up to the point where TRACE_REG is expanded, NO modifications 119 * are done to any register EXCEPT the IP register, for fetch and 120 * decoding purposes. 121 * 122 * This was done for an entirely different reason, but makes a 123 * nice way to get the system to help debug codes. 124 */ 125 tregs = M; 126 M.x86.R_IP = off; 127 M.x86.R_CS = seg; 128 M.x86.saved_ip = off; 129 M.x86.saved_cs = seg; 130 131 /* reset the decoding buffers */ 132 M.x86.enc_str_pos = 0; 133 M.x86.enc_pos = 0; 134 135 /* turn on the "disassemble only, no execute" flag */ 136 M.x86.debug |= DEBUG_DISASSEMBLE_F; 137 138 /* DUMP NEXT n instructions to screen in straight_line fashion */ 139 for (i=0; i<n; i++) { 140 op1 = (*sys_rdb)(((u32)M.x86.R_CS<<4) + (M.x86.R_IP++)); 141 INC_DECODED_INST_LEN(1); 142 (x86emu_optab[op1])(op1); 143 M.x86.saved_ip = M.x86.R_IP; 144 } 145 finaloffset = M.x86.R_IP; 146 M = tregs; 147 /* end major hack mode. */ 148 return finaloffset; 149} 150 151void x86emu_check_ip_access (void) 152{ 153 /* NULL as of now */ 154} 155 156void x86emu_check_sp_access (void) 157{ 158} 159 160void x86emu_check_mem_access (u32 dummy) 161{ 162 /* check bounds, etc */ 163} 164 165void x86emu_check_data_access (uint dummy1, uint dummy2) 166{ 167 /* check bounds, etc */ 168} 169 170void x86emu_inc_decoded_inst_len (int x) 171{ 172 M.x86.enc_pos += x; 173} 174 175void x86emu_decode_printf (char *x) 176{ 177 sprintf(M.x86.decoded_buf+M.x86.enc_str_pos,"%s",x); 178 M.x86.enc_str_pos += strlen(x); 179} 180 181void x86emu_decode_printf2 (char *x, int y) 182{ 183 char temp[100]; 184 sprintf(temp,x,y); 185 sprintf(M.x86.decoded_buf+M.x86.enc_str_pos,"%s",temp); 186 M.x86.enc_str_pos += strlen(temp); 187} 188 189void x86emu_end_instr (void) 190{ 191 M.x86.enc_str_pos = 0; 192 M.x86.enc_pos = 0; 193} 194 195static void print_encoded_bytes (u16 s, u16 o) 196{ 197 int i; 198 char buf1[64]; 199 buf1[0] = 0; 200 for (i=0; i< M.x86.enc_pos; i++) { 201 sprintf(buf1+2*i,"%02x", fetch_data_byte_abs(s,o+i)); 202 } 203 printk("%-20s",buf1); 204} 205 206static void print_decoded_instruction (void) 207{ 208 printk("%s", M.x86.decoded_buf); 209} 210 211void x86emu_print_int_vect (u16 iv) 212{ 213 u16 seg,off; 214 215 if (iv > 256) return; 216 seg = fetch_data_word_abs(0,iv*4); 217 off = fetch_data_word_abs(0,iv*4+2); 218 printk("%04x:%04x ", seg, off); 219} 220 221void X86EMU_dump_memory (u16 seg, u16 off, u32 amt) 222{ 223 u32 start = off & 0xfffffff0; 224 u32 end = (off+16) & 0xfffffff0; 225 u32 i; 226 u32 current; 227 228 current = start; 229 while (end <= off + amt) { 230 printk("%04x:%04x ", seg, start); 231 for (i=start; i< off; i++) 232 printk(" "); 233 for ( ; i< end; i++) 234 printk("%02x ", fetch_data_byte_abs(seg,i)); 235 printk("\n"); 236 start = end; 237 end = start + 16; 238 } 239} 240 241void x86emu_single_step (void) 242{ 243 char s[1024]; 244 int ps[10]; 245 int ntok; 246 int cmd; 247 int done; 248 int segment; 249 int offset; 250 static int breakpoint; 251 static int noDecode = 1; 252 253 char *p; 254 255 if (DEBUG_BREAK()) { 256 if (M.x86.saved_ip != breakpoint) { 257 return; 258 } 259 else { 260 M.x86.debug &= ~DEBUG_DECODE_NOPRINT_F; 261 M.x86.debug |= DEBUG_TRACE_F; 262 M.x86.debug &= ~DEBUG_BREAK_F; 263 print_decoded_instruction (); 264 X86EMU_trace_regs(); 265 } 266 } 267 done=0; 268 offset = M.x86.saved_ip; 269 while (!done) { 270#ifdef _CFE_ 271 cmd = console_readline("-",s,1023); 272 if (cmd) { s[cmd] = '\n'; s[cmd+1] = 0;} 273 p = s; 274#else 275 printk("-"); 276 p = fgets(s, 1023, stdin); 277#endif 278 cmd = parse_line(s, ps, &ntok); 279 switch(cmd) { 280 case 'u': 281 if (ntok == 2) { offset = ps[1]; } 282 offset = disassemble_forward(M.x86.saved_cs,(u16)offset,10); 283 break; 284 case 'd': 285 if (ntok == 2) { 286 segment = M.x86.saved_cs; 287 offset = ps[1]; 288 X86EMU_dump_memory(segment,(u16)offset,16); 289 offset += 16; 290 } else if (ntok == 3) { 291 segment = ps[1]; 292 offset = ps[2]; 293 X86EMU_dump_memory(segment,(u16)offset,16); 294 offset += 16; 295 } else { 296 segment = M.x86.saved_cs; 297 X86EMU_dump_memory(segment,(u16)offset,16); 298 offset += 16; 299 } 300 break; 301 case 'c': 302 M.x86.debug ^= DEBUG_TRACECALL_F; 303 break; 304 case 's': 305 M.x86.debug ^= DEBUG_SVC_F | DEBUG_SYS_F | DEBUG_SYSINT_F; 306 break; 307 case 'r': 308 X86EMU_trace_regs(); 309 break; 310 case 'x': 311 X86EMU_trace_xregs(); 312 break; 313 case 'g': 314 if (ntok == 2) { 315 breakpoint = ps[1]; 316 if (noDecode) { 317 M.x86.debug |= DEBUG_DECODE_NOPRINT_F; 318 } else { 319 M.x86.debug &= ~DEBUG_DECODE_NOPRINT_F; 320 } 321 M.x86.debug &= ~DEBUG_TRACE_F; 322 M.x86.debug |= DEBUG_BREAK_F; 323 done = 1; 324 } 325 break; 326 case 'q': 327 M.x86.debug &= ~DEBUG_TRACE_F; 328 M.x86.debug &= ~DEBUG_BREAK_F; 329 M.x86.debug &= ~DEBUG_STEP_F; 330 M.x86.debug &= ~DEBUG_DECODE_F; 331 done = 1; 332 break; 333 case 'P': 334 noDecode = (noDecode)?0:1; 335 printk("Toggled decoding to %s\n",(noDecode)?"FALSE":"TRUE"); 336 break; 337 case 't': 338 case 0: 339 done = 1; 340 break; 341 } 342 } 343} 344 345int X86EMU_trace_on(void) 346{ 347 return M.x86.debug |= DEBUG_STEP_F | DEBUG_DECODE_F | DEBUG_TRACE_F; 348} 349 350int X86EMU_trace_off(void) 351{ 352 return M.x86.debug &= ~(DEBUG_STEP_F | DEBUG_DECODE_F | DEBUG_TRACE_F); 353} 354 355static int parse_line (char *s, int *ps, int *n) 356{ 357 int cmd; 358 359 *n = 0; 360 while(*s == ' ' || *s == '\t') s++; 361 ps[*n] = *s; 362 switch (*s) { 363 case '\n': 364 *n += 1; 365 return 0; 366 default: 367 cmd = *s; 368 *n += 1; 369 } 370 371 while (1) { 372 while (*s != ' ' && *s != '\t' && *s != '\n') s++; 373 374 if (*s == '\n') 375 return cmd; 376 377 while(*s == ' ' || *s == '\t') s++; 378#ifdef _CFE_ 379 ps[*n] = xtoi(s); 380#else 381 sscanf(s,"%x",&ps[*n]); 382#endif 383 *n += 1; 384 } 385} 386 387#endif /* DEBUG */ 388 389void x86emu_dump_regs (void) 390{ 391 printk("\tAX=%04x ", M.x86.R_AX ); 392 printk("BX=%04x ", M.x86.R_BX ); 393 printk("CX=%04x ", M.x86.R_CX ); 394 printk("DX=%04x ", M.x86.R_DX ); 395 printk("SP=%04x ", M.x86.R_SP ); 396 printk("BP=%04x ", M.x86.R_BP ); 397 printk("SI=%04x ", M.x86.R_SI ); 398 printk("DI=%04x\n", M.x86.R_DI ); 399 printk("\tDS=%04x ", M.x86.R_DS ); 400 printk("ES=%04x ", M.x86.R_ES ); 401 printk("SS=%04x ", M.x86.R_SS ); 402 printk("CS=%04x ", M.x86.R_CS ); 403 printk("IP=%04x ", M.x86.R_IP ); 404 if (ACCESS_FLAG(F_OF)) printk("OV "); /* CHECKED... */ 405 else printk("NV "); 406 if (ACCESS_FLAG(F_DF)) printk("DN "); 407 else printk("UP "); 408 if (ACCESS_FLAG(F_IF)) printk("EI "); 409 else printk("DI "); 410 if (ACCESS_FLAG(F_SF)) printk("NG "); 411 else printk("PL "); 412 if (ACCESS_FLAG(F_ZF)) printk("ZR "); 413 else printk("NZ "); 414 if (ACCESS_FLAG(F_AF)) printk("AC "); 415 else printk("NA "); 416 if (ACCESS_FLAG(F_PF)) printk("PE "); 417 else printk("PO "); 418 if (ACCESS_FLAG(F_CF)) printk("CY "); 419 else printk("NC "); 420 printk("\n"); 421} 422 423void x86emu_dump_xregs (void) 424{ 425 printk("\tEAX=%08x ", M.x86.R_EAX ); 426 printk("EBX=%08x ", M.x86.R_EBX ); 427 printk("ECX=%08x ", M.x86.R_ECX ); 428 printk("EDX=%08x \n", M.x86.R_EDX ); 429 printk("\tESP=%08x ", M.x86.R_ESP ); 430 printk("EBP=%08x ", M.x86.R_EBP ); 431 printk("ESI=%08x ", M.x86.R_ESI ); 432 printk("EDI=%08x\n", M.x86.R_EDI ); 433 printk("\tDS=%04x ", M.x86.R_DS ); 434 printk("ES=%04x ", M.x86.R_ES ); 435 printk("SS=%04x ", M.x86.R_SS ); 436 printk("CS=%04x ", M.x86.R_CS ); 437 printk("EIP=%08x\n\t", M.x86.R_EIP ); 438 if (ACCESS_FLAG(F_OF)) printk("OV "); /* CHECKED... */ 439 else printk("NV "); 440 if (ACCESS_FLAG(F_DF)) printk("DN "); 441 else printk("UP "); 442 if (ACCESS_FLAG(F_IF)) printk("EI "); 443 else printk("DI "); 444 if (ACCESS_FLAG(F_SF)) printk("NG "); 445 else printk("PL "); 446 if (ACCESS_FLAG(F_ZF)) printk("ZR "); 447 else printk("NZ "); 448 if (ACCESS_FLAG(F_AF)) printk("AC "); 449 else printk("NA "); 450 if (ACCESS_FLAG(F_PF)) printk("PE "); 451 else printk("PO "); 452 if (ACCESS_FLAG(F_CF)) printk("CY "); 453 else printk("NC "); 454 printk("\n"); 455} 456