1 /* 2 * emu main 3 * 4 * Copyright (c) 2003 Fabrice Bellard 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program 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 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 19 */ 20 #include <stdlib.h> 21 #include <stdio.h> 22 #include <stdarg.h> 23 #include <errno.h> 24 #include <unistd.h> 25 26 #include "gemu.h" 27 28 #include "cpu-i386.h" 29 30 #define DEBUG_LOGFILE "/tmp/gemu.log" 31 32 FILE *logfile = NULL; 33 int loglevel; 34 35 unsigned long x86_stack_size; 36 unsigned long stktop; 37 38 void gemu_log(const char *fmt, ...) 39 { 40 va_list ap; 41 42 va_start(ap, fmt); 43 vfprintf(stderr, fmt, ap); 44 va_end(ap); 45 } 46 47 /***********************************************************/ 48 /* CPUX86 core interface */ 49 50 void cpu_x86_outb(int addr, int val) 51 { 52 fprintf(stderr, "outb: port=0x%04x, data=%02x\n", addr, val); 53 } 54 55 void cpu_x86_outw(int addr, int val) 56 { 57 fprintf(stderr, "outw: port=0x%04x, data=%04x\n", addr, val); 58 } 59 60 void cpu_x86_outl(int addr, int val) 61 { 62 fprintf(stderr, "outl: port=0x%04x, data=%08x\n", addr, val); 63 } 64 65 int cpu_x86_inb(int addr) 66 { 67 fprintf(stderr, "inb: port=0x%04x\n", addr); 68 return 0; 69 } 70 71 int cpu_x86_inw(int addr) 72 { 73 fprintf(stderr, "inw: port=0x%04x\n", addr); 74 return 0; 75 } 76 77 int cpu_x86_inl(int addr) 78 { 79 fprintf(stderr, "inl: port=0x%04x\n", addr); 80 return 0; 81 } 82 83 84 /* XXX: currently we use LDT entries */ 85 #define __USER_CS (0x23|4) 86 #define __USER_DS (0x2B|4) 87 88 void usage(void) 89 { 90 printf("gemu version 0.1, Copyright (c) 2003 Fabrice Bellard\n" 91 "usage: gemu [-d] program [arguments...]\n" 92 "Linux x86 emulator\n" 93 ); 94 exit(1); 95 } 96 97 int main(int argc, char **argv) 98 { 99 const char *filename; 100 struct target_pt_regs regs1, *regs = ®s1; 101 struct image_info info1, *info = &info1; 102 CPUX86State *env; 103 int optind; 104 105 if (argc <= 1) 106 usage(); 107 loglevel = 0; 108 optind = 1; 109 if (argv[optind] && !strcmp(argv[optind], "-d")) { 110 loglevel = 1; 111 optind++; 112 } 113 filename = argv[optind]; 114 115 /* init debug */ 116 if (loglevel) { 117 logfile = fopen(DEBUG_LOGFILE, "w"); 118 if (!logfile) { 119 perror(DEBUG_LOGFILE); 120 exit(1); 121 } 122 setvbuf(logfile, NULL, _IOLBF, 0); 123 } 124 125 /* Zero out regs */ 126 memset(regs, 0, sizeof(struct target_pt_regs)); 127 128 /* Zero out image_info */ 129 memset(info, 0, sizeof(struct image_info)); 130 131 if(elf_exec(filename, argv+optind, environ, regs, info) != 0) { 132 printf("Error loading %s\n", filename); 133 exit(1); 134 } 135 136 if (loglevel) { 137 fprintf(logfile, "start_brk 0x%08lx\n" , info->start_brk); 138 fprintf(logfile, "end_code 0x%08lx\n" , info->end_code); 139 fprintf(logfile, "start_code 0x%08lx\n" , info->start_code); 140 fprintf(logfile, "end_data 0x%08lx\n" , info->end_data); 141 fprintf(logfile, "start_stack 0x%08lx\n" , info->start_stack); 142 fprintf(logfile, "brk 0x%08lx\n" , info->brk); 143 fprintf(logfile, "esp 0x%08lx\n" , regs->esp); 144 fprintf(logfile, "eip 0x%08lx\n" , regs->eip); 145 } 146 147 target_set_brk((char *)info->brk); 148 syscall_init(); 149 150 env = cpu_x86_init(); 151 152 env->regs[R_EAX] = regs->eax; 153 env->regs[R_EBX] = regs->ebx; 154 env->regs[R_ECX] = regs->ecx; 155 env->regs[R_EDX] = regs->edx; 156 env->regs[R_ESI] = regs->esi; 157 env->regs[R_EDI] = regs->edi; 158 env->regs[R_EBP] = regs->ebp; 159 env->regs[R_ESP] = regs->esp; 160 env->segs[R_CS] = __USER_CS; 161 env->segs[R_DS] = __USER_DS; 162 env->segs[R_ES] = __USER_DS; 163 env->segs[R_SS] = __USER_DS; 164 env->segs[R_FS] = __USER_DS; 165 env->segs[R_GS] = __USER_DS; 166 env->pc = regs->eip; 167 168 #if 0 169 LDT[__USER_CS >> 3].w86Flags = DF_PRESENT | DF_PAGES | DF_32; 170 LDT[__USER_CS >> 3].dwSelLimit = 0xfffff; 171 LDT[__USER_CS >> 3].lpSelBase = NULL; 172 173 LDT[__USER_DS >> 3].w86Flags = DF_PRESENT | DF_PAGES | DF_32; 174 LDT[__USER_DS >> 3].dwSelLimit = 0xfffff; 175 LDT[__USER_DS >> 3].lpSelBase = NULL; 176 #endif 177 178 for(;;) { 179 int err; 180 uint8_t *pc; 181 182 err = cpu_x86_exec(env); 183 switch(err) { 184 case EXCP0D_GPF: 185 pc = (uint8_t *)env->pc; 186 if (pc[0] == 0xcd && pc[1] == 0x80) { 187 /* syscall */ 188 env->pc += 2; 189 env->regs[R_EAX] = do_syscall(env->regs[R_EAX], 190 env->regs[R_EBX], 191 env->regs[R_ECX], 192 env->regs[R_EDX], 193 env->regs[R_ESI], 194 env->regs[R_EDI], 195 env->regs[R_EBP]); 196 } else { 197 goto trap_error; 198 } 199 break; 200 default: 201 trap_error: 202 fprintf(stderr, "0x%08lx: Unknown exception %d, aborting\n", 203 (long)env->pc, err); 204 abort(); 205 } 206 } 207 return 0; 208 } 209