]>
Commit | Line | Data |
---|---|---|
039d3da3 FB |
1 | /* |
2 | * Example of use of user mode libqemu: launch a basic .com DOS | |
3 | * executable | |
4 | */ | |
5 | #include <stdlib.h> | |
6 | #include <stdio.h> | |
7 | #include <string.h> | |
8 | #include <inttypes.h> | |
9 | #include <unistd.h> | |
10 | #include <fcntl.h> | |
11 | #include <sys/mman.h> | |
12 | #include <signal.h> | |
2d7a3b9d | 13 | #include <malloc.h> |
039d3da3 FB |
14 | |
15 | #include "cpu.h" | |
16 | ||
17 | //#define SIGTEST | |
18 | ||
039d3da3 FB |
19 | int cpu_get_pic_interrupt(CPUState *env) |
20 | { | |
21 | return -1; | |
22 | } | |
23 | ||
28ab0e2e FB |
24 | uint64_t cpu_get_tsc(CPUState *env) |
25 | { | |
26 | return 0; | |
27 | } | |
28 | ||
5fafdf24 | 29 | static void set_gate(void *ptr, unsigned int type, unsigned int dpl, |
039d3da3 FB |
30 | unsigned long addr, unsigned int sel) |
31 | { | |
32 | unsigned int e1, e2; | |
33 | e1 = (addr & 0xffff) | (sel << 16); | |
34 | e2 = (addr & 0xffff0000) | 0x8000 | (dpl << 13) | (type << 8); | |
35 | stl((uint8_t *)ptr, e1); | |
36 | stl((uint8_t *)ptr + 4, e2); | |
37 | } | |
38 | ||
39 | uint64_t idt_table[256]; | |
40 | ||
41 | /* only dpl matters as we do only user space emulation */ | |
42 | static void set_idt(int n, unsigned int dpl) | |
43 | { | |
44 | set_gate(idt_table + n, 0, dpl, 0, 0); | |
45 | } | |
46 | ||
7267c094 | 47 | void g_free(void *ptr) |
039d3da3 FB |
48 | { |
49 | free(ptr); | |
50 | } | |
51 | ||
7267c094 | 52 | void *g_malloc(size_t size) |
039d3da3 FB |
53 | { |
54 | return malloc(size); | |
55 | } | |
56 | ||
7267c094 | 57 | void *g_malloc0(size_t size) |
2d7a3b9d FB |
58 | { |
59 | void *ptr; | |
7267c094 | 60 | ptr = g_malloc(size); |
2d7a3b9d FB |
61 | if (!ptr) |
62 | return NULL; | |
63 | memset(ptr, 0, size); | |
64 | return ptr; | |
65 | } | |
66 | ||
67 | void *qemu_vmalloc(size_t size) | |
68 | { | |
69 | return memalign(4096, size); | |
70 | } | |
71 | ||
72 | void qemu_vfree(void *ptr) | |
73 | { | |
74 | free(ptr); | |
75 | } | |
76 | ||
039d3da3 FB |
77 | void qemu_printf(const char *fmt, ...) |
78 | { | |
79 | va_list ap; | |
80 | va_start(ap, fmt); | |
81 | vprintf(fmt, ap); | |
82 | va_end(ap); | |
83 | } | |
84 | ||
85 | /* XXX: this is a bug in helper2.c */ | |
86 | int errno; | |
87 | ||
88 | /**********************************************/ | |
89 | ||
90 | #define COM_BASE_ADDR 0x10100 | |
91 | ||
051eb6c1 | 92 | static void usage(void) |
039d3da3 FB |
93 | { |
94 | printf("qruncom version 0.1 (c) 2003 Fabrice Bellard\n" | |
95 | "usage: qruncom file.com\n" | |
96 | "user mode libqemu demo: run simple .com DOS executables\n"); | |
97 | exit(1); | |
98 | } | |
99 | ||
100 | static inline uint8_t *seg_to_linear(unsigned int seg, unsigned int reg) | |
101 | { | |
102 | return (uint8_t *)((seg << 4) + (reg & 0xffff)); | |
103 | } | |
104 | ||
105 | static inline void pushw(CPUState *env, int val) | |
106 | { | |
107 | env->regs[R_ESP] = (env->regs[R_ESP] & ~0xffff) | ((env->regs[R_ESP] - 2) & 0xffff); | |
108 | *(uint16_t *)seg_to_linear(env->segs[R_SS].selector, env->regs[R_ESP]) = val; | |
109 | } | |
110 | ||
5fafdf24 | 111 | static void host_segv_handler(int host_signum, siginfo_t *info, |
039d3da3 FB |
112 | void *puc) |
113 | { | |
114 | if (cpu_signal_handler(host_signum, info, puc)) { | |
115 | return; | |
116 | } | |
117 | abort(); | |
118 | } | |
119 | ||
120 | int main(int argc, char **argv) | |
121 | { | |
122 | uint8_t *vm86_mem; | |
123 | const char *filename; | |
124 | int fd, ret, seg; | |
125 | CPUState *env; | |
126 | ||
127 | if (argc != 2) | |
128 | usage(); | |
129 | filename = argv[1]; | |
3b46e624 | 130 | |
5fafdf24 TS |
131 | vm86_mem = mmap((void *)0x00000000, 0x110000, |
132 | PROT_WRITE | PROT_READ | PROT_EXEC, | |
039d3da3 FB |
133 | MAP_FIXED | MAP_ANON | MAP_PRIVATE, -1, 0); |
134 | if (vm86_mem == MAP_FAILED) { | |
135 | perror("mmap"); | |
136 | exit(1); | |
137 | } | |
138 | ||
139 | /* load the MSDOS .com executable */ | |
140 | fd = open(filename, O_RDONLY); | |
141 | if (fd < 0) { | |
142 | perror(filename); | |
143 | exit(1); | |
144 | } | |
145 | ret = read(fd, vm86_mem + COM_BASE_ADDR, 65536 - 256); | |
146 | if (ret < 0) { | |
147 | perror("read"); | |
148 | exit(1); | |
149 | } | |
150 | close(fd); | |
151 | ||
152 | /* install exception handler for CPU emulator */ | |
153 | { | |
154 | struct sigaction act; | |
3b46e624 | 155 | |
039d3da3 FB |
156 | sigfillset(&act.sa_mask); |
157 | act.sa_flags = SA_SIGINFO; | |
158 | // act.sa_flags |= SA_ONSTACK; | |
159 | ||
160 | act.sa_sigaction = host_segv_handler; | |
161 | sigaction(SIGSEGV, &act, NULL); | |
162 | sigaction(SIGBUS, &act, NULL); | |
039d3da3 FB |
163 | } |
164 | ||
165 | // cpu_set_log(CPU_LOG_TB_IN_ASM | CPU_LOG_TB_OUT_ASM | CPU_LOG_EXEC); | |
166 | ||
aaed909a | 167 | env = cpu_init("qemu32"); |
039d3da3 | 168 | |
039d3da3 FB |
169 | cpu_x86_set_cpl(env, 3); |
170 | ||
171 | env->cr[0] = CR0_PG_MASK | CR0_WP_MASK | CR0_PE_MASK; | |
172 | /* NOTE: hflags duplicates some of the virtual CPU state */ | |
173 | env->hflags |= HF_PE_MASK | VM_MASK; | |
174 | ||
175 | /* flags setup : we activate the IRQs by default as in user | |
176 | mode. We also activate the VM86 flag to run DOS code */ | |
177 | env->eflags |= IF_MASK | VM_MASK; | |
3b46e624 | 178 | |
039d3da3 FB |
179 | /* init basic registers */ |
180 | env->eip = 0x100; | |
181 | env->regs[R_ESP] = 0xfffe; | |
182 | seg = (COM_BASE_ADDR - 0x100) >> 4; | |
183 | ||
5fafdf24 | 184 | cpu_x86_load_seg_cache(env, R_CS, seg, |
2d7a3b9d | 185 | (seg << 4), 0xffff, 0); |
5fafdf24 | 186 | cpu_x86_load_seg_cache(env, R_SS, seg, |
2d7a3b9d | 187 | (seg << 4), 0xffff, 0); |
5fafdf24 | 188 | cpu_x86_load_seg_cache(env, R_DS, seg, |
2d7a3b9d | 189 | (seg << 4), 0xffff, 0); |
5fafdf24 | 190 | cpu_x86_load_seg_cache(env, R_ES, seg, |
2d7a3b9d | 191 | (seg << 4), 0xffff, 0); |
5fafdf24 | 192 | cpu_x86_load_seg_cache(env, R_FS, seg, |
2d7a3b9d | 193 | (seg << 4), 0xffff, 0); |
5fafdf24 | 194 | cpu_x86_load_seg_cache(env, R_GS, seg, |
2d7a3b9d | 195 | (seg << 4), 0xffff, 0); |
039d3da3 FB |
196 | |
197 | /* exception support */ | |
2d7a3b9d | 198 | env->idt.base = (unsigned long)idt_table; |
039d3da3 FB |
199 | env->idt.limit = sizeof(idt_table) - 1; |
200 | set_idt(0, 0); | |
201 | set_idt(1, 0); | |
202 | set_idt(2, 0); | |
203 | set_idt(3, 3); | |
204 | set_idt(4, 3); | |
205 | set_idt(5, 3); | |
206 | set_idt(6, 0); | |
207 | set_idt(7, 0); | |
208 | set_idt(8, 0); | |
209 | set_idt(9, 0); | |
210 | set_idt(10, 0); | |
211 | set_idt(11, 0); | |
212 | set_idt(12, 0); | |
213 | set_idt(13, 0); | |
214 | set_idt(14, 0); | |
215 | set_idt(15, 0); | |
216 | set_idt(16, 0); | |
217 | set_idt(17, 0); | |
218 | set_idt(18, 0); | |
219 | set_idt(19, 0); | |
3b46e624 | 220 | |
039d3da3 FB |
221 | /* put return code */ |
222 | *seg_to_linear(env->segs[R_CS].selector, 0) = 0xb4; /* mov ah, $0 */ | |
223 | *seg_to_linear(env->segs[R_CS].selector, 1) = 0x00; | |
224 | *seg_to_linear(env->segs[R_CS].selector, 2) = 0xcd; /* int $0x21 */ | |
225 | *seg_to_linear(env->segs[R_CS].selector, 3) = 0x21; | |
226 | pushw(env, 0x0000); | |
227 | ||
228 | /* the value of these registers seem to be assumed by pi_10.com */ | |
229 | env->regs[R_ESI] = 0x100; | |
230 | env->regs[R_ECX] = 0xff; | |
231 | env->regs[R_EBP] = 0x0900; | |
232 | env->regs[R_EDI] = 0xfffe; | |
233 | ||
234 | /* inform the emulator of the mmaped memory */ | |
5fafdf24 | 235 | page_set_flags(0x00000000, 0x110000, |
039d3da3 FB |
236 | PAGE_WRITE | PAGE_READ | PAGE_EXEC | PAGE_VALID); |
237 | ||
238 | for(;;) { | |
239 | ret = cpu_x86_exec(env); | |
240 | switch(ret) { | |
241 | case EXCP0D_GPF: | |
242 | { | |
243 | int int_num, ah; | |
2d7a3b9d | 244 | int_num = *(uint8_t *)(env->segs[R_CS].base + env->eip + 1); |
039d3da3 FB |
245 | if (int_num != 0x21) |
246 | goto unknown_int; | |
247 | ah = (env->regs[R_EAX] >> 8) & 0xff; | |
248 | switch(ah) { | |
249 | case 0x00: /* exit */ | |
250 | exit(0); | |
251 | case 0x02: /* write char */ | |
252 | { | |
253 | uint8_t c = env->regs[R_EDX]; | |
254 | write(1, &c, 1); | |
255 | } | |
256 | break; | |
257 | case 0x09: /* write string */ | |
258 | { | |
259 | uint8_t c; | |
260 | for(;;) { | |
261 | c = *seg_to_linear(env->segs[R_DS].selector, env->regs[R_EAX]); | |
262 | if (c == '$') | |
263 | break; | |
264 | write(1, &c, 1); | |
265 | } | |
266 | env->regs[R_EAX] = (env->regs[R_EAX] & ~0xff) | '$'; | |
267 | } | |
268 | break; | |
269 | default: | |
270 | unknown_int: | |
271 | fprintf(stderr, "unsupported int 0x%02x\n", int_num); | |
2d7a3b9d | 272 | cpu_dump_state(env, stderr, fprintf, 0); |
039d3da3 FB |
273 | // exit(1); |
274 | } | |
275 | env->eip += 2; | |
276 | } | |
277 | break; | |
278 | default: | |
279 | fprintf(stderr, "unhandled cpu_exec return code (0x%x)\n", ret); | |
2d7a3b9d | 280 | cpu_dump_state(env, stderr, fprintf, 0); |
039d3da3 FB |
281 | exit(1); |
282 | } | |
283 | } | |
284 | } |