Commit 039d3da3 authored by bellard's avatar bellard
Browse files

added user mode libqemu usage example


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@739 c046a42c-6fe2-441c-8c8c-71466251a162
parent a7e61ed4
......@@ -62,6 +62,11 @@ speed: sha1 sha1-i386
runcom: runcom.c
$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $<
# NOTE: -fomit-frame-pointer is currently needed : this is a bug in libqemu
qruncom: qruncom.c ../i386-user/libqemu.a
$(CC) $(CFLAGS) -fomit-frame-pointer $(LDFLAGS) -I../target-i386 -I.. -I../i386-user \
-o $@ $< -L../i386-user -lqemu -lm
# arm test
hello-arm: hello-arm.o
arm-linux-ld -o $@ $<
......
File added
/*
* Example of use of user mode libqemu: launch a basic .com DOS
* executable
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <signal.h>
#include "cpu.h"
//#define SIGTEST
CPUState *cpu_single_env = NULL;
void cpu_outb(CPUState *env, int addr, int val)
{
fprintf(stderr, "outb: port=0x%04x, data=%02x\n", addr, val);
}
void cpu_outw(CPUState *env, int addr, int val)
{
fprintf(stderr, "outw: port=0x%04x, data=%04x\n", addr, val);
}
void cpu_outl(CPUState *env, int addr, int val)
{
fprintf(stderr, "outl: port=0x%04x, data=%08x\n", addr, val);
}
int cpu_inb(CPUState *env, int addr)
{
fprintf(stderr, "inb: port=0x%04x\n", addr);
return 0;
}
int cpu_inw(CPUState *env, int addr)
{
fprintf(stderr, "inw: port=0x%04x\n", addr);
return 0;
}
int cpu_inl(CPUState *env, int addr)
{
fprintf(stderr, "inl: port=0x%04x\n", addr);
return 0;
}
int cpu_get_pic_interrupt(CPUState *env)
{
return -1;
}
static void set_gate(void *ptr, unsigned int type, unsigned int dpl,
unsigned long addr, unsigned int sel)
{
unsigned int e1, e2;
e1 = (addr & 0xffff) | (sel << 16);
e2 = (addr & 0xffff0000) | 0x8000 | (dpl << 13) | (type << 8);
stl((uint8_t *)ptr, e1);
stl((uint8_t *)ptr + 4, e2);
}
uint64_t idt_table[256];
/* only dpl matters as we do only user space emulation */
static void set_idt(int n, unsigned int dpl)
{
set_gate(idt_table + n, 0, dpl, 0, 0);
}
void qemu_free(void *ptr)
{
free(ptr);
}
void *qemu_malloc(size_t size)
{
return malloc(size);
}
void qemu_printf(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vprintf(fmt, ap);
va_end(ap);
}
/* XXX: this is a bug in helper2.c */
int errno;
/**********************************************/
#define COM_BASE_ADDR 0x10100
void usage(void)
{
printf("qruncom version 0.1 (c) 2003 Fabrice Bellard\n"
"usage: qruncom file.com\n"
"user mode libqemu demo: run simple .com DOS executables\n");
exit(1);
}
static inline uint8_t *seg_to_linear(unsigned int seg, unsigned int reg)
{
return (uint8_t *)((seg << 4) + (reg & 0xffff));
}
static inline void pushw(CPUState *env, int val)
{
env->regs[R_ESP] = (env->regs[R_ESP] & ~0xffff) | ((env->regs[R_ESP] - 2) & 0xffff);
*(uint16_t *)seg_to_linear(env->segs[R_SS].selector, env->regs[R_ESP]) = val;
}
static void host_segv_handler(int host_signum, siginfo_t *info,
void *puc)
{
if (cpu_signal_handler(host_signum, info, puc)) {
return;
}
abort();
}
int main(int argc, char **argv)
{
uint8_t *vm86_mem;
const char *filename;
int fd, ret, seg;
CPUState *env;
if (argc != 2)
usage();
filename = argv[1];
vm86_mem = mmap((void *)0x00000000, 0x110000,
PROT_WRITE | PROT_READ | PROT_EXEC,
MAP_FIXED | MAP_ANON | MAP_PRIVATE, -1, 0);
if (vm86_mem == MAP_FAILED) {
perror("mmap");
exit(1);
}
/* load the MSDOS .com executable */
fd = open(filename, O_RDONLY);
if (fd < 0) {
perror(filename);
exit(1);
}
ret = read(fd, vm86_mem + COM_BASE_ADDR, 65536 - 256);
if (ret < 0) {
perror("read");
exit(1);
}
close(fd);
/* install exception handler for CPU emulator */
{
struct sigaction act;
sigfillset(&act.sa_mask);
act.sa_flags = SA_SIGINFO;
// act.sa_flags |= SA_ONSTACK;
act.sa_sigaction = host_segv_handler;
sigaction(SIGSEGV, &act, NULL);
sigaction(SIGBUS, &act, NULL);
#if defined (TARGET_I386) && defined(USE_CODE_COPY)
sigaction(SIGFPE, &act, NULL);
#endif
}
// cpu_set_log(CPU_LOG_TB_IN_ASM | CPU_LOG_TB_OUT_ASM | CPU_LOG_EXEC);
env = cpu_init();
/* disable code copy to simplify debugging */
code_copy_enabled = 0;
/* set user mode state (XXX: should be done automatically by
cpu_init ?) */
env->user_mode_only = 1;
cpu_x86_set_cpl(env, 3);
env->cr[0] = CR0_PG_MASK | CR0_WP_MASK | CR0_PE_MASK;
/* NOTE: hflags duplicates some of the virtual CPU state */
env->hflags |= HF_PE_MASK | VM_MASK;
/* flags setup : we activate the IRQs by default as in user
mode. We also activate the VM86 flag to run DOS code */
env->eflags |= IF_MASK | VM_MASK;
/* init basic registers */
env->eip = 0x100;
env->regs[R_ESP] = 0xfffe;
seg = (COM_BASE_ADDR - 0x100) >> 4;
cpu_x86_load_seg_cache(env, R_CS, seg,
(uint8_t *)(seg << 4), 0xffff, 0);
cpu_x86_load_seg_cache(env, R_SS, seg,
(uint8_t *)(seg << 4), 0xffff, 0);
cpu_x86_load_seg_cache(env, R_DS, seg,
(uint8_t *)(seg << 4), 0xffff, 0);
cpu_x86_load_seg_cache(env, R_ES, seg,
(uint8_t *)(seg << 4), 0xffff, 0);
cpu_x86_load_seg_cache(env, R_FS, seg,
(uint8_t *)(seg << 4), 0xffff, 0);
cpu_x86_load_seg_cache(env, R_GS, seg,
(uint8_t *)(seg << 4), 0xffff, 0);
/* exception support */
env->idt.base = (void *)idt_table;
env->idt.limit = sizeof(idt_table) - 1;
set_idt(0, 0);
set_idt(1, 0);
set_idt(2, 0);
set_idt(3, 3);
set_idt(4, 3);
set_idt(5, 3);
set_idt(6, 0);
set_idt(7, 0);
set_idt(8, 0);
set_idt(9, 0);
set_idt(10, 0);
set_idt(11, 0);
set_idt(12, 0);
set_idt(13, 0);
set_idt(14, 0);
set_idt(15, 0);
set_idt(16, 0);
set_idt(17, 0);
set_idt(18, 0);
set_idt(19, 0);
/* put return code */
*seg_to_linear(env->segs[R_CS].selector, 0) = 0xb4; /* mov ah, $0 */
*seg_to_linear(env->segs[R_CS].selector, 1) = 0x00;
*seg_to_linear(env->segs[R_CS].selector, 2) = 0xcd; /* int $0x21 */
*seg_to_linear(env->segs[R_CS].selector, 3) = 0x21;
pushw(env, 0x0000);
/* the value of these registers seem to be assumed by pi_10.com */
env->regs[R_ESI] = 0x100;
env->regs[R_ECX] = 0xff;
env->regs[R_EBP] = 0x0900;
env->regs[R_EDI] = 0xfffe;
/* inform the emulator of the mmaped memory */
page_set_flags(0x00000000, 0x110000,
PAGE_WRITE | PAGE_READ | PAGE_EXEC | PAGE_VALID);
for(;;) {
ret = cpu_x86_exec(env);
switch(ret) {
case EXCP0D_GPF:
{
int int_num, ah;
int_num = *(env->segs[R_CS].base + env->eip + 1);
if (int_num != 0x21)
goto unknown_int;
ah = (env->regs[R_EAX] >> 8) & 0xff;
switch(ah) {
case 0x00: /* exit */
exit(0);
case 0x02: /* write char */
{
uint8_t c = env->regs[R_EDX];
write(1, &c, 1);
}
break;
case 0x09: /* write string */
{
uint8_t c;
for(;;) {
c = *seg_to_linear(env->segs[R_DS].selector, env->regs[R_EAX]);
if (c == '$')
break;
write(1, &c, 1);
}
env->regs[R_EAX] = (env->regs[R_EAX] & ~0xff) | '$';
}
break;
default:
unknown_int:
fprintf(stderr, "unsupported int 0x%02x\n", int_num);
cpu_dump_state(env, stderr, 0);
// exit(1);
}
env->eip += 2;
}
break;
default:
fprintf(stderr, "unhandled cpu_exec return code (0x%x)\n", ret);
cpu_dump_state(env, stderr, 0);
exit(1);
}
}
}
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