tests/qruncom.c: Remove libqemu.a example (e4aeadcb) · Commits · SUMMER2020 / students / proj-2021291

tests/qruncom.c

deleted100644 → 0

+0 −284

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		/*
		* 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 <malloc.h>

		#include "cpu.h"

		//#define SIGTEST

		int cpu_get_pic_interrupt(CPUState *env)
		{
		return -1;
		}

		uint64_t cpu_get_tsc(CPUState *env)
		{
		return 0;
		}

		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 g_free(void *ptr)
		{
		free(ptr);
		}

		void *g_malloc(size_t size)
		{
		return malloc(size);
		}

		void *g_malloc0(size_t size)
		{
		void *ptr;
		ptr = g_malloc(size);
		if (!ptr)
		return NULL;
		memset(ptr, 0, size);
		return ptr;
		}

		void *qemu_vmalloc(size_t size)
		{
		return memalign(4096, size);
		}

		void qemu_vfree(void *ptr)
		{
		free(ptr);
		}

		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

		static 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);
		}

		// cpu_set_log(CPU_LOG_TB_IN_ASM \| CPU_LOG_TB_OUT_ASM \| CPU_LOG_EXEC);

		env = cpu_init("qemu32");

		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,
		(seg << 4), 0xffff, 0);
		cpu_x86_load_seg_cache(env, R_SS, seg,
		(seg << 4), 0xffff, 0);
		cpu_x86_load_seg_cache(env, R_DS, seg,
		(seg << 4), 0xffff, 0);
		cpu_x86_load_seg_cache(env, R_ES, seg,
		(seg << 4), 0xffff, 0);
		cpu_x86_load_seg_cache(env, R_FS, seg,
		(seg << 4), 0xffff, 0);
		cpu_x86_load_seg_cache(env, R_GS, seg,
		(seg << 4), 0xffff, 0);

		/* exception support */
		env->idt.base = (unsigned long)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 = (uint8_t )(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, fprintf, 0);
		// exit(1);
		}
		env->eip += 2;
		}
		break;
		default:
		fprintf(stderr, "unhandled cpu_exec return code (0x%x)\n", ret);
		cpu_dump_state(env, stderr, fprintf, 0);
		exit(1);
		}
		}
		}