#define _GNU_SOURCE // for syscall in unistd.h#include <stdio.h>#include <stdlib.h>#include <stdarg.h>#include <string.h>#include <assert.h>#include <unistd.h>#include <errno.h>#include <pthread.h>#include <sys/stat.h>#include <sys/time.h>#include <sys/wait.h>#include <sys/syscall.h>#include <fcntl.h>#include "vx32.h" #define nelem(x) (sizeof(x)/sizeof((x)[0])) extern char *strsyscall(int);  // strsyscall.c static const char *progname; static void fatal(const char *fmt, ...){	va_list ap;	fprintf(stderr, "%s: fatal error: ", progname);	va_start(ap, fmt);	vfprintf(stderr, fmt, ap);	va_end(ap);	fputc('\n', stderr);	exit(2);} static void dumpregs(struct vxproc *p){	struct vxcpu *c = p->cpu; 	fprintf(stderr, "eax %08x  ecx %08x  edx %08x  ebx %08x\n",		c->reg[EAX], c->reg[ECX], c->reg[EDX], c->reg[EBX]);	fprintf(stderr, "esp %08x  ebp %08x  esi %08x  edi %08x\n",		c->reg[ESP], c->reg[EBP], c->reg[ESI], c->reg[EDI]);	fprintf(stderr, "eip %08x  eflags %08x\n",		c->eip, c->eflags); //	for (int i = 0; i < 8; i++) {//		int32_t *val = r.xmm[i].i32;//		fprintf(stderr, "xmm%d %08x%08x%08x%08x\n",//			i, val[3], val[2], val[1], val[0]);//	}} int trace; // macros for use within system calls#define NUM proc->cpu->reg[EAX]#define ARG1 proc->cpu->reg[EBX]#define ARG2 proc->cpu->reg[ECX]#define ARG3 proc->cpu->reg[EDX]#define ARG4 proc->cpu->reg[ESI]#define ARG5 proc->cpu->reg[EDI] #define SYSCALL(x) static int x(vxproc *proc, vxmmap *m) // Translate pointer - guest to host#define TX(a) ((a) ? (a)+m->base : 0) SYSCALL(sys0) { return syscall(NUM); }SYSCALL(sys1I) { return syscall(NUM, ARG1); }SYSCALL(sys1P) { return syscall(NUM, TX(ARG1)); }SYSCALL(sys2II) { return syscall(NUM, ARG1, ARG2); }SYSCALL(sys2IP) { return syscall(NUM, ARG1, TX(ARG2)); }SYSCALL(sys2PI) { return syscall(NUM, TX(ARG1), ARG2); }SYSCALL(sys2PP) { return syscall(NUM, TX(ARG1), TX(ARG2)); }SYSCALL(sys3IIP) { return syscall(NUM, ARG1, ARG2, TX(ARG3)); }SYSCALL(sys3III) { return syscall(NUM, ARG1, ARG2, ARG3); }SYSCALL(sys3PII) { return syscall(NUM, TX(ARG1), ARG2, ARG3); }SYSCALL(sys3PPI) { return syscall(NUM, TX(ARG1), TX(ARG2), ARG3); }SYSCALL(sys3IPI) { return syscall(NUM, ARG1, TX(ARG2), ARG3); }SYSCALL(sys4IPPI) { return syscall(NUM, ARG1, TX(ARG2), TX(ARG3), ARG4); }SYSCALL(sys5IIIPI) { return syscall(NUM, ARG1, ARG2, ARG3, TX(ARG4), ARG5); } // Linux brk doesn't follow the usual system call conventions.// It returns the new brk on success, the old one on failure.SYSCALL(sysbrk){	uint32_t oaddr = m->size;	uint32_t addr = ARG1;	if (addr == 0)		return oaddr;	if (addr == oaddr)		return oaddr;	if (vxmem_resize(proc->mem, addr) < 0)		return oaddr;	if (addr > oaddr)		vxmem_setperm(proc->mem, oaddr, addr - oaddr, VXPERM_READ|VXPERM_WRITE);	return addr;} SYSCALL(sysinval){	errno = EINVAL;	return -1;} SYSCALL(sysfcntl64){	switch (ARG1) {	default:		errno = EINVAL;		return -1; 	case F_DUPFD:	case F_GETFD:	case F_SETFD:	case F_GETFL:	case F_SETFL:	case F_GETOWN:	case F_SETOWN:	case F_GETSIG:	case F_SETSIG:	case F_GETLEASE:	case F_SETLEASE:	case F_NOTIFY:		return syscall(NUM, ARG1, ARG2, ARG3);		case F_GETLK:	case F_SETLK:	case F_SETLKW:		return syscall(NUM, ARG1, ARG2, TX(ARG3));	}} static int (*syscalls[])(vxproc*, vxmmap*) ={	[SYS_brk]           sysbrk,	[SYS_close]         sys1I,	[SYS_chmod]         sys2PI,	[SYS_chown]         sys3PII,	[SYS_creat]         sys2PI,	[SYS_dup]           sys1I,	[SYS_dup2]          sys2II,	[SYS_exit_group]    sys1I,	[SYS_fcntl64]       sysfcntl64,	[SYS_fchmod]        sys2II,	[SYS_fchown]        sys3III,	[SYS_fstat64]       sys2IP,	[SYS_getegid32]     sys0,	[SYS_geteuid32]     sys0,	[SYS_getgid32]      sys0,	[SYS_getpid]        sys0,	[SYS_getuid32]      sys0,	[SYS_ioctl]         sys3IIP,	[SYS__llseek]       sys5IIIPI,	[SYS_lchown]        sys3PII,	[SYS_link]          sys2PP,	[SYS_lseek]         sys3III,	[SYS_mkdir]         sys2PI,	[SYS_mmap]          sysinval,	[SYS_mmap2]         sysinval,	[SYS_open]          sys3PII,	[SYS_read]          sys3IPI,	[SYS_readlink]      sys3PPI,	[SYS_rmdir]         sys1P,	[SYS_rt_sigaction]  sys4IPPI,	[SYS_stat64]        sys2PP,	[SYS_symlink]       sys2PP,	[SYS_time]          sys1P,	[SYS_uname]         sys1P,	[SYS_unlink]        sys1P,	[SYS_write]         sys3IPI,}; static void dosyscall(vxproc *proc){	int n = NUM;	if (trace)		fprintf(stderr, "%s %08x %08x %08x %08x %08x\n", 			strsyscall(NUM), ARG1, ARG2, ARG3, ARG4, ARG5);	if (n < nelem(syscalls) && n >= 0 && syscalls[n]) {		vxmmap *m = vxmem_map(proc->mem, 0);		int ret = syscalls[n](proc, m);		if (n != SYS_brk && ret < 0)			ret = -errno;		vxmem_unmap(proc->mem, m);		proc->cpu->reg[EAX] = ret;		return;	}	dumpregs(proc);	fatal("syscall not implemented - %s", strsyscall(NUM));} extern char **environ; int main(int argc, const char *const *argv){	int i;	progname = argv[0]; 	if (argc > 1 && strcmp(argv[1], "-t") == 0){		argc--;		argv++;		trace++;	} 	if (argc < 2) {		fprintf(stderr, "Usage: %s <vx-program> <args>\n",			progname);		exit(1);	}	const char *loadname = argv[1]; 	FILE *f = fopen("/dev/tty", "w");	if(f){		char buf[1000];		if(getcwd(buf, sizeof buf) != NULL)			fprintf(f, "cd %s\n", buf);		fprintf(f, "vxlinux");		for(i=1; i<argc; i++)			fprintf(f, " %s", argv[i]);		fprintf(f, "\n");	} 	vxproc *p = vxproc_alloc();	if (p == NULL)		fatal("vxproc_new: %s\n", strerror(errno));	p->allowfp = 1; 	if (vxproc_loadelffile(p, loadname, &argv[1], (const char**)environ) < 0)		fatal("vxproc_loadfile: %s\n", strerror(errno)); 	vx32_siginit();	dumpregs(p); 	// Simple execution loop.	for (;;) {		int rc = vxproc_run(p);		if (rc < 0)			fatal("vxproc_run: %s\n", strerror(errno));		if (rc == VXTRAP_SOFT + 0x80) {			dosyscall(p);			continue;		}		dumpregs(p);		fatal("vxproc_run trap %#x\n", rc);	}	return 0;	// not reached}