+#define FBSD
+/*
+ * Compatability mode support under UNIX-32V
+ * written by Art Wetzel during August 1979
+ * at the Interdisciplinary Dept of Information Science
+ * Room 711, LIS Bldg
+ * University of Pittsburgh
+ * Pittsburgh, Pa 15260
+ *
+ * No claims are made on the completeness of the support of any
+ * of the systems simulated under this package
+ */
+#include <stdio.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include "defs.h"
+#ifdef UNIX
+#include "unixhdr.h"
+#endif
+#ifdef RT11
+#include "rt11.h"
+#endif
+struct stat stat32v;
+unsigned short regs[8];
+unsigned long psl;
+unsigned short *pc;
+int incompat;
+char *progname;
+char *nameend;
+main(argc, argv, envp) int argc; char **argv, **envp; {
+ if(argc < 2){
+ fprintf(stderr,"Usage: %s [-rootdir] file args...\n",argv[0]);
+ exit(1);
+ }
+ /* remember where the program name etc should go for using ps */
+ progname = argv[0];
+ nameend = envp[0]-1;
+ argv++;
+ /* set up alternate root directory if flagged for */
+ if(*argv[0] == '-') {
+ if(chroot(argv[0]+1)) {
+ fprintf(stderr,"Can't change root to %s\n",argv[0]+1);
+ exit(-1);
+ }
+ argv++;
+ }
+ /* check out file stats of file to run */
+ if(stat(argv[0], &stat32v)) {
+ fprintf(stderr,"%s does not exist\n",argv[0]);
+ exit(1);
+ }
+ /* a version of SETUID and SETGID file executions */
+ /* the binary of this program should be SETUID root for this to work */
+ /* requires nonstandard seteuid and setegid sys calls */
+ if(!(stat32v.st_mode & S_ISGID) || setegid(stat32v.st_gid))
+ /* if not SETGID file or error, drop back to real group */
+ setgid(getgid());
+ if(!(stat32v.st_mode & S_ISUID) || seteuid(stat32v.st_uid))
+ /* if not SETUID file or error, drop back to real uid */
+ setuid(getuid());
+#ifdef V6UNIX
+ /* no umasks in version 6 */
+ umask(0);
+#endif
+ /* go try to execute , passing along args and environment */
+ execute(argv[0], argv, envp);
+ /* only get here if execute fails */
+ fprintf(stderr,"Execution failure on %s\n",argv[0]);
+ exit(1);
+}
+execute(file, argv, envp) char *file, **argv, **envp; {
+ int fd, n, tloadpt, dloadpt, tloadsize, dloadsize, stacksize;
+ register short *p;
+ extern illtrap();
+ extern char **environ;
+ /* file to run should be readable */
+ if((fd = open(file, 0)) == -1) {
+ fprintf(stderr,"Can't open %s for read access\n",file);
+ return(-1);
+ }
+#ifdef UNIX
+ if((n = read(fd, &header, sizeof header)) != sizeof header)
+ return(ENOEXEC);
+ /* check to see if really unix file */
+ if(header.magic != MAGIC1 && header.magic != MAGIC2 &&
+ header.magic != MAGIC3 && header.magic != MAGIC4) {
+ return(ENOEXEC);
+ }
+ /* if a UNIX-32V file run it */
+ if(header.textsize == 0) {
+ close(fd);
+ /* if no explicit env, pass along environ */
+ if(!envp || *envp == 0)
+ return(execve(file, argv, environ));
+ return(execve(file, argv, envp));
+ }
+ /* checks out OK as PDP-11 UNIX file */
+ if(header.magic == MAGIC3) {
+ fprintf(stderr,"%s compiled for separate I/D space\n",argv[0]);
+ return(-1);
+ }
+ /* unix text loads at 0 */
+ tloadpt = 0;
+ /* set starting pc value */
+ pc = (unsigned short *)header.entry;
+ /* figure out where to load initialized data */
+ dloadpt = tloadsize = header.textsize;
+ /* check if alignment of data segment to 8k byte boundary */
+ if(header.magic == MAGIC2)
+ dloadpt = (dloadpt+8191) & (~8191);
+ /* how much data */
+ dloadsize = header.datasize;
+ stacksize = header.bsssize;
+#endif
+#ifdef RT11
+ if((n = read(fd, shortspace, RTHDRSIZ)) != RTHDRSIZ) {
+ fprintf(stderr,"Error reading 1st block\n");
+ return(-1);
+ }
+ /* rt11 files are 0 aligned including the header */
+ tloadpt = RTHDRSIZ;
+ /* set starting pc value */
+ pc = (unsigned short *)shortspace[RTPC];
+ /* initialize stack location */
+ regs[6] = shortspace[RTSP];
+ /* figure how much to load */
+ dloadpt = tloadsize = shortspace[RTHGH]-RTHDRSIZ;
+ /* no separate data as in unix */
+ dloadsize = 0;
+ stacksize = 0;
+#endif
+ /* see if it all fits into available memory space */
+ if((dloadpt+dloadsize+stacksize) > (int)memsiz) {
+ fprintf(stderr,"File too big to run\n");
+ return(-1);
+ }
+ /* read text segment */
+ if((n = read(fd, tloadpt, tloadsize)) < tloadsize) {
+ fprintf(stderr,"Text read failure\n");
+ return(-1);
+ }
+ /* read data segment */
+ if((n = read(fd, dloadpt, dloadsize)) < dloadsize) {
+ fprintf(stderr,"Data read failure\n");
+ return(-1);
+ }
+ /* clear out the rest of memory */
+ p = (short *)(dloadpt + dloadsize);
+ while(p < (short *)memsiz) *p++ = 0;
+ /* close file before starting it */
+ close(fd);
+ /* set up illegal instruction trapping */
+ signal(SIGILL, illtrap);
+ /* lets give it a try */
+ start(argv, envp);
+}
+#ifdef FBSD
+illtrap(signum,faultcode,myaddr,stpc,stps) int signum; {
+#else
+illtrap(){
+#endif
+ unsigned short *pcptr;
+ int instr;
+ register int i;
+ extern getregs();
+ /* record the fact that we are not in compatability mode now */
+ incompat = 0;
+ /* get the register values before they get clobbered */
+ getregs();
+ /* figure out what the pc was */
+#ifdef FBSD
+ pcptr = (unsigned short *) &stpc;
+#else
+ pcptr = (unsigned short *)((char *)&pcptr + 20);
+#endif
+ pc = (unsigned short *) *pcptr;
+ /* get the instruction */
+ instr = *pc;
+ /* incriment the pc over this instruction */
+ pc++;
+ /* set register 7 as pc synonym */
+ regs[7] = (unsigned short)(int)pc;
+ /* set up psl with condition codes */
+ /* a UNIX-32V monitor patch is required to not clear condition codes */
+#ifdef FBSD
+ psl = 0x83c00000 | (stps & 017);
+#else
+ psl = 0x83c00000 | (*(pcptr - 6) & 017);
+#endif
+ /* pick out the appropriate action for this illegal instruction */
+ switch(instr>>8){
+ case TRAPS:
+ dotrap(instr & 0377);
+ break;
+ case EMTS:
+ if(sigvals[SIGEMT] && ((sigvals[SIGEMT]%2) != 1)) {
+ dosig(SIGEMT, pc);
+ break;
+ }
+ doemt(instr & 0377);
+ break;
+ default:
+ if(instr >= 075000 && instr < 075040) {
+ /* fis instructions */
+ if(dofloat(instr) == 0)
+ break;
+ }
+ if(instr >= 0170000) {
+ /* floating point unit instructions */
+ if(dofloat(instr) == 0)
+ break;
+ }
+ /* genuine illegal instruction */
+ /* if signal trap set go to user's trap location */
+ if(sigvals[SIGILL] && ((sigvals[SIGILL]%2) != 1)) {
+ dosig(SIGILL, pc);
+ break;
+ }
+ /* ignore uncaught setd instructions */
+ if(instr == SETD)
+ break;
+ /* otherwise put out a message and quit */
+ printf("illegal instruction, psl 0x%08x, pc 0%04o\n",psl,pc-1);
+ for(i=0; i<7; i++) printf("0x%04x ",regs[i]);
+ printf("0x%04x -> 0%o\n",pc-1,instr);
+ /* set up to dump on illegal instruction */
+ signal(SIGILL,SIG_DFL);
+ /* set pc back to bad instruction */
+ pc--;
+ /* go do it again for dump */
+ compat();
+ }
+ /* go back to compatability mode */
+ incompat++;
+ compat();
+}
projects / unix-history / commitdiff