static char sccsid[] = "@(#)setup.c 4.10 (Berkeley) 85/05/09"; /* * adb - routines to read a.out+core at startup */ #include "defs.h" #include #include #include #include #include off_t datbas; /* offset of the base of the data segment */ off_t stksiz; /* stack size in the core image */ INT sigcode; /* belongs in head.h */ char *symfil = "a.out"; char *corfil = "core"; setsym() { off_t loc; struct exec hdr; register struct nlist *sp; int ssiz; char *strtab; fsym = getfile(symfil, 1); txtmap.ufd = fsym; if (read(fsym, (char *)&hdr, sizeof hdr) != sizeof hdr || N_BADMAG(hdr)) { txtmap.e1 = MAXFILE; return; } filhdr = hdr; loc = filhdr.a_text+filhdr.a_data; txtmap.f1 = txtmap.f2 = N_TXTOFF(filhdr); txtmap.b1 = 0; switch (filhdr.a_magic) { case OMAGIC: txtmap.b1 = txtmap.e1 = 0; txtmap.b2 = datbas = 0; txtmap.e2 = loc; break; case ZMAGIC: case NMAGIC: txtmap.e1 = filhdr.a_text; txtmap.b2 = datbas = round(filhdr.a_text, PAGSIZ); txtmap.e2 = datbas + filhdr.a_data; txtmap.f2 += txtmap.e1; } loc = N_SYMOFF(filhdr); symtab = (struct nlist *) malloc(filhdr.a_syms); esymtab = &symtab[filhdr.a_syms / sizeof (struct nlist)]; if (symtab == NULL) goto nospac; lseek(fsym, loc, L_SET); if (filhdr.a_syms == 0) goto nosymt; /* SHOULD SQUISH OUT STABS HERE!!! */ if (read(fsym, symtab, filhdr.a_syms) != filhdr.a_syms) goto readerr; if (read(fsym, &ssiz, sizeof (ssiz)) != sizeof (ssiz)) goto oldfmt; strtab = (char *) malloc(ssiz); if (strtab == 0) goto nospac; *(int *)strtab = ssiz; ssiz -= sizeof (ssiz); if (read(fsym, strtab + sizeof (ssiz), ssiz) != ssiz) goto readerr; for (sp = symtab; sp < esymtab; sp++) if (sp->n_strx) /* SHOULD PERFORM RANGE CHECK HERE */ sp->n_un.n_name = strtab + sp->n_un.n_strx; nosymt: if (INKERNEL(filhdr.a_entry)) { txtmap.b1 += KERNOFF; txtmap.e1 += KERNOFF; txtmap.b2 += KERNOFF; txtmap.e2 += KERNOFF; } return; readerr: printf("Error reading symbol|string table\n"); exit(1); nospac: printf("Not enough space for symbol|string table\n"); exit(1); oldfmt: printf("Old format a.out - no string table\n"); exit(1); } setcor() { fcor = datmap.ufd = getfile(corfil,2); if (kernel && fcor != -1 && INKERNEL(filhdr.a_entry)) { struct stat stb; kcore = 1; fstat(fcor, &stb); datmap.b1 = 0; datmap.e1 = -1; if (kernel == 0 && (stb.st_mode & S_IFREG)) datmap.b1 = 0x80000000; lookup("_Sysmap"); sbr = cursym->n_value; lookup("_Syssize"); slr = cursym->n_value; printf("sbr %x slr %x\n", sbr, slr); lookup("_masterpaddr"); physrw(fcor, KVTOPH(cursym->n_value), &masterpcbb, 1); masterpcbb = (masterpcbb&PG_PFNUM)*NBPG; getpcb(); findstackframe(); return; } if (read(fcor, (char *)&u, ctob(UPAGES))!=ctob(UPAGES) || !INUDOT(u.u_pcb.pcb_ksp) || !INSTACK(u.u_pcb.pcb_usp)) { datmap.e1 = MAXFILE; return; } signo = u.u_arg[0]; sigcode = u.u_code; filhdr.a_text = ctob(u.u_tsize); filhdr.a_data = ctob(u.u_dsize); stksiz = ctob(u.u_ssize); switch (filhdr.a_magic) { case OMAGIC: datmap.b1 = 0; datmap.e1 = filhdr.a_text+filhdr.a_data; datmap.f2 = ctob(UPAGES) + datmap.e1; break; case NMAGIC: case ZMAGIC: datmap.b1 = round(filhdr.a_text, PAGSIZ); datmap.e1 = datmap.b1 + filhdr.a_data; datmap.f2 = ctob(UPAGES) + filhdr.a_data; break; } datbas = datmap.b1; datmap.f1 = ctob(UPAGES); datmap.b2 = MAXSTOR - stksiz; datmap.e2 = MAXSTOR; } getpcb() { lseek(fcor, KVTOPH(masterpcbb), L_SET); read(fcor, &pcb, sizeof (struct pcb)); pcb.pcb_p0lr &= ~AST_CLR; printf("p0br %x p0lr %x p1br %x p1lr %x\n", pcb.pcb_p0br, pcb.pcb_p0lr, pcb.pcb_p1br, pcb.pcb_p1lr); } caddr_t rpb, scb; caddr_t intstack, eintstack; caddr_t ustack, eustack; struct frame *getframe(); struct frame *checkintstack(); /* * Find the current stack frame when debugging the kernel. * If we're looking at a crash dump and this was not a ``clean'' * crash, then we must search the interrupt stack carefully * looking for a valid frame. */ findstackframe() { char *panicstr, buf[256]; register struct frame *fp; caddr_t addr; register char *cp; int mask; if (lookup("_panicstr") == 0) return; lseek(fcor, KVTOPH(cursym->n_value), L_SET); read(fcor, &panicstr, sizeof (panicstr)); if (panicstr == 0) return; lseek(fcor, KVTOPH((off_t)panicstr), L_SET); read(fcor, buf, sizeof (buf)); for (cp = buf; cp < &buf[sizeof (buf)] && *cp; cp++) if (!isascii(*cp) || (!isprint(*cp) && !isspace(*cp))) *cp = '?'; if (*cp) *cp = '\0'; printf("panic: %s\n", buf); /* * After a panic, look at the top of the rpb stack to * find a stack frame. If this was a clean crash, * i.e. one which left the interrupt and kernel stacks * in a reasonable state, then we should find a pointer * to the proper stack frame here (at location scb-4). * If we don't find a reasonable frame here, then we * must search down through the interrupt stack. */ intstack = lookup("_intstack")->n_value; #define NISP 3 /* from locore.s */ eintstack = intstack + NISP*NBPG; rpb = lookup("_rpb")->n_value; scb = lookup("_scb")->n_value; lookup("_u"); ustack = cursym->n_value + (int)&((struct user *)0)->u_stack[0]; eustack = cursym->n_value + ctob(UPAGES); physrw(fcor, KVTOPH((int)scb - sizeof (caddr_t)), &addr, 1); fp = getframe(fcor, addr); if (fp == 0) fp = checkintstack(); /* search kernel stack? */ if (fp == 0) { printf("can't locate stack frame\n"); return; } /* probably shouldn't clobber pcb, but for now this is easy */ pcb.pcb_fp = addr; pcb.pcb_pc = fp->fr_savpc; pcb.pcb_ap = addr + sizeof (struct frame) + fp->fr_spa; for (mask = fp->fr_mask; mask; mask >>= 1) if (mask & 01) pcb.pcb_ap += sizeof (caddr_t); } /* * Search interrupt stack for a valid frame. */ struct frame * checkintstack(fcor) { char stack[NISP*NBPG]; off_t off = vtophys(intstack); struct frame *fp; register caddr_t addr; if (off == -1 || lseek(fcor, off, L_SET) != off || read(fcor, stack, sizeof (stack)) != sizeof (stack)) return ((struct frame *)0); addr = eintstack; do { addr -= sizeof (caddr_t); fp = (struct frame *)&stack[addr - intstack]; } while (addr >= intstack + sizeof (struct frame) && !checkframe(fp)); return (addr < intstack+sizeof (struct frame) ? (struct frame *)0 : fp); } /* * Get a stack frame and verify it looks like * something which might be on a kernel stack. */ struct frame * getframe(fcor, fp) int fcor; caddr_t fp; { static struct frame frame; off_t off; if (!kstackaddr(fp) || (off = vtophys(fp)) == -1) return ((struct frame *)0); if (lseek(fcor, off, L_SET) != off || read(fcor, &frame, sizeof (frame)) != sizeof (frame)) return ((struct frame *)0); if (!checkframe(&frame)) return ((struct frame *)0); return (&frame); } /* * Check a call frame to see if it's ok as * a kernel stack frame. */ checkframe(fp) register struct frame *fp; { if (fp->fr_handler != 0 || fp->fr_s == 0) return (0); if (!kstackaddr(fp->fr_savap) || !kstackaddr(fp->fr_savfp)) return (0); return (within(fp->fr_savpc, txtmap.b1, txtmap.e1)); } /* * Check if an address is in one of the kernel's stacks: * interrupt stack, rpb stack (during restart sequence), * or u. stack. */ kstackaddr(addr) caddr_t addr; { return (within(addr, intstack, eintstack) || within(addr, rpb + sizeof (struct rpb), scb) || within(addr, ustack, eustack)); } create(f) char *f; { register int fd; fd = creat(f, 0644); if (fd < 0) return (-1); close(fd); return (open(f, wtflag)); } getfile(filnam, cnt) char *filnam; { register int fsym; if (eqstr(filnam, "-")) return (-1); fsym = open(filnam, wtflag); if (fsym < 0 && xargc > cnt) { if (wtflag) fsym = create(filnam); if (fsym < 0) printf("cannot open `%s'\n", filnam); } return (fsym); } setvar() { var[varchk('b')] = datbas; var[varchk('d')] = filhdr.a_data; var[varchk('e')] = filhdr.a_entry; var[varchk('m')] = filhdr.a_magic; var[varchk('s')] = stksiz; var[varchk('t')] = filhdr.a_text; }