minix/commands/postmort/postmort.c
2010-06-10 14:04:46 +00:00

657 lines
17 KiB
C

/* postmort - post mortem dump Author: C. W. Rose */
/* Postmort: perform post-mortem on PC Minix 1.7 core files.
*
*/
/* The 1.5 core file structure is a struct mem_map, the segment memory map,
* followed by a struct proc, the process table, followed by a dump of the
* text, data, and stack segments.
*
* This is the 8086/Intel version; 386 and 68K will differ. It defaults to
* using the name 'core' for the core file, and 'a.out' for the symbol file.
* If there is no 'a.out', it will try and read the symbol table from
* 'symbol.out', then give up. A non-existant symbol table is not a fatal
* error unless the -s option was used.
*
* The PC 1.5 kernel dump routines are odd - they dump the memory maps twice,
* the second time as part of the kernel process table, and the kernel
* process table size must be a multiple of 4. Should a core file have a
* header with a magic number in future?
*
* The kernel include file paths need to be edited for each machine. */
#include <sys/types.h>
#include <minix/config.h>
#include <minix/const.h>
#include <minix/type.h>
#include <minix/ipc.h>
#include <limits.h>
#include <timers.h>
#include <signal.h>
#include <stdlib.h>
#undef EXTERN /* <minix/const.h> defined this */
#define EXTERN /* so we get proc & mproc */
#include <machine/archtypes.h>
#include "kernel/const.h"
#include "kernel/type.h"
#include "kernel/proc.h"
#undef printf /* kernel's const.h defined this */
#include "pm/mproc.h"
#include <a.out.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#undef NULL
#include <string.h>
#include <unistd.h>
#define FALSE 0
#undef TRUE
#define TRUE ~FALSE
#define OK 1
#define FAILED -1
#define CORE "core"
#define AOUT "a.out"
#define SYMB "symbol.out"
#define LINE_LEN 16
#define MAXSYM 200
#define SYMLEN 8
/* Global variables */
int opt_c = FALSE; /* name of core file */
int opt_d = FALSE; /* dump raw data and stack segments */
int opt_p = FALSE; /* dump the kernel process table */
int opt_s = FALSE; /* name of symbol file */
int opt_t = FALSE; /* trace back the stack */
int opt_x = FALSE; /* debugging flag */
char progname[20]; /* program name */
char *segment_name[] = { /* array of segment names */
"Text",
"Data",
"Stack"
};
int dbglvl = 0; /* debugging level */
int maxsym; /* maximum symbol number */
unsigned int baseptr; /* reference copy of stack base pointer */
unsigned int stackptr; /* reference copy of stack pointer */
long int lengths[NR_LOCAL_SEGS]; /* segment lengths */
long int bases[NR_LOCAL_SEGS]; /* segment base addresses */
struct sym { /* symbol table addresses and labels */
unsigned int addr;
char label[SYMLEN + 1];
} symtab[MAXSYM];
/* Used by getopt(3) package */
extern int optind, opterr, optopt;
extern char *optarg;
_PROTOTYPE(int binary, (int uc, char *sp));
_PROTOTYPE(void dump_all_segs, (int fd));
_PROTOTYPE(void dump_maps, (struct mem_map * mp));
_PROTOTYPE(void dump_one_seg, (int fd, int segindex));
_PROTOTYPE(void dump_proc_table, (struct proc * pt));
_PROTOTYPE(void dump_registers, (struct proc * pt));
_PROTOTYPE(void dump_sym_tab, (struct sym *st));
_PROTOTYPE(void dump_stack, (struct stackframe_s * sp));
_PROTOTYPE(int main, (int argc, char *argv[]));
_PROTOTYPE(int parse_line, (char *ps));
_PROTOTYPE(int read_symbol, (int fd));
_PROTOTYPE(void stack_trace, (int fd));
_PROTOTYPE(void usage, (void));
/* B i n a r y
*
* Produce a binary representation of an 8-bit number.
*/
int binary(ucc, sp)
int ucc;
char *sp;
{
int j;
unsigned char k, uc;
uc = (unsigned char) ucc;
for (k = 0x80, j = 0; j < 8; j++) {
if ((uc & k) == 0)
*sp++ = '0';
else
*sp++ = '1';
if (j == 3) *sp++ = '$';
k >>= 1;
}
*sp = '\0';
return(0);
}
/* D u m p _ a l l _ s e g s
*
* Dump all the segments except for text
*/
void dump_all_segs(fd)
int fd;
{
int j;
long int start;
start = (long) (NR_LOCAL_SEGS * sizeof(struct mem_map)) + sizeof(struct proc);
for (j = 1; j < NR_LOCAL_SEGS; j++) {
start += lengths[j - 1];
(void) lseek(fd, start, 0);
printf("\n");
dump_one_seg(fd, j);
}
}
/* D u m p _ m a p s
*
* Dump the memory maps
*/
void dump_maps(mp)
struct mem_map *mp;
{
int j;
long int vir, phy, len;
printf("\t Virtual\t Physical\tLength\n");
printf("\t address\t address\n");
for (j = 0; j < NR_LOCAL_SEGS; j++) {
vir = (long) mp[j].mem_vir << CLICK_SHIFT;
phy = (long) mp[j].mem_phys << CLICK_SHIFT;
len = (long) mp[j].mem_len << CLICK_SHIFT;
printf("%s:\t0x%08.8lx\t0x%08.8lx\t%8ld (0x%08.8lx)\n",
segment_name[j], vir, phy, len, len);
lengths[j] = len;
bases[j] = vir;
}
}
/* D u m p _ o n e _ s e g
*
* Dump a single segment
*/
void dump_one_seg(fd, segindex)
int fd, segindex;
{
unsigned char dlen[LINE_LEN];
int i, amt, amt_read;
long int len, offset;
printf("%s segment\n\n", segment_name[segindex]);
len = lengths[segindex];
amt = LINE_LEN;
for (offset = 0; offset < len; offset += amt) {
if ((len - offset) < LINE_LEN) amt = (int) (len - offset);
if (dbglvl > 0)
printf("Length %ld, offset %ld, amt %d\n", len, offset, amt);
if ((amt_read = read(fd, (char *) dlen, (unsigned int) amt)) == -1) {
printf("Unexpected end of file\n");
exit(1);
}
printf("%08.8lx: ", bases[segindex] + offset);
for (i = 0; i < amt_read; i++) {
if (i == LINE_LEN / 2) printf("- ");
printf("%02.2x ", dlen[i]);
}
printf(" ");
for (i = 0; i < amt_read; i++) {
if (isprint(dlen[i]))
(void) putchar((char) dlen[i]);
else
(void) putchar('.');
}
(void) putchar('\n');
if (dbglvl > 0 && amt_read != amt)
printf("wanted = %d, got = %d, offset = %ld\n",
amt, amt_read, offset);
}
}
/* D u m p _ p r o c _ t a b l e
*
* Dump the entire kernel proc table
*/
void dump_proc_table(pt)
struct proc *pt;
{
printf("Kernel process table entries:\n\n");
#if 0
printf("Process' registers: 0x%04.4x\n", pt->p_reg); /* struct stackframe_s */
printf("Selector in gdt: 0x%04.4x\n", pt->p_ldt_sel); /* reg_t */
printf("Descriptors for code and data: 0x%04.4x\n", pt->p_ldt[2]); /* struct segdesc_s */
#endif
printf("Number of this process: 0x%04.4x\n", pt->p_nr); /* int */
#if 0
printf("Nonzero if blocked by busy task: 0x%04.4x\n", pt->p_ntf_blocked); /* int */
printf("Nonzero if held by busy syscall: 0x%04.4x\n", pt->p_ntf_held); /* int */
printf("Next in chain of held-up processes: 0x%04.4x\n", pt->p_ntf_nextheld); /* struct proc * */
#endif
printf("SENDING, RECEIVING, etc.: 0x%04.4x\n", pt->p_rts_flags); /* int */
#if 0
printf("Memory map: 0x%04.4x\n", pt->p_map[NR_LOCAL_SEGS]); /* struct mem_map */
#endif
#if DEAD_CODE
printf("Process id passed in from PM: 0x%04.4x\n", pt->p_pid); /* int */
#endif
#if 0
printf("User time in ticks: %ld\n", pt->user_time); /* time_t */
printf("Sys time in ticks: %ld\n", pt->sys_time); /* time_t */
printf("Cumulative user time of children: %ld\n", pt->child_utime); /* time_t */
printf("Cumulative sys time of children: %ld\n", pt->child_stime); /* time_t */
printf("Ticks used in current quantum: %d\n", pt->quantum_time); /* int */
printf("Ticks used in last quantum: %d\n", pt->quantum_last); /* int */
printf("Current priority of the process: %d\n", pt->curr_prio); /* int */
printf("Base priority of the process: %d\n", pt->base_prio); /* int */
printf("Scale for profiling, 0 = none: %u\n", pt->p_pscale); /* unsigned */
printf("Profiling pc lower boundary: %d\n", pt->p_plow); /* vir_bytes */
printf("Profiling pc upper boundary: %d\n", pt->p_phigh); /* vir_bytes */
printf("Profiling buffer: %d\n", pt->p_pbuf); /* vir_bytes */
printf("Profiling buffer size: %d\n", pt->p_psiz); /* vir_bytes */
#endif
#if 0
printf("First proc wishing to send: 0x%04.4x\n", pt->p_callerq); /* struct proc * */
printf("Link to next proc wishing to send: 0x%04.4x\n", pt->p_sendlink); /* struct proc * */
printf("Pointer to message buffer: 0x%04.4x\n", pt->p_messbuf); /* message * */
#endif
printf("Expecting message from: 0x%04.4x\n", pt->p_getfrom_e); /* int */
#if 0
printf("Pointer to next ready process: 0x%04.4x\n", pt->p_nextready); /* struct proc * */
#endif
printf("Bit map for pending signals 1-16: 0x%04.4x\n", pt->p_pending); /* int */
#if 0
printf("Count of pending/unfinished signals: 0x%04.4x\n", pt->p_pendcount); /* unsigned */
#endif
}
/* D u m p _ r e g i s t e r s
*
* Dump the registers from the proc table
*/
void dump_registers(pt)
struct proc *pt;
{
char buff[32];
unsigned char uc;
/* Print the registers */
dump_stack(&pt->p_reg);
/* Build up a binary representation of the signal flags */
uc = (pt->p_pending >> 8) & 0xff;
(void) binary((int) uc, buff);
buff[9] = '$';
uc = pt->p_pending & 0xff;
(void) binary((int) uc, buff + 10);
printf("Pending signals = %s\n", buff);
}
/* D u m p _ s y m _ t a b
*
* Dump the symbol table
*/
void dump_sym_tab(st)
struct sym *st;
{
int j;
printf("Symbol table entries (text):\n\n");
for (j = 0; j < maxsym; j++)
printf("0x%08.8x T %s\n", symtab[j].addr, symtab[j].label);
}
/* D u m p _ s t a c k
*
* Dump the stack frame
*/
void dump_stack(sp)
struct stackframe_s *sp;
{
char buff[32];
unsigned char uc;
/* Build up the binary PSW representation */
uc = (sp->psw >> 8) & 0xff;
(void) binary((int) uc, buff);
uc = sp->psw & 0xff;
buff[9] = '$';
(void) binary((int) uc, buff + 10);
/* Print all the information */
printf("Stack Frame:\tPC = %04.4x\t\t PSW = %s\n",
sp->pc, buff);
printf("\t\t\t\t\tStatus = ____ ODIT SZ_A _P_C\n");
printf(" ax bx cx dx di si\n");
printf(" %04.4x\t%04.4x\t%04.4x\t%04.4x\t%04.4x\t%04.4x\n",
sp->retreg, sp->bx, sp->cx, sp->dx, sp->di, sp->si);
printf(" sp bp ss\n");
printf(" %04.4x\t%04.4x\t%04.4x\n",
sp->sp, sp->fp, sp->ss);
printf(" cs ds es\n");
printf(" %04.4x\t%04.4x\t%04.4x\n",
sp->cs, sp->ds, sp->es);
/* Store for future reference */
stackptr = sp->sp;
baseptr = sp->fp;
if (dbglvl > 0)
printf("\nStack pointer 0x%x, Base pointer 0x%x\n", stackptr, baseptr);
}
/* M a i n
*
* Main program
*/
main(argc, argv)
int argc;
char *argv[];
{
int j, fdc, fds;
char *cp, corefile[132], symbfile[132];
struct proc proc_entry;
struct mem_map mp_segs[NR_LOCAL_SEGS];
/* Initial set up */
if ((cp = strrchr(argv[0], '/')) == (char *) NULL)
cp = argv[0];
else
cp++;
strncpy(progname, cp, 19);
strncpy(corefile, CORE, 131);
strncpy(symbfile, AOUT, 131);
/* Parse arguments */
opterr = 0;
while ((j = getopt(argc, argv, "c:dps:tx:")) != EOF) {
switch (j & 0177) {
case 'c':
opt_c = TRUE;
strncpy(corefile, optarg, 131);
break;
case 'd': opt_d = TRUE; break;
case 'p': opt_p = TRUE; break;
case 's':
opt_s = TRUE;
strncpy(symbfile, optarg, 131);
break;
case 't': opt_t = TRUE; break;
case 'x':
dbglvl = atoi(optarg);
opt_x = TRUE;
break;
case '?':
default:
usage();
exit(1);
break;
}
}
/* We must have a core file */
if ((fdc = open(corefile, O_RDONLY)) == -1) {
fprintf(stderr, "Cannot open %s\n", corefile);
exit(1);
}
/* We'd like an a.out file or a symbol table */
if ((fds = open(symbfile, O_RDONLY)) == -1) {
if (opt_s)
j = FAILED;
else {
strncpy(symbfile, AOUT, 131);
if ((fds = open(symbfile, O_RDONLY)) == -1)
j = FAILED;
else
j = read_symbol(fds);
}
} else
j = read_symbol(fds);
/* Only fatal if we insisted */
if (opt_s && j == FAILED) {
fprintf(stderr, "Cannot find symbols in %s\n", symbfile);
exit(1);
}
/* Read the process table */
if (dbglvl > 0) {
printf("\n");
printf("Size of mproc entry %d\n", NR_LOCAL_SEGS * sizeof(struct mem_map));
printf("Size of process table %d\n", sizeof(proc_entry));
}
if (read(fdc, (char *) mp_segs, sizeof(mp_segs)) != sizeof(mp_segs) ||
read(fdc, (char *) &proc_entry,
sizeof(struct proc)) != sizeof(struct proc)) {
fprintf(stderr, "Cannot open %s\n", corefile);
exit(1);
}
/* Do the work */
#if 0
dump_maps(mp_segs); /* duplicated in the kernel */
printf("\n");
/* XXX broken */
dump_maps(proc_entry.p_map);
#endif
printf("\n");
dump_registers(&proc_entry);
if (opt_t) {
printf("\n");
stack_trace(fdc);
}
if (opt_p) {
printf("\n");
dump_proc_table(&proc_entry);
}
if (opt_d) {
printf("\n");
dump_sym_tab(symtab);
dump_all_segs(fdc);
}
/* Wrap up */
(void) close(fdc);
if (fds != -1) (void) close(fds);
exit(0);
/* NOTREACHED */
}
/* P a r s e _ l i n e
*
* Parse a line of the symbol table
*/
int parse_line(ps)
char *ps;
{
char c, s[80];
int j, k;
unsigned int u;
/* We must have space in the table */
if (maxsym == MAXSYM) return(FAILED);
/* Lines must be a minimum length to contain information */
if (strlen(ps) < 8) return(FAILED);
/* Lines must have a definite structure */
if (ps[1] != ' ' || ps[6] != ' ') return(FAILED);
for (j = 2; j < 6; j++)
if (!isxdigit(ps[j])) return(FAILED);
if (sscanf(ps, "%c %x %s", &c, &u, s) != 3) return (FAILED);
if (dbglvl > 0) printf("Address 0x%04.4x, label %s\n", u, s);
/* Load the symbol table in sorted order */
for (j = 0; j < maxsym; j++) {
if (u < symtab[j].addr) {
for (k = maxsym; k > j; k--) symtab[k] = symtab[k - 1];
break;
}
}
symtab[j].addr = u;
strncpy(symtab[j].label, s, SYMLEN);
maxsym++;
return(OK);
}
/* R e a d _ s y m b o l
*
* Read the symbol table
*/
int read_symbol(fd)
int fd;
{
char sym[80], buff[BUFSIZ];
int j, k, m;
long int offset;
struct exec *ep;
struct nlist *np;
/* We collect only text symbols, since that's all that's needed here */
/* Initialise the buffer */
if ((j = read(fd, buff, BUFSIZ)) == 0 || j == -1) return(FAILED);
k = maxsym = 0;
/* Find out what we've got */
ep = (struct exec *) buff;
np = (struct nlist *) buff;
if (BADMAG(*ep)) {
/* Must be a separate symbol table */
while (TRUE) {
if (buff[k] == 'T') {
for (m = 0; m < 78; m++) {
sym[m] = buff[k];
if (++k == j) {
if ((j = read(fd, buff, BUFSIZ)) == 0 || j == -1)
break;
k = 0;
}
if (buff[k] == '\n') break;
}
sym[m + 1] = '\0';
(void) parse_line(sym);
}
if (++k == j) {
if ((j = read(fd, buff, BUFSIZ)) == 0 || j == -1)
break;
k = 0;
}
}
} else if (ep->a_syms != 0L) {
/* There's symbols in them thar hills */
offset = 8 * sizeof(long) + ep->a_text + ep->a_data;
if (lseek(fd, offset, 0) == -1L) return(FAILED);
/* Symbols are in an unsorted list */
while (read(fd, buff, sizeof(struct nlist)) == sizeof(struct nlist)) {
if (np->n_sclass == (N_TEXT + C_EXT)) { /* external text symbols */
for (j = 0; j < maxsym; j++) {
if (np->n_value < symtab[j].addr) {
for (k = maxsym; k > j; k--)
symtab[k] = symtab[k - 1];
break;
}
}
symtab[j].addr = np->n_value;
strncpy(symtab[j].label, np->n_name, SYMLEN);
if (maxsym++ == MAXSYM) break;
}
}
} else if (opt_s)
return(FAILED);
if (dbglvl > 0) {
for (m = 0; m < maxsym; m++) printf("Addr 0x%04.4x, label %s\n",
symtab[m].addr, symtab[m].label);
printf("Maxsym %d\n", maxsym);
}
return(OK);
}
/* S t a c k _ t r a c e
*
* Trace back down the stack frames.
*
* WARNING: very, very, non-portable code
*/
void stack_trace(fd)
int fd;
{
int j;
unsigned int framepointer, lastpointer, returnvalue, end;
long int offset, bp;
/* Bp actually gives the offset from the base of the data segment */
bp = (long) (NR_LOCAL_SEGS * sizeof(struct mem_map)) + sizeof(struct proc)
+ lengths[0] + lengths[1] - bases[2];
if ((offset = lseek(fd, bp + (long int) baseptr, 0)) == -1L) return;
end = (bases[2] + lengths[2] - 1) & 0xffff;
if (dbglvl > 0)
printf("Baseptr %x, End %x, Bp %ld, Offset %ld\n", baseptr, end, bp, offset);
/* Print the header, then try to backtrace */
printf("Stack back trace:\n\n");
printf("Frame address. Contents. Return address.");
if (maxsym != 0) printf(" Previous label.");
printf("\n");
lastpointer = baseptr;
while (TRUE) {
/* Read the frame pointer and return address values */
if (read(fd, (char *) &framepointer, sizeof(int)) == -1 ||
read(fd, (char *) &returnvalue, sizeof(int)) == -1)
break;
/* Look up the return address - ignored if maxsym == 0 */
for (j = 0; j < maxsym; j++) {
if (symtab[j].addr >= returnvalue) break;
}
if (j > 0) j--;
printf(" 0x%04.4x 0x%04.4x 0x%04.4x %s\n",
lastpointer, framepointer, returnvalue,
(maxsym == 0) ? "" : symtab[j].label);
/* If the result is clearly invalid, quit */
if (framepointer == 0 || framepointer >= end || framepointer <= lastpointer)
break;
/* Otherwise try to move to the next frame base */
lastpointer = framepointer;
if ((offset = lseek(fd, bp + (long int) framepointer, 0)) == -1L || offset == 0L)
break;
}
}
/* U s a g e
*
* Usage message
*/
void usage()
{
fprintf(stderr, "Usage: %s [-dpt] [-c corefile] [-s symbfile]\n", progname);
}