postmort.c

操作系统源代码

/* postmort - post mortem dump		Author: C. W. Rose */

/* Postmort: perform post-mortem on PC Minix 1.7 core files.
 *
 * $Id$
 */

 /* 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 <limits.h>
#include <signal.h>
#include <stdlib.h>

#undef EXTERN			/* <minix/const.h> defined this */
#define EXTERN			/* so we get proc & mproc */
#include "../../kernel/const.h"
#include "../../kernel/type.h"
#include "../../kernel/proc.h"
#undef printf			/* kernel's const.h defined this */
#include "../../mm/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_SEGS];	/* segment lengths */
long int bases[NR_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_SEGS * sizeof(struct mem_map)) + sizeof(struct proc);
  for (j = 1; j < NR_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_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 */
  printf("Nonzero if blocked by busy task:	0x%04.4x\n", pt->p_int_blocked);	/* int */
  printf("Nonzero if held by busy syscall:	0x%04.4x\n", pt->p_int_held);	/* int */
#if 0
  printf("Next in chain of held-up processes:	0x%04.4x\n", pt->p_nextheld);	/* struct proc * */
#endif
  printf("P_SLOT_FREE SENDING, RECEIVING, etc.:	0x%04.4x\n", pt->p_flags);	/* int */
#if 0
  printf("Memory map:				0x%04.4x\n", pt->p_map[NR_SEGS]);	/* struct mem_map */
#endif
  printf("Process id passed in from MM:		0x%04.4x\n", pt->p_pid);	/* int */
  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("Time of next alarm in ticks or 0:	%ld\n", pt->p_alarm);	/* time_t */
#if 0
  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);	/* 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 */
  printf("Count of pending/unfinished signals:	0x%04.4x\n", pt->p_pendcount);	/* unsigned */
}


/* 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;