monitor.c

/*

 This code was written as part of the CMU Common Lisp project at
 Carnegie Mellon University, and has been placed in the public domain.

*/

#include <stdio.h>
#include <sys/types.h>
#include <stdlib.h>
#include <setjmp.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <signal.h>
#include <string.h>

#include "lisp.h"
#include "internals.h"
#include "globals.h"
#include "vars.h"
#include "parse.h"
#include "os.h"
#include "interrupt.h"
#include "lispregs.h"
#include "monitor.h"
#include "print.h"
#include "arch.h"
#include "gc.h"
#include "search.h"
#include "purify.h"
#if defined GENCGC
#include "gencgc.h"
#endif

extern boolean isatty(int fd);

typedef void cmd(char **ptr);

static cmd call_cmd, dump_cmd, print_cmd, quit, help;
static cmd flush_cmd, search_cmd, regs_cmd, exit_cmd;
static cmd gc_cmd, print_context_cmd;
static cmd backtrace_cmd, purify_cmd, catchers_cmd;
static cmd grab_sigs_cmd;

static struct cmd {
    char *cmd, *help;
    void (*fn) (char **ptr);
} Cmds[] = {
    /* *INDENT-OFF* */
    {"help", "Display this info", help},
    {"?", NULL, help},
    {"backtrace", "backtrace up to N frames", backtrace_cmd},
    {"call", "call FUNCTION with ARG1, ARG2, ...", call_cmd},
    {"catchers", "Print a list of all the active catchers.", catchers_cmd},
    {"context", "print interrupt context number I.", print_context_cmd},
    {"dump", "dump memory starting at ADDRESS for COUNT words.", dump_cmd},
    {"d", NULL, dump_cmd},
    {"exit", "Exit this instance of the monitor.", exit_cmd},
    {"flush", "flush all temp variables.", flush_cmd},
    {"gc", "collect garbage (caveat collector).", gc_cmd},
    {"grab-signals", "Set the signal handlers to call LDB.", grab_sigs_cmd},
    {"purify", "purify (caveat purifier).", purify_cmd},
    {"print", "print object at ADDRESS.", print_cmd},
    {"p", NULL, print_cmd},
    {"quit", "quit.", quit},
    {"regs", "display current lisp regs.", regs_cmd},
    {"search", "search for TYPE starting at ADDRESS for a max of COUNT words.", search_cmd},
    {"s", NULL, search_cmd},
    {NULL, NULL, NULL}
    /* *INDENT-ON* */
};


static jmp_buf curbuf;


static int
visable(unsigned char c)
{
    if (c < ' ' || c > '~')
	return ' ';
    else
	return c;
}

static void
dump_cmd(char **ptr)
{
    static char *lastaddr = 0;
    static int lastcount = 20;

    char *addr = lastaddr;
    int count = lastcount, displacement;

    if (more_p(ptr)) {
	addr = parse_addr(ptr);

	if (more_p(ptr))
	    count = parse_number(ptr);
    }

    if (count == 0) {
	printf("COUNT must be non-zero.\n");
	return;
    }

    lastcount = count;

    if (count > 0)
	displacement = 4;
    else {
	displacement = -4;
	count = -count;
    }

    while (count-- > 0) {
#ifndef alpha
	printf("0x%08lX: ", (unsigned long) addr);
#else
	printf("0x%08X: ", (u32) addr);
#endif
	if (valid_addr((os_vm_address_t) addr)) {
#ifndef alpha
	    unsigned long *lptr = (unsigned long *) addr;
#else
	    u32 *lptr = (unsigned long *) addr;
#endif
	    unsigned short *sptr = (unsigned short *) addr;
	    unsigned char *cptr = (unsigned char *) addr;

	    printf
		("0x%08lx   0x%04x 0x%04x   0x%02x 0x%02x 0x%02x 0x%02x    %c%c%c%c\n",
		 lptr[0], sptr[0], sptr[1], cptr[0], cptr[1], cptr[2], cptr[3],
		 visable(cptr[0]), visable(cptr[1]), visable(cptr[2]),
		 visable(cptr[3]));
	} else
	    printf("invalid address\n");

	addr += displacement;
    }

    lastaddr = addr;
}

static void
print_cmd(char **ptr)
{
    lispobj obj = parse_lispobj(ptr);

    print(obj);
}

static void
regs_cmd(char **ptr)
{
    printf("CSP\t=\t0x%08lX\n", (unsigned long) current_control_stack_pointer);
    printf("FP\t=\t0x%08lX\n", (unsigned long) current_control_frame_pointer);
#if !defined(ibmrt) && !defined(i386) && !defined(__x86_64)
    printf("BSP\t=\t0x%08lX\n", (unsigned long) current_binding_stack_pointer);
#endif
#if defined(i386) || defined(__x86_64)
    printf("BSP\t=\t0x%08lX\n", SymbolValue(BINDING_STACK_POINTER));
#endif

    printf("DYNAMIC\t=\t0x%08lX\n", (unsigned long) current_dynamic_space);
#if defined(ibmrt) || defined(i386) || defined(__x86_64)
    printf("ALLOC\t=\t0x%08lX\n", SymbolValue(ALLOCATION_POINTER));
    printf("TRIGGER\t=\t0x%08lX\n", SymbolValue(INTERNAL_GC_TRIGGER));
#else
    printf("ALLOC\t=\t0x%08lX\n",
	   (unsigned long) current_dynamic_space_free_pointer);
    printf("TRIGGER\t=\t0x%08lX\n", (unsigned long) current_auto_gc_trigger);
#endif
    printf("STATIC\t=\t0x%08lX\n", SymbolValue(STATIC_SPACE_FREE_POINTER));
    printf("RDONLY\t=\t0x%08lX\n", SymbolValue(READ_ONLY_SPACE_FREE_POINTER));

#ifdef MIPS
    printf("FLAGS\t=\t0x%08x\n", current_flags_register);
#endif
}

static void
search_cmd(char **ptr)
{
    static int lastval = 0, lastcount = 0;
    static lispobj *start = 0, *end = 0;
    int val, count;
    lispobj *addr, obj;

    if (more_p(ptr)) {
	val = parse_number(ptr);
	if (val < 0 || val > 0xff) {
	    printf("Can only search for single bytes.\n");
	    return;
	}
	if (more_p(ptr)) {
	    addr = (lispobj *) PTR((long) parse_addr(ptr));
	    if (more_p(ptr)) {
		count = parse_number(ptr);
	    } else {
		/* Speced value and address, but no count. Only one. */
		count = -1;
	    }
	} else {
	    /* Speced a value, but no address, so search same range. */
	    addr = start;
	    count = lastcount;
	}
    } else {
	/* Speced nothing, search again for val. */
	val = lastval;
	addr = end;
	count = lastcount;
    }

    lastval = val;
    start = end = addr;
    lastcount = count;

    printf("searching for 0x%x at 0x%08lX\n", val, (unsigned long) end);

    while (search_for_type(val, &end, &count)) {
	printf("found 0x%x at 0x%08lX:\n", val, (unsigned long) end);
	obj = *end;
	addr = end;
	end += 2;
	if (TypeOf(obj) == type_FunctionHeader)
	    print((long) addr | type_FunctionPointer);
	else if (LowtagOf(obj) == type_OtherImmediate0
		 || LowtagOf(obj) ==
		 type_OtherImmediate1) print((lispobj) addr |
					     type_OtherPointer);
	else
	    print((lispobj) addr);
	if (count == -1)
	    return;
    }
}

static void
call_cmd(char **ptr)
{
    lispobj thing = parse_lispobj(ptr);
    lispobj function, cons, args[3];
    lispobj result = NIL;

    int numargs;

    if (LowtagOf(thing) == type_OtherPointer) {
	switch (TypeOf(*(lispobj *) (thing - type_OtherPointer))) {
	  case type_SymbolHeader:
	      for (cons = SymbolValue(INITIAL_FDEFN_OBJECTS);
		   cons != NIL; cons = CONS(cons)->cdr) {
		  if (FDEFN(CONS(cons)->car)->name == thing) {
		      thing = CONS(cons)->car;
		      goto fdefn;
		  }
	      }
	      printf("symbol 0x%08lx is undefined.\n", thing);
	      return;

	  case type_Fdefn:
	    fdefn:
	      function = FDEFN(thing)->function;
	      if (function == NIL) {
		  printf("fdefn 0x%08lx is undefined.\n", thing);
		  return;
	      }
	      break;
	  default:
	      printf
		  ("0x%08lx is not a function pointer, symbol, or fdefn object.\n",
		   thing);
	      return;
	}
    } else if (LowtagOf(thing) != type_FunctionPointer) {
	printf("0x%08lx is not a function pointer, symbol, or fdefn object.\n",
	       thing);
	return;
    } else
	function = thing;

    numargs = 0;
    while (more_p(ptr)) {
	if (numargs >= 3) {
	    printf("Too many arguments.  3 at most.\n");
	    return;
	}
	args[numargs++] = parse_lispobj(ptr);
    }

    switch (numargs) {
      case 0:
	  result = funcall0(function);
	  break;
      case 1:
	  result = funcall1(function, args[0]);
	  break;
      case 2:
	  result = funcall2(function, args[0], args[1]);
	  break;
      case 3:
	  result = funcall3(function, args[0], args[1], args[2]);
	  break;
    }

    print(result);
}

static void
flush_cmd(char **ptr)
{
    flush_vars();
}

static void
quit(char **ptr)
{
    char buf[10];
    char *result; 

    printf("Really quit? [y] ");
    fflush(stdout);
    result = fgets(buf, sizeof(buf), stdin);
    if (result && (buf[0] == 'y' || buf[0] == 'Y' || buf[0] == '\n')) {
	exit(0);
    }
}

static void
help(char **ptr)
{
    struct cmd *cmd;

    for (cmd = Cmds; cmd->cmd != NULL; cmd++)
	if (cmd->help != NULL)
	    printf("%s\t%s\n", cmd->cmd, cmd->help);
}

static int done;

static void
exit_cmd(char **ptr)
{
    done = TRUE;
}

static void
gc_cmd(char **ptr)
{
    collect_garbage();
}

static void
purify_cmd(char **ptr)
{
    purify(NIL, NIL);
}

static void
print_context(os_context_t * context)
{
    int i;

    for (i = 0; i < NREGS; i++) {
	printf("%s:\t", lisp_register_names[i]);
#if defined(i386) || defined(__x86_64)
	brief_print((lispobj) SC_REG(context, i * 2));
#else
	brief_print((lispobj) SC_REG(context, i));
#endif
    }
    printf("PC:\t\t  0x%08lx\n", (unsigned long) SC_PC(context));
}

static void
print_context_cmd(char **ptr)
{
    int free;

    free = SymbolValue(FREE_INTERRUPT_CONTEXT_INDEX) >> 2;

    if (more_p(ptr)) {
	int index;

	index = parse_number(ptr);

	if ((index >= 0) && (index < free)) {
	    printf("There are %d interrupt contexts.\n", free);
	    printf("Printing context %d\n", index);
	    print_context(lisp_interrupt_contexts[index]);
	} else {
	    printf("There aren't that many/few contexts.\n");
	    printf("There are %d interrupt contexts.\n", free);
	}
    } else {
	if (free == 0)
	    printf("There are no interrupt contexts!\n");
	else {
	    printf("There are %d interrupt contexts.\n", free);
	    printf("Printing context %d\n", free - 1);
	    print_context(lisp_interrupt_contexts[free - 1]);
	}
    }
}

static void
backtrace_cmd(char **ptr)
{
    void backtrace(int frames);
    int n;

    if (more_p(ptr))
	n = parse_number(ptr);
    else
	n = 100;

    printf("Backtrace:\n");
    backtrace(n);
}

static void
catchers_cmd(char **ptr)
{
    struct catch_block *catch;

    catch = (struct catch_block *) SymbolValue(CURRENT_CATCH_BLOCK);

    if (catch == NULL)
	printf("There are no active catchers!\n");
    else {
	while (catch != NULL) {
#if !(defined(i386) || defined(__x86_64))
	    printf
		("0x%08lX:\n\tuwp: 0x%08lX\n\tfp: 0x%08lX\n\tcode: 0x%08lx\n\tentry: 0x%08lx\n\ttag: ",
		 (unsigned long) catch, (unsigned long) (catch->current_uwp),
		 (unsigned long) (catch->current_cont), catch->current_code,
		 catch->entry_pc);
#else
	    printf
		("0x%08lX:\n\tuwp: 0x%08lX\n\tfp: 0x%08lX\n\tcode: 0x%p\n\tentry: 0x%08lx\n\ttag: ",
		 (unsigned long) catch, (unsigned long) (catch->current_uwp),
		 (unsigned long) (catch->current_cont),
		 component_ptr_from_pc((lispobj *) catch->entry_pc) +
		 type_OtherPointer, catch->entry_pc);
#endif
	    brief_print((lispobj) catch->tag);
	    catch = catch->previous_catch;
	}
    }
}

static void
grab_sigs_cmd(char **ptr)
{
    extern void sigint_init(void);

    printf("Grabbing signals.\n");
    sigint_init();
}

static void
sub_monitor(void)
{
    struct cmd *cmd, *found;
    char buf[256];
    char *line, *ptr, *token;
    int ambig;

    while (!done) {
	printf("ldb> ");
	fflush(stdout);
	line = fgets(buf, sizeof(buf), stdin);
	if (line == NULL) {
	    if (isatty(0)) {
		putchar('\n');
                /*
                    * We can no longer read anything from stdin, so
                    * just exit this loop instead of spewing an
                    * endless stream of prompts.  This also means we
                    * can't use ldb anymore because stdin is
                    * unreadable.
                    */
                break;
	    } else {
		fprintf(stderr, "\nEOF on something other than a tty.\n");
		exit(1);
	    }
	}
	ptr = line;
	if ((token = parse_token(&ptr)) == NULL)
	    continue;
	ambig = 0;
	found = NULL;
	for (cmd = Cmds; cmd->cmd != NULL; cmd++) {
	    if (strcmp(token, cmd->cmd) == 0) {
		found = cmd;
		ambig = 0;
		break;
	    } else if (strncmp(token, cmd->cmd, strlen(token)) == 0) {
		if (found)
		    ambig = 1;
		else
		    found = cmd;
	    }
	}
	if (ambig)
	    printf("``%s'' is ambiguous.\n", token);
	else if (found == NULL)
	    printf("unknown command: ``%s''\n", token);
	else {
	    reset_printer();
	    (*found->fn) (&ptr);
	}
    }
}

void
ldb_monitor(void)
{
    jmp_buf oldbuf;

    memcpy(oldbuf, curbuf, sizeof(jmp_buf));

    printf("LDB monitor\n");

    setjmp(curbuf);

    sub_monitor();

    done = FALSE;

    memcpy(curbuf, oldbuf, sizeof(jmp_buf));
}

void
throw_to_monitor(void)
{
    longjmp(curbuf, 1);
}