#!/usr/bin/stap
/*
 * Copyright (c) 2010 Oracle and/or its affiliates.  All rights reserved.
 *
 * showerror.stp - Capture context about certain DB errors.
 *
 * This shows the stack when a variant of DB->err() is called.
 * Specify the target process on the command line as
 *	-p <pid> or
 *	-c "<program> [<args>..]"
 *
 * This script does not require DWARF symbols in libdb.
 */

global errors, errorcount, maxlimit;

probe begin
{
	errorcount = 0;
	maxlimit = -1;
	%( $# >= 2 %? maxlimit = $2 %)
	printf("Display DB stack when "); 
	if (pid() == 0)
		printf("an application using %s", @1)
	else
		printf("process %d", pid());
	printf(" prints a DB internal error message: limit %d\n", maxlimit);
}

/* __db_err(ENV *, int errorcode, char *message, ...) */
probe process(@1).function("__db_err").call
{
	message = user_string(pointer_arg(3));
	printf("DB error %d message \"%s\"(%x,...) from:\n",
	    int_arg(2), message, ulong_arg(4));
	print_backtrace();
	errors[message, backtrace()] <<< 1;
	if (++errorcount == maxlimit)
		exit();
}

/* __db_errx(ENV *, char *message, ...) */
probe process(@1).function("__db_errx").call
{
	message = user_string(pointer_arg(2));
	printf("DB error message \"%s\"(%x,...) parms %s from:\n", message,
	    int_arg(3), $$parms);
	print_backtrace();
	errors[message, backtrace()] <<< 1;
	if (++errorcount == maxlimit)
		exit();
}


/* __env_panic(ENV *, int errorcode) */
probe process(@1).function("__env_panic").call
{
	printf("DB panic with error code %d from:\n", int_arg(2));
	print_backtrace();
	if (++errorcount == maxlimit)
		exit();
}