// context-symbols tapset
// Copyright (C) 2005-2008 Red Hat Inc.
// Copyright (C) 2006 Intel Corporation.
//
// This file is part of systemtap, and is free software.  You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.
// <tapsetdescription>
// Context functions provide additional information about where an event occurred. These functions can 
//provide information such as a backtrace to where the event occured and the current register values for the 
//processor.
// </tapsetdescription>
%{
#ifndef STP_NEED_SYMBOL_DATA
#define STP_NEED_SYMBOL_DATA 1
#endif
%}
// weirdness with print_stack, argument appears in build as undescribed
/**
 * sfunction print_stack - Print out stack from string.
 * @stk: String with list of hexidecimal addresses. (FIXME)
 *
 *  Perform a symbolic lookup of the addresses in the given  string,
 *  which is assumed to be the result of a prior call to 
 *  <command>backtrace()</command>.
 * 
 *  Print one line per address, including the address, the
 *  name  of the function containing the address, and an estimate of
 *  its position within that function.  Return nothing.
 */
function print_stack(stk:string) %{
	char *ptr = THIS->stk;
	char *tok = strsep(&ptr, " ");
	while (tok && *tok) {
		_stp_print_char(' ');
		_stp_symbol_print (simple_strtol(tok, NULL, 16));
		_stp_print_char('\n');
		tok = strsep(&ptr, " ");
	}
%}

/**
 * sfunction probefunc - Return the probe point's function name, if known.
 */
function probefunc:string () %{ /* pure */
	char *ptr, *start;

	start = strstr(CONTEXT->probe_point, "function(\"");
	ptr = start + 10; 
	if (!start) {
		start = strstr(CONTEXT->probe_point, "inline(\"");
		ptr = start + 8;
	}

	if (start) {
		int len = MAXSTRINGLEN;
		char *dst = THIS->__retvalue;
		while (*ptr != '@' && --len > 0 && *ptr)
			*dst++ = *ptr++;
		*dst = 0;

	} else if (CONTEXT->regs &&
#if defined (__ia64__)
		((unsigned long)REG_IP(CONTEXT->regs) >= (unsigned long)KERNEL_START)) {
#else
		((unsigned long)REG_IP(CONTEXT->regs) >= (unsigned long)PAGE_OFFSET)) {
#endif
		_stp_symbol_snprint(THIS->__retvalue, MAXSTRINGLEN, REG_IP(CONTEXT->regs));
       	         if (THIS->__retvalue[0] == '.')  /* powerpc symbol has a dot*/
       	         	strlcpy(THIS->__retvalue,THIS->__retvalue + 1,MAXSTRINGLEN);
	} else {
		THIS->__retvalue[0] = '\0';
	}
%}

/**
 * sfunction probemod - Return the probe point's module name, if known.
 */
function probemod:string () %{ /* pure */
	char *ptr, *start;

	start = strstr(CONTEXT->probe_point, "module(\"");
	ptr = start + 8;

	if (start) {
		int len = MAXSTRINGLEN;
		char *dst = THIS->__retvalue;
		while (*ptr != '"' && --len && *ptr)
			*dst++ = *ptr++;
		*dst = 0;
	} else {
		/* XXX: need a PC- and symbol-table-based fallback. */
		THIS->__retvalue[0] = '\0';
	}
%}