dt_subr.c

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/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only.
 * See the file usr/src/LICENSING.NOTICE in this distribution or
 * http://www.opensolaris.org/license/ for details.
 */

#pragma ident	"@(#)dt_subr.c	1.7	04/12/18 SMI"

#include <sys/sysmacros.h>
#include <strings.h>
#include <unistd.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <ctype.h>
#include <alloca.h>
#include <assert.h>
#include <dt_impl.h>

static const struct {
	size_t dtps_offset;
	size_t dtps_len;
} dtrace_probespecs[] = {
	{ offsetof(dtrace_probedesc_t, dtpd_provider),	DTRACE_PROVNAMELEN },
	{ offsetof(dtrace_probedesc_t, dtpd_mod),	DTRACE_MODNAMELEN },
	{ offsetof(dtrace_probedesc_t, dtpd_func),	DTRACE_FUNCNAMELEN },
	{ offsetof(dtrace_probedesc_t, dtpd_name),	DTRACE_NAMELEN }
};

int
dtrace_xstr2desc(dtrace_hdl_t *dtp, dtrace_probespec_t spec,
    const char *s, int argc, char *const argv[], dtrace_probedesc_t *pdp)
{
	size_t off, len, vlen;
	const char *p, *q, *v;

	char buf[32]; /* for id_t as %d (see below) */

	if (spec < DTRACE_PROBESPEC_NONE || spec > DTRACE_PROBESPEC_NAME)
		return (dt_set_errno(dtp, EINVAL));

	bzero(pdp, sizeof (dtrace_probedesc_t));
	p = s + strlen(s) - 1;

	do {
		for (len = 0; p >= s && *p != ':'; len++)
			p--; /* move backward until we find a delimiter */

		q = p + 1;
		vlen = 0;

		if ((v = strchr(q, '$')) != NULL && v < q + len) {
			/*
			 * Set vlen to the length of the variable name and then
			 * reset len to the length of the text prior to '$'. If
			 * the name begins with a digit, interpret it using the
			 * the argv[] array.  Otherwise we look in dt_macros.
			 * For the moment, all dt_macros variables are of type
			 * id_t (see dtrace_update() for more details on that).
			 */
			vlen = (size_t)(q + len - v);
			len = (size_t)(v - q);

			/*
			 * If the variable string begins with $$, skip past the
			 * leading dollar sign since $ and $$ are equivalent
			 * macro reference operators in a probe description.
			 */
			if (vlen > 2 && v[1] == '$') {
				vlen--;
				v++;
			}

			if (isdigit(v[1])) {
				char *end;
				long i;

				errno = 0;
				i = strtol(v + 1, &end, 10);

				if (i < 0 || i >= argc ||
				    errno != 0 || end != v + vlen)
					return (dt_set_errno(dtp, EDT_BADSPCV));

				v = argv[i];
				vlen = strlen(v);

				if (yypcb != NULL && yypcb->pcb_sargv == argv)
					yypcb->pcb_sflagv[i] |= DT_IDFLG_REF;

			} else if (vlen > 1) {
				char *vstr = alloca(vlen);
				dt_ident_t *idp;

				(void) strncpy(vstr, v + 1, vlen - 1);
				vstr[vlen - 1] = '\0';
				idp = dt_idhash_lookup(dtp->dt_macros, vstr);

				if (idp == NULL)
					return (dt_set_errno(dtp, EDT_BADSPCV));

				v = buf;
				vlen = snprintf(buf, 32, "%d", idp->di_id);

			} else
				return (dt_set_errno(dtp, EDT_BADSPCV));
		}

		if (spec == DTRACE_PROBESPEC_NONE)
			return (dt_set_errno(dtp, EDT_BADSPEC));

		if (len + vlen >= dtrace_probespecs[spec].dtps_len)
			return (dt_set_errno(dtp, ENAMETOOLONG));

		off = dtrace_probespecs[spec--].dtps_offset;
		bcopy(q, (char *)pdp + off, len);
		bcopy(v, (char *)pdp + off + len, vlen);

	} while (--p >= s);

	return (0);
}

int
dtrace_str2desc(dtrace_hdl_t *dtp, dtrace_probespec_t spec,
    const char *s, dtrace_probedesc_t *pdp)
{
	return (dtrace_xstr2desc(dtp, spec, s, 0, NULL, pdp));
}

int
dtrace_id2desc(dtrace_hdl_t *dtp, dtrace_id_t id, dtrace_probedesc_t *pdp)
{
	bzero(pdp, sizeof (dtrace_probedesc_t));
	pdp->dtpd_id = id;

	if (dt_ioctl(dtp, DTRACEIOC_PROBES, pdp) == -1 ||
	    pdp->dtpd_id != id)
		return (dt_set_errno(dtp, EDT_BADID));

	return (0);
}

char *
dtrace_desc2str(const dtrace_probedesc_t *pdp, char *buf, size_t len)
{
	if (pdp->dtpd_id == 0) {
		(void) snprintf(buf, len, "%s:%s:%s:%s", pdp->dtpd_provider,
		    pdp->dtpd_mod, pdp->dtpd_func, pdp->dtpd_name);
	} else
		(void) snprintf(buf, len, "%u", pdp->dtpd_id);

	return (buf);
}

char *
dtrace_attr2str(dtrace_attribute_t attr, char *buf, size_t len)
{
	const char *name = dtrace_stability_name(attr.dtat_name);
	const char *data = dtrace_stability_name(attr.dtat_data);
	const char *class = dtrace_class_name(attr.dtat_class);

	if (name == NULL || data == NULL || class == NULL)
		return (NULL); /* one or more invalid attributes */

	(void) snprintf(buf, len, "%s/%s/%s", name, data, class);
	return (buf);
}

static char *
dt_getstrattr(char *p, char **qp)
{
	char *q;

	if (*p == '\0')
		return (NULL);

	if ((q = strchr(p, '/')) == NULL)
		q = p + strlen(p);
	else
		*q++ = '\0';

	*qp = q;
	return (p);
}

int
dtrace_str2attr(const char *str, dtrace_attribute_t *attr)
{
	dtrace_stability_t s;
	dtrace_class_t c;
	char *p, *q;

	if (str == NULL || attr == NULL)
		return (-1); /* invalid function arguments */

	*attr = _dtrace_maxattr;
	p = alloca(strlen(str) + 1);
	(void) strcpy(p, str);

	if ((p = dt_getstrattr(p, &q)) == NULL)
		return (0);

	for (s = 0; s <= DTRACE_STABILITY_MAX; s++) {
		if (strcasecmp(p, dtrace_stability_name(s)) == 0) {
			attr->dtat_name = s;
			break;
		}
	}

	if (s > DTRACE_STABILITY_MAX)
		return (-1);

	if ((p = dt_getstrattr(q, &q)) == NULL)
		return (0);

	for (s = 0; s <= DTRACE_STABILITY_MAX; s++) {
		if (strcasecmp(p, dtrace_stability_name(s)) == 0) {
			attr->dtat_data = s;
			break;
		}
	}

	if (s > DTRACE_STABILITY_MAX)
		return (-1);

	if ((p = dt_getstrattr(q, &q)) == NULL)
		return (0);

	for (c = 0; c <= DTRACE_CLASS_MAX; c++) {
		if (strcasecmp(p, dtrace_class_name(c)) == 0) {
			attr->dtat_class = c;
			break;
		}
	}

	if (c > DTRACE_CLASS_MAX || (p = dt_getstrattr(q, &q)) != NULL)
		return (-1);

	return (0);
}

const char *
dtrace_stability_name(dtrace_stability_t s)
{
	switch (s) {
	case DTRACE_STABILITY_INTERNAL:	return ("Internal");
	case DTRACE_STABILITY_PRIVATE:	return ("Private");
	case DTRACE_STABILITY_OBSOLETE:	return ("Obsolete");
	case DTRACE_STABILITY_EXTERNAL:	return ("External");
	case DTRACE_STABILITY_UNSTABLE:	return ("Unstable");
	case DTRACE_STABILITY_EVOLVING:	return ("Evolving");
	case DTRACE_STABILITY_STABLE:	return ("Stable");
	case DTRACE_STABILITY_STANDARD:	return ("Standard");
	default:			return (NULL);
	}
}

const char *
dtrace_class_name(dtrace_class_t c)
{
	switch (c) {
	case DTRACE_CLASS_UNKNOWN:	return ("Unknown");
	case DTRACE_CLASS_CPU:		return ("CPU");
	case DTRACE_CLASS_PLATFORM:	return ("Platform");
	case DTRACE_CLASS_GROUP:	return ("Group");
	case DTRACE_CLASS_ISA:		return ("ISA");
	case DTRACE_CLASS_COMMON:	return ("Common");
	default:			return (NULL);
	}
}

dtrace_attribute_t
dt_attr_min(dtrace_attribute_t a1, dtrace_attribute_t a2)
{
	dtrace_attribute_t am;

	am.dtat_name = MIN(a1.dtat_name, a2.dtat_name);
	am.dtat_data = MIN(a1.dtat_data, a2.dtat_data);
	am.dtat_class = MIN(a1.dtat_class, a2.dtat_class);

	return (am);
}

dtrace_attribute_t
dt_attr_max(dtrace_attribute_t a1, dtrace_attribute_t a2)
{
	dtrace_attribute_t am;

	am.dtat_name = MAX(a1.dtat_name, a2.dtat_name);
	am.dtat_data = MAX(a1.dtat_data, a2.dtat_data);
	am.dtat_class = MAX(a1.dtat_class, a2.dtat_class);

	return (am);
}

/*
 * Compare two attributes and return an integer value in the following ranges:
 *
 * <0 if any of a1's attributes are less than a2's attributes
 * =0 if all of a1's attributes are equal to a2's attributes
 * >0 if all of a1's attributes are greater than or equal to a2's attributes
 *
 * To implement this function efficiently, we subtract a2's attributes from
 * a1's to obtain a negative result if an a1 attribute is less than its a2
 * counterpart.  We then OR the intermediate results together, relying on the
 * twos-complement property that if any result is negative, the bitwise union
 * will also be negative since the highest bit will be set in the result.
 */
int
dt_attr_cmp(dtrace_attribute_t a1, dtrace_attribute_t a2)
{
	return (((int)a1.dtat_name - a2.dtat_name) |
	    ((int)a1.dtat_data - a2.dtat_data) |
	    ((int)a1.dtat_class - a2.dtat_class));
}

char *
dt_attr_str(dtrace_attribute_t a, char *buf, size_t len)
{
	static const char stability[] = "ipoxuesS";
	static const char class[] = "uCpgIc";

	if (a.dtat_name < sizeof (stability) &&
	    a.dtat_data < sizeof (stability) && a.dtat_class < sizeof (class)) {
		(void) snprintf(buf, len, "[%c/%c/%c]", stability[a.dtat_name],
		    stability[a.dtat_data], class[a.dtat_class]);
	} else {
		(void) snprintf(buf, len, "[%u/%u/%u]",
		    a.dtat_name, a.dtat_data, a.dtat_class);
	}

	return (buf);
}

char *
dt_version_num2str(dt_version_t v, char *buf, size_t len)
{
	uint_t M = DT_VERSION_MAJOR(v);
	uint_t m = DT_VERSION_MINOR(v);
	uint_t u = DT_VERSION_MICRO(v);

	if (u == 0)
		(void) snprintf(buf, len, "%u.%u", M, m);
	else
		(void) snprintf(buf, len, "%u.%u.%u", M, m, u);

	return (buf);
}

int
dt_version_str2num(const char *s, dt_version_t *vp)
{
	int i = 0, n[3] = { 0, 0, 0 };
	char c;

	while ((c = *s++) != '\0') {
		if (isdigit(c))
			n[i] = n[i] * 10 + c - '0';
		else if (c != '.' || i++ >= sizeof (n) / sizeof (n[0]) - 1)