trace.c

DHCP服务器源码

/* trace.c

   Subroutines that support tracing of OMAPI wire transactions and
   provide a mechanism for programs using OMAPI to trace their own
   transactions... */

/*
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * Copyright (c) 2001-2003 by Internet Software Consortium
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 *   Internet Systems Consortium, Inc.
 *   950 Charter Street
 *   Redwood City, CA 94063
 *   <[e-mail]>
 *   http://www.isc.org/
 *
 * This software has been written for Internet Systems Consortium
 * by Ted Lemon, as part of a project for Nominum, Inc.   To learn more
 * about Internet Systems Consortium, see http://www.isc.org/.  To
 * learn more about Nominum, Inc., see ``http://www.nominum.com''.
 */

#include <omapip/omapip_p.h>

#if defined (TRACING)
void (*trace_set_time_hook) (u_int32_t);
static int tracing_stopped;
static int traceoutfile;
static int traceindex;
static trace_type_t **trace_types;
static int trace_type_count;
static int trace_type_max;
static trace_type_t *new_trace_types;
static FILE *traceinfile;
static tracefile_header_t tracefile_header;
static int trace_playback_flag;
trace_type_t trace_time_marker;

#if defined (DEBUG_MEMORY_LEAKAGE) || defined (DEBUG_MEMORY_LEAKAGE_ON_EXIT)
extern omapi_array_t *trace_listeners;
extern omapi_array_t *omapi_connections;

void trace_free_all ()
{
	trace_type_t *tp;
	int i;
	tp = new_trace_types;
	while (tp) {
		new_trace_types = tp -> next;
		if (tp -> name) {
			dfree (tp -> name, MDL);
			tp -> name = (char *)0;
		}
		dfree (tp, MDL);
		tp = new_trace_types;
	}
	for (i = 0; i < trace_type_count; i++) {
		if (trace_types [i]) {
			if (trace_types [i] -> name)
				dfree (trace_types [i] -> name, MDL);
			dfree (trace_types [i], MDL);
		}
	}
	dfree (trace_types, MDL);
	trace_types = (trace_type_t **)0;
	trace_type_count = trace_type_max = 0;

	omapi_array_free (&trace_listeners, MDL);
	omapi_array_free (&omapi_connections, MDL);
}
#endif

static isc_result_t trace_type_record (trace_type_t *,
				       unsigned, const char *, int);

int trace_playback ()
{
	return trace_playback_flag;
}

int trace_record ()
{
	if (traceoutfile && !tracing_stopped)
		return 1;
	return 0;
}

isc_result_t trace_init (void (*set_time) (u_int32_t),
			 const char *file, int line)
{
	trace_type_t *root_type;
	static int root_setup = 0;

	if (root_setup)
		return ISC_R_SUCCESS;

	trace_set_time_hook = set_time;

	root_type = trace_type_register ("trace-index-mapping",
					 (void *)0, trace_index_map_input,
					 trace_index_stop_tracing, file, line);
	if (!root_type)
		return ISC_R_UNEXPECTED;
	if (new_trace_types == root_type)
		new_trace_types = new_trace_types -> next;
	root_type -> index = 0;
	trace_type_stash (root_type);

	root_setup = 1;
	return ISC_R_SUCCESS;
}

isc_result_t trace_begin (const char *filename,
			  const char *file, int line)
{
	tracefile_header_t tfh;
	int status;
	trace_type_t *tptr, *next;
	isc_result_t result;

	if (traceoutfile) {
		log_error ("%s(%d): trace_begin called twice",
			   file, line);
		return ISC_R_INVALIDARG;
	}

	traceoutfile = open (filename, O_CREAT | O_WRONLY | O_EXCL, 0644);
	if (traceoutfile < 0) {
		log_error ("%s(%d): trace_begin: %s: %m",
			   file, line, filename);
		return ISC_R_UNEXPECTED;
	}
#if defined (HAVE_SETFD)
	if (fcntl (traceoutfile, F_SETFD, 1) < 0)
		log_error ("Can't set close-on-exec on %s: %m", filename);
#endif

	tfh.magic = htonl (TRACEFILE_MAGIC);
	tfh.version = htonl (TRACEFILE_VERSION);
	tfh.hlen = htonl (sizeof (tracefile_header_t));
	tfh.phlen = htonl (sizeof (tracepacket_t));
	
	status = write (traceoutfile, &tfh, sizeof tfh);
	if (status < 0) {
		log_error ("%s(%d): trace_begin write failed: %m", file, line);
		return ISC_R_UNEXPECTED;
	} else if (status != sizeof tfh) {
		log_error ("%s(%d): trace_begin: short write (%d:%ld)",
			   file, line, status, (long)(sizeof tfh));
		trace_stop ();
		return ISC_R_UNEXPECTED;
	}

	/* Stash all the types that have already been set up. */
	if (new_trace_types) {
		next = new_trace_types;
		new_trace_types = (trace_type_t *)0;
		for (tptr = next; tptr; tptr = next) {
			next = tptr -> next;
			if (tptr -> index != 0) {
				result = (trace_type_record
					  (tptr,
					   strlen (tptr -> name), file, line));
				if (result != ISC_R_SUCCESS)
					return status;
			}
		}
	}
	
	return ISC_R_SUCCESS;
}

isc_result_t trace_write_packet (trace_type_t *ttype, unsigned length,
				 const char *buf, const char *file, int line)
{
	trace_iov_t iov;

	iov.buf = buf;
	iov.len = length;
	return trace_write_packet_iov (ttype, 1, &iov, file, line);
}

isc_result_t trace_write_packet_iov (trace_type_t *ttype,
				     int count, trace_iov_t *iov,
				     const char *file, int line)
{
	tracepacket_t tmp;
	int status;
	int i;
	int length;

	/* Really shouldn't get called here, but it may be hard to turn off
	   tracing midstream if the trace file write fails or something. */
	if (tracing_stopped)
		return 0;

	if (!ttype) {
		log_error ("%s(%d): trace_write_packet with null trace type",
			   file ? file : "<unknown file>", line);
		return ISC_R_INVALIDARG;
	}
	if (!traceoutfile) {
		log_error ("%s(%d): trace_write_packet with no tracefile.",
			   file ? file : "<unknown file>", line);
		return ISC_R_INVALIDARG;
	}
	
	/* Compute the total length of the iov. */
	length = 0;
	for (i = 0; i < count; i++)
		length += iov [i].len;

	/* We have to swap out the data, because it may be read back on a
	   machine of different endianness. */
	tmp.type_index = htonl (ttype -> index);
	tmp.when = htonl (time ((time_t *)0)); /* XXX */
	tmp.length = htonl (length);

	status = write (traceoutfile, &tmp, sizeof tmp);
	if (status < 0) {
		log_error ("%s(%d): trace_write_packet write failed: %m",
			   file, line);
		return ISC_R_UNEXPECTED;
	} else if (status != sizeof tmp) {
		log_error ("%s(%d): trace_write_packet: short write (%d:%ld)",
			   file, line, status, (long)(sizeof tmp));
		trace_stop ();
	}

	for (i = 0; i < count; i++) {
		status = write (traceoutfile, iov [i].buf, iov [i].len);
		if (status < 0) {
			log_error ("%s(%d): %s write failed: %m",
				   file, line, "trace_write_packet");
			return ISC_R_UNEXPECTED;
		} else if (status != iov [i].len) {
			log_error ("%s(%d): %s: short write (%d:%d)",
				   file, line,
				   "trace_write_packet", status, length);
			trace_stop ();
		}
	}

	/* Write padding on the end of the packet to align the next
	   packet to an 8-byte boundary.   This is in case we decide to
	   use mmap in some clever way later on. */
	if (length % 8) {
	    static char zero [] = { 0, 0, 0, 0, 0, 0, 0 };
	    unsigned padl = 8 - (length % 8);
		
	    status = write (traceoutfile, zero, padl);
	    if (status < 0) {
		log_error ("%s(%d): trace_write_packet write failed: %m",
			   file, line);
		return ISC_R_UNEXPECTED;
	    } else if (status != padl) {
		log_error ("%s(%d): trace_write_packet: short write (%d:%d)",
			   file, line, status, padl);
		trace_stop ();
	    }
	}

	return ISC_R_SUCCESS;
}

void trace_type_stash (trace_type_t *tptr)
{
	trace_type_t **vec;
	int delta;
	if (trace_type_max <= tptr -> index) {
		delta = tptr -> index - trace_type_max + 10;
		vec = dmalloc (((trace_type_max + delta) *
				sizeof (trace_type_t *)), MDL);
		if (!vec)
			return;
		memset (&vec [trace_type_max], 0,
			(sizeof (trace_type_t *)) * delta);
		trace_type_max += delta;
		if (trace_types) {
		    memcpy (vec, trace_types,
			    trace_type_count * sizeof (trace_type_t *));
		    dfree (trace_types, MDL);
		}
		trace_types = vec;
	}
	trace_types [tptr -> index] = tptr;
	if (tptr -> index >= trace_type_count)
		trace_type_count = tptr -> index + 1;
}

trace_type_t *trace_type_register (const char *name,
				   void *baggage,
				   void (*have_packet) (trace_type_t *,
							unsigned, char *),
				   void (*stop_tracing) (trace_type_t *),
				   const char *file, int line)
{
	trace_type_t *ttmp, *tptr;
	unsigned slen = strlen (name);
	isc_result_t status;

	ttmp = dmalloc (sizeof *ttmp, file, line);
	if (!ttmp)
		return ttmp;
	ttmp -> index = -1;
	ttmp -> name = dmalloc (slen + 1, file, line);
	if (!ttmp -> name) {
		dfree (ttmp, file, line);
		return (trace_type_t *)0;
	}
	strcpy (ttmp -> name, name);
	ttmp -> have_packet = have_packet;
	ttmp -> stop_tracing = stop_tracing;
	
	if (traceoutfile) {
		status = trace_type_record (ttmp, slen, file, line);
		if (status != ISC_R_SUCCESS) {
			dfree (ttmp -> name, file, line);
			dfree (ttmp, file, line);
			return (trace_type_t *)0;
		}
	} else {
		ttmp -> next = new_trace_types;
		new_trace_types = ttmp;
	}

	return ttmp;
}
						   
static isc_result_t trace_type_record (trace_type_t *ttmp, unsigned slen,
				       const char *file, int line)
{
	trace_index_mapping_t *tim;
	isc_result_t status;

	tim = dmalloc (slen + TRACE_INDEX_MAPPING_SIZE, file, line);
	if (!tim)
		return ISC_R_NOMEMORY;
	ttmp -> index = ++traceindex;
	trace_type_stash (ttmp);
	tim -> index = htonl (ttmp -> index);
	memcpy (tim -> name, ttmp -> name, slen);
	status = trace_write_packet (trace_types [0],