Merge "logd: sum liblog tag messages" (27425fd8) · Commits · e / os / android_system_core

logd/Android.mk

+1 −0

Original line number	Diff line number	Diff line
		@@ -40,6 +40,7 @@ LOCAL_SHARED_LIBRARIES := \
		# event_flag += $(call event_logtags,logd)
		# so make sure we do not regret hard-coding it as follows:
		event_flag := -DAUDITD_LOG_TAG=1003 -DCHATTY_LOG_TAG=1004
		event_flag += -DLIBLOG_LOG_TAG=1006

		LOCAL_CFLAGS := -Werror $(event_flag)

logd/LogBuffer.cpp

+83 −23

Original line number	Diff line number	Diff line
		@@ -17,6 +17,7 @@
		//#define DEBUG_CHECK_FOR_STALE_ENTRIES

		#include <ctype.h>
		#include <endian.h>
		#include <errno.h>
		#include <stdio.h>
		#include <string.h>
		@@ -126,27 +127,41 @@ LogBuffer::~LogBuffer() {
		}
		}

		static bool identical(LogBufferElement* elem, LogBufferElement* last) {
		enum match_type {
		DIFFERENT,
		SAME,
		SAME_LIBLOG
		};

		static enum match_type identical(LogBufferElement* elem, LogBufferElement* last) {
		// is it mostly identical?
		// if (!elem) return false;
		// if (!elem) return DIFFERENT;
		unsigned short lenl = elem->getMsgLen();
		if (!lenl) return false;
		// if (!last) return false;
		if (!lenl) return DIFFERENT;
		// if (!last) return DIFFERENT;
		unsigned short lenr = last->getMsgLen();
		if (!lenr) return false;
		// if (elem->getLogId() != last->getLogId()) return false;
		if (elem->getUid() != last->getUid()) return false;
		if (elem->getPid() != last->getPid()) return false;
		if (elem->getTid() != last->getTid()) return false;
		if (!lenr) return DIFFERENT;
		// if (elem->getLogId() != last->getLogId()) return DIFFERENT;
		if (elem->getUid() != last->getUid()) return DIFFERENT;
		if (elem->getPid() != last->getPid()) return DIFFERENT;
		if (elem->getTid() != last->getTid()) return DIFFERENT;

		// last is more than a minute old, stop squashing identical messages
		if (elem->getRealTime().nsec() >
		(last->getRealTime().nsec() + 60 * NS_PER_SEC)) return false;
		(last->getRealTime().nsec() + 60 * NS_PER_SEC)) return DIFFERENT;

		// Identical message
		const char* msgl = elem->getMsg();
		const char* msgr = last->getMsg();
		if ((lenl == lenr) && !fastcmp<memcmp>(msgl, msgr, lenl)) return true;
		if (lenl == lenr) {
		if (!fastcmp<memcmp>(msgl, msgr, lenl)) return SAME;
		// liblog tagged messages (content gets summed)
		if ((elem->getLogId() == LOG_ID_EVENTS) &&
		(lenl == sizeof(android_log_event_int_t)) &&
		!fastcmp<memcmp>(msgl, msgr,
		sizeof(android_log_event_int_t) - sizeof(int32_t)) &&
		(elem->getTag() == LIBLOG_LOG_TAG)) return SAME_LIBLOG;
		}

		// audit message (except sequence number) identical?
		static const char avc[] = "): avc: ";
		@@ -154,20 +169,22 @@ static bool identical(LogBufferElement* elem, LogBufferElement* last) {
		if (last->isBinary()) {
		if (fastcmp<memcmp>(msgl, msgr,
		sizeof(android_log_event_string_t) -
		sizeof(int32_t))) return false;
		sizeof(int32_t))) return DIFFERENT;
		msgl += sizeof(android_log_event_string_t);
		lenl -= sizeof(android_log_event_string_t);
		msgr += sizeof(android_log_event_string_t);
		lenr -= sizeof(android_log_event_string_t);
		}
		const char *avcl = android::strnstr(msgl, lenl, avc);
		if (!avcl) return false;
		if (!avcl) return DIFFERENT;
		lenl -= avcl - msgl;
		const char *avcr = android::strnstr(msgr, lenr, avc);
		if (!avcr) return false;
		if (!avcr) return DIFFERENT;
		lenr -= avcr - msgr;
		if (lenl != lenr) return false;
		return !fastcmp<memcmp>(avcl + strlen(avc), avcr + strlen(avc), lenl);
		if (lenl != lenr) return DIFFERENT;
		if (fastcmp<memcmp>(avcl + strlen(avc),
		avcr + strlen(avc), lenl)) return DIFFERENT;
		return SAME;
		}

		int LogBuffer::log(log_id_t log_id, log_time realtime,
		@@ -222,10 +239,10 @@ int LogBuffer::log(log_id_t log_id, log_time realtime,
		// dropped = NULL
		// currentLast = copy of last message
		// elem = incoming message
		// outgoing: (if elem == currentLast)
		// outgoing: if match != DIFFERENT
		// dropped = copy of first identical message -> State 1
		// currentLast = reference to elem
		// break: (if elem != currentLast)
		// break: if match == DIFFERENT
		// dropped = NULL -> State 0
		// delete copy of last message (incoming currentLast)
		// currentLast = copy of elem
		@@ -237,12 +254,21 @@ int LogBuffer::log(log_id_t log_id, log_time realtime,
		// currentLast = reference to last held-back incoming
		// message
		// elem = incoming message
		// outgoing: (if elem == currentLast)
		// outgoing: if match == SAME
		// delete copy of first identical message (dropped)
		// dropped = reference to last held-back incoming
		// message set to chatty count of 1 -> State 2
		// currentLast = reference to elem
		// break:
		// outgoing: if match == SAME_LIBLOG
		// dropped = copy of first identical message -> State 1
		// take sum of currentLast and elem
		// if sum overflows:
		// log currentLast
		// currentLast = reference to elem
		// else
		// delete currentLast
		// currentLast = reference to elem, sum liblog.
		// break: if match == DIFFERENT
		// delete dropped
		// dropped = NULL -> State 0
		// log reference to last held-back (currentLast)
		@@ -256,20 +282,54 @@ int LogBuffer::log(log_id_t log_id, log_time realtime,
		// message.
		// dropped = chatty message holding count
		// elem = incoming message
		// outgoing: (if elem == currentLast)
		// outgoing: if match != DIFFERENT
		// delete chatty message holding count
		// dropped = reference to last held-back incoming
		// message, set to chatty count + 1
		// currentLast = reference to elem
		// break:
		// break: if match == DIFFERENT
		// log dropped (chatty message)
		// dropped = NULL -> State 0
		// log reference to last held-back (currentLast)
		// currentLast = copy of elem
		// log elem
		//
		if (identical(elem, currentLast)) {
		enum match_type match = identical(elem, currentLast);
		if (match != DIFFERENT) {
		if (dropped) {
		// Sum up liblog tag messages?
		if ((count == 0) /* at Pass 1 */ && (match == SAME_LIBLOG)) {
		android_log_event_int_t* event =
		reinterpret_cast<android_log_event_int_t*>(
		const_cast<char*>(currentLast->getMsg()));
		//
		// To unit test, differentiate with something like:
		// event->header.tag = htole32(CHATTY_LOG_TAG);
		// here, then instead of delete currentLast below,
		// log(currentLast) to see the incremental sums form.
		//
		uint32_t swab = event->payload.data;
		unsigned long long total = htole32(swab);
		event = reinterpret_cast<android_log_event_int_t*>(
		const_cast<char*>(elem->getMsg()));
		swab = event->payload.data;

		lastLoggedElements[LOG_ID_EVENTS] = elem;
		total += htole32(swab);
		// check for overflow
		if (total >= UINT32_MAX) {
		log(currentLast);
		pthread_mutex_unlock(&mLogElementsLock);
		return len;
		}
		stats.add(currentLast);
		stats.subtract(currentLast);
		delete currentLast;
		swab = total;
		event->payload.data = htole32(swab);
		pthread_mutex_unlock(&mLogElementsLock);
		return len;
		}
		if (count == USHRT_MAX) {
		log(dropped);
		count = 1;