Merge "logd: Allow setDropped() to be called on already dropped messages"
diff --git a/logd/LogBufferElement.cpp b/logd/LogBufferElement.cpp
index 2fd9f95..82c4fb9 100644
--- a/logd/LogBufferElement.cpp
+++ b/logd/LogBufferElement.cpp
@@ -56,14 +56,7 @@
mLogId(elem.mLogId),
mDropped(elem.mDropped) {
if (mDropped) {
- if (elem.isBinary() && elem.mMsg != nullptr) {
- // for the following "len" value, refer to : setDropped(uint16_t value), getTag()
- const int len = sizeof(android_event_header_t);
- mMsg = new char[len];
- memcpy(mMsg, elem.mMsg, len);
- } else {
- mMsg = nullptr;
- }
+ mTag = elem.getTag();
} else {
mMsg = new char[mMsgLen];
memcpy(mMsg, elem.mMsg, mMsgLen);
@@ -71,31 +64,43 @@
}
LogBufferElement::~LogBufferElement() {
- delete[] mMsg;
+ if (!mDropped) {
+ delete[] mMsg;
+ }
}
uint32_t LogBufferElement::getTag() const {
- return (isBinary() &&
- ((mDropped && mMsg != nullptr) ||
- (!mDropped && mMsgLen >= sizeof(android_event_header_t))))
- ? reinterpret_cast<const android_event_header_t*>(mMsg)->tag
- : 0;
+ // Binary buffers have no tag.
+ if (!isBinary()) {
+ return 0;
+ }
+
+ // Dropped messages store the tag in place of mMsg.
+ if (mDropped) {
+ return mTag;
+ }
+
+ // For non-dropped messages, we get the tag from the message header itself.
+ if (mMsgLen < sizeof(android_event_header_t)) {
+ return 0;
+ }
+
+ return reinterpret_cast<const android_event_header_t*>(mMsg)->tag;
}
uint16_t LogBufferElement::setDropped(uint16_t value) {
- // The tag information is saved in mMsg data, if the tag is non-zero
- // save only the information needed to get the tag.
- if (getTag() != 0) {
- if (mMsgLen > sizeof(android_event_header_t)) {
- char* truncated_msg = new char[sizeof(android_event_header_t)];
- memcpy(truncated_msg, mMsg, sizeof(android_event_header_t));
- delete[] mMsg;
- mMsg = truncated_msg;
- } // mMsgLen == sizeof(android_event_header_t), already at minimum.
- } else {
- delete[] mMsg;
- mMsg = nullptr;
+ if (mDropped) {
+ return mDroppedCount = value;
}
+
+ // The tag information is saved in mMsg data, which is in a union with mTag, used after mDropped
+ // is set to true. Therefore we save the tag value aside, delete mMsg, then set mTag to the tag
+ // value in its place.
+ auto old_tag = getTag();
+ delete[] mMsg;
+ mMsg = nullptr;
+
+ mTag = old_tag;
mDropped = true;
return mDroppedCount = value;
}
diff --git a/logd/LogBufferElement.h b/logd/LogBufferElement.h
index 57b0a95..da4991b 100644
--- a/logd/LogBufferElement.h
+++ b/logd/LogBufferElement.h
@@ -41,7 +41,10 @@
const uint32_t mPid;
const uint32_t mTid;
log_time mRealTime;
- char* mMsg;
+ union {
+ char* mMsg; // mDropped == false
+ int32_t mTag; // mDropped == true
+ };
union {
const uint16_t mMsgLen; // mDropped == false
uint16_t mDroppedCount; // mDropped == true