| /* |
| * Copyright (C) 2012-2014 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "LogBufferElement.h" |
| |
| #include <ctype.h> |
| #include <endian.h> |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <time.h> |
| #include <unistd.h> |
| |
| #include <log/log_read.h> |
| #include <private/android_logger.h> |
| |
| #include "LogStatistics.h" |
| #include "LogUtils.h" |
| |
| LogBufferElement::LogBufferElement(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, |
| pid_t tid, uint64_t sequence, const char* msg, uint16_t len) |
| : mUid(uid), |
| mPid(pid), |
| mTid(tid), |
| mSequence(sequence), |
| mRealTime(realtime), |
| mMsgLen(len), |
| mLogId(log_id), |
| mDropped(false) { |
| mMsg = new char[len]; |
| memcpy(mMsg, msg, len); |
| } |
| |
| LogBufferElement::LogBufferElement(const LogBufferElement& elem) |
| : mUid(elem.mUid), |
| mPid(elem.mPid), |
| mTid(elem.mTid), |
| mSequence(elem.mSequence), |
| mRealTime(elem.mRealTime), |
| mMsgLen(elem.mMsgLen), |
| mLogId(elem.mLogId), |
| mDropped(elem.mDropped) { |
| if (mDropped) { |
| mTag = elem.getTag(); |
| } else { |
| mMsg = new char[mMsgLen]; |
| memcpy(mMsg, elem.mMsg, mMsgLen); |
| } |
| } |
| |
| LogBufferElement::LogBufferElement(LogBufferElement&& elem) |
| : mUid(elem.mUid), |
| mPid(elem.mPid), |
| mTid(elem.mTid), |
| mSequence(elem.mSequence), |
| mRealTime(elem.mRealTime), |
| mMsgLen(elem.mMsgLen), |
| mLogId(elem.mLogId), |
| mDropped(elem.mDropped) { |
| if (mDropped) { |
| mTag = elem.getTag(); |
| } else { |
| mMsg = elem.mMsg; |
| elem.mMsg = nullptr; |
| } |
| } |
| |
| LogBufferElement::~LogBufferElement() { |
| if (!mDropped) { |
| delete[] mMsg; |
| } |
| } |
| |
| uint32_t LogBufferElement::getTag() const { |
| // 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) { |
| 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; |
| } |
| |
| // caller must own and free character string |
| char* android::tidToName(pid_t tid) { |
| char* retval = nullptr; |
| char buffer[256]; |
| snprintf(buffer, sizeof(buffer), "/proc/%u/comm", tid); |
| int fd = open(buffer, O_RDONLY); |
| if (fd >= 0) { |
| ssize_t ret = read(fd, buffer, sizeof(buffer)); |
| if (ret >= (ssize_t)sizeof(buffer)) { |
| ret = sizeof(buffer) - 1; |
| } |
| while ((ret > 0) && isspace(buffer[ret - 1])) { |
| --ret; |
| } |
| if (ret > 0) { |
| buffer[ret] = '\0'; |
| retval = strdup(buffer); |
| } |
| close(fd); |
| } |
| |
| // if nothing for comm, check out cmdline |
| char* name = android::pidToName(tid); |
| if (!retval) { |
| retval = name; |
| name = nullptr; |
| } |
| |
| // check if comm is truncated, see if cmdline has full representation |
| if (name) { |
| // impossible for retval to be NULL if name not NULL |
| size_t retval_len = strlen(retval); |
| size_t name_len = strlen(name); |
| // KISS: ToDo: Only checks prefix truncated, not suffix, or both |
| if ((retval_len < name_len) && |
| !fastcmp<strcmp>(retval, name + name_len - retval_len)) { |
| free(retval); |
| retval = name; |
| } else { |
| free(name); |
| } |
| } |
| return retval; |
| } |
| |
| // assumption: mMsg == NULL |
| size_t LogBufferElement::populateDroppedMessage(char*& buffer, LogStatistics* stats, |
| bool lastSame) { |
| static const char tag[] = "chatty"; |
| |
| if (!__android_log_is_loggable_len(ANDROID_LOG_INFO, tag, strlen(tag), |
| ANDROID_LOG_VERBOSE)) { |
| return 0; |
| } |
| |
| static const char format_uid[] = "uid=%u%s%s %s %u line%s"; |
| const char* name = stats->UidToName(mUid); |
| const char* commName = android::tidToName(mTid); |
| if (!commName && (mTid != mPid)) { |
| commName = android::tidToName(mPid); |
| } |
| if (!commName) { |
| commName = stats->PidToName(mPid); |
| } |
| if (name && name[0] && commName && (name[0] == commName[0])) { |
| size_t len = strlen(name + 1); |
| if (!strncmp(name + 1, commName + 1, len)) { |
| if (commName[len + 1] == '\0') { |
| free(const_cast<char*>(commName)); |
| commName = nullptr; |
| } else { |
| free(const_cast<char*>(name)); |
| name = nullptr; |
| } |
| } |
| } |
| if (name) { |
| char* buf = nullptr; |
| int result = asprintf(&buf, "(%s)", name); |
| if (result != -1) { |
| free(const_cast<char*>(name)); |
| name = buf; |
| } |
| } |
| if (commName) { |
| char* buf = nullptr; |
| int result = asprintf(&buf, " %s", commName); |
| if (result != -1) { |
| free(const_cast<char*>(commName)); |
| commName = buf; |
| } |
| } |
| // identical to below to calculate the buffer size required |
| const char* type = lastSame ? "identical" : "expire"; |
| size_t len = snprintf(nullptr, 0, format_uid, mUid, name ? name : "", |
| commName ? commName : "", type, getDropped(), |
| (getDropped() > 1) ? "s" : ""); |
| |
| size_t hdrLen; |
| if (isBinary()) { |
| hdrLen = sizeof(android_log_event_string_t); |
| } else { |
| hdrLen = 1 + sizeof(tag); |
| } |
| |
| buffer = static_cast<char*>(calloc(1, hdrLen + len + 1)); |
| if (!buffer) { |
| free(const_cast<char*>(name)); |
| free(const_cast<char*>(commName)); |
| return 0; |
| } |
| |
| size_t retval = hdrLen + len; |
| if (isBinary()) { |
| android_log_event_string_t* event = |
| reinterpret_cast<android_log_event_string_t*>(buffer); |
| |
| event->header.tag = htole32(CHATTY_LOG_TAG); |
| event->type = EVENT_TYPE_STRING; |
| event->length = htole32(len); |
| } else { |
| ++retval; |
| buffer[0] = ANDROID_LOG_INFO; |
| strcpy(buffer + 1, tag); |
| } |
| |
| snprintf(buffer + hdrLen, len + 1, format_uid, mUid, name ? name : "", |
| commName ? commName : "", type, getDropped(), |
| (getDropped() > 1) ? "s" : ""); |
| free(const_cast<char*>(name)); |
| free(const_cast<char*>(commName)); |
| |
| return retval; |
| } |
| |
| bool LogBufferElement::FlushTo(LogWriter* writer, LogStatistics* stats, bool lastSame) { |
| struct logger_entry entry = {}; |
| |
| entry.hdr_size = sizeof(struct logger_entry); |
| entry.lid = mLogId; |
| entry.pid = mPid; |
| entry.tid = mTid; |
| entry.uid = mUid; |
| entry.sec = mRealTime.tv_sec; |
| entry.nsec = mRealTime.tv_nsec; |
| |
| char* buffer = nullptr; |
| const char* msg; |
| if (mDropped) { |
| entry.len = populateDroppedMessage(buffer, stats, lastSame); |
| if (!entry.len) return true; |
| msg = buffer; |
| } else { |
| msg = mMsg; |
| entry.len = mMsgLen; |
| } |
| |
| bool retval = writer->Write(entry, msg); |
| |
| if (buffer) free(buffer); |
| |
| return retval; |
| } |