logd: decouple LogTags from LogBuffer

LogBuffer needs a pointer to LogTags, but it should not own the
instance.  It should not provide accessors into LogTags either.

Also, clean up CommandListener a bit.

Test: logging unit tests
Change-Id: Ic0c86a2bac0c4dd80262278588b9fdc2326dbe5b
diff --git a/logd/CommandListener.cpp b/logd/CommandListener.cpp
index 694b5fa..1e7a33a 100644
--- a/logd/CommandListener.cpp
+++ b/logd/CommandListener.cpp
@@ -38,37 +38,20 @@
 #include "LogCommand.h"
 #include "LogUtils.h"
 
-CommandListener::CommandListener(LogBuffer* buf, LogReader* /*reader*/,
-                                 LogListener* /*swl*/)
-    : FrameworkListener(getLogSocket()) {
-    // registerCmd(new ShutdownCmd(buf, writer, swl));
-    registerCmd(new ClearCmd(buf));
-    registerCmd(new GetBufSizeCmd(buf));
-    registerCmd(new SetBufSizeCmd(buf));
-    registerCmd(new GetBufSizeUsedCmd(buf));
-    registerCmd(new GetStatisticsCmd(buf));
-    registerCmd(new SetPruneListCmd(buf));
-    registerCmd(new GetPruneListCmd(buf));
-    registerCmd(new GetEventTagCmd(buf));
-    registerCmd(new ReinitCmd());
+CommandListener::CommandListener(LogBuffer* buf, LogTags* tags)
+    : FrameworkListener(getLogSocket()), buf_(buf), tags_(tags) {
+    registerCmd(new ClearCmd(this));
+    registerCmd(new GetBufSizeCmd(this));
+    registerCmd(new SetBufSizeCmd(this));
+    registerCmd(new GetBufSizeUsedCmd(this));
+    registerCmd(new GetStatisticsCmd(this));
+    registerCmd(new SetPruneListCmd(this));
+    registerCmd(new GetPruneListCmd(this));
+    registerCmd(new GetEventTagCmd(this));
+    registerCmd(new ReinitCmd(this));
     registerCmd(new ExitCmd(this));
 }
 
-CommandListener::ShutdownCmd::ShutdownCmd(LogReader* reader, LogListener* swl)
-    : LogCommand("shutdown"), mReader(*reader), mSwl(*swl) {
-}
-
-int CommandListener::ShutdownCmd::runCommand(SocketClient* /*cli*/,
-                                             int /*argc*/, char** /*argv*/) {
-    mSwl.stopListener();
-    mReader.stopListener();
-    exit(0);
-}
-
-CommandListener::ClearCmd::ClearCmd(LogBuffer* buf)
-    : LogCommand("clear"), mBuf(*buf) {
-}
-
 static void setname() {
     static bool name_set;
     if (!name_set) {
@@ -96,14 +79,10 @@
         return 0;
     }
 
-    cli->sendMsg(mBuf.clear((log_id_t)id, uid) ? "busy" : "success");
+    cli->sendMsg(buf()->clear((log_id_t)id, uid) ? "busy" : "success");
     return 0;
 }
 
-CommandListener::GetBufSizeCmd::GetBufSizeCmd(LogBuffer* buf)
-    : LogCommand("getLogSize"), mBuf(*buf) {
-}
-
 int CommandListener::GetBufSizeCmd::runCommand(SocketClient* cli, int argc,
                                                char** argv) {
     setname();
@@ -118,17 +97,13 @@
         return 0;
     }
 
-    unsigned long size = mBuf.getSize((log_id_t)id);
+    unsigned long size = buf()->getSize((log_id_t)id);
     char buf[512];
     snprintf(buf, sizeof(buf), "%lu", size);
     cli->sendMsg(buf);
     return 0;
 }
 
-CommandListener::SetBufSizeCmd::SetBufSizeCmd(LogBuffer* buf)
-    : LogCommand("setLogSize"), mBuf(*buf) {
-}
-
 int CommandListener::SetBufSizeCmd::runCommand(SocketClient* cli, int argc,
                                                char** argv) {
     setname();
@@ -149,7 +124,7 @@
     }
 
     unsigned long size = atol(argv[2]);
-    if (mBuf.setSize((log_id_t)id, size)) {
+    if (buf()->setSize((log_id_t)id, size)) {
         cli->sendMsg("Range Error");
         return 0;
     }
@@ -158,10 +133,6 @@
     return 0;
 }
 
-CommandListener::GetBufSizeUsedCmd::GetBufSizeUsedCmd(LogBuffer* buf)
-    : LogCommand("getLogSizeUsed"), mBuf(*buf) {
-}
-
 int CommandListener::GetBufSizeUsedCmd::runCommand(SocketClient* cli, int argc,
                                                    char** argv) {
     setname();
@@ -176,17 +147,13 @@
         return 0;
     }
 
-    unsigned long size = mBuf.getSizeUsed((log_id_t)id);
+    unsigned long size = buf()->getSizeUsed((log_id_t)id);
     char buf[512];
     snprintf(buf, sizeof(buf), "%lu", size);
     cli->sendMsg(buf);
     return 0;
 }
 
-CommandListener::GetStatisticsCmd::GetStatisticsCmd(LogBuffer* buf)
-    : LogCommand("getStatistics"), mBuf(*buf) {
-}
-
 // This returns a string with a length prefix with the format <length>\n<data>\n\f.  The length
 // prefix includes the length of the prefix itself.
 static std::string PackageString(const std::string& str) {
@@ -241,25 +208,17 @@
         }
     }
 
-    cli->sendMsg(PackageString(mBuf.formatStatistics(uid, pid, logMask)).c_str());
+    cli->sendMsg(PackageString(buf()->formatStatistics(uid, pid, logMask)).c_str());
     return 0;
 }
 
-CommandListener::GetPruneListCmd::GetPruneListCmd(LogBuffer* buf)
-    : LogCommand("getPruneList"), mBuf(*buf) {
-}
-
 int CommandListener::GetPruneListCmd::runCommand(SocketClient* cli,
                                                  int /*argc*/, char** /*argv*/) {
     setname();
-    cli->sendMsg(PackageString(mBuf.formatPrune()).c_str());
+    cli->sendMsg(PackageString(buf()->formatPrune()).c_str());
     return 0;
 }
 
-CommandListener::SetPruneListCmd::SetPruneListCmd(LogBuffer* buf)
-    : LogCommand("setPruneList"), mBuf(*buf) {
-}
-
 int CommandListener::SetPruneListCmd::runCommand(SocketClient* cli, int argc,
                                                  char** argv) {
     setname();
@@ -276,7 +235,7 @@
         str += argv[i];
     }
 
-    int ret = mBuf.initPrune(str.c_str());
+    int ret = buf()->initPrune(str.c_str());
 
     if (ret) {
         cli->sendMsg("Invalid");
@@ -288,10 +247,6 @@
     return 0;
 }
 
-CommandListener::GetEventTagCmd::GetEventTagCmd(LogBuffer* buf)
-    : LogCommand("getEventTag"), mBuf(*buf) {
-}
-
 int CommandListener::GetEventTagCmd::runCommand(SocketClient* cli, int argc,
                                                 char** argv) {
     setname();
@@ -328,18 +283,15 @@
             cli->sendMsg("can not mix id= with either format= or name=");
             return 0;
         }
-        cli->sendMsg(PackageString(mBuf.formatEntry(atoi(id), uid)).c_str());
+        cli->sendMsg(PackageString(tags()->formatEntry(atoi(id), uid)).c_str());
         return 0;
     }
 
-    cli->sendMsg(PackageString(mBuf.formatGetEventTag(uid, name, format)).c_str());
+    cli->sendMsg(PackageString(tags()->formatGetEventTag(uid, name, format)).c_str());
 
     return 0;
 }
 
-CommandListener::ReinitCmd::ReinitCmd() : LogCommand("reinit") {
-}
-
 int CommandListener::ReinitCmd::runCommand(SocketClient* cli, int /*argc*/,
                                            char** /*argv*/) {
     setname();
@@ -351,16 +303,12 @@
     return 0;
 }
 
-CommandListener::ExitCmd::ExitCmd(CommandListener* parent)
-    : LogCommand("EXIT"), mParent(*parent) {
-}
-
 int CommandListener::ExitCmd::runCommand(SocketClient* cli, int /*argc*/,
                                          char** /*argv*/) {
     setname();
 
     cli->sendMsg("success");
-    release(cli);
+    parent_->release(cli);
 
     return 0;
 }
diff --git a/logd/CommandListener.h b/logd/CommandListener.h
index ed99419..80597b2 100644
--- a/logd/CommandListener.h
+++ b/logd/CommandListener.h
@@ -14,85 +14,53 @@
  * limitations under the License.
  */
 
-#ifndef _COMMANDLISTENER_H__
-#define _COMMANDLISTENER_H__
+#pragma once
 
 #include <sysutils/FrameworkListener.h>
+
 #include "LogBuffer.h"
 #include "LogCommand.h"
 #include "LogListener.h"
 #include "LogReader.h"
+#include "LogTags.h"
 
 // See main.cpp for implementation
 void reinit_signal_handler(int /*signal*/);
 
 class CommandListener : public FrameworkListener {
-   public:
-    CommandListener(LogBuffer* buf, LogReader* reader, LogListener* swl);
-    virtual ~CommandListener() {
-    }
+  public:
+    CommandListener(LogBuffer* buf, LogTags* tags);
+    virtual ~CommandListener() {}
 
-   private:
+  private:
     static int getLogSocket();
 
-    class ShutdownCmd : public LogCommand {
-        LogReader& mReader;
-        LogListener& mSwl;
+    LogBuffer* buf_;
+    LogTags* tags_;
 
-       public:
-        ShutdownCmd(LogReader* reader, LogListener* swl);
-        virtual ~ShutdownCmd() {
-        }
-        int runCommand(SocketClient* c, int argc, char** argv);
-    };
-
-#define LogBufferCmd(name)                                      \
+#define LogCmd(name, command_string)                            \
     class name##Cmd : public LogCommand {                       \
-        LogBuffer& mBuf;                                        \
+      public:                                                   \
+        explicit name##Cmd(CommandListener* parent)             \
+            : LogCommand(#command_string), parent_(parent) {}   \
+        virtual ~name##Cmd() {}                                 \
+        int runCommand(SocketClient* c, int argc, char** argv); \
                                                                 \
-       public:                                                  \
-        explicit name##Cmd(LogBuffer* buf);                     \
-        virtual ~name##Cmd() {                                  \
-        }                                                       \
-        int runCommand(SocketClient* c, int argc, char** argv); \
+      private:                                                  \
+        LogBuffer* buf() const { return parent_->buf_; }        \
+        LogTags* tags() const { return parent_->tags_; }        \
+        CommandListener* parent_;                               \
     }
 
-    LogBufferCmd(Clear);
-    LogBufferCmd(GetBufSize);
-    LogBufferCmd(SetBufSize);
-    LogBufferCmd(GetBufSizeUsed);
-    LogBufferCmd(GetStatistics);
-    LogBufferCmd(GetPruneList);
-    LogBufferCmd(SetPruneList);
-    LogBufferCmd(GetEventTag);
-
-#define LogCmd(name)                                            \
-    class name##Cmd : public LogCommand {                       \
-       public:                                                  \
-        name##Cmd();                                            \
-        virtual ~name##Cmd() {                                  \
-        }                                                       \
-        int runCommand(SocketClient* c, int argc, char** argv); \
-    }
-
-    LogCmd(Reinit);
-
-#define LogParentCmd(name)                                      \
-    class name##Cmd : public LogCommand {                       \
-        CommandListener& mParent;                               \
-                                                                \
-       public:                                                  \
-        name##Cmd();                                            \
-        explicit name##Cmd(CommandListener* parent);            \
-        virtual ~name##Cmd() {                                  \
-        }                                                       \
-        int runCommand(SocketClient* c, int argc, char** argv); \
-        void release(SocketClient* c) {                         \
-            mParent.release(c);                                 \
-        }                                                       \
-    }
-
-    LogParentCmd(Exit);
+    LogCmd(Clear, clear);
+    LogCmd(GetBufSize, getLogSize);
+    LogCmd(SetBufSize, setLogSize);
+    LogCmd(GetBufSizeUsed, getLogSizeUsed);
+    LogCmd(GetStatistics, getStatistics);
+    LogCmd(GetPruneList, getPruneList);
+    LogCmd(SetPruneList, setPruneList);
+    LogCmd(GetEventTag, getEventTag);
+    LogCmd(Reinit, reinit);
+    LogCmd(Exit, EXIT);
+#undef LogCmd
 };
-
-#endif
diff --git a/logd/LogBuffer.cpp b/logd/LogBuffer.cpp
index 36273de..443fd98 100644
--- a/logd/LogBuffer.cpp
+++ b/logd/LogBuffer.cpp
@@ -109,8 +109,8 @@
     LogTimeEntry::unlock();
 }
 
-LogBuffer::LogBuffer(LastLogTimes* times)
-    : monotonic(android_log_clockid() == CLOCK_MONOTONIC), mTimes(*times) {
+LogBuffer::LogBuffer(LastLogTimes* times, LogTags* tags)
+    : monotonic(android_log_clockid() == CLOCK_MONOTONIC), mTimes(*times), tags_(tags) {
     pthread_rwlock_init(&mLogElementsLock, nullptr);
 
     log_id_for_each(i) {
@@ -232,7 +232,7 @@
     const char* tag = nullptr;
     size_t tag_len = 0;
     if (log_id == LOG_ID_EVENTS || log_id == LOG_ID_STATS) {
-        tag = tagToName(elem->getTag());
+        tag = tags_->tagToName(elem->getTag());
         if (tag) {
             tag_len = strlen(tag);
         }
diff --git a/logd/LogBuffer.h b/logd/LogBuffer.h
index 458fbbb..b8e64d0 100644
--- a/logd/LogBuffer.h
+++ b/logd/LogBuffer.h
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef _LOGD_LOG_BUFFER_H__
-#define _LOGD_LOG_BUFFER_H__
+#pragma once
 
 #include <sys/types.h>
 
@@ -98,8 +97,6 @@
 
     bool monotonic;
 
-    LogTags tags;
-
     LogBufferElement* lastLoggedElements[LOG_ID_MAX];
     LogBufferElement* droppedElements[LOG_ID_MAX];
     void log(LogBufferElement* elem);
@@ -107,7 +104,7 @@
    public:
     LastLogTimes& mTimes;
 
-    explicit LogBuffer(LastLogTimes* times);
+    LogBuffer(LastLogTimes* times, LogTags* tags);
     ~LogBuffer();
     void init();
     bool isMonotonic() {
@@ -143,17 +140,6 @@
         return mPrune.format();
     }
 
-    std::string formatGetEventTag(uid_t uid, const char* name,
-                                  const char* format) {
-        return tags.formatGetEventTag(uid, name, format);
-    }
-    std::string formatEntry(uint32_t tag, uid_t uid) {
-        return tags.formatEntry(tag, uid);
-    }
-    const char* tagToName(uint32_t tag) {
-        return tags.tagToName(tag);
-    }
-
     // helper must be protected directly or implicitly by wrlock()/unlock()
     const char* pidToName(pid_t pid) {
         return stats.pidToName(pid);
@@ -186,6 +172,6 @@
     // Returns an iterator to the oldest element for a given log type, or mLogElements.end() if
     // there are no logs for the given log type. Requires mLogElementsLock to be held.
     LogBufferElementCollection::iterator GetOldest(log_id_t log_id);
-};
 
-#endif  // _LOGD_LOG_BUFFER_H__
+    LogTags* tags_;
+};
diff --git a/logd/fuzz/log_buffer_log_fuzzer.cpp b/logd/fuzz/log_buffer_log_fuzzer.cpp
index 4d1589b..fa23dcc 100644
--- a/logd/fuzz/log_buffer_log_fuzzer.cpp
+++ b/logd/fuzz/log_buffer_log_fuzzer.cpp
@@ -94,7 +94,8 @@
     }
 
     LastLogTimes times;
-    LogBuffer log_buffer(&times);
+    LogTags tags;
+    LogBuffer log_buffer(&times, &tags);
     size_t data_left = size;
     const uint8_t** pdata = &data;
 
diff --git a/logd/main.cpp b/logd/main.cpp
index 23bbf86..8713147 100644
--- a/logd/main.cpp
+++ b/logd/main.cpp
@@ -52,6 +52,7 @@
 #include "LogBuffer.h"
 #include "LogKlog.h"
 #include "LogListener.h"
+#include "LogTags.h"
 #include "LogUtils.h"
 
 #define KMSG_PRIORITY(PRI)                                 \
@@ -355,6 +356,9 @@
         pthread_attr_destroy(&attr);
     }
 
+    // A cache of event log tags
+    LogTags log_tags;
+
     // Serves the purpose of managing the last logs times read on a
     // socket connection, and as a reader lock on a range of log
     // entries.
@@ -364,7 +368,7 @@
     // LogBuffer is the object which is responsible for holding all
     // log entries.
 
-    logBuf = new LogBuffer(times);
+    logBuf = new LogBuffer(times, &log_tags);
 
     signal(SIGHUP, reinit_signal_handler);
 
@@ -396,7 +400,7 @@
     // Command listener listens on /dev/socket/logd for incoming logd
     // administrative commands.
 
-    CommandListener* cl = new CommandListener(logBuf, reader, swl);
+    CommandListener* cl = new CommandListener(logBuf, &log_tags);
     if (cl->startListener()) {
         return EXIT_FAILURE;
     }