From 9421b0c0600030f84c81b05e708e2d7b1a3f9b1c Mon Sep 17 00:00:00 2001
From: Mark Salyzyn <salyzyn@google.com>
Date: Thu, 26 Feb 2015 14:33:35 -0800
Subject: [PATCH] logcat: do not stop on unexpected log ID

We are changing the log read API to allow event notification
regarding logging system data loss. We would like these out
of band events to be reported.

Change-Id: I9e802113604d8cc0fc9adff0d1e014bbc40914fe
---
 logcat/logcat.cpp | 34 +++++++++++++++-------------------
 1 file changed, 15 insertions(+), 19 deletions(-)

diff --git a/logcat/logcat.cpp b/logcat/logcat.cpp
index cd5003edc..ea1091500 100644
--- a/logcat/logcat.cpp
+++ b/logcat/logcat.cpp
@@ -61,9 +61,7 @@ static int g_maxRotatedLogs = DEFAULT_MAX_ROTATED_LOGS; // 0 means "unbounded"
 static int g_outFD = -1;
 static off_t g_outByteCount = 0;
 static int g_printBinary = 0;
-static int g_devCount = 0;
-
-static EventTagMap* g_eventTagMap = NULL;
+static int g_devCount = 0;                              // >1 means multiple
 
 static int openLogFile (const char *pathname)
 {
@@ -133,8 +131,15 @@ static void processBuffer(log_device_t* dev, struct log_msg *buf)
     char binaryMsgBuf[1024];
 
     if (dev->binary) {
+        static bool hasOpenedEventTagMap = false;
+        static EventTagMap *eventTagMap = NULL;
+
+        if (!eventTagMap && !hasOpenedEventTagMap) {
+            eventTagMap = android_openEventTagMap(EVENT_TAG_MAP_FILE);
+            hasOpenedEventTagMap = true;
+        }
         err = android_log_processBinaryLogBuffer(&buf->entry_v1, &entry,
-                                                 g_eventTagMap,
+                                                 eventTagMap,
                                                  binaryMsgBuf,
                                                  sizeof(binaryMsgBuf));
         //printf(">>> pri=%d len=%d msg='%s'\n",
@@ -331,7 +336,6 @@ int main(int argc, char **argv)
     const char *forceFilters = NULL;
     log_device_t* devices = NULL;
     log_device_t* dev;
-    bool needBinary = false;
     bool printDividers = false;
     struct logger_list *logger_list;
     unsigned int tail_lines = 0;
@@ -469,7 +473,6 @@ int main(int argc, char **argv)
 
                     devices = dev = NULL;
                     android::g_devCount = 0;
-                    needBinary = false;
                     for(int i = LOG_ID_MIN; i < LOG_ID_MAX; ++i) {
                         const char *name = android_log_id_to_name((log_id_t)i);
                         log_id_t log_id = android_name_to_log_id(name);
@@ -488,17 +491,11 @@ int main(int argc, char **argv)
                             devices = dev = d;
                         }
                         android::g_devCount++;
-                        if (binary) {
-                            needBinary = true;
-                        }
                     }
                     break;
                 }
 
                 bool binary = strcmp(optarg, "events") == 0;
-                if (binary) {
-                    needBinary = true;
-                }
 
                 if (devices) {
                     dev = devices;
@@ -848,17 +845,15 @@ int main(int argc, char **argv)
     //LOG_EVENT_LONG(11, 0x1122334455667788LL);
     //LOG_EVENT_STRING(0, "whassup, doc?");
 
-    if (needBinary)
-        android::g_eventTagMap = android_openEventTagMap(EVENT_TAG_MAP_FILE);
-
     dev = NULL;
+    log_device_t unexpected("unexpected", false, '?');
     while (1) {
         struct log_msg log_msg;
         log_device_t* d;
         int ret = android_logger_list_read(logger_list, &log_msg);
 
         if (ret == 0) {
-            fprintf(stderr, "read: Unexpected EOF!\n");
+            fprintf(stderr, "read: unexpected EOF!\n");
             exit(EXIT_FAILURE);
         }
 
@@ -868,7 +863,7 @@ int main(int argc, char **argv)
             }
 
             if (ret == -EIO) {
-                fprintf(stderr, "read: Unexpected EOF!\n");
+                fprintf(stderr, "read: unexpected EOF!\n");
                 exit(EXIT_FAILURE);
             }
             if (ret == -EINVAL) {
@@ -885,8 +880,9 @@ int main(int argc, char **argv)
             }
         }
         if (!d) {
-            fprintf(stderr, "read: Unexpected log ID!\n");
-            exit(EXIT_FAILURE);
+            android::g_devCount = 2; // set to Multiple
+            d = &unexpected;
+            d->binary = log_msg.id() == LOG_ID_EVENTS;
         }
 
         if (dev != d) {