From 6bd71aef37dc037ca82d036507408d03226ec57f Mon Sep 17 00:00:00 2001
From: Yao Chen <yaochen@google.com>
Date: Thu, 6 Dec 2018 13:03:12 -0800
Subject: [PATCH] Add a function to pass byte array to the log context.

The existing APIs will truncate the byte array in case of '\0' in between.

Test: test_drive with atom 103
Change-Id: I104d35b330c6b52e2fdce1f5d4305dca08228f1b
---
 libstats/include/stats_event_list.h | 10 ++++++-
 libstats/stats_event_list.c         | 44 +++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/libstats/include/stats_event_list.h b/libstats/include/stats_event_list.h
index a9832db29..41ca79bcd 100644
--- a/libstats/include/stats_event_list.h
+++ b/libstats/include/stats_event_list.h
@@ -26,7 +26,7 @@ void reset_log_context(android_log_context ctx);
 int write_to_logger(android_log_context context, log_id_t id);
 void note_log_drop();
 void stats_log_close();
-
+int android_log_write_char_array(android_log_context ctx, const char* value, size_t len);
 #ifdef __cplusplus
 }
 #endif
@@ -244,6 +244,14 @@ class stats_event_list {
         return ret >= 0;
     }
 
+    bool AppendCharArray(const char* value, size_t len) {
+        int retval = android_log_write_char_array(ctx, value, len);
+        if (retval < 0) {
+            ret = retval;
+        }
+        return ret >= 0;
+    }
+
     android_log_list_element read() { return android_log_read_next(ctx); }
     android_log_list_element peek() { return android_log_peek_next(ctx); }
 };
diff --git a/libstats/stats_event_list.c b/libstats/stats_event_list.c
index 72770d48a..f4a7e9405 100644
--- a/libstats/stats_event_list.c
+++ b/libstats/stats_event_list.c
@@ -193,3 +193,47 @@ static int __write_to_statsd_init(struct iovec* vec, size_t nr) {
     errno = save_errno;
     return ret;
 }
+
+static inline void copy4LE(uint8_t* buf, uint32_t val) {
+    buf[0] = val & 0xFF;
+    buf[1] = (val >> 8) & 0xFF;
+    buf[2] = (val >> 16) & 0xFF;
+    buf[3] = (val >> 24) & 0xFF;
+}
+
+// Note: this function differs from android_log_write_string8_len in that the length passed in
+// should be treated as actual length and not max length.
+int android_log_write_char_array(android_log_context ctx, const char* value, size_t actual_len) {
+    size_t needed;
+    ssize_t len = actual_len;
+    android_log_context_internal* context;
+
+    context = (android_log_context_internal*)ctx;
+    if (!context || (kAndroidLoggerWrite != context->read_write_flag)) {
+        return -EBADF;
+    }
+    if (context->overflow) {
+        return -EIO;
+    }
+    if (!value) {
+        value = "";
+        len = 0;
+    }
+    needed = sizeof(uint8_t) + sizeof(int32_t) + len;
+    if ((context->pos + needed) > MAX_EVENT_PAYLOAD) {
+        /* Truncate string for delivery */
+        len = MAX_EVENT_PAYLOAD - context->pos - 1 - sizeof(int32_t);
+        if (len <= 0) {
+            context->overflow = true;
+            return -EIO;
+        }
+    }
+    context->count[context->list_nest_depth]++;
+    context->storage[context->pos + 0] = EVENT_TYPE_STRING;
+    copy4LE(&context->storage[context->pos + 1], len);
+    if (len) {
+        memcpy(&context->storage[context->pos + 5], value, len);
+    }
+    context->pos += needed;
+    return len;
+}