1 files changed, 17 insertions, 15 deletions
diff --git a/tensorflow/core/lib/io/inputbuffer.cc b/tensorflow/core/lib/io/inputbuffer.cc
index 9cff1d349e..7efe2dc543 100644
--- a/tensorflow/core/lib/io/inputbuffer.cc
+++ b/tensorflow/core/lib/io/inputbuffer.cc
@@ -15,6 +15,7 @@ limitations under the License.
 
 #include "tensorflow/core/lib/io/inputbuffer.h"
 #include "tensorflow/core/lib/core/errors.h"
+#include "tensorflow/core/platform/logging.h"
 
 namespace tensorflow {
 namespace io {
@@ -43,25 +44,26 @@ Status InputBuffer::FillBuffer() {
 
 Status InputBuffer::ReadLine(string* result) {
   result->clear();
-  int i;
   Status s;
-  for (i = 0;; i++) {
-    if (pos_ == limit_) {
-      // Get more data into buffer
-      s = FillBuffer();
-      if (limit_ == buf_) {
-        break;
+  do {
+    size_t buf_remain = limit_ - pos_;
+    char* newline = static_cast<char*>(memchr(pos_, '\n', buf_remain));
+    if (newline != nullptr) {
+      size_t result_len = newline - pos_;
+      result->append(pos_, result_len);
+      pos_ = newline + 1;
+      if (!result->empty() && result->back() == '\r') {
+        result->resize(result->size() - 1);
       }
-    }
-    char c = *pos_++;
-    if (c == '\n') {
-      // We don't append the '\n' to *result
       return Status::OK();
     }
-    // We don't append '\r' to *result
-    if (c != '\r') {
-      *result += c;
-    }
+    if (buf_remain > 0) result->append(pos_, buf_remain);
+    // Get more data into buffer
+    s = FillBuffer();
+    DCHECK_EQ(pos_, buf_);
+  } while (limit_ != buf_);
+  if (!result->empty() && result->back() == '\r') {
+    result->resize(result->size() - 1);
   }
   if (errors::IsOutOfRange(s) && !result->empty()) {
     return Status::OK();