diff --git a/wpiutil/src/main/native/cpp/FileLogger.cpp b/wpiutil/src/main/native/cpp/FileLogger.cpp
index 742d57e9281..6964e706b42 100644
--- a/wpiutil/src/main/native/cpp/FileLogger.cpp
+++ b/wpiutil/src/main/native/cpp/FileLogger.cpp
@@ -4,6 +4,21 @@
 
 #include "wpi/FileLogger.h"
 
+#ifdef __linux__
+#include <fcntl.h>
+#include <sys/inotify.h>
+#include <unistd.h>
+#endif
+
+#include <string>
+#include <string_view>
+#include <tuple>
+#include <utility>
+
+#include <fmt/format.h>
+
+#include "wpi/StringExtras.h"
+
 namespace wpi {
 FileLogger::FileLogger(std::string_view file,
                        std::function<void(std::string_view)> callback)
@@ -26,6 +41,25 @@ FileLogger::FileLogger(std::string_view file,
 #endif
 {
 }
+FileLogger::FileLogger(std::string_view file, log::DataLog& log,
+                       std::string_view key)
+    : FileLogger(file, [entry = log.Start(key, "string"),
+                        buf = wpi::SmallVector<char, 16>{},
+                        &log](std::string_view data) mutable {
+        if (!wpi::contains(data, "\n")) {
+          buf.append(data.begin(), data.end());
+          return;
+        }
+        std::string_view left;
+        std::string_view right;
+        std::string combinedData = fmt::format("{}{}", buf.data(), data);
+        buf.clear();
+        do {
+          std::tie(left, right) = wpi::rsplit(data, "\n");
+          log.AppendString(entry, left, 0);
+        } while (wpi::contains(right, "\n"));
+        buf.append(right.begin(), right.end());
+      }) {}
 FileLogger::FileLogger(FileLogger&& other)
 #ifdef __linux__
     : m_fileHandle{std::exchange(other.m_fileHandle, -1)},
diff --git a/wpiutil/src/main/native/include/wpi/FileLogger.h b/wpiutil/src/main/native/include/wpi/FileLogger.h
index 49e7163f9b2..55d1f804e0c 100644
--- a/wpiutil/src/main/native/include/wpi/FileLogger.h
+++ b/wpiutil/src/main/native/include/wpi/FileLogger.h
@@ -4,20 +4,11 @@
 
 #pragma once
 
-#ifdef __linux__
-#include <fcntl.h>
-#include <sys/inotify.h>
-#include <unistd.h>
-#endif
-
 #include <functional>
 #include <string_view>
 #include <thread>
-#include <utility>
 
 #include "wpi/DataLog.h"
-#include "wpi/SmallVector.h"
-#include "wpi/StringExtras.h"
 
 namespace wpi {
 /**
@@ -45,15 +36,7 @@ class FileLogger {
    * @param log A data log.
    * @param key The log key to append data to.
    */
-  FileLogger(std::string_view file, log::DataLog& log, std::string_view key)
-      : FileLogger(file, [entry = log.Start(key, "string"),
-                          &log](std::string_view data) {
-          wpi::SmallVector<std::string_view, 16> parts;
-          wpi::split(data, parts, "\n");
-          for (auto line : parts) {
-            log.AppendString(entry, line, 0);
-          }
-        }) {}
+  FileLogger(std::string_view file, log::DataLog& log, std::string_view key);
   FileLogger(FileLogger&& other);
   FileLogger& operator=(FileLogger&& rhs);
   ~FileLogger();