[BUILD] Fixes compiling problems in NDK r27 (open-telemetry#3517)

* Fixes compiling problems in NDK r27

* All APIs of C style file should use `std::` version.

Author: owent

exporters/otlp/src/otlp_file_client.cc

@@ -1,6 +1,8 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
+#include <nlohmann/json.hpp>
+
 #include <limits.h>
 #include <atomic>
 #include <chrono>
@@ -12,7 +14,6 @@
 #include <fstream>
 #include <functional>
 #include <mutex>
-#include <nlohmann/json.hpp>
 #include <ratio>
 #include <string>
 #include <thread>
@@ -1028,21 +1029,21 @@ class OPENTELEMETRY_LOCAL_SYMBOL OtlpFileSystemBackend : public OtlpFileAppender
 
     MaybeRotateLog(data.size());
 
-    std::shared_ptr<FILE> out = OpenLogFile(true);
+    std::shared_ptr<std::FILE> out = OpenLogFile(true);
     if (!out)
     {
       return;
     }
 
-    fwrite(data.data(), 1, data.size(), out.get());
+    std::fwrite(data.data(), 1, data.size(), out.get());
 
     {
       std::lock_guard<std::mutex> lock_guard{file_->file_lock};
 
       file_->record_count += record_count;
 
       // Pipe file size always returns 0, we ignore the size limit of it.
-      auto written_size = ftell(out.get());
+      auto written_size = std::ftell(out.get());
       if (written_size >= 0)
       {
         file_->written_size = static_cast<std::size_t>(written_size);
@@ -1054,7 +1055,7 @@ class OPENTELEMETRY_LOCAL_SYMBOL OtlpFileSystemBackend : public OtlpFileAppender
         {
           file_->left_flush_record_count = options_.flush_count;
 
-          fflush(out.get());
+          std::fflush(out.get());
 
           file_->flushed_record_count.store(file_->record_count.load(std::memory_order_acquire),
                                             std::memory_order_release);
@@ -1216,7 +1217,7 @@ class OPENTELEMETRY_LOCAL_SYMBOL OtlpFileSystemBackend : public OtlpFileAppender
     OpenLogFile(false);
   }
 
-  std::shared_ptr<FILE> OpenLogFile(bool destroy_content)
+  std::shared_ptr<std::FILE> OpenLogFile(bool destroy_content)
   {
     std::lock_guard<std::mutex> lock_guard{file_->file_lock};
 
@@ -1238,8 +1239,6 @@ class OPENTELEMETRY_LOCAL_SYMBOL OtlpFileSystemBackend : public OtlpFileAppender
     }
     file_path[file_path_size] = 0;
 
-    std::shared_ptr<FILE> of = std::make_shared<FILE>();
-
     std::string directory_name = FileSystemUtil::DirName(file_path);
     if (!directory_name.empty())
     {
@@ -1294,10 +1293,10 @@ class OPENTELEMETRY_LOCAL_SYMBOL OtlpFileSystemBackend : public OtlpFileAppender
                               << " failed with pattern: " << options_.file_pattern << hint);
       return nullptr;
     }
-    of = std::shared_ptr<std::FILE>(new_file, fclose);
+    std::shared_ptr<std::FILE> of = std::shared_ptr<std::FILE>(new_file, fclose);
 
-    fseek(of.get(), 0, SEEK_END);
-    file_->written_size = static_cast<size_t>(ftell(of.get()));
+    std::fseek(of.get(), 0, SEEK_END);
+    file_->written_size = static_cast<size_t>(std::ftell(of.get()));
 
     file_->current_file    = of;
     file_->last_checkpoint = std::chrono::system_clock::to_time_t(std::chrono::system_clock::now());
@@ -1513,7 +1512,7 @@ class OPENTELEMETRY_LOCAL_SYMBOL OtlpFileSystemBackend : public OtlpFileAppender
 
             if (concurrency_file->current_file)
             {
-              fflush(concurrency_file->current_file.get());
+              std::fflush(concurrency_file->current_file.get());
             }
 
             concurrency_file->flushed_record_count.store(current_record_count,
@@ -1568,7 +1567,7 @@ class OPENTELEMETRY_LOCAL_SYMBOL OtlpFileSystemBackend : public OtlpFileAppender
     std::size_t rotate_index;
     std::size_t written_size;
     std::size_t left_flush_record_count;
-    std::shared_ptr<FILE> current_file;
+    std::shared_ptr<std::FILE> current_file;
     std::mutex file_lock;
     std::time_t last_checkpoint;
     std::string file_path;