From 00bc9142c42f3652d1f3d5799abc270f623cc390 Mon Sep 17 00:00:00 2001
From: Takeshi Nakatani <ggtakec@gmail.com>
Date: Sun, 17 Sep 2017 09:16:05 +0000
Subject: [PATCH] Fixed potential atomic violation in S3fsCurl::AddUserAgent -
 #633

---
 src/curl.cpp | 29 +++++++++++++++--------------
 src/curl.h   |  2 ++
 src/s3fs.cpp |  3 +++
 3 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/src/curl.cpp b/src/curl.cpp
index 579af5e..fca5113 100644
--- a/src/curl.cpp
+++ b/src/curl.cpp
@@ -363,6 +363,7 @@ curltime_t       S3fsCurl::curl_times;
 curlprogress_t   S3fsCurl::curl_progress;
 string           S3fsCurl::curl_ca_bundle;
 mimes_t          S3fsCurl::mimeTypes;
+string           S3fsCurl::userAgent;
 int              S3fsCurl::max_parallel_cnt    = 5;              // default
 off_t            S3fsCurl::multipart_size      = MULTIPART_SIZE; // default
 bool             S3fsCurl::is_sigv4            = true;           // default
@@ -614,6 +615,19 @@ bool S3fsCurl::InitMimeType(const char* MimeFile)
   return true;
 }
 
+void S3fsCurl::InitUserAgent(void)
+{
+  if(S3fsCurl::userAgent.empty()){
+    S3fsCurl::userAgent =  "s3fs/";
+    S3fsCurl::userAgent += VERSION;
+    S3fsCurl::userAgent += " (commit hash ";
+    S3fsCurl::userAgent += COMMIT_HASH_VAL;
+    S3fsCurl::userAgent += "; ";
+    S3fsCurl::userAgent += s3fs_crypt_lib_name();
+    S3fsCurl::userAgent += ")";
+  }
+}
+
 //
 // @param s e.g., "index.html"
 // @return e.g., "text/html"
@@ -1480,20 +1494,7 @@ bool S3fsCurl::AddUserAgent(CURL* hCurl)
     return false;
   }
   if(S3fsCurl::IsUserAgentFlag()){
-    static string strua;
-    static bool   init = false;
-
-    if(!init){
-      strua =  "s3fs/";
-      strua += VERSION;
-      strua += " (commit hash ";
-      strua += COMMIT_HASH_VAL;
-      strua += "; ";
-      strua += s3fs_crypt_lib_name();
-      strua += ")";
-      init = true;
-    }
-    curl_easy_setopt(hCurl, CURLOPT_USERAGENT, strua.c_str());
+    curl_easy_setopt(hCurl, CURLOPT_USERAGENT, S3fsCurl::userAgent.c_str());
   }
   return true;
 }
diff --git a/src/curl.h b/src/curl.h
index c75b4dd..be9feb5 100644
--- a/src/curl.h
+++ b/src/curl.h
@@ -236,6 +236,7 @@ class S3fsCurl
     static curlprogress_t   curl_progress;
     static std::string      curl_ca_bundle;
     static mimes_t          mimeTypes;
+    static std::string      userAgent;
     static int              max_parallel_cnt;
     static off_t            multipart_size;
     static bool             is_sigv4;
@@ -377,6 +378,7 @@ class S3fsCurl
     static bool IsSignatureV4(void) { return S3fsCurl::is_sigv4; }
     static bool SetUserAgentFlag(bool isset) { bool bresult = S3fsCurl::is_ua; S3fsCurl::is_ua = isset; return bresult; }
     static bool IsUserAgentFlag(void) { return S3fsCurl::is_ua; }
+    static void InitUserAgent(void);
 
     // methods
     bool CreateCurlHandle(bool force = false);
diff --git a/src/s3fs.cpp b/src/s3fs.cpp
index 8df9aa2..7f159b8 100644
--- a/src/s3fs.cpp
+++ b/src/s3fs.cpp
@@ -4935,6 +4935,9 @@ int main(int argc, char* argv[])
     exit(EXIT_FAILURE);
   }
 
+  // set user agent
+  S3fsCurl::InitUserAgent();
+
   // There's room for more command line error checking
 
   // Check to see if the bucket name contains periods and https (SSL) is