Merge pull request #579 from ggtakec/master

Added notsup_compat_dir option

doc/man/s3fs.1

@@ -252,6 +252,17 @@ https://curl.haxx.se/docs/ssl-ciphers.html
 s3fs complements lack of information about file/directory mode if a file or a directory object does not have x-amz-meta-mode header.
 As default, s3fs does not complements stat information for a object, then the object will not be able to be allowed to list/modify.
 .TP
+\fB\-o\fR notsup_compat_dir (not support compatibility directory types)
+As a default, s3fs supports objects of the directory type as much as possible and recognizes them as directories.
+Objects that can be recognized as directory objects are "dir/", "dir", "dir_$folder$", and there is a file object that does not have a directory object but contains that directory path.
+s3fs needs redundant communication to support all these directory types.
+The object as the directory created by s3fs is "dir/".
+By restricting s3fs to recognize only "dir/" as a directory, communication traffic can be reduced.
+This option is used to give this restriction to s3fs.
+However, if there is a directory object other than "dir/" in the bucket, specifying this option is not recommended.
+s3fs may not be able to recognize the object correctly if an object created by s3fs exists in the bucket.
+Please use this option when the directory in the bucket is only "dir/" object.
+.TP
 \fB\-o\fR dbglevel (default="crit")
 Set the debug message level. set value as crit(critical), err(error), warn(warning), info(information) to debug level. default debug level is critical.
 If s3fs run with "-d" option, the debug level is set information.

src/s3fs.cpp

@@ -127,6 +127,7 @@ static bool create_bucket         = false;
 static int64_t singlepart_copy_limit = FIVE_GB;
 static bool is_specified_endpoint = false;
 static int s3fs_init_deferred_exit_status = 0;
+static bool support_compat_dir    = true;// default supports compatibility directory type
 
 //-------------------------------------------------------------------
 // Static functions : prototype
@@ -272,6 +273,12 @@ static s3fs_log_level bumpup_s3fs_log_level(void)
 
 static bool is_special_name_folder_object(const char* path)
 {
+  if(!support_compat_dir){
+    // s3fs does not support compatibility directory type("_$folder$" etc) now,
+    // thus always returns false.
+    return false;
+  }
+
   if(!path || '\0' == path[0]){
     return false;
   }
@@ -327,7 +334,7 @@ static int chk_dir_object_type(const char* path, string& newpath, string& nowpat
   if(0 == (result = get_object_attribute(newpath.c_str(), NULL, pmeta, false, &isforce))){
     // Found "dir/" cache --> Check for "_$folder$", "no dir object"
     nowcache = newpath;
-    if(is_special_name_folder_object(newpath.c_str())){
+    if(is_special_name_folder_object(newpath.c_str())){     // check support_compat_dir in this function
       // "_$folder$" type.
       (*pType) = DIRTYPE_FOLDER;
       nowpath = newpath.substr(0, newpath.length() - 1) + "_$folder$"; // cut and add
@@ -345,8 +352,8 @@ static int chk_dir_object_type(const char* path, string& newpath, string& nowpat
         (*pType) = DIRTYPE_OLD;
       }
     }
-  }else{
+  }else if(support_compat_dir){
-    // Check "dir"
+    // Check "dir" when support_compat_dir is enabled
     nowpath = newpath.substr(0, newpath.length() - 1);
     if(0 == (result = get_object_attribute(nowpath.c_str(), NULL, pmeta, false, &isforce))){
       // Found "dir" cache --> this case is only "dir" type.
@@ -361,6 +368,7 @@ static int chk_dir_object_type(const char* path, string& newpath, string& nowpat
       }
     }else{
       // Not found cache --> check for "_$folder$" and "no dir object".
+      // (come here is that support_compat_dir is enabled)
       nowcache = "";  // This case is no cache.
       nowpath += "_$folder$";
       if(is_special_name_folder_object(nowpath.c_str())){
@@ -424,7 +432,7 @@ static int get_object_attribute(const char* path, struct stat* pstbuf, headers_t
   pisforce    = (NULL != pisforce ? pisforce : &forcedir);
   (*pisforce) = false;
   strpath     = path;
-  if(overcheck && string::npos != (Pos = strpath.find("_$folder$", 0))){
+  if(support_compat_dir && overcheck && string::npos != (Pos = strpath.find("_$folder$", 0))){
     strpath = strpath.substr(0, Pos);
     strpath += "/";
   }
@@ -445,13 +453,14 @@ static int get_object_attribute(const char* path, struct stat* pstbuf, headers_t
   // if not found target path object, do over checking
   if(0 != result){
     if(overcheck){
-      if('/' != strpath[strpath.length() - 1]){
+      // when support_compat_dir is disabled, strpath maybe have "_$folder$".
+      if('/' != strpath[strpath.length() - 1] && string::npos == strpath.find("_$folder$", 0)){
         // now path is "object", do check "object/" for over checking
         strpath    += "/";
         result      = s3fscurl.HeadRequest(strpath.c_str(), (*pheader));
         s3fscurl.DestroyCurlHandle();
       }
-      if(0 != result){
+      if(support_compat_dir && 0 != result){
         // now path is "object/", do check "object_$folder$" for over checking
         strpath     = strpath.substr(0, strpath.length() - 1);
         strpath    += "_$folder$";
@@ -466,7 +475,7 @@ static int get_object_attribute(const char* path, struct stat* pstbuf, headers_t
         }
       }
     }
-    if(0 != result && string::npos == strpath.find("_$folder$", 0)){
+    if(support_compat_dir && 0 != result && string::npos == strpath.find("_$folder$", 0)){
       // now path is "object" or "object/", do check "no dir object" which is not object but has only children.
       if('/' == strpath[strpath.length() - 1]){
         strpath = strpath.substr(0, strpath.length() - 1);
@@ -479,7 +488,7 @@ static int get_object_attribute(const char* path, struct stat* pstbuf, headers_t
       }
     }
   }else{
-    if('/' != strpath[strpath.length() - 1] && string::npos == strpath.find("_$folder$", 0) && is_need_check_obj_detail(*pheader)){
+    if(support_compat_dir && '/' != strpath[strpath.length() - 1] && string::npos == strpath.find("_$folder$", 0) && is_need_check_obj_detail(*pheader)){
       // check a case of that "object" does not have attribute and "object" is possible to be directory.
       if(-ENOTEMPTY == directory_empty(strpath.c_str())){
         // found "no dir object".
@@ -4666,6 +4675,10 @@ static int my_fuse_opt_proc(void* data, const char* arg, int key, struct fuse_ar
       complement_stat = true;
       return 0;
     }
+    if(0 == strcmp(arg, "notsup_compat_dir")){
+      support_compat_dir = false;
+      return 0;
+    }
     if(0 == strcmp(arg, "enable_content_md5")){
       S3fsCurl::SetContentMd5(true);
       return 0;

src/s3fs_util.cpp

@@ -1221,6 +1221,24 @@ void show_help (void)
     "        for a object, then the object will not be able to be allowed to\n"
     "        list/modify.\n"
     "\n"
+    "   notsup_compat_dir (not support compatibility directory types)\n"
+    "        As a default, s3fs supports objects of the directory type as\n"
+    "        much as possible and recognizes them as directories.\n"
+    "        Objects that can be recognized as directory objects are \"dir/\",\n"
+    "        \"dir\", \"dir_$folder$\", and there is a file object that does\n"
+    "        not have a directory object but contains that directory path.\n"
+    "        s3fs needs redundant communication to support all these\n"
+    "        directory types. The object as the directory created by s3fs\n"
+    "        is \"dir/\". By restricting s3fs to recognize only \"dir/\" as\n"
+    "        a directory, communication traffic can be reduced. This option\n"
+    "        is used to give this restriction to s3fs.\n"
+    "        However, if there is a directory object other than \"dir/\" in\n"
+    "        the bucket, specifying this option is not recommended. s3fs may\n"
+    "        not be able to recognize the object correctly if an object\n"
+    "        created by s3fs exists in the bucket.\n"
+    "        Please use this option when the directory in the bucket is\n"
+    "        only \"dir/\" object.\n"
+    "\n"
     "FUSE/mount Options:\n"
     "\n"
     "   Most of the generic mount options described in 'man mount' are\n"