Add 2 options --noattrcache --nodatacache (#500)

--nocache : disables attr and data cache.
--noattrcache : disables attr cache only.
--nodatacache : disables data cache only.

encfs/encfs.pod

@@ -21,7 +21,7 @@ B<encfs> [B<--version>] [B<-v>|B<--verbose>] [B<-c>|B<--config>] [B<-t>|B<--sysl
 [B<--reverse>] [B<--reversewrite>] [B<--extpass=program>] [B<-S>|B<--stdinpass>] 
 [B<--anykey>] [B<--forcedecode>] [B<-require-macs>] 
 [B<-i MINUTES>|B<--idle=MINUTES>] [B<-m>|B<--ondemand>] [B<--delaymount>] [B<-u>|B<--unmount>] 
-[B<--public>] [B<--nocache>] [B<--no-default-flags>]
+[B<--public>] [B<--nocache>] [B<--noattrcache>] [B<--nodatacache>] [B<--no-default-flags>]
 [B<-o FUSE_OPTION>] [B<-d>|B<--fuse-debug>] [B<-H>|B<--fuse-help>] 
 I<rootdir> I<mountPoint> 
 [B<--> [I<Fuse Mount Options>]]
@@ -238,9 +238,17 @@ you want before considering the use of B<--public>.
 
 Disable the kernel's cache of file attributes.
 Setting this option makes EncFS pass "attr_timeout=0" and "entry_timeout=0" to
-FUSE. This makes sure that modifications to the backing files that occour
-outside EncFS show up immediately in the EncFS mount. The main use case
-for "--nocache" is reverse mode.
+FUSE. This makes sure that modifications to the backing file attributes that
+occour outside EncFS show up immediately in the EncFS mount. The internal EncFS
+data cache is also disabled. The main use case for B<--nocache> is reverse mode.
+
+=item B<--noattrcache>
+
+Same as B<--nocache> but for attributes only.
+
+=item B<--nodatacache>
+
+Same as B<--nocache> but for data only.
 
 =item B<--no-default-flags>
 

encfs/main.cpp

@@ -47,8 +47,10 @@
  * not have a short version */
 #define LONG_OPT_ANNOTATE 513
 #define LONG_OPT_NOCACHE 514
-#define LONG_OPT_REQUIRE_MAC 515
-#define LONG_OPT_INSECURE 516
+#define LONG_OPT_NODATACACHE 515
+#define LONG_OPT_NOATTRCACHE 516
+#define LONG_OPT_REQUIRE_MAC 517
+#define LONG_OPT_INSECURE 518
 
 using namespace std;
 using namespace encfs;
@@ -254,7 +256,9 @@ static bool processArgs(int argc, char *argv[],
       {"syslogtag", 1, nullptr, 't'},  // syslog tag
       {"annotate", 0, nullptr,
        LONG_OPT_ANNOTATE},  // Print annotation lines to stderr
-      {"nocache", 0, nullptr, LONG_OPT_NOCACHE},  // disable caching
+      {"nocache", 0, nullptr, LONG_OPT_NOCACHE},         // disable all caching
+      {"nodatacache", 0, nullptr, LONG_OPT_NODATACACHE}, // disable data caching
+      {"noattrcache", 0, nullptr, LONG_OPT_NOATTRCACHE}, // disable attr caching
       {"verbose", 0, nullptr, 'v'},               // verbose mode
       {"version", 0, nullptr, 'V'},               // version
       {"reverse", 0, nullptr, 'r'},               // reverse encryption
@@ -384,6 +388,16 @@ static bool processArgs(int argc, char *argv[],
         // Should be enforced due to attr_timeout=0, but does not seem to work correctly
         // https://github.com/billziss-gh/winfsp/issues/155
         PUSHARG("-oFileInfoTimeout=0");
+#endif
+        break;
+      case LONG_OPT_NODATACACHE:
+        out->opts->noCache = true;
+        break;
+      case LONG_OPT_NOATTRCACHE:
+        PUSHARG("-oattr_timeout=0");
+        PUSHARG("-oentry_timeout=0");
+#ifdef __CYGWIN__
+        PUSHARG("-oFileInfoTimeout=0");
 #endif
         break;
       case 'm':

integration/reverse.t.pl

@@ -90,7 +90,7 @@ sub mount
     ok(waitForFile("$plain/.encfs6.xml"), "plain .encfs6.xml exists") or BAIL_OUT("'$plain/.encfs6.xml'");
     my $e = encName(".encfs6.xml");
     ok(waitForFile("$ciphertext/$e"), "encrypted .encfs6.xml exists") or BAIL_OUT("'$ciphertext/$e'");
-    system("ENCFS6_CONFIG=$plain/.encfs6.xml ./build/encfs --nocache --extpass=\"echo test\" $ciphertext $decrypted");
+    system("ENCFS6_CONFIG=$plain/.encfs6.xml ./build/encfs --noattrcache --nodatacache --extpass=\"echo test\" $ciphertext $decrypted");
     ok(waitForFile("$decrypted/.encfs6.xml"), "decrypted .encfs6.xml exists") or BAIL_OUT("'$decrypted/.encfs6.xml'");
 }