add epall and eprand policies

README.md

@@ -1,6 +1,6 @@
 % mergerfs(1) mergerfs user manual
 % Antonio SJ Musumeci <trapexit@spawn.link>
-% 2016-05-17
+% 2016-08-01
 
 # NAME
 
@@ -86,10 +86,12 @@ Due to FUSE limitations **ioctl** behaves differently if its acting on a directo
 | Policy | Description |
 |--------------|-------------|
 | all | Search category: acts like **ff**. Action category: apply to all found. Create category: for **mkdir**, **mknod**, and **symlink** it will apply to all found. **create** works like **ff**. It will exclude readonly drives and those with free space less than **minfreespace**. |
+| epall (existing path, all) | Search category: acts like **epff**. Action category: apply to all found. Create category: for **mkdir**, **mknod**, and **symlink** it will apply to all existing paths found. **create** works like **epff**. It will exclude readonly drives and those with free space less than **minfreespace**. |
 | epff | Given the order of the drives, as defined at mount time or when configured via the xattr interface, act on the first one found where the path already exists. For **create** cateogry it will exclude readonly drives and those with free space less than **minfreespace** (unless there is no other option). Falls back to **ff**. |
 | eplfs (existing path, least free space) | If the path exists on multiple drives use the one with the least free space. For **create** category it will exclude readonly drives and those with free space less than **minfreespace**. Falls back to **lfs**. |
 | eplus (existing path, least used space) | If the path exists on multiple drives the the one with the least used space. For **create** category it will exclude readonly drives and those with free space less than **minfreespace**. Falls back to **lus**. |
 | epmfs (existing path, most free space) | If the path exists on multiple drives use the one with the most free space. For **create** category it will exclude readonly drives and those with free space less than **minfreespace**. Falls back to **mfs**. |
+| eprand (existing path, random) | Calls **epall** and then randomizes. |
 | erofs | Exclusively return **-1** with **errno** set to **EROFS**. By setting **create** functions to this you can in effect turn the filesystem readonly. |
 | ff (first found) | Given the order of the drives, as defined at mount time or when configured via xattr interface, act on the first one found. For **create** category it will exclude readonly drives and those with free space less than **minfreespace** (unless there is no other option). |
 | lfs (least free space) | Pick the drive with the least available free space. For **create** category it will exclude readonly drives and those with free space less than **minfreespace**. Falls back to **mfs**. |

man/mergerfs.1

@@ -1,5 +1,5 @@
 .\"t
-.TH "mergerfs" "1" "2016\-05\-17" "mergerfs user manual" ""
+.TH "mergerfs" "1" "2016\-08\-01" "mergerfs user manual" ""
 .SH NAME
 .PP
 mergerfs \- another (FUSE based) union filesystem
@@ -8,7 +8,7 @@ mergerfs \- another (FUSE based) union filesystem
 mergerfs \-o<options> <srcmounts> <mountpoint>
 .SH DESCRIPTION
 .PP
-\f[B]mergerfs\f[] is a union filesystem geared towards simplifing
+\f[B]mergerfs\f[] is a union filesystem geared towards simplifying
 storage and management of files across numerous commodity storage
 devices.
 It is similar to \f[B]mhddfs\f[], \f[B]unionfs\f[], and \f[B]aufs\f[].
@@ -30,7 +30,8 @@ Opportunistic credential caching
 .IP \[bu] 2
 Works with heterogeneous filesystem types
 .IP \[bu] 2
-Handling of writes to full drives
+Handling of writes to full drives (transparently move file to drive with
+capacity)
 .IP \[bu] 2
 Handles pool of readonly and read/write drives
 .SH OPTIONS
@@ -203,6 +204,17 @@ It will exclude readonly drives and those with free space less than
 \f[B]minfreespace\f[].
 T}
 T{
+epall (existing path, all)
+T}@T{
+Search category: acts like \f[B]epff\f[].
+Action category: apply to all found.
+Create category: for \f[B]mkdir\f[], \f[B]mknod\f[], and
+\f[B]symlink\f[] it will apply to all existing paths found.
+\f[B]create\f[] works like \f[B]epff\f[].
+It will exclude readonly drives and those with free space less than
+\f[B]minfreespace\f[].
+T}
+T{
 epff
 T}@T{
 Given the order of the drives, as defined at mount time or when
@@ -241,6 +253,11 @@ with free space less than \f[B]minfreespace\f[].
 Falls back to \f[B]mfs\f[].
 T}
 T{
+eprand (existing path, random)
+T}@T{
+Calls \f[B]epall\f[] and then randomizes.
+T}
+T{
 erofs
 T}@T{
 Exclusively return \f[B]\-1\f[] with \f[B]errno\f[] set to

src/policy.cpp

@@ -30,10 +30,12 @@ namespace mergerfs
     buildvector<Policy,true>
     (POLICY(invalid,DOESNT_PRESERVE_PATH))
     (POLICY(all,DOESNT_PRESERVE_PATH))
+    (POLICY(epall,PRESERVES_PATH))
     (POLICY(epff,PRESERVES_PATH))
     (POLICY(eplfs,PRESERVES_PATH))
     (POLICY(eplus,PRESERVES_PATH))
     (POLICY(epmfs,PRESERVES_PATH))
+    (POLICY(eprand,PRESERVES_PATH))
     (POLICY(erofs,DOESNT_PRESERVE_PATH))
     (POLICY(ff,DOESNT_PRESERVE_PATH))
     (POLICY(lfs,DOESNT_PRESERVE_PATH))
@@ -48,10 +50,12 @@ namespace mergerfs
 
   CONST_POLICY(invalid);
   CONST_POLICY(all);
+  CONST_POLICY(epall);
   CONST_POLICY(epff);
   CONST_POLICY(eplfs);
   CONST_POLICY(eplus);
   CONST_POLICY(epmfs);
+  CONST_POLICY(eprand);
   CONST_POLICY(erofs);
   CONST_POLICY(ff);
   CONST_POLICY(lfs);

src/policy.hpp

@@ -43,10 +43,12 @@ namespace mergerfs
           invalid = -1,
           BEGIN   = 0,
           all     = BEGIN,
+          epall,
           epff,
           eplfs,
           eplus,
           epmfs,
+          eprand,
           erofs,
           ff,
           lfs,
@@ -97,10 +99,12 @@ namespace mergerfs
 
       static int invalid(CType,cstrvec&,const char *,cuint64_t,cstrptrvec&);
       static int all(CType,cstrvec&,const char*,cuint64_t,cstrptrvec&);
+      static int epall(CType,cstrvec&,const char*,cuint64_t,cstrptrvec&);
       static int epff(CType,cstrvec&,const char *,cuint64_t,cstrptrvec&);
       static int eplfs(CType,cstrvec&,const char *,cuint64_t,cstrptrvec&);
       static int eplus(CType,cstrvec&,const char *,cuint64_t,cstrptrvec&);
       static int epmfs(CType,cstrvec&,const char *,cuint64_t,cstrptrvec&);
+      static int eprand(CType,cstrvec&,const char *,cuint64_t,cstrptrvec&);
       static int erofs(CType,cstrvec&,const char *,cuint64_t,cstrptrvec&);
       static int ff(CType,cstrvec&,const char *,cuint64_t,cstrptrvec&);
       static int lfs(CType,cstrvec&,const char *,cuint64_t,cstrptrvec&);
@@ -171,10 +175,12 @@ namespace mergerfs
 
     static const Policy &invalid;
     static const Policy &all;
+    static const Policy &epall;
     static const Policy &epff;
     static const Policy &eplfs;
     static const Policy ⩱
     static const Policy &epmfs;
+    static const Policy &eprand;
     static const Policy &erofs;
     static const Policy &ff;
     static const Policy &lfs;

src/policy_epall.cpp

@@ -0,0 +1,105 @@
+/*
+  Copyright (c) 2016, Antonio SJ Musumeci <trapexit@spawn.link>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include <errno.h>
+
+#include <string>
+#include <vector>
+
+#include "fs.hpp"
+#include "fs_path.hpp"
+#include "policy.hpp"
+
+using std::string;
+using std::vector;
+
+static
+int
+_epall_create(const vector<string>  &basepaths,
+              const char            *fusepath,
+              const uint64_t         minfreespace,
+              vector<const string*> &paths)
+{
+  string fullpath;
+
+  for(size_t i = 0, ei = basepaths.size(); i != ei; i++)
+    {
+      bool readonly;
+      uint64_t spaceavail;
+      uint64_t _spaceused;
+      const string *basepath = &basepaths[i];
+
+      fs::path::make(basepath,fusepath,fullpath);
+
+      if(!fs::exists(fullpath))
+        continue;
+      if(!fs::info(*basepath,readonly,spaceavail,_spaceused))
+        continue;
+      if(readonly)
+        continue;
+      if(spaceavail < minfreespace)
+        continue;
+
+      paths.push_back(basepath);
+    }
+
+  if(paths.empty())
+    return POLICY_FAIL_ENOENT;
+
+  return POLICY_SUCCESS;
+}
+
+static
+int
+_epall_other(const vector<string>  &basepaths,
+             const char            *fusepath,
+             vector<const string*> &paths)
+{
+  string fullpath;
+
+  for(size_t i = 0, ei = basepaths.size(); i != ei; i++)
+    {
+      const string *basepath = &basepaths[i];
+
+      fs::path::make(basepath,fusepath,fullpath);
+
+      if(!fs::exists(fullpath))
+        continue;
+
+      paths.push_back(basepath);
+    }
+
+  if(paths.empty())
+    return POLICY_FAIL_ENOENT;
+
+  return POLICY_SUCCESS;
+}
+
+namespace mergerfs
+{
+  int
+  Policy::Func::epall(const Category::Enum::Type  type,
+                      const vector<string>       &basepaths,
+                      const char                 *fusepath,
+                      const uint64_t              minfreespace,
+                      vector<const string*>      &paths)
+  {
+    if(type == Category::Enum::create)
+      return _epall_create(basepaths,fusepath,minfreespace,paths);
+
+    return _epall_other(basepaths,fusepath,paths);
+  }
+}

src/policy_eprand.cpp

@@ -0,0 +1,46 @@
+/*
+  Copyright (c) 2016, Antonio SJ Musumeci <trapexit@spawn.link>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include <errno.h>
+
+#include <string>
+#include <vector>
+#include <algorithm>
+
+#include "policy.hpp"
+#include "success_fail.hpp"
+
+using std::string;
+using std::vector;
+
+namespace mergerfs
+{
+  int
+  Policy::Func::eprand(const Category::Enum::Type  type,
+                       const vector<string>       &basepaths,
+                       const char                 *fusepath,
+                       const uint64_t              minfreespace,
+                       vector<const string*>      &paths)
+  {
+    int rv;
+
+    rv = Policy::Func::epall(type,basepaths,fusepath,minfreespace,paths);
+    if(POLICY_SUCCEEDED(rv))
+      std::random_shuffle(paths.begin(),paths.end());
+
+    return rv;
+  }
+}