Add readdir policies

src/fuse_readdir_seq.cpp

@@ -0,0 +1,123 @@
+/*
+  Copyright (c) 2019, 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.
+*/
+
+#define _DEFAULT_SOURCE
+
+#include "fuse_readdir_seq.hpp"
+
+#include "branches.hpp"
+#include "config.hpp"
+#include "dirinfo.hpp"
+#include "errno.hpp"
+#include "fs_closedir.hpp"
+#include "fs_devid.hpp"
+#include "fs_dirfd.hpp"
+#include "fs_inode.hpp"
+#include "fs_opendir.hpp"
+#include "fs_path.hpp"
+#include "fs_readdir.hpp"
+#include "fs_stat.hpp"
+#include "hashset.hpp"
+#include "ugid.hpp"
+
+#include "fuse.h"
+#include "fuse_dirents.h"
+
+#include <string>
+#include <vector>
+
+
+namespace l
+{
+  static
+  uint64_t
+  dirent_exact_namelen(const struct dirent *d_)
+  {
+#ifdef _D_EXACT_NAMLEN
+    return _D_EXACT_NAMLEN(d_);
+#elif defined _DIRENT_HAVE_D_NAMLEN
+    return d_->d_namlen;
+#else
+    return strlen(d_->d_name);
+#endif
+  }
+
+  static
+  int
+  readdir(const Branches::CPtr &branches_,
+          const char           *dirname_,
+          fuse_dirents_t       *buf_)
+  {
+    HashSet names;
+    std::string basepath;
+    std::string fullpath;
+
+    fuse_dirents_reset(buf_);
+
+    for(const auto &branch : *branches_)
+      {
+        int rv;
+        DIR *dh;
+        dev_t dev;
+
+        basepath = fs::path::make(branch.path,dirname_);
+
+        dh = fs::opendir(basepath);
+        if(!dh)
+          continue;
+
+        dev = fs::devid(dh);
+
+        rv = 0;
+        for(struct dirent *de = fs::readdir(dh); de && !rv; de = fs::readdir(dh))
+          {
+            std::uint64_t namelen;
+
+            namelen = l::dirent_exact_namelen(de);
+
+            rv = names.put(de->d_name,namelen);
+            if(rv == 0)
+              continue;
+
+            fullpath = fs::path::make(dirname_,de->d_name);
+            de->d_ino = fs::inode::calc(fullpath,
+                                        DTTOIF(de->d_type),
+                                        dev,
+                                        de->d_ino);
+
+            rv = fuse_dirents_add(buf_,de,namelen);
+            if(rv)
+              return (fs::closedir(dh),-ENOMEM);
+          }
+
+        fs::closedir(dh);
+      }
+
+    return 0;
+  }
+}
+
+int
+FUSE::ReadDirSeq::operator()(fuse_file_info_t const *ffi_,
+                             fuse_dirents_t         *buf_)
+{
+  Config::Read        cfg;
+  DirInfo            *di = reinterpret_cast<DirInfo*>(ffi_->fh);
+  const fuse_context *fc = fuse_get_context();
+  const ugid::Set     ugid(fc->uid,fc->gid);
+
+  return l::readdir(cfg->branches,di->fusepath.c_str(),buf_);
+}