provide empty filesystem

CMakeLists.txt

@@ -9,6 +9,7 @@ pkg_check_modules(LWS REQUIRED IMPORTED_TARGET libwebsockets)
 
 add_library(webfuse_static STATIC
     src/webfuse/webfuse.cpp
+    src/webfuse/fuse.cpp
     src/webfuse/filesystem/status.cpp
     src/webfuse/filesystem/accessmode.cpp
     src/webfuse/filesystem/openflags.cpp
@@ -17,6 +18,8 @@ add_library(webfuse_static STATIC
     src/webfuse/filesystem/filemode.cpp
     src/webfuse/filesystem/filetime.cpp
     src/webfuse/filesystem/fileattributes.cpp
+    src/webfuse/filesystem/filesystem_statistics.cpp
+    src/webfuse/filesystem/empty_filesystem.cpp
 )
 
 target_include_directories(webfuse_static PUBLIC src)

src/main.cpp

@@ -2,6 +2,6 @@
 
 int main(int argc, char* argv[])
 {
-    webfuse::app app(argc, argv);
-    return app.run();
+    webfuse::app app;
+    return app.run(argc, argv);
 }

src/webfuse/filesystem/empty_filesystem.cpp

@@ -0,0 +1,135 @@
+#include "webfuse/filesystem/empty_filesystem.hpp"
+
+namespace webfuse
+{
+
+status empty_filesystem::access(std::string const & path, access_mode mode)
+{
+    if (path == "/")
+    {
+        return status::good;
+    }
+    else
+    {
+        return status::bad_enoent;
+    }
+}
+
+status empty_filesystem::getattr(std::string const & path, file_attributes & attr)
+{
+    if (path == "/")
+    {
+        attr.inode = 1;
+        attr.nlink = 1;
+        attr.mode = filemode(filemode::dir | 0x444);
+        return status::good;
+    }
+    else
+    {
+        return status::bad_enoent;
+    }
+}
+
+status empty_filesystem::readlink(std::string const & path, std::string & out)
+{
+    return status::bad_enoent;
+}
+
+status empty_filesystem::symlink(std::string const & target, std::string const & linkpath)
+{
+    return status::bad_enoent;
+}
+
+status empty_filesystem::link(std::string const & old_path, std::string const & new_path)
+{
+    return status::bad_enoent;
+}
+
+status empty_filesystem::rename(std::string const & old_path, std::string const & new_path)
+{
+    return status::bad_enoent;
+}
+
+status empty_filesystem::chmod(std::string const & path, filemode mode)
+{
+    return status::bad_eperm;
+}
+
+status empty_filesystem::chown(std::string const & path, user_id uid, group_id gid)
+{
+    return status::bad_eperm;
+}
+
+status empty_filesystem::truncate(std::string const & path, uint64_t offset, filehandle handle)
+{
+    return status::bad_eperm;
+}
+
+status empty_filesystem::fsync(std::string const & path, bool is_datasync, filehandle handle)
+{
+    return status::good;
+}
+
+status empty_filesystem::open(std::string const & path, openflags flags, filehandle & handle)
+{
+    return status::bad_enoent;
+}
+
+status empty_filesystem::mknod(std::string const & path, filemode mode, uint64_t rdev)
+{
+    return status::bad_eperm;
+
+}
+status empty_filesystem::create(std::string const & path, filemode mode, filehandle & handle)
+{
+    return status::bad_eperm;
+}
+
+status empty_filesystem::release(std::string const & path, filehandle handle)
+{
+    return status::good;
+}
+
+status empty_filesystem::unlink(std::string const & path)
+{
+    return status::bad_eperm;
+}
+
+status empty_filesystem::read(std::string const & path, char * buffer, size_t buffer_size, uint64_t offset, filehandle handle)
+{
+    return status::bad_ebadf;
+}
+status empty_filesystem::write(std::string const & path, char const * buffer, size_t buffer_size, uint64_t offset, filehandle handle)
+{
+    return status::bad_ebadf;
+}
+
+status empty_filesystem::mkdir(std::string const & path, filemode mode)
+{
+    return status::bad_eperm;
+}
+
+status empty_filesystem::readdir(std::string const & path, std::vector<std::string> & entries, filehandle handle)
+{
+    if (path == "/")
+    {
+        return status::good;
+    }
+    else
+    {
+        return status::bad_enoent;
+    }
+}
+
+status empty_filesystem::rmdir(std::string const & path)
+{
+    return status::bad_eperm;
+}
+
+status empty_filesystem::statfs(std::string const & path, filesystem_statistics & statistics)
+{
+    return status::bad_enosys;
+}
+
+
+}

src/webfuse/filesystem/empty_filesystem.hpp

@@ -0,0 +1,45 @@
+#ifndef WEBFUSE_EMPTYFILESYSTEM_HPP
+#define WEBFUSE_EMPTYFILESYSTEM_HPP
+
+#include "webfuse/filesystem/filesystem_i.hpp"
+
+namespace webfuse
+{
+
+class empty_filesystem: public filesystem_i
+{
+public:
+    ~empty_filesystem() override = default;
+
+    status access(std::string const & path, access_mode mode) override;
+    status getattr(std::string const & path, file_attributes & attr) override;
+
+    status readlink(std::string const & path, std::string & out) override;
+    status symlink(std::string const & target, std::string const & linkpath) override;
+    status link(std::string const & old_path, std::string const & new_path) override;
+
+    status rename(std::string const & old_path, std::string const & new_path) override;
+    status chmod(std::string const & path, filemode mode) override;
+    status chown(std::string const & path, user_id uid, group_id gid) override;
+    status truncate(std::string const & path, uint64_t offset, filehandle handle) override;
+    status fsync(std::string const & path, bool is_datasync, filehandle handle) override;
+
+    status open(std::string const & path, openflags flags, filehandle & handle) override;
+    status mknod(std::string const & path, filemode mode, uint64_t rdev) override;
+    status create(std::string const & path, filemode mode, filehandle & handle) override;
+    status release(std::string const & path, filehandle handle) override;
+    status unlink(std::string const & path) override;
+
+    status read(std::string const & path, char * buffer, size_t buffer_size, uint64_t offset, filehandle handle) override;
+    status write(std::string const & path, char const * buffer, size_t buffer_size, uint64_t offset, filehandle handle) override;
+
+    status mkdir(std::string const & path, filemode mode) override;
+    status readdir(std::string const & path, std::vector<std::string> & entries, filehandle handle) override;
+    status rmdir(std::string const & path) override;
+
+    status statfs(std::string const & path, filesystem_statistics & statistics) override;
+};
+
+}
+
+#endif

src/webfuse/filesystem/filesystem_i.hpp

@@ -32,7 +32,7 @@ public:
 
     virtual status rename(std::string const & old_path, std::string const & new_path) = 0;
     virtual status chmod(std::string const & path, filemode mode) = 0;
-    virtual status chown(std::string const & path, user_id uid, group_id gid);
+    virtual status chown(std::string const & path, user_id uid, group_id gid) = 0;
     virtual status truncate(std::string const & path, uint64_t offset, filehandle handle) = 0;
     virtual status fsync(std::string const & path, bool is_datasync, filehandle handle) = 0;
 
@@ -45,7 +45,8 @@ public:
     virtual status read(std::string const & path, char * buffer, size_t buffer_size, uint64_t offset, filehandle handle) = 0;
     virtual status write(std::string const & path, char const * buffer, size_t buffer_size, uint64_t offset, filehandle handle) = 0;
 
-    virtual status readdir(std::string const & path, std::vector<std::string> entries, filehandle handle) = 0;
+    virtual status mkdir(std::string const & path, filemode mode) = 0;
+    virtual status readdir(std::string const & path, std::vector<std::string> & entries, filehandle handle) = 0;
     virtual status rmdir(std::string const & path) = 0;
 
     virtual status statfs(std::string const & path, filesystem_statistics & statistics) = 0;

src/webfuse/filesystem/filesystem_statistics.cpp

@@ -0,0 +1,43 @@
+#include "webfuse/filesystem/filesystem_statistics.hpp"
+
+namespace webfuse
+{
+
+filesystem_statistics::filesystem_statistics()
+: bsize(0)
+, frsize(0)
+, blocks(0)
+, bfree(0)
+, bavail(0)
+, files(0)
+, ffree(0)
+, f_namemax(0)
+{
+
+}
+
+filesystem_statistics::filesystem_statistics(struct statvfs const & other)
+{
+    bsize = other.f_bsize;
+    frsize = other.f_frsize;
+    blocks = other.f_blocks;
+    bfree = other.f_bfree;
+    bavail = other.f_bavail;
+    files = other.f_files;
+    ffree = other.f_ffree;
+    f_namemax = other.f_namemax;
+}
+
+void filesystem_statistics::copy_to(struct statvfs & other) const
+{
+    other.f_bsize = bsize;
+    other.f_frsize = frsize;
+    other.f_blocks = blocks;
+    other.f_bfree = bfree;
+    other.f_bavail = bavail;
+    other.f_files = files;
+    other.f_ffree = ffree;
+    other.f_namemax = f_namemax;
+}
+
+}

src/webfuse/filesystem/status.cpp

@@ -117,4 +117,10 @@ int status::to_fusestatus() const
     }
 }
 
+bool status::is_good() const
+{
+    return (value_ == status::good);
+}
+
+
 }

src/webfuse/filesystem/status.hpp

@@ -53,6 +53,8 @@ public:
 
     static status from_fusestatus(int value);
     int to_fusestatus() const;
+
+    bool is_good() const;
 private:
     int32_t value_;
 };

src/webfuse/fuse.cpp

@@ -0,0 +1,319 @@
+#define FUSE_USE_VERSION 31
+
+#include "webfuse/fuse.hpp"
+#include <fuse.h>
+#include <cstring>
+#include <cstdio>
+
+extern "C"
+{
+
+static webfuse::filesystem_i * fs_get_filesystem()
+{
+    struct fuse_context * context = fuse_get_context();
+    void * private_data = context->private_data;
+    return reinterpret_cast<webfuse::filesystem_i*>(private_data);
+}
+
+static webfuse::filehandle fs_get_handle(fuse_file_info * info)
+{
+    return (nullptr != info) ? info->fh : webfuse::invalid_handle;
+}
+
+static void * fs_init(fuse_conn_info * connection, fuse_config * config)
+{
+    (void) connection;
+    config->use_ino = 1;
+    config->entry_timeout = 0;
+    config->attr_timeout = 0;
+    config->negative_timeout = 0;
+
+    struct fuse_context * context = fuse_get_context();
+    return context->private_data;
+}
+
+
+static int fs_access(char const * path, int raw_mode)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const mode = webfuse::access_mode::from_int(raw_mode);
+    auto const result = fs->access(path, mode);
+
+    return result.to_fusestatus();
+}
+
+static int fs_getattr(char const * path, struct stat * buffer, fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    webfuse::file_attributes attributes(*buffer);
+
+    auto const result = fs->getattr(path, attributes);
+    attributes.to_stat(*buffer);
+
+    return result.to_fusestatus();
+}
+
+static int fs_readlink(char const * path, char * buffer, size_t buffer_size)
+{
+    auto * const fs = fs_get_filesystem();
+
+    std::string out;
+    auto result = fs->readlink(path, out);
+    if (webfuse::status::good == result)
+    {
+        snprintf(buffer, buffer_size, "%s", out.c_str());
+        result = strlen(buffer);
+    }
+
+    return result.to_fusestatus();
+}
+
+static int fs_symlink(char const * target, char const * linkpath)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const result = fs->symlink(target, linkpath);
+    return result.to_fusestatus();
+}
+
+static int fs_link(char const * old_path, char const * new_path)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const result = fs->link(old_path, new_path);
+    return result.to_fusestatus();
+}
+
+static int fs_rename(char const * from, char const * to, unsigned int flags)
+{
+    // ToDo: provide flags 
+    auto * const fs = fs_get_filesystem();
+    auto const result = fs->rename(from, to);
+    return result.to_fusestatus();
+}
+
+static int fs_chmod(char const * path, mode_t raw_mode, fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const mode = webfuse::filemode::from_mode(raw_mode);
+    auto const result = fs->chmod(path, mode);
+    return result.to_fusestatus();
+}
+
+static int fs_chown(char const * path, uid_t raw_uid, 
+    gid_t raw_gid, fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const uid = webfuse::user_id::from_uid(raw_uid);
+    auto const gid = webfuse::group_id::from_gid(raw_gid);
+    auto const result = fs->chown(path, uid, gid);
+    return result.to_fusestatus();
+}
+
+static int fs_truncate(char const * path, off_t raw_size, fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const size = static_cast<uint64_t>(raw_size);
+    auto const handle = fs_get_handle(info);
+
+    auto const result = fs->truncate(path, size, handle);
+    return result.to_fusestatus();
+}
+
+static int fs_fsync(char const * path, int isdatasync, fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    bool const is_datasync = (is_datasync != 0);
+    auto const handle = fs_get_handle(info);
+
+    auto const result = fs->fsync(path, is_datasync, handle);
+    return result.to_fusestatus();
+}
+
+static int fs_open(char const * path, fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const flags = webfuse::openflags::from_int(info->flags);
+
+    auto const result = fs->open(path, flags, info->fh);
+    return result.to_fusestatus();
+}
+
+static int fs_mknod(char const * path, mode_t raw_mode, dev_t raw_rdev)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const mode = webfuse::filemode::from_mode(raw_mode);
+    auto const rdev = static_cast<uint64_t>(raw_rdev);
+
+    auto const result = fs->mknod(path, mode, rdev);
+    return result.to_fusestatus();
+}
+
+static int fs_create(char const * path, mode_t raw_mode, fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const mode = webfuse::filemode::from_mode(raw_mode);
+
+    auto const result = fs->create(path, mode, info->fh);
+    return result.to_fusestatus();
+}
+
+static int fs_release(char const * path, fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const handle = fs_get_handle(info);
+
+    auto const result = fs->release(path, handle);
+    return result.to_fusestatus();
+}
+
+static int fs_unlink(char const * path)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const result = fs->unlink(path);
+    return result.to_fusestatus();
+}
+
+static int fs_read(char const * path, char * buffer,
+    size_t buffer_size, off_t raw_offset,
+    fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const offset = static_cast<uint64_t>(raw_offset);
+    auto const handle = fs_get_handle(info);
+
+    auto const result = fs->read(path, buffer, buffer_size, offset, handle);
+    return result.to_fusestatus();
+}
+
+static int fs_write(char const * path, char const * buffer,
+    size_t buffer_size, off_t raw_offset,
+    fuse_file_info * info)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const offset = static_cast<uint64_t>(raw_offset);
+    auto const handle = fs_get_handle(info);
+
+    auto const result = fs->write(path, buffer, buffer_size, offset, handle);
+    return result.to_fusestatus();
+}
+
+static int fs_mkdir(char const * path, mode_t raw_mode)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const mode = webfuse::filemode::from_mode(raw_mode);
+
+    auto const result = fs->mkdir(path, mode);
+    return result.to_fusestatus();
+}
+
+static int fs_readdir(char const * path, void * buffer, 
+    fuse_fill_dir_t filler, off_t offset, fuse_file_info * info,
+    fuse_readdir_flags flags)
+{
+    auto * const fs = fs_get_filesystem();
+    auto handle = fs_get_handle(info);
+    std::vector<std::string> names;
+    auto const result = fs->readdir(path, names, handle);
+    if (result.is_good())
+    {
+        filler(buffer, ".", nullptr, 0, static_cast<fuse_fill_dir_flags>(0));
+        filler(buffer, "..", nullptr, 0, static_cast<fuse_fill_dir_flags>(0));
+        for (auto const & name: names)
+        {
+            filler(buffer, name.c_str(), nullptr, 0, static_cast<fuse_fill_dir_flags>(0));
+        }
+    }
+
+    return result.to_fusestatus();
+}
+
+static int fs_rmdir(char const * path)
+{
+    auto * const fs = fs_get_filesystem();
+    auto const result = fs->rmdir(path);
+    return result.to_fusestatus();
+}
+
+static int fs_statfs(char const * path, struct statvfs * buffer)
+{
+    auto * const fs = fs_get_filesystem();
+    webfuse::filesystem_statistics statistics(*buffer);
+
+    auto const result = fs->statfs(path, statistics);
+    statistics.copy_to(*buffer);
+
+    return result.to_fusestatus();
+
+}
+
+}
+
+namespace webfuse
+{
+
+class fuse::detail
+{
+public:
+    filesystem_i & filesystem;
+};
+
+fuse::fuse(filesystem_i & filesystem)
+: d(new detail{filesystem})
+{
+
+}
+
+fuse::~fuse()
+{
+    delete d;
+}
+
+fuse::fuse(fuse && other)
+{
+    this->d = other.d;
+    other.d = nullptr;
+}
+
+fuse& fuse::operator=(fuse && other)
+{
+    if (this != &other)
+    {
+        delete d;
+        this->d = other.d;
+        other.d = nullptr;
+    }
+
+    return *this;
+}
+
+int fuse::run(int argc, char * argv[])
+{
+    void * context = reinterpret_cast<void*>(&d->filesystem);
+    struct fuse_operations operations;
+    memset(reinterpret_cast<void*>(&operations), 0, sizeof(operations));
+    operations.init = fs_init;
+    operations.access = fs_access;
+    operations.getattr = fs_getattr;
+    operations.readlink = fs_readlink;
+    operations.symlink = fs_symlink;
+    operations.link = fs_link;
+    operations.rename = fs_rename;
+    operations.chmod = fs_chmod;
+    operations.chown = fs_chown;
+    operations.truncate = fs_truncate;
+    operations.fsync = fs_fsync;
+    operations.open = fs_open;
+    operations.mknod = fs_mknod;
+    operations.create = fs_create;
+    operations.release = fs_release;
+    operations.unlink = fs_unlink;
+    operations.read = fs_read;
+    operations.write = fs_write;
+    operations.mkdir = fs_mkdir;
+    operations.readdir = fs_readdir;
+    operations.rmdir = fs_rmdir;
+    operations.statfs = fs_statfs;
+
+    return fuse_main(argc, argv, &operations, context);
+}
+
+}

src/webfuse/fuse.hpp

@@ -13,9 +13,9 @@ class fuse
 public:
     explicit fuse(filesystem_i & filesystem);
     ~fuse();
-    fuse (fuse &&) = delete;
-    fuse& operator=(fuse &&) = delete;
-    void run(int argc, char * argv[]);
+    fuse (fuse && other);
+    fuse& operator=(fuse && other);
+    int run(int argc, char * argv[]);
 private:
     class detail;
     detail * d;

src/webfuse/webfuse.cpp

@@ -1,27 +1,16 @@
 #include "webfuse/webfuse.hpp"
+#include "webfuse/fuse.hpp"
+#include "webfuse/filesystem/empty_filesystem.hpp"
 
 namespace webfuse
 {
 
-class app::detail
+int app::run(int argc, char * argv[])
 {
-    int dummy;
-};
+    empty_filesystem filesystem;
+    fuse fuse_fs(filesystem);
 
-app::app(int argc, char * argv[])
-: d(new detail)
-{
-
-}
-
-app::~app()
-{
-    delete d;
-}
-
-int app::run()
-{
-    return 0;
+    return fuse_fs.run(argc, argv);
 }
 
 }

src/webfuse/webfuse.hpp

@@ -6,17 +6,8 @@ namespace webfuse
 
 class app
 {
-    app(app const &) = delete;
-    app& operator=(app const &) = delete;
-    app(app &&) = delete;
-    app& operator=(app &&) = delete;
 public:
-    app(int argc, char * argv[]);
-    ~app();
-    int run();
-private:
-    class detail;
-    detail * d;
+    int run(int argc, char * argv[]);
 };
 
 }

test-src/webfuse/test_app.cpp

@@ -3,7 +3,5 @@
 
 TEST(app, init)
 {
-    char args0[] = "webfuse";
-    char * args[] = { args0, nullptr };
-    webfuse::app(1, args);
+    webfuse::app app;
 }