aboutsummaryrefslogtreecommitdiff
path: root/src
diff options
context:
space:
mode:
authorGravatar Benjamin Barenblat <bbaren@mit.edu>2016-02-20 14:29:44 -0500
committerGravatar Benjamin Barenblat <bbaren@mit.edu>2016-02-20 14:29:44 -0500
commitb89b485f5accd7707dd95b9748737e12995c169d (patch)
tree40a109bcc88b59f3f74c5be98416c2ec46a0e869 /src
parent5402cf00c99d01474e27d40ed36c88b1f197614b (diff)
Make more exception-safe
Ensure that FUSE callbacks will never throw exceptions. Log unexpected exceptions as errors.
Diffstat (limited to 'src')
-rw-r--r--src/operations.cc127
1 files changed, 71 insertions, 56 deletions
diff --git a/src/operations.cc b/src/operations.cc
index eb96d5f..2154371 100644
--- a/src/operations.cc
+++ b/src/operations.cc
@@ -41,34 +41,34 @@ namespace {
// Pointer to the directory underlying the mount point.
File* root_;
-File* FileInfoFile(fuse_file_info* const file_info) {
+File* FileInfoFile(fuse_file_info* const file_info) noexcept {
return reinterpret_cast<File*>(file_info->fh);
}
-Directory* FileInfoDirectory(fuse_file_info* const file_info) {
+Directory* FileInfoDirectory(fuse_file_info* const file_info) noexcept {
return reinterpret_cast<Directory*>(file_info->fh);
}
-mode_t DirectoryTypeToFileType(const unsigned char type) {
+mode_t DirectoryTypeToFileType(const unsigned char type) noexcept {
return static_cast<mode_t>(DTTOIF(type));
}
-void* Initialize(fuse_conn_info*) {
+void* Initialize(fuse_conn_info*) noexcept {
LOG(INFO) << "initialize";
return nullptr;
}
-void Destroy(void*) { LOG(INFO) << "destroy"; }
+void Destroy(void*) noexcept { LOG(INFO) << "destroy"; }
int Getattr(const char* const path, struct stat* output) noexcept {
- LOG(INFO) << "getattr(" << path << ")";
+ try {
+ LOG(INFO) << "getattr(" << path << ")";
- if (path[0] == '\0') {
- LOG(ERROR) << "getattr called on path not starting with /";
- return -ENOENT;
- }
+ if (path[0] == '\0') {
+ LOG(ERROR) << "getattr called on path not starting with /";
+ return -ENOENT;
+ }
- try {
if (std::strcmp(path, "/") == 0) {
// They're asking for information about the mount point.
*output = root_->Stat();
@@ -81,16 +81,17 @@ int Getattr(const char* const path, struct stat* output) noexcept {
return 0;
} catch (const std::system_error& e) {
return -e.code().value();
+ } catch (...) {
+ LOG(ERROR) << "getattr caught unexpected value";
+ return -ENOTRECOVERABLE;
}
}
-int Open(const char* const path, fuse_file_info* const file_info) {
+int Open(const char* const path, fuse_file_info* const file_info) noexcept {
LOG(INFO) << "open(" << path << ")";
- std::unique_ptr<File> file;
-
try {
- file.reset(new File(
+ std::unique_ptr<File> file(new File(
std::strcmp(path, "/") == 0
?
// They're asking to open the mount point.
@@ -98,84 +99,89 @@ int Open(const char* const path, fuse_file_info* const file_info) {
:
// Trim the leading slash so OpenAt will treat it relative to root_.
root_->OpenAt(path + 1, file_info->flags)));
+
+ static_assert(sizeof(file_info->fh) == sizeof(std::uintptr_t),
+ "FUSE file handles are a different size than pointers");
+ file_info->fh = reinterpret_cast<std::uintptr_t>(file.release());
+ return 0;
} catch (const std::bad_alloc&) {
return -ENOMEM;
} catch (const std::system_error& e) {
return -e.code().value();
+ } catch (...) {
+ LOG(ERROR) << "open caught unexpected value";
+ return -ENOTRECOVERABLE;
}
-
- static_assert(sizeof(file_info->fh) == sizeof(std::uintptr_t),
- "FUSE file handles are a different size than pointers");
- file_info->fh = reinterpret_cast<std::uintptr_t>(file.release());
- return 0;
}
int Create(const char* const path, const mode_t mode,
- fuse_file_info* const file_info) {
+ fuse_file_info* const file_info) noexcept {
LOG(INFO) << "create(" << path << ")";
- if (std::strcmp(path, "/") == 0) {
- // They're asking to create the mount point. Huh?
- return -EEXIST;
- }
-
- std::unique_ptr<File> file;
-
try {
+ if (std::strcmp(path, "/") == 0) {
+ // They're asking to create the mount point. Huh?
+ return -EEXIST;
+ }
+
// Trim the leading slash so OpenAt will treat it relative to root_.
- file.reset(new File(root_->OpenAt(path + 1, file_info->flags, mode)));
+ std::unique_ptr<File> file(
+ new File(root_->OpenAt(path + 1, file_info->flags, mode)));
+
+ static_assert(sizeof(file_info->fh) == sizeof(std::uintptr_t),
+ "FUSE file handles are a different size than pointers");
+ file_info->fh = reinterpret_cast<std::uintptr_t>(file.release());
+ return 0;
} catch (const std::bad_alloc&) {
return -ENOMEM;
} catch (const std::system_error& e) {
return -e.code().value();
+ } catch (...) {
+ LOG(ERROR) << "create caught unexpected value";
+ return -ENOTRECOVERABLE;
}
-
- static_assert(sizeof(file_info->fh) == sizeof(std::uintptr_t),
- "FUSE file handles are a different size than pointers");
- file_info->fh = reinterpret_cast<std::uintptr_t>(file.release());
- return 0;
}
-int Release(const char*, fuse_file_info* const file_info) {
+int Release(const char*, fuse_file_info* const file_info) noexcept {
LOG(INFO) << "release";
File* const file = FileInfoFile(file_info);
delete file;
return 0;
}
-int Opendir(const char* const path, fuse_file_info* const file_info) {
+int Opendir(const char* const path, fuse_file_info* const file_info) noexcept {
LOG(INFO) << "opendir(" << path << ")";
- std::unique_ptr<Directory> directory;
-
try {
- directory.reset(new Directory(
- std::strcmp(path, "/") == 0
- ?
- // They're asking to open the mount point.
+ std::unique_ptr<Directory> directory(new Directory(
+ std::strcmp(path, "/") == 0 ?
+ // They're asking to open the mount point.
*root_
- :
- // Trim the leading slash so OpenAt will treat it relative to root_.
+ :
+ // Trim the leading slash so OpenAt will
+ // treat it relative to root_.
root_->OpenAt(path + 1, O_DIRECTORY)));
+ static_assert(sizeof(file_info->fh) == sizeof(std::uintptr_t),
+ "FUSE file handles are a different size than pointers");
+ file_info->fh = reinterpret_cast<std::uintptr_t>(directory.release());
+ return 0;
} catch (const std::bad_alloc&) {
return -ENOMEM;
} catch (const std::system_error& e) {
return -e.code().value();
+ } catch (...) {
+ LOG(ERROR) << "opendir caught unexpected value";
+ return -ENOTRECOVERABLE;
}
-
- static_assert(sizeof(file_info->fh) == sizeof(std::uintptr_t),
- "FUSE file handles are a different size than pointers");
- file_info->fh = reinterpret_cast<std::uintptr_t>(directory.release());
- return 0;
}
int Readdir(const char*, void* const buffer, fuse_fill_dir_t filler,
- const off_t offset, fuse_file_info* const file_info) {
+ const off_t offset, fuse_file_info* const file_info) noexcept {
LOG(INFO) << "readdir";
- Directory* const directory = FileInfoDirectory(file_info);
-
try {
+ Directory* const directory = FileInfoDirectory(file_info);
+
static_assert(std::is_same<off_t, long>(),
"off_t is not convertible with long");
if (offset != directory->offset()) {
@@ -195,16 +201,25 @@ int Readdir(const char*, void* const buffer, fuse_fill_dir_t filler,
}
} catch (const std::system_error& e) {
return -e.code().value();
+ } catch (...) {
+ LOG(ERROR) << "readdir caught unexpected value";
+ return -ENOTRECOVERABLE;
}
return 0;
}
-int Releasedir(const char*, fuse_file_info* const file_info) {
+int Releasedir(const char*, fuse_file_info* const file_info) noexcept {
LOG(INFO) << "releasedir";
- Directory* const directory = FileInfoDirectory(file_info);
- delete directory;
- return 0;
+
+ try {
+ Directory* const directory = FileInfoDirectory(file_info);
+ delete directory;
+ return 0;
+ } catch (...) {
+ LOG(ERROR) << "releasedir caught unexpected value";
+ return -ENOTRECOVERABLE;
+ }
}
} // namespace