From b5c9c8540a29babf990ff72b1eb5904424f1abb0 Mon Sep 17 00:00:00 2001
From: Benjamin Barenblat <bbaren@mit.edu>
Date: Sun, 21 Feb 2016 22:44:47 -0500
Subject: Implement ftruncate

---
 src/operations.cc   | 6 ++++++
 src/posix_extras.cc | 2 ++
 src/posix_extras.h  | 3 +++
 3 files changed, 11 insertions(+)

diff --git a/src/operations.cc b/src/operations.cc
index b1c568a..a82ad99 100644
--- a/src/operations.cc
+++ b/src/operations.cc
@@ -224,6 +224,11 @@ int Releasedir(const char*, fuse_file_info* const file_info) {
   return ReleaseResource<Directory>(file_info->fh);
 }
 
+int Ftruncate(const char*, const off_t size, fuse_file_info* const file_info) {
+  reinterpret_cast<File*>(file_info->fh)->Truncate(size);
+  return 0;
+}
+
 int Rmdir(const char* c_path) {
   const std::string path(c_path);
   if (path == "/") {
@@ -275,6 +280,7 @@ fuse_operations FuseOperations(File* const root) {
   result.write = CATCH_AND_RETURN_EXCEPTIONS(Write);
   result.utimens = CATCH_AND_RETURN_EXCEPTIONS(Utimens);
   result.release = CATCH_AND_RETURN_EXCEPTIONS(Release);
+  result.ftruncate = CATCH_AND_RETURN_EXCEPTIONS(Ftruncate);
   result.unlink = CATCH_AND_RETURN_EXCEPTIONS(Unlink);
 
   result.symlink = CATCH_AND_RETURN_EXCEPTIONS(Symlink);
diff --git a/src/posix_extras.cc b/src/posix_extras.cc
index 11db247..c0a5234 100644
--- a/src/posix_extras.cc
+++ b/src/posix_extras.cc
@@ -154,6 +154,8 @@ void File::SymLinkAt(const char* const target, const char* const source) const {
   CheckSyscall(symlinkat(target, fd_, source));
 }
 
+void File::Truncate(const off_t size) { CheckSyscall(ftruncate(fd_, size)); }
+
 void File::UnlinkAt(const char* const path) const {
   ValidatePath(path);
   CheckSyscall(unlinkat(fd_, path, 0));
diff --git a/src/posix_extras.h b/src/posix_extras.h
index 889175e..b67e2b4 100644
--- a/src/posix_extras.h
+++ b/src/posix_extras.h
@@ -112,6 +112,9 @@ class File {
   // indeed be relative (i.e., it must not start with '/').
   void SymLinkAt(const char* target, const char* source) const;
 
+  // Truncates the file to the specified size.
+  void Truncate(off_t);
+
   // Removes the file at the path relative to the file descriptor.  The path
   // must indeed be relative (i.e., it must not start with '/').
   void UnlinkAt(const char* path) const;
-- 
cgit v1.2.3