ircd::fs: Refactor fs::write stack for fs::fd.

include/ircd/fs/write.h

@@ -16,6 +16,7 @@ namespace ircd::fs
 	struct write_opts extern const write_opts_default;
 
 	// Yields ircd::ctx for write from buffer; returns view of written portion
+	const_buffer write(const fd &, const const_buffer &, const write_opts & = write_opts_default);
 	const_buffer write(const string_view &path, const const_buffer &, const write_opts & = write_opts_default);
 
 	// Yields ircd::ctx to overwrite (trunc) file from buffer; returns view of written portion
@@ -31,15 +32,6 @@ struct ircd::fs::write_opts
 	write_opts() = default;
 	write_opts(const off_t &);
 
-	/// Overwrite (trunc) the file
-	bool overwrite {false};
-
-	/// Append to the file (offset is ignored)
-	bool append {false};
-
-	/// Create the file if necessary (default)
-	bool create {true};
-
 	/// Offset in the file to start the write from.
 	off_t offset {0};
 
@@ -55,19 +47,25 @@ ircd::fs::write_opts::write_opts(const off_t &offset)
 inline ircd::const_buffer
 ircd::fs::overwrite(const string_view &path,
                     const const_buffer &buf,
-                    const write_opts &opts_)
+                    const write_opts &opts)
 {
-	auto opts(opts_);
-	opts.overwrite = true;
-	return write(path, buf, opts);
+	const fd fd
+	{
+		path, std::ios::out | std::ios::trunc
+	};
+
+	return write(fd, buf, opts);
 }
 
 inline ircd::const_buffer
 ircd::fs::append(const string_view &path,
                  const const_buffer &buf,
-                 const write_opts &opts_)
+                 const write_opts &opts)
 {
-	auto opts(opts_);
-	opts.append = true;
-	return write(path, buf, opts);
+	const fd fd
+	{
+		path, std::ios::out | std::ios::app
+	};
+
+	return write(fd, buf, opts);
 }

ircd/aio.cc

@@ -343,39 +343,13 @@ ircd::fs::aio::request::write::write(const int &fd,
 //
 
 ircd::const_buffer
-ircd::fs::write__aio(const string_view &path,
+ircd::fs::write__aio(const fd &fd,
                      const const_buffer &buf,
                      const write_opts &opts)
 {
-	// Path to open(2) must be null terminated;
-	static thread_local char pathstr[2048];
-	strlcpy(pathstr, path, sizeof(pathstr));
-
-	uint flags{0};
-	flags |= O_WRONLY;
-	flags |= O_CLOEXEC;
-	flags |= opts.create? O_CREAT : 0;
-	flags |= opts.append? O_APPEND : 0;
-	flags |= opts.overwrite? O_TRUNC : 0;
-
-	const mode_t mask
-	{
-		opts.create? S_IRUSR | S_IWUSR : 0U
-	};
-
-	const auto fd
-	{
-		syscall(::open, pathstr, flags, mask)
-	};
-
-	const unwind cfd{[&fd]
-	{
-		syscall(::close, fd);
-	}};
-
 	aio::request::write request
 	{
-		int(fd), buf, opts
+		fd, buf, opts
 	};
 
 	const size_t bytes

ircd/aio.h

@@ -74,7 +74,7 @@ struct ircd::fs::aio::request
 
 namespace ircd::fs
 {
-	const_buffer write__aio(const string_view &path, const const_buffer &, const write_opts &);
+	const_buffer write__aio(const fd &, const const_buffer &, const write_opts &);
 	const_buffer read__aio(const fd &, const mutable_buffer &, const read_opts &);
 }
 

ircd/fs.cc

@@ -216,11 +216,6 @@ catch(const std::exception &e)
 // fs/write.h
 //
 
-namespace ircd::fs
-{
-	const_buffer write__std(const string_view &path, const const_buffer &, const write_opts &);
-}
-
 ircd::fs::write_opts
 const ircd::fs::write_opts_default
 {};
@@ -231,12 +226,16 @@ ircd::fs::write(const string_view &path,
                 const write_opts &opts)
 try
 {
-	#ifdef IRCD_USE_AIO
-	if(likely(aioctx))
-		return write__aio(path, buf, opts);
-	#endif
+	const fd fd
+	{
+		path, std::ios::out
+	};
 
-	return write__std(path, buf, opts);
+	return write(fd, buf, opts);
+}
+catch(const filesystem_error &)
+{
+	throw;
 }
 catch(const std::exception &e)
 {
@@ -247,29 +246,32 @@ catch(const std::exception &e)
 }
 
 ircd::const_buffer
-ircd::fs::write__std(const string_view &path,
-                     const const_buffer &buf,
-                     const write_opts &opts)
+ircd::fs::write(const fd &fd,
+                const const_buffer &buf,
+                const write_opts &opts)
+try
 {
-	const auto open_mode
+	#ifdef IRCD_USE_AIO
+	if(likely(aioctx))
+		return write__aio(fd, buf, opts);
+	#endif
+
+	return
 	{
-		opts.append?
-			std::ios::app:
-
-		opts.overwrite?
-			std::ios::trunc:
-
-		std::ios::out
+		data(buf),
+		size_t(syscall(::pwrite, fd, data(buf), size(buf), opts.offset))
 	};
-
-	std::ofstream file
+}
+catch(const filesystem_error &)
+{
+	throw;
+}
+catch(const std::exception &e)
+{
+	throw filesystem_error
 	{
-		std::string{path}, open_mode
+		"%s", e.what()
 	};
-
-	file.seekp(opts.offset, file.beg);
-	file.write(data(buf), size(buf));
-	return buf;
 }
 
 ///////////////////////////////////////////////////////////////////////////////