system/FileDescriptor: new wrapper class for a file descriptor

src/fs/io/FileReader.cxx

@@ -75,17 +75,11 @@ FileReader::Close()
 
 #else
 
-#include <fcntl.h>
-#include <unistd.h>
-#include <errno.h>
-
 FileReader::FileReader(Path _path, Error &error)
-	:path(_path),
-	 fd(OpenFile(path,
-		     O_RDONLY,
-		     0))
+	:path(_path)
 {
-	if (fd < 0)
+	fd.OpenReadOnly(path.c_str());
+	if (!fd.IsDefined())
 		error.FormatErrno("Failed to open %s", path.c_str());
 }
 
@@ -94,7 +88,7 @@ FileReader::Read(void *data, size_t size, Error &error)
 {
 	assert(IsDefined());
 
-	ssize_t nbytes = read(fd, data, size);
+	ssize_t nbytes = fd.Read(data, size);
 	if (nbytes < 0) {
 		error.FormatErrno("Failed to read from %s", path.c_str());
 		nbytes = 0;
@@ -108,7 +102,7 @@ FileReader::Seek(off_t offset, Error &error)
 {
 	assert(IsDefined());
 
-	auto result = lseek(fd, offset, SEEK_SET);
+	auto result = fd.Seek(offset);
 	const bool success = result >= 0;
 	if (!success)
 		error.SetErrno("Failed to seek");
@@ -121,8 +115,7 @@ FileReader::Close()
 {
 	assert(IsDefined());
 
-	close(fd);
-	fd = -1;
+	fd.Close();
 }
 
 #endif

src/fs/io/FileReader.hxx

@@ -25,6 +25,10 @@
 #include "fs/AllocatedPath.hxx"
 #include "Compiler.h"
 
+#ifndef WIN32
+#include "system/FileDescriptor.hxx"
+#endif
+
 #include <assert.h>
 
 #ifdef WIN32
@@ -39,7 +43,7 @@ class FileReader final : public Reader {
 #ifdef WIN32
 	HANDLE handle;
 #else
-	int fd;
+	FileDescriptor fd;
 #endif
 
 public:
@@ -55,7 +59,7 @@ public:
 #ifdef WIN32
 		return handle != INVALID_HANDLE_VALUE;
 #else
-		return fd >= 0;
+		return fd.IsDefined();
 #endif
 	}