Add checked_{read,write} from DoM.

2 files changed, 33 insertions, 0 deletions

diff --git a/src/file.cc b/src/file.cc
index c80f5e58..8759c7c1 100644
--- a/src/file.cc
+++ b/src/file.cc
@@ -46,6 +46,7 @@ File::~File()
 
 
 File::File(boost::filesystem::path path, std::string mode)
+	: _path(path)
 {
 #ifdef LIBDCP_WINDOWS
 	std::wstring mode_wide(mode.begin(), mode.end());
@@ -105,6 +106,34 @@ File::operator bool() const
 }
 
 
+void
+File::checked_write(void const * ptr, size_t size)
+{
+	size_t N = write(ptr, 1, size);
+	if (N != size) {
+		if (ferror(_file)) {
+			throw FileError("fwrite error", _path, errno);
+		} else {
+			throw FileError("Unexpected short write", _path, 0);
+		}
+	}
+}
+
+
+void
+File::checked_read(void* ptr, size_t size)
+{
+	size_t N = read(ptr, 1, size);
+	if (N != size) {
+		if (ferror(_file)) {
+			throw FileError("fread error %1", _path, errno);
+		} else {
+			throw FileError("Unexpected short read", _path, 0);
+		}
+	}
+}
+
+
 /** Windows can't "by default" cope with paths longer than 260 characters, so if you pass such a path to
  *  any boost::filesystem method it will fail.  There is a "fix" for this, which is to prepend
  *  the string \\?\ to the path.  This will make it work, so long as:
diff --git a/src/file.h b/src/file.h
index 23204349..e0564cae 100644
--- a/src/file.h
+++ b/src/file.h
@@ -64,12 +64,16 @@ public:
 	/** fgets() wrapper */
 	char *gets(char *s, int size);
 
+	void checked_write(void const * ptr, size_t size);
+	void checked_read(void* ptr, size_t size);
+
 	/** Close the file; it is not necessary to call this as the
 	 *  destructor will do it if required.
 	 */
 	void close();
 
 private:
+	boost::filesystem::path _path;
 	FILE* _file = nullptr;
 };