initial import of the C runtime

1 files changed, 73 insertions, 0 deletions

diff --git a/src/runtime/c/gu/file.c b/src/runtime/c/gu/file.c
new file mode 100644
index 000000000..ed1956537
--- /dev/null
+++ b/src/runtime/c/gu/file.c
@@ -0,0 +1,73 @@
+#include <gu/file.h>
+
+typedef struct GuFileOutStream GuFileOutStream;
+
+struct GuFileOutStream {
+	GuOutStream stream;
+	FILE* file;
+};
+
+static size_t
+gu_file_output(GuOutStream* stream, const uint8_t* buf, size_t len, GuExn* err)
+{
+	GuFileOutStream* fos = gu_container(stream, GuFileOutStream, stream);
+	errno = 0;
+	size_t wrote = fwrite(buf, 1, len, fos->file);
+	if (wrote < len) {
+		if (ferror(fos->file)) {
+			gu_raise_errno(err);
+		}
+	}
+	return wrote;
+}
+
+static void
+gu_file_flush(GuOutStream* stream, GuExn* err)
+{
+	GuFileOutStream* fos = gu_container(stream, GuFileOutStream, stream);
+	errno = 0;
+	if (fflush(fos->file) != 0) {
+		gu_raise_errno(err);
+	}
+}
+
+GuOut*
+gu_file_out(FILE* file, GuPool* pool)
+{
+	GuFileOutStream* fos = gu_new_i(pool, GuFileOutStream,
+					.stream.output = gu_file_output,
+					.stream.flush = gu_file_flush,
+					.file = file);
+	return gu_new_out(&fos->stream, pool);
+}
+
+
+typedef struct GuFileInStream GuFileInStream;
+
+struct GuFileInStream {
+	GuInStream stream;
+	FILE* file;
+};
+
+static size_t 
+gu_file_input(GuInStream* stream, uint8_t* buf, size_t sz, GuExn* err)
+{
+	GuFileInStream* fis = gu_container(stream, GuFileInStream, stream);
+	errno = 0;
+	size_t got = fread(buf, 1, sz, fis->file);
+	if (got == 0) {
+		if (ferror(fis->file)) {
+			gu_raise_errno(err);
+		}
+	}
+	return got;
+}
+
+GuIn*
+gu_file_in(FILE* file, GuPool* pool)
+{
+	GuFileInStream* fis = gu_new_s(pool, GuFileInStream,
+				       .stream.input = gu_file_input,
+				       .file = file);
+	return gu_new_in(&fis->stream, pool);
+}