cachelab started

cachelab/cbsl/src/write.c

@@ -0,0 +1,101 @@
+/*
+ * Copyright 2019 Yuta Hirokawa (University of Tsukuba, Japan)
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+
+#include "./cbsl_internal.h"
+
+static
+cbsl_errors streaming_write_flush(cbsl_ctx* ctx, uint64_t size)
+{
+	if (ctx->in_buffer_used > 0 && ctx->in_buffer_used + size > ctx->in_buffer_size)
+	{
+		CBSL_CHECK_COND_AND_RETURN(cbsl_flush(ctx) == cbsl_success, cbsl_error);
+	}
+	return cbsl_success;
+}
+
+static
+cbsl_errors streaming_write_immediate(cbsl_ctx* ctx, const void* data, uint64_t size)
+{
+	CBSL_DEBUG_MESSAGE("%s: call\n", __func__);
+	CBSL_CHECK_COND_AND_RETURN(streaming_write_flush(ctx, size) == cbsl_success, cbsl_error);
+
+	uint64_t written = 0;
+	const byte_t* pdata = (const byte_t*)(data);
+	while (written < size)
+	{
+		/* compressing data copies to internal input buffer */
+		const uint64_t write_size = MIN(size - written, ctx->in_buffer_size);
+		memcpy(ctx->in_buffer, pdata + written, write_size);
+		written += write_size;
+
+		ZSTD_inBuffer input = { ctx->in_buffer, write_size, 0 };
+		ZSTD_EndDirective mode = (size - written < ctx->in_buffer_size) ? ZSTD_e_end : ZSTD_e_continue;
+		do
+		{
+			ZSTD_outBuffer output = { ctx->out_buffer, ctx->out_buffer_size, 0 };
+			const size_t remaining = ZSTD_compressStream2(ctx->zstd_cctx, &output, &input, mode);
+			CBSL_CHECK_COND_MSG_AND_RETURN(!ZSTD_isError(remaining), ZSTD_getErrorName(remaining), cbsl_error);
+			CBSL_CHECK_COND_AND_RETURN(fwrite(ctx->out_buffer, 1, output.pos, ctx->fp) == output.pos, cbsl_error);
+		} while (input.pos < input.size);
+		CBSL_ASSERT(input.pos == input.size);
+	}
+	CBSL_ASSERT(written == size);
+
+	return cbsl_success;
+}
+
+static
+cbsl_errors streaming_write_buffered(cbsl_ctx* ctx, const void* data, uint64_t size)
+{
+	CBSL_DEBUG_MESSAGE("%s: call\n", __func__);
+	CBSL_CHECK_COND_AND_RETURN(streaming_write_flush(ctx, size) == cbsl_success, cbsl_error);
+
+	uint64_t written = 0;
+	const byte_t* pdata = (const byte_t*)(data);
+	do
+	{
+		const uint64_t write_size = MIN(size - written, ctx->in_buffer_size);
+		memcpy(ctx->in_buffer, pdata + written, write_size);
+		ctx->in_buffer_used = write_size;
+		CBSL_CHECK_COND_AND_RETURN(cbsl_flush(ctx) == cbsl_success, cbsl_error);
+		written += write_size;
+	} while (written < size);
+	CBSL_ASSERT(written == size);
+
+	return cbsl_success;
+}
+
+cbsl_errors cbsl_write(cbsl_ctx* ctx, const void* data, uint64_t size)
+{
+	CBSL_CHECK_COND_AND_RETURN(ctx != NULL, cbsl_error);
+	CBSL_CHECK_COND_AND_RETURN(ctx->mode == cbsl_store_mode, cbsl_error);
+	CBSL_CHECK_COND_AND_RETURN(data != NULL, cbsl_error);
+
+	CBSL_DEBUG_MESSAGE("write: %lu bytes\n", size);
+	if (size > ctx->in_buffer_size)
+	{
+		/* data size is larger than compression buffer */
+		return streaming_write_immediate(ctx, data, size);
+	}
+	else
+	{
+		return streaming_write_buffered(ctx, data, size);
+	}
+}