buffer: merge two buffer implementations

include/villas/buffer.hpp

-/** A simple growing buffer.
+/** A simple buffer for encoding streamed JSON messages.
  *
  * @file
  * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
@@ -23,29 +23,38 @@
 
 #pragma once
 
-#include <cstdlib>
 #include <vector>
 
-#include <jansson.h>
+#include <cstdlib>
 
-#include <villas/common.hpp>
+#include <jansson.h>
 
 namespace villas {
 
-class Buffer {
+class Buffer : public std::vector<char> {
 
-public:
-	std::vector<char> buf;
+protected:
+	static int callback(const char *data, size_t len, void *ctx);
 
-	Buffer(size_t size);
+public:
+	Buffer(const char *buf, size_type len) :
+		std::vector<char>(buf, buf+len)
+	{ }
 
-	void clear();
+	Buffer(size_type count = 0) :
+		std::vector<char>(count, 0)
+	{ }
 
-	int append(const char *data, size_t len);
+	/** Encode JSON document /p j and append it to the buffer */
+	int encode(json_t *j, int flags = 0);
 
-	int parseJson(json_t **j);
+	/** Decode JSON document from the beginning of the buffer */
+	json_t * decode();
 
-	int appendJson(json_t *j, int flags = 0);
+	void append(const char *data, size_t len)
+	{
+		insert(end(), data, data + len);
+	}
 };
 
 } /* namespace villas */

include/villas/json_buffer.hpp

-/** A simple buffer for encoding streamed JSON messages.
- *
- * @file
- * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
- * @copyright 2014-2020, Institute for Automation of Complex Power Systems, EONERC
- * @license GNU General Public License (version 3)
- *
- * VILLAScommon
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *********************************************************************************/
-
-#pragma once
-
-#include <vector>
-
-#include <cstdlib>
-
-#include <jansson.h>
-
-namespace villas {
-
-class JsonBuffer : public std::vector<char>
-{
-
-protected:
-	static int callback(const char *data, size_t len, void *ctx);
-
-public:
-	/** Encode JSON document /p j and append it to the buffer */
-	int encode(json_t *j, int flags = 0);
-
-	/** Decode JSON document from the beginning of the buffer */
-	json_t * decode();
-
-	void append(const char *data, size_t len)
-	{
-		insert(end(), data, data + len);
-	}
-};
-
-} /* namespace villas */

lib/CMakeLists.txt

@@ -23,7 +23,6 @@
 add_library(villas-common SHARED
 	advio.cpp
 	buffer.cpp
-	json_buffer.cpp
 	compat.cpp
 	hist.cpp
 	dsp/pid.cpp

lib/advio.cpp

@@ -245,7 +245,7 @@ AFILE * afopen(const char *uri, const char *mode)
 	/* Setup libcurl handle */
 	curl_easy_setopt(af->curl, CURLOPT_FOLLOWLOCATION, 1L);
 	curl_easy_setopt(af->curl, CURLOPT_UPLOAD, 0L);
-	curl_easy_setopt(af->curl, CURLOPT_USERAGENT, USER_AGENT);
+	curl_easy_setopt(af->curl, CURLOPT_USERAGENT, HTTP_USER_AGENT);
 	curl_easy_setopt(af->curl, CURLOPT_URL, af->uri);
 	curl_easy_setopt(af->curl, CURLOPT_WRITEDATA, af->file);
 	curl_easy_setopt(af->curl, CURLOPT_READDATA, af->file);

lib/buffer.cpp

-/** A simple growing buffer.
+/** A simple buffer for encoding streamed JSON messages.
  *
  * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
  * @copyright 2014-2020, Institute for Automation of Complex Power Systems, EONERC
@@ -20,49 +20,37 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *********************************************************************************/
 
-#include <cstring>
-
 #include <villas/compat.hpp>
 #include <villas/buffer.hpp>
-#include <villas/common.hpp>
-#include <villas/exceptions.hpp>
 
 using namespace villas;
 
-Buffer::Buffer(size_t sz) :
-	buf(sz, 0)
-{ }
-
-void Buffer::clear()
+json_t * Buffer::decode()
 {
-	buf.clear();
-}
+	json_t *j;
+	json_error_t err;
 
-int Buffer::append(const char *data, size_t l)
-{
-	buf.insert(buf.end(), data, data+l);
+	j = json_loadb(data(), size(), JSON_DISABLE_EOF_CHECK, &err);
+	if (!j)
+		return nullptr;
 
-	return 0;
+	/* Remove decoded JSON document from beginning */
+	erase(begin(), begin() + err.position);
+
+	return j;
 }
 
-int Buffer::parseJson(json_t **j)
+int Buffer::encode(json_t *j, int flags)
 {
-	*j = json_loadb(buf.data(), buf.size(), 0, nullptr);
-	if (!*j)
-		return -1;
-
-	return 0;
+	return json_dump_callback(j, callback, this, flags);
 }
 
-int Buffer::appendJson(json_t *j, int flags)
+int Buffer::callback(const char *data, size_t len, void *ctx)
 {
-	size_t l;
+	Buffer *b = static_cast<Buffer *>(ctx);
 
-retry:	l = json_dumpb(j, buf.data() + buf.size(), buf.capacity() - buf.size(), flags);
-	if (buf.capacity() < buf.size() + l) {
-		buf.reserve(buf.size() + l);
-		goto retry;
-	}
+	/* Append junk of JSON to buffer */
+	b->insert(b->end(), &data[0], &data[len]);
 
 	return 0;
 }

lib/json_buffer.cpp

-/** A simple buffer for encoding streamed JSON messages.
- *
- * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
- * @copyright 2014-2020, Institute for Automation of Complex Power Systems, EONERC
- * @license GNU General Public License (version 3)
- *
- * VILLAScommon
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *********************************************************************************/
-
-#include <villas/compat.hpp>
-#include <villas/json_buffer.hpp>
-
-using namespace villas;
-
-json_t * JsonBuffer::decode()
-{
-	json_t *j;
-	json_error_t err;
-
-	j = json_loadb(data(), size(), JSON_DISABLE_EOF_CHECK, &err);
-	if (!j)
-		return nullptr;
-
-	/* Remove decoded JSON document from beginning */
-	erase(begin(), begin() + err.position);
-
-	return j;
-}
-
-int JsonBuffer::encode(json_t *j, int flags)
-{
-	return json_dump_callback(j, callback, this, flags);
-}
-
-int JsonBuffer::callback(const char *data, size_t len, void *ctx)
-{
-	JsonBuffer *b = static_cast<JsonBuffer *>(ctx);
-
-	/* Append junk of JSON to buffer */
-	b->insert(b->end(), &data[0], &data[len]);
-
-	return 0;
-}

tests/unit/CMakeLists.txt

@@ -22,7 +22,7 @@
 
 add_executable(unit-tests-common
 	advio.cpp
-	json_buffer.cpp
+	buffer.cpp
 	graph.cpp
 	hist.cpp
 	kernel.cpp

tests/unit/json_buffer.cpp → tests/unit/buffer.cpp

@@ -26,18 +26,16 @@
 #include <criterion/criterion.h>
 #include <jansson.h>
 
-#include <villas/json_buffer.hpp>
+#include <villas/buffer.hpp>
 
 using namespace villas;
 
-using villas::JsonBuffer;
-
 // cppcheck-suppress unknownMacro
 TestSuite(buffer, .description = "Buffer datastructure");
 
-Test(json_buffer, decode)
+Test(buffer, decode)
 {
-	JsonBuffer buf;
+	Buffer buf;
 	json_t *j;
 	json_t *k;
 
@@ -54,10 +52,10 @@ Test(json_buffer, decode)
 	cr_assert(json_equal(j, k));
 }
 
-Test(json_buffer, encode)
+Test(buffer, encode)
 {
 	int ret;
-	JsonBuffer buf;
+	Buffer buf;
 	json_t *k;
 
 	const char *e = "{\"id\": \"5a786626-fbc6-4c04-98c2-48027e68c2fa\"}";
@@ -76,10 +74,10 @@ Test(json_buffer, encode)
 	json_decref(k);
 }
 
-Test(json_buffer, encode_decode)
+Test(buffer, encode_decode)
 {
 	int ret;
-	JsonBuffer buf;
+	Buffer buf;
 	json_t *k;
 	json_t *j;
 
@@ -100,12 +98,12 @@ Test(json_buffer, encode_decode)
 	json_decref(k);
 }
 
-Test(json_buffer, multiple)
+Test(buffer, multiple)
 {
 	int ret;
 	const int N = 100;
 
-	JsonBuffer buf;
+	Buffer buf;
 	json_t *k[N];
 	json_t *j[N];