VILLASnode/lib/formats/line.cpp

/** Line-based formats
 *
 * @author Steffen Vogel <post@steffenvogel.de>
 * @copyright 2014-2022, Institute for Automation of Complex Power Systems, EONERC
 * @license Apache 2.0
 *********************************************************************************/

#include <villas/formats/line.hpp>
#include <villas/exceptions.hpp>

using namespace villas;
using namespace villas::node;

int LineFormat::sprint(char *buf, size_t len, size_t *wbytes, const struct Sample * const smps[], unsigned cnt)
{
	unsigned i;
	size_t off = 0;

	for (i = 0; i < cnt && off < len; i++)
		off += sprintLine(buf + off, len - off, smps[i]);

	if (wbytes)
		*wbytes = off;

	return i;
}

int LineFormat::sscan(const char *buf, size_t len, size_t *rbytes, struct Sample * const smps[], unsigned cnt)
{
	unsigned i;
	size_t off = 0;

	if (skip_first_line) {
		if (!first_line_skipped) {
			while (off < len) {
				if (buf[off++] == delimiter)
					break;
			}

			first_line_skipped = true;
		}
	}

	for (i = 0; i < cnt && off < len; i++) {
		/* Skip comment lines */
		if (buf[off] == comment) {
			while (off < len) {
				if (buf[++off] == delimiter)
					break;
			}

			if (off == len)
				break;
		}

		off += sscanLine(buf + off, len - off, smps[i]);
	}

	if (rbytes)
		*rbytes = off;

	return i;
}

int LineFormat::print(FILE *f, const struct Sample * const smps[], unsigned cnt)
{
	int ret;
	unsigned i;

	if (cnt > 0 && smps[0]->signals)
		header(f, smps[0]->signals);

	for (i = 0; i < cnt; i++) {
		size_t wbytes;

		ret = sprint(out.buffer, out.buflen, &wbytes, &smps[i], 1);
		if (ret < 0)
			return ret;

		fwrite(out.buffer, wbytes, 1, f);
	}

	return i;
}

int LineFormat::scan(FILE *f, struct Sample * const smps[], unsigned cnt)
{
	int ret;
	unsigned i;
	ssize_t bytes;

	if (skip_first_line) {
		if (!first_line_skipped) {
			bytes = getdelim(&in.buffer, &in.buflen, delimiter, f);
			if (bytes < 0)
				return -1; /* An error or eof occured */

			first_line_skipped = true;
		}
	}

	for (i = 0; i < cnt && !feof(f); i++) {
		size_t rbytes;
		char *ptr;

skip:		bytes = getdelim(&in.buffer, &in.buflen, delimiter, f);
		if (feof(f))
			break;
		else if (bytes < 0)
			return -1; /* An error or eof occured */

		/* Skip whitespaces, empty and comment lines */
		for (ptr = in.buffer; isspace(*ptr); ptr++);

		if (ptr[0] == '\0' || ptr[0] == comment)
			goto skip;

		ret = sscan(in.buffer, bytes, &rbytes, &smps[i], 1);
		if (ret < 0)
			return ret;
	}

	return i;
}

void LineFormat::parse(json_t *json)
{
	int ret;
	json_error_t err;
	const char *delim = nullptr;
	const char *com = nullptr;
	int header = -1;
	int skip = -1;

	ret = json_unpack_ex(json, &err, 0, "{ s?: s, s?: b, s?: b, s?: s }",
		"delimiter", &delim,
		"header", &header,
		"skip_first_line", &skip,
		"comment_prefix", &com
	);
	if (ret)
		throw ConfigError(json, err, "node-config-format-line", "Failed to parse format configuration");

	if (delim) {
		if (strlen(delim) != 1)
			throw ConfigError(json, "node-config-format-line-delimiter", "Line delimiter must be a single character!");

		delimiter = delim[0];
	}

	if (com) {
		if (strlen(com) != 1)
			throw ConfigError(json, "node-config-format-line-comment_prefix", "Comment prefix must be a single character!");

		comment = com[0];
	}

	if (header >= 0)
		print_header = header;

	if (skip >= 0)
		skip_first_line = skip;

	Format::parse(json);
}