added new internal data structure for samples (instead of the old struct msg)

include/sample.h

@@ -0,0 +1,95 @@
+/** The internal datastructure for a sample of simulation data.
+ *
+ * @file
+ * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
+ * @copyright 2014-2016, Institute for Automation of Complex Power Systems, EONERC
+ *   This file is part of S2SS. All Rights Reserved. Proprietary and confidential.
+ *   Unauthorized copying of this file, via any medium is strictly prohibited. 
+ */
+
+#ifndef _SAMPLE_H_
+#define _SAMPLE_H_
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <time.h>
+#include <sys/types.h>
+
+/** The length of a sample datastructure with \p values values in bytes. */
+#define SAMPLE_LEN(values)	(sizeof(struct sample) + SAMPLE_DATA_LEN(values))
+
+/** The length of a sample data portion of a sample datastructure with \p values values in bytes. */
+#define SAMPLE_DATA_LEN(values)	((values) * sizeof(float))
+
+/** The offset to the beginning of the data section. */
+#define SAMPLE_DATA_OFFSET(smp)	((char *) (smp) + offsetof(struct sample, values))
+
+/** These flags define the format which is used by sample_fscan() and sample_fprint(). */
+enum sample_flags {
+	SAMPLE_NANOSECONDS	= 1,
+	SAMPLE_OFFSET		= 2,
+	SAMPLE_SEQUENCE		= 4,
+	SAMPLE_VALUES		= 8,
+	SAMPLE_ALL		= 16-1
+};
+
+struct sample {
+	int length;		/**< The number of values in sample::values. */
+	int sequence;		/**< The sequence number of this sample. */
+
+	/** All timestamps are seconds / nano seconds after 1.1.1970 UTC */
+	struct {
+		struct timespec origin;		/**< The point in time when this data was sampled. */
+		struct timespec received;	/**< The point in time when this data was received. */
+		struct timespec sent;		/**< The point in time this data was send for the last time. */
+	} ts;
+	
+	/** The values. */
+	union {
+		float    f;	/**< Floating point values (note msg::endian) */
+		uint32_t i;	/**< Integer values (note msg::endian) */
+	} values[];
+};
+
+/** Print a sample in human readable form to a file stream.
+ *
+ * @param buf A character buffer of len bytes.
+ * @param len The size of buf.
+ * @param m A pointer to the sample.
+ * @param flags See sample_flags.
+ * @return Number of bytes written to buf.
+ */
+int sample_print(char *buf, size_t len, struct sample *s, int flags);
+
+/** Read a sample from a character buffer.
+ *
+ * @param line A string which should be parsed.
+ * @param s A pointer to the sample.
+ * @param flags et SAMPLE_* flags for each component found in sample if not NULL. See sample_flags.
+ * @retval 0 Success. Everything went well.
+ * @retval <0 Error. Something went wrong.
+ */
+int sample_scan(const char *line, struct sample *s, int *fl);
+
+/** Print a sample in human readable form to a file stream.
+ *
+ * @see sample_print()
+ * @param f The file handle from fopen() or stdout, stderr.
+ * @param s A pointer to the sample.
+ * @retval 0 Success. Everything went well.
+ * @retval <0 Error. Something went wrong.
+ */
+int sample_fprint(FILE *f, struct sample *s, int flags);
+
+/** Read a sample from a file stream.
+ *
+ * @see sample_scan()
+ * @param f The file handle from fopen() or stdin.
+ * @param s A pointer to the sample.
+ * @retval 0 Success. Everything went well.
+ * @retval <0 Error. Something went wrong.
+ */
+int sample_fscan(FILE *f, struct sample *s, int *flags);
+
+#endif /* _SAMPLE_H_ */

lib/sample.c

@@ -0,0 +1,141 @@
+/** The internal datastructure for a sample of simulation data.
+ *
+ * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
+ * @copyright 2014-2016, Institute for Automation of Complex Power Systems, EONERC
+ *   This file is part of S2SS. All Rights Reserved. Proprietary and confidential.
+ *   Unauthorized copying of this file, via any medium is strictly prohibited.
+ *********************************************************************************/
+
+#include <ctype.h>
+
+#include "sample.h"
+#include "timing.h"
+
+int sample_print(char *buf, size_t len, struct sample *s, int flags)
+{
+	size_t off = snprintf(buf, len, "%llu", (unsigned long long) s->ts.origin.tv_sec);
+	
+	if (flags & SAMPLE_NANOSECONDS)
+		off += snprintf(buf + off, len - off, ".%09llu", (unsigned long long) s->ts.origin.tv_nsec);
+	
+	if (flags & SAMPLE_OFFSET)
+		off += snprintf(buf + off, len - off, "%+g", time_delta(&s->ts.received, &s->ts.origin));
+	
+	if (flags & SAMPLE_SEQUENCE)
+		off += snprintf(buf + off, len - off, "(%u)", s->sequence);
+
+	if (flags & SAMPLE_VALUES) {
+		for (int i = 0; i < s->length; i++)
+			off += snprintf(buf + off, len - off, "\t%.6f", s->values[i].f);
+	}
+
+	off += snprintf(buf + off, len - off, "\n");
+
+	return off + 1; /* trailing '\0' */
+}
+
+int sample_scan(const char *line, struct sample *s, int *fl)
+{
+	char *end;
+	const char *ptr = line;
+
+	int flags = 0;
+	double offset = 0;
+
+	/* Format: Seconds.NanoSeconds+Offset(SequenceNumber) Value1 Value2 ... 
+	 * RegEx: (\d+(?:\.\d+)?)([-+]\d+(?:\.\d+)?(?:e[+-]?\d+)?)?(?:\((\d+)\))?
+	 *
+	 * Please note that only the seconds and at least one value are mandatory
+	 */
+
+	/* Mandatory: seconds */
+	s->ts.origin.tv_sec = (uint32_t) strtoul(ptr, &end, 10);
+	if (ptr == end)
+		return -2;
+
+	/* Optional: nano seconds */
+	if (*end == '.') {
+		ptr = end + 1;
+
+		s->ts.origin.tv_nsec = (uint32_t) strtoul(ptr, &end, 10);
+		if (ptr != end)
+			flags |= SAMPLE_NANOSECONDS;
+		else
+			return -3;
+	}
+	else
+		s->ts.origin.tv_nsec = 0;
+
+	/* Optional: offset / delay */
+	if (*end == '+' || *end == '-') {
+		ptr = end;
+
+		offset = strtof(ptr, &end); /* offset is ignored for now */
+		if (ptr != end)
+			flags |= SAMPLE_OFFSET;
+		else
+			return -4;
+	}
+	
+	/* Optional: sequence */
+	if (*end == '(') {
+		ptr = end + 1;
+		
+		s->sequence = strtoul(ptr, &end, 10);
+		if (ptr != end)
+			flags |= SAMPLE_SEQUENCE;
+		else
+			return -5;
+		
+		if (*end == ')')
+			end++;
+	}
+
+	for (s->length = 0, ptr  = end; ;
+	     s->length++,   ptr = end) {
+
+		/** @todo We only support floating point values at the moment */
+		s->values[s->length].f = strtod(ptr, &end);
+
+		if (end == ptr) /* there are no valid FP values anymore */
+			break;
+	}
+	
+	if (s->length > 0)
+		flags |= SAMPLE_VALUES;
+	
+	if (fl)
+		*fl = flags;
+	if (flags & SAMPLE_OFFSET) {
+		struct timespec off = time_from_double(offset);
+		s->ts.received = time_diff(&s->ts.origin, &off);
+	}
+
+	return s->length;
+}
+
+int sample_fprint(FILE *f, struct sample *s, int flags)
+{
+	char line[4096];
+
+	int len = sample_print(line, sizeof(line), s, flags);
+	
+	fputs(line, f);
+	
+	return len;
+}
+
+int sample_fscan(FILE *f, struct sample *s, int *fl)
+{
+	char *ptr, line[4096];
+	
+skip:	if (fgets(line, sizeof(line), f) == NULL)
+		return -1; /* An error occured */
+
+	/* Skip whitespaces, empty and comment lines */
+	for (ptr = line; isspace(*ptr); ptr++);
+	if (*ptr == '\0' || *ptr == '#')
+		goto skip;
+	
+	return sample_scan(line, s, fl);
+}