Move all core-functionality to subsurface-core

And adapt a new CMakeLists.txt file for it. On the way I've also
found out that we where double-compilling a few files. I've also
set the subsurface-core as a include_path but that was just to
reduce the noise on this commit, since I plan to remove it from
the include path to make it obligatory to specify something like

 include "subsurface-core/dive.h"

for the header files. Since the app is growing quite a bit we ended
up having a few different files with almost same name that did
similar things, I want to kill that (for instance Dive.h, dive.h,
PrintDive.h and such).

Signed-off-by: Tomaz Canabrava <tomaz.canabrava@intel.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 435 insertions, 0 deletions

diff --git a/subsurface-core/gaspressures.c b/subsurface-core/gaspressures.c
new file mode 100644
index 000000000..5f46d6080
--- /dev/null
+++ b/subsurface-core/gaspressures.c
@@ -0,0 +1,435 @@
+/*  gaspressures.c
+ *  ---------------
+ *  This file contains the routines to calculate the gas pressures in the cylinders.
+ *  The functions below support the code in profile.c.
+ *  The high-level function is populate_pressure_information(), called by function
+ *  create_plot_info_new() in profile.c. The other functions below are, in turn,
+ *  called by populate_pressure_information(). The calling sequence is as follows:
+ *
+ *  populate_pressure_information() -> calc_pressure_time()
+ *                                  -> fill_missing_tank_pressures() -> fill_missing_segment_pressures()
+ *                                                                   -> get_pr_interpolate_data()
+ *
+ *  The pr_track_t related functions below implement a linked list that is used by
+ *  the majority of the functions below. The linked list covers a part of the dive profile
+ *  for which there are no cylinder pressure data. Each element in the linked list
+ *  represents a segment between two consecutive points on the dive profile.
+ *  pr_track_t is defined in gaspressures.h
+ */
+
+#include "dive.h"
+#include "display.h"
+#include "profile.h"
+#include "gaspressures.h"
+
+static pr_track_t *pr_track_alloc(int start, int t_start)
+{
+	pr_track_t *pt = malloc(sizeof(pr_track_t));
+	pt->start = start;
+	pt->end = 0;
+	pt->t_start = pt->t_end = t_start;
+	pt->pressure_time = 0;
+	pt->next = NULL;
+	return pt;
+}
+
+/* poor man's linked list */
+static pr_track_t *list_last(pr_track_t *list)
+{
+	pr_track_t *tail = list;
+	if (!tail)
+		return NULL;
+	while (tail->next) {
+		tail = tail->next;
+	}
+	return tail;
+}
+
+static pr_track_t *list_add(pr_track_t *list, pr_track_t *element)
+{
+	pr_track_t *tail = list_last(list);
+	if (!tail)
+		return element;
+	tail->next = element;
+	return list;
+}
+
+static void list_free(pr_track_t *list)
+{
+	if (!list)
+		return;
+	list_free(list->next);
+	free(list);
+}
+
+#ifdef DEBUG_PR_TRACK
+static void dump_pr_track(pr_track_t **track_pr)
+{
+	int cyl;
+	pr_track_t *list;
+
+	for (cyl = 0; cyl < MAX_CYLINDERS; cyl++) {
+		list = track_pr[cyl];
+		while (list) {
+			printf("cyl%d: start %d end %d t_start %d t_end %d pt %d\n", cyl,
+			       list->start, list->end, list->t_start, list->t_end, list->pressure_time);
+			list = list->next;
+		}
+	}
+}
+#endif
+
+/*
+ * This looks at the pressures for one cylinder, and
+ * calculates any missing beginning/end pressures for
+ * each segment by taking the over-all SAC-rate into
+ * account for that cylinder.
+ *
+ * NOTE! Many segments have full pressure information
+ * (both beginning and ending pressure). But if we have
+ * switched away from a cylinder, we will have the
+ * beginning pressure for the first segment with a
+ * missing end pressure. We may then have one or more
+ * segments without beginning or end pressures, until
+ * we finally have a segment with an end pressure.
+ *
+ * We want to spread out the pressure over these missing
+ * segments according to how big of a time_pressure area
+ * they have.
+ */
+static void fill_missing_segment_pressures(pr_track_t *list, enum interpolation_strategy strategy)
+{
+	double magic;
+
+	while (list) {
+		int start = list->start, end;
+		pr_track_t *tmp = list;
+		int pt_sum = 0, pt = 0;
+
+		for (;;) {
+			pt_sum += tmp->pressure_time;
+			end = tmp->end;
+			if (end)
+				break;
+			end = start;
+			if (!tmp->next)
+				break;
+			tmp = tmp->next;
+		}
+
+		if (!start)
+			start = end;
+
+		/*
+		 * Now 'start' and 'end' contain the pressure values
+		 * for the set of segments described by 'list'..'tmp'.
+		 * pt_sum is the sum of all the pressure-times of the
+		 * segments.
+		 *
+		 * Now dole out the pressures relative to pressure-time.
+		 */
+		list->start = start;
+		tmp->end = end;
+		switch (strategy) {
+		case SAC:
+			for (;;) {
+				int pressure;
+				pt += list->pressure_time;
+				pressure = start;
+				if (pt_sum)
+					pressure -= (start - end) * (double)pt / pt_sum;
+				list->end = pressure;
+				if (list == tmp)
+					break;
+				list = list->next;
+				list->start = pressure;
+			}
+			break;
+		case TIME:
+			if (list->t_end && (tmp->t_start - tmp->t_end)) {
+				magic = (list->t_start - tmp->t_end) / (tmp->t_start - tmp->t_end);
+				list->end = rint(start - (start - end) * magic);
+			} else {
+				list->end = start;
+			}
+			break;
+		case CONSTANT:
+			list->end = start;
+		}
+
+		/* Ok, we've done that set of segments */
+		list = list->next;
+	}
+}
+
+#ifdef DEBUG_PR_INTERPOLATE
+void dump_pr_interpolate(int i, pr_interpolate_t interpolate_pr)
+{
+	printf("Interpolate for entry %d: start %d - end %d - pt %d - acc_pt %d\n", i,
+	       interpolate_pr.start, interpolate_pr.end, interpolate_pr.pressure_time, interpolate_pr.acc_pressure_time);
+}
+#endif
+
+
+static struct pr_interpolate_struct get_pr_interpolate_data(pr_track_t *segment, struct plot_info *pi, int cur, int pressure)
+{ // cur = index to pi->entry corresponding to t_end of segment;
+	struct pr_interpolate_struct interpolate;
+	int i;
+	struct plot_data *entry;
+
+	interpolate.start = segment->start;
+	interpolate.end = segment->end;
+	interpolate.acc_pressure_time = 0;
+	interpolate.pressure_time = 0;
+
+	for (i = 0; i < pi->nr; i++) {
+		entry = pi->entry + i;
+
+		if (entry->sec < segment->t_start)
+			continue;
+		if (entry->sec >= segment->t_end) {
+			interpolate.pressure_time += entry->pressure_time;
+			break;
+		}
+		if (entry->sec == segment->t_start) {
+			interpolate.acc_pressure_time = 0;
+			interpolate.pressure_time = 0;
+			if (pressure)
+				interpolate.start = pressure;
+			continue;
+		}
+		if (i < cur) {
+			if (pressure) {
+				interpolate.start = pressure;
+				interpolate.acc_pressure_time = 0;
+				interpolate.pressure_time = 0;
+			} else {
+				interpolate.acc_pressure_time += entry->pressure_time;
+				interpolate.pressure_time += entry->pressure_time;
+			}
+			continue;
+		}
+		if (i == cur) {
+			interpolate.acc_pressure_time += entry->pressure_time;
+			interpolate.pressure_time += entry->pressure_time;
+			continue;
+		}
+		interpolate.pressure_time += entry->pressure_time;
+		if (pressure) {
+			interpolate.end = pressure;
+			break;
+		}
+	}
+	return interpolate;
+}
+
+static void fill_missing_tank_pressures(struct dive *dive, struct plot_info *pi, pr_track_t **track_pr, bool o2_flag)
+{
+	int cyl, i;
+	struct plot_data *entry;
+	int cur_pr[MAX_CYLINDERS]; // cur_pr[MAX_CYLINDERS] is the CCR diluent cylinder
+
+	for (cyl = 0; cyl < MAX_CYLINDERS; cyl++) {
+		enum interpolation_strategy strategy;
+		if (!track_pr[cyl]) {
+			/* no segment where this cylinder is used */
+			cur_pr[cyl] = -1;
+			continue;
+		}
+		if (dive->cylinder[cyl].cylinder_use == OC_GAS)
+			strategy = SAC;
+		else
+			strategy = TIME;
+		fill_missing_segment_pressures(track_pr[cyl], strategy); // Interpolate the missing tank pressure values ..
+		cur_pr[cyl] = track_pr[cyl]->start;	       // in the pr_track_t lists of structures
+	}						       // and keep the starting pressure for each cylinder.
+
+#ifdef DEBUG_PR_TRACK
+	/* another great debugging tool */
+	dump_pr_track(track_pr);
+#endif
+
+	/* Transfer interpolated cylinder pressures from pr_track strucktures to plotdata
+	 * Go down the list of tank pressures in plot_info. Align them with the start &
+	 * end times of each profile segment represented by a pr_track_t structure. Get
+	 * the accumulated pressure_depths from the pr_track_t structures and then
+	 * interpolate the pressure where these do not exist in the plot_info pressure
+	 * variables. Pressure values are transferred from the pr_track_t structures
+	 * to the plot_info structure, allowing us to plot the tank pressure.
+	 *
+	 * The first two pi structures are "fillers", but in case we don't have a sample
+	 * at time 0 we need to process the second of them here, therefore i=1 */
+	for (i = 1; i < pi->nr; i++) { // For each point on the profile:
+		double magic;
+		pr_track_t *segment;
+		pr_interpolate_t interpolate;
+		int pressure;
+		int *save_pressure, *save_interpolated;
+
+		entry = pi->entry + i;
+
+		if (o2_flag) {
+			// Find the cylinder index (cyl) and pressure
+			cyl = dive->oxygen_cylinder_index;
+			if (cyl < 0)
+				return;   // Can we do this?!?
+			pressure = O2CYLINDER_PRESSURE(entry);
+			save_pressure = &(entry->o2cylinderpressure[SENSOR_PR]);
+			save_interpolated = &(entry->o2cylinderpressure[INTERPOLATED_PR]);
+		} else {
+			pressure = SENSOR_PRESSURE(entry);
+			save_pressure = &(entry->pressure[SENSOR_PR]);
+			save_interpolated = &(entry->pressure[INTERPOLATED_PR]);
+			cyl = entry->cylinderindex;
+		}
+
+		if (pressure) {			// If there is a valid pressure value,
+			cur_pr[cyl] = pressure; // set current pressure
+			continue;		// and skip to next point.
+		}
+		// If there is NO valid pressure value..
+		// Find the pressure segment corresponding to this entry..
+		segment = track_pr[cyl];
+		while (segment && segment->t_end < entry->sec) // Find the track_pr with end time..
+			segment = segment->next;	       // ..that matches the plot_info time (entry->sec)
+
+		if (!segment || !segment->pressure_time) { // No (or empty) segment?
+			*save_pressure = cur_pr[cyl];      // Just use our current pressure
+			continue;			   // and skip to next point.
+		}
+
+		// If there is a valid segment but no tank pressure ..
+		interpolate = get_pr_interpolate_data(segment, pi, i, pressure); // Set up an interpolation structure
+		if(dive->cylinder[cyl].cylinder_use == OC_GAS) {
+
+			/* if this segment has pressure_time, then calculate a new interpolated pressure */
+			if (interpolate.pressure_time) {
+				/* Overall pressure change over total pressure-time for this segment*/
+				magic = (interpolate.end - interpolate.start) / (double)interpolate.pressure_time;
+
+				/* Use that overall pressure change to update the current pressure */
+				cur_pr[cyl] = rint(interpolate.start + magic * interpolate.acc_pressure_time);
+			}
+		} else {
+			magic = (interpolate.end - interpolate.start) /  (segment->t_end - segment->t_start);
+			cur_pr[cyl] = rint(segment->start + magic * (entry->sec - segment->t_start));
+		}
+		*save_interpolated = cur_pr[cyl]; // and store the interpolated data in plot_info
+	}
+}
+
+
+/*
+ * What's the pressure-time between two plot data entries?
+ * We're calculating the integral of pressure over time by
+ * adding these up.
+ *
+ * The units won't matter as long as everybody agrees about
+ * them, since they'll cancel out - we use this to calculate
+ * a constant SAC-rate-equivalent, but we only use it to
+ * scale pressures, so it ends up being a unitless scaling
+ * factor.
+ */
+static inline int calc_pressure_time(struct dive *dive, struct divecomputer *dc, struct plot_data *a, struct plot_data *b)
+{
+	int time = b->sec - a->sec;
+	int depth = (a->depth + b->depth) / 2;
+
+	if (depth <= SURFACE_THRESHOLD)
+		return 0;
+
+	return depth_to_mbar(depth, dive) * time;
+}
+
+#ifdef PRINT_PRESSURES_DEBUG
+// A CCR debugging tool that prints the gas pressures in cylinder 0 and in the diluent cylinder, used in populate_pressure_information():
+static void debug_print_pressures(struct plot_info *pi)
+{
+	int i;
+	for (i = 0; i < pi->nr; i++) {
+		struct plot_data *entry = pi->entry + i;
+		printf("%5d |%9d | %9d || %9d | %9d |\n", i, SENSOR_PRESSURE(entry), INTERPOLATED_PRESSURE(entry), DILUENT_PRESSURE(entry), INTERPOLATED_DILUENT_PRESSURE(entry));
+	}
+}
+#endif
+
+/* This function goes through the list of tank pressures, either SENSOR_PRESSURE(entry) or O2CYLINDER_PRESSURE(entry),
+ * of structure plot_info for the dive profile where each item in the list corresponds to one point (node) of the
+ * profile. It finds values for which there are no tank pressures (pressure==0). For each missing item (node) of
+ * tank pressure it creates a pr_track_alloc structure that represents a segment on the dive profile and that
+ * contains tank pressures. There is a linked list of pr_track_alloc structures for each cylinder. These pr_track_alloc
+ * structures ultimately allow for filling the missing tank pressure values on the dive profile using the depth_pressure
+ * of the dive. To do this, it calculates the summed pressure-time value for the duration of the dive and stores these
+ * in the pr_track_alloc structures. If diluent_flag = 1, then DILUENT_PRESSURE(entry) is used instead of SENSOR_PRESSURE.
+ * This function is called by create_plot_info_new() in profile.c
+ */
+void populate_pressure_information(struct dive *dive, struct divecomputer *dc, struct plot_info *pi, int o2_flag)
+{
+	int i, cylinderid, cylinderindex = -1;
+	pr_track_t *track_pr[MAX_CYLINDERS] = { NULL, };
+	pr_track_t *current = NULL;
+	bool missing_pr = false;
+
+	for (i = 0; i < pi->nr; i++) {
+		struct plot_data *entry = pi->entry + i;
+		unsigned pressure;
+		if (o2_flag) { // if this is a diluent cylinder:
+			pressure = O2CYLINDER_PRESSURE(entry);
+			cylinderid = dive->oxygen_cylinder_index;
+			if (cylinderid < 0)
+				goto GIVE_UP;
+		} else {
+			pressure = SENSOR_PRESSURE(entry);
+			cylinderid = entry->cylinderindex;
+		}
+		/* If track_pr structure already exists, then update it: */
+		/* discrete integration of pressure over time to get the SAC rate equivalent */
+		if (current) {
+			entry->pressure_time = calc_pressure_time(dive, dc, entry - 1, entry);
+			current->pressure_time += entry->pressure_time;
+			current->t_end = entry->sec;
+		}
+
+		/* If 1st record or different cylinder: Create a new track_pr structure: */
+		/* track the segments per cylinder and their pressure/time integral */
+		if (cylinderid != cylinderindex) {
+			if (o2_flag)			  // For CCR dives:
+				cylinderindex = dive->oxygen_cylinder_index; // indicate o2 cylinder
+			else
+				cylinderindex = entry->cylinderindex;
+			current = pr_track_alloc(pressure, entry->sec);
+			track_pr[cylinderindex] = list_add(track_pr[cylinderindex], current);
+			continue;
+		}
+
+		if (!pressure) {
+			missing_pr = 1;
+			continue;
+		}
+		if (current)
+			current->end = pressure;
+
+		/* Was it continuous? */
+		if ((o2_flag) && (O2CYLINDER_PRESSURE(entry - 1))) // in the case of CCR o2 pressure
+			continue;
+		else if (SENSOR_PRESSURE(entry - 1)) // for all other cylinders
+			continue;
+
+		/* transmitter stopped transmitting cylinder pressure data */
+		current = pr_track_alloc(pressure, entry->sec);
+		if (cylinderindex >= 0)
+			track_pr[cylinderindex] = list_add(track_pr[cylinderindex], current);
+	}
+
+	if (missing_pr) {
+		fill_missing_tank_pressures(dive, pi, track_pr, o2_flag);
+	}
+
+#ifdef PRINT_PRESSURES_DEBUG
+	debug_print_pressures(pi);
+#endif
+
+GIVE_UP:
+	for (i = 0; i < MAX_CYLINDERS; i++)
+		list_free(track_pr[i]);
+}