Core: remove MAX_CYLINDERS restriction

Instead of using fixed size arrays, use a new cylinder_table structure.
The code copies the weightsystem code, but is significantly more complex
because cylinders are such an integral part of the core.

Two functions to access the cylinders were added:
get_cylinder() and get_or_create_cylinder()
The former does a simple array access and supposes that the cylinder
exists. The latter is used by the parser(s) and if a cylinder with
the given id does not exist, cylinders up to that id are generated.

One point will make C programmers cringe: the cylinder structure is
passed by value. This is due to the way the table-macros work. A
refactoring of the table macros is planned. It has to be noted that
the size of a cylinder_t is 64 bytes, i.e. 8 long words on a 64-bit
architecture, so passing on the stack is probably not even significantly
slower than passing as reference.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

1 files changed, 78 insertions, 39 deletions

diff --git a/core/equipment.c b/core/equipment.c
index d97ed6e4f..13e4a0486 100644
--- a/core/equipment.c
+++ b/core/equipment.c
@@ -24,6 +24,11 @@ static void free_weightsystem(weightsystem_t w)
 	free((void *)w.description);
 }
 
+static void free_cylinder(cylinder_t c)
+{
+	free((void *)c.type.description);
+}
+
 void copy_weights(const struct weightsystem_table *s, struct weightsystem_table *d)
 {
 	clear_weightsystem_table(d);
@@ -41,6 +46,16 @@ MAKE_REMOVE_FROM(weightsystem_table, weightsystems)
 //MAKE_REMOVE(weightsystem_table, weightsystem_t, weightsystem)
 MAKE_CLEAR_TABLE(weightsystem_table, weightsystems, weightsystem)
 
+/* cylinder table functions */
+//static MAKE_GET_IDX(cylinder_table, cylinder_t, cylinders)
+static MAKE_GROW_TABLE(cylinder_table, cylinder_t, cylinders)
+//static MAKE_GET_INSERTION_INDEX(cylinder_table, cylinder_t, cylinders, cylinder_less_than)
+MAKE_ADD_TO(cylinder_table, cylinder_t, cylinders)
+MAKE_REMOVE_FROM(cylinder_table, cylinders)
+//MAKE_SORT(cylinder_table, cylinder_t, cylinders, comp_cylinders)
+//MAKE_REMOVE(cylinder_table, cylinder_t, cylinder)
+MAKE_CLEAR_TABLE(cylinder_table, cylinders, cylinder)
+
 const char *cylinderuse_text[NUM_GAS_USE] = {
 	QT_TRANSLATE_NOOP("gettextFromC", "OC-gas"), QT_TRANSLATE_NOOP("gettextFromC", "diluent"), QT_TRANSLATE_NOOP("gettextFromC", "oxygen"), QT_TRANSLATE_NOOP("gettextFromC", "not used")
 };
@@ -104,34 +119,27 @@ void add_cloned_weightsystem(struct weightsystem_table *t, weightsystem_t ws)
 	add_to_weightsystem_table(t, t->nr, w_clone);
 }
 
-bool same_weightsystem(weightsystem_t w1, weightsystem_t w2)
-{
-	return w1.weight.grams == w2.weight.grams &&
-	       same_string(w1.description, w2.description);
-}
-
-bool cylinder_nodata(const cylinder_t *cyl)
+/* Add a clone of a cylinder to the end of a cylinder table.
+ * Cloned in means that the description-string is copied. */
+void add_cloned_cylinder(struct cylinder_table *t, cylinder_t cyl)
 {
-	return !cyl->type.size.mliter &&
-	       !cyl->type.workingpressure.mbar &&
-	       !cyl->type.description &&
-	       !cyl->gasmix.o2.permille &&
-	       !cyl->gasmix.he.permille &&
-	       !cyl->start.mbar &&
-	       !cyl->end.mbar &&
-	       !cyl->gas_used.mliter &&
-	       !cyl->deco_gas_used.mliter;
+	cyl.type.description = copy_string(cyl.type.description);
+	add_to_cylinder_table(t, t->nr, cyl);
 }
 
-static bool cylinder_nosamples(const cylinder_t *cyl)
+bool same_weightsystem(weightsystem_t w1, weightsystem_t w2)
 {
-	return !cyl->sample_start.mbar &&
-	       !cyl->sample_end.mbar;
+	return w1.weight.grams == w2.weight.grams &&
+	       same_string(w1.description, w2.description);
 }
 
-bool cylinder_none(const cylinder_t *cyl)
+bool same_cylinder(cylinder_t cyl1, cylinder_t cyl2)
 {
-	return cylinder_nodata(cyl) && cylinder_nosamples(cyl);
+	return same_string(cyl1.type.description, cyl2.type.description) &&
+	       same_gasmix(cyl1.gasmix, cyl2.gasmix) &&
+	       cyl1.start.mbar == cyl2.start.mbar &&
+	       cyl1.end.mbar == cyl2.end.mbar &&
+	       cyl1.cylinder_use == cyl2.cylinder_use;
 }
 
 void get_gas_string(struct gasmix gasmix, char *text, int len)
@@ -161,18 +169,16 @@ int gas_volume(const cylinder_t *cyl, pressure_t p)
 	return lrint(cyl->type.size.mliter * bar_to_atm(bar) / z_factor);
 }
 
-int find_best_gasmix_match(struct gasmix mix, const cylinder_t array[])
+int find_best_gasmix_match(struct gasmix mix, const struct cylinder_table *cylinders)
 {
 	int i;
 	int best = -1, score = INT_MAX;
 
-	for (i = 0; i < MAX_CYLINDERS; i++) {
+	for (i = 0; i < cylinders->nr; i++) {
 		const cylinder_t *match;
 		int distance;
 
-		match = array + i;
-		if (cylinder_nodata(match))
-			continue;
+		match = cylinders->cylinders + i;
 		distance = gasmix_distance(mix, match->gasmix);
 		if (distance >= score)
 			continue;
@@ -258,10 +264,7 @@ struct ws_info_t ws_info[MAX_WS_INFO] = {
 
 void remove_cylinder(struct dive *dive, int idx)
 {
-	cylinder_t *cyl = dive->cylinder + idx;
-	int nr = MAX_CYLINDERS - idx - 1;
-	memmove(cyl, cyl + 1, nr * sizeof(*cyl));
-	memset(cyl + nr, 0, sizeof(*cyl));
+	remove_from_cylinder_table(&dive->cylinders, idx);
 }
 
 void remove_weightsystem(struct dive *dive, int idx)
@@ -275,10 +278,8 @@ void reset_cylinders(struct dive *dive, bool track_gas)
 {
 	pressure_t decopo2 = {.mbar = prefs.decopo2};
 
-	for (int i = 0; i < MAX_CYLINDERS; i++) {
-		cylinder_t *cyl = &dive->cylinder[i];
-		if (cylinder_none(cyl))
-			continue;
+	for (int i = 0; i < dive->cylinders.nr; i++) {
+		cylinder_t *cyl = &dive->cylinders.cylinders[i];
 		if (cyl->depth.mm == 0) /* if the gas doesn't give a mod, calculate based on prefs */
 			cyl->depth = gas_mod(cyl->gasmix, decopo2, dive, M_OR_FT(3,10));
 		if (track_gas)
@@ -290,7 +291,7 @@ void reset_cylinders(struct dive *dive, bool track_gas)
 
 static void copy_cylinder_type(const cylinder_t *s, cylinder_t *d)
 {
-	free(d->type.description);
+	free_cylinder(*d);
 	d->type = s->type;
 	d->type.description = s->type.description ? strdup(s->type.description) : NULL;
 	d->gasmix = s->gasmix;
@@ -306,16 +307,54 @@ void copy_cylinder_types(const struct dive *s, struct dive *d)
 	if (!s || !d)
 		return;
 
-	for (i = 0; i < MAX_CYLINDERS; i++)
-		copy_cylinder_type(s->cylinder + i, d->cylinder + i);
+	for (i = 0; i < s->cylinders.nr && i < d->cylinders.nr; i++)
+		copy_cylinder_type(s->cylinders.cylinders + i, d->cylinders.cylinders + i);
+
+	for ( ; i < s->cylinders.nr; i++)
+		add_cloned_cylinder(&d->cylinders, s->cylinders.cylinders[i]);
+}
+
+void add_empty_cylinder(struct cylinder_table *t)
+{
+	cylinder_t cyl = { 0 };
+	cyl.type.description = strdup("");
+	add_to_cylinder_table(t, t->nr, cyl);
+}
+
+/* access to cylinders is controlled by two functions:
+ * - get_cylinder() returns the cylinder of a dive and supposes that
+ *   the cylinder with the given index exists. If it doesn't, an error
+ *   message is printed and NULL returned.
+ * - get_or_create_cylinder() creates an empty cylinder if it doesn't exist.
+ *   Multiple cylinders might be created if the index is bigger than the
+ *   number of existing cylinders
+ */
+cylinder_t *get_cylinder(const struct dive *d, int idx)
+{
+	if (idx < 0 || idx >= d->cylinders.nr) {
+		fprintf(stderr, "Warning: accessing invalid cylinder %d (%d existing)\n", idx, d->cylinders.nr);
+		return NULL;
+	}
+	return &d->cylinders.cylinders[idx];
+}
+
+cylinder_t *get_or_create_cylinder(struct dive *d, int idx)
+{
+	if (idx < 0) {
+		fprintf(stderr, "Warning: accessing invalid cylinder %d\n", idx);
+		return NULL;
+	}
+	while (idx >= d->cylinders.nr)
+		add_empty_cylinder(&d->cylinders);
+	return &d->cylinders.cylinders[idx];
 }
 
 #ifdef DEBUG_CYL
 void dump_cylinders(struct dive *dive, bool verbose)
 {
 	printf("Cylinder list:\n");
-	for (int i = 0; i < MAX_CYLINDERS; i++) {
-		cylinder_t *cyl = &dive->cylinder[i];
+	for (int i = 0; i < dive->cylinders; i++) {
+		cylinder_t *cyl = &dive->cylinders.cylinders[i];
 
 		printf("%02d: Type     %s, %3.1fl, %3.0fbar\n", i, cyl->type.description, cyl->type.size.mliter / 1000.0, cyl->type.workingpressure.mbar / 1000.0);
 		printf("    Gasmix   O2 %2.0f%% He %2.0f%%\n", cyl->gasmix.o2.permille / 10.0, cyl->gasmix.he.permille / 10.0);