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, 17 insertions, 15 deletions

diff --git a/core/datatrak.c b/core/datatrak.c
index 763b8cc8b..f9f577c73 100644
--- a/core/datatrak.c
+++ b/core/datatrak.c
@@ -317,12 +317,14 @@ static unsigned char *dt_dive_parser(unsigned char *runner, struct dive *dt_dive
 	 */
 	read_bytes(2);
 	if (tmp_2bytes != 0x7FFF) {
-		dt_dive->cylinder[0].type.size.mliter = tmp_2bytes * 10;
-		dt_dive->cylinder[0].type.description = strdup("");
-		dt_dive->cylinder[0].start.mbar = 200000;
-		dt_dive->cylinder[0].gasmix.he.permille = 0;
-		dt_dive->cylinder[0].gasmix.o2.permille = 210;
-		dt_dive->cylinder[0].manually_added = true;
+		cylinder_t cyl = { 0 };
+		cyl.type.size.mliter = tmp_2bytes * 10;
+		cyl.type.description = "";
+		cyl.start.mbar = 200000;
+		cyl.gasmix.he.permille = 0;
+		cyl.gasmix.o2.permille = 210;
+		cyl.manually_added = true;
+		add_cloned_cylinder(&dt_dive->cylinders, cyl);
 	}
 
 	/*
@@ -353,8 +355,8 @@ static unsigned char *dt_dive_parser(unsigned char *runner, struct dive *dt_dive
 	 * Air used in bar*100.
 	 */
 	read_bytes(2);
-	if (tmp_2bytes != 0x7FFF && dt_dive->cylinder[0].type.size.mliter)
-		dt_dive->cylinder[0].gas_used.mliter = lrint(dt_dive->cylinder[0].type.size.mliter * (tmp_2bytes / 100.0));
+	if (tmp_2bytes != 0x7FFF && dt_dive->cylinders.nr > 0)
+		dt_dive->cylinders.cylinders[0].gas_used.mliter = lrint(dt_dive->cylinders.cylinders[0].type.size.mliter * (tmp_2bytes / 100.0));
 
 	/*
 	 * Dive Type 1 -  Bit table. Subsurface don't have this record, but
@@ -529,11 +531,11 @@ static unsigned char *dt_dive_parser(unsigned char *runner, struct dive *dt_dive
 			free(compl_buffer);
 			goto bail;
 		}
-		if (is_nitrox)
-			dt_dive->cylinder[0].gasmix.o2.permille =
+		if (is_nitrox && dt_dive->cylinders.nr > 0)
+			dt_dive->cylinders.cylinders[0].gasmix.o2.permille =
 					lrint(membuf[23] & 0x0F ? 20.0 + 2 * (membuf[23] & 0x0F) : 21.0) * 10;
-		if (is_O2)
-			dt_dive->cylinder[0].gasmix.o2.permille = membuf[23] * 10;
+		if (is_O2 && dt_dive->cylinders.nr > 0)
+			dt_dive->cylinders.cylinders[0].gasmix.o2.permille = membuf[23] * 10;
 		free(compl_buffer);
 	}
 	JUMP(membuf, profile_length);
@@ -547,9 +549,9 @@ static unsigned char *dt_dive_parser(unsigned char *runner, struct dive *dt_dive
 		dt_dive->dc.deviceid = 0xffffffff;
 	create_device_node(dt_dive->dc.model, dt_dive->dc.deviceid, "", "", dt_dive->dc.model);
 	dt_dive->dc.next = NULL;
-	if (!is_SCR && dt_dive->cylinder[0].type.size.mliter) {
-		dt_dive->cylinder[0].end.mbar = dt_dive->cylinder[0].start.mbar -
-			((dt_dive->cylinder[0].gas_used.mliter / dt_dive->cylinder[0].type.size.mliter) * 1000);
+	if (!is_SCR && dt_dive->cylinders.nr > 0) {
+		dt_dive->cylinders.cylinders[0].end.mbar = dt_dive->cylinders.cylinders[0].start.mbar -
+			((dt_dive->cylinders.cylinders[0].gas_used.mliter / dt_dive->cylinders.cylinders[0].type.size.mliter) * 1000);
 	}
 	free(devdata);
 	return membuf;