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, 2 insertions, 1 deletions

diff --git a/core/display.h b/core/display.h
index 3e3a9531e..8c6223be6 100644
--- a/core/display.h
+++ b/core/display.h
@@ -12,6 +12,7 @@ extern "C" {
  * and one-, two- and three-minute minimums and maximums */
 struct plot_info {
 	int nr;
+	int nr_cylinders;
 	int maxtime;
 	int meandepth, maxdepth;
 	int minpressure, maxpressure;
@@ -21,7 +22,7 @@ struct plot_info {
 	double endtempcoord;
 	double maxpp;
 	struct plot_data *entry;
-	struct plot_pressure_data *pressures; /* MAX_CYLINDERS blocks of nr entries. */
+	struct plot_pressure_data *pressures; /* cylinders.nr blocks of nr entries. */
 };
 
 extern struct divecomputer *select_dc(struct dive *);