mifr/subsurface
1
0
Fork 0
mirror of https://github.com/subsurface/subsurface.git synced 2025-02-19 22:16:15 +00:00
Code Issues Projects Releases Packages Wiki Activity

Cleanup: return gasmix by value

Browse source 
Currently, get_gasmix_from_event() and get_gasmix() return pointers
to either static or to (possibly changing) dive data. This seems like
a dangerous practice and the returned data should be used immediately.

Instead, return the gasmix by value. This is in preparation of
const-ifying input parameters of a number of core functions, which
will ultimately let the merge() function take const-arguments in
preparation of undo of dive-merging.

On common 64-bit systems gasmix (two "int"s) is the size of a pointer
and can be returned in a register.

On 32-bit systems a pointer to the struct to be filled out will be
passed.

Since get_gasmix() now returns a value, the first invocation is
tested by a NULL-initialized "struct event *". Document this in
a comment.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
This commit is contained in:
Berthold Stoeger 2018-08-16 13:35:14 +02:00 • committed by Dirk Hohndel
parent b6187f73aa
commit f5b11daffd
10 changed files with 65 additions and 55 deletions
Download patch file Download diff file Expand all files Collapse all files

8
core/dive.h
View file

@ -585,7 +585,7 @@ extern void update_event_name(struct dive *d, struct event* event, const char *n
extern void add_extra_data(struct divecomputer *dc, const char *key, const char *value);
extern void per_cylinder_mean_depth(struct dive *dive, struct divecomputer *dc, int *mean, int *duration);
extern int get_cylinder_index(struct dive *dive, struct event *ev);
extern struct gasmix *get_gasmix_from_event(struct dive *, struct event *ev);
extern struct gasmix get_gasmix_from_event(struct dive *, struct event *ev);
extern int nr_cylinders(struct dive *dive);
extern int nr_weightsystems(struct dive *dive);
@ -718,7 +718,11 @@ extern void printdecotable(struct decostop *table);
extern struct event *get_next_event(struct event *event, const char *name);
extern struct gasmix *get_gasmix(struct dive *dive, struct divecomputer *dc, int time, struct event **evp, struct gasmix *gasmix);
/* Get gasmix at increasing timestamps.
* In "evp", pass a pointer to a "struct event *" which is NULL-initialized on first invocation.
* On subsequent calls, pass the same "evp" and the "gasmix" from previous calls.
*/
extern struct gasmix get_gasmix(struct dive *dive, struct divecomputer *dc, int time, struct event **evp, struct gasmix *gasmix);
/* these structs holds the information that
* describes the cylinders / weight systems.