cleanup: break out event-related code into event.[c|h]

In an effort to reduce the size of dive.h and dive.c, break out
the event related functions. Moreover event-names were handled
by the profile-code, collect that also in the new source files.

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

core/event.c

@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "event.h"
+#include "subsurface-string.h"
+
+#include <string.h>
+#include <stdlib.h>
+
+int event_is_gaschange(const struct event *ev)
+{
+	return ev->type == SAMPLE_EVENT_GASCHANGE ||
+		ev->type == SAMPLE_EVENT_GASCHANGE2;
+}
+
+bool event_is_divemodechange(const struct event *ev)
+{
+	return same_string(ev->name, "modechange");
+}
+
+struct event *clone_event(const struct event *src_ev)
+{
+	struct event *ev;
+	if (!src_ev)
+		return NULL;
+
+	size_t size = sizeof(*src_ev) + strlen(src_ev->name) + 1;
+	ev = (struct event*) malloc(size);
+	if (!ev)
+		exit(1);
+	memcpy(ev, src_ev, size);
+	ev->next = NULL;
+
+	return ev;
+}
+
+void free_events(struct event *ev)
+{
+	while (ev) {
+		struct event *next = ev->next;
+		free(ev);
+		ev = next;
+	}
+}
+
+struct event *create_event(unsigned int time, int type, int flags, int value, const char *name)
+{
+	int gas_index = -1;
+	struct event *ev;
+	unsigned int size, len = strlen(name);
+
+	size = sizeof(*ev) + len + 1;
+	ev = malloc(size);
+	if (!ev)
+		return NULL;
+	memset(ev, 0, size);
+	memcpy(ev->name, name, len);
+	ev->time.seconds = time;
+	ev->type = type;
+	ev->flags = flags;
+	ev->value = value;
+
+	/*
+	 * Expand the events into a sane format. Currently
+	 * just gas switches
+	 */
+	switch (type) {
+	case SAMPLE_EVENT_GASCHANGE2:
+		/* High 16 bits are He percentage */
+		ev->gas.mix.he.permille = (value >> 16) * 10;
+
+		/* Extension to the GASCHANGE2 format: cylinder index in 'flags' */
+		/* TODO: verify that gas_index < num_cylinders. */
+		if (flags > 0)
+			gas_index = flags-1;
+	/* Fallthrough */
+	case SAMPLE_EVENT_GASCHANGE:
+		/* Low 16 bits are O2 percentage */
+		ev->gas.mix.o2.permille = (value & 0xffff) * 10;
+		ev->gas.index = gas_index;
+		break;
+	}
+
+	return ev;
+}
+
+struct event *clone_event_rename(const struct event *ev, const char *name)
+{
+	return create_event(ev->time.seconds, ev->type, ev->flags, ev->value, name);
+}
+
+bool same_event(const struct event *a, const struct event *b)
+{
+	if (a->time.seconds != b->time.seconds)
+		return 0;
+	if (a->type != b->type)
+		return 0;
+	if (a->flags != b->flags)
+		return 0;
+	if (a->value != b->value)
+		return 0;
+	return !strcmp(a->name, b->name);
+}
+
+/* collect all event names and whether we display them */
+struct ev_select *ev_namelist = NULL;
+int evn_used = 0;
+static int evn_allocated = 0;
+
+void clear_events(void)
+{
+	for (int i = 0; i < evn_used; i++)
+		free(ev_namelist[i].ev_name);
+	evn_used = 0;
+}
+
+void remember_event(const char *eventname)
+{
+	int i = 0, len;
+
+	if (!eventname || (len = strlen(eventname)) == 0)
+		return;
+	while (i < evn_used) {
+		if (!strncmp(eventname, ev_namelist[i].ev_name, len))
+			return;
+		i++;
+	}
+	if (evn_used == evn_allocated) {
+		evn_allocated += 10;
+		ev_namelist = realloc(ev_namelist, evn_allocated * sizeof(struct ev_select));
+		if (!ev_namelist)
+			/* we are screwed, but let's just bail out */
+			return;
+	}
+	ev_namelist[evn_used].ev_name = strdup(eventname);
+	ev_namelist[evn_used].plot_ev = true;
+	evn_used++;
+}