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// Example translated to C from https://en.cppreference.com/w/cpp/memory/shared_ptr
#include <stdio.h>
#include <threads.h>
#include <time.h>
struct Base
{
int value;
} typedef Base;
#define i_type BaseArc
#define i_val Base
#define i_valdrop(x) printf("Drop Base: %d\n", (x)->value)
#define i_opt c_no_cmp
#include <stc/carc.h>
mtx_t mtx;
void* thr(BaseArc* p)
{
struct timespec one_sec = {.tv_sec=1};
thrd_sleep(&one_sec, NULL);
BaseArc lp = BaseArc_clone(*p); // thread-safe, even though the
// shared use_count is incremented
c_autoscope (mtx_lock(&mtx), mtx_unlock(&mtx))
{
printf("local pointer in a thread:\n"
" p.get() = %p, p.use_count() = %ld\n", (void*)lp.get, BaseArc_use_count(lp));
/* safe to modify base here */
lp.get->value += 1;
}
BaseArc_drop(&lp);
BaseArc_drop(p);
return NULL;
}
int main()
{
BaseArc p = BaseArc_make((Base){0});
mtx_init(&mtx, mtx_plain);
printf("Created a shared Base\n"
" p.get() = %p, p.use_count() = %ld\n", (void*)p.get, BaseArc_use_count(p));
enum {N = 3};
struct { thrd_t t; BaseArc p; } task[N];
c_forrange (i, N) {
task[i].p = BaseArc_clone(p);
thrd_create(&task[i].t, (thrd_start_t)thr, &task[i].p);
}
BaseArc_reset(&p);
printf("Shared ownership between %d threads and released\n"
"ownership from main:\n"
" p.get() = %p, p.use_count() = %ld\n", N, (void*)p.get, BaseArc_use_count(p));
c_forrange (i, N) thrd_join(task[i].t, NULL);
printf("All threads completed, the last one deleted Base\n");
}
#ifdef STC_TINYCTHREAD_H_
#include "../src/threads.c"
#endif
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