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#include <camellia/errno.h>
#include <camellia/flags.h>
#include <kernel/handleset.h>
#include <kernel/malloc.h>
#include <kernel/panic.h>
HandleSet *
hs_init(void)
{
HandleSet *hs = kzalloc(sizeof *hs, "handles");
hs->refcount = 1;
return hs;
}
HandleSet *
hs_copy(HandleSet *from)
{
HandleSet *hs = hs_init();
assert(from);
for (hid_t i = 0; i < HANDLE_MAX; i++) {
hs->h[i] = from->h[i];
if (hs->h[i]) {
hs->h[i]->refcount++;
}
}
return hs;
}
void
hs_unref(HandleSet *hs)
{
assert(hs);
assert(hs->refcount != 0);
hs->refcount--;
if (hs->refcount == 0) {
for (hid_t i = 0; i < HANDLE_MAX; i++) {
hs_close(hs, i);
}
kfree(hs);
}
}
hid_t
hs_findfree(HandleSet *hs, hid_t start)
{
if (start < 0) start = 0;
for (hid_t i = start; i < HANDLE_MAX; i++) {
if (hs->h[i] == NULL) {
return i;
}
}
return -1;
}
Handle *
hs_get(HandleSet *hs, hid_t id)
{
if (0 <= id && id < HANDLE_MAX) {
return hs->h[id];
} else {
return NULL;
}
}
hid_t
hs_hinit(HandleSet *hs, enum handle_type type, Handle **hp)
{
hid_t hid = hs_findfree(hs, 1);
if (hid < 0) return -1;
hs->h[hid] = handle_init(type);
if (hp) *hp = hs->h[hid];
return hid;
}
hid_t
hs_dup(HandleSet *hs, hid_t from, hid_t to, int flags)
{
Handle *fromh, **toh;
if (to < 0 || (flags & DUP_SEARCH)) {
to = hs_findfree(hs, to);
if (to < 0) return -EMFILE;
} else if (to >= HANDLE_MAX) {
return -EBADF;
}
if (to == from) return to;
toh = &hs->h[to];
fromh = hs_get(hs, from);
if (*toh) handle_close(*toh);
if (flags & (DUP_RDONLY | DUP_WRONLY)) {
if (!fromh || fromh->type != HANDLE_FILE) {
/* only errors out after closing the old handle */
*toh = NULL;
return -ENOSYS;
}
/* figure out if we need a need handle */
bool different = false;
different = different || ((flags & DUP_RDONLY) && fromh->writeable);
different = different || ((flags & DUP_WRONLY) && fromh->readable);
if (different) {
Handle *new = handle_init(HANDLE_FILE);
new->backend = fromh->backend;
if (new->backend) new->backend->usehcnt++;
new->file_id = fromh->file_id;
new->readable = fromh->readable && !(flags & DUP_WRONLY);
new->writeable = fromh->writeable && !(flags & DUP_RDONLY);
new->base = fromh;
fromh->refcount++;
*toh = new;
return to;
}
}
*toh = fromh;
if (fromh) fromh->refcount++;
return to;
}
Handle *
hs_take(HandleSet *hs, hid_t hid)
{
if (hid < 0 || hid >= HANDLE_MAX) {
return NULL;
}
Handle *h = hs->h[hid];
hs->h[hid] = NULL;
return h;
}
hid_t
hs_put(HandleSet *hs, Handle *h)
{
assert(h);
hid_t hid = hs_findfree(hs, 1);
if (hid < 0) {
handle_close(h);
return hid;
}
hs->h[hid] = h;
return hid;
}
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