cosmopolitan/libc/thread/mktls.c
2022-07-21 20:53:30 -07:00

56 lines
2.8 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2022 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/macros.internal.h"
#include "libc/mem/mem.h"
#include "libc/runtime/internal.h"
#include "libc/runtime/runtime.h"
#include "libc/str/str.h"
#include "libc/thread/spawn.h"
#include "libc/thread/thread.h"
#define _TLSZ ((intptr_t)_tls_size)
#define _TLDZ ((intptr_t)_tdata_size)
#define _TIBZ sizeof(struct cthread_descriptor_t)
#define _MEMZ ROUNDUP(_TLSZ + _TIBZ, alignof(struct cthread_descriptor_t))
/**
* Allocates thread-local storage memory for new thread.
* @return buffer that must be released with free()
*/
char *_mktls(char **out_tib) {
char *tls;
cthread_t tib;
// Allocate enough TLS memory for all the GNU Linuker (_tls_size)
// organized _Thread_local data, as well as Cosmpolitan Libc (64)
if (!(tls = calloc(1, _MEMZ))) return 0;
// set up thread information block
tib = (cthread_t)(tls + _MEMZ - _TIBZ);
tib->self = tib;
tib->self2 = tib;
tib->err = 0;
tib->tid = -1;
memmove(tls, _tdata_start, _TLDZ);
if (out_tib) {
*out_tib = (char *)tib;
}
return tls;
}