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#include <__thread.h>
#include <asm/prctl.h>
#include <elf.h>
#include <libc.h>
#include <string.h>
#include <sys/mman.h>
#include <syscall.h>
#define ALIGN_DOWN(x, a) ((x) & ~((a) - 1))
#define ALIGN_UP(x, a) (((x) + (a) - 1) & ~((a) - 1))
static struct tls __libc_tls = { 0 };
static struct __thread_self __libc_thread;
volatile int __libc_tid;
void __init_tls(void)
{
int r;
void *mem;
size_t base;
unsigned char *p;
Elf64_Phdr *tls_phdr;
struct __thread_self *thrd;
base = 0;
tls_phdr = 0;
p = (void *)__libc.auxv[AT_PHDR];
for (size_t n = __libc.auxv[AT_PHNUM]; n > 0; n--, p += __libc.auxv[AT_PHENT]) {
Elf64_Phdr *phdr = (Elf64_Phdr *)p;
if (phdr->p_type == PT_PHDR) {
base = __libc.auxv[AT_PHDR] - phdr->p_vaddr;
} else if (phdr->p_type == PT_TLS) {
tls_phdr = phdr;
}
}
if (tls_phdr) {
__libc_tls.data = (void *)(base + tls_phdr->p_vaddr);
__libc_tls.length = tls_phdr->p_filesz;
__libc_tls.size = tls_phdr->p_memsz;
__libc_tls.align = tls_phdr->p_align;
}
if (__libc_tls.size != 0) {
void *tls_mem;
size_t tls_size = __libc_tls.size + sizeof(struct __thread_self);
tls_size = (tls_size + __libc_tls.align - 1) & ~(__libc_tls.align - 1);
mem = mmap(0, tls_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
panic_if(mem == MAP_FAILED, "mmap failed");
__libc.tls.base = mem;
__libc.tls.size = tls_size;
thrd = (struct __thread_self *)mem;
tls_mem = (unsigned char *)mem + sizeof(struct __thread_self);
if (tls_phdr->p_filesz > 0) {
memcpy(tls_mem, (void *)tls_phdr->p_vaddr, tls_phdr->p_filesz);
memset(tls_mem + tls_phdr->p_filesz, 0, tls_phdr->p_memsz - tls_phdr->p_filesz);
} else {
memset(tls_mem, 0, tls_phdr->p_memsz);
}
r = syscall(arch_prctl, ARCH_SET_FS, mem + sizeof(struct __thread_self));
panic_if(r < 0, "arch_prctl(SET_FS) failed");
} else {
__libc.tls.base = NULL;
thrd = &__libc_thread;
}
r = syscall(set_tid_address, &__libc_tid);
panic_if(r < 0, "set_tid_address failed");
thrd->tid = r;
}
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