#include <pthread.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include "int_lib.h"
#include "int_util.h"
#ifndef EMUTLS_USE_POSIX_MEMALIGN
#define EMUTLS_USE_POSIX_MEMALIGN 0
#endif
typedef struct __emutls_control {
size_t size;
size_t align;
union {
uintptr_t index;
void* address;
} object;
void* value;
} __emutls_control;
static __inline void *emutls_memalign_alloc(size_t align, size_t size) {
void *base;
#if EMUTLS_USE_POSIX_MEMALIGN
if (posix_memalign(&base, align, size) != 0)
abort();
#else
#define EXTRA_ALIGN_PTR_BYTES (align - 1 + sizeof(void*))
char* object;
if ((object = malloc(EXTRA_ALIGN_PTR_BYTES + size)) == NULL)
abort();
base = (void*)(((uintptr_t)(object + EXTRA_ALIGN_PTR_BYTES))
& ~(uintptr_t)(align - 1));
((void**)base)[-1] = object;
#endif
return base;
}
static __inline void emutls_memalign_free(void *base) {
#if EMUTLS_USE_POSIX_MEMALIGN
free(base);
#else
free(((void**)base)[-1]);
#endif
}
static __inline void *emutls_allocate_object(__emutls_control *control) {
typedef unsigned int gcc_word __attribute__((mode(word)));
typedef unsigned int gcc_pointer __attribute__((mode(pointer)));
COMPILE_TIME_ASSERT(sizeof(size_t) == sizeof(gcc_word));
COMPILE_TIME_ASSERT(sizeof(uintptr_t) == sizeof(gcc_pointer));
COMPILE_TIME_ASSERT(sizeof(uintptr_t) == sizeof(void*));
size_t size = control->size;
size_t align = control->align;
if (align < sizeof(void*))
align = sizeof(void*);
if ((align & (align - 1)) != 0)
abort();
void* base = emutls_memalign_alloc(align, size);
if (control->value)
memcpy(base, control->value, size);
else
memset(base, 0, size);
return base;
}
static pthread_mutex_t emutls_mutex = PTHREAD_MUTEX_INITIALIZER;
static size_t emutls_num_object = 0;
typedef struct emutls_address_array {
uintptr_t size;
void* data[];
} emutls_address_array;
static pthread_key_t emutls_pthread_key;
static void emutls_key_destructor(void* ptr) {
emutls_address_array* array = (emutls_address_array*)ptr;
uintptr_t i;
for (i = 0; i < array->size; ++i) {
if (array->data[i])
emutls_memalign_free(array->data[i]);
}
free(ptr);
}
static void emutls_init(void) {
if (pthread_key_create(&emutls_pthread_key, emutls_key_destructor) != 0)
abort();
}
static __inline uintptr_t emutls_get_index(__emutls_control *control) {
uintptr_t index = __atomic_load_n(&control->object.index, __ATOMIC_ACQUIRE);
if (!index) {
static pthread_once_t once = PTHREAD_ONCE_INIT;
pthread_once(&once, emutls_init);
pthread_mutex_lock(&emutls_mutex);
index = control->object.index;
if (!index) {
index = ++emutls_num_object;
__atomic_store_n(&control->object.index, index, __ATOMIC_RELEASE);
}
pthread_mutex_unlock(&emutls_mutex);
}
return index;
}
static __inline void emutls_check_array_set_size(emutls_address_array *array,
uintptr_t size) {
if (array == NULL)
abort();
array->size = size;
pthread_setspecific(emutls_pthread_key, (void*)array);
}
static __inline uintptr_t emutls_new_data_array_size(uintptr_t index) {
return ((index + 1 + 15) & ~((uintptr_t)15)) - 1;
}
static __inline emutls_address_array *
emutls_get_address_array(uintptr_t index) {
emutls_address_array* array = pthread_getspecific(emutls_pthread_key);
if (array == NULL) {
uintptr_t new_size = emutls_new_data_array_size(index);
array = calloc(new_size + 1, sizeof(void*));
emutls_check_array_set_size(array, new_size);
} else if (index > array->size) {
uintptr_t orig_size = array->size;
uintptr_t new_size = emutls_new_data_array_size(index);
array = realloc(array, (new_size + 1) * sizeof(void*));
if (array)
memset(array->data + orig_size, 0,
(new_size - orig_size) * sizeof(void*));
emutls_check_array_set_size(array, new_size);
}
return array;
}
void* __emutls_get_address(__emutls_control* control) {
uintptr_t index = emutls_get_index(control);
emutls_address_array* array = emutls_get_address_array(index);
if (array->data[index - 1] == NULL)
array->data[index - 1] = emutls_allocate_object(control);
return array->data[index - 1];
}