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#include <unistd.h>
#include <pthread.h>
#include "atomic.h"
#include "syscall.h"
#include "psxglue.h"
#include "pthread_impl.h"
extern const struct __ldso_vtbl * __ldso_vtbl;
extern const struct __psx_vtbl * __psx_vtbl;
typedef int __app_main();
typedef int __pthread_surrogate_routine(struct pthread *);
static int __pthread_surrogate_init(struct pthread * self);
extern int __libc_start_main(
void * main,
int argc,
char ** argv);
static void (*__global_ctors_fn)();
static void (*__global_dtors_fn)();
void _init()
{
__global_ctors_fn();
}
void _fini()
{
__global_dtors_fn();
}
struct __tls {
void * pad[16/sizeof(void *)];
struct pthread pt;
} __builtin_tls = {{0}};
void __init_tls (size_t * auxv)
{
#define T __builtin_tls
__set_thread_area(&T.pt);
T.pt.self = &T.pt;
T.pt.locale = &libc.global_locale;
T.pt.tid = __syscall(SYS_set_tid_address, &T.pt.tid);
libc.can_do_threads = 1;
libc.tls_size = sizeof(struct __tls);
};
void __libc_entry_routine(
__app_main * __main,
__psx_init_routine * __psx_init,
int options)
{
int argc;
char ** argv;
char ** envp;
struct __psx_context ctx;
/* ctx init */
ctx.size = sizeof(ctx);
ctx.options = options;
ctx.pthread_create_fn = pthread_create;
ctx.pthread_surrogate_fn= __pthread_surrogate_init;
/* __psx_init must succeed... */
if (__psx_init(&argc,&argv,&envp,&ctx))
a_crash();
/* ...and conform */
else if (envp != argv + (argc + 1))
a_crash();
/* write once */
__syscall_vtbl = (unsigned long **)ctx.sys_vtbl;
__ldso_vtbl = ctx.ldso_vtbl;
__psx_vtbl = ctx.psx_vtbl;
__teb_sys_idx = ctx.teb_sys_idx;
__teb_libc_idx = ctx.teb_libc_idx;
/* surrogate init/fini arrays */
__global_ctors_fn = __psx_vtbl->do_global_ctors_fn;
__global_dtors_fn = __psx_vtbl->do_global_dtors_fn;
/* enter libc */
__psx_vtbl->start_main(__main,argc,argv,__libc_start_main);
/* guard */
a_crash();
}
static int __pthread_surrogate_init(struct pthread * self)
{
/**
* invoked by psxscl upon creation of a surrogate libc
* thread, which in turn may only call pthread_create();
*
* the purpose of this mecahnism is to support a scenario
* where a third-party library creates a non-posix thread
* which then calls, be it directly or via a callback
* function, a libc api that depends on a valid
* pthread_self.
*
* self: a pointer to an already zero'ed memory page
*
* struct pthread relevant members:
* --------------------------------
* cancel (already zero)
* canary (already zero)
*
* pthread_create() reference:
* 1a47ed15eebf96d0c8d5de4aea54108bc8cc3f53
**/
return 0;
}
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