1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
/**************************************************************************/
/* mmglue: midipix architecture- and target-specific bits for musl libc */
/* Copyright (C) 2013--2023 SysDeer Technologies, LLC */
/* Released under the Standard MIT License; see COPYING.MMGLUE. */
/**************************************************************************/
#include <unistd.h>
#include <stdint.h>
#include <pthread.h>
#include "atomic.h"
#include "syscall.h"
#include "psxglue.h"
#include "pthread_impl.h"
volatile int __thread_list_lock;
extern const struct __ldso_vtbl * __ldso_vtbl;
extern const struct __psx_vtbl * __psx_vtbl;
extern const struct __seh_vtbl * __eh_vtbl;
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.sysinfo = __sysinfo;
T.pt.detach_state = DT_JOINABLE;
T.pt.locale = &libc.global_locale;
T.pt.robust_list.head = &T.pt.robust_list.head;
libc.can_do_threads = 1;
libc.tls_size = sizeof(struct __tls);
#if defined(__LIBC_TD_TID_ADDR_TID)
T.pt.tid = __syscall(SYS_set_tid_address, &T.pt.tid);
#elif defined(__LIBC_TD_TID_ADDR_JOIN_FUTEX)
T.pt.join_futex = -1;
T.pt.tid = __syscall(SYS_set_tid_address, &T.pt.join_futex);
#elif defined(__LIBC_TD_TID_ADDR_DETACH_STATE)
T.pt.tid = __syscall(SYS_set_tid_address, &T.pt.detach_state);
#elif defined(__LIBC_TD_TID_ADDR_THREAD_LIST_LOCK)
T.pt.tid = __syscall(SYS_set_tid_address, &T.pt.detach_state);
T.pt.next = &T.pt;
T.pt.prev = &T.pt;
#else
#error could not detect tid address logic.
#endif
};
void __libc_entry_routine(
int (*main)(),
__psx_init_routine * __psx_init,
const unsigned short * __ctty,
int options)
{
int argc;
char ** argv;
char ** envp;
struct __psx_context ctx;
/* ctx init */
ctx.size = sizeof(ctx);
ctx.options = options;
ctx.usrmain = main;
ctx.ldsoaddr = _init;
ctx.ctty = __ctty;
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;
__eh_vtbl = ctx.seh_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->mm_start_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;
}
|
