1/* Copyright (C) 1991-2022 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18#include <sysdeps/generic/sysdep.h>
19#include <single-thread.h>
20#include <sys/syscall.h>
21#define HAVE_SYSCALLS
22
23/* Note that using a `PASTE' macro loses. */
24#define SYSCALL__(name, args) PSEUDO (__##name, name, args)
25#define SYSCALL(name, args) PSEUDO (name, name, args)
26
27#define __SYSCALL_CONCAT_X(a,b) a##b
28#define __SYSCALL_CONCAT(a,b) __SYSCALL_CONCAT_X (a, b)
29
30
31#define __INTERNAL_SYSCALL0(name) \
32 INTERNAL_SYSCALL (name, 0)
33#define __INTERNAL_SYSCALL1(name, a1) \
34 INTERNAL_SYSCALL (name, 1, a1)
35#define __INTERNAL_SYSCALL2(name, a1, a2) \
36 INTERNAL_SYSCALL (name, 2, a1, a2)
37#define __INTERNAL_SYSCALL3(name, a1, a2, a3) \
38 INTERNAL_SYSCALL (name, 3, a1, a2, a3)
39#define __INTERNAL_SYSCALL4(name, a1, a2, a3, a4) \
40 INTERNAL_SYSCALL (name, 4, a1, a2, a3, a4)
41#define __INTERNAL_SYSCALL5(name, a1, a2, a3, a4, a5) \
42 INTERNAL_SYSCALL (name, 5, a1, a2, a3, a4, a5)
43#define __INTERNAL_SYSCALL6(name, a1, a2, a3, a4, a5, a6) \
44 INTERNAL_SYSCALL (name, 6, a1, a2, a3, a4, a5, a6)
45#define __INTERNAL_SYSCALL7(name, a1, a2, a3, a4, a5, a6, a7) \
46 INTERNAL_SYSCALL (name, 7, a1, a2, a3, a4, a5, a6, a7)
47
48#define __INTERNAL_SYSCALL_NARGS_X(a,b,c,d,e,f,g,h,n,...) n
49#define __INTERNAL_SYSCALL_NARGS(...) \
50 __INTERNAL_SYSCALL_NARGS_X (__VA_ARGS__,7,6,5,4,3,2,1,0,)
51#define __INTERNAL_SYSCALL_DISP(b,...) \
52 __SYSCALL_CONCAT (b,__INTERNAL_SYSCALL_NARGS(__VA_ARGS__))(__VA_ARGS__)
53
54/* Issue a syscall defined by syscall number plus any other argument required.
55 It is similar to INTERNAL_SYSCALL macro, but without the need to pass the
56 expected argument number as second parameter. */
57#define INTERNAL_SYSCALL_CALL(...) \
58 __INTERNAL_SYSCALL_DISP (__INTERNAL_SYSCALL, __VA_ARGS__)
59
60#define __INTERNAL_SYSCALL_NCS0(name) \
61 INTERNAL_SYSCALL_NCS (name, 0)
62#define __INTERNAL_SYSCALL_NCS1(name, a1) \
63 INTERNAL_SYSCALL_NCS (name, 1, a1)
64#define __INTERNAL_SYSCALL_NCS2(name, a1, a2) \
65 INTERNAL_SYSCALL_NCS (name, 2, a1, a2)
66#define __INTERNAL_SYSCALL_NCS3(name, a1, a2, a3) \
67 INTERNAL_SYSCALL_NCS (name, 3, a1, a2, a3)
68#define __INTERNAL_SYSCALL_NCS4(name, a1, a2, a3, a4) \
69 INTERNAL_SYSCALL_NCS (name, 4, a1, a2, a3, a4)
70#define __INTERNAL_SYSCALL_NCS5(name, a1, a2, a3, a4, a5) \
71 INTERNAL_SYSCALL_NCS (name, 5, a1, a2, a3, a4, a5)
72#define __INTERNAL_SYSCALL_NCS6(name, a1, a2, a3, a4, a5, a6) \
73 INTERNAL_SYSCALL_NCS (name, 6, a1, a2, a3, a4, a5, a6)
74#define __INTERNAL_SYSCALL_NCS7(name, a1, a2, a3, a4, a5, a6, a7) \
75 INTERNAL_SYSCALL_NCS (name, 7, a1, a2, a3, a4, a5, a6, a7)
76
77#define INTERNAL_SYSCALL_NCS_CALL(...) \
78 __INTERNAL_SYSCALL_DISP (__INTERNAL_SYSCALL_NCS, __VA_ARGS__)
79
80#define __INLINE_SYSCALL0(name) \
81 INLINE_SYSCALL (name, 0)
82#define __INLINE_SYSCALL1(name, a1) \
83 INLINE_SYSCALL (name, 1, a1)
84#define __INLINE_SYSCALL2(name, a1, a2) \
85 INLINE_SYSCALL (name, 2, a1, a2)
86#define __INLINE_SYSCALL3(name, a1, a2, a3) \
87 INLINE_SYSCALL (name, 3, a1, a2, a3)
88#define __INLINE_SYSCALL4(name, a1, a2, a3, a4) \
89 INLINE_SYSCALL (name, 4, a1, a2, a3, a4)
90#define __INLINE_SYSCALL5(name, a1, a2, a3, a4, a5) \
91 INLINE_SYSCALL (name, 5, a1, a2, a3, a4, a5)
92#define __INLINE_SYSCALL6(name, a1, a2, a3, a4, a5, a6) \
93 INLINE_SYSCALL (name, 6, a1, a2, a3, a4, a5, a6)
94#define __INLINE_SYSCALL7(name, a1, a2, a3, a4, a5, a6, a7) \
95 INLINE_SYSCALL (name, 7, a1, a2, a3, a4, a5, a6, a7)
96
97#define __INLINE_SYSCALL_NARGS_X(a,b,c,d,e,f,g,h,n,...) n
98#define __INLINE_SYSCALL_NARGS(...) \
99 __INLINE_SYSCALL_NARGS_X (__VA_ARGS__,7,6,5,4,3,2,1,0,)
100#define __INLINE_SYSCALL_DISP(b,...) \
101 __SYSCALL_CONCAT (b,__INLINE_SYSCALL_NARGS(__VA_ARGS__))(__VA_ARGS__)
102
103/* Issue a syscall defined by syscall number plus any other argument
104 required. Any error will be handled using arch defined macros and errno
105 will be set accordingly.
106 It is similar to INLINE_SYSCALL macro, but without the need to pass the
107 expected argument number as second parameter. */
108#define INLINE_SYSCALL_CALL(...) \
109 __INLINE_SYSCALL_DISP (__INLINE_SYSCALL, __VA_ARGS__)
110
111#if IS_IN (rtld)
112/* All cancellation points are compiled out in the dynamic loader. */
113# define NO_SYSCALL_CANCEL_CHECKING 1
114#else
115# define NO_SYSCALL_CANCEL_CHECKING SINGLE_THREAD_P
116#endif
117
118#define SYSCALL_CANCEL(...) \
119 ({ \
120 long int sc_ret; \
121 if (NO_SYSCALL_CANCEL_CHECKING) \
122 sc_ret = INLINE_SYSCALL_CALL (__VA_ARGS__); \
123 else \
124 { \
125 int sc_cancel_oldtype = LIBC_CANCEL_ASYNC (); \
126 sc_ret = INLINE_SYSCALL_CALL (__VA_ARGS__); \
127 LIBC_CANCEL_RESET (sc_cancel_oldtype); \
128 } \
129 sc_ret; \
130 })
131
132/* Issue a syscall defined by syscall number plus any other argument
133 required. Any error will be returned unmodified (including errno). */
134#define INTERNAL_SYSCALL_CANCEL(...) \
135 ({ \
136 long int sc_ret; \
137 if (NO_SYSCALL_CANCEL_CHECKING) \
138 sc_ret = INTERNAL_SYSCALL_CALL (__VA_ARGS__); \
139 else \
140 { \
141 int sc_cancel_oldtype = LIBC_CANCEL_ASYNC (); \
142 sc_ret = INTERNAL_SYSCALL_CALL (__VA_ARGS__); \
143 LIBC_CANCEL_RESET (sc_cancel_oldtype); \
144 } \
145 sc_ret; \
146 })
147
148/* Machine-dependent sysdep.h files are expected to define the macro
149 PSEUDO (function_name, syscall_name) to emit assembly code to define the
150 C-callable function FUNCTION_NAME to do system call SYSCALL_NAME.
151 r0 and r1 are the system call outputs. MOVE(x, y) should be defined as
152 an instruction such that "MOVE(r1, r0)" works. ret should be defined
153 as the return instruction. */
154
155#ifndef SYS_ify
156#define SYS_ify(syscall_name) SYS_##syscall_name
157#endif
158
159/* Terminate a system call named SYM. This is used on some platforms
160 to generate correct debugging information. */
161#ifndef PSEUDO_END
162#define PSEUDO_END(sym)
163#endif
164#ifndef PSEUDO_END_NOERRNO
165#define PSEUDO_END_NOERRNO(sym) PSEUDO_END(sym)
166#endif
167#ifndef PSEUDO_END_ERRVAL
168#define PSEUDO_END_ERRVAL(sym) PSEUDO_END(sym)
169#endif
170
171/* Wrappers around system calls should normally inline the system call code.
172 But sometimes it is not possible or implemented and we use this code. */
173#ifndef INLINE_SYSCALL
174#define INLINE_SYSCALL(name, nr, args...) __syscall_##name (args)
175#endif
176

source code of glibc/sysdeps/unix/sysdep.h