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
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
|
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
* Compatibility interface for userspace libc header coordination:
*
* Define compatibility macros that are used to control the inclusion or
* exclusion of UAPI structures and definitions in coordination with another
* userspace C library.
*
* This header is intended to solve the problem of UAPI definitions that
* conflict with userspace definitions. If a UAPI header has such conflicting
* definitions then the solution is as follows:
*
* * Synchronize the UAPI header and the libc headers so either one can be
* used and such that the ABI is preserved. If this is not possible then
* no simple compatibility interface exists (you need to write translating
* wrappers and rename things) and you can't use this interface.
*
* Then follow this process:
*
* (a) Include libc-compat.h in the UAPI header.
* e.g. #include <linux/libc-compat.h>
* This include must be as early as possible.
*
* (b) In libc-compat.h add enough code to detect that the comflicting
* userspace libc header has been included first.
*
* (c) If the userspace libc header has been included first define a set of
* guard macros of the form __UAPI_DEF_FOO and set their values to 1, else
* set their values to 0.
*
* (d) Back in the UAPI header with the conflicting definitions, guard the
* definitions with:
* #if __UAPI_DEF_FOO
* ...
* #endif
*
* This fixes the situation where the linux headers are included *after* the
* libc headers. To fix the problem with the inclusion in the other order the
* userspace libc headers must be fixed like this:
*
* * For all definitions that conflict with kernel definitions wrap those
* defines in the following:
* #if !__UAPI_DEF_FOO
* ...
* #endif
*
* This prevents the redefinition of a construct already defined by the kernel.
*/
#ifndef _UAPI_LIBC_COMPAT_H
#define _UAPI_LIBC_COMPAT_H
/* We have included glibc headers... */
#if defined(__GLIBC__)
/* Coordinate with glibc net/if.h header. */
#if defined(_NET_IF_H) && defined(__USE_MISC)
/* GLIBC headers included first so don't define anything
* that would already be defined. */
#define __UAPI_DEF_IF_IFCONF 0
#define __UAPI_DEF_IF_IFMAP 0
#define __UAPI_DEF_IF_IFNAMSIZ 0
#define __UAPI_DEF_IF_IFREQ 0
/* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS 0
/* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */
#ifndef __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1
#endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO */
#else /* _NET_IF_H */
/* Linux headers included first, and we must define everything
* we need. The expectation is that glibc will check the
* __UAPI_DEF_* defines and adjust appropriately. */
#define __UAPI_DEF_IF_IFCONF 1
#define __UAPI_DEF_IF_IFMAP 1
#define __UAPI_DEF_IF_IFNAMSIZ 1
#define __UAPI_DEF_IF_IFREQ 1
/* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS 1
/* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1
#endif /* _NET_IF_H */
/* Coordinate with glibc netinet/in.h header. */
#if defined(_NETINET_IN_H)
/* GLIBC headers included first so don't define anything
* that would already be defined. */
#define __UAPI_DEF_IN_ADDR 0
#define __UAPI_DEF_IN_IPPROTO 0
#define __UAPI_DEF_IN_PKTINFO 0
#define __UAPI_DEF_IP_MREQ 0
#define __UAPI_DEF_SOCKADDR_IN 0
#define __UAPI_DEF_IN_CLASS 0
#define __UAPI_DEF_IN6_ADDR 0
/* The exception is the in6_addr macros which must be defined
* if the glibc code didn't define them. This guard matches
* the guard in glibc/inet/netinet/in.h which defines the
* additional in6_addr macros e.g. s6_addr16, and s6_addr32. */
#if defined(__USE_MISC) || defined (__USE_GNU)
#define __UAPI_DEF_IN6_ADDR_ALT 0
#else
#define __UAPI_DEF_IN6_ADDR_ALT 1
#endif
#define __UAPI_DEF_SOCKADDR_IN6 0
#define __UAPI_DEF_IPV6_MREQ 0
#define __UAPI_DEF_IPPROTO_V6 0
#define __UAPI_DEF_IPV6_OPTIONS 0
#define __UAPI_DEF_IN6_PKTINFO 0
#define __UAPI_DEF_IP6_MTUINFO 0
#else
/* Linux headers included first, and we must define everything
* we need. The expectation is that glibc will check the
* __UAPI_DEF_* defines and adjust appropriately. */
#define __UAPI_DEF_IN_ADDR 1
#define __UAPI_DEF_IN_IPPROTO 1
#define __UAPI_DEF_IN_PKTINFO 1
#define __UAPI_DEF_IP_MREQ 1
#define __UAPI_DEF_SOCKADDR_IN 1
#define __UAPI_DEF_IN_CLASS 1
#define __UAPI_DEF_IN6_ADDR 1
/* We unconditionally define the in6_addr macros and glibc must
* coordinate. */
#define __UAPI_DEF_IN6_ADDR_ALT 1
#define __UAPI_DEF_SOCKADDR_IN6 1
#define __UAPI_DEF_IPV6_MREQ 1
#define __UAPI_DEF_IPPROTO_V6 1
#define __UAPI_DEF_IPV6_OPTIONS 1
#define __UAPI_DEF_IN6_PKTINFO 1
#define __UAPI_DEF_IP6_MTUINFO 1
#endif /* _NETINET_IN_H */
/* Coordinate with glibc netipx/ipx.h header. */
#if defined(__NETIPX_IPX_H)
#define __UAPI_DEF_SOCKADDR_IPX 0
#define __UAPI_DEF_IPX_ROUTE_DEFINITION 0
#define __UAPI_DEF_IPX_INTERFACE_DEFINITION 0
#define __UAPI_DEF_IPX_CONFIG_DATA 0
#define __UAPI_DEF_IPX_ROUTE_DEF 0
#else /* defined(__NETIPX_IPX_H) */
#define __UAPI_DEF_SOCKADDR_IPX 1
#define __UAPI_DEF_IPX_ROUTE_DEFINITION 1
#define __UAPI_DEF_IPX_INTERFACE_DEFINITION 1
#define __UAPI_DEF_IPX_CONFIG_DATA 1
#define __UAPI_DEF_IPX_ROUTE_DEF 1
#endif /* defined(__NETIPX_IPX_H) */
/* Definitions for xattr.h */
#if defined(_SYS_XATTR_H)
#define __UAPI_DEF_XATTR 0
#else
#define __UAPI_DEF_XATTR 1
#endif
/* If we did not see any headers from any supported C libraries,
* or we are being included in the kernel, then define everything
* that we need. Check for previous __UAPI_* definitions to give
* unsupported C libraries a way to opt out of any kernel definition. */
#else /* !defined(__GLIBC__) */
/* Definitions for if.h */
#ifndef __UAPI_DEF_IF_IFCONF
#define __UAPI_DEF_IF_IFCONF 1
#endif
#ifndef __UAPI_DEF_IF_IFMAP
#define __UAPI_DEF_IF_IFMAP 1
#endif
#ifndef __UAPI_DEF_IF_IFNAMSIZ
#define __UAPI_DEF_IF_IFNAMSIZ 1
#endif
#ifndef __UAPI_DEF_IF_IFREQ
#define __UAPI_DEF_IF_IFREQ 1
#endif
/* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */
#ifndef __UAPI_DEF_IF_NET_DEVICE_FLAGS
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS 1
#endif
/* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */
#ifndef __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1
#endif
/* Definitions for in.h */
#ifndef __UAPI_DEF_IN_ADDR
#define __UAPI_DEF_IN_ADDR 1
#endif
#ifndef __UAPI_DEF_IN_IPPROTO
#define __UAPI_DEF_IN_IPPROTO 1
#endif
#ifndef __UAPI_DEF_IN_PKTINFO
#define __UAPI_DEF_IN_PKTINFO 1
#endif
#ifndef __UAPI_DEF_IP_MREQ
#define __UAPI_DEF_IP_MREQ 1
#endif
#ifndef __UAPI_DEF_SOCKADDR_IN
#define __UAPI_DEF_SOCKADDR_IN 1
#endif
#ifndef __UAPI_DEF_IN_CLASS
#define __UAPI_DEF_IN_CLASS 1
#endif
/* Definitions for in6.h */
#ifndef __UAPI_DEF_IN6_ADDR
#define __UAPI_DEF_IN6_ADDR 1
#endif
#ifndef __UAPI_DEF_IN6_ADDR_ALT
#define __UAPI_DEF_IN6_ADDR_ALT 1
#endif
#ifndef __UAPI_DEF_SOCKADDR_IN6
#define __UAPI_DEF_SOCKADDR_IN6 1
#endif
#ifndef __UAPI_DEF_IPV6_MREQ
#define __UAPI_DEF_IPV6_MREQ 1
#endif
#ifndef __UAPI_DEF_IPPROTO_V6
#define __UAPI_DEF_IPPROTO_V6 1
#endif
#ifndef __UAPI_DEF_IPV6_OPTIONS
#define __UAPI_DEF_IPV6_OPTIONS 1
#endif
#ifndef __UAPI_DEF_IN6_PKTINFO
#define __UAPI_DEF_IN6_PKTINFO 1
#endif
#ifndef __UAPI_DEF_IP6_MTUINFO
#define __UAPI_DEF_IP6_MTUINFO 1
#endif
/* Definitions for ipx.h */
#ifndef __UAPI_DEF_SOCKADDR_IPX
#define __UAPI_DEF_SOCKADDR_IPX 1
#endif
#ifndef __UAPI_DEF_IPX_ROUTE_DEFINITION
#define __UAPI_DEF_IPX_ROUTE_DEFINITION 1
#endif
#ifndef __UAPI_DEF_IPX_INTERFACE_DEFINITION
#define __UAPI_DEF_IPX_INTERFACE_DEFINITION 1
#endif
#ifndef __UAPI_DEF_IPX_CONFIG_DATA
#define __UAPI_DEF_IPX_CONFIG_DATA 1
#endif
#ifndef __UAPI_DEF_IPX_ROUTE_DEF
#define __UAPI_DEF_IPX_ROUTE_DEF 1
#endif
/* Definitions for xattr.h */
#ifndef __UAPI_DEF_XATTR
#define __UAPI_DEF_XATTR 1
#endif
#endif /* __GLIBC__ */
/* Definitions for if_ether.h */
/* allow libcs like musl to deactivate this, glibc does not implement this. */
#ifndef __UAPI_DEF_ETHHDR
#define __UAPI_DEF_ETHHDR 1
#endif
#endif /* _UAPI_LIBC_COMPAT_H */
|
