logo

oasis-root

Compiled tree of Oasis Linux based on own branch at <https://hacktivis.me/git/oasis/> git clone https://anongit.hacktivis.me/git/oasis-root.git

libc-compat.h (7289B)


  1. /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
  2. /*
  3. * Compatibility interface for userspace libc header coordination:
  4. *
  5. * Define compatibility macros that are used to control the inclusion or
  6. * exclusion of UAPI structures and definitions in coordination with another
  7. * userspace C library.
  8. *
  9. * This header is intended to solve the problem of UAPI definitions that
  10. * conflict with userspace definitions. If a UAPI header has such conflicting
  11. * definitions then the solution is as follows:
  12. *
  13. * * Synchronize the UAPI header and the libc headers so either one can be
  14. * used and such that the ABI is preserved. If this is not possible then
  15. * no simple compatibility interface exists (you need to write translating
  16. * wrappers and rename things) and you can't use this interface.
  17. *
  18. * Then follow this process:
  19. *
  20. * (a) Include libc-compat.h in the UAPI header.
  21. * e.g. #include <linux/libc-compat.h>
  22. * This include must be as early as possible.
  23. *
  24. * (b) In libc-compat.h add enough code to detect that the comflicting
  25. * userspace libc header has been included first.
  26. *
  27. * (c) If the userspace libc header has been included first define a set of
  28. * guard macros of the form __UAPI_DEF_FOO and set their values to 1, else
  29. * set their values to 0.
  30. *
  31. * (d) Back in the UAPI header with the conflicting definitions, guard the
  32. * definitions with:
  33. * #if __UAPI_DEF_FOO
  34. * ...
  35. * #endif
  36. *
  37. * This fixes the situation where the linux headers are included *after* the
  38. * libc headers. To fix the problem with the inclusion in the other order the
  39. * userspace libc headers must be fixed like this:
  40. *
  41. * * For all definitions that conflict with kernel definitions wrap those
  42. * defines in the following:
  43. * #if !__UAPI_DEF_FOO
  44. * ...
  45. * #endif
  46. *
  47. * This prevents the redefinition of a construct already defined by the kernel.
  48. */
  49. #ifndef _LIBC_COMPAT_H
  50. #define _LIBC_COMPAT_H
  51. /* We have included glibc headers... */
  52. #if defined(__GLIBC__)
  53. /* Coordinate with glibc net/if.h header. */
  54. #if defined(_NET_IF_H) && defined(__USE_MISC)
  55. /* GLIBC headers included first so don't define anything
  56. * that would already be defined. */
  57. #define __UAPI_DEF_IF_IFCONF 0
  58. #define __UAPI_DEF_IF_IFMAP 0
  59. #define __UAPI_DEF_IF_IFNAMSIZ 0
  60. #define __UAPI_DEF_IF_IFREQ 0
  61. /* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */
  62. #define __UAPI_DEF_IF_NET_DEVICE_FLAGS 0
  63. /* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */
  64. #ifndef __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO
  65. #define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1
  66. #endif /* __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO */
  67. #else /* _NET_IF_H */
  68. /* Linux headers included first, and we must define everything
  69. * we need. The expectation is that glibc will check the
  70. * __UAPI_DEF_* defines and adjust appropriately. */
  71. #define __UAPI_DEF_IF_IFCONF 1
  72. #define __UAPI_DEF_IF_IFMAP 1
  73. #define __UAPI_DEF_IF_IFNAMSIZ 1
  74. #define __UAPI_DEF_IF_IFREQ 1
  75. /* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */
  76. #define __UAPI_DEF_IF_NET_DEVICE_FLAGS 1
  77. /* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */
  78. #define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1
  79. #endif /* _NET_IF_H */
  80. /* Coordinate with glibc netinet/in.h header. */
  81. #if defined(_NETINET_IN_H)
  82. /* GLIBC headers included first so don't define anything
  83. * that would already be defined. */
  84. #define __UAPI_DEF_IN_ADDR 0
  85. #define __UAPI_DEF_IN_IPPROTO 0
  86. #define __UAPI_DEF_IN_PKTINFO 0
  87. #define __UAPI_DEF_IP_MREQ 0
  88. #define __UAPI_DEF_SOCKADDR_IN 0
  89. #define __UAPI_DEF_IN_CLASS 0
  90. #define __UAPI_DEF_IN6_ADDR 0
  91. /* The exception is the in6_addr macros which must be defined
  92. * if the glibc code didn't define them. This guard matches
  93. * the guard in glibc/inet/netinet/in.h which defines the
  94. * additional in6_addr macros e.g. s6_addr16, and s6_addr32. */
  95. #if defined(__USE_MISC) || defined (__USE_GNU)
  96. #define __UAPI_DEF_IN6_ADDR_ALT 0
  97. #else
  98. #define __UAPI_DEF_IN6_ADDR_ALT 1
  99. #endif
  100. #define __UAPI_DEF_SOCKADDR_IN6 0
  101. #define __UAPI_DEF_IPV6_MREQ 0
  102. #define __UAPI_DEF_IPPROTO_V6 0
  103. #define __UAPI_DEF_IPV6_OPTIONS 0
  104. #define __UAPI_DEF_IN6_PKTINFO 0
  105. #define __UAPI_DEF_IP6_MTUINFO 0
  106. #else
  107. /* Linux headers included first, and we must define everything
  108. * we need. The expectation is that glibc will check the
  109. * __UAPI_DEF_* defines and adjust appropriately. */
  110. #define __UAPI_DEF_IN_ADDR 1
  111. #define __UAPI_DEF_IN_IPPROTO 1
  112. #define __UAPI_DEF_IN_PKTINFO 1
  113. #define __UAPI_DEF_IP_MREQ 1
  114. #define __UAPI_DEF_SOCKADDR_IN 1
  115. #define __UAPI_DEF_IN_CLASS 1
  116. #define __UAPI_DEF_IN6_ADDR 1
  117. /* We unconditionally define the in6_addr macros and glibc must
  118. * coordinate. */
  119. #define __UAPI_DEF_IN6_ADDR_ALT 1
  120. #define __UAPI_DEF_SOCKADDR_IN6 1
  121. #define __UAPI_DEF_IPV6_MREQ 1
  122. #define __UAPI_DEF_IPPROTO_V6 1
  123. #define __UAPI_DEF_IPV6_OPTIONS 1
  124. #define __UAPI_DEF_IN6_PKTINFO 1
  125. #define __UAPI_DEF_IP6_MTUINFO 1
  126. #endif /* _NETINET_IN_H */
  127. /* Definitions for xattr.h */
  128. #if defined(_SYS_XATTR_H)
  129. #define __UAPI_DEF_XATTR 0
  130. #else
  131. #define __UAPI_DEF_XATTR 1
  132. #endif
  133. /* If we did not see any headers from any supported C libraries,
  134. * or we are being included in the kernel, then define everything
  135. * that we need. Check for previous __UAPI_* definitions to give
  136. * unsupported C libraries a way to opt out of any kernel definition. */
  137. #else /* !defined(__GLIBC__) */
  138. /* Definitions for if.h */
  139. #ifndef __UAPI_DEF_IF_IFCONF
  140. #define __UAPI_DEF_IF_IFCONF 1
  141. #endif
  142. #ifndef __UAPI_DEF_IF_IFMAP
  143. #define __UAPI_DEF_IF_IFMAP 1
  144. #endif
  145. #ifndef __UAPI_DEF_IF_IFNAMSIZ
  146. #define __UAPI_DEF_IF_IFNAMSIZ 1
  147. #endif
  148. #ifndef __UAPI_DEF_IF_IFREQ
  149. #define __UAPI_DEF_IF_IFREQ 1
  150. #endif
  151. /* Everything up to IFF_DYNAMIC, matches net/if.h until glibc 2.23 */
  152. #ifndef __UAPI_DEF_IF_NET_DEVICE_FLAGS
  153. #define __UAPI_DEF_IF_NET_DEVICE_FLAGS 1
  154. #endif
  155. /* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */
  156. #ifndef __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO
  157. #define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1
  158. #endif
  159. /* Definitions for in.h */
  160. #ifndef __UAPI_DEF_IN_ADDR
  161. #define __UAPI_DEF_IN_ADDR 1
  162. #endif
  163. #ifndef __UAPI_DEF_IN_IPPROTO
  164. #define __UAPI_DEF_IN_IPPROTO 1
  165. #endif
  166. #ifndef __UAPI_DEF_IN_PKTINFO
  167. #define __UAPI_DEF_IN_PKTINFO 1
  168. #endif
  169. #ifndef __UAPI_DEF_IP_MREQ
  170. #define __UAPI_DEF_IP_MREQ 1
  171. #endif
  172. #ifndef __UAPI_DEF_SOCKADDR_IN
  173. #define __UAPI_DEF_SOCKADDR_IN 1
  174. #endif
  175. #ifndef __UAPI_DEF_IN_CLASS
  176. #define __UAPI_DEF_IN_CLASS 1
  177. #endif
  178. /* Definitions for in6.h */
  179. #ifndef __UAPI_DEF_IN6_ADDR
  180. #define __UAPI_DEF_IN6_ADDR 1
  181. #endif
  182. #ifndef __UAPI_DEF_IN6_ADDR_ALT
  183. #define __UAPI_DEF_IN6_ADDR_ALT 1
  184. #endif
  185. #ifndef __UAPI_DEF_SOCKADDR_IN6
  186. #define __UAPI_DEF_SOCKADDR_IN6 1
  187. #endif
  188. #ifndef __UAPI_DEF_IPV6_MREQ
  189. #define __UAPI_DEF_IPV6_MREQ 1
  190. #endif
  191. #ifndef __UAPI_DEF_IPPROTO_V6
  192. #define __UAPI_DEF_IPPROTO_V6 1
  193. #endif
  194. #ifndef __UAPI_DEF_IPV6_OPTIONS
  195. #define __UAPI_DEF_IPV6_OPTIONS 1
  196. #endif
  197. #ifndef __UAPI_DEF_IN6_PKTINFO
  198. #define __UAPI_DEF_IN6_PKTINFO 1
  199. #endif
  200. #ifndef __UAPI_DEF_IP6_MTUINFO
  201. #define __UAPI_DEF_IP6_MTUINFO 1
  202. #endif
  203. /* Definitions for xattr.h */
  204. #ifndef __UAPI_DEF_XATTR
  205. #define __UAPI_DEF_XATTR 1
  206. #endif
  207. #endif /* __GLIBC__ */
  208. #endif /* _LIBC_COMPAT_H */