From 557b4bf26ed7f5193d2d9f78809d5254ef4d8587 Mon Sep 17 00:00:00 2001 From: c8ef Date: Sat, 15 Nov 2025 22:52:02 +0800 Subject: [PATCH 1/2] [libc] Add IN6_IS_ADDR_{LINK, SITE}LOCAL --- .../llvm-libc-macros/netinet-in-macros.h | 8 +++++ libc/test/include/netinet_in_test.cpp | 31 +++++++++---------- 2 files changed, 23 insertions(+), 16 deletions(-) diff --git a/libc/include/llvm-libc-macros/netinet-in-macros.h b/libc/include/llvm-libc-macros/netinet-in-macros.h index 2011c34e288cd..c0d8c19045154 100644 --- a/libc/include/llvm-libc-macros/netinet-in-macros.h +++ b/libc/include/llvm-libc-macros/netinet-in-macros.h @@ -33,4 +33,12 @@ #define INET_ADDRSTRLEN 16 #define INET6_ADDRSTRLEN 46 +#define IN6_IS_ADDR_LINKLOCAL(a) \ + ((__LLVM_LIBC_CAST(reinterpret_cast, uint8_t *, a)[0]) == 0xfe && \ + (__LLVM_LIBC_CAST(reinterpret_cast, uint8_t *, a)[1] & 0xc0) == 0x80) + +#define IN6_IS_ADDR_SITELOCAL(a) \ + ((__LLVM_LIBC_CAST(reinterpret_cast, uint8_t *, a)[0]) == 0xfe && \ + (__LLVM_LIBC_CAST(reinterpret_cast, uint8_t *, a)[1] & 0xc0) == 0xc0) + #endif // LLVM_LIBC_MACROS_NETINET_IN_MACROS_H diff --git a/libc/test/include/netinet_in_test.cpp b/libc/test/include/netinet_in_test.cpp index 714892f511b1c..6937262f92e90 100644 --- a/libc/test/include/netinet_in_test.cpp +++ b/libc/test/include/netinet_in_test.cpp @@ -9,21 +9,20 @@ #include "include/llvm-libc-macros/netinet-in-macros.h" #include "test/UnitTest/Test.h" -TEST(LlvmLibcNetinetInTest, IPPROTOMacro) { - EXPECT_EQ(IPPROTO_IP, 0); - EXPECT_EQ(IPPROTO_ICMP, 1); - EXPECT_EQ(IPPROTO_TCP, 6); - EXPECT_EQ(IPPROTO_UDP, 17); - EXPECT_EQ(IPPROTO_IPV6, 41); - EXPECT_EQ(IPPROTO_RAW, 255); -} +TEST(LlvmLibcNetinetInTest, IN6Macro) { + char buff[16] = {}; + + buff[0] = 0xfe; + buff[1] = 0x80; + EXPECT_TRUE(IN6_IS_ADDR_LINKLOCAL(buff)); + buff[0] = 0xff; + buff[1] = 0x80; + EXPECT_FALSE(IN6_IS_ADDR_LINKLOCAL(buff)); -TEST(LlvmLibcNetinetInTest, IPV6Macro) { - EXPECT_EQ(IPV6_UNICAST_HOPS, 16); - EXPECT_EQ(IPV6_MULTICAST_IF, 17); - EXPECT_EQ(IPV6_MULTICAST_HOPS, 18); - EXPECT_EQ(IPV6_MULTICAST_LOOP, 19); - EXPECT_EQ(IPV6_JOIN_GROUP, 20); - EXPECT_EQ(IPV6_LEAVE_GROUP, 21); - EXPECT_EQ(IPV6_V6ONLY, 26); + buff[0] = 0xfe; + buff[1] = 0xc0; + EXPECT_TRUE(IN6_IS_ADDR_SITELOCAL(buff)); + buff[0] = 0xff; + buff[1] = 0x80; + EXPECT_FALSE(IN6_IS_ADDR_SITELOCAL(buff)); } From f1a3ad72c92ecb0527eaf8b70be81fd0602b5946 Mon Sep 17 00:00:00 2001 From: c8ef Date: Thu, 11 Dec 2025 01:08:35 +0800 Subject: [PATCH 2/2] add comments --- libc/include/llvm-libc-macros/netinet-in-macros.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/libc/include/llvm-libc-macros/netinet-in-macros.h b/libc/include/llvm-libc-macros/netinet-in-macros.h index c0d8c19045154..599d31edca019 100644 --- a/libc/include/llvm-libc-macros/netinet-in-macros.h +++ b/libc/include/llvm-libc-macros/netinet-in-macros.h @@ -33,6 +33,10 @@ #define INET_ADDRSTRLEN 16 #define INET6_ADDRSTRLEN 46 +// The following macros test for special IPv6 addresses. Each macro is of type +// int and takes a single argument of type const struct in6_addr *: +// https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/netinet_in.h.html + #define IN6_IS_ADDR_LINKLOCAL(a) \ ((__LLVM_LIBC_CAST(reinterpret_cast, uint8_t *, a)[0]) == 0xfe && \ (__LLVM_LIBC_CAST(reinterpret_cast, uint8_t *, a)[1] & 0xc0) == 0x80)