path: root/include
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authorRich Felker <>2014-02-05 16:55:30 -0500
committerRich Felker <>2014-02-05 16:55:30 -0500
commitfdaaa68d827430caa930e4c966fa8d8a9f8f64c4 (patch)
tree204e1429ecf0dfe0d88cc99b614f4baf564106ad /include
parentad87c2eecf70c6f2852a4908b04a6329cbebaf7d (diff)
add support for BSD struct tcphdr in netinet/tcp.h
there are two versions of this structure: the BSD version and the GNU version. previously only the GNU version was supported. the only way to support both simultaneously is with an anonymous union, which was a nonstandard extension prior to C11, so some effort is made to avoid breakage with compilers which do not support anonymous unions. this commit is based on a patch by Timo Teräs, but with some changes. in particular, the GNU version of the structure is not exposed unless _GNU_SOURCE is defined; this both avoids namespace pollution and dependency on anonymous unions in the default feature profile.
Diffstat (limited to 'include')
1 files changed, 41 insertions, 4 deletions
diff --git a/include/netinet/tcp.h b/include/netinet/tcp.h
index 5639b89a..9be2b940 100644
--- a/include/netinet/tcp.h
+++ b/include/netinet/tcp.h
@@ -44,12 +44,24 @@
#define SOL_TCP 6
#include <sys/types.h>
#include <sys/socket.h>
+#include <endian.h>
+typedef u_int32_t tcp_seq;
+#define TH_FIN 0x01
+#define TH_SYN 0x02
+#define TH_RST 0x04
+#define TH_PUSH 0x08
+#define TH_ACK 0x10
+#define TH_URG 0x20
+struct tcphdr {
#ifdef _GNU_SOURCE
-#include <endian.h>
-struct tcphdr
+#ifdef __GNUC__
+ __extension__
+ union { struct {
u_int16_t source;
u_int16_t dest;
u_int32_t seq;
@@ -78,8 +90,33 @@ struct tcphdr
u_int16_t window;
u_int16_t check;
u_int16_t urg_ptr;
+ }; struct {
+ u_int16_t th_sport;
+ u_int16_t th_dport;
+ u_int32_t th_seq;
+ u_int32_t th_ack;
+ u_int8_t th_x2:4;
+ u_int8_t th_off:4;
+ u_int8_t th_off:4;
+ u_int8_t th_x2:4;
+ u_int8_t th_flags;
+ u_int16_t th_win;
+ u_int16_t th_sum;
+ u_int16_t th_urp;
+#ifdef _GNU_SOURCE
+ }; };
+#ifdef _GNU_SOURCE
#define TCPI_OPT_SACK 2