With BTF, users do not need libc headers installed for AF_INET/AF_INET6

Signed-off-by: Bernhard Kaindl <bernhardkaindl7@gmail.com>

tools/tcpaccept.bt

@@ -20,7 +20,13 @@
 #include <linux/socket.h>
 #include <net/sock.h>
 #else
-#include <sys/socket.h>
+/*
+ * With BTF providing types, socket headers are not needed.
+ * We only need to supply the preprocessor defines in this script.
+ * AF_INET/AF_INET6 are part of the stable arch-independent Linux ABI
+ */
+#define AF_INET   2
+#define AF_INET6 10
 #endif
 
 BEGIN

tools/tcpconnect.bt

@@ -23,10 +23,12 @@
 #include <net/sock.h>
 #else
 /*
- * Note: you may need to install the glibc-headers package or other package
- * containing sys/socket.h, which contains the AF_INET and AF_INET6 macros
+ * BTF provides the types, we just need to define AF_INET and AF_INET6.
+ * These are Linux ABI defines, and are not architecture-specific.
+ * With BTF, this allows tcpconnect.bt to work without glibc headers:
  */
-#include <sys/socket.h>
+#define AF_INET   2 /* IPv4 */
+#define AF_INET6 10 /* IPv6 */
 #endif
 
 BEGIN

tools/tcpdrop.bt

@@ -24,7 +24,13 @@
 #include <linux/socket.h>
 #include <net/sock.h>
 #else
-#include <sys/socket.h>
+/*
+ * With BTF providing types, socket headers are not needed.
+ * We only need to supply the preprocessor defines in this script.
+ * AF_INET/AF_INET6 are part of the stable arch-independent Linux ABI
+ */
+#define AF_INET   2
+#define AF_INET6 10
 #endif
 
 BEGIN

tools/tcplife.bt

@@ -19,7 +19,13 @@
 #include <linux/socket.h>
 #include <linux/tcp.h>
 #else
-#include <sys/socket.h>
+/*
+ * With BTF providing types, socket headers are not needed.
+ * We only need to supply the preprocessor defines in this script.
+ * AF_INET/AF_INET6 are part of the stable arch-independent Linux ABI
+ */
+#define AF_INET   2
+#define AF_INET6 10
 #endif
 
 BEGIN

tools/tcpretrans.bt

@@ -21,7 +21,13 @@
 #include <linux/socket.h>
 #include <net/sock.h>
 #else
-#include <sys/socket.h>
+/*
+ * With BTF providing types, socket headers are not needed.
+ * We only need to supply the preprocessor defines in this script.
+ * AF_INET/AF_INET6 are part of the stable arch-independent Linux ABI
+ */
+#define AF_INET   2
+#define AF_INET6 10
 #endif
 
 BEGIN