xref: /freebsd/contrib/libpcap/pcap-common.h (revision 3bdf775801b218aa5a89564839405b122f4b233e)
1 
2 /*
3  * We use the "receiver-makes-right" approach to byte order,
4  * because time is at a premium when we are writing the file.
5  * In other words, the pcap_file_header and pcap_pkthdr,
6  * records are written in host byte order.
7  * Note that the bytes of packet data are written out in the order in
8  * which they were received, so multi-byte fields in packets are not
9  * written in host byte order, they're written in whatever order the
10  * sending machine put them in.
11  *
12  * ntoh[ls] aren't sufficient because we might need to swap on a big-endian
13  * machine (if the file was written in little-end order).
14  */
15 #define	SWAPLONG(y) \
16 ((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
17 #define	SWAPSHORT(y) \
18 	( (((y)&0xff)<<8) | ((u_short)((y)&0xff00)>>8) )
19 
20 extern int dlt_to_linktype(int dlt);
21 
22 extern int linktype_to_dlt(int linktype);
23 
24 extern void swap_linux_usb_header(const struct pcap_pkthdr *hdr, u_char *buf,
25     int header_len_64_bytes);
26