pcap: add pcap_iov()

Introduce a new function pcap_iov() to capture packet desribed by an IO
vector.

Update pcap_frame() to manage iovcnt > 1.

Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-ID: <20240303135114.1023026-2-lvivier@redhat.com>
[dwg: Fixed trivial cppcheck regressions]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
Laurent Vivier 2024-03-06 16:58:30 +11:00 committed by Stefano Brivio
parent 3b9098aa49
commit 94502fa15e
3 changed files with 24 additions and 5 deletions

1
iov.c
View file

@ -146,7 +146,6 @@ size_t iov_to_buf(const struct iovec *iov, size_t iov_cnt,
*
* Returns: The total size in bytes.
*/
/* cppcheck-suppress unusedFunction */
size_t iov_size(const struct iovec *iov, size_t iov_cnt)
{
unsigned int i;

27
pcap.c
View file

@ -32,6 +32,7 @@
#include "passt.h"
#include "log.h"
#include "pcap.h"
#include "iov.h"
#define PCAP_VERSION_MINOR 4
@ -78,7 +79,7 @@ struct pcap_pkthdr {
static void pcap_frame(const struct iovec *iov, size_t iovcnt,
size_t offset, const struct timeval *tv)
{
size_t len = iov->iov_len - offset;
size_t len = iov_size(iov, iovcnt) - offset;
struct pcap_pkthdr h = {
.tv_sec = tv->tv_sec,
.tv_usec = tv->tv_usec,
@ -87,10 +88,8 @@ static void pcap_frame(const struct iovec *iov, size_t iovcnt,
};
struct iovec hiov = { &h, sizeof(h) };
(void)iovcnt;
if (write_remainder(pcap_fd, &hiov, 1, 0) < 0 ||
write_remainder(pcap_fd, iov, 1, offset) < 0) {
write_remainder(pcap_fd, iov, iovcnt, offset) < 0) {
debug("Cannot log packet, length %zu: %s",
len, strerror(errno));
}
@ -135,6 +134,26 @@ void pcap_multiple(const struct iovec *iov, size_t frame_parts, unsigned int n,
pcap_frame(iov + i * frame_parts, frame_parts, offset, &tv);
}
/*
* pcap_iov - Write packet data described by an I/O vector
* to a pcap file descriptor.
*
* @iov: Pointer to the array of struct iovec describing the I/O vector
* containing packet data to write, including L2 header
* @iovcnt: Number of buffers (@iov entries)
*/
/* cppcheck-suppress unusedFunction */
void pcap_iov(const struct iovec *iov, size_t iovcnt)
{
struct timeval tv;
if (pcap_fd == -1)
return;
gettimeofday(&tv, NULL);
pcap_frame(iov, iovcnt, 0, &tv);
}
/**
* pcap_init() - Initialise pcap file
* @c: Execution context

1
pcap.h
View file

@ -9,6 +9,7 @@
void pcap(const char *pkt, size_t len);
void pcap_multiple(const struct iovec *iov, size_t frame_parts, unsigned int n,
size_t offset);
void pcap_iov(const struct iovec *iov, size_t iovcnt);
void pcap_init(struct ctx *c);
#endif /* PCAP_H */