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#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/uio.h>
#include "econpacket.h"
#include "econproto.h"
static void
init_iov(struct econ_packet *pkt)
{
pkt->iov[0].iov_base = &pkt->hdr;
pkt->iov[0].iov_len = sizeof pkt->hdr;
pkt->iov[1].iov_base = &pkt->cmd;
pkt->iov[1].iov_len = sizeof pkt->cmd;
pkt->iov[2].iov_base = &pkt->rec;
pkt->iov[2].iov_len = sizeof pkt->rec;
}
static void
init_header(struct econ_header *ehdr, int cmd)
{
memset(ehdr, 0, sizeof *ehdr);
strncpy(ehdr->magicnum, ECON_MAGIC_NUMBER, ECON_MAGICNUM_SIZE);
strncpy(ehdr->version, ECON_PROTO_VERSION, ECON_PROTOVER_MAXLEN);
ehdr->datasize = 0;
ehdr->commandID = cmd;
}
void
epkt_init(struct econ_packet *pkt, int cmd)
{
init_iov(pkt);
memset(&pkt->rec, 0, sizeof pkt->rec);
memset(&pkt->cmd, 0, sizeof pkt->cmd);
init_header(&pkt->hdr, cmd);
}
int
epkt_send(int fd, struct econ_packet *pkt)
{
int i = 1;
if (pkt->hdr.datasize > 0) {
i++;
if (pkt->cmd.recordCount == 1)
i++;
}
return writev(fd, pkt->iov, i);
}
int
epkt_read(int fd, struct econ_packet *pkt)
{
union { ssize_t s; size_t u; } len;
init_iov(pkt);
len.s = readv(fd, pkt->iov, 3);
if (len.s < 0)
return -1;
if (len.u < sizeof(struct econ_header)) {
fprintf(stderr, "epkt_read: error: incomplete header\n");
return -1;
}
if (len.u < sizeof(struct econ_header) + pkt->hdr.datasize) {
fprintf(stderr, "packet has invalid datasize\n");
return -1;
}
if (pkt->hdr.datasize > 0) {
if (pkt->hdr.datasize < sizeof(struct econ_command)) {
fprintf(stderr,
"epkt_read: error: command to short\n");
return -1;
}
/* Keepalive is an irregular if datasize > 0:
* the regular field recordCount is 1,
* without actually having one. */
if (pkt->hdr.commandID == E_CMD_KEEPALIVE)
return 0;
if (pkt->cmd.recordCount > 0) {
if (pkt->cmd.recordCount > 1) {
fprintf(stderr, "epkt_read:"
" did not expect a packet with more"
" that one record: %d, datasize: %d.\n",
pkt->cmd.recordCount, pkt->hdr.datasize);
return -1;
}
if (pkt->hdr.datasize != (sizeof (struct econ_command) +
sizeof (struct econ_record))) {
fprintf(stderr, "epkt_read: datasize incorrect, cmd: %d\n",
pkt->hdr.commandID);
return -1;
}
}
}
return 0;
}
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