fluffy/pmerge.c

128 lines
2.6 KiB
C

#include <stdio.h>
#include <stdint.h>
#include <sysexits.h>
#include "pcap.h"
struct input_file {
int active;
struct pcap_file p;
struct pcap_pkthdr next;
};
int
usage(int ret)
{
printf("Usage: pmerge FILE ...\n");
printf("\n");
printf("Merges pcap files, outputting time-ordered pcap stream\n");
return ret;
}
int
read_next(struct input_file *file)
{
if (! file->active) return -1;
if (-1 == pcap_read_pkthdr(&file->p, &file->next)) {
pcap_close(&file->p);
file->active = 0;
file->next.ts.tv_sec = 0xffffffff;
file->next.ts.tv_usec = 0xffffffff;
return -1;
}
return 0;
}
int
main(int argc, char *argv[])
{
struct input_file files[argc-1];
int nfiles = 0;
int nopen;
int i;
struct pcap_file out;
if (1 == argc) return usage(0);
/* Open input files */
for (i = 0; i < argc-1; i += 1) {
char *fn = argv[i+1];
struct input_file *cur = &files[nfiles];
FILE *f;
if ('-' == fn[0]) return usage(0);
f = fopen(fn, "rb");
if (NULL == f) {
perror(fn);
return EX_NOINPUT;
}
if (-1 == pcap_open_in(&cur->p, f)) {
fprintf(stderr, "%s: unable to process\n", fn);
return EX_IOERR;
}
cur->active = 1;
if (0 == read_next(cur)) {
nfiles += 1;
}
}
if (-1 == pcap_open_out(&out, stdout)) {
perror("writing header");
return EX_IOERR;
}
nopen = nfiles;
while (nopen) {
struct input_file *cur = &files[0];
char frame[MAXFRAME];
size_t len;
/* Find next oldest frame */
for (i = 0; i < nfiles; i += 1) {
if (files[i].active &&
((files[i].next.ts.tv_sec < cur->next.ts.tv_sec) ||
((files[i].next.ts.tv_sec == cur->next.ts.tv_sec) &&
(files[i].next.ts.tv_usec < cur->next.ts.tv_usec)))) {
cur = &files[i];
}
}
/* Make sure it'll fit */
if (cur->next.caplen > sizeof(frame)) {
fprintf(stderr, "error: huge frame (size %u)\n", len);
return EX_SOFTWARE;
}
/* Read it */
len = fread(frame, 1, cur->next.caplen, cur->p.f);
if (len < cur->next.caplen) {
/* Short read */
cur->next.caplen = len;
pcap_close(&cur->p);
cur->active = 0;
}
/* Write header + frame */
if (len) {
if (1 != fwrite(&cur->next, sizeof(cur->next), 1, stdout)) {
perror("error");
return EX_IOERR;
}
if (len != fwrite(frame, 1, len, stdout)) {
perror("error");
return EX_IOERR;
}
}
if (-1 == read_next(cur)) {
nopen -= 1;
}
}
return 0;
}