hexagram/src/pcapng.c

#include <stdint.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>

#include <hexagram/pcapng.h>

ssize_t hexagram_pcapng_stream_read(fd, handler, error)
    int fd;
    hexagram_pcapng_block_handler *handler;
    int *error;
{
    hexagram_pcapng_header header;
    hexagram_pcapng_footer footer;
    ssize_t total = 0;

    while (1) {
        ssize_t readlen;

        if ((readlen = read(fd, &header, sizeof(header))) < 0) {
            *error = HEXAGRAM_PCAPNG_ERROR_IO;

            goto error_io;
        } else if (readlen == 0) {
            goto done;
        } else if (readlen < sizeof(header)) {
            *error = HEXAGRAM_PCAPNG_ERROR_TRUNCATED;

            goto error_io;
        }

        total += readlen;

        if (handler(fd, header.type, header.length - sizeof(header) - sizeof(footer)) < 0) {
            *error = HEXAGRAM_PCAPNG_ERROR_HANDLER;

            goto error_io;
        }

        if ((readlen = read(fd, &footer, sizeof(footer))) < 0) {
            *error = HEXAGRAM_PCAPNG_ERROR_IO;

            goto error_io;
        } else if (readlen == 0) {
            goto done;
        } else if (readlen < sizeof(footer)) {
            *error = HEXAGRAM_PCAPNG_ERROR_TRUNCATED;

            goto error_io;
        }

        if (footer.length != header.length) {
            *error = HEXAGRAM_PCAPNG_ERROR_FORMAT;

            goto error_io;
        }
    }

    *error = HEXAGRAM_PCAPNG_ERROR_OK;

done:
    return total;

error_io:
    return -1;
}