src/lib/ostream-hash.c

/* Copyright (c) 2013-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "hash-method.h"
#include "ostream-private.h"
#include "ostream-hash.h"

struct hash_ostream {
    struct ostream_private ostream;
    const struct hash_method *method;
    void *hash_context;
};

static ssize_t
o_stream_hash_sendv(struct ostream_private *stream,
            const struct const_iovec *iov, unsigned int iov_count)
{
    struct hash_ostream *hstream = (struct hash_ostream *)stream;
    unsigned int i;
    size_t bytes_left, block_len;
    ssize_t ret;

    if ((ret = o_stream_sendv(stream->parent, iov, iov_count)) < 0) {
        o_stream_copy_error_from_parent(stream);
        return -1;
    }
    if (ret > 0) {
        bytes_left = ret;
        for (i = 0; i < iov_count && bytes_left > 0; i++) {
            block_len = iov[i].iov_len <= bytes_left ?
                iov[i].iov_len : bytes_left;
            hstream->method->loop(hstream->hash_context,
                          iov[i].iov_base, block_len);
            bytes_left -= block_len;
        }
    }

    stream->ostream.offset += ret;
    return ret;
}

struct ostream *
o_stream_create_hash(struct ostream *output, const struct hash_method *method,
             void *hash_context)
{
    struct hash_ostream *hstream;

    hstream = i_new(struct hash_ostream, 1);
    hstream->ostream.sendv = o_stream_hash_sendv;
    hstream->method = method;
    hstream->hash_context = hash_context;

    return o_stream_create(&hstream->ostream, output,
                   o_stream_get_fd(output));
}