source: rtems/cpukit/shttpd/io_file.c @ 484cd8d

/*
 * Copyright (c) 2004-2005 Sergey Lyubka <valenok@gmail.com>
 * All rights reserved
 *
 * "THE BEER-WARE LICENSE" (Revision 42):
 * Sergey Lyubka wrote this file.  As long as you retain this notice you
 * can do whatever you want with this stuff. If we meet some day, and you think
 * this stuff is worth it, you can buy me a beer in return.
 */

#include "defs.h"

static int
write_file(struct stream *stream, const void *buf, size_t len)
{
        struct stat     st;
        struct stream   *rem = &stream->conn->rem;
        int             n, fd = stream->chan.fd;

        assert(fd != -1);
        n = write(fd, buf, len);

        DBG(("put_file(%p, %d): %d bytes", (void *) stream, len, n));

        if (n <= 0 || (rem->io.total >= (big_int_t) rem->headers_len)) {
                (void) fstat(fd, &st);
                stream->io.head = stream->headers_len =
                    my_snprintf(stream->io.buf,
                    stream->io.size, "HTTP/1.1 %d OK\r\n"
                    "Content-Length: %lu\r\nConnection: close\r\n\r\n",
                    stream->conn->status, st.st_size);
                stop_stream(stream);
        }

        return (n);
}

static int
read_file(struct stream *stream, void *buf, size_t len)
{
#ifdef USE_SENDFILE
        struct  iovec   vec;
        struct  sf_hdtr hd = {&vec, 1, NULL, 0}, *hdp = &hd;
        int             sock, fd, n;
        size_t          nbytes;
        off_t           sent;

        sock = stream->conn->rem.chan.sock;
        fd = stream->chan.fd;

        /* If this is the first call for this file, send the headers */
        vec.iov_base = stream->io.buf;
        vec.iov_len = stream->headers_len;
        if (stream->io.total > 0)
                hdp = NULL;

        nbytes = stream->content_len - stream->io.total;
        n = sendfile(fd, sock, lseek(fd, 0, SEEK_CUR), nbytes, hdp, &sent, 0);

        if (n == -1 && ERRNO != EAGAIN) {
                stream->flags &= ~FLAG_DONT_CLOSE;
                return (n);
        }

        stream->conn->ctx->out += sent;

        /* If we have sent the HTTP headers in this turn, clear them off */
        if (stream->io.total == 0) {
                assert(sent >= stream->headers_len);
                sent -= stream->headers_len;
                io_clear(&stream->io);
        }

        (void) lseek(fd, sent, SEEK_CUR);
        stream->io.total += sent;
        stream->flags |= FLAG_DONT_CLOSE;

        return (0);
#endif /* USE_SENDFILE */

        assert(stream->chan.fd != -1);
        return (read(stream->chan.fd, buf, len));
}

static void
close_file(struct stream *stream)
{
        assert(stream->chan.fd != -1);
        (void) close(stream->chan.fd);
}

void
get_file(struct conn *c, struct stat *stp)
{
        char            date[64], lm[64], etag[64], range[64] = "";
        size_t          n, status = 200;
        unsigned long   r1, r2;
        const char      *fmt = "%a, %d %b %Y %H:%M:%S GMT", *msg = "OK";
        big_int_t       cl; /* Content-Length */

        if (c->mime_type == NULL)
                c->mime_type = get_mime_type(c->ctx, c->uri, strlen(c->uri));
        cl = (big_int_t) stp->st_size;

        /* If Range: header specified, act accordingly */
        if (c->ch.range.v_vec.len > 0 &&
            (n = sscanf(c->ch.range.v_vec.ptr,"bytes=%lu-%lu",&r1, &r2)) > 0) {
                status = 206;
                (void) lseek(c->loc.chan.fd, r1, SEEK_SET);
                cl = n == 2 ? r2 - r1 + 1: cl - r1;
                (void) my_snprintf(range, sizeof(range),
                    "Content-Range: bytes %lu-%lu/%lu\r\n",
                    r1, r1 + cl - 1, (unsigned long) stp->st_size);
                msg = "Partial Content";
        }

        /* Prepare Etag, Date, Last-Modified headers */
        (void) strftime(date, sizeof(date), fmt, localtime(&current_time));
        (void) strftime(lm, sizeof(lm), fmt, localtime(&stp->st_mtime));
        (void) my_snprintf(etag, sizeof(etag), "%lx.%lx",
            (unsigned long) stp->st_mtime, (unsigned long) stp->st_size);

        /*
         * We do not do io_inc_head here, because it will increase 'total'
         * member in io. We want 'total' to be equal to the content size,
         * and exclude the headers length from it.
         */
        c->loc.io.head = c->loc.headers_len = my_snprintf(c->loc.io.buf,
            c->loc.io.size,
            "HTTP/1.1 %d %s\r\n"
            "Date: %s\r\n"
            "Last-Modified: %s\r\n"
            "Etag: \"%s\"\r\n"
            "Content-Type: %s\r\n"
            "Content-Length: %lu\r\n"
            "Connection: close\r\n"
            "%s\r\n",
            status, msg, date, lm, etag, c->mime_type, cl, range);

        c->status = status;
        c->loc.content_len = cl;
        c->loc.io_class = &io_file;
        c->loc.flags |= FLAG_R | FLAG_ALWAYS_READY;

        if (c->method == METHOD_HEAD)
                stop_stream(&c->loc);
}

const struct io_class   io_file =  {
        "file",
        read_file,
        write_file,
        close_file
};