apr_buckets_pipe.c

Apache V2.0.15 Alpha For Linuxhttpd-2_0_15-alpha.tar.Z

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#include "apr_buckets.h"
#include <stdlib.h>

static apr_status_t pipe_read(apr_bucket *a, const char **str,
			      apr_size_t *len, apr_read_type_e block)
{
    apr_file_t *p = a->data;
    char *buf;
    apr_status_t rv;
    apr_interval_time_t timeout;

    if (block == APR_NONBLOCK_READ) {
        apr_file_pipe_timeout_get(p, &timeout);
        apr_file_pipe_timeout_set(p, 0);
    }

    *str = NULL;
    *len = APR_BUCKET_BUFF_SIZE;
    buf = malloc(*len); /* XXX: check for failure? */

    rv = apr_file_read(p, buf, len);

    if (block == APR_NONBLOCK_READ) {
        apr_file_pipe_timeout_set(p, timeout);
    }

    if (rv != APR_SUCCESS && rv != APR_EOF) {
	free(buf);
        return rv;
    }
    /*
     * If there's more to read we have to keep the rest of the pipe
     * for later.  Otherwise, we'll close the pipe.
     * XXX: Note that more complicated bucket types that 
     * refer to data not in memory and must therefore have a read()
     * function similar to this one should be wary of copying this
     * code because if they have a destroy function they probably
     * want to migrate the bucket's subordinate structure from the
     * old bucket to a raw new one and adjust it as appropriate,
     * rather than destroying the old one and creating a completely
     * new bucket.
     */
    if (*len > 0) {
        apr_bucket_heap *h;
        /* Change the current bucket to refer to what we read */
        /* XXX: check for failure? */
        a = apr_bucket_heap_make(a, buf, *len, 0, NULL);
        h = a->data;
        h->alloc_len = APR_BUCKET_BUFF_SIZE; /* note the real buffer size */
        *str = buf;
        APR_BUCKET_INSERT_AFTER(a, apr_bucket_pipe_create(p));
    }
    else {
        free(buf);
        a = apr_bucket_immortal_make(a, "", 0);
        *str = a->data;
        if (rv == APR_EOF) {
            apr_file_close(p);
            if (block == APR_NONBLOCK_READ) {
                /* XXX: this is bogus, should return APR_SUCCESS */
                return APR_EOF;
            }
        }
    }
    return APR_SUCCESS;
}

APU_DECLARE(apr_bucket *) apr_bucket_pipe_make(apr_bucket *b, apr_file_t *p)
{
    /*
     * A pipe is closed when the end is reached in pipe_read().  If the
     * pipe isn't read to the end (e.g., error path), the pipe will be
     * closed when its pool goes away.
     *
     * Note that typically the pipe is allocated from the request pool
     * so it will disappear when the request is finished. However the
     * core filter may decide to set aside the tail end of a CGI
     * response if the connection is pipelined. This turns out not to
     * be a problem because the core will have read to the end of the
     * stream so the bucket(s) that it sets aside will be the heap
     * buckets created by pipe_read() above.
     */
    b->type     = &apr_bucket_type_pipe;
    b->length   = -1;
    b->start    = -1;
    b->data     = p;

    return b;
}

APU_DECLARE(apr_bucket *) apr_bucket_pipe_create(apr_file_t *p)
{
    apr_bucket_do_create(apr_bucket_pipe_make(b, p));
}

APU_DECLARE_DATA const apr_bucket_type_t apr_bucket_type_pipe = {
    "PIPE", 5,
    apr_bucket_destroy_notimpl,
    pipe_read,
    apr_bucket_setaside_notimpl,
    apr_bucket_split_notimpl,
    apr_bucket_copy_notimpl
};