mod_disk_cache.c

最新apache的源代码

        return DECLINED;
    }

    /* Create and init the cache object */
    h->cache_obj = obj = apr_pcalloc(r->pool, sizeof(cache_object_t));
    obj->vobj = dobj = apr_pcalloc(r->pool, sizeof(disk_cache_object_t));

    info = &(obj->info);
    obj->key = (char *) key;
    dobj->name = (char *) key;
    dobj->datafile = data_file(r->pool, conf, dobj, key);
    dobj->hdrsfile = header_file(r->pool, conf, dobj, key);
    dobj->tempfile = apr_pstrcat(r->pool, conf->cache_root, AP_TEMPFILE, NULL);

    /* Open the data file */
    flags = APR_READ|APR_BINARY;
#ifdef APR_SENDFILE_ENABLED
    flags |= APR_SENDFILE_ENABLED;
#endif
    rc = apr_file_open(&dobj->fd, dobj->datafile, flags, 0, r->pool);
    if (rc != APR_SUCCESS) {
        /* XXX: Log message */
        return DECLINED;
    }

    /* Open the headers file */
    flags = APR_READ|APR_BINARY|APR_BUFFERED;
    rc = apr_file_open(&dobj->hfd, dobj->hdrsfile, flags, 0, r->pool);
    if (rc != APR_SUCCESS) {
        /* XXX: Log message */
        return DECLINED;
    }

    rc = apr_file_info_get(&finfo, APR_FINFO_SIZE, dobj->fd);
    if (rc == APR_SUCCESS) {
        dobj->file_size = finfo.size;
    }

    /* Read the bytes to setup the cache_info fields */
    rc = file_cache_recall_mydata(dobj->hfd, info, dobj, r);
    if (rc != APR_SUCCESS) {
        /* XXX log message */
        return DECLINED;
    }

    /* Initialize the cache_handle callback functions */
    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                 "disk_cache: Recalled cached URL info header %s",  dobj->name);
    return OK;
}

static int remove_entity(cache_handle_t *h)
{
    /* Null out the cache object pointer so next time we start from scratch  */
    h->cache_obj = NULL;
    return OK;
}

static int remove_url(const char *key)
{
    /* XXX: Delete file from cache! */
    return OK;
}

static apr_status_t read_table(cache_handle_t *handle, request_rec *r,
                               apr_table_t *table, apr_file_t *file)
{
    char w[MAX_STRING_LEN];
    char *l;
    int p;
    apr_status_t rv;

    while (1) {

        /* ### What about APR_EOF? */
        rv = apr_file_gets(w, MAX_STRING_LEN - 1, file);
        if (rv != APR_SUCCESS) {
            ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
                          "Premature end of cache headers.");
            return rv;
        }

        /* Delete terminal (CR?)LF */

        p = strlen(w);
        /* Indeed, the host's '\n':
           '\012' for UNIX; '\015' for MacOS; '\025' for OS/390
           -- whatever the script generates.
        */
        if (p > 0 && w[p - 1] == '\n') {
            if (p > 1 && w[p - 2] == CR) {
                w[p - 2] = '\0';
            }
            else {
                w[p - 1] = '\0';
            }
        }

        /* If we've finished reading the headers, break out of the loop. */
        if (w[0] == '\0') {
            break;
        }

#if APR_CHARSET_EBCDIC
        /* Chances are that we received an ASCII header text instead of
         * the expected EBCDIC header lines. Try to auto-detect:
         */
        if (!(l = strchr(w, ':'))) {
            int maybeASCII = 0, maybeEBCDIC = 0;
            unsigned char *cp, native;
            apr_size_t inbytes_left, outbytes_left;

            for (cp = w; *cp != '\0'; ++cp) {
                native = apr_xlate_conv_byte(ap_hdrs_from_ascii, *cp);
                if (apr_isprint(*cp) && !apr_isprint(native))
                    ++maybeEBCDIC;
                if (!apr_isprint(*cp) && apr_isprint(native))
                    ++maybeASCII;
            }
            if (maybeASCII > maybeEBCDIC) {
                ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
                             "CGI Interface Error: Script headers apparently ASCII: (CGI = %s)",
                             r->filename);
                inbytes_left = outbytes_left = cp - w;
                apr_xlate_conv_buffer(ap_hdrs_from_ascii,
                                      w, &inbytes_left, w, &outbytes_left);
            }
        }
#endif /*APR_CHARSET_EBCDIC*/

        /* if we see a bogus header don't ignore it. Shout and scream */
        if (!(l = strchr(w, ':'))) {
            return APR_EGENERAL;
        }

        *l++ = '\0';
        while (*l && apr_isspace(*l)) {
            ++l;
        }

        apr_table_add(table, w, l);
    }

    return APR_SUCCESS;
}

/*
 * Reads headers from a buffer and returns an array of headers.
 * Returns NULL on file error
 * This routine tries to deal with too long lines and continuation lines.
 * @@@: XXX: FIXME: currently the headers are passed thru un-merged.
 * Is that okay, or should they be collapsed where possible?
 */
static apr_status_t recall_headers(cache_handle_t *h, request_rec *r)
{
    disk_cache_object_t *dobj = (disk_cache_object_t *) h->cache_obj->vobj;

    /* This case should not happen... */
    if (!dobj->hfd) {
        /* XXX log message */
        return APR_NOTFOUND;
    }

    h->req_hdrs = apr_table_make(r->pool, 20);
    h->resp_hdrs = apr_table_make(r->pool, 20);
    h->resp_err_hdrs = apr_table_make(r->pool, 20);

    /* Call routine to read the header lines/status line */
    read_table(h, r, h->resp_hdrs, dobj->hfd);
    read_table(h, r, h->req_hdrs, dobj->hfd);

    apr_file_close(dobj->hfd);

    h->status = dobj->disk_info.status;
    h->content_type = apr_table_get(h->resp_hdrs, "Content-Type");

    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                 "disk_cache: Recalled headers for URL %s",  dobj->name);
    return APR_SUCCESS;
}

static apr_status_t recall_body(cache_handle_t *h, apr_pool_t *p, apr_bucket_brigade *bb)
{
    apr_bucket *e;
    disk_cache_object_t *dobj = (disk_cache_object_t*) h->cache_obj->vobj;

    e = apr_bucket_file_create(dobj->fd, 0, (apr_size_t) dobj->file_size, p,
                               bb->bucket_alloc);
    APR_BRIGADE_INSERT_HEAD(bb, e);
    e = apr_bucket_eos_create(bb->bucket_alloc);
    APR_BRIGADE_INSERT_TAIL(bb, e);

    return APR_SUCCESS;
}

static apr_status_t store_table(apr_file_t *fd, apr_table_t *table)
{
    int i;
    apr_status_t rv;
    struct iovec iov[4];
    apr_size_t amt;
    apr_table_entry_t *elts;

    elts = (apr_table_entry_t *) apr_table_elts(table)->elts;
    for (i = 0; i < apr_table_elts(table)->nelts; ++i) {
        if (elts[i].key != NULL) {
            iov[0].iov_base = elts[i].key;
            iov[0].iov_len = strlen(elts[i].key);
            iov[1].iov_base = ": ";
            iov[1].iov_len = sizeof(": ") - 1;
            iov[2].iov_base = elts[i].val;
            iov[2].iov_len = strlen(elts[i].val);
            iov[3].iov_base = CRLF;
            iov[3].iov_len = sizeof(CRLF) - 1;

            rv = apr_file_writev(fd, (const struct iovec *) &iov, 4,
                                 &amt);
            if (rv != APR_SUCCESS) {
                return rv;
            }
        }
    }
    iov[0].iov_base = CRLF;
    iov[0].iov_len = sizeof(CRLF) - 1;
    rv = apr_file_writev(fd, (const struct iovec *) &iov, 1,
                         &amt);
    return rv;
}

static apr_status_t store_headers(cache_handle_t *h, request_rec *r, cache_info *info)
{
    disk_cache_conf *conf = ap_get_module_config(r->server->module_config,
                                                 &disk_cache_module);
    apr_status_t rv;
    apr_size_t amt;
    disk_cache_object_t *dobj = (disk_cache_object_t*) h->cache_obj->vobj;

    if (!dobj->hfd)  {
        disk_cache_info_t disk_info;
        struct iovec iov[2];

        /* This is flaky... we need to manage the cache_info differently */
        h->cache_obj->info = *info;

        /* Remove old file with the same name. If remove fails, then
         * perhaps we need to create the directory tree where we are
         * about to write the new headers file.
         */
        rv = apr_file_remove(dobj->hdrsfile, r->pool);
        if (rv != APR_SUCCESS) {
            mkdir_structure(conf, dobj->hdrsfile, r->pool);
        }

        rv = apr_file_open(&dobj->hfd, dobj->hdrsfile,
                           APR_WRITE | APR_CREATE | APR_EXCL,
                           APR_OS_DEFAULT, r->pool);
        if (rv != APR_SUCCESS) {
            return rv;
        }
        dobj->name = h->cache_obj->key;

        disk_info.format = DISK_FORMAT_VERSION;
        disk_info.date = info->date;
        disk_info.expire = info->expire;
        disk_info.entity_version = dobj->disk_info.entity_version++;
        disk_info.request_time = info->request_time;
        disk_info.response_time = info->response_time;
        disk_info.status = info->status;

        disk_info.name_len = strlen(dobj->name);

        iov[0].iov_base = (void*)&disk_info;
        iov[0].iov_len = sizeof(disk_cache_info_t);
        iov[1].iov_base = dobj->name;
        iov[1].iov_len = disk_info.name_len;

        rv = apr_file_writev(dobj->hfd, (const struct iovec *) &iov, 2, &amt);
        if (rv != APR_SUCCESS) {
            return rv;
        }

        if (r->headers_out) {
            apr_table_t *headers_out;

            headers_out = ap_cache_cacheable_hdrs_out(r->pool, r->headers_out,
                                                      r->server);

            if (!apr_table_get(headers_out, "Content-Type") &&
                r->content_type) {
                apr_table_setn(headers_out, "Content-Type",
                               ap_make_content_type(r, r->content_type));
            }

            rv = store_table(dobj->hfd, headers_out);
            if (rv != APR_SUCCESS) {
                return rv;
            }

        }

        /* Parse the vary header and dump those fields from the headers_in. */
        /* Make call to the same thing cache_select_url calls to crack Vary. */
        /* @@@ Some day, not today. */
        if (r->headers_in) {
            apr_table_t *headers_in;

            headers_in = ap_cache_cacheable_hdrs_out(r->pool, r->headers_in,
                                                     r->server);
            rv = store_table(dobj->hfd, headers_in);
            if (rv != APR_SUCCESS) {
                return rv;
            }
        }
        apr_file_close(dobj->hfd); /* flush and close */
    }
    else {
        /* XXX log message */
    }

    ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
                 "disk_cache: Stored headers for URL %s",  dobj->name);
    return APR_SUCCESS;