ngx_http_special_response.c

Nginx是一个高性能的HTTP和反向代理服务器

            case NGX_HTTP_BAD_REQUEST:
            case NGX_HTTP_TO_HTTPS:
            case NGX_HTTPS_CERT_ERROR:
            case NGX_HTTPS_NO_CERT:
                r->lingering_close = 0;
        }
    }

    r->headers_out.content_type.len = 0;

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    if (!r->error_page && clcf->error_pages) {

        if (clcf->recursive_error_pages == 0) {
            r->error_page = 1;
        }

        err_page = clcf->error_pages->elts;

        for (i = 0; i < clcf->error_pages->nelts; i++) {
            if (err_page[i].status == error) {
                return ngx_http_send_error_page(r, &err_page[i]);
            }
        }
    }

    if (clcf->msie_refresh
        && r->headers_in.msie
        && (error == NGX_HTTP_MOVED_PERMANENTLY
            || error == NGX_HTTP_MOVED_TEMPORARILY))
    {
        return ngx_http_send_refresh(r);
    }

    if (error == NGX_HTTP_CREATED) {
        /* 201 */
        err = 0;
        r->header_only = 1;

    } else if (error == NGX_HTTP_NO_CONTENT) {
        /* 204 */
        err = 0;

    } else if (error < NGX_HTTP_BAD_REQUEST) {
        /* 3XX */
        err = error - NGX_HTTP_MOVED_PERMANENTLY + NGX_HTTP_LEVEL_200;

    } else if (error < NGX_HTTP_OWN_CODES) {
        /* 4XX */
        err = error - NGX_HTTP_BAD_REQUEST + NGX_HTTP_LEVEL_200
                                           + NGX_HTTP_LEVEL_300;

    } else {
        /* 49X, 5XX */
        err = error - NGX_HTTP_OWN_CODES + NGX_HTTP_LEVEL_200
                                         + NGX_HTTP_LEVEL_300
                                         + NGX_HTTP_LEVEL_400;
        switch (error) {
            case NGX_HTTP_TO_HTTPS:
            case NGX_HTTPS_CERT_ERROR:
            case NGX_HTTPS_NO_CERT:
                r->err_status = NGX_HTTP_BAD_REQUEST;
                break;
        }
    }

    return ngx_http_send_special_response(r, clcf, err);
}


static ngx_int_t
ngx_http_send_error_page(ngx_http_request_t *r, ngx_http_err_page_t *err_page)
{
    u_char                     ch, *p, *last;
    ngx_str_t                 *uri, *args, u, a;
    ngx_table_elt_t           *location;
    ngx_http_core_loc_conf_t  *clcf;

    r->err_status = err_page->overwrite;

    r->zero_in_uri = 0;

    if (err_page->uri_lengths) {
        if (ngx_http_script_run(r, &u, err_page->uri_lengths->elts, 0,
                                err_page->uri_values->elts)
            == NULL)
        {
            return NGX_ERROR;
        }

        p = u.data;
        uri = &u;
        args = NULL;

        if (*p == '/') {

            last = p + uri->len;

            while (p < last) {

                ch = *p++;

                if (ch == '?') {
                    a.len = last - p;
                    a.data = p;
                    args = &a;

                    u.len = p - 1 - u.data;

                    while (p < last) {
                        if (*p++ == '\0') {
                            r->zero_in_uri = 1;
                            break;
                        }
                    }

                    break;
                }

                if (ch == '\0') {
                    r->zero_in_uri = 1;
                    continue;
                }
            }
        }

    } else {
        uri = &err_page->uri;
        args = &err_page->args;
    }

    if (uri->data[0] == '/') {

        r->method = NGX_HTTP_GET;
        r->method_name = ngx_http_get_name;

        return ngx_http_internal_redirect(r, uri, args);
    }

    if (uri->data[0] == '@') {
        return ngx_http_named_location(r, uri);
    }

    location = ngx_list_push(&r->headers_out.headers);

    if (location == NULL) {
        return NGX_ERROR;
    }

    r->err_status = NGX_HTTP_MOVED_TEMPORARILY;

    location->hash = 1;
    location->key.len = sizeof("Location") - 1;
    location->key.data = (u_char *) "Location";
    location->value = *uri;

    r->headers_out.location = location;

    clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);

    if (clcf->msie_refresh && r->headers_in.msie) {
        return ngx_http_send_refresh(r);
    }

    return ngx_http_send_special_response(r, clcf, NGX_HTTP_MOVED_TEMPORARILY
                                                   - NGX_HTTP_MOVED_PERMANENTLY
                                                   + NGX_HTTP_LEVEL_200);
}


static ngx_int_t
ngx_http_send_special_response(ngx_http_request_t *r,
    ngx_http_core_loc_conf_t *clcf, ngx_uint_t err)
{
    u_char       *tail;
    size_t        len;
    ngx_int_t     rc;
    ngx_buf_t    *b;
    ngx_uint_t    msie_padding;
    ngx_chain_t   out[3];

    if (clcf->server_tokens) {
        len = sizeof(ngx_http_error_full_tail) - 1;
        tail = ngx_http_error_full_tail;

    } else {
        len = sizeof(ngx_http_error_tail) - 1;
        tail = ngx_http_error_tail;
    }

    msie_padding = 0;

    if (!r->zero_body) {
        if (ngx_http_error_pages[err].len) {
            r->headers_out.content_length_n = ngx_http_error_pages[err].len
                                              + len;
            if (clcf->msie_padding
                && r->headers_in.msie
                && r->http_version >= NGX_HTTP_VERSION_10
                && err >= NGX_HTTP_LEVEL_300)
            {
                r->headers_out.content_length_n +=
                                                sizeof(ngx_http_msie_stub) - 1;
                msie_padding = 1;
            }

            r->headers_out.content_type_len = sizeof("text/html") - 1;
            r->headers_out.content_type.len = sizeof("text/html") - 1;
            r->headers_out.content_type.data = (u_char *) "text/html";

        } else {
            r->headers_out.content_length_n = -1;
        }

    } else {
        r->headers_out.content_length_n = 0;
        err = 0;
    }

    if (r->headers_out.content_length) {
        r->headers_out.content_length->hash = 0;
        r->headers_out.content_length = NULL;
    }

    ngx_http_clear_accept_ranges(r);
    ngx_http_clear_last_modified(r);

    rc = ngx_http_send_header(r);

    if (rc == NGX_ERROR || r->header_only) {
        return rc;
    }

    if (ngx_http_error_pages[err].len == 0) {
        return NGX_OK;
    }

    b = ngx_calloc_buf(r->pool);
    if (b == NULL) {
        return NGX_ERROR;
    }

    b->memory = 1;
    b->pos = ngx_http_error_pages[err].data;
    b->last = ngx_http_error_pages[err].data + ngx_http_error_pages[err].len;

    out[0].buf = b;
    out[0].next = &out[1];

    b = ngx_calloc_buf(r->pool);
    if (b == NULL) {
        return NGX_ERROR;
    }

    b->memory = 1;

    b->pos = tail;
    b->last = tail + len;

    out[1].buf = b;
    out[1].next = NULL;;

    if (msie_padding) {
        b = ngx_calloc_buf(r->pool);
        if (b == NULL) {
            return NGX_ERROR;
        }

        b->memory = 1;
        b->pos = ngx_http_msie_stub;
        b->last = ngx_http_msie_stub + sizeof(ngx_http_msie_stub) - 1;

        out[1].next = &out[2];
        out[2].buf = b;
        out[2].next = NULL;;
    }

    if (r == r->main) {
        b->last_buf = 1;
    }

    b->last_in_chain = 1;

    return ngx_http_output_filter(r, &out[0]);
}


static ngx_int_t
ngx_http_send_refresh(ngx_http_request_t *r)
{
    u_char       *p, *location;
    size_t        len, size;
    uintptr_t     escape;
    ngx_int_t     rc;
    ngx_buf_t    *b;
    ngx_chain_t   out;

    len = r->headers_out.location->value.len;
    location = r->headers_out.location->value.data;

    escape = 2 * ngx_escape_uri(NULL, location, len, NGX_ESCAPE_REFRESH);

    size = sizeof(ngx_http_msie_refresh_head) - 1
           + escape + len
           + sizeof(ngx_http_msie_refresh_tail) - 1;

    r->err_status = NGX_HTTP_OK;

    r->headers_out.content_type_len = sizeof("text/html") - 1;
    r->headers_out.content_type.len = sizeof("text/html") - 1;
    r->headers_out.content_type.data = (u_char *) "text/html";

    r->headers_out.location->hash = 0;
    r->headers_out.location = NULL;

    r->headers_out.content_length_n = size;

    if (r->headers_out.content_length) {
        r->headers_out.content_length->hash = 0;
        r->headers_out.content_length = NULL;
    }

    ngx_http_clear_accept_ranges(r);
    ngx_http_clear_last_modified(r);

    rc = ngx_http_send_header(r);

    if (rc == NGX_ERROR || r->header_only) {
        return rc;
    }

    b = ngx_create_temp_buf(r->pool, size);
    if (b == NULL) {
        return NGX_ERROR;
    }

    p = ngx_cpymem(b->pos, ngx_http_msie_refresh_head,
                   sizeof(ngx_http_msie_refresh_head) - 1);

    if (escape == 0) {
        p = ngx_cpymem(p, location, len);

    } else {
        p = (u_char *) ngx_escape_uri(p, location, len, NGX_ESCAPE_REFRESH);
    }

    b->last = ngx_cpymem(p, ngx_http_msie_refresh_tail,
                         sizeof(ngx_http_msie_refresh_tail) - 1);

    b->last_buf = 1;
    b->last_in_chain = 1;

    out.buf = b;
    out.next = NULL;

    return ngx_http_output_filter(r, &out);
}