Commit 9bf06958 authored by William A. Rowe Jr's avatar William A. Rowe Jr
Browse files 

  Where any response is sent, return OK from the handler.  Where there
  is no response (but a status code) return the code.  This patch adds
  a great number of debugging emits for failed ap_pass_brigade calls,
  to help diagnose failure cases, and disambiguates OK from APR_SUCCESS. 

PR: 40470
Submitted by: wrowe, Matt Eaton <asf divinehawk.com>


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@492333 13f79535-47bb-0310-9956-ffa450edef68
parent 1ad85e20

modules/arch/win32/mod_isapi.c

+48 −16
Changes for modules/arch/win32/mod_isapi.c: 48 added lines, 16 removed lines.
Original line number Diff line number Diff line
@@ -815,7 +815,7 @@ int APR_THREAD_FUNC WriteClient(isapi_cid *cid, 
    char *buf_data = (char*)buf_ptr;

    apr_bucket_brigade *bb;

    apr_bucket *b;

    apr_status_t rv;

    apr_status_t rv = APR_SUCCESS;



    if (!cid->headers_set) {

        /* It appears that the foxisapi module and other clients
@@ -841,10 +841,14 @@ int APR_THREAD_FUNC WriteClient(isapi_cid *cid, 
        APR_BRIGADE_INSERT_TAIL(bb, b);

        rv = ap_pass_brigade(r->output_filters, bb);

        cid->response_sent = 1;

        if (rv != APR_SUCCESS)

            ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r,

                          "ISAPI: WriteClient ap_pass_brigade "

                          "failed: %s", r->filename);

    }



    if ((flags & HSE_IO_ASYNC) && cid->completion) {

        if (rv == OK) {

        if (rv == APR_SUCCESS) {

            cid->completion(cid->ecb, cid->completion_arg,

                            *size_arg, ERROR_SUCCESS);

        }
@@ -928,6 +932,11 @@ int APR_THREAD_FUNC ServerSupportFunction(isapi_cid *cid, 
            APR_BRIGADE_INSERT_TAIL(bb, b);

            rv = ap_pass_brigade(cid->r->output_filters, bb);

            cid->response_sent = 1;

            if (rv != APR_SUCCESS)

                ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r,

                              "ISAPI: ServerSupport function "

                              "HSE_REQ_SEND_RESPONSE_HEADER "

                              "ap_pass_brigade failed: %s", r->filename);

            return (rv == APR_SUCCESS);

        }

        /* Deliberately hold off sending 'just the headers' to begin to
@@ -1125,13 +1134,18 @@ int APR_THREAD_FUNC ServerSupportFunction(isapi_cid *cid, 
        APR_BRIGADE_INSERT_TAIL(bb, b);

        rv = ap_pass_brigade(r->output_filters, bb);

        cid->response_sent = 1;

        if (rv != APR_SUCCESS)

            ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r,

                          "ISAPI: ServerSupport function "

                          "HSE_REQ_TRANSMIT_FILE "

                          "ap_pass_brigade failed: %s", r->filename);



        /* Use tf->pfnHseIO + tf->pContext, or if NULL, then use cid->fnIOComplete

         * pass pContect to the HseIO callback.

         */

        if (tf->dwFlags & HSE_IO_ASYNC) {

            if (tf->pfnHseIO) {

                if (rv == OK) {

                if (rv == APR_SUCCESS) {

                    tf->pfnHseIO(cid->ecb, tf->pContext,

                                 ERROR_SUCCESS, sent);

                }
@@ -1141,7 +1155,7 @@ int APR_THREAD_FUNC ServerSupportFunction(isapi_cid *cid, 
                }

            }

            else if (cid->completion) {

                if (rv == OK) {

                if (rv == APR_SUCCESS) {

                    cid->completion(cid->ecb, cid->completion_arg,

                                    sent, ERROR_SUCCESS);

                }
@@ -1191,6 +1205,14 @@ int APR_THREAD_FUNC ServerSupportFunction(isapi_cid *cid, 
        }



        if ((*data_type & HSE_IO_ASYNC) && cid->completion) {

            /* XXX: Many authors issue their next HSE_REQ_ASYNC_READ_CLIENT

             * within the completion logic.  An example is MS's own PSDK

             * sample web/iis/extensions/io/ASyncRead.  This potentially

             * leads to stack exhaustion.  To refactor, the notification 

             * logic needs to move to isapi_handler() - differentiating

             * the cid->completed event with a new flag to indicate 

             * an async-notice versus the async request completed.

             */

            if (res >= 0) {

                cid->completion(cid->ecb, cid->completion_arg,

                                read, ERROR_SUCCESS);
@@ -1325,6 +1347,11 @@ int APR_THREAD_FUNC ServerSupportFunction(isapi_cid *cid, 
            APR_BRIGADE_INSERT_TAIL(bb, b);

            rv = ap_pass_brigade(cid->r->output_filters, bb);

            cid->response_sent = 1;

            if (rv != APR_SUCCESS)

                ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r,

                              "ISAPI: ServerSupport function "

                              "HSE_REQ_SEND_RESPONSE_HEADER_EX "

                              "ap_pass_brigade failed: %s", r->filename);

            return (rv == APR_SUCCESS);

        }

        /* Deliberately hold off sending 'just the headers' to begin to
@@ -1600,21 +1627,23 @@ apr_status_t isapi_handler (request_rec *r) 
        case HSE_STATUS_ERROR:

            /* end response if we have yet to do so.

             */

            ap_log_rerror(APLOG_MARK, APLOG_WARNING, apr_get_os_error(), r,

                          "ISAPI: HSE_STATUS_ERROR result from "

                          "HttpExtensionProc(): %s", r->filename);

            r->status = HTTP_INTERNAL_SERVER_ERROR;

            break;



        default:

            /* TODO: log unrecognized retval for debugging

             */

             ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r,

                           "ISAPI: return code %d from HttpExtensionProc() "

                           "was not not recognized", rv);

            ap_log_rerror(APLOG_MARK, APLOG_WARNING, apr_get_os_error(), r,

                          "ISAPI: unrecognized result code %d "

                          "from HttpExtensionProc(): %s ", 

                          rv, r->filename);

            r->status = HTTP_INTERNAL_SERVER_ERROR;

            break;

    }



    /* Flush the response now, including headers-only responses */

    if (cid->headers_set) {

    if (cid->headers_set || cid->response_sent) {

        conn_rec *c = r->connection;

        apr_bucket_brigade *bb;

        apr_bucket *b;
@@ -1623,13 +1652,16 @@ apr_status_t isapi_handler (request_rec *r) 
        bb = apr_brigade_create(r->pool, c->bucket_alloc);

        b = apr_bucket_eos_create(c->bucket_alloc);

        APR_BRIGADE_INSERT_TAIL(bb, b);

        b = apr_bucket_flush_create(c->bucket_alloc);

        APR_BRIGADE_INSERT_TAIL(bb, b);

        rv = ap_pass_brigade(r->output_filters, bb);

        cid->response_sent = 1;



        return (rv == APR_SUCCESS);

        /* NOT r->status or cid->r->status, even if it has changed. */

        if (rv != APR_SUCCESS) {

            ap_log_rerror(APLOG_MARK, APLOG_DEBUG, rv, r,

                          "ISAPI: ap_pass_brigade failed to "

                          "complete the response: %s ", r->filename);

        }



        return OK; /* NOT r->status, even if it has changed. */

    }



    /* As the client returned no error, and if we did not error out
@@ -1639,8 +1671,8 @@ apr_status_t isapi_handler (request_rec *r) 
        r->status = cid->ecb->dwHttpStatusCode;

    }



    /* For all missing-response situations simply return the status.

     * and let the core deal respond to the client.

    /* For all missing-response situations simply return the status,

     * and let the core respond to the client.

     */

    return r->status;

}