cgi: add spawn reap callback

lib/core-net/close.c

@@ -683,6 +683,7 @@ __lws_close_free_wsi_final(struct lws *wsi)
 #ifdef LWS_WITH_CGI
 	if (wsi->http.cgi) {
 		lws_spawn_piped_destroy(&wsi->http.cgi->lsp);
+		lws_sul_cancel(&wsi->http.cgi->sul_grace);
 		lws_free_set_NULL(wsi->http.cgi);
 	}
 #endif

lib/core-net/dummy-callback.c

@@ -337,12 +337,16 @@ lws_callback_http_dummy(struct lws *wsi, enum lws_callback_reasons reason,
 			else
 				wsi->reason_bf &= ~LWS_CB_REASON_AUX_BF__CGI;
 
-			if (wsi->http.cgi && wsi->http.cgi->cgi_transaction_over)
+			if (wsi->http.cgi && wsi->http.cgi->cgi_transaction_over) {
+				lwsl_notice("%s: txn over\n", __func__);
 				return -1;
+			}
+
 			break;
 		}
 
-		if (wsi->reason_bf & LWS_CB_REASON_AUX_BF__CGI_CHUNK_END) {
+		if ((wsi->http.cgi && wsi->http.cgi->cgi_transaction_over) ||
+		    (wsi->reason_bf & LWS_CB_REASON_AUX_BF__CGI_CHUNK_END)) {
 			if (!wsi->mux_substream) {
 				memcpy(buf + LWS_PRE, "0\x0d\x0a\x0d\x0a", 5);
 				lwsl_debug("writing chunk term and exiting\n");
@@ -791,6 +795,7 @@ lws_callback_http_dummy(struct lws *wsi, enum lws_callback_reasons reason,
 		if (wsi->http.cgi->post_in_expected && args->stdwsi[LWS_STDIN] &&
 		    args->stdwsi[LWS_STDIN]->desc.filefd > 0) {
 			wsi->http.cgi->post_in_expected -= n;
+
 			if (!wsi->http.cgi->post_in_expected) {
 				struct lws *siwsi = args->stdwsi[LWS_STDIN];
 
@@ -803,8 +808,9 @@ lws_callback_http_dummy(struct lws *wsi, enum lws_callback_reasons reason,
 				 */
 
 				lwsl_notice("%s: expected POST in end: "
-					   "closing stdin wsi %p, fd %d\n",
-					   __func__, siwsi, siwsi->desc.sockfd);
+					    "closing stdin wsi %p, fd %d\n",
+					    __func__, siwsi,
+					    siwsi->desc.sockfd);
 
 				/*
 				 * We don't want the child / parent relationship
@@ -815,6 +821,7 @@ lws_callback_http_dummy(struct lws *wsi, enum lws_callback_reasons reason,
 				lws_remove_child_from_any_parent(siwsi);
 				lws_wsi_close(siwsi, LWS_TO_KILL_ASYNC);
 				wsi->http.cgi->lsp->stdwsi[LWS_STDIN] = NULL;
+				lws_spawn_stdwsi_closed(wsi->http.cgi->lsp, siwsi);
 			}
 		}
 

lib/roles/cgi/cgi-server.c

@@ -68,6 +68,43 @@ urlencode(const char *in, int inlen, char *out, int outlen)
 	return out - start;
 }
 
+static void
+lws_cgi_grace(lws_sorted_usec_list_t *sul)
+{
+	struct lws_cgi *cgi = lws_container_of(sul, struct lws_cgi, sul_grace);
+
+	/* act on the reap cb from earlier */
+
+	lwsl_notice("%s: wsi %p\n", __func__, cgi->wsi);
+
+	if (!cgi->wsi->http.cgi->post_in_expected)
+		cgi->wsi->http.cgi->cgi_transaction_over = 1;
+
+	lws_callback_on_writable(cgi->wsi);
+}
+
+
+static void
+lws_cgi_reap_cb(void *opaque, lws_usec_t *accounting, siginfo_t *si,
+		 int we_killed_him)
+{
+	struct lws *wsi = (struct lws *)opaque;
+
+	/*
+	 * The cgi has come to an end, by itself or with a signal...
+	 */
+
+	lwsl_notice("%s: wsi %p post_in_expected %d\n", __func__, wsi,
+			(int)wsi->http.cgi->post_in_expected);
+
+	/*
+	 * Grace period to handle the incoming stdout
+	 */
+
+	lws_sul_schedule(wsi->context, wsi->tsi, &wsi->http.cgi->sul_grace,
+			 lws_cgi_grace, 1 * LWS_US_PER_SEC);
+}
+
 int
 lws_cgi(struct lws *wsi, const char * const *exec_array,
 	int script_uri_path_len, int timeout_secs,
@@ -357,6 +394,8 @@ lws_cgi(struct lws *wsi, const char * const *exec_array,
 	info.vh = wsi->vhost;
 	info.ops = &role_ops_cgi;
 	info.plsp = &wsi->http.cgi->lsp;
+	info.opaque = wsi;
+	info.reap_cb = lws_cgi_reap_cb;
 
 	/*
 	 * Actually having made the env, as a cgi we don't need the ah
@@ -386,6 +425,7 @@ lws_cgi(struct lws *wsi, const char * const *exec_array,
 	return 0;
 
 bail:
+	lws_sul_cancel(&wsi->http.cgi->sul_grace);
 	lws_free_set_NULL(wsi->http.cgi);
 
 	lwsl_err("%s: failed\n", __func__);
@@ -561,7 +601,7 @@ post_hpack_recode:
 
 			cmd = LWS_WRITE_HTTP_HEADERS_CONTINUATION;
 			if (wsi->http.cgi->headers_dumped + n !=
-			    wsi->http.cgi->headers_pos) {
+						wsi->http.cgi->headers_pos) {
 				lwsl_notice("adding no fin flag\n");
 				cmd |= LWS_WRITE_NO_FIN;
 			}
@@ -578,14 +618,21 @@ post_hpack_recode:
 			    wsi->http.cgi->headers_pos) {
 				wsi->hdr_state = LHCS_PAYLOAD;
 				lws_free_set_NULL(wsi->http.cgi->headers_buf);
-				lwsl_debug("freed cgi headers\n");
+				lwsl_debug("%s: freed cgi headers\n", __func__);
+
+				if (wsi->http.cgi->post_in_expected) {
+					lwsl_notice("%s: post data still expected, asking for writeable\n", __func__);
+					lws_callback_on_writable(wsi);
+				}
+
 			} else {
 				wsi->reason_bf |=
 					LWS_CB_REASON_AUX_BF__CGI_HEADERS;
 				lws_callback_on_writable(wsi);
 			}
 
-			/* writeability becomes uncertain now we wrote
+			/*
+			 * writeability becomes uncertain now we wrote
 			 * something, we must return to the event loop
 			 */
 			return 0;
@@ -962,7 +1009,7 @@ lws_cgi_kill_terminated(struct lws_context_per_thread *pt)
 		cgi = *pcgi;
 		pcgi = &(*pcgi)->cgi_list;
 
-		if (cgi->lsp->child_pid <= 0)
+		if (!cgi || !cgi->lsp || cgi->lsp->child_pid <= 0)
 			continue;
 
 		/* we deferred killing him after reaping his PID */
@@ -1040,7 +1087,7 @@ lws_cgi_remove_and_kill(struct lws *wsi)
 		pcgi = &(*pcgi)->cgi_list;
 	}
 	if (wsi->http.cgi->headers_buf) {
-		lwsl_debug("close: freed cgi headers\n");
+		lwsl_debug("%s: close: freed cgi headers\n", __func__);
 		lws_free_set_NULL(wsi->http.cgi->headers_buf);
 	}
 	/* we have a cgi going, we must kill it */

lib/roles/cgi/ops-cgi.c

@@ -46,6 +46,27 @@ rops_handle_POLLIN_cgi(struct lws_context_per_thread *pt, struct lws *wsi,
 		return LWS_HPI_RET_WSI_ALREADY_DIED;
 	}
 
+	if (!wsi->parent) {
+		lwsl_notice("%s: stdwsi content with parent\n",
+				__func__);
+
+		return LWS_HPI_RET_HANDLED;
+	}
+
+	if (!wsi->parent->http.cgi) {
+		lwsl_notice("%s: stdwsi content with deleted cgi object\n",
+				__func__);
+
+		return LWS_HPI_RET_HANDLED;
+	}
+
+	if (!wsi->parent->http.cgi->lsp) {
+		lwsl_notice("%s: stdwsi content with reaped lsp\n",
+				__func__);
+
+		return LWS_HPI_RET_HANDLED;
+	}
+
 	args.ch = wsi->lsp_channel;
 	args.stdwsi = &wsi->parent->http.cgi->lsp->stdwsi[0];
 	args.hdr_state = wsi->hdr_state;

lib/roles/cgi/private-lib-roles-cgi.h

@@ -55,7 +55,8 @@ struct lws;
 struct lws_cgi {
 	struct lws_cgi *cgi_list;
 
-	struct lws_spawn_piped *lsp;
+	struct lws_spawn_piped		*lsp;
+	lws_sorted_usec_list_t		sul_grace;
 
 	struct lws *wsi; /* owner */
 	unsigned char *headers_buf;

lib/roles/http/server/server.c

@@ -2345,6 +2345,7 @@ lws_http_transaction_completed(struct lws *wsi)
 		wsi->http.cgi_transaction_complete = 1;
 		lws_cgi_remove_and_kill(wsi);
 		lws_spawn_piped_destroy(&wsi->http.cgi->lsp);
+		lws_sul_cancel(&wsi->http.cgi->sul_grace);
 
 		lws_free_set_NULL(wsi->http.cgi);
 		wsi->http.cgi_transaction_complete = 0;

minimal-examples/http-server/minimal-http-server-cgi/my-cgi-script.sh

@@ -31,6 +31,6 @@ fi
 
 echo "<br/>done"
 echo "</body></html>"
-
+sleep 0.5
 exit 0