add support for emscripten using upoll

CMakeLists.txt

@@ -126,7 +126,26 @@ elseif (CMAKE_SYSTEM_NAME STREQUAL "FreeBSD" OR CMAKE_SYSTEM_NAME STREQUAL "NetB
 
     list(APPEND EVENT_LOOP_DEFINES "KQUEUE")
     set(USE_S2N ON)
+elseif(CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
+    option(USE_VSOCK
+            "Build in support for VSOCK sockets"
+            OFF)
+
+    file(GLOB AWS_IO_OS_HEADERS
+            )
 
+    file(GLOB AWS_IO_OS_SRC
+            "source/emscripten/*.c"
+            "source/linux/*.c"
+            "source/posix/*.c"
+            )
+
+    set(EPOLL_SHIM_INCLUDE "source/emscripten")
+
+    set(PLATFORM_LIBS "")
+
+    set(EVENT_LOOP_DEFINE "EPOLL")
+    set(USE_S2N ON)
 endif()
 
 if (BYO_CRYPTO)
@@ -215,6 +234,7 @@ endif()
 target_include_directories(${PROJECT_NAME} PUBLIC
         $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
         $<INSTALL_INTERFACE:include>)
+target_include_directories(${PROJECT_NAME} PRIVATE ${EPOLL_SHIM_INCLUDE})
 
 aws_use_package(aws-c-common)
 aws_use_package(aws-c-cal)

source/emscripten/epoll.c

@@ -0,0 +1,35 @@
+#include <errno.h>
+#include <limits.h>
+#include <up.h>
+
+#include <sys/epoll.h>
+
+static upoll_t* ups[OPEN_MAX];
+static int index = 1;
+
+int
+epoll_create(int size)
+{
+        if (index >= OPEN_MAX) {
+                errno = ENFILE;
+                return -1;
+        }
+        ups[index++] = upoll_create(size);
+        return index - 1;
+}
+
+int
+epoll_ctl(int epfd, int op, int fd, struct epoll_event *event)
+{
+        upoll_t* upq = ups[epfd];
+        upoll_event_t* uevent = (upoll_event_t*) event;
+        return upoll_ctl(upq, op, fd, uevent);
+}
+
+int
+epoll_wait(int epfd, struct epoll_event *events, int maxevents, int timeout)
+{
+        upoll_t* upq = ups[epfd];
+        upoll_event_t* uevents = (upoll_event_t*) events;
+        return upoll_wait(upq, uevents, maxevents, timeout);
+}

source/emscripten/sys/epoll.h

@@ -0,0 +1,73 @@
+/* epoll.h
+ Copyright (c) fd0, All rights reserved.
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 3.0 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with this library.*/
+
+#ifndef	_SYS_EPOLL_H
+#define	_SYS_EPOLL_H 1
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#ifndef OPEN_MAX
+#define OPEN_MAX 256
+#endif
+
+#ifndef __EPOLL_PACKED
+# define __EPOLL_PACKED __attribute__ ((__packed__))
+#endif
+
+#define EPOLLIN  0x01
+#define EPOLLOUT 0x02
+#define EPOLLERR 0x04
+#define EPOLLET  0x08
+#define EPOLLHUP 0x010
+
+/* Valid opcodes ( "op" parameter ) to issue to epoll_ctl().  */
+#define EPOLL_CTL_ADD 1	/* Add a file descriptor to the interface.  */
+#define EPOLL_CTL_DEL 2	/* Remove a file descriptor from the interface.  */
+#define EPOLL_CTL_MOD 3	/* Change file descriptor epoll_event structure.  */
+
+typedef union epoll_data
+{
+  void *ptr;
+  int fd;
+  uint32_t u32;
+  uint64_t u64;
+} epoll_data_t;
+
+struct epoll_event
+{
+  uint32_t events; /* Epoll events */
+  epoll_data_t data; /* User data variable */
+};
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int
+epoll_create (int size);
+
+int
+epoll_ctl (int epfd, int op, int fd, struct epoll_event *event);
+
+int
+epoll_wait (int epfd, struct epoll_event *events, int maxevents, int timeout);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* sys/epoll.h */

source/emscripten/up.h

@@ -0,0 +1,48 @@
+#ifndef _UP_H_
+#define _UP_H_
+
+#include <stdlib.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#define UPOLL_CTL_ADD 1
+#define UPOLL_CTL_DEL 2
+#define UPOLL_CTL_MOD 3
+
+#define UPOLLIN  0x01
+#define UPOLLOUT 0x02
+#define UPOLLERR 0x04
+#define UPOLLET  0x08
+
+typedef struct upoll upoll_t;
+
+typedef union upoll_data {
+  void      *ptr;
+  intptr_t  fd;
+  uint32_t  u32;
+  uint64_t  u64;
+} upoll_data_t;
+
+typedef struct upoll_event {
+  uint32_t      events;
+  upoll_data_t  data;
+} upoll_event_t;
+
+upoll_t* upoll_create(uint32_t size);
+int upoll_ctl(upoll_t* upq, int op, intptr_t fd, upoll_event_t *event);
+int upoll_wait(upoll_t* upq, upoll_event_t *events, int maxevents, int timeout);
+void upoll_destroy(upoll_t* upq);
+
+intptr_t usocket(int domain, int type, int proto);
+intptr_t uaccept(intptr_t sock);
+
+int ubind(intptr_t sock, const char* name, const char* serv);
+int ulisten(intptr_t sock, int backlog);
+int uconnect(intptr_t sock, const char* name, const char* serv);
+int uclose(intptr_t sock);
+int uread(intptr_t fd, char* buf, size_t len);
+int uwrite(intptr_t fd, const char* buf, size_t len);
+int usocketpair(intptr_t socks[2], int async);
+
+#endif /* _UP_H_ */
+