support ioctl-FIONREAD

src/library.js

@@ -6368,6 +6368,7 @@ LibraryManager.library = {
   connect__deps: ['$Sockets', '_inet_ntop_raw', 'ntohs'],
   connect: function(fd, addr, addrlen) {
     var info = Sockets.fds[fd];
+    if (!info) return -1;
     info.connected = true;
     info.addr = getValue(addr + Sockets.sockaddr_in_layout.sin_addr, 'i32');
     info.port = _ntohs(getValue(addr + Sockets.sockaddr_in_layout.sin_port, 'i16'));
@@ -6396,6 +6397,7 @@ LibraryManager.library = {
   recv__deps: ['$Sockets'],
   recv: function(fd, buf, len, flags) {
     var info = Sockets.fds[fd];
+    if (!info) return -1;
     if (info.bufferWrite == info.bufferRead) {
       ___setErrNo(ERRNO_CODES.EAGAIN); // no data, and all sockets are nonblocking, so this is the right behavior
       return 0; // should this be -1 like the spec says?
@@ -6412,10 +6414,23 @@ LibraryManager.library = {
   },
 
   shutdown: function(fd, how) {
-    Sockets.fds[fd].socket.close();
+    var info = Sockets.fds[fd];
+    if (!info) return -1;
+    info.socket.close();
     Sockets.fds[fd] = null;
   },
 
+  ioctl: function(fd, request, varargs) {
+    var info = Sockets.fds[fd];
+    if (!info) return -1;
+    var start = info.bufferRead;
+    var end = info.bufferWrite;
+    if (end < start) end += Sockets.BUFFER_SIZE;
+    var dest = {{{ makeGetValue('varargs', '0', 'i32') }}};
+    {{{ makeSetValue('dest', '0', 'end - start', 'i32') }}};
+    return 0;
+  },
+
   // ==========================================================================
   // emscripten.h
   // ==========================================================================

src/settings.js

@@ -1126,6 +1126,7 @@ var C_DEFINES = {'SI_MESGQ': '5',
    '_CS_POSIX_V7_LP64_OFF64_LDFLAGS': '10',
    '_SC_TTY_NAME_MAX': '41',
    'AF_INET': '1',
-   'AF_INET6': '6'
+   'AF_INET6': '6',
+   'FIONREAD': '1'
 };
 

system/include/sys/ioctl.h

@@ -11,6 +11,8 @@ extern "C" {
 #define TIOCGSIZE 80 // bogus
 #define TIOCGWINSZ 80 // bogus
 
+#define FIONREAD 1
+
 int ioctl(int d, int request, ...);
 
 #define SO_RCVTIMEO 1000

tests/websockets.c

@@ -7,6 +7,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <sys/ioctl.h>
 #if EMSCRIPTEN
 #include <emscripten.h>
 #endif
@@ -17,8 +18,11 @@ int SocketFD;
 
 unsigned int get_all_buf(int sock, char* output, unsigned int maxsize)
 {
-  char buffer[1024];
+  int bytes;
+  if (ioctl(sock, FIONREAD, &bytes)) return 0;
+  if (bytes == 0) return 0;
 
+  char buffer[1024];
   int n;
   unsigned int offset = 0;
   while((errno = 0, (n = recv(sock, buffer, sizeof(buffer), 0))>0) ||