Fix ioctl() and FIONREAD for sockets on Windows

This change fixes an issue where using FIONREAD would cause control flow
to jump to null, due to a _weaken() reference that I refactored long ago

libc/calls/ioctl.c

@@ -38,6 +38,7 @@
 #include "libc/nt/iphlpapi.h"
 #include "libc/nt/runtime.h"
 #include "libc/nt/struct/ipadapteraddresses.h"
+#include "libc/nt/thunk/msabi.h"
 #include "libc/nt/winsock.h"
 #include "libc/runtime/runtime.h"
 #include "libc/runtime/stack.h"
@@ -59,6 +60,8 @@
 #define MAX_UNICAST_ADDR 32
 #define MAX_NAME_CLASH   ((int)('z' - 'a')) /* Allow a..z */
 
+__msabi extern typeof(__sys_ioctlsocket_nt) *const __imp_ioctlsocket;
+
 static struct HostAdapterInfoNode {
   struct HostAdapterInfoNode *next;
   char name[IFNAMSIZ]; /* Obtained from FriendlyName */
@@ -76,7 +79,7 @@ static int ioctl_default(int fd, unsigned long request, void *arg) {
   } else if (__isfdopen(fd)) {
     if (g_fds.p[fd].kind == kFdSocket) {
       handle = g_fds.p[fd].handle;
-      if ((rc = _weaken(__sys_ioctlsocket_nt)(handle, request, arg)) != -1) {
+      if ((rc = __imp_ioctlsocket(handle, request, arg)) != -1) {
         return rc;
       } else {
         return _weaken(__winsockerr)();
@@ -97,7 +100,7 @@ static int ioctl_fionread(int fd, uint32_t *arg) {
   } else if (__isfdopen(fd)) {
     handle = g_fds.p[fd].handle;
     if (g_fds.p[fd].kind == kFdSocket) {
-      if ((rc = _weaken(__sys_ioctlsocket_nt)(handle, FIONREAD, arg)) != -1) {
+      if ((rc = __imp_ioctlsocket(handle, FIONREAD, arg)) != -1) {
         return rc;
       } else {
         return _weaken(__winsockerr)();

libc/sock/recv-nt.c

@@ -39,7 +39,7 @@ struct RecvArgs {
   struct NtIovec iovnt[16];
 };
 
-static textwindows int sys_recv_nt_start(int64_t handle,
+textwindows static int sys_recv_nt_start(int64_t handle,
                                          struct NtOverlapped *overlap,
                                          uint32_t *flags, void *arg) {
   struct RecvArgs *args = arg;

libc/sock/recvfrom-nt.c

@@ -42,7 +42,7 @@ struct RecvFromArgs {
   struct NtIovec iovnt[16];
 };
 
-static textwindows int sys_recvfrom_nt_start(int64_t handle,
+textwindows static int sys_recvfrom_nt_start(int64_t handle,
                                              struct NtOverlapped *overlap,
                                              uint32_t *flags, void *arg) {
   struct RecvFromArgs *args = arg;

libc/sock/send-nt.c

@@ -38,7 +38,7 @@ struct SendArgs {
   struct NtIovec iovnt[16];
 };
 
-static textwindows int sys_send_nt_start(int64_t handle,
+textwindows static int sys_send_nt_start(int64_t handle,
                                          struct NtOverlapped *overlap,
                                          uint32_t *flags, void *arg) {
   struct SendArgs *args = arg;

libc/sysv/consts.sh

@@ -19,10 +19,6 @@
 dir=libc/sysv/consts
 . libc/sysv/gen.sh
 
-# syscon	errno	EALREADY				114			114			37			37			37			37			37			10037			# connection already in progress; bsd consensus; WSAEALREADY; raised by connect(2), send(2), ip(7)
-# syscon	errno	EINPROGRESS				115			115			36			36			36			36			36			10036			# bsd consensus; WSAEINPROGRESS; raised by connect(2) w/ O_NONBLOCK
-# syscon	errno	EISCONN					106			106			56			56			56			56			56			10056			# socket is connected; bsd consensus; WSAEISCONN; raised by connect(2), send(2), unix(7), ip(7)
-
 #	The Fifth Bell System, Community Edition
 #	» catalogue of carnage
 #

test/posix/socket_fionread_test.c

@@ -0,0 +1,69 @@
+#include <arpa/inet.h>
+#include <cosmo.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <netinet/in.h>
+#include <poll.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+int main() {
+
+  // create server socket
+  int server_fd;
+  struct sockaddr_in address;
+  int addrlen = sizeof(address);
+  if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
+    return 1;
+  address.sin_family = AF_INET;
+  address.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+  address.sin_port = 0;  // let os assign random port
+  if (bind(server_fd, (struct sockaddr *)&address, sizeof(address)))
+    return 2;
+  if (getsockname(server_fd, (struct sockaddr *)&address,
+                  (socklen_t *)&addrlen))
+    return 3;
+  if (listen(server_fd, SOMAXCONN))
+    return 4;
+
+  // create client socket
+  int client_fd;
+  if ((client_fd = socket(AF_INET, SOCK_STREAM, 0)) == -1)
+    return 6;
+  if (connect(client_fd, (struct sockaddr *)&address, sizeof(address)))
+    return 7;
+
+  // accept client and send data
+  int server_client_fd;
+  if ((server_client_fd = accept(server_fd, 0, 0)) == -1)
+    return 8;
+  if (write(server_client_fd, "hi", 2) != 2)
+    return 9;
+
+  // poll to be safe (important for mac/bsd)
+  struct pollfd fds[] = {{client_fd, POLLIN}};
+  if (poll(fds, 1, -1u) != 1)
+    return 10;
+
+  // ask how many bytes we can read
+  uint32_t bytes_available;
+  if (ioctl(client_fd, FIONREAD, &bytes_available))
+    return 11;
+  if (bytes_available != 2) {
+    printf("wut %d\n", bytes_available);
+    return 12;
+  }
+
+  // clean up
+  if (close(client_fd))
+    return 13;
+  if (close(server_fd))
+    return 14;
+
+  CheckForMemoryLeaks();
+}