Integrate #1561 with some minor tweaks - add MG_ENABLE_POLL for poll() support

mongoose.c

@@ -3926,6 +3926,7 @@ struct mg_connection *mg_sntp_connect(struct mg_mgr *mgr, const char *url,
 
 
 
+
 #if MG_ENABLE_SOCKET
 #if MG_ARCH == MG_ARCH_WIN32 && MG_ENABLE_WINSOCK
 #define MG_SOCK_ERRNO WSAGetLastError()
@@ -4393,6 +4394,38 @@ static void mg_iotest(struct mg_mgr *mgr, int ms) {
     FreeRTOS_FD_CLR(c->fd, mgr->ss,
                     eSELECT_READ | eSELECT_EXCEPT | eSELECT_WRITE);
   }
+#elif MG_ENABLE_POLL
+  size_t i = 0, n = 0;
+  for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next) n++;
+  struct pollfd fds[n == 0 ? 1 : n];  // Avoid zero-length VLA
+
+  memset(fds, 0, sizeof(fds));
+  for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next, i++) {
+    if (c->is_closing || c->is_resolving || FD(c) == INVALID_SOCKET) {
+      // No valid socket yet, ignore
+    } else {
+      fds[i].fd = FD(c);
+      fds[i].events |= POLLIN;
+      if (c->is_connecting || (c->send.len > 0 && c->is_tls_hs == 0)) {
+        fds[i].events |= POLLOUT;
+      }
+    }
+  }
+
+  if (poll(fds, n, ms) < 0) {
+    MG_ERROR(("poll failed, errno: %d", MG_SOCK_ERRNO));
+  } else {
+    i = 0;
+    for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next, i++) {
+      if (c->is_closing || c->is_resolving || FD(c) == INVALID_SOCKET) {
+        // No valid socket yet, ignore
+      } else {
+        c->is_readable = (unsigned) (fds[i].revents & POLLIN ? true : false);
+        c->is_writable = (unsigned) (fds[i].revents & POLLOUT ? true : false);
+        fds[i].revents = 0;
+      }
+    }
+  }
 #else
   struct timeval tv = {ms / 1000, (ms % 1000) * 1000}, tv_zero = {0, 0};
   struct mg_connection *c;

mongoose.h

@@ -436,7 +436,11 @@ extern int SockSet(SOCKET hSock, int Type, int Prop, void *pbuf, int size);
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#if MG_ENABLE_POLL
+#include <poll.h>
+#else
 #include <sys/select.h>
+#endif
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/time.h>
@@ -578,6 +582,10 @@ int sscanf(const char *, const char *, ...);
 #define MG_ENABLE_MIP 0
 #endif
 
+#ifndef MG_ENABLE_POLL
+#define MG_ENABLE_POLL 0
+#endif
+
 #ifndef MG_ENABLE_FATFS
 #define MG_ENABLE_FATFS 0
 #endif

src/arch_unix.h

@@ -22,7 +22,11 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#if MG_ENABLE_POLL
+#include <poll.h>
+#else
 #include <sys/select.h>
+#endif
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/time.h>

src/config.h

@@ -4,6 +4,10 @@
 #define MG_ENABLE_MIP 0
 #endif
 
+#ifndef MG_ENABLE_POLL
+#define MG_ENABLE_POLL 0
+#endif
+
 #ifndef MG_ENABLE_FATFS
 #define MG_ENABLE_FATFS 0
 #endif

src/sock.c

@@ -1,3 +1,4 @@
+#include "arch.h"
 #include "dns.h"
 #include "event.h"
 #include "log.h"
@@ -475,6 +476,38 @@ static void mg_iotest(struct mg_mgr *mgr, int ms) {
     FreeRTOS_FD_CLR(c->fd, mgr->ss,
                     eSELECT_READ | eSELECT_EXCEPT | eSELECT_WRITE);
   }
+#elif MG_ENABLE_POLL
+  size_t i = 0, n = 0;
+  for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next) n++;
+  struct pollfd fds[n == 0 ? 1 : n];  // Avoid zero-length VLA
+
+  memset(fds, 0, sizeof(fds));
+  for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next, i++) {
+    if (c->is_closing || c->is_resolving || FD(c) == INVALID_SOCKET) {
+      // No valid socket yet, ignore
+    } else {
+      fds[i].fd = FD(c);
+      fds[i].events |= POLLIN;
+      if (c->is_connecting || (c->send.len > 0 && c->is_tls_hs == 0)) {
+        fds[i].events |= POLLOUT;
+      }
+    }
+  }
+
+  if (poll(fds, n, ms) < 0) {
+    MG_ERROR(("poll failed, errno: %d", MG_SOCK_ERRNO));
+  } else {
+    i = 0;
+    for (struct mg_connection *c = mgr->conns; c != NULL; c = c->next, i++) {
+      if (c->is_closing || c->is_resolving || FD(c) == INVALID_SOCKET) {
+        // No valid socket yet, ignore
+      } else {
+        c->is_readable = (unsigned) (fds[i].revents & POLLIN ? true : false);
+        c->is_writable = (unsigned) (fds[i].revents & POLLOUT ? true : false);
+        fds[i].revents = 0;
+      }
+    }
+  }
 #else
   struct timeval tv = {ms / 1000, (ms % 1000) * 1000}, tv_zero = {0, 0};
   struct mg_connection *c;