Implemented <poll.h>.

2 files changed, 81 insertions, 0 deletions

diff --git a/src/library.js b/src/library.js
index 793454de..3088fb3c 100644
--- a/src/library.js
+++ b/src/library.js
@@ -857,6 +857,36 @@ LibraryManager.library = {
   },
 
   // ==========================================================================
+  // poll.h
+  // ==========================================================================
+
+  __pollfd_struct_layout: Types.structDefinitions.pollfd,
+  poll__deps: ['$FS', '__setErrNo', '$ERRNO_CODES', '__pollfd_struct_layout'],
+  poll: function(fds, nfds, timeout) {
+    // int poll(struct pollfd fds[], nfds_t nfds, int timeout);
+    // http://pubs.opengroup.org/onlinepubs/009695399/functions/poll.html
+    // NOTE: This is pretty much a no-op mimicing glibc.
+    var members = ___pollfd_struct_layout.members;
+    var nonzero = 0;
+    for (var i = 0; i < nfds; i++) {
+      var pollfd = fds + ___pollfd_struct_layout.size * i;
+      var fd = {{{ makeGetValue('pollfd', 'members.fd.offset', 'i32') }}};
+      var events = {{{ makeGetValue('pollfd', 'members.events.offset', 'i16') }}};
+      var revents = 0;
+      if (fd in FS.streams) {
+        var stream = FS.streams[fd];
+        if (events & 0x1) revents |= 0x1;  // POLLIN.
+        if (events & 0x4) revents |= 0x4;  // POLLOUT.
+      } else {
+        if (events & 0x20) revents |= 0x20;  // POLLNVAL.
+      }
+      if (revents) nonzero++;
+      {{{ makeSetValue('pollfd', 'members.revents.offset', 'revents', 'i16') }}}
+    }
+    return nonzero;
+  },
+
+  // ==========================================================================
 
   _scanString: function() {
     // Supports %x, %4x, %d.%d, %s
diff --git a/tests/runner.py b/tests/runner.py
index 4a91f59e..99ab9974 100644
--- a/tests/runner.py
+++ b/tests/runner.py
@@ -2210,6 +2210,57 @@ if 'benchmark' not in sys.argv:
       expected = open(path_from_root('tests', 'fcntl-misc', 'output.txt'), 'r').read()
       self.do_test(src, expected, post_build=addPreRun)
 
+    def test_poll(self):
+      def addPreRun(filename):
+        src = open(filename, 'r').read().replace(
+          '// {{PRE_RUN_ADDITIONS}}',
+          '''
+            FS.createDataFile('/', 'file', 'abcdef', true, true);
+            FS.createDevice('/', 'device', function() {}, function() {});
+          '''
+        )
+        open(filename, 'w').write(src)
+      src = r'''
+        #include <stdio.h>
+        #include <errno.h>
+        #include <fcntl.h>
+        #include <poll.h>
+
+        int main() {
+          struct pollfd multi[5];
+          multi[0].fd = open("/file", O_RDONLY, 0777);
+          multi[1].fd = open("/device", O_RDONLY, 0777);
+          multi[2].fd = 123;
+          multi[3].fd = open("/file", O_RDONLY, 0777);
+          multi[4].fd = open("/file", O_RDONLY, 0777);
+          multi[0].events = POLLIN | POLLOUT | POLLNVAL | POLLERR;
+          multi[1].events = POLLIN | POLLOUT | POLLNVAL | POLLERR;
+          multi[2].events = POLLIN | POLLOUT | POLLNVAL | POLLERR;
+          multi[3].events = 0x00;
+          multi[4].events = POLLOUT | POLLNVAL | POLLERR;
+
+          printf("ret: %d\n", poll(multi, 5, 123));
+          printf("errno: %d\n", errno);
+          printf("multi[0].revents: 0x%x\n", multi[0].revents);
+          printf("multi[1].revents: 0x%x\n", multi[1].revents);
+          printf("multi[2].revents: 0x%x\n", multi[2].revents);
+          printf("multi[3].revents: 0x%x\n", multi[3].revents);
+          printf("multi[4].revents: 0x%x\n", multi[4].revents);
+
+          return 0;
+        }
+        '''
+      expected = r'''
+        ret: 4
+        errno: 0
+        multi[0].revents: 0x5
+        multi[1].revents: 0x5
+        multi[2].revents: 0x20
+        multi[3].revents: 0x0
+        multi[4].revents: 0x4
+        '''
+      self.do_test(src, re.sub('(^|\n)\s+', '\\1', expected), post_build=addPreRun)
+
     def test_statvfs(self):
       src = r'''
         #include <stdio.h>