1 files changed, 39 insertions, 0 deletions
diff --git a/Utilities/cmlibuv/src/unix/core.c b/Utilities/cmlibuv/src/unix/core.c
index 96495b864a..30cdaef7ba 100644
--- a/Utilities/cmlibuv/src/unix/core.c
+++ b/Utilities/cmlibuv/src/unix/core.c
@@ -28,6 +28,7 @@
 #include <errno.h>
 #include <assert.h>
 #include <unistd.h>
+#include <sys/param.h> /* MAXHOSTNAMELEN on Linux and the BSDs */
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <fcntl.h>
@@ -42,6 +43,7 @@
 #include <pwd.h>
 
 #ifdef __sun
+# include <netdb.h> /* MAXHOSTNAMELEN on Solaris */
 # include <sys/filio.h>
 # include <sys/types.h>
 # include <sys/wait.h>
@@ -80,6 +82,11 @@
 #include <sys/ioctl.h>
 #endif
 
+/* Fallback for the maximum hostname length */
+#ifndef MAXHOSTNAMELEN
+# define MAXHOSTNAMELEN 256
+#endif
+
 static int uv__run_pending(uv_loop_t* loop);
 
 /* Verify that uv_buf_t is ABI-compatible with struct iovec. */
@@ -538,6 +545,7 @@ int uv__nonblock_ioctl(int fd, int set) {
 }
 
 
+#if !defined(__CYGWIN__) && !defined(__MSYS__)
 int uv__cloexec_ioctl(int fd, int set) {
   int r;
 
@@ -550,6 +558,7 @@ int uv__cloexec_ioctl(int fd, int set) {
 
   return 0;
 }
+#endif
 
 
 int uv__nonblock_fcntl(int fd, int set) {
@@ -1285,3 +1294,33 @@ int uv_os_unsetenv(const char* name) {
 
   return 0;
 }
+
+
+int uv_os_gethostname(char* buffer, size_t* size) {
+  /*
+    On some platforms, if the input buffer is not large enough, gethostname()
+    succeeds, but truncates the result. libuv can detect this and return ENOBUFS
+    instead by creating a large enough buffer and comparing the hostname length
+    to the size input.
+  */
+  char buf[MAXHOSTNAMELEN + 1];
+  size_t len;
+
+  if (buffer == NULL || size == NULL || *size == 0)
+    return -EINVAL;
+
+  if (gethostname(buf, sizeof(buf)) != 0)
+    return -errno;
+
+  buf[sizeof(buf) - 1] = '\0'; /* Null terminate, just to be safe. */
+  len = strlen(buf);
+
+  if (len >= *size) {
+    *size = len + 1;
+    return -ENOBUFS;
+  }
+
+  memcpy(buffer, buf, len + 1);
+  *size = len;
+  return 0;
+}