Merge pull request #334 from astrangeguy/1.11

make reserve_tls_slots() more lenient (fixes #311)

lisp-kernel/windows-calls.c

@@ -1028,30 +1028,31 @@ init_winsock()
 void
 reserve_tls_slots()
 {
-  unsigned int first_available, n, i;
+  unsigned int last_slot, i, cnt_pad;
+  unsigned int pad_slots[30];
+
+  /* Since there is no way to reserve specific TLS indices, we reserve
+   * indices upto 30, hope to reserve 30 to 63 in one continuous block
+   * and then free those below 30.
+   */
+  cnt_pad = 0;
+  do {
+    last_slot = TlsAlloc();
+    pad_slots[cnt_pad++] = last_slot;
+  } while (last_slot < 30 && cnt_pad < 30);
 
-  first_available = TlsAlloc();
-  if (first_available > 30) {
-    fprintf(dbgout, "Can't allocate required TLS indexes.\n");
-    fprintf(dbgout, "First available index value was %u\n", first_available);
+  if (last_slot != 30) {
+    fprintf(dbgout, "could not reserve TLS slots from 30 to 63: Slot %u already reserved\n", 30);
     exit(1);
   }
-  TlsFree(first_available);
-
-  for (i = first_available; i < 30; i++) {
-    n = TlsAlloc();
-    if (n != i) {
-      fprintf(dbgout, "unexpected TLS index value: wanted %u, got %u\n", i, n);
-      exit(1);
-    }
-  }
-  for (i = 30; i < 64; i++) {
-    n = TlsAlloc();
-    if (n != i) {
-      fprintf(dbgout, "unexpected TLS index value: wanted %u, got %u\n", i, n);
+  for (i = 31; i < 64; i++) {
+    last_slot = TlsAlloc();
+    if (last_slot != i) {
+      fprintf(dbgout, "could not reserve TLS slots from 30 to 63: Slot %u already reserved\n", i);
       exit(1);
     }
   }
-  for (i = first_available; i < 30; i++)
-    TlsFree(i);
+  for (i = 0; i < cnt_pad; i++)
+    if (pad_slots[i] < 30)
+      TlsFree(pad_slots[i]);
 }