From 619c191e442e896d80d23c62b343aee570947ef8 Mon Sep 17 00:00:00 2001
From: roytam1 <roytam@gmail.com>
Date: Fri, 16 Jul 2021 10:38:12 +0800
Subject: [PATCH] import changes from UXP: - [NSPR] Lock access to
 PRCallOnceType members in PR_CallOnce* for thread safety. (361743b22)

---
 nsprpub/pr/src/misc/prinit.c | 46 +++++++++++++++++++++++++-----------
 1 file changed, 32 insertions(+), 14 deletions(-)

diff --git a/nsprpub/pr/src/misc/prinit.c b/nsprpub/pr/src/misc/prinit.c
index 5ac99fe588..a952ad6554 100644
--- a/nsprpub/pr/src/misc/prinit.c
+++ b/nsprpub/pr/src/misc/prinit.c
@@ -771,10 +771,15 @@ PR_IMPLEMENT(PRStatus) PR_CallOnce(
         _PR_ImplicitInitialization();
     }
 
-    if (!once->initialized) {
+    PR_Lock(mod_init.ml);
+    PRIntn initialized = once->initialized;
+    PRStatus status = once->status;
+    PR_Unlock(mod_init.ml);
+    if (!initialized) {
         if (PR_ATOMIC_SET(&once->inProgress, 1) == 0) {
-            once->status = (*func)();
+            status = (*func)();
             PR_Lock(mod_init.ml);
+            once->status = status;
             once->initialized = 1;
             PR_NotifyAllCondVar(mod_init.cv);
             PR_Unlock(mod_init.ml);
@@ -783,14 +788,18 @@ PR_IMPLEMENT(PRStatus) PR_CallOnce(
             while (!once->initialized) {
                 PR_WaitCondVar(mod_init.cv, PR_INTERVAL_NO_TIMEOUT);
             }
+            status = once->status;
             PR_Unlock(mod_init.ml);
+            if (PR_SUCCESS != status) {
+                PR_SetError(PR_CALL_ONCE_ERROR, 0);
+            }
         }
-    } else {
-        if (PR_SUCCESS != once->status) {
-            PR_SetError(PR_CALL_ONCE_ERROR, 0);
-        }
+        return status;
     }
-    return once->status;
+    if (PR_SUCCESS != status) {
+        PR_SetError(PR_CALL_ONCE_ERROR, 0);
+    }
+    return status;
 }
 
 PR_IMPLEMENT(PRStatus) PR_CallOnceWithArg(
@@ -802,10 +811,15 @@ PR_IMPLEMENT(PRStatus) PR_CallOnceWithArg(
         _PR_ImplicitInitialization();
     }
 
-    if (!once->initialized) {
+    PR_Lock(mod_init.ml);
+    PRIntn initialized = once->initialized;
+    PRStatus status = once->status;
+    PR_Unlock(mod_init.ml);
+    if (!initialized) {
         if (PR_ATOMIC_SET(&once->inProgress, 1) == 0) {
-            once->status = (*func)(arg);
+            status = (*func)(arg);
             PR_Lock(mod_init.ml);
+            once->status = status;
             once->initialized = 1;
             PR_NotifyAllCondVar(mod_init.cv);
             PR_Unlock(mod_init.ml);
@@ -814,14 +828,18 @@ PR_IMPLEMENT(PRStatus) PR_CallOnceWithArg(
             while (!once->initialized) {
                 PR_WaitCondVar(mod_init.cv, PR_INTERVAL_NO_TIMEOUT);
             }
+            status = once->status;
             PR_Unlock(mod_init.ml);
+            if (PR_SUCCESS != status) {
+                PR_SetError(PR_CALL_ONCE_ERROR, 0);
+            }
         }
-    } else {
-        if (PR_SUCCESS != once->status) {
-            PR_SetError(PR_CALL_ONCE_ERROR, 0);
-        }
+        return status;
     }
-    return once->status;
+    if (PR_SUCCESS != status) {
+        PR_SetError(PR_CALL_ONCE_ERROR, 0);
+    }
+    return status;
 }
 
 PRBool _PR_Obsolete(const char *obsolete, const char *preferred)