Bug 1420677 - Convert nsHostResolver.addr_info to a UniquePtr. r=valentin

MozReview-Commit-ID: 4zX73VhxiKe

netwerk/dns/GetAddrInfo.cpp

@@ -251,10 +251,9 @@ _GetTTLData_Windows(const char* aHost, uint32_t* aResult, uint16_t aAddressFamil
 static MOZ_ALWAYS_INLINE nsresult
 _GetAddrInfo_Portable(const char* aCanonHost, uint16_t aAddressFamily,
                       uint16_t aFlags, const char* aNetworkInterface,
-                      AddrInfo** aAddrInfo)
+                      UniquePtr<AddrInfo>& aAddrInfo)
 {
   MOZ_ASSERT(aCanonHost);
-  MOZ_ASSERT(aAddrInfo);
 
   // We accept the same aFlags that nsHostResolver::ResolveHost accepts, but we
   // need to translate the aFlags into a form that PR_GetAddrInfoByName
@@ -283,14 +282,14 @@ _GetAddrInfo_Portable(const char* aCanonHost, uint16_t aAddressFamily,
   }
 
   bool filterNameCollision = !(aFlags & nsHostResolver::RES_ALLOW_NAME_COLLISION);
-  nsAutoPtr<AddrInfo> ai(new AddrInfo(aCanonHost, prai, disableIPv4,
-                                      filterNameCollision, canonName));
+  auto ai = MakeUnique<AddrInfo>(aCanonHost, prai, disableIPv4,
+                                 filterNameCollision, canonName);
   PR_FreeAddrInfo(prai);
   if (ai->mAddresses.isEmpty()) {
     return NS_ERROR_UNKNOWN_HOST;
   }
 
-  *aAddrInfo = ai.forget();
+  aAddrInfo = Move(ai);
 
   return NS_OK;
 }
@@ -322,9 +321,10 @@ GetAddrInfoShutdown() {
 
 nsresult
 GetAddrInfo(const char* aHost, uint16_t aAddressFamily, uint16_t aFlags,
-            const char* aNetworkInterface, AddrInfo** aAddrInfo, bool aGetTtl)
+            const char* aNetworkInterface,
+            UniquePtr<AddrInfo>& aAddrInfo, bool aGetTtl)
 {
-  if (NS_WARN_IF(!aHost) || NS_WARN_IF(!aAddrInfo)) {
+  if (NS_WARN_IF(!aHost)) {
     return NS_ERROR_NULL_POINTER;
   }
 
@@ -335,7 +335,7 @@ GetAddrInfo(const char* aHost, uint16_t aAddressFamily, uint16_t aFlags,
   }
 #endif
 
-  *aAddrInfo = nullptr;
+  aAddrInfo = nullptr;
   nsresult rv = _GetAddrInfo_Portable(aHost, aAddressFamily, aFlags,
                                       aNetworkInterface, aAddrInfo);
 
@@ -344,8 +344,8 @@ GetAddrInfo(const char* aHost, uint16_t aAddressFamily, uint16_t aFlags,
     // Figure out the canonical name, or if that fails, just use the host name
     // we have.
     const char *name = nullptr;
-    if (*aAddrInfo != nullptr && (*aAddrInfo)->mCanonicalName) {
-      name = (*aAddrInfo)->mCanonicalName;
+    if (aAddrInfo && aAddrInfo->mCanonicalName) {
+      name = aAddrInfo->mCanonicalName;
     } else {
       name = aHost;
     }
@@ -354,7 +354,7 @@ GetAddrInfo(const char* aHost, uint16_t aAddressFamily, uint16_t aFlags,
     uint32_t ttl = 0;
     nsresult ttlRv = _GetTTLData_Windows(name, &ttl, aAddressFamily);
     if (NS_SUCCEEDED(ttlRv)) {
-      (*aAddrInfo)->ttl = ttl;
+      aAddrInfo->ttl = ttl;
       LOG("Got TTL %u for %s (name = %s).", ttl, aHost, name);
     } else {
       LOG_WARNING("Could not get TTL for %s (cname = %s).", aHost, name);

netwerk/dns/GetAddrInfo.h

@@ -40,7 +40,8 @@ class AddrInfo;
  */
 nsresult
 GetAddrInfo(const char* aHost, uint16_t aAddressFamily, uint16_t aFlags,
-            const char* aNetworkInterface, AddrInfo** aAddrInfo, bool aGetTtl);
+            const char* aNetworkInterface,
+            UniquePtr<AddrInfo>& aAddrInfo, bool aGetTtl);
 
 /**
  * Initialize the GetAddrInfo module.

netwerk/dns/nsHostResolver.cpp

@@ -231,7 +231,6 @@ nsHostRecord::CopyExpirationTimesAndFlagsFrom(const nsHostRecord *aFromHostRecor
 nsHostRecord::~nsHostRecord()
 {
     Telemetry::Accumulate(Telemetry::DNS_BLACKLIST_COUNT, mBlacklistedCount);
-    delete addr_info;
 }
 
 bool
@@ -599,7 +598,8 @@ nsHostResolver::ClearPendingQueue(PRCList *aPendingQ)
         while (node != aPendingQ) {
             nsHostRecord *rec = static_cast<nsHostRecord *>(node);
             node = node->next;
-            OnLookupComplete(rec, NS_ERROR_ABORT, nullptr);
+            OnLookupComplete(rec, NS_ERROR_ABORT,
+                             mozilla::UniquePtr<AddrInfo>(nullptr));
         }
     }
 }
@@ -880,7 +880,7 @@ nsHostResolver::ResolveHost(const char             *host,
                                 if ((af == addrIter->mAddress.inet.family) &&
                                      !unspecHe->rec->Blacklisted(&addrIter->mAddress)) {
                                     if (!he->rec->addr_info) {
-                                        he->rec->addr_info = new AddrInfo(
+                                        he->rec->addr_info = mozilla::MakeUnique<AddrInfo>(
                                             unspecHe->rec->addr_info->mHostName,
                                             unspecHe->rec->addr_info->mCanonicalName);
                                         he->rec->CopyExpirationTimesAndFlagsFrom(unspecHe->rec);
@@ -1282,7 +1282,8 @@ different_rrset(AddrInfo *rrset1, AddrInfo *rrset2)
 // returns LOOKUP_RESOLVEAGAIN, but only if 'status' is not NS_ERROR_ABORT.
 // takes ownership of AddrInfo parameter
 nsHostResolver::LookupStatus
-nsHostResolver::OnLookupComplete(nsHostRecord* rec, nsresult status, AddrInfo* newRRSet)
+nsHostResolver::OnLookupComplete(nsHostRecord* rec, nsresult status,
+                                 mozilla::UniquePtr<AddrInfo>&& newRRSet)
 {
     // get the list of pending callbacks for this lookup, and notify
     // them that the lookup is complete.
@@ -1294,7 +1295,6 @@ nsHostResolver::OnLookupComplete(nsHostRecord* rec, nsresult status, AddrInfo* n
         if (rec->mResolveAgain && (status != NS_ERROR_ABORT)) {
             LOG(("nsHostResolver record %p resolve again due to flushcache\n", rec));
             rec->mResolveAgain = false;
-            delete newRRSet;
             return LOOKUP_RESOLVEAGAIN;
         }
 
@@ -1303,22 +1303,18 @@ nsHostResolver::OnLookupComplete(nsHostRecord* rec, nsresult status, AddrInfo* n
 
         // update record fields.  We might have a rec->addr_info already if a
         // previous lookup result expired and we're reresolving it..
-        AddrInfo  *old_addr_info;
         {
             MutexAutoLock lock(rec->addr_info_lock);
-            if (different_rrset(rec->addr_info, newRRSet)) {
+            if (different_rrset(rec->addr_info.get(), newRRSet.get())) {
                 LOG(("nsHostResolver record %p new gencnt\n", rec));
-                old_addr_info = rec->addr_info;
-                rec->addr_info = newRRSet;
+                rec->addr_info = Move(newRRSet);
                 rec->addr_info_gencnt++;
             } else {
                 if (rec->addr_info && newRRSet) {
                     rec->addr_info->ttl = newRRSet->ttl;
                 }
-                old_addr_info = newRRSet;
             }
         }
-        delete old_addr_info;
 
         rec->negative = !rec->addr_info;
         PrepareRecordExpiration(rec);
@@ -1468,7 +1464,7 @@ nsHostResolver::ThreadFunc(void *arg)
 #endif
     nsHostResolver *resolver = (nsHostResolver *)arg;
     nsHostRecord *rec  = nullptr;
-    AddrInfo *ai = nullptr;
+    mozilla::UniquePtr<AddrInfo> ai = nullptr;
 
     while (rec || resolver->GetHostToLookup(&rec)) {
         LOG(("DNS lookup thread - Calling getaddrinfo for host [%s%s%s].\n",
@@ -1482,10 +1478,10 @@ nsHostResolver::ThreadFunc(void *arg)
 #endif
 
         nsresult status = GetAddrInfo(rec->host, rec->af, rec->flags, rec->netInterface,
-                                      &ai, getTtl);
+                                      ai, getTtl);
 #if defined(RES_RETRY_ON_FAILURE)
         if (NS_FAILED(status) && rs.Reset()) {
-            status = GetAddrInfo(rec->host, rec->af, rec->flags, rec->netInterface, &ai,
+            status = GetAddrInfo(rec->host, rec->af, rec->flags, rec->netInterface, ai,
                                  getTtl);
         }
 #endif
@@ -1521,7 +1517,8 @@ nsHostResolver::ThreadFunc(void *arg)
              LOG_HOST(rec->host, rec->netInterface),
              ai ? "success" : "failure: unknown host"));
 
-        if (LOOKUP_RESOLVEAGAIN == resolver->OnLookupComplete(rec, status, ai)) {
+        if (LOOKUP_RESOLVEAGAIN == resolver->OnLookupComplete(rec, status,
+                                                              mozilla::Move(ai))) {
             // leave 'rec' assigned and loop to make a renewed host resolve
             LOG(("DNS lookup thread - Re-resolving host [%s%s%s].\n",
                  LOG_HOST(rec->host, rec->netInterface)));

netwerk/dns/nsHostResolver.h

@@ -75,7 +75,7 @@ public:
      */
     Mutex        addr_info_lock;
     int          addr_info_gencnt; /* generation count of |addr_info| */
-    mozilla::net::AddrInfo *addr_info;
+    mozilla::UniquePtr<mozilla::net::AddrInfo> addr_info;
     mozilla::UniquePtr<mozilla::net::NetAddr> addr;
     bool         negative;   /* True if this record is a cache of a failed lookup.
                                 Negative cache entries are valid just like any other
@@ -318,7 +318,8 @@ private:
       LOOKUP_RESOLVEAGAIN,
     };
 
-    LookupStatus OnLookupComplete(nsHostRecord *, nsresult, mozilla::net::AddrInfo *);
+    LookupStatus OnLookupComplete(nsHostRecord *, nsresult,
+                                  mozilla::UniquePtr<mozilla::net::AddrInfo>&&);
     void     DeQueue(PRCList &aQ, nsHostRecord **aResult);
     void     ClearPendingQueue(PRCList *aPendingQueue);
     nsresult ConditionallyCreateThread(nsHostRecord *rec);