From 1d398369bd5f2bed7c5895cdbe987a4547ae1128 Mon Sep 17 00:00:00 2001
From: Jeff Genovy <29107334+jefgen@users.noreply.github.com>
Date: Thu, 2 Aug 2018 00:09:14 -0700
Subject: [PATCH] ICU-20044 Fix some OOM issues in the NumberFormat class.
 (#21)

---
 icu4c/source/i18n/numfmt.cpp | 50 +++++++++++++++++++-----------------
 1 file changed, 27 insertions(+), 23 deletions(-)

diff --git a/icu4c/source/i18n/numfmt.cpp b/icu4c/source/i18n/numfmt.cpp
index cf0ce6f0ed5..626a5d16fb2 100644
--- a/icu4c/source/i18n/numfmt.cpp
+++ b/icu4c/source/i18n/numfmt.cpp
@@ -1326,13 +1326,13 @@ NumberFormat::makeInstance(const Locale& desiredLocale,
 
         // if the locale has "@compat=host", create a host-specific NumberFormat
         if (U_SUCCESS(status) && count > 0 && uprv_strcmp(buffer, "host") == 0) {
-            Win32NumberFormat *f = NULL;
             UBool curr = TRUE;
 
             switch (style) {
             case UNUM_DECIMAL:
                 curr = FALSE;
                 // fall-through
+                U_FALLTHROUGH;
 
             case UNUM_CURRENCY:
             case UNUM_CURRENCY_ISO: // do not support plural formatting here
@@ -1340,14 +1340,13 @@ NumberFormat::makeInstance(const Locale& desiredLocale,
             case UNUM_CURRENCY_ACCOUNTING:
             case UNUM_CASH_CURRENCY:
             case UNUM_CURRENCY_STANDARD:
-                f = new Win32NumberFormat(desiredLocale, curr, status);
-
+            {
+                LocalPointer<Win32NumberFormat> f(new Win32NumberFormat(desiredLocale, curr, status), status);
                 if (U_SUCCESS(status)) {
-                    return f;
+                    return f.orphan();
                 }
-
-                delete f;
-                break;
+            }
+            break;
             default:
                 break;
             }
@@ -1417,8 +1416,7 @@ NumberFormat::makeInstance(const Locale& desiredLocale,
         }
     }
 
-
-    NumberFormat *f;
+    LocalPointer<NumberFormat> f;
     if (ns->isAlgorithmic()) {
         UnicodeString nsDesc;
         UnicodeString nsRuleSetGroup;
@@ -1453,7 +1451,7 @@ NumberFormat::makeInstance(const Locale& desiredLocale,
             return NULL;
         }
         r->setDefaultRuleSet(nsRuleSetName,status);
-        f = r;
+        f.adoptInstead(r);
     } else {
         // replace single currency sign in the pattern with double currency sign
         // if the style is UNUM_CURRENCY_ISO
@@ -1462,9 +1460,22 @@ NumberFormat::makeInstance(const Locale& desiredLocale,
                                    UnicodeString(TRUE, gDoubleCurrencySign, 2));
         }
 
-        // "new DecimalFormat()" does not adopt the symbols if its memory allocation fails.
-        DecimalFormatSymbols *syms = symbolsToAdopt.orphan();
-        DecimalFormat* df = new DecimalFormat(pattern, syms, style, status);
+        // "new DecimalFormat()" does not adopt the symbols argument if its memory allocation fails.
+        // So we can't use adoptInsteadAndCheckErrorCode as we need to know if the 'new' failed.
+        DecimalFormatSymbols *syms = symbolsToAdopt.getAlias();
+        LocalPointer<DecimalFormat> df(new DecimalFormat(pattern, syms, style, status));
+
+        if (df.isValid()) {
+            // if the DecimalFormat object was successfully new'ed, then it will own symbolsToAdopt, even if the status is a failure.
+            symbolsToAdopt.orphan();
+        }
+        else {
+            status = U_MEMORY_ALLOCATION_ERROR;
+        }
+
+        if (U_FAILURE(status)) {
+            return nullptr;
+        }
 
         // if it is cash currency style, setCurrencyUsage with usage
         if (style == UNUM_CASH_CURRENCY){
@@ -1472,25 +1483,18 @@ NumberFormat::makeInstance(const Locale& desiredLocale,
         }
 
         if (U_FAILURE(status)) {
-            delete df;
-            return NULL;
+            return nullptr;
         }
 
-        f = df;
-        if (f == NULL) {
-            delete syms;
-            status = U_MEMORY_ALLOCATION_ERROR;
-            return NULL;
-        }
+        f.adoptInstead(df.orphan());
     }
 
     f->setLocaleIDs(ures_getLocaleByType(ownedResource.getAlias(), ULOC_VALID_LOCALE, &status),
                     ures_getLocaleByType(ownedResource.getAlias(), ULOC_ACTUAL_LOCALE, &status));
     if (U_FAILURE(status)) {
-        delete f;
         return NULL;
     }
-    return f;
+    return f.orphan();
 }
 
 /**