1 files changed, 47 insertions, 16 deletions

diff --git a/thirdparty/icu4c/common/uresimp.h b/thirdparty/icu4c/common/uresimp.h
index f038dedace..4ac09bd8c4 100644
--- a/thirdparty/icu4c/common/uresimp.h
+++ b/thirdparty/icu4c/common/uresimp.h
@@ -31,7 +31,6 @@
 #define MAGIC2 19641227
 
 #define URES_MAX_ALIAS_LEVEL 256
-#define URES_MAX_BUFFER_SIZE 256
 
 #define EMPTY_SET 0x2205
 
@@ -61,16 +60,27 @@ struct UResourceDataEntry {
 #define RES_PATH_SEPARATOR   '/'
 #define RES_PATH_SEPARATOR_S   "/"
 
+U_CAPI void U_EXPORT2 ures_initStackObject(UResourceBundle* resB);
+
+#ifdef __cplusplus
+
 struct UResourceBundle {
     const char *fKey; /*tag*/
+    /**
+     * The dataEntry for the actual locale in which this item lives.
+     * Used for accessing the item's data.
+     * Non-const pointer for reference counting via entryIncrease().
+     */
     UResourceDataEntry *fData; /*for low-level access*/
     char *fVersion;
-    UResourceDataEntry *fTopLevelData; /* for getting the valid locale */
+    /**
+     * The dataEntry for the valid locale.
+     * Used for /LOCALE/path alias resolution that starts back from the valid locale,
+     * rather than from the actual locale of this item which might live in
+     * an ancestor bundle.
+     */
+    UResourceDataEntry *fValidLocaleDataEntry;
     char *fResPath; /* full path to the resource: "zh_TW/CollationElements/Sequence" */
-    // TODO(ICU-20769): Try to change the by-value fResData into a pointer,
-    // with the struct in only one place for each bundle.
-    // Also replace class ResourceDataValue.resData with a pResData pointer again.
-    ResourceData fResData;
     char fResBuf[RES_BUFSIZE];
     int32_t fResPathLen;
     Resource fRes;
@@ -81,13 +91,9 @@ struct UResourceBundle {
     int32_t fIndex;
     int32_t fSize;
 
-    /*const UResourceBundle *fParentRes;*/ /* needed to get the actual locale for a child resource */
+    inline const ResourceData &getResData() const { return fData->fData; }
 };
 
-U_CAPI void U_EXPORT2 ures_initStackObject(UResourceBundle* resB);
-
-#ifdef __cplusplus
-
 U_NAMESPACE_BEGIN
 
 /**
@@ -161,9 +167,6 @@ U_CFUNC const char* ures_getPath(const UResourceBundle* resB);
  */
 U_CAPI UBool U_EXPORT2 ures_dumpCacheContents(void);
 #endif
-/*U_CFUNC void ures_appendResPath(UResourceBundle *resB, const char* toAdd, int32_t lenToAdd);*/
-/*U_CFUNC void ures_setResPath(UResourceBundle *resB, const char* toAdd);*/
-/*U_CFUNC void ures_freeResPath(UResourceBundle *resB);*/
 
 /* Candidates for export */
 U_CFUNC UResourceBundle *ures_copyResb(UResourceBundle *r, const UResourceBundle *original, UErrorCode *status);
@@ -261,7 +264,6 @@ ures_getByKeyWithFallback(const UResourceBundle *resB,
                           UResourceBundle *fillIn, 
                           UErrorCode *status);
 
-
 /**
  * Get a String with multi-level fallback. Normally only the top level resources will
  * fallback to its parent. This performs fallback on subresources. For example, when a table
@@ -291,10 +293,39 @@ ures_getValueWithFallback(const UResourceBundle *bundle, const char *path,
                           UResourceBundle *tempFillIn,
                           icu::ResourceDataValue &value, UErrorCode &errorCode);
 
+/**
+ * Locates the resource specified by `path` in the resource bundle specified by `bundle` (performing any
+ * necessary fallback and following any aliases) and calls the specified `sink`'s `put()` method with that
+ * resource.  Then walks the bundle's parent chain, calling `put()` on the sink for each item in the
+ * parent chain.
+ * @param bundle The bundle to search
+ * @param path The path of the desired resource
+ * @param sink A `ResourceSink` that gets called for each resource in the parent chain
+ * @param errorCode The error code
+ */
 U_CAPI void U_EXPORT2
 ures_getAllItemsWithFallback(const UResourceBundle *bundle, const char *path,
                              icu::ResourceSink &sink, UErrorCode &errorCode);
 
+/**
+ * Locates the resource specified by `path` in the resource bundle specified by `bundle` (performing any
+ * necessary fallback and following any aliases) and, if the resource is a table resource, iterates over its
+ * immediate child resources (again, following any aliases to get the individual resource values), and calls the specified
+ * `sink`'s `put()` method for each child resource (passing it that resource's key and either its actual value or,
+ * if that value is an alias, the value you get by following the alias).  Then walks back over the bundle's
+ * parent chain, similarly iterating over each parent table resource's child resources.
+ * Does not descend beyond one level of table children.
+ * @param bundle The bundle to search
+ * @param path The path of the desired resource
+ * @param sink A `ResourceSink` that gets called for each child resource of the specified resource (and each child
+ * of the resources in its parent chain).
+ * @param errorCode The error code.  This will be U_RESOURCE_TYPE_MISMATCH if the resource the caller
+ * is asking for isn't a table resource.
+ */
+U_CAPI void U_EXPORT2
+ures_getAllChildrenWithFallback(const UResourceBundle *bundle, const char *path,
+                                icu::ResourceSink &sink, UErrorCode &errorCode);
+
 #endif  /* __cplusplus */
 
 /**
@@ -328,7 +359,7 @@ ures_getVersionNumberInternal(const UResourceBundle *resourceBundle);
  * you to query for the real locale of the resource. For example, if you requested 
  * "en_US_CALIFORNIA" and only "en_US" bundle exists, "en_US" will be returned. 
  * For subresources, the locale where this resource comes from will be returned.
- * If fallback has occured, getLocale will reflect this.
+ * If fallback has occurred, getLocale will reflect this.
  *
  * This internal version avoids deprecated-warnings in ICU code.
  *