--- /dev/null
+// © 2019 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html#License
+
+// localeprioritylist.cpp
+// created: 2019jul11 Markus W. Scherer
+
+#include "unicode/utypes.h"
+#include "unicode/localpointer.h"
+#include "unicode/locid.h"
+#include "unicode/stringpiece.h"
+#include "unicode/uobject.h"
+#include "charstr.h"
+#include "cmemory.h"
+#include "localeprioritylist.h"
+#include "uarrsort.h"
+#include "uassert.h"
+#include "uhash.h"
+
+U_NAMESPACE_BEGIN
+
+namespace {
+
+int32_t hashLocale(const UHashTok token) {
+ auto *locale = static_cast<const Locale *>(token.pointer);
+ return locale->hashCode();
+}
+
+UBool compareLocales(const UHashTok t1, const UHashTok t2) {
+ auto *l1 = static_cast<const Locale *>(t1.pointer);
+ auto *l2 = static_cast<const Locale *>(t2.pointer);
+ return *l1 == *l2;
+}
+
+constexpr int32_t WEIGHT_ONE = 1000;
+
+struct LocaleAndWeight {
+ Locale *locale;
+ int32_t weight; // 0..1000 = 0.0..1.0
+ int32_t index; // force stable sort
+
+ int32_t compare(const LocaleAndWeight &other) const {
+ int32_t diff = other.weight - weight; // descending: other-this
+ if (diff != 0) { return diff; }
+ return index - other.index;
+ }
+};
+
+int32_t U_CALLCONV
+compareLocaleAndWeight(const void * /*context*/, const void *left, const void *right) {
+ return static_cast<const LocaleAndWeight *>(left)->
+ compare(*static_cast<const LocaleAndWeight *>(right));
+}
+
+const char *skipSpaces(const char *p, const char *limit) {
+ while (p < limit && *p == ' ') { ++p; }
+ return p;
+}
+
+int32_t findTagLength(const char *p, const char *limit) {
+ // Look for accept-language delimiters.
+ // Leave other validation up to the Locale constructor.
+ const char *q;
+ for (q = p; q < limit; ++q) {
+ char c = *q;
+ if (c == ' ' || c == ',' || c == ';') { break; }
+ }
+ return static_cast<int32_t>(q - p);
+}
+
+/**
+ * Parses and returns a qvalue weight in millis.
+ * Advances p to after the parsed substring.
+ * Returns a negative value if parsing fails.
+ */
+int32_t parseWeight(const char *&p, const char *limit) {
+ p = skipSpaces(p, limit);
+ char c;
+ if (p == limit || ((c = *p) != '0' && c != '1')) { return -1; }
+ int32_t weight = (c - '0') * 1000;
+ if (++p == limit || *p != '.') { return weight; }
+ int32_t multiplier = 100;
+ while (++p != limit && '0' <= (c = *p) && c <= '9') {
+ c -= '0';
+ if (multiplier > 0) {
+ weight += c * multiplier;
+ multiplier /= 10;
+ } else if (multiplier == 0) {
+ // round up
+ if (c >= 5) { ++weight; }
+ multiplier = -1;
+ } // else ignore further fraction digits
+ }
+ return weight <= WEIGHT_ONE ? weight : -1; // bad if > 1.0
+}
+
+} // namespace
+
+/**
+ * Nothing but a wrapper over a MaybeStackArray of LocaleAndWeight.
+ *
+ * This wrapper exists (and is not in an anonymous namespace)
+ * so that we can forward-declare it in the header file and
+ * don't have to expose the MaybeStackArray specialization and
+ * the LocaleAndWeight to code (like the test) that #includes localeprioritylist.h.
+ * Also, otherwise we would have to do a platform-specific
+ * template export declaration of some kind for the MaybeStackArray specialization
+ * to be properly exported from the common DLL.
+ */
+struct LocaleAndWeightArray : public UMemory {
+ MaybeStackArray<LocaleAndWeight, 20> array;
+};
+
+LocalePriorityList::LocalePriorityList(StringPiece s, UErrorCode &errorCode) {
+ if (U_FAILURE(errorCode)) { return; }
+ list = new LocaleAndWeightArray();
+ if (list == nullptr) {
+ errorCode = U_MEMORY_ALLOCATION_ERROR;
+ return;
+ }
+ const char *p = s.data();
+ const char *limit = p + s.length();
+ while ((p = skipSpaces(p, limit)) != limit) {
+ if (*p == ',') { // empty range field
+ ++p;
+ continue;
+ }
+ int32_t tagLength = findTagLength(p, limit);
+ if (tagLength == 0) {
+ errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+ return;
+ }
+ CharString tag(p, tagLength, errorCode);
+ if (U_FAILURE(errorCode)) { return; }
+ Locale locale = Locale(tag.data());
+ if (locale.isBogus()) {
+ errorCode = U_MEMORY_ALLOCATION_ERROR;
+ return;
+ }
+ int32_t weight = WEIGHT_ONE;
+ if ((p = skipSpaces(p + tagLength, limit)) != limit && *p == ';') {
+ if ((p = skipSpaces(p + 1, limit)) == limit || *p != 'q' ||
+ (p = skipSpaces(p + 1, limit)) == limit || *p != '=' ||
+ (++p, (weight = parseWeight(p, limit)) < 0)) {
+ errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+ return;
+ }
+ p = skipSpaces(p, limit);
+ }
+ if (p != limit && *p != ',') { // trailing junk
+ errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+ return;
+ }
+ add(locale, weight, errorCode);
+ if (p == limit) { break; }
+ ++p;
+ }
+ sort(errorCode);
+}
+
+LocalePriorityList::~LocalePriorityList() {
+ if (list != nullptr) {
+ for (int32_t i = 0; i < listLength; ++i) {
+ delete list->array[i].locale;
+ }
+ delete list;
+ }
+ uhash_close(map);
+}
+
+const Locale *LocalePriorityList::localeAt(int32_t i) const {
+ return list->array[i].locale;
+}
+
+Locale *LocalePriorityList::orphanLocaleAt(int32_t i) {
+ if (list == nullptr) { return nullptr; }
+ LocaleAndWeight &lw = list->array[i];
+ Locale *l = lw.locale;
+ lw.locale = nullptr;
+ return l;
+}
+
+bool LocalePriorityList::add(const Locale &locale, int32_t weight, UErrorCode &errorCode) {
+ if (U_FAILURE(errorCode)) { return false; }
+ if (map == nullptr) {
+ if (weight <= 0) { return true; } // do not add q=0
+ map = uhash_open(hashLocale, compareLocales, uhash_compareLong, &errorCode);
+ if (U_FAILURE(errorCode)) { return false; }
+ }
+ LocalPointer<Locale> clone;
+ int32_t index = uhash_geti(map, &locale);
+ if (index != 0) {
+ // Duplicate: Remove the old item and append it anew.
+ LocaleAndWeight &lw = list->array[index - 1];
+ clone.adoptInstead(lw.locale);
+ lw.locale = nullptr;
+ lw.weight = 0;
+ ++numRemoved;
+ }
+ if (weight <= 0) { // do not add q=0
+ if (index != 0) {
+ // Not strictly necessary but cleaner.
+ uhash_removei(map, &locale);
+ }
+ return true;
+ }
+ if (clone.isNull()) {
+ clone.adoptInstead(locale.clone());
+ if (clone.isNull() || (clone->isBogus() && !locale.isBogus())) {
+ errorCode = U_MEMORY_ALLOCATION_ERROR;
+ return false;
+ }
+ }
+ if (listLength == list->array.getCapacity()) {
+ int32_t newCapacity = listLength < 50 ? 100 : 4 * listLength;
+ if (list->array.resize(newCapacity, listLength) == nullptr) {
+ errorCode = U_MEMORY_ALLOCATION_ERROR;
+ return false;
+ }
+ }
+ uhash_puti(map, clone.getAlias(), listLength + 1, &errorCode);
+ if (U_FAILURE(errorCode)) { return false; }
+ LocaleAndWeight &lw = list->array[listLength];
+ lw.locale = clone.orphan();
+ lw.weight = weight;
+ lw.index = listLength++;
+ if (weight < WEIGHT_ONE) { hasWeights = true; }
+ U_ASSERT(uhash_count(map) == getLength());
+ return true;
+}
+
+void LocalePriorityList::sort(UErrorCode &errorCode) {
+ // Sort by descending weights if there is a mix of weights.
+ // The comparator forces a stable sort via the item index.
+ if (U_FAILURE(errorCode) || getLength() <= 1 || !hasWeights) { return; }
+ uprv_sortArray(list->array.getAlias(), listLength, sizeof(LocaleAndWeight),
+ compareLocaleAndWeight, nullptr, FALSE, &errorCode);
+}
+
+U_NAMESPACE_END
projects / apple / icu.git / blobdiff