initial commit, 4.5 stable

thirdparty/icu4c/common/simpleformatter.cpp

@@ -0,0 +1,325 @@
+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+******************************************************************************
+* Copyright (C) 2014-2016, International Business Machines
+* Corporation and others.  All Rights Reserved.
+******************************************************************************
+* simpleformatter.cpp
+*/
+
+#include "unicode/utypes.h"
+#include "unicode/simpleformatter.h"
+#include "unicode/unistr.h"
+#include "uassert.h"
+
+U_NAMESPACE_BEGIN
+
+namespace {
+
+/**
+ * Argument numbers must be smaller than this limit.
+ * Text segment lengths are offset by this much.
+ * This is currently the only unused char value in compiled patterns,
+ * except it is the maximum value of the first unit (max arg +1).
+ */
+const int32_t ARG_NUM_LIMIT = 0x100;
+/**
+ * Initial and maximum char/char16_t value set for a text segment.
+ * Segment length char values are from ARG_NUM_LIMIT+1 to this value here.
+ * Normally 0xffff, but can be as small as ARG_NUM_LIMIT+1 for testing.
+ */
+const char16_t SEGMENT_LENGTH_PLACEHOLDER_CHAR = 0xffff;
+/**
+ * Maximum length of a text segment. Longer segments are split into shorter ones.
+ */
+const int32_t MAX_SEGMENT_LENGTH = SEGMENT_LENGTH_PLACEHOLDER_CHAR - ARG_NUM_LIMIT;
+
+enum {
+    APOS = 0x27,
+    DIGIT_ZERO = 0x30,
+    DIGIT_ONE = 0x31,
+    DIGIT_NINE = 0x39,
+    OPEN_BRACE = 0x7b,
+    CLOSE_BRACE = 0x7d
+};
+
+inline UBool isInvalidArray(const void *array, int32_t length) {
+   return (length < 0 || (array == nullptr && length != 0));
+}
+
+}  // namespace
+
+SimpleFormatter &SimpleFormatter::operator=(const SimpleFormatter& other) {
+    if (this == &other) {
+        return *this;
+    }
+    compiledPattern = other.compiledPattern;
+    return *this;
+}
+
+SimpleFormatter::~SimpleFormatter() {}
+
+UBool SimpleFormatter::applyPatternMinMaxArguments(
+        const UnicodeString &pattern,
+        int32_t min, int32_t max,
+        UErrorCode &errorCode) {
+    if (U_FAILURE(errorCode)) {
+        return false;
+    }
+    // Parse consistent with MessagePattern, but
+    // - support only simple numbered arguments
+    // - build a simple binary structure into the result string
+    const char16_t *patternBuffer = pattern.getBuffer();
+    int32_t patternLength = pattern.length();
+    // Reserve the first char for the number of arguments.
+    compiledPattern.setTo(static_cast<char16_t>(0));
+    int32_t textLength = 0;
+    int32_t maxArg = -1;
+    UBool inQuote = false;
+    for (int32_t i = 0; i < patternLength;) {
+        char16_t c = patternBuffer[i++];
+        if (c == APOS) {
+            if (i < patternLength && (c = patternBuffer[i]) == APOS) {
+                // double apostrophe, skip the second one
+                ++i;
+            } else if (inQuote) {
+                // skip the quote-ending apostrophe
+                inQuote = false;
+                continue;
+            } else if (c == OPEN_BRACE || c == CLOSE_BRACE) {
+                // Skip the quote-starting apostrophe, find the end of the quoted literal text.
+                ++i;
+                inQuote = true;
+            } else {
+                // The apostrophe is part of literal text.
+                c = APOS;
+            }
+        } else if (!inQuote && c == OPEN_BRACE) {
+            if (textLength > 0) {
+                compiledPattern.setCharAt(compiledPattern.length() - textLength - 1,
+                                          static_cast<char16_t>(ARG_NUM_LIMIT + textLength));
+                textLength = 0;
+            }
+            int32_t argNumber;
+            if ((i + 1) < patternLength &&
+                    0 <= (argNumber = patternBuffer[i] - DIGIT_ZERO) && argNumber <= 9 &&
+                    patternBuffer[i + 1] == CLOSE_BRACE) {
+                i += 2;
+            } else {
+                // Multi-digit argument number (no leading zero) or syntax error.
+                // MessagePattern permits PatternProps.skipWhiteSpace(pattern, index)
+                // around the number, but this class does not.
+                argNumber = -1;
+                if (i < patternLength && DIGIT_ONE <= (c = patternBuffer[i++]) && c <= DIGIT_NINE) {
+                    argNumber = c - DIGIT_ZERO;
+                    while (i < patternLength &&
+                            DIGIT_ZERO <= (c = patternBuffer[i++]) && c <= DIGIT_NINE) {
+                        argNumber = argNumber * 10 + (c - DIGIT_ZERO);
+                        if (argNumber >= ARG_NUM_LIMIT) {
+                            break;
+                        }
+                    }
+                }
+                if (argNumber < 0 || c != CLOSE_BRACE) {
+                    errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+                    return false;
+                }
+            }
+            if (argNumber > maxArg) {
+                maxArg = argNumber;
+            }
+            compiledPattern.append(static_cast<char16_t>(argNumber));
+            continue;
+        }  // else: c is part of literal text
+        // Append c and track the literal-text segment length.
+        if (textLength == 0) {
+            // Reserve a char for the length of a new text segment, preset the maximum length.
+            compiledPattern.append(SEGMENT_LENGTH_PLACEHOLDER_CHAR);
+        }
+        compiledPattern.append(c);
+        if (++textLength == MAX_SEGMENT_LENGTH) {
+            textLength = 0;
+        }
+    }
+    if (textLength > 0) {
+        compiledPattern.setCharAt(compiledPattern.length() - textLength - 1,
+                                  static_cast<char16_t>(ARG_NUM_LIMIT + textLength));
+    }
+    int32_t argCount = maxArg + 1;
+    if (argCount < min || max < argCount) {
+        errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+        return false;
+    }
+    compiledPattern.setCharAt(0, static_cast<char16_t>(argCount));
+    return true;
+}
+
+UnicodeString& SimpleFormatter::format(
+        const UnicodeString &value0,
+        UnicodeString &appendTo, UErrorCode &errorCode) const {
+    const UnicodeString *values[] = { &value0 };
+    return formatAndAppend(values, 1, appendTo, nullptr, 0, errorCode);
+}
+
+UnicodeString& SimpleFormatter::format(
+        const UnicodeString &value0,
+        const UnicodeString &value1,
+        UnicodeString &appendTo, UErrorCode &errorCode) const {
+    const UnicodeString *values[] = { &value0, &value1 };
+    return formatAndAppend(values, 2, appendTo, nullptr, 0, errorCode);
+}
+
+UnicodeString& SimpleFormatter::format(
+        const UnicodeString &value0,
+        const UnicodeString &value1,
+        const UnicodeString &value2,
+        UnicodeString &appendTo, UErrorCode &errorCode) const {
+    const UnicodeString *values[] = { &value0, &value1, &value2 };
+    return formatAndAppend(values, 3, appendTo, nullptr, 0, errorCode);
+}
+
+UnicodeString& SimpleFormatter::formatAndAppend(
+        const UnicodeString *const *values, int32_t valuesLength,
+        UnicodeString &appendTo,
+        int32_t *offsets, int32_t offsetsLength, UErrorCode &errorCode) const {
+    if (U_FAILURE(errorCode)) {
+        return appendTo;
+    }
+    if (isInvalidArray(values, valuesLength) || isInvalidArray(offsets, offsetsLength) ||
+            valuesLength < getArgumentLimit()) {
+        errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+        return appendTo;
+    }
+    return format(compiledPattern.getBuffer(), compiledPattern.length(), values,
+                  appendTo, nullptr, true,
+                  offsets, offsetsLength, errorCode);
+}
+
+UnicodeString &SimpleFormatter::formatAndReplace(
+        const UnicodeString *const *values, int32_t valuesLength,
+        UnicodeString &result,
+        int32_t *offsets, int32_t offsetsLength, UErrorCode &errorCode) const {
+    if (U_FAILURE(errorCode)) {
+        return result;
+    }
+    if (isInvalidArray(values, valuesLength) || isInvalidArray(offsets, offsetsLength)) {
+        errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+        return result;
+    }
+    const char16_t *cp = compiledPattern.getBuffer();
+    int32_t cpLength = compiledPattern.length();
+    if (valuesLength < getArgumentLimit(cp, cpLength)) {
+        errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+        return result;
+    }
+
+    // If the pattern starts with an argument whose value is the same object
+    // as the result, then we keep the result contents and append to it.
+    // Otherwise we replace its contents.
+    int32_t firstArg = -1;
+    // If any non-initial argument value is the same object as the result,
+    // then we first copy its contents and use that instead while formatting.
+    UnicodeString resultCopy;
+    if (getArgumentLimit(cp, cpLength) > 0) {
+        for (int32_t i = 1; i < cpLength;) {
+            int32_t n = cp[i++];
+            if (n < ARG_NUM_LIMIT) {
+                if (values[n] == &result) {
+                    if (i == 2) {
+                        firstArg = n;
+                    } else if (resultCopy.isEmpty() && !result.isEmpty()) {
+                        resultCopy = result;
+                    }
+                }
+            } else {
+                i += n - ARG_NUM_LIMIT;
+            }
+        }
+    }
+    if (firstArg < 0) {
+        result.remove();
+    }
+    return format(cp, cpLength, values,
+                  result, &resultCopy, false,
+                  offsets, offsetsLength, errorCode);
+}
+
+UnicodeString SimpleFormatter::getTextWithNoArguments(
+        const char16_t *compiledPattern,
+        int32_t compiledPatternLength,
+        int32_t* offsets,
+        int32_t offsetsLength) {
+    for (int32_t i = 0; i < offsetsLength; i++) {
+        offsets[i] = -1;
+    }
+    int32_t capacity = compiledPatternLength - 1 -
+            getArgumentLimit(compiledPattern, compiledPatternLength);
+    UnicodeString sb(capacity, 0, 0);  // Java: StringBuilder
+    for (int32_t i = 1; i < compiledPatternLength;) {
+        int32_t n = compiledPattern[i++];
+        if (n > ARG_NUM_LIMIT) {
+            n -= ARG_NUM_LIMIT;
+            sb.append(compiledPattern + i, n);
+            i += n;
+        } else if (n < offsetsLength) {
+            // TODO(ICU-20406): This does not distinguish between "{0}{1}" and "{1}{0}".
+            // Consider removing this function and replacing it with an iterator interface.
+            offsets[n] = sb.length();
+        }
+    }
+    return sb;
+}
+
+UnicodeString &SimpleFormatter::format(
+        const char16_t *compiledPattern, int32_t compiledPatternLength,
+        const UnicodeString *const *values,
+        UnicodeString &result, const UnicodeString *resultCopy, UBool forbidResultAsValue,
+        int32_t *offsets, int32_t offsetsLength,
+        UErrorCode &errorCode) {
+    if (U_FAILURE(errorCode)) {
+        return result;
+    }
+    for (int32_t i = 0; i < offsetsLength; i++) {
+        offsets[i] = -1;
+    }
+    for (int32_t i = 1; i < compiledPatternLength;) {
+        int32_t n = compiledPattern[i++];
+        if (n < ARG_NUM_LIMIT) {
+            const UnicodeString *value = values[n];
+            if (value == nullptr) {
+                errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+                return result;
+            }
+            if (value == &result) {
+                if (forbidResultAsValue) {
+                    errorCode = U_ILLEGAL_ARGUMENT_ERROR;
+                    return result;
+                }
+                if (i == 2) {
+                    // We are appending to result which is also the first value object.
+                    if (n < offsetsLength) {
+                        offsets[n] = 0;
+                    }
+                } else {
+                    if (n < offsetsLength) {
+                        offsets[n] = result.length();
+                    }
+                    result.append(*resultCopy);
+                }
+            } else {
+                if (n < offsetsLength) {
+                    offsets[n] = result.length();
+                }
+                result.append(*value);
+            }
+        } else {
+            int32_t length = n - ARG_NUM_LIMIT;
+            result.append(compiledPattern + i, length);
+            i += length;
+        }
+    }
+    return result;
+}
+
+U_NAMESPACE_END