| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "PathParser.h" |
| |
| #include <errno.h> |
| #include <stdlib.h> |
| #include <utils/Log.h> |
| #include <sstream> |
| #include <string> |
| #include <vector> |
| |
| namespace android { |
| namespace uirenderer { |
| |
| static size_t nextStart(const char* s, size_t length, size_t startIndex) { |
| size_t index = startIndex; |
| while (index < length) { |
| char c = s[index]; |
| // Note that 'e' or 'E' are not valid path commands, but could be |
| // used for floating point numbers' scientific notation. |
| // Therefore, when searching for next command, we should ignore 'e' |
| // and 'E'. |
| if ((((c - 'A') * (c - 'Z') <= 0) || ((c - 'a') * (c - 'z') <= 0)) && c != 'e' && |
| c != 'E') { |
| return index; |
| } |
| index++; |
| } |
| return index; |
| } |
| |
| /** |
| * Calculate the position of the next comma or space or negative sign |
| * @param s the string to search |
| * @param start the position to start searching |
| * @param result the result of the extraction, including the position of the |
| * the starting position of next number, whether it is ending with a '-'. |
| */ |
| static void extract(int* outEndPosition, bool* outEndWithNegOrDot, const char* s, int start, |
| int end) { |
| // Now looking for ' ', ',', '.' or '-' from the start. |
| int currentIndex = start; |
| bool foundSeparator = false; |
| *outEndWithNegOrDot = false; |
| bool secondDot = false; |
| bool isExponential = false; |
| for (; currentIndex < end; currentIndex++) { |
| bool isPrevExponential = isExponential; |
| isExponential = false; |
| char currentChar = s[currentIndex]; |
| switch (currentChar) { |
| case ' ': |
| case ',': |
| foundSeparator = true; |
| break; |
| case '-': |
| // The negative sign following a 'e' or 'E' is not a separator. |
| if (currentIndex != start && !isPrevExponential) { |
| foundSeparator = true; |
| *outEndWithNegOrDot = true; |
| } |
| break; |
| case '.': |
| if (!secondDot) { |
| secondDot = true; |
| } else { |
| // This is the second dot, and it is considered as a separator. |
| foundSeparator = true; |
| *outEndWithNegOrDot = true; |
| } |
| break; |
| case 'e': |
| case 'E': |
| isExponential = true; |
| break; |
| } |
| if (foundSeparator) { |
| break; |
| } |
| } |
| // In the case where nothing is found, we put the end position to the end of |
| // our extract range. Otherwise, end position will be where separator is found. |
| *outEndPosition = currentIndex; |
| } |
| |
| static float parseFloat(PathParser::ParseResult* result, const char* startPtr, |
| size_t expectedLength) { |
| char* endPtr = NULL; |
| float currentValue = strtof(startPtr, &endPtr); |
| if ((currentValue == HUGE_VALF || currentValue == -HUGE_VALF) && errno == ERANGE) { |
| result->failureOccurred = true; |
| result->failureMessage = "Float out of range: "; |
| result->failureMessage.append(startPtr, expectedLength); |
| } |
| if (currentValue == 0 && endPtr == startPtr) { |
| // No conversion is done. |
| result->failureOccurred = true; |
| result->failureMessage = "Float format error when parsing: "; |
| result->failureMessage.append(startPtr, expectedLength); |
| } |
| return currentValue; |
| } |
| |
| /** |
| * Parse the floats in the string. |
| * |
| * @param s the string containing a command and list of floats |
| * @return true on success |
| */ |
| static void getFloats(std::vector<float>* outPoints, PathParser::ParseResult* result, |
| const char* pathStr, int start, int end) { |
| if (pathStr[start] == 'z' || pathStr[start] == 'Z') { |
| return; |
| } |
| int startPosition = start + 1; |
| int endPosition = start; |
| |
| // The startPosition should always be the first character of the |
| // current number, and endPosition is the character after the current |
| // number. |
| while (startPosition < end) { |
| bool endWithNegOrDot; |
| extract(&endPosition, &endWithNegOrDot, pathStr, startPosition, end); |
| |
| if (startPosition < endPosition) { |
| float currentValue = parseFloat(result, &pathStr[startPosition], end - startPosition); |
| if (result->failureOccurred) { |
| return; |
| } |
| outPoints->push_back(currentValue); |
| } |
| |
| if (endWithNegOrDot) { |
| // Keep the '-' or '.' sign with next number. |
| startPosition = endPosition; |
| } else { |
| startPosition = endPosition + 1; |
| } |
| } |
| return; |
| } |
| |
| void PathParser::validateVerbAndPoints(char verb, size_t points, PathParser::ParseResult* result) { |
| size_t numberOfPointsExpected = -1; |
| switch (verb) { |
| case 'z': |
| case 'Z': |
| numberOfPointsExpected = 0; |
| break; |
| case 'm': |
| case 'l': |
| case 't': |
| case 'M': |
| case 'L': |
| case 'T': |
| numberOfPointsExpected = 2; |
| break; |
| case 'h': |
| case 'v': |
| case 'H': |
| case 'V': |
| numberOfPointsExpected = 1; |
| break; |
| case 'c': |
| case 'C': |
| numberOfPointsExpected = 6; |
| break; |
| case 's': |
| case 'q': |
| case 'S': |
| case 'Q': |
| numberOfPointsExpected = 4; |
| break; |
| case 'a': |
| case 'A': |
| numberOfPointsExpected = 7; |
| break; |
| default: |
| result->failureOccurred = true; |
| result->failureMessage += verb; |
| result->failureMessage += " is not a valid verb. "; |
| return; |
| } |
| if (numberOfPointsExpected == 0 && points == 0) { |
| return; |
| } |
| if (numberOfPointsExpected > 0 && points % numberOfPointsExpected == 0) { |
| return; |
| } |
| |
| result->failureOccurred = true; |
| result->failureMessage += verb; |
| result->failureMessage += " needs to be followed by "; |
| if (numberOfPointsExpected > 0) { |
| result->failureMessage += "a multiple of "; |
| } |
| result->failureMessage += std::to_string(numberOfPointsExpected) + " floats. However, " + |
| std::to_string(points) + " float(s) are found. "; |
| } |
| |
| void PathParser::getPathDataFromAsciiString(PathData* data, ParseResult* result, |
| const char* pathStr, size_t strLen) { |
| if (pathStr == NULL) { |
| result->failureOccurred = true; |
| result->failureMessage = "Path string cannot be NULL."; |
| return; |
| } |
| |
| size_t start = 0; |
| // Skip leading spaces. |
| while (isspace(pathStr[start]) && start < strLen) { |
| start++; |
| } |
| if (start == strLen) { |
| result->failureOccurred = true; |
| result->failureMessage = "Path string cannot be empty."; |
| return; |
| } |
| size_t end = start + 1; |
| |
| while (end < strLen) { |
| end = nextStart(pathStr, strLen, end); |
| std::vector<float> points; |
| getFloats(&points, result, pathStr, start, end); |
| validateVerbAndPoints(pathStr[start], points.size(), result); |
| if (result->failureOccurred) { |
| // If either verb or points is not valid, return immediately. |
| result->failureMessage += "Failure occurred at position " + std::to_string(start) + |
| " of path: " + pathStr; |
| return; |
| } |
| data->verbs.push_back(pathStr[start]); |
| data->verbSizes.push_back(points.size()); |
| data->points.insert(data->points.end(), points.begin(), points.end()); |
| start = end; |
| end++; |
| } |
| |
| if ((end - start) == 1 && start < strLen) { |
| validateVerbAndPoints(pathStr[start], 0, result); |
| if (result->failureOccurred) { |
| // If either verb or points is not valid, return immediately. |
| result->failureMessage += "Failure occurred at position " + std::to_string(start) + |
| " of path: " + pathStr; |
| return; |
| } |
| data->verbs.push_back(pathStr[start]); |
| data->verbSizes.push_back(0); |
| } |
| } |
| |
| void PathParser::dump(const PathData& data) { |
| // Print out the path data. |
| size_t start = 0; |
| for (size_t i = 0; i < data.verbs.size(); i++) { |
| std::ostringstream os; |
| os << data.verbs[i]; |
| os << ", verb size: " << data.verbSizes[i]; |
| for (size_t j = 0; j < data.verbSizes[i]; j++) { |
| os << " " << data.points[start + j]; |
| } |
| start += data.verbSizes[i]; |
| ALOGD("%s", os.str().c_str()); |
| } |
| |
| std::ostringstream os; |
| for (size_t i = 0; i < data.points.size(); i++) { |
| os << data.points[i] << ", "; |
| } |
| ALOGD("points are : %s", os.str().c_str()); |
| } |
| |
| void PathParser::parseAsciiStringForSkPath(SkPath* skPath, ParseResult* result, const char* pathStr, |
| size_t strLen) { |
| PathData pathData; |
| getPathDataFromAsciiString(&pathData, result, pathStr, strLen); |
| if (result->failureOccurred) { |
| return; |
| } |
| // Check if there is valid data coming out of parsing the string. |
| if (pathData.verbs.size() == 0) { |
| result->failureOccurred = true; |
| result->failureMessage = "No verbs found in the string for pathData: "; |
| result->failureMessage += pathStr; |
| return; |
| } |
| VectorDrawableUtils::verbsToPath(skPath, pathData); |
| return; |
| } |
| |
| } // namespace uirenderer |
| } // namespace android |