| /* |
| * Copyright (C) 2016 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. |
| */ |
| |
| package com.android.apksigner; |
| |
| import java.util.Arrays; |
| |
| /** |
| * Parser of command-line options/switches/flags. |
| * |
| * <p>Supported option formats: |
| * <ul> |
| * <li>{@code --name value}</li> |
| * <li>{@code --name=value}</li> |
| * <li>{@code -name value}</li> |
| * <li>{@code --name} (boolean options only)</li> |
| * </ul> |
| * |
| * <p>To use the parser, create an instance, providing it with the command-line parameters, then |
| * iterate over options by invoking {@link #nextOption()} until it returns {@code null}. |
| */ |
| class OptionsParser { |
| private final String[] mParams; |
| private int mIndex; |
| private int mPutBackIndex; |
| private String mLastOptionValue; |
| private String mPutBackLastOptionValue; |
| private String mLastOptionOriginalForm; |
| private String mPutBackLastOptionOriginalForm; |
| |
| /** |
| * Constructs a new {@code OptionsParser} initialized with the provided command-line. |
| */ |
| public OptionsParser(String[] params) { |
| mParams = params.clone(); |
| } |
| |
| /** |
| * Returns the name (without leading dashes) of the next option (starting with the very first |
| * option) or {@code null} if there are no options left. |
| * |
| * <p>The value of this option can be obtained via {@link #getRequiredValue(String)}, |
| * {@link #getRequiredIntValue(String)}, and {@link #getOptionalBooleanValue(boolean)}. |
| */ |
| public String nextOption() { |
| if (mIndex >= mParams.length) { |
| // No more parameters left |
| return null; |
| } |
| String param = mParams[mIndex]; |
| if (!param.startsWith("-")) { |
| // Not an option |
| return null; |
| } |
| |
| mPutBackIndex = mIndex; |
| mIndex++; |
| mPutBackLastOptionOriginalForm = mLastOptionOriginalForm; |
| mLastOptionOriginalForm = param; |
| mPutBackLastOptionValue = mLastOptionValue; |
| mLastOptionValue = null; |
| if (param.startsWith("--")) { |
| // FORMAT: --name value OR --name=value |
| if ("--".equals(param)) { |
| // End of options marker |
| return null; |
| } |
| int valueDelimiterIndex = param.indexOf('='); |
| if (valueDelimiterIndex != -1) { |
| mLastOptionValue = param.substring(valueDelimiterIndex + 1); |
| mLastOptionOriginalForm = param.substring(0, valueDelimiterIndex); |
| return param.substring("--".length(), valueDelimiterIndex); |
| } else { |
| return param.substring("--".length()); |
| } |
| } else { |
| // FORMAT: -name value |
| return param.substring("-".length()); |
| } |
| } |
| |
| /** |
| * Undoes the last call to nextOption(), if one was made. This allows callers to unwind state |
| * so as not to eat up an option that is meant to be processed elsewhere. |
| */ |
| public void putOption() { |
| mIndex = mPutBackIndex; |
| mLastOptionOriginalForm = mPutBackLastOptionOriginalForm; |
| mLastOptionValue = mPutBackLastOptionValue; |
| } |
| /** |
| * Returns the original form of the current option. The original form includes the leading dash |
| * or dashes. This is intended to be used for referencing the option in error messages. |
| */ |
| public String getOptionOriginalForm() { |
| return mLastOptionOriginalForm; |
| } |
| |
| /** |
| * Returns the value of the current option, throwing an exception if the value is missing. |
| */ |
| public String getRequiredValue(String valueDescription) throws OptionsException { |
| if (mLastOptionValue != null) { |
| String result = mLastOptionValue; |
| mLastOptionValue = null; |
| return result; |
| } |
| if (mIndex >= mParams.length) { |
| // No more parameters left |
| throw new OptionsException( |
| valueDescription + " missing after " + mLastOptionOriginalForm); |
| } |
| String param = mParams[mIndex]; |
| if ("--".equals(param)) { |
| // End of options marker |
| throw new OptionsException( |
| valueDescription + " missing after " + mLastOptionOriginalForm); |
| } |
| mIndex++; |
| return param; |
| } |
| |
| /** |
| * Returns the value of the current numeric option, throwing an exception if the value is |
| * missing or is not numeric. |
| */ |
| public int getRequiredIntValue(String valueDescription) throws OptionsException { |
| String value = getRequiredValue(valueDescription); |
| try { |
| return Integer.parseInt(value); |
| } catch (NumberFormatException e) { |
| throw new OptionsException( |
| valueDescription + " (" + mLastOptionOriginalForm |
| + ") must be a decimal number: " + value); |
| } |
| } |
| |
| /** |
| * Gets the value of the current boolean option. Boolean options are not required to have |
| * explicitly specified values. |
| */ |
| public boolean getOptionalBooleanValue(boolean defaultValue) throws OptionsException { |
| if (mLastOptionValue != null) { |
| // --option=value form |
| String stringValue = mLastOptionValue; |
| mLastOptionValue = null; |
| if ("true".equals(stringValue)) { |
| return true; |
| } else if ("false".equals(stringValue)) { |
| return false; |
| } |
| throw new OptionsException( |
| "Unsupported value for " + mLastOptionOriginalForm + ": " + stringValue |
| + ". Only true or false supported."); |
| } |
| |
| // --option (true|false) form OR just --option |
| if (mIndex >= mParams.length) { |
| return defaultValue; |
| } |
| |
| String stringValue = mParams[mIndex]; |
| if ("true".equals(stringValue)) { |
| mIndex++; |
| return true; |
| } else if ("false".equals(stringValue)) { |
| mIndex++; |
| return false; |
| } else { |
| return defaultValue; |
| } |
| } |
| |
| /** |
| * Returns the remaining command-line parameters. This is intended to be invoked once |
| * {@link #nextOption()} returns {@code null}. |
| */ |
| public String[] getRemainingParams() { |
| if (mIndex >= mParams.length) { |
| return new String[0]; |
| } |
| String param = mParams[mIndex]; |
| if ("--".equals(param)) { |
| // Skip end of options marker |
| return Arrays.copyOfRange(mParams, mIndex + 1, mParams.length); |
| } else { |
| return Arrays.copyOfRange(mParams, mIndex, mParams.length); |
| } |
| } |
| |
| /** |
| * Indicates that an error was encountered while parsing command-line options. |
| */ |
| public static class OptionsException extends Exception { |
| private static final long serialVersionUID = 1L; |
| |
| public OptionsException(String message) { |
| super(message); |
| } |
| } |
| } |