termux-app

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package com.termux.shared.jni.models;
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import androidx.annotation.Keep;
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import androidx.annotation.NonNull;
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import com.termux.shared.logger.Logger;
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/**
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 * A class that can be used to return result for JNI calls with support for multiple fields to easily
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 * return success and error states.
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 *
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 * https://docs.oracle.com/javase/7/docs/technotes/guides/jni/spec/functions.html
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 * https://developer.android.com/training/articles/perf-jni
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 */
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@Keep
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public class JniResult {
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    /**
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     * The return value for the JNI call.
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     * This should be 0 for success.
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     */
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    public int retval;
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    /**
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     * The errno value for any failed native system or library calls if {@link #retval} does not equal 0.
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     * This should be 0 if no errno was set.
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     *
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     * https://manpages.debian.org/testing/manpages-dev/errno.3.en.html
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     */
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    public int errno;
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    /**
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     * The error message for the failure if {@link #retval} does not equal 0.
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     * The message will contain errno message returned by strerror() if errno was set.
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     *
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     * https://manpages.debian.org/testing/manpages-dev/strerror.3.en.html
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     */
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    public String errmsg;
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    /**
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     * Optional additional int data that needs to be returned by JNI call, like bytes read on success.
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     */
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    public int intData;
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    /**
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     * Create an new instance of {@link JniResult}.
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     *
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     * @param retval The {@link #retval} value.
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     * @param errno The {@link #errno} value.
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     * @param errmsg The {@link #errmsg} value.
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     */
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    public JniResult(int retval, int errno, String errmsg) {
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        this.retval = retval;
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        this.errno = errno;
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        this.errmsg = errmsg;
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    }
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    /**
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     * Create an new instance of {@link JniResult}.
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     *
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     * @param retval The {@link #retval} value.
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     * @param errno The {@link #errno} value.
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     * @param errmsg The {@link #errmsg} value.
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     * @param intData The {@link #intData} value.
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     */
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    public JniResult(int retval, int errno, String errmsg, int intData) {
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        this(retval, errno, errmsg);
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        this.intData = intData;
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    }
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    /**
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     * Create an new instance of {@link JniResult} from a {@link Throwable} with {@link #retval} -1.
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     *
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     * @param message The error message.
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     * @param throwable The {@link Throwable} value.
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     */
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    public JniResult(String message, Throwable throwable) {
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        this(-1, 0, Logger.getMessageAndStackTraceString(message, throwable));
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    }
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    /**
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     * Get error {@link String} for {@link JniResult}.
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     *
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     * @param result The {@link JniResult} to get error from.
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     * @return Returns the error {@link String}.
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     */
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    @NonNull
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    public static String getErrorString(final JniResult result) {
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        if (result == null) return "null";
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        return result.getErrorString();
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    }
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    /** Get error {@link String} for {@link JniResult}. */
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    @NonNull
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    public String getErrorString() {
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        StringBuilder logString = new StringBuilder();
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        logString.append(Logger.getSingleLineLogStringEntry("Retval", retval, "-"));
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        if (errno != 0)
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            logString.append("\n").append(Logger.getSingleLineLogStringEntry("Errno", errno, "-"));
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        if (errmsg != null && !errmsg.isEmpty())
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            logString.append("\n").append(Logger.getMultiLineLogStringEntry("Errmsg", errmsg, "-"));
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        return logString.toString();
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    }
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}
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