94 lines
3.3 KiB
Java
94 lines
3.3 KiB
Java
package nodomain.freeyourgadget.gadgetbridge.util;
|
|
|
|
import org.slf4j.Logger;
|
|
import org.slf4j.LoggerFactory;
|
|
|
|
import java.io.ByteArrayInputStream;
|
|
import java.io.ByteArrayOutputStream;
|
|
import java.io.IOException;
|
|
import java.io.InputStream;
|
|
import java.util.zip.ZipEntry;
|
|
import java.util.zip.ZipException;
|
|
import java.util.zip.ZipInputStream;
|
|
|
|
import androidx.annotation.Nullable;
|
|
|
|
/**
|
|
* Utility class for recognition and reading of ZIP archives.
|
|
*/
|
|
public class ZipFile {
|
|
private static final Logger LOG = LoggerFactory.getLogger(ZipFile.class);
|
|
public static final byte[] ZIP_HEADER = new byte[]{
|
|
0x50, 0x4B, 0x03, 0x04
|
|
};
|
|
|
|
private final byte[] zipBytes;
|
|
|
|
/**
|
|
* Open ZIP file from byte array already in memory.
|
|
* @param zipBytes data to handle as a ZIP file.
|
|
*/
|
|
public ZipFile(byte[] zipBytes) {
|
|
this.zipBytes = zipBytes;
|
|
}
|
|
|
|
/**
|
|
* Open ZIP file from InputStream.<br>
|
|
* This will read the entire file into memory at once.
|
|
* @param inputStream data to handle as a ZIP file.
|
|
*/
|
|
public ZipFile(InputStream inputStream) throws IOException {
|
|
this.zipBytes = readAllBytes(inputStream);
|
|
}
|
|
|
|
/**
|
|
* Checks if data resembles a ZIP file.<br>
|
|
* The check is not infallible: it may report self-extracting or other exotic ZIP archives as not a ZIP file, and it may report a corrupted ZIP file as a ZIP file.
|
|
* @param data The data to check.
|
|
* @return Whether data resembles a ZIP file.
|
|
*/
|
|
public static boolean isZipFile(byte[] data) {
|
|
return ArrayUtils.equals(data, ZIP_HEADER, 0);
|
|
}
|
|
|
|
/**
|
|
* Reads the contents of file at path into a byte array.
|
|
* @param path Path of the file in the ZIP file.
|
|
* @return byte array contatining the contents of the requested file.
|
|
* @throws ZipFileException If the specified path does not exist or references a directory, or if some other I/O error occurs. In other words, if return value would otherwise be null.
|
|
*/
|
|
public byte[] getFileFromZip(final String path) throws ZipFileException {
|
|
try (InputStream is = new ByteArrayInputStream(zipBytes); ZipInputStream zipInputStream = new ZipInputStream(is)) {
|
|
ZipEntry zipEntry;
|
|
while ((zipEntry = zipInputStream.getNextEntry()) != null) {
|
|
if (!zipEntry.getName().equals(path)) continue; // TODO: is this always a path? The documentation is very vague.
|
|
|
|
if (zipEntry.isDirectory()) {
|
|
throw new ZipFileException(String.format("Path in ZIP file is a directory: %s", path));
|
|
}
|
|
|
|
return readAllBytes(zipInputStream);
|
|
}
|
|
|
|
throw new ZipFileException(String.format("Path in ZIP file was not found: %s", path));
|
|
|
|
} catch (ZipException e) {
|
|
throw new ZipFileException("The ZIP file might be corrupted");
|
|
} catch (IOException e) {
|
|
throw new ZipFileException("General IO error");
|
|
}
|
|
}
|
|
|
|
private static byte[] readAllBytes(final InputStream is) throws IOException {
|
|
final ByteArrayOutputStream buffer = new ByteArrayOutputStream();
|
|
|
|
int n;
|
|
byte[] buf = new byte[16384];
|
|
|
|
while ((n = is.read(buf, 0, buf.length)) != -1) {
|
|
buffer.write(buf, 0, n);
|
|
}
|
|
|
|
return buffer.toByteArray();
|
|
}
|
|
} |