1 /*
2 * Copyright (C) 2022 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <usbhost/usbhost_jni.h>
18
19 #include "usbhost_private.h"
20
21 #include <errno.h>
22 #include <string.h>
23 #include <unistd.h>
24
usb_jni_read_descriptors(JNIEnv * env,int fd)25 jbyteArray usb_jni_read_descriptors(JNIEnv* env, int fd) {
26 if (TEMP_FAILURE_RETRY(lseek(fd, 0, SEEK_SET)) == -1) {
27 ALOGE("usb_jni_read_descriptors(%d): lseek() failed: %s", fd, strerror(errno));
28 return NULL;
29 }
30
31 jbyte buf[MAX_DESCRIPTORS_LENGTH];
32 ssize_t n = TEMP_FAILURE_RETRY(read(fd, buf, sizeof(buf)));
33 if (n == -1) {
34 ALOGE("usb_jni_read_descriptors: read failed: %s", strerror(errno));
35 return NULL;
36 }
37
38 jbyteArray result = env->NewByteArray(n);
39 if (result) env->SetByteArrayRegion(result, 0, n, buf);
40 return result;
41 }
42