b05b0b5d3b
This adds a new function to libcutils, partition_wiped(). This is used to determine if a partition is wiped. Change-Id: Ibb388976c6b5bd3923b62d8f79b2b97748abf6c1
67 lines
1.5 KiB
C
67 lines
1.5 KiB
C
/*
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* Copyright 2011, The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include <sys/types.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include <sys/stat.h>
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#include <sys/ioctl.h>
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#include <sys/mount.h> /* for BLKGETSIZE */
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#include <cutils/properties.h>
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static int only_one_char(char *buf, int len, char c)
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{
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int i, ret;
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ret = 1;
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for (i=0; i<len; i++) {
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if (buf[i] != c) {
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ret = 0;
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break;
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}
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}
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return ret;
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}
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int partition_wiped(char *source)
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{
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char buf[4096];
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int fd, ret, wiped;
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if ((fd = open(source, O_RDONLY)) < 0) {
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return 0;
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}
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ret = read(fd, buf, sizeof(buf));
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close(fd);
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if (ret != sizeof(buf)) {
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return 0;
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}
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/* Check for all zeros */
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if (only_one_char(buf, sizeof(buf), 0)) {
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return 1;
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}
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/* Check for all ones */
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if (only_one_char(buf, sizeof(buf), 0xff)) {
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return 1;
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}
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return 0;
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}
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