diskutils.c revision a6391f1006b961ca89d1c79a826375380684a4de 
1/* libs/diskconfig/diskutils.c
2 *
3 * Copyright 2008, The Android Open Source Project
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18#define LOG_TAG "diskutils"
19
20#include <errno.h>
21#include <fcntl.h>
22#include <stdio.h>
23#include <stdlib.h>
24#include <string.h>
25#include <unistd.h>
26#include <sys/stat.h>
27
28#include <cutils/log.h>
29
30#include <diskconfig/diskconfig.h>
31
32int
33write_raw_image(const char *dst, const char *src, loff_t offset, int test)
34{
35    int dst_fd = -1;
36    int src_fd = -1;
37    uint8_t buffer[2048];
38    int nr_bytes;
39    int tmp;
40    int done = 0;
41    uint64_t total = 0;
42
43    LOGI("Writing RAW image '%s' to '%s' (offset=%llu)", src, dst, offset);
44    if ((src_fd = open(src, O_RDONLY)) < 0) {
45        LOGE("Could not open %s for reading (errno=%d).", src, errno);
46        goto fail;
47    }
48
49    if (!test) {
50        if ((dst_fd = open(dst, O_RDWR)) < 0) {
51            LOGE("Could not open '%s' for read/write (errno=%d).", dst, errno);
52            goto fail;
53        }
54
55        if (lseek64(dst_fd, offset, SEEK_SET) != offset) {
56            LOGE("Could not seek to offset %lld in %s.", offset, dst);
57            goto fail;
58        }
59    }
60
61    while (!done) {
62        if ((nr_bytes = read(src_fd, buffer, sizeof(buffer))) < 0) {
63            /* XXX: Should we not even bother with EINTR? */
64            if (errno == EINTR)
65                continue;
66            LOGE("Error (%d) while reading from '%s'", errno, src);
67            goto fail;
68        }
69
70        if (!nr_bytes) {
71            /* we're done. */
72            done = 1;
73            break;
74        }
75
76        total += nr_bytes;
77
78        /* skip the write loop if we're testing */
79        if (test)
80            nr_bytes = 0;
81
82        while (nr_bytes > 0) {
83            if ((tmp = write(dst_fd, buffer, nr_bytes)) < 0) {
84                /* XXX: Should we not even bother with EINTR? */
85                if (errno == EINTR)
86                    continue;
87                LOGE("Error (%d) while writing to '%s'", errno, dst);
88                goto fail;
89            }
90            if (!tmp)
91                continue;
92            nr_bytes -= tmp;
93        }
94    }
95
96    if (!done) {
97        LOGE("Exited read/write loop without setting flag! WTF?!");
98        goto fail;
99    }
100
101    if (dst_fd >= 0)
102        fsync(dst_fd);
103
104    LOGI("Wrote %llu bytes to %s @ %lld", total, dst, offset);
105
106    close(src_fd);
107    if (dst_fd >= 0)
108        close(dst_fd);
109    return 0;
110
111fail:
112    if (dst_fd >= 0)
113        close(dst_fd);
114    if (src_fd >= 0)
115        close(src_fd);
116    return 1;
117}
118