1 /* $NetBSD: fdtoverlay.c,v 1.1.1.1 2019/12/22 12:34:03 skrll Exp $ */
2
3 // SPDX-License-Identifier: GPL-2.0-or-later
4 /*
5 * Copyright (c) 2017 Konsulko Group Inc. All rights reserved.
6 *
7 * Author:
8 * Pantelis Antoniou <pantelis.antoniou@konsulko.com>
9 */
10
11 #include <assert.h>
12 #include <ctype.h>
13 #include <getopt.h>
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <string.h>
17 #include <inttypes.h>
18
19 #include <libfdt.h>
20
21 #include "util.h"
22
23 #define BUF_INCREMENT 65536
24
25 /* Usage related data. */
26 static const char usage_synopsis[] =
27 "apply a number of overlays to a base blob\n"
28 " fdtoverlay <options> [<overlay.dtbo> [<overlay.dtbo>]]\n"
29 "\n"
30 USAGE_TYPE_MSG;
31 static const char usage_short_opts[] = "i:o:v" USAGE_COMMON_SHORT_OPTS;
32 static struct option const usage_long_opts[] = {
33 {"input", required_argument, NULL, 'i'},
34 {"output", required_argument, NULL, 'o'},
35 {"verbose", no_argument, NULL, 'v'},
36 USAGE_COMMON_LONG_OPTS,
37 };
38 static const char * const usage_opts_help[] = {
39 "Input base DT blob",
40 "Output DT blob",
41 "Verbose messages",
42 USAGE_COMMON_OPTS_HELP
43 };
44
45 int verbose = 0;
46
apply_one(char * base,const char * overlay,size_t * buf_len,const char * name)47 static void *apply_one(char *base, const char *overlay, size_t *buf_len,
48 const char *name)
49 {
50 char *tmp = NULL;
51 char *tmpo;
52 int ret;
53
54 /*
55 * We take a copies first, because a a failed apply can trash
56 * both the base blob and the overlay
57 */
58 tmpo = xmalloc(fdt_totalsize(overlay));
59
60 do {
61 tmp = xrealloc(tmp, *buf_len);
62 ret = fdt_open_into(base, tmp, *buf_len);
63 if (ret) {
64 fprintf(stderr,
65 "\nFailed to make temporary copy: %s\n",
66 fdt_strerror(ret));
67 goto fail;
68 }
69
70 memcpy(tmpo, overlay, fdt_totalsize(overlay));
71
72 ret = fdt_overlay_apply(tmp, tmpo);
73 if (ret == -FDT_ERR_NOSPACE) {
74 *buf_len += BUF_INCREMENT;
75 }
76 } while (ret == -FDT_ERR_NOSPACE);
77
78 if (ret) {
79 fprintf(stderr, "\nFailed to apply '%s': %s\n",
80 name, fdt_strerror(ret));
81 goto fail;
82 }
83
84 free(base);
85 free(tmpo);
86 return tmp;
87
88 fail:
89 free(tmpo);
90 if (tmp)
91 free(tmp);
92
93 return NULL;
94 }
do_fdtoverlay(const char * input_filename,const char * output_filename,int argc,char * argv[])95 static int do_fdtoverlay(const char *input_filename,
96 const char *output_filename,
97 int argc, char *argv[])
98 {
99 char *blob = NULL;
100 char **ovblob = NULL;
101 size_t buf_len;
102 int i, ret = -1;
103
104 blob = utilfdt_read(input_filename, &buf_len);
105 if (!blob) {
106 fprintf(stderr, "\nFailed to read '%s'\n", input_filename);
107 goto out_err;
108 }
109 if (fdt_totalsize(blob) > buf_len) {
110 fprintf(stderr,
111 "\nBase blob is incomplete (%lu / %" PRIu32 " bytes read)\n",
112 (unsigned long)buf_len, fdt_totalsize(blob));
113 goto out_err;
114 }
115 ret = 0;
116
117 /* allocate blob pointer array */
118 ovblob = xmalloc(sizeof(*ovblob) * argc);
119 memset(ovblob, 0, sizeof(*ovblob) * argc);
120
121 /* read and keep track of the overlay blobs */
122 for (i = 0; i < argc; i++) {
123 size_t ov_len;
124 ovblob[i] = utilfdt_read(argv[i], &ov_len);
125 if (!ovblob[i]) {
126 fprintf(stderr, "\nFailed to read '%s'\n", argv[i]);
127 goto out_err;
128 }
129 if (fdt_totalsize(ovblob[i]) > ov_len) {
130 fprintf(stderr,
131 "\nOverlay '%s' is incomplete (%lu / %" PRIu32 " bytes read)\n",
132 argv[i], (unsigned long)ov_len,
133 fdt_totalsize(ovblob[i]));
134 goto out_err;
135 }
136 }
137
138 buf_len = fdt_totalsize(blob);
139
140 /* apply the overlays in sequence */
141 for (i = 0; i < argc; i++) {
142 blob = apply_one(blob, ovblob[i], &buf_len, argv[i]);
143 if (!blob)
144 goto out_err;
145 }
146
147 fdt_pack(blob);
148 ret = utilfdt_write(output_filename, blob);
149 if (ret)
150 fprintf(stderr, "\nFailed to write '%s'\n",
151 output_filename);
152
153 out_err:
154 if (ovblob) {
155 for (i = 0; i < argc; i++) {
156 if (ovblob[i])
157 free(ovblob[i]);
158 }
159 free(ovblob);
160 }
161 free(blob);
162
163 return ret;
164 }
165
main(int argc,char * argv[])166 int main(int argc, char *argv[])
167 {
168 int opt, i;
169 char *input_filename = NULL;
170 char *output_filename = NULL;
171
172 while ((opt = util_getopt_long()) != EOF) {
173 switch (opt) {
174 case_USAGE_COMMON_FLAGS
175
176 case 'i':
177 input_filename = optarg;
178 break;
179 case 'o':
180 output_filename = optarg;
181 break;
182 case 'v':
183 verbose = 1;
184 break;
185 }
186 }
187
188 if (!input_filename)
189 usage("missing input file");
190
191 if (!output_filename)
192 usage("missing output file");
193
194 argv += optind;
195 argc -= optind;
196
197 if (argc <= 0)
198 usage("missing overlay file(s)");
199
200 if (verbose) {
201 printf("input = %s\n", input_filename);
202 printf("output = %s\n", output_filename);
203 for (i = 0; i < argc; i++)
204 printf("overlay[%d] = %s\n", i, argv[i]);
205 }
206
207 if (do_fdtoverlay(input_filename, output_filename, argc, argv))
208 return 1;
209
210 return 0;
211 }
212