summary refs log tree commit diff
path: root/bin/xx.c
blob: 663ee044eee4ea74aa4ab6f44a23bdb7e37435e4 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/* Copyright (c) 2017, June McEnroe <programble@gmail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <ctype.h>
#include <err.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <sysexits.h>
#include <unistd.h>

static bool zero(const uint8_t *ptr, size_t size) {
	for (size_t i = 0; i < size; ++i) {
		if (ptr[i]) return false;
	}
	return true;
}

static struct {
	size_t cols;
	size_t group;
	bool ascii;
	bool offset;
	bool skip;
} options = { 16, 8, true, true, false };

static void dump(FILE *file) {
	bool skip = false;

	uint8_t buf[options.cols];
	size_t offset = 0;
	for (
		size_t size;
		(size = fread(buf, 1, sizeof(buf), file));
		offset += size
	) {
		if (options.skip) {
			if (zero(buf, size)) {
				if (!skip) printf("*\n");
				skip = true;
				continue;
			} else {
				skip = false;
			}
		}

		if (options.offset) {
			printf("%08zX:  ", offset);
		}

		for (size_t i = 0; i < sizeof(buf); ++i) {
			if (options.group) {
				if (i && !(i % options.group)) {
					printf(" ");
				}
			}
			if (i < size) {
				printf("%02hhX ", buf[i]);
			} else {
				printf("   ");
			}
		}

		if (options.ascii) {
			printf(" ");
			for (size_t i = 0; i < size; ++i) {
				if (options.group) {
					if (i && !(i % options.group)) {
						printf(" ");
					}
				}
				printf("%c", isprint(buf[i]) ? buf[i] : '.');
			}
		}

		printf("\n");
	}
}

static void undump(FILE *file) {
	uint8_t byte;
	int match;
	while (0 < (match = fscanf(file, " %hhx", &byte))) {
		printf("%c", byte);
	}
	if (!match) errx(EX_DATAERR, "invalid input");
}

int main(int argc, char *argv[]) {
	bool reverse = false;
	const char *path = NULL;

	int opt;
	while (0 < (opt = getopt(argc, argv, "ac:g:rsz"))) {
		switch (opt) {
			case 'a': options.ascii ^= true; break;
			case 'c': options.cols = strtoul(optarg, NULL, 0); break;
			case 'g': options.group = strtoul(optarg, NULL, 0); break;
			case 'r': reverse = true; break;
			case 's': options.offset ^= true; break;
			case 'z': options.skip ^= true; break;
			default: return EX_USAGE;
		}
	}
	if (argc > optind) path = argv[optind];
	if (!options.cols) return EX_USAGE;

	FILE *file = path ? fopen(path, "r") : stdin;
	if (!file) err(EX_NOINPUT, "%s", path);

	if (reverse) {
		undump(file);
	} else {
		dump(file);
	}
	if (ferror(file)) err(EX_IOERR, "%s", path);

	return EX_OK;
}