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#if 0
exec cc -Wall -Wextra -pedantic $@ -o $(dirname $0)/xx $0
#endif
// Hexdump.
#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 allZero(const uint8_t *buf, size_t len) {
for (size_t i = 0; i < len; ++i)
if (buf[i]) return false;
return true;
}
enum {
FLAG_ASCII = 1,
FLAG_OFFSET = 2,
FLAG_SKIP = 4,
FLAG_UNDUMP = 8,
};
void dump(size_t cols, size_t group, uint8_t flags, FILE *file) {
uint8_t buf[cols];
size_t offset = 0, len = 0;
for (;;) {
offset += len;
len = fread(buf, 1, sizeof(buf), file);
if (!len) break;
if ((flags & FLAG_SKIP) && len == sizeof(buf)) {
static bool skip;
if (allZero(buf, len)) {
if (!skip) printf("*\n");
skip = true;
continue;
}
skip = false;
}
if (flags & FLAG_OFFSET) {
printf("%08zx: ", offset);
}
for (size_t i = 0; i < len; ++i) {
if (group && i && !(i % group)) printf(" ");
printf("%02x ", buf[i]);
}
if (flags & FLAG_ASCII) {
for (size_t i = len; i < cols; ++i) {
printf((group && !(i % group)) ? " " : " ");
}
printf(" ");
for (size_t i = 0; i < len; ++i) {
printf("%c", isprint(buf[i]) ? buf[i] : '.');
}
}
printf("\n");
if (len < sizeof(buf)) break;
}
}
void undump(FILE *file) {
uint8_t byte;
int match;
while (1 == (match = fscanf(file, " %hhx", &byte))) {
printf("%c", byte);
}
if (match == 0) errx(EX_DATAERR, "invalid input");
}
int main(int argc, char *argv[]) {
size_t cols = 16;
size_t group = 8;
uint8_t flags = FLAG_ASCII | FLAG_OFFSET;
char *path = NULL;
int opt;
while (0 < (opt = getopt(argc, argv, "ac:fg:hku"))) {
switch (opt) {
case 'a': flags ^= FLAG_ASCII; break;
case 'f': flags ^= FLAG_OFFSET; break;
case 'k': flags ^= FLAG_SKIP; break;
case 'u': flags ^= FLAG_UNDUMP; break;
case 'c': cols = strtoul(optarg, NULL, 10); break;
case 'g': group = strtoul(optarg, NULL, 10); break;
default:
fprintf(stderr, "usage: xx [-afku] [-c cols] [-g group] [file]\n");
return (opt == 'h') ? EX_OK : EX_USAGE;
}
}
if (!cols) return EX_USAGE;
if (argc > optind) {
path = argv[optind];
}
FILE *file = path ? fopen(path, "r") : stdin;
if (!file) err(EX_NOINPUT, "%s", path);
if (flags & FLAG_UNDUMP) {
undump(file);
} else {
dump(cols, group, flags, file);
}
if (ferror(file)) err(EX_IOERR, "%s", path);
return EX_OK;
}
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