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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "io/lines.h"
#include "util/versie.h"
static void usage(FILE *f) {
fprintf(f,
"Gebruik: omd [-hV] <bestand...>\n"
"\n"
"Draai alle regels om\n"
"\n"
" -h Toon deze hulptekst\n"
" -V Toon versienummer\n");
}
// Returns pointer to argument array containing the file names
static char** parse_options(int argc, char **argv) {
int opt;
while ((opt = getopt(argc, argv, "hV")) != -1) {
switch (opt) {
case 'h':
usage(stdout);
exit(0);
case 'V':
drukkedoos_print_versie(stdout, "omd");
exit(0);
case '?':
usage(stderr);
exit(1);
}
}
return argv + optind;
}
static void reverse_in_place(char *buf, size_t len) {
// TODO: kijk of dit sneller kan met SIMD
for (size_t i = 0, j = len - 1; i < len / 2; i++, j--) {
char c = buf[i];
buf[i] = buf[j];
buf[j] = c;
}
}
static void process(const char *fname, FILE *f) {
struct file_lines fl;
if (!file_lines_open("omd", fname, f, &fl)) exit(1);
while (true) {
struct string_view sv;
if (!file_lines_read(&fl, &sv)) break;
reverse_in_place(sv.s, sv.len);
size_t nw = fwrite(sv.s, 1, sv.len, stdout);
if (nw < sv.len) exit(1);
putchar('\n');
}
file_lines_close(&fl);
}
int entry_omd(int argc, char **argv) {
char **args = parse_options(argc, argv);
if (*args == NULL) {
process(NULL, stdin);
} else {
while (*args != NULL) {
FILE *f = fopen(*args, "r");
if (!f) {
fprintf(stderr, "omd: Kon bestand '%s' niet openen\n", *args);
return 1;
}
process(*args, f);
fclose(f);
args++;
}
}
return 0;
}
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