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#include <getopt.h>
#include <pwd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include "util/debug.h"
#include "util/error.h"
#include "util/loop_args.h"
#include "util/versie.h"
#include "io/read_file.h"
int n, c;
static void usage(FILE *f) {
fprintf(f,
"Gebruik: hoofd [-nchV] [BESTAND]...\n"
"\n"
"Toon de eerste 10 regels van elk BESTAND naar standaard uitvoer\n"
"\n"
" -n AANTAL Aantal regels om weer te geven\n"
" -c AANTAL Aantal karakters om weer te geven\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 *n, int *c) {
int opt;
while ((opt = getopt(argc, argv, "n:c:hV")) != -1) {
switch (opt) {
case 'c':
*c = atoi(optarg);
*n = -1;
break;
case 'n':
*c = -1;
*n = atoi(optarg);
break;
case 'h':
usage(stdout);
exit(0);
case 'V':
drukkedoos_print_versie(stdout);
exit(0);
case '?':
fprintf(stderr, "hoofd: Ongeldige optie: -%c\n", optopt);
usage(stderr);
exit(1);
}
}
return argv + optind;
}
// TODO: be smarter, hoofd doesn't have to read the whole file in memory (for
// unmappable files)
static void process(struct filebuf *fb, int n, int c) {
size_t i;
for (i = 0; i < fb->sz && (n > 0 || n == -1) && (c > 0 || c == -1); i++) {
if (fb->buf[i] == '\n') {
if (n != -1) n--;
}
if (c != -1) c--;
}
fwrite(fb->buf, 1, i, stdout);
free_filebuf(fb);
}
static int handle(char *arg, bool isstdin) {
struct filebuf *fb = NULL;
if (isstdin) {
fb = stream_to_filebuf(stdin, 0);
if (fb == NULL) goto err_stdin;
} else {
bool isdir = false;
fb = file_to_filebuf(arg, 0, &isdir);
if (isdir) goto err_isdir;
else if (fb == NULL) goto err_file;
}
process(fb, n, c);
return 0;
err_stdin:
fprintf(stderr, "hoofd: fout bij lezen van standaard invoer\n");
return 1;
err_file:
fprintf(stderr, "hoofd: fout bij lezen van bestand\n");
return 1;
err_isdir:
fprintf(stderr, "hoofd: bestand '%s' is een mapje\n", arg);
return 1;
}
int entry_hoofd(int argc, char **argv) {
n = 10;
c = -1;
char **args = parse_options(argc, argv, &n, &c);
return loop_args(args, handle);
}
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