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#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "util/map.h"
#include "util/versie.h"
static void usage(FILE *f) {
fprintf(f,
"Gebruik: tak [-hV] <bestand...>\n"
"\n"
"Schakel bestanden aaneen naar standaard uitvoer omgekeerd.\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, "tak");
exit(0);
case '?':
usage(stderr);
exit(1);
}
}
return argv + optind;
}
struct state {
char *buf;
size_t sz;
};
static void process(struct state state) {
char *lstart, *lend;
lend = &state.buf[state.sz - 1];
while (lend > state.buf) {
if (*lend == '\n') {
lend--;
}
lstart = lend;
while (*lstart != '\n' && lstart != state.buf) {
lstart--;
}
if (lstart != state.buf) {
lstart++;
}
fwrite(lstart, 1, lend - lstart + 2, stdout);
lend = lstart-1;
}
}
#define CHECK_OOM(ptr) \
if (ptr == NULL) { \
fprintf(stderr, "tak: geheugen is op"); \
/* I think I should free the original memory here, but whatever */ \
return NULL; \
}
static char *read_stdin(size_t *sz) {
*sz = 0;
size_t cap = 4096;
char *res = malloc(cap);
CHECK_OOM(res);
while (!feof(stdin)) {
if (cap-*sz == 0) {
cap *= 2;
res = realloc(res, cap);
CHECK_OOM(res);
}
const size_t amount = cap-*sz;
const size_t n = fread(res+*sz, 1, amount, stdin);
*sz += n;
if (n != amount && !feof(stdin)) {
fprintf(stderr, "tak: fout tijdens lezen van standaard invoer.\n");
free(res);
return NULL;
}
}
return res;
}
int entry_tak(int argc, char **argv) {
char **args = parse_options(argc, argv);
if (*args == NULL) {
size_t sz = 0;
char *data = read_stdin(&sz);
if (data == NULL) {
return 1;
}
struct state state = { .buf = data, .sz = sz };
process(state);
free(data);
} else {
while (*args != NULL) {
struct map *map = open_map(*args);
if (map == NULL) {
return 1;
}
struct state state = { .buf = map->addr, .sz = map->sb.st_size };
process(state);
close_map(map);
args++;
}
}
return 0;
}
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