/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8   -*-│
│ vi: set noet ft=c ts=8 sw=8 fenc=utf-8                                   :vi │
╚──────────────────────────────────────────────────────────────────────────────╝
│                                                                              │
│  Musl Libc                                                                   │
│  Copyright © 2005-2014 Rich Felker, et al.                                   │
│                                                                              │
│  Permission is hereby granted, free of charge, to any person obtaining       │
│  a copy of this software and associated documentation files (the             │
│  "Software"), to deal in the Software without restriction, including         │
│  without limitation the rights to use, copy, modify, merge, publish,         │
│  distribute, sublicense, and/or sell copies of the Software, and to          │
│  permit persons to whom the Software is furnished to do so, subject to       │
│  the following conditions:                                                   │
│                                                                              │
│  The above copyright notice and this permission notice shall be              │
│  included in all copies or substantial portions of the Software.             │
│                                                                              │
│  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,             │
│  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF          │
│  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.      │
│  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY        │
│  CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,        │
│  TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE           │
│  SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                      │
│                                                                              │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/struct/dirent.h"
#include "libc/errno.h"
#include "libc/limits.h"
#include "libc/mem/alg.h"
#include "libc/mem/mem.h"
#include "libc/str/str.h"

asm(".ident\t\"\\n\\n\
Musl libc (MIT License)\\n\
Copyright 2005-2014 Rich Felker, et. al.\"");
asm(".include \"libc/disclaimer.inc\"");
// clang-format off

int scandir(const char *path, struct dirent ***res,
	int (*sel)(const struct dirent *),
	int (*cmp)(const struct dirent **, const struct dirent **))
{
	DIR *d = opendir(path);
	struct dirent *de, **names=0, **tmp;
	size_t cnt=0, len=0;
	int old_errno = errno;

	if (!d) return -1;

	while ((errno=0), (de = readdir(d))) {
		if (sel && !sel(de)) continue;
		if (cnt >= len) {
			len = 2*len+1;
			if (len > SIZE_MAX/sizeof *names) break;
			tmp = realloc(names, len * sizeof *names);
			if (!tmp) break;
			names = tmp;
		}
		names[cnt] = malloc(de->d_reclen);
		if (!names[cnt]) break;
		memcpy(names[cnt++], de, de->d_reclen);
	}

	closedir(d);

	if (errno) {
		if (names) while (cnt-->0) free(names[cnt]);
		free(names);
		return -1;
	}
	errno = old_errno;

	if (cmp) qsort(names, cnt, sizeof *names, (int (*)(const void *, const void *))cmp);
	*res = names;
	return cnt;
}