/*
 * directory.c -- portable way to open directories
 *
 * Copyright (c) 2011, 2012 David Demelier <markand@malikania.fr>
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "directory.h"

#if defined(_WIN32)	/* WINDOWS */

struct directory *
directory_open(const char *path)
{
	WIN32_FIND_DATA fdata;
	HANDLE h;
	struct directory *res;
	char respath[FILENAME_MAX + 1];

	if (!(res = calloc(1, sizeof (struct directory))))
		return NULL;

	snprintf(respath, sizeof (respath), "%s/*", path);

	if ((h = FindFirstFile(respath, &fdata)) == INVALID_HANDLE_VALUE) {
		free(res);
		return NULL;
	}

	do {
		res->ents = realloc(res->ents,
			        sizeof (*res->ents) * (res->nents + 1));

		/* Fail to reallocate */
		if (!res->ents) {
			free(res);
			res = NULL;
			break;
		}

		res->ents[res->nents].name	= strdup(fdata.cFileName);
		res->ents[res->nents].type	= fdata.dwFileAttributes;
		res->ents[res->nents++].length	= strlen(fdata.cFileName);
	} while (FindNextFile(h, &fdata) != 0);

	return res;
}

const char *
directory_error(void)
{
	static char msg[1024];
	DWORD num;

	num = GetLastError();

	FormatMessage(
	    FORMAT_MESSAGE_FROM_SYSTEM |
	    FORMAT_MESSAGE_IGNORE_INSERTS,
	    NULL,
	    num,
	    MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
	    msg,
	    sizeof (msg),
	    NULL
	);

	return msg;
}

#else			/* UNIX */

#  include <errno.h>

struct directory *
directory_open(const char *path)
{
	DIR *dp;
	struct dirent *ent;
	struct directory *res;

	if (!(res = calloc(1, sizeof (struct directory))))
		return NULL;

	if (!(dp = opendir(path))) {
		free(res);
		return NULL;
	}

	while ((ent = readdir(dp))) {
		res->ents = realloc(res->ents,
			        sizeof (*res->ents) * (res->nents + 1));

		/* Fail to reallocate */
		if (!res->ents) {
			free(res);
			res = NULL;
			break;
		}

		res->ents[res->nents].name	= strdup(ent->d_name);
		res->ents[res->nents].type	= ent->d_type;
		res->ents[res->nents++].length	= ent->d_namlen;
	}

	(void)closedir(dp);

	return res;
}

const char *
directory_error(void)
{
	return strerror(errno);
}

#endif

void
directory_free(struct directory *dir)
{
	int i;

	for (i = 0; i < dir->nents; ++i)
		free(dir->ents[i].name);

	free(dir->ents);
	free(dir);
}