#include "config.h"

#include <sys/types.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include <errno.h>

#include <libgen.h>

#include <limits.h>

#include <grp.h>

#define TEST_GROUP "test/test.group"

static char grfile[PATH_MAX];

static void setup_grfile() __attribute__((constructor));

static void setup_grfile() {

	snprintf(grfile, sizeof(grfile), "%s/%s", BASEDIR, TEST_GROUP);

}

#define ALIGN_MASK(x, mask)    (((x) + (mask)) & ~(mask))

#define ALIGN(x, a)            ALIGN_MASK(x, (typeof(x))(a) - 1)

static int test_getgrent_r(FILE *file, struct group *grp, char *buf,

			   size_t buflen, struct group **result)

{

	char *line, *str, *remain;

	int count, index = 0;

	int gr_mem_cnt = 0;

	*result = NULL;

	line = fgets(buf, buflen, file);

	if (!line)

		return 0;

	/* We'll stuff the gr_mem array in the remaining space in the buffer */

	remain = buf + ALIGN(line + strlen(line) - buf, sizeof(char *));

	grp->gr_mem = (char **)remain;

	count = (buf + buflen - remain) / sizeof (char *);

	if (!count) {

		errno = ERANGE;

		return -1;

	}

	grp->gr_mem[--count] = NULL;

	while ((str = strtok(line, ":"))) {

		char *ptr;

		switch (index++) {

		case 0:

			grp->gr_name = str;

			break;

		case 1:

			grp->gr_passwd = str;

			break;

		case 2:

			errno = 0;

			grp->gr_gid = strtol(str, NULL, 10);

			if (errno)

				return -1;

			break;

		case 3:

			while ((str = strtok_r(str, ",", &ptr))) {

				if (count-- <= 0) {

					errno = ERANGE;

					return -1;

				}

				grp->gr_mem[gr_mem_cnt++] = str;

				str = NULL;

			}

		}

		line = NULL;

	}

	*result = grp;

	return 0;

}

static int test_getgr_match(struct group *grp, char *buf, size_t buflen,

			    struct group **result,

			    int (*match)(const struct group *, const void *),

			    const void *data)

{

	FILE *file;

	struct group *_result;

	*result = NULL;

	file = fopen(grfile, "r");

	if (!file) {

		errno = EBADF;

		return -1;

	}

	errno = 0;

	while (!test_getgrent_r(file, grp, buf, buflen, &_result)) {

		if (!_result)

			break;

		else if (match(grp, data)) {

			*result = grp;

			break;

		}

	}

	fclose(file);

	if (!errno && !*result)

		errno = ENOENT;

	if (errno)

		return -1;

	return 0;

}

static int match_name(const struct group *grp, const void *data)

{

	const char *name = data;

	return !strcmp(grp->gr_name, name);

}

EXPORT

int getgrnam_r(const char *name, struct group *grp, char *buf, size_t buflen,

	       struct group **result)

{

	return test_getgr_match(grp, buf, buflen, result, match_name, name);

}

EXPORT

struct group *getgrnam(const char *name)

{

	static char buf[16384];

	static struct group grp;

	struct group *result;

	(void) getgrnam_r(name, &grp, buf, sizeof(buf), &result);

	return result;

}

static int match_gid(const struct group *grp, const void *data)

{

	gid_t gid = *(gid_t *)data;

	return grp->gr_gid == gid;

}

EXPORT

int getgrgid_r(gid_t gid, struct group *grp, char *buf, size_t buflen,

	       struct group **result)

{

	return test_getgr_match(grp, buf, buflen, result, match_gid, &gid;;

}

EXPORT

struct group *getgrgid(gid_t gid)

{

	static char buf[16384];

	static struct group grp;

	struct group *result;

	(void) getgrgid_r(gid, &grp, buf, sizeof(buf), &result);

	return result;

}