klish/lub/db/db.c

#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
#include <unistd.h>

#include "lub/db.h"

struct passwd *lub_db_getpwnam(const char *name)
{
	size_t size;
	char *buf;
	struct passwd *pwbuf; 
	struct passwd *pw = NULL;
	int res = 0;

	size = sysconf(_SC_GETPW_R_SIZE_MAX);
	pwbuf = malloc(sizeof(*pwbuf) + size);
	if (!pwbuf)
		return NULL;
	buf = (char *)pwbuf + sizeof(*pwbuf);
	
	res = getpwnam_r(name, pwbuf, buf, size, &pw);

	if (res || !pw) {
		free(pwbuf);
		if (res != 0)
			errno = res;
		else
			errno = ENOENT;
		return NULL;
	}
	return pw;
}

struct passwd *lub_db_getpwuid(uid_t uid)
{
	size_t size;
	char *buf;
	struct passwd *pwbuf; 
	struct passwd *pw = NULL;
	int res = 0;

	size = sysconf(_SC_GETPW_R_SIZE_MAX);
	pwbuf = malloc(sizeof(*pwbuf) + size);
	if (!pwbuf)
		return NULL;
	buf = (char *)pwbuf + sizeof(*pwbuf);
	
	res = getpwuid_r(uid, pwbuf, buf, size, &pw);

	if (NULL == pw) {
		free(pwbuf);
		if (res != 0)
			errno = res;
		else
			errno = ENOENT;
		return NULL;
	}

	return pw;
}

struct group *lub_db_getgrnam(const char *name)
{
	size_t size;
	char *buf;
	struct group *grbuf; 
	struct group *gr = NULL;
	int res = 0;

	size = sysconf(_SC_GETGR_R_SIZE_MAX);
	grbuf = malloc(sizeof(*grbuf) + size);
	if (!grbuf)
		return NULL;
	buf = (char *)grbuf + sizeof(*grbuf);
	
	res = getgrnam_r(name, grbuf, buf, size, &gr);

	if (NULL == gr) {
		free(grbuf);
		if (res != 0)
			errno = res;
		else
			errno = ENOENT;
		return NULL;
	}

	return gr;
}

struct group *lub_db_getgrgid(gid_t gid)
{
	size_t size;
	char *buf;
	struct group *grbuf;
	struct group *gr = NULL;
	int res = 0;

	size = sysconf(_SC_GETGR_R_SIZE_MAX);
	grbuf = malloc(sizeof(struct group) + size);
	if (!grbuf)
		return NULL;
	buf = (char *)grbuf + sizeof(struct group);

	res = getgrgid_r(gid, grbuf, buf, size, &gr);

	if (!gr) {
		free(grbuf);
		if (res != 0)
			errno = res;
		else
			errno = ENOENT;
		return NULL;
	}

	return gr;
}