/*
 * Copyright IBM Corporation. 2008
 *
 * Author:	Dhaval Giani <dhaval@linux.vnet.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2.1 of the GNU Lesser General Public License
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Code initiated and designed by Dhaval Giani. All faults are most likely
 * his mistake.
 */

#include <libcgroup.h>
#include <libcgroup-internal.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

struct cgroup *cgroup_new_cgroup(const char *name)
{
	struct cgroup *cgroup = calloc(1, sizeof(struct cgroup));

	if (!cgroup)
		return NULL;

	strncpy(cgroup->name, name, sizeof(cgroup->name));

	return cgroup;
}

struct cgroup_controller *cgroup_add_controller(struct cgroup *cgroup,
							const char *name)
{
	int i;
	struct cgroup_controller *controller;

	if (!cgroup)
		return NULL;

	/*
	 * Still not sure how to handle the failure here.
	 */
	if (cgroup->index >= CG_CONTROLLER_MAX)
		return NULL;

	/*
	 * Still not sure how to handle the failure here.
	 */
	for (i = 0; i < cgroup->index; i++) {
		if (strncmp(name, cgroup->controller[i]->name,
				sizeof(cgroup->controller[i]->name)) == 0)
			return NULL;
	}

	controller = calloc(1, sizeof(struct cgroup_controller));

	if (!controller)
		return NULL;

	strncpy(controller->name, name, sizeof(controller->name));
	controller->index = 0;

	cgroup->controller[cgroup->index] = controller;
	cgroup->index++;

	return controller;
}

void cgroup_free_controllers(struct cgroup *cgroup)
{
	int i, j;

	if (!cgroup)
		return;

	for (i = 0; i < cgroup->index; i++) {
		for (j = 0; j < cgroup->controller[i]->index; j++)
			free(cgroup->controller[i]->values[j]);
		free(cgroup->controller[i]);
	}
}

void cgroup_free(struct cgroup **cgroup)
{
	struct cgroup *cg = *cgroup;

	/*
	 * Passing NULL pointers is OK. We just return.
	 */
	if (!cg)
		return;

	cgroup_free_controllers(cg);
	free(cg);
	*cgroup = NULL;
}

int cgroup_add_value_string(struct cgroup_controller *controller,
					const char *name, const char *value)
{
	int i;
	struct control_value *cntl_value;

	if (!controller)
		return ECGINVAL;

	if (controller->index >= CG_VALUE_MAX)
		return ECGMAXVALUESEXCEEDED;

	for (i = 0; i < controller->index && i < CG_VALUE_MAX; i++) {
		if (!strcmp(controller->values[i]->name, name))
			return ECGVALUEEXISTS;
	}

	cntl_value = calloc(1, sizeof(struct control_value));

	if (!cntl_value)
		return ECGCONTROLLERCREATEFAILED;

	strncpy(cntl_value->name, name, sizeof(cntl_value->name));
	strncpy(cntl_value->value, value, sizeof(cntl_value->value));
	controller->values[controller->index] = cntl_value;
	controller->index++;

	return 0;
}

int cgroup_add_value_int64(struct cgroup_controller *controller,
					const char *name, int64_t value)
{
	int i;
	unsigned ret;
	struct control_value *cntl_value;

	if (!controller)
		return ECGINVAL;

	if (controller->index >= CG_VALUE_MAX)
		return ECGMAXVALUESEXCEEDED;

	for (i = 0; i < controller->index && i < CG_VALUE_MAX; i++) {
		if (!strcmp(controller->values[i]->name, name))
			return ECGVALUEEXISTS;
	}

	cntl_value = calloc(1, sizeof(struct control_value));

	if (!cntl_value)
		return ECGCONTROLLERCREATEFAILED;

	strncpy(cntl_value->name, name,
			sizeof(cntl_value->name));
	ret = snprintf(cntl_value->value,
	  sizeof(cntl_value->value), "%" PRId64, value);

	if (ret >= sizeof(cntl_value->value))
		return ECGINVAL;

	controller->values[controller->index] = cntl_value;
	controller->index++;

	return 0;

}

int cgroup_add_value_uint64(struct cgroup_controller *controller,
					const char *name, u_int64_t value)
{
	int i;
	unsigned ret;
	struct control_value *cntl_value;

	if (!controller)
		return ECGINVAL;

	if (controller->index >= CG_VALUE_MAX)
		return ECGMAXVALUESEXCEEDED;

	for (i = 0; i < controller->index && i < CG_VALUE_MAX; i++) {
		if (!strcmp(controller->values[i]->name, name))
			return ECGVALUEEXISTS;
	}

	cntl_value = calloc(1, sizeof(struct control_value));

	if (!cntl_value)
		return ECGCONTROLLERCREATEFAILED;

	strncpy(cntl_value->name, name,	sizeof(cntl_value->name));
	ret = snprintf(cntl_value->value, sizeof(cntl_value->value),
						"%" PRIu64, value);

	if (ret >= sizeof(cntl_value->value))
		return ECGINVAL;

	controller->values[controller->index] = cntl_value;
	controller->index++;

	return 0;

}

int cgroup_add_value_bool(struct cgroup_controller *controller,
						const char *name, bool value)
{
	int i;
	unsigned ret;
	struct control_value *cntl_value;

	if (!controller)
		return ECGINVAL;

	if (controller->index >= CG_VALUE_MAX)
		return ECGMAXVALUESEXCEEDED;

	for (i = 0; i < controller->index && i < CG_VALUE_MAX; i++) {
		if (!strcmp(controller->values[i]->name, name))
			return ECGVALUEEXISTS;
	}

	cntl_value = calloc(1, sizeof(struct control_value));

	if (!cntl_value)
		return ECGCONTROLLERCREATEFAILED;

	strncpy(cntl_value->name, name, sizeof(cntl_value->name));

	if (value)
		ret = snprintf(cntl_value->value, sizeof(cntl_value->value), "1");
	else
		ret = snprintf(cntl_value->value, sizeof(cntl_value->value), "0");

	if (ret >= sizeof(cntl_value->value))
		return ECGINVAL;

	controller->values[controller->index] = cntl_value;
	controller->index++;

	return 0;
}

int cgroup_compare_controllers(struct cgroup_controller *cgca,
					struct cgroup_controller *cgcb)
{
	int i;

	if (!cgca || !cgcb)
		return ECGINVAL;

	if (strcmp(cgca->name, cgcb->name))
		return ECGCONTROLLERNOTEQUAL;

	if (cgca->index != cgcb->index)
		return ECGCONTROLLERNOTEQUAL;

	for (i = 0; i < cgca->index; i++) {
		struct control_value *cva = cgca->values[i];
		struct control_value *cvb = cgcb->values[i];

		if (strcmp(cva->name, cvb->name))
			return ECGCONTROLLERNOTEQUAL;

		if (strcmp(cva->value, cvb->value))
			return ECGCONTROLLERNOTEQUAL;
	}
	return 0;
}

int cgroup_compare_cgroup(struct cgroup *cgroup_a, struct cgroup *cgroup_b)
{
	int i;

	if (!cgroup_a || !cgroup_b)
		return ECGINVAL;

	if (strcmp(cgroup_a->name, cgroup_b->name))
		return ECGROUPNOTEQUAL;

	if (cgroup_a->tasks_uid != cgroup_b->tasks_uid)
		return ECGROUPNOTEQUAL;

	if (cgroup_a->tasks_gid != cgroup_b->tasks_gid)
		return ECGROUPNOTEQUAL;

	if (cgroup_a->control_uid != cgroup_b->control_uid)
		return ECGROUPNOTEQUAL;

	if (cgroup_a->control_gid != cgroup_b->control_gid)
		return ECGROUPNOTEQUAL;

	if (cgroup_a->index != cgroup_b->index)
		return ECGROUPNOTEQUAL;

	for (i = 0; i < cgroup_a->index; i++) {
		struct cgroup_controller *cgca = cgroup_a->controller[i];
		struct cgroup_controller *cgcb = cgroup_b->controller[i];

		if (cgroup_compare_controllers(cgca, cgcb))
			return ECGCONTROLLERNOTEQUAL;
	}
	return 0;
}

int cgroup_set_uid_gid(struct cgroup *cgroup, uid_t tasks_uid, gid_t tasks_gid,
					uid_t control_uid, gid_t control_gid)
{
	if (!cgroup)
		return ECGINVAL;

	cgroup->tasks_uid = tasks_uid;
	cgroup->tasks_gid = tasks_gid;
	cgroup->control_uid = control_uid;
	cgroup->control_gid = control_gid;

	return 0;
}

int cgroup_get_uid_gid(struct cgroup *cgroup, uid_t *tasks_uid,
		gid_t *tasks_gid, uid_t *control_uid, gid_t *control_gid)
{
	if (!cgroup)
		return ECGINVAL;

	*tasks_uid = cgroup->tasks_uid;
	*tasks_gid = cgroup->tasks_gid;
	*control_uid = cgroup->control_uid;
	*control_gid = cgroup->control_uid;

	return 0;
}

struct cgroup_controller *cgroup_get_controller(struct cgroup *cgroup,
							const char *name)
{
	int i;
	struct cgroup_controller *cgc;

	if (!cgroup)
		return NULL;

	for (i = 0; i < cgroup->index; i++) {
		cgc = cgroup->controller[i];

		if (!strcmp(cgc->name, name))
			return cgc;
	}

	return NULL;
}

int cgroup_get_value_string(struct cgroup_controller *controller,
					const char *name, char **value)
{
	int i;

	if (!controller)
		return ECGINVAL;

	for (i = 0; i < controller->index; i++) {
		struct control_value *val = controller->values[i];

		if (!strcmp(val->name, name)) {
			*value = strdup(val->value);

			if (!*value)
				return ECGOTHER;

			return 0;
		}
	}

	return ECGROUPVALUENOTEXIST;

}

int cgroup_set_value_string(struct cgroup_controller *controller,
					const char *name, const char *value)
{
	int i;

	if (!controller)
		return ECGINVAL;

	for (i = 0; i < controller->index; i++) {
		struct control_value *val = controller->values[i];
		if (!strcmp(val->name, name)) {
			strncpy(val->value, value, CG_VALUE_MAX);
			return 0;
		}
	}

	return cgroup_add_value_string(controller, name, value);
}

int cgroup_get_value_int64(struct cgroup_controller *controller,
					const char *name, int64_t *value)
{
	int i;

	if (!controller)
		return ECGINVAL;

	for (i = 0; i < controller->index; i++) {
		struct control_value *val = controller->values[i];

		if (!strcmp(val->name, name)) {

			if (sscanf(val->value, "%" SCNd64, value) != 1)
				return ECGINVAL;

			return 0;
		}
	}

	return ECGROUPVALUENOTEXIST;
}

int cgroup_set_value_int64(struct cgroup_controller *controller,
					const char *name, int64_t value)
{
	int i;
	unsigned ret;

	if (!controller)
		return ECGINVAL;

	for (i = 0; i < controller->index; i++) {
		struct control_value *val = controller->values[i];

		if (!strcmp(val->name, name)) {
			ret = snprintf(val->value,
				sizeof(val->value), "%" PRId64, value);

			if (ret >= sizeof(val->value) || ret < 0)
				return ECGINVAL;

			return 0;
		}
	}

	return cgroup_add_value_int64(controller, name, value);
}

int cgroup_get_value_uint64(struct cgroup_controller *controller,
					const char *name, u_int64_t *value)
{
	int i;

	if (!controller)
		return ECGINVAL;

	for (i = 0; i < controller->index; i++) {
		struct control_value *val = controller->values[i];
		if (!strcmp(val->name, name)) {

			if (sscanf(val->value, "%" SCNu64, value) != 1)
				return ECGINVAL;

			return 0;
		}
	}

	return ECGROUPVALUENOTEXIST;
}

int cgroup_set_value_uint64(struct cgroup_controller *controller,
					const char *name, u_int64_t value)
{
	int i;
	unsigned ret;

	if (!controller)
		return ECGINVAL;

	for (i = 0; i < controller->index; i++) {
		struct control_value *val = controller->values[i];

		if (!strcmp(val->name, name)) {
			ret = snprintf(val->value,
				sizeof(val->value), "%" PRIu64, value);

			if (ret >= sizeof(val->value) || ret < 0)
				return ECGINVAL;

			return 0;
		}
	}

	return cgroup_add_value_uint64(controller, name, value);
}

int cgroup_get_value_bool(struct cgroup_controller *controller,
						const char *name, bool *value)
{
	int i;

	if (!controller)
		return ECGINVAL;

	for (i = 0; i < controller->index; i++) {
		struct control_value *val = controller->values[i];

		if (!strcmp(val->name, name)) {
			int cgc_val;

			if (sscanf(val->value, "%d", &cgc_val) != 1)
				return ECGINVAL;

			if (cgc_val)
				*value = true;
			else
				*value = false;

			return 0;
		}
	}
	return ECGROUPVALUENOTEXIST;
}

int cgroup_set_value_bool(struct cgroup_controller *controller,
						const char *name, bool value)
{
	int i;
	unsigned ret;

	if (!controller)
		return ECGINVAL;

	for (i = 0; i < controller->index; i++) {
		struct control_value *val = controller->values[i];

		if (!strcmp(val->name, name)) {
			if (value) {
				ret = snprintf(val->value,
						sizeof(val->value), "1");
			} else {
				ret = snprintf(val->value,
						sizeof(val->value), "0");
			}

			if (ret >= sizeof(val->value) || ret < 0)
				return ECGINVAL;

			return 0;

		}
	}

	return cgroup_add_value_bool(controller, name, value);
}