datatop/src/datatop_dual_line_poll.c

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/**
 * @file datatop_dual_line_poll.c
 * @brief Adds ability for data collection from dual line files.
 *
 * File contains methods for searching and polling data from
 * dual line files, meaning the first line contains the dp names
 * while the second line contains the corresponding values.
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "datatop_interface.h"
#include "datatop_fileops.h"
#include "datatop_str.h"

#define DTOP_DUAL_SIZE 8192
#define DTOP_DUAL_LINE (DTOP_DUAL_SIZE>>2)

/**
* @struct dtop_dual_line_vars
* @brief Struct used to hold necessary variables for dual_line_file dpgs.
*
* @var dtop_dual_line_vars::line
* Array of strings where necessary dp names and values are held.
* @var dtop_dual_line_vars::line2
* Array of strings where necessary dp names and values are held.
* @var dtop_dual_line_vars::line_count
* Number of lines the file is that the dpg represents.
*/
struct dtop_dual_line_vars {
	char **line;
	char **line2;
	int line_count;
};

/**
 * @brief Stores the data collected from a dual_line file.
 *
 * @param dpg Struct that polled data is added to.
 * @return DTOP_POLL_IO_ERR - Poll of dpg unsuccessful.
 * @return DTOP_POLL_OK - Poll of dpg successful.
 */
int dtop_dual_line_poll(struct dtop_data_point_gatherer *dpg)
{
	char *data;
	int *line_len = malloc(sizeof(int) *
			((struct dtop_dual_line_vars *)
			(dpg->priv))->line_count);
	int *line_len2 = malloc(sizeof(int) *
			((struct dtop_dual_line_vars *)
			(dpg->priv))->line_count);
	int read;

	struct dt_procdict *dict = malloc(sizeof(struct dt_procdict)
					* (((struct dtop_dual_line_vars *)
					(dpg->priv))->line_count/2));
	struct dt_procdict *prefix_dict = malloc(sizeof(struct dt_procdict)
					* (((struct dtop_dual_line_vars *)
					(dpg->priv))->line_count/2));
	int i, j, k, n, sum, sum2;

	read = dt_read_file(dpg->file, &data, DTOP_DUAL_SIZE);
	if (read == 0 || data == 0)
		return DTOP_POLL_IO_ERR;

	sum = 0;
	sum2 = 0;
	/* Assigns each line read from the file, a length */
	for (n = 0; n < ((struct dtop_dual_line_vars *)
				(dpg->priv))->line_count; n++) {
		line_len[n] = dt_read_line(((struct dtop_dual_line_vars *)
					(dpg->priv))->line[n],
					   DTOP_DUAL_LINE, data,
					   DTOP_DUAL_SIZE, sum);
		line_len2[n] = dt_read_line(((struct dtop_dual_line_vars *)
					(dpg->priv))->line2[n],
					    DTOP_DUAL_LINE, data,
					    DTOP_DUAL_SIZE, sum2);
		if (n <= (((struct dtop_dual_line_vars *)
				(dpg->priv))->line_count-2)) {
			sum += (line_len[n] + 1);
			sum2 += (line_len2[n] + 1);
		}

	}

	/* Stores dp names and values in dictionary */
	for (i = 0; i < (((struct dtop_dual_line_vars *)
				(dpg->priv))->line_count/2); i++)
		dt_parse_proc_dictionary(((struct dtop_dual_line_vars *)
					(dpg->priv))->line[2*i],
					  line_len[2*i],
					  ((struct dtop_dual_line_vars *)
					  (dpg->priv))->line[(2*i)+1],
					  line_len[(2*i)+1],
					  &dict[i]);

	/* Stores dp prefices in dictionary */
	for (i = 0; i < (((struct dtop_dual_line_vars *)
				(dpg->priv))->line_count/2); i++)
		dt_parse_for_prefix(((struct dtop_dual_line_vars *)
				(dpg->priv))->line2[2*i], line_len2[2*i],
				    &prefix_dict[i]);

	/* Assigns a dp value to each dp struct */
	for (k = 0; k < (((struct dtop_dual_line_vars *)
				(dpg->priv))->line_count/2); k++) {
		for (j = 0; j < dpg->data_points_len; j++) {
			i =  dt_find_dict_idx(dpg->data_points[j].name,
					      &dict[k]);
			if (i >= 0 && i < dict[k].max &&
				(strcmp(dpg->data_points[j].prefix,
				prefix_dict[k].val[i]) == 0))

				dtop_store_dp(&(dpg->data_points[j]),
					      dict[k].val[i]);
		}
	}

	dt_free(&data);
	free(line_len);
	free(line_len2);
	free(dict);
	free(prefix_dict);
	return DTOP_POLL_OK;
}

/**
 * @brief Frees dynamically allocated dual_line_file dpgs.
 *
 * Frees the memory of the dpg along with it's data_points
 * and other malloc'd memory no longer needed.
 *
 * @param dpg Dpg to deconstruct and deallocate memory for.
 */
static void dtop_dual_line_dpg_deconstructor
			(struct dtop_data_point_gatherer *dpset)
{
	int i;
	free(dpset->data_points);
	for (i = 0; i < ((struct dtop_dual_line_vars *)
				(dpset->priv))->line_count; i++) {
		free(((struct dtop_dual_line_vars *)(dpset->priv))->line[i]);
		free(((struct dtop_dual_line_vars *)(dpset->priv))->line2[i]);
	}
	free(((struct dtop_dual_line_vars *)(dpset->priv))->line);
	free(((struct dtop_dual_line_vars *)(dpset->priv))->line2);
	free(((struct dtop_dual_line_vars *)(dpset->priv)));
	free(dpset);
}

/**
 * @brief Creates a dpg for a dual_line file.
 *
 * Dynamically allocates memory for dpg which is then added to a linked list
 * via the dtop_register(dpg) function call.
 *
 * @param name Name of file dpg represents.
 * @param data_points dtop_data_point struct that dpg points to.
 * @param storage dtop_dual_line_vars struct that hold relevant dpg variables.
 * @param dp_count Number of datapoints in dtop_data_point struct array.
 */
static void construct_dual_line_file_dpg(char *name, struct dtop_data_point
		*data_points, struct dtop_dual_line_vars *storage, int dp_count)
{
	struct dtop_data_point_gatherer *dpg = malloc
		(sizeof(struct dtop_data_point_gatherer));
	dpg->prefix = name;
	dpg->file = name;
	dpg->poll = dtop_dual_line_poll;
	dpg->data_points = data_points;
	dpg->priv = (struct dtop_dual_line_vars *)storage;
	dpg->data_points_len = dp_count;
	dpg->deconstruct = dtop_dual_line_dpg_deconstructor;

	dtop_register(dpg);
}

/**
 * @brief Scans a dual_line file for all datapoints and creats dps.
 *
 * Searches through a dual_line file (Key on one line with value on next line)
 * for all available data points to create as dp structs.
 *
 * @param name Name of file.
 * @param storage dtop_dual_line_vars struct where relevant variables are stored.
 */
int dtop_dual_line_search(char *name, struct dtop_dual_line_vars *storage)
{
	int i, j, k, n, sum, sum2;
	char *data;
	int *line_len = malloc(sizeof(int) * storage->line_count);
	int *line_len2 = malloc(sizeof(int) * storage->line_count);
	int read;
	struct dt_procdict *dict, *prefix_dict;
	struct dtop_data_point *data_points;
	int dp_count = 0;

	storage->line = malloc(storage->line_count * sizeof(*storage->line));
	storage->line2 = malloc(storage->line_count * sizeof(*storage->line2));
	for (i = 0; i < storage->line_count; i++) {
		storage->line[i] = malloc(sizeof(char) * DTOP_DUAL_LINE);
		storage->line2[i] = malloc(sizeof(char) * DTOP_DUAL_LINE);
	}
	dict = malloc(sizeof(struct dt_procdict) * (storage->line_count/2));
	prefix_dict = malloc(sizeof(struct dt_procdict)
				* (storage->line_count/2));

	read = dt_read_file(name, &data, DTOP_DUAL_SIZE);
	if (read == 0 || data == 0)
		return DTOP_POLL_IO_ERR;

	sum = 0;
	sum2 = 0;
	/* Assigns each line read from the file, a length */
	for (n = 0; n < storage->line_count; n++) {
		line_len[n] = dt_read_line(storage->line[n],
					   DTOP_DUAL_LINE, data,
					   DTOP_DUAL_SIZE, sum);
		line_len2[n] = dt_read_line(storage->line2[n],
					    DTOP_DUAL_LINE, data,
					    DTOP_DUAL_SIZE, sum2);
		if (n <= (storage->line_count-2)) {
			sum += (line_len[n] + 1);
			sum2 += (line_len2[n] + 1);
		}

	}

	/* Stores dp names and prefixes in dictionaries */
	for (i = 0; i < (storage->line_count/2); i++)
		dt_parse_proc_dictionary(storage->line[2*i], line_len[2*i],
			 storage->line[(2*i)+1], line_len[(2*i)+1], &dict[i]);

	for (i = 0; i < (storage->line_count/2); i++)
		dt_parse_for_prefix(storage->line2[2*i], line_len2[2*i],
				    &prefix_dict[i]);

	/* Finds how many data points were gathered from the file */
	for (j = 0; j < (storage->line_count/2); j++) {
		for (i = 0; i < dict[j].max; i++)
			dp_count++;
	}

	data_points = malloc(dp_count * sizeof(struct dtop_data_point));

	k = 0;
	/* Creates a dtop_data_point struct for each dp found in the file */
	for (j = 0; j < (storage->line_count/2); j++)
		for (i = 0; i < dict[j].max; i++) {
			if (dict[j].val[i][0] == '-')
				data_points[k].type = DTOP_LONG;
			else
				data_points[k].type = DTOP_ULONG;
			data_points[k].name = dict[j].key[i];
			data_points[k].prefix = prefix_dict[j].val[i];
			data_points[k].skip = DO_NOT_SKIP;
			data_points[k].initial_data_populated = NOT_POPULATED;
			k++;
		}

	/* Calls dpg constructor, dpg will point to the dp struct */
	construct_dual_line_file_dpg(name, data_points, storage, dp_count);

	free(line_len);
	free(line_len2);
	free(dict);
	free(prefix_dict);
	dt_free(&data);

	return DTOP_POLL_OK;
}

/**
 * @brief Calls dtop_search for a file with dual line pairs.
 */
void dtop_dual_line_init(char *name)
{
	struct dtop_dual_line_vars *storage = malloc
			(sizeof(struct dtop_dual_line_vars));
	storage->line_count = dtop_get_file_line_amount(name);

	if (storage->line_count%2 != 0) {
		printf("Dual line file, %s, contains error.\n", name);
		printf("Data will not be collected from %s\n", name);
		return;
	}
	dtop_dual_line_search(name, storage);
}