/*
 * config.c
 *
 * Summary:  Read config file.
 *
 * Author:  David Hardy
 */

#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include "config.h"
#include "error.h"


int config_init(Config *c)
{
  c->f = NULL;
  return 0;
}


void config_destroy(Config *c)
{
  c->f = NULL;
}


int config_open(Config *c, const char *fname)
{
  c->f = fopen(fname, "r");
  MDIO_ASSERT(c->f != NULL);
  return 0;
}


int config_close(Config *c)
{
  int ret;

  ret = fclose(c->f);
  MDIO_ASSERT(ret == 0);
  return 0;
}


static void parse_line(register char *buf, char **keywd, char **value)
{
  char *cp;

  /* get rid of any leading white space */
  while (isspace((int)*buf)) buf++;

  /* get rid of any trailing comments, delimited by '#' */
  cp = strchr(buf, '#');
  if (cp != NULL) *cp = '\0';

  /* save keyword, get rid of (one) '=' if present */
  *keywd = buf;
  if (*buf == '\0') {
    *value = buf;
    return;
  }
  while (!isspace((int)*buf) && *buf != '=' && *buf != '\0') buf++;
  if (*buf == '\0') {
    *value = buf;
    return;
  }
  else if (*buf == '=') {
    *buf = '\0';
    *value = buf + 1;
    return;
  }
  *buf = '\0';
  buf++;
  while (isspace((int)*buf)) buf++;
  if (*buf == '=') buf++;
  *value = buf;
}


int config_read(Config *c, char *buf, int buflen, char **keywd, char **value)
{
  /* find beginning keyword */
  *value = NULL;
  *keywd = NULL;
  do {
    if (fgets(buf, buflen, c->f) == NULL) return 0;
    parse_line(buf, keywd, value);
  } while (**keywd == '\0' && **value == '\0');  /* skip blank lines */
  return 1;
}