view rvinterf/ctracedec/readtab.c @ 407:19e5a3e2f9c0

fcup-settime: moved time() retrieval a little closer to the output A fundamental problem with all simple time transfer tools is that there is always some delay between the time retrieval on the source system and that transmitted time being set on the destination, and the resulting time on the destination system is off by that delay amount. This delay cannot be fully eliminated when working in a simple environment like ours, but we should make our best effort to minimize it. In the present case, moving the atinterf_init() call before the time() retrieval should make a teensy-tiny improvement.
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 11 Aug 2018 21:52:17 +0000
parents e7502631a0f9
children
line wrap: on
line source

/*
 * This module handles the reading and parsing of str2ind.tab
 */

#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <strings.h>
#include <stdlib.h>

extern char *str2ind_tab_filename;

int str2ind_array_size;
char **str2ind_orig_strings;
char **str2ind_param_strings;

static FILE *readF;
static char linebuf[256];
static int lineno;

static void
read_line()
{
	char *cp;

	if (!fgets(linebuf, sizeof linebuf, readF)) {
		fprintf(stderr, "error: premature EOF reading from %s\n",
			str2ind_tab_filename);
		exit(1);
	}
	lineno++;
	cp = index(linebuf, '\n');
	if (!cp) {
		fprintf(stderr,
			"error: %s line %d is too long or unterminated\n",
			str2ind_tab_filename, lineno);
		exit(1);
	}
	*cp = '\0';
	if (cp > linebuf && cp[-1] == '\r')
		cp[-1] = '\0';
}

static void
line_pure_num()
{
	char *cp;

	for (cp = linebuf; isspace(*cp); cp++)
		;
	if (!isdigit(*cp)) {
inv:		fprintf(stderr, "%s line %d: pure number expected\n",
			str2ind_tab_filename, lineno);
		exit(1);
	}
	while (isdigit(*cp))
		cp++;
	if (*cp)
		goto inv;
}

static char *
copystr(str)
	char *str;
{
	static char null = '\0';
	char *buf;

	if (str[0]) {
		buf = malloc(strlen(str) + 1);
		if (!buf) {
			perror("malloc");
			exit(1);
		}
		strcpy(buf, str);
		return(buf);
	} else
		return(&null);
}

static void
process_record_line(idx)
{
	char *cp, *cp2;
	int i;

	for (cp = linebuf; isspace(*cp); cp++)
		;
	if (!isdigit(*cp)) {
syntaxerr:	fprintf(stderr, "%s line %d: unexpected syntax\n",
			str2ind_tab_filename, lineno);
		exit(1);
	}
	while (isdigit(*cp))
		cp++;
	if (*cp++ != ',')
		goto syntaxerr;
	i = atoi(linebuf);
	if (i != idx) {
		fprintf(stderr, "%s line %d lists wrong index (expected %d)\n",
			str2ind_tab_filename, lineno, idx);
		exit(1);
	}
	cp2 = index(cp, ',');
	if (!cp2)
		goto syntaxerr;
	*cp2++ = '\0';
	str2ind_param_strings[idx] = copystr(cp);
	str2ind_orig_strings[idx] = copystr(cp2);
}

read_str2ind_tab()
{
	int idx;

	readF = fopen(str2ind_tab_filename, "r");
	if (!readF) {
		perror(str2ind_tab_filename);
		exit(1);
	}
	/* skip the timestamp line: the user is responsible for matching */
	read_line();
	line_pure_num();
	/* read the line with the array size */
	read_line();
	line_pure_num();
	str2ind_array_size = atoi(linebuf);
	if (str2ind_array_size < 1) {
		fprintf(stderr, "error: %s gives index array size < 1\n",
			str2ind_tab_filename);
		exit(1);
	}
	str2ind_orig_strings = malloc(sizeof(char *) * str2ind_array_size);
	str2ind_param_strings = malloc(sizeof(char *) * str2ind_array_size);
	if (!str2ind_orig_strings || !str2ind_param_strings) {
		perror("malloc");
		exit(1);
	}
	for (idx = 0; idx < str2ind_array_size; idx++) {
		read_line();
		process_record_line(idx);
	}
	fclose(readF);
	return(0);
}