openrc/src/librc/librc-misc.c

/*
  rc-misc.c
  rc misc functions
*/

/*
 * Copyright (c) 2007-2008 Roy Marples <roy@marples.name>
 * All rights reserved

 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "librc.h"

bool
rc_yesno(const char *value)
{
	if (!value) {
		errno = ENOENT;
		return false;
	}

	if (strcasecmp(value, "yes") == 0 ||
	    strcasecmp(value, "y") == 0 ||
	    strcasecmp(value, "true") == 0 ||
	    strcasecmp(value, "1") == 0)
		return true;

	if (strcasecmp(value, "no") != 0 &&
	    strcasecmp(value, "n") != 0 &&
	    strcasecmp(value, "false") != 0 &&
	    strcasecmp(value, "0") != 0)
		errno = EINVAL;

	return false;
}
librc_hidden_def(rc_yesno)

ssize_t
rc_getline(char **line, size_t *len, FILE *fp)
{
	char *p;
	size_t last = 0;

	while(!feof(fp)) {
		if (*line == NULL || last != 0) {
			*len += BUFSIZ;
			*line = xrealloc(*line, *len);
		}
		p = *line + last;
		memset(p, 0, BUFSIZ);
		if (fgets(p, BUFSIZ, fp) == NULL)
			break;
		last += strlen(p);
		if (last && (*line)[last - 1] == '\n') {
			(*line)[last - 1] = '\0';
			break;
		}
	}
	return last;
}
librc_hidden_def(rc_getline)

RC_STRINGLIST *
rc_config_list(const char *file)
{
	FILE *fp;
	char *buffer = NULL;
	size_t len = 0;
	char *p;
	char *token;
	RC_STRINGLIST *list = rc_stringlist_new();

	if (!(fp = fopen(file, "r")))
		return list;

	while ((rc_getline(&buffer, &len, fp))) {
		p = buffer;
		/* Strip leading spaces/tabs */
		while ((*p == ' ') || (*p == '\t'))
			p++;

		/* Get entry - we do not want comments */
		token = strsep(&p, "#");
		if (token && (strlen(token) > 1)) {
			/* If not variable assignment then skip */
			if (strchr(token, '=')) {
				/* Stip the newline if present */
				if (token[strlen(token) - 1] == '\n')
					token[strlen(token) - 1] = 0;

				rc_stringlist_add(list, token);
			}
		}
	}
	fclose(fp);
	free(buffer);

	return list;
}
librc_hidden_def(rc_config_list)

RC_STRINGLIST *
rc_config_load(const char *file)
{
	RC_STRINGLIST *list;
	RC_STRINGLIST *config;
	char *token;
	RC_STRING *line;
	RC_STRING *cline;
	size_t i = 0;
	bool replaced;
	char *entry;
	char *newline;
	char *p;

	list = rc_config_list(file);
	config = rc_stringlist_new();
	TAILQ_FOREACH(line, list, entries) {
		/* Get entry */
		p = line->value;
		if (! p)
			continue;
		if (strncmp(p, "export ", 7) == 0)
			p += 7;
		if (! (token = strsep(&p, "=")))
			continue;

		entry = xstrdup(token);
		/* Preserve shell coloring */
		if (*p == '$')
			token = line->value;
		else
			do {
				/* Bash variables are usually quoted */
				token = strsep(&p, "\"\'");
			} while (token && *token == '\0');

		/* Drop a newline if that's all we have */
		if (token) {
			i = strlen(token) - 1;
			if (token[i] == '\n')
				token[i] = 0;

			i = strlen(entry) + strlen(token) + 2;
			newline = xmalloc(sizeof(char) * i);
			snprintf(newline, i, "%s=%s", entry, token);
		} else {
			i = strlen(entry) + 2;
			newline = xmalloc(sizeof(char) * i);
			snprintf(newline, i, "%s=", entry);
		}

		replaced = false;
		/* In shells the last item takes precedence, so we need to remove
		   any prior values we may already have */
		TAILQ_FOREACH(cline, config, entries) {
			p = strchr(cline->value, '=');
			if (p && strncmp(entry, cline->value,
				(size_t)(p - cline->value)) == 0)
			{
				/* We have a match now - to save time we directly replace it */
				free(cline->value);
				cline->value = newline;
				replaced = true;
				break;
			}
		}

		if (!replaced) {
			rc_stringlist_add(config, newline);
			free(newline);
		}
		free(entry);
	}
	rc_stringlist_free(list);

	return config;
}
librc_hidden_def(rc_config_load)

char *
rc_config_value(RC_STRINGLIST *list, const char *entry)
{
	RC_STRING *line;
	char *p;
	size_t len, dif;

	len = strlen(entry);
	TAILQ_FOREACH(line, list, entries) {
		p = strchr(line->value, '=');
		if (p != NULL) {
			dif = (p - line->value);
			if (dif == len &&
			    strncmp(entry, line->value, dif) == 0)
				return ++p;
		}
	}
	return NULL;
}
librc_hidden_def(rc_config_value)