/****************************************************************************
* tools/cfgpaser.c
*
* Copyright (C) 2007-2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include "cfgparser.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Public Data
****************************************************************************/
char line[LINESIZE+1];
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/* Skip over any spaces */
static char *skip_space(char *ptr)
{
while (*ptr && isspace((int)*ptr)) ptr++;
return ptr;
}
/* Find the end of a variable string */
static char *find_name_end(char *ptr)
{
while (*ptr && (isalnum((int)*ptr) || *ptr == '_')) ptr++;
return ptr;
}
/* Find the end of a value string */
static char *find_value_end(char *ptr)
{
while (*ptr && !isspace((int)*ptr))
{
if (*ptr == '"')
{
do ptr++; while (*ptr && *ptr != '"');
if (*ptr) ptr++;
}
else
{
do ptr++; while (*ptr && !isspace((int)*ptr) && *ptr != '"');
}
}
return ptr;
}
/* Read the next line from the configuration file */
static char *read_line(FILE *stream)
{
char *ptr;
for (;;)
{
line[LINESIZE] = '\0';
if (!fgets(line, LINESIZE, stream))
{
return NULL;
}
else
{
ptr = skip_space(line);
if (*ptr && *ptr != '#' && *ptr != '\n')
{
return ptr;
}
}
}
}
/* Parse the line from the configuration file into a variable name
* string and a value string.
*/
static void parse_line(char *ptr, char **varname, char **varval)
{
/* Skip over any leading spaces */
ptr = skip_space(ptr);
/* The first no-space is the beginning of the variable name */
*varname = skip_space(ptr);
*varval = NULL;
/* Parse to the end of the variable name */
ptr = find_name_end(ptr);
/* An equal sign is expected next, perhaps after some white space */
if (*ptr && *ptr != '=')
{
/* Some else follows the variable name. Terminate the variable
* name and skip over any spaces.
*/
*ptr = '\0';
ptr = skip_space(ptr + 1);
}
/* Verify that the equal sign is present */
if (*ptr == '=')
{
/* Make sure that the variable name is terminated (this was already
* done if the name was followed by white space.
*/
*ptr = '\0';
/* The variable value should follow =, perhaps separated by some
* white space.
*/
ptr = skip_space(ptr + 1);
if (*ptr)
{
/* Yes.. a variable follows. Save the pointer to the start
* of the variable string.
*/
*varval = ptr;
/* Find the end of the variable string and make sure that it
* is terminated.
*/
ptr = find_value_end(ptr);
*ptr = '\0';
}
}
}
/****************************************************************************
* Public Functions
****************************************************************************/
void parse_file(FILE *stream, struct variable_s **list)
{
struct variable_s *curr;
struct variable_s *prev;
struct variable_s *next;
char *varname;
char *varval;
char *ptr;
/* Loop until the entire file has been parsed. */
do
{
/* Read the next line from the file */
ptr = read_line(stream);
if (ptr)
{
/* Parse the line into a variable and a value field */
parse_line(ptr, &varname, &varval);
/* If the variable has not value (or the special value 'n'), then
* ignore it.
*/
if (!varval || strcmp(varval, "n") == 0)
{
continue;
}
/* Make sure that a variable name was found. */
if (varname)
{
int varlen = strlen(varname) + 1;
int vallen = 0;
/* Get the size of the value, including the NUL terminating
* character.
*/
if (varval)
{
vallen = strlen(varval) + 1;
}
/* Allocate memory to hold the struct variable_s with the
* variable name and the value.
*/
curr = (struct variable_s *)malloc(sizeof(struct variable_s) + varlen + vallen - 1);
if (curr)
{
/* Add the variable to the list */
curr->var = &curr->storage[0];
strcpy(curr->var, varname);
curr->val = NULL;
if (varval)
{
curr->val = &curr->storage[varlen];
strcpy(curr->val, varval);
}
prev = 0;
next = *list;
while (next && strcmp(next->var, curr->var) <= 0)
{
prev = next;
next = next->flink;
}
if (prev)
{
prev->flink = curr;
}
else
{
*list = curr;
}
curr->flink = next;
}
}
}
}
while (ptr);
}
struct variable_s *find_variable(const char *varname, struct variable_s *list)
{
while (list)
{
if (strcmp(varname, list->var) == 0)
{
return list;
}
list = list->flink;
}
return NULL;
}
