/* ====================================================================
* Copyright 1999 Web Juice, LLC. All rights reserved.
*
* varlist.c
*
* Functions for manipulating the variable list structure in the template
* library.
*
* ==================================================================== */
#include <string.h>
#include <stdlib.h>
#include <varlist.h>
#include <template.h>
/* ====================================================================
* NAME: varlist_init
*
* DESCRIPTION: Initializes and returns a pointer to a new varlist
* structure.
*
* RETURN VALUES: Returns NULL if the memory allocation fails; otherwise
* returns a pointer to a varlist structure.
*
* BUGS: Hopefully none.
* ==================================================================== */
varlist_p
varlist_init(
void
)
{
varlist_p variable_list;
variable_list = (varlist_p)
malloc
(
sizeof
(varlist));
if
(variable_list == NULL)
{
template_errno = TMPL_EMALLOC;
return
NULL;
}
variable_list->next = NULL;
variable_list->name = NULL;
variable_list->value = NULL;
return
(variable_list);
}
/* ====================================================================
* NAME: varlist_destroy
*
* DESCRIPTION: Frees up all memory associated with a varlist.
*
* RETURN VALUES: None.
*
* BUGS: Because a free()d pointer still *looks* valid, it is
* difficult to protect against the problems that arise
* if the user calls this function too early.
* ==================================================================== */
void
varlist_destroy(varlist_p variable_list)
{
varlist_p next;
if
(variable_list == NULL)
{
return
;
}
next = variable_list->next;
variable_list->next = NULL;
if
(variable_list->name != NULL)
{
free
(variable_list->name);
}
if
(variable_list->value != NULL)
{
free
(variable_list->value);
}
free
(variable_list);
varlist_destroy(next);
}
/* ====================================================================
* NAME: varlist_get_value
*
* DESCRIPTION: Returns the value of the variable stored under the given
* name, if it exists.
*
* RETURN VALUES: This function will return NULL if there are any problems
* or if there is no value. It returns a string containing
* the value on success.
*
* BUGS: Hopefully none.
* ==================================================================== */
char
*
varlist_get_value(varlist_p variable_list,
char
*name)
{
varlist_p current = variable_list;
while
(current != NULL)
{
if
((current->name != NULL) && (current->value != NULL)
&& (
strcmp
(current->name, name) == 0))
{
return
(current->value);
}
current = current->next;
}
template_errno = TMPL_ENOVALUE;
return
NULL;
}
/* ====================================================================
* NAME: varlist_set_value
*
* DESCRIPTION: Set a variable in the given varlist to be equal to
* the value given.
*
* RETURN VALUES: Returns 0 if there's any trouble. Returns 1 if the
* variable was successfully set.
*
* BUGS: Hopefully none.
* ==================================================================== */
int
varlist_set_value(varlist_p *variable_list,
char
*name,
char
*value)
{
varlist_p
new
= NULL;
int
length;
/* Make sure that the name and value aren't NULL */
if
((name == NULL) || (value == NULL))
{
template_errno = TMPL_ENULLARG;
return
0;
}
new
= varlist_init();
if
(
new
== NULL)
{
return
0;
}
length =
strlen
(name);
new
->name = (
char
*)
malloc
(length + 1);
strncpy
(
new
->name, name, length);
new
->name[length] =
'\0'
;
length =
strlen
(value);
new
->value = (
char
*)
malloc
(length + 1);
strncpy
(
new
->value, value, length);
new
->value[length] =
'\0'
;
new
->next = *variable_list;
*variable_list =
new
;
return
1;
}