/* ====================================================================
* Copyright 1999 Web Juice, LLC. All rights reserved.
*
* staglist.c
*
* Functions for manipulating the simple tag list structure in the
* template library.
*
* ==================================================================== */
#include <string.h>
#include <stdlib.h>
#include <template.h>
/* ====================================================================
* NAME: staglist_init
*
* DESCRIPTION: Initializes and returns a pointer to a new simple tag
* structure.
*
* RETURN VALUES: Returns NULL if the memory allocation fails; otherwise
* returns a pointer to a simple tag structure.
*
* BUGS: Hopefully none.
* ==================================================================== */
staglist_p
staglist_init(void)
{
staglist_p simple_tag_list;
simple_tag_list = (staglist_p)malloc(sizeof(staglist));
if (simple_tag_list == NULL)
{
template_errno = TMPL_EMALLOC;
return NULL;
}
simple_tag_list->name = NULL;
simple_tag_list->function = NULL;
simple_tag_list->next = NULL;
return(simple_tag_list);
}
/* ====================================================================
* NAME: staglist_destroy
*
* DESCRIPTION: Frees up all memory associated with a simple tag list
*
* 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
staglist_destroy(staglist_p simple_tag_list)
{
staglist_p next;
if (simple_tag_list == NULL)
{
return;
}
next = simple_tag_list->next;
simple_tag_list->next = NULL;
if (simple_tag_list->name != NULL)
{
free(simple_tag_list->name);
}
free(simple_tag_list);
staglist_destroy(next);
}
/* ====================================================================
* NAME: staglist_alias
*
* DESCRIPTION: Copy an existing tag to a new name.
*
* RETURN VALUES: Returns 0 upon failure; 1 on success.
*
* BUGS: Hopefully none.
* ==================================================================== */
int
staglist_alias(staglist_p *simple_tag_list, char *old_name, char *new_name)
{
staglist_p current = *simple_tag_list;
/* Make sure that neither name is NULL */
if ((old_name == NULL) || (new_name == NULL))
{
template_errno = TMPL_ENULLARG;
return 0;
}
/* Walk through the list to find old_name */
while (current != NULL)
{
if ((current->name != NULL) && (strcmp(current->name, old_name) == 0))
{
return staglist_register(simple_tag_list, new_name,
current->function);
}
current = current->next;
}
template_errno = TMPL_ENOSTAG;
return 0;
}
/* ====================================================================
* NAME: staglist_remove
*
* DESCRIPTION: Remove a tag.
*
* RETURN VALUES: None.
*
* BUGS: Hopefully none.
* ==================================================================== */
void
staglist_remove(staglist_p *simple_tag_list, char *name)
{
staglist_p current = *simple_tag_list;
staglist_p previous = NULL;
/* Make sure the name isn't NULL */
if (name == NULL)
{
template_errno = TMPL_ENULLARG;
return;
}
/* Make sure the pointer passed in wasn't NULL */
if (*simple_tag_list == NULL)
{
template_errno = TMPL_ENULLARG;
return;
}
while (current != NULL)
{
if ((current->name != NULL) && (strcmp(current->name, name) == 0))
{
break;
}
previous = current;
current = current->next;
}
/* The tag wasn't found */
if (current == NULL)
{
return;
}
/* Move a pointer to skip the found tag */
if (previous == NULL)
{
*simple_tag_list = current->next;
} else
{
previous->next = current->next;
}
/* Destroy the tag */
current->next = NULL;
if (current->name != NULL)
{
free(current->name);
}
free(current);
}
/* ====================================================================
* NAME: staglist_register
*
* DESCRIPTION: Register a new tag and associated function to call.
*
* RETURN VALUES: Returns 0 upon failure; 1 on success.
*
* BUGS: Hopefully none.
* ==================================================================== */
int
staglist_register(staglist_p *simple_tag_list, char *name,
void (*function)(context_p, char **, int, char**))
{
staglist_p new = NULL;
int length;
/* Make sure the function isn't NULL */
if (function == NULL)
{
template_errno = TMPL_ENULLARG;
return 0;
}
/* Make sure the name isn't NULL */
if (name == NULL)
{
template_errno = TMPL_ENULLARG;
return 0;
}
/* Make sure the pointer passed in wasn't NULL */
if (*simple_tag_list == NULL)
{
template_errno = TMPL_ENULLARG;
return 0;
}
new = staglist_init();
if (new == NULL)
{
return 0;
}
new->function = function;
length = strlen(name);
new->name = (char *)malloc(length + 1);
strncpy(new->name, name, length);
new->name[length] = '\0';
new->next = *simple_tag_list;
*simple_tag_list = new;
return 1;
}
/* ====================================================================
* NAME: staglist_exists
*
* DESCRIPTION: Find out whether a particular tag is a legitimate
* simple tag.
*
* RETURN VALUES: Returns 0 if there's a problem or if the name is not
* a valid simple tag, or 1 if the name is a valid tag.
*
* BUGS: Hopefully none.
* ==================================================================== */
int
staglist_exists(staglist_p simple_tag_list, char *name)
{
staglist_p current = simple_tag_list;
while (current != NULL)
{
if ((current->name != NULL) && (current->function != NULL)
&& (strcmp(current->name, name) == 0))
{
return 1;
}
current = current->next;
}
template_errno = TMPL_ENOSTAG;
return 0;
}
/* ====================================================================
* NAME: staglist_exec
*
* DESCRIPTION: Executes the function associated with a given tag.
*
* RETURN VALUES: Returns NULL if there's a problem or the string result
* of the function on success.
*
* BUGS: Hopefully none.
* ==================================================================== */
int
staglist_exec(staglist_p simple_tag_list, char *name, context_p ctx,
char **output, int argc, char **argv)
{
staglist_p current = simple_tag_list;
while (current != NULL)
{
if ((current->name != NULL) && (current->function != NULL)
&& (strcmp(current->name, name) == 0))
{
current->function(ctx, output, argc, argv);
return 1;
}
current = current->next;
}
template_errno = TMPL_ENOSTAG;
return 0;
}