244 lines
7.0 KiB
C

/* This file is part of the Project Athena Zephyr Notification System.
* It is one of the source files comprising zwgc, the Zephyr WindowGram
* client.
*
* Created by: Marc Horowitz <marc@athena.mit.edu>
*
* $Id$
*
* Copyright (c) 1989 by the Massachusetts Institute of Technology.
* For copying and distribution information, see the file
* "mit-copyright.h".
*/
#include <sysdep.h>
#if (!defined(lint) && !defined(SABER))
static const char rcsid_variables_c[] = "$Id$";
#endif
#include <zephyr/mit-copyright.h>
/****************************************************************************/
/* */
/* Module containing code to deal with description langauge variables: */
/* */
/****************************************************************************/
#include "new_memory.h"
#include "notice.h"
#include "string_dictionary_aux.h"
#include "variables.h"
/*
* fields_data[_length] - these point to the field data that the number
* variables were last set to using
* var_set_number_variables_to_fields.
*/
static char *fields_data;
static int fields_data_length = 0;
/*
* [non_]number_variable_dict - contains the values of all the [non-]number
* variables that have been set since the last
* var_clear_all_variables call or (for numbers
* only) var_set_number_variables_to_fields call.
*/
static string_dictionary non_number_variable_dict = NULL;
static string_dictionary number_variable_dict = NULL;
/*
* Internal Routine:
*
* int is_digits(string text)
* Effects: Returns true iff text matches [0-9]*. ("" matches...)
*/
static int
is_digits(string text)
{
for (; *text; text++)
if (!isdigit(*text))
return(0);
return(1);
}
/*
* Internal Routine:
*
* int is_number_variable(string text)
* Effects: Returns true iff text matches [0-9]+.
*/
#define is_number_variable(x) (isdigit(*(x)) && is_digits((x)))
/*
* void var_clear_all_variables()
* Requires: This routine must be called before any other
* var module routine is called.
* Modifies: All description language variables
* Effects: Sets all description langauge variables to "".
*/
void
var_clear_all_variables(void)
{
if (non_number_variable_dict) {
string_dictionary_SafeDestroy(non_number_variable_dict);
string_dictionary_SafeDestroy(number_variable_dict);
}
non_number_variable_dict = string_dictionary_Create(101);
number_variable_dict = string_dictionary_Create(11);
fields_data_length = 0;
}
/*
* string var_get_variable(string name)
* Requires: var_clear_all_variables has been called
* Effects: Returns the value of the description langauge variable
* named name. The returned string is read-only and is
* guarenteed to last only until the next var module
* call. DO NOT FREE THIS STRING.
*/
string
var_get_variable(string name)
{
char *result;
int field_to_get;
static string last_get_field_call_result = NULL;
if (is_number_variable(name)) {
result = string_dictionary_Fetch(number_variable_dict, name);
if (result)
return(result);
/*
* Convert name to an integer avoiding overflow:
*/
while (*name=='0')
name++;
if (strlen(name)>12)
field_to_get = 0; /* no way we'll have > 1 trillian fields... */
else
field_to_get = atoi(name);
if (!field_to_get)
return("");
if (last_get_field_call_result)
free(last_get_field_call_result);
last_get_field_call_result = get_field(fields_data,
fields_data_length,
field_to_get);
return(last_get_field_call_result);
}
if (!(result = string_dictionary_Fetch(non_number_variable_dict, name)))
result = "";
return(result);
}
/*
* void var_set_variable(string name, value)
* Requires: var_clear_all_variables has been called
* Modifies: The value of description langauge variable
* named name.
* Effects: Sets the description langauge variable named name
* to have the value value.
*/
void
var_set_variable(string name,
string value)
{
string_dictionary_Set(is_number_variable(name) ? number_variable_dict
: non_number_variable_dict, name, value);
}
/*
* void var_set_variable_to_number(string name; int number)
* Requires: var_clear_all_variables has been called
* Modifies: The value of description langauge variable
* named name.
* Effects: Sets the description langauge variable named name
* to have as its value number's ascii representation.
*/
void
var_set_variable_to_number(string name,
int number)
{
char buffer[20];
sprintf(buffer, "%d", number);
var_set_variable(name, buffer);
}
/*
* void var_set_variable_then_free_value(string name, value)
* Requires: var_clear_all_variables has been called, value is
* on the heap.
* Modifies: The value of description langauge variable
* named name, value
* Effects: Sets the description langauge variable named name
* to have the value value then frees value. This
* routine is slightly faster than calling var_set_variable
* then freeing value. It is provided mainly for
* convenience reasons.
*/
void
var_set_variable_then_free_value(string name,
string value)
{
string_dictionary_binding *binding;
int exists;
#ifdef DEBUG_MEMORY
if (!memory__on_heap_p(value))
abort(); /* <<<>>> */
#endif
if (is_number_variable(name)) {
var_set_variable(name, value);
free(value);
return;
}
binding = string_dictionary_Define(non_number_variable_dict, name,
&exists);
if (exists)
free(binding->value);
binding->value = value;
}
/*
* void var_set_number_variables_to_fields(char *data, int length)
* Requires: var_clear_all_variables has been called
* Modifies: All numeric description language variables
* Effects: Treats data[0]..data[length-1] as a series of
* null-seperated fields. Sets $<number> (<number>
* here means [0-9]+ to field # <number> in data.
* Field 0 is defined to be "" as are all field #'s
* greater than the number of fields in data.
* Data[0]..data[length-1] must not be changed (or freed)
* until either this call is made again with different
* data or var_clear_all_variables is called.
*/
void
var_set_number_variables_to_fields(char *data,
int length)
{
fields_data = data;
fields_data_length = length;
string_dictionary_SafeDestroy(number_variable_dict);
number_variable_dict = string_dictionary_Create(11);
}