#include "std.h"
#include "replace_program.h"
#include "simul_efun.h"
#include "efun_protos.h"
/*
* replace_program.c
* replaces the program in a running object with one of the programs
* it inherits, in order to save memory.
* Ported from Amylaars LP 3.2 driver
*/
replace_ob_t *obj_list_replace = 0;
static program_t *search_inherited (char *, program_t *, int *);
static replace_ob_t *retrieve_replace_program_entry (void);
int replace_program_pending (object_t * ob)
{
replace_ob_t *r_ob;
for (r_ob = obj_list_replace; r_ob; r_ob = r_ob->next) {
if (r_ob->ob == ob)
return 1;
}
return 0;
}
void replace_programs (void)
{
replace_ob_t *r_ob, *r_next;
int i, num_fewer, offset;
svalue_t *svp;
debug(d_flag, ("start of replace_programs"));
for (r_ob = obj_list_replace; r_ob; r_ob = r_next) {
program_t *old_prog;
num_fewer = r_ob->ob->prog->num_variables_total - r_ob->new_prog->num_variables_total;
debug(d_flag, ("%d less variables\n", num_fewer));
tot_alloc_object_size -= num_fewer * sizeof(svalue_t[1]);
if ((offset = r_ob->var_offset)) {
svp = r_ob->ob->variables;
/* move our variables up to the top */
for (i = 0; i < r_ob->new_prog->num_variables_total; i++) {
free_svalue(svp, "replace_programs");
*svp = *(svp + offset);
*(svp + offset) = const0u;
svp++;
}
/* free the rest */
for (i = 0; i < num_fewer; i++) {
free_svalue(svp, "replace_programs");
*svp++ = const0u;
}
} else {
/* We just need to remove the last num_fewer variables */
svp = &r_ob->ob->variables[r_ob->new_prog->num_variables_total];
for (i = 0; i < num_fewer; i++) {
free_svalue(svp, "replace_programs");
*svp++ = const0u;
}
}
if (r_ob->ob->replaced_program) {
FREE_MSTR(r_ob->ob->replaced_program);
r_ob->ob->replaced_program = 0;
}
r_ob->ob->replaced_program = string_copy(r_ob->new_prog->filename, "replace_programs");
reference_prog(r_ob->new_prog, "replace_programs");
old_prog = r_ob->ob->prog;
r_ob->ob->prog = r_ob->new_prog;
r_next = r_ob->next;
free_prog(&old_prog);
debug(d_flag, ("program freed."));
#ifndef NO_SHADOWS
if (r_ob->ob->shadowing) {
/*
* The master couldn't decide if it's a legal shadowing before
* the program was actually replaced. It is possible that the
* blueprint to the replacing program is already destructed, and
* it's source changed. On the other hand, if we called the
* master now, all kind of volatile data structures could result,
* even new entries for obj_list_replace. This would eventually
* require to reference it, and all the lrpp's , in
* check_a_lot_ref_counts() and garbage_collection() . Being able
* to use replace_program() in shadows is hardly worth this
* effort. Thus, we simply stop the shadowing.
*/
r_ob->ob->shadowing->shadowed = r_ob->ob->shadowed;
if (r_ob->ob->shadowed) {
r_ob->ob->shadowed->shadowing = r_ob->ob->shadowing;
r_ob->ob->shadowed = 0;
}
r_ob->ob->shadowing = 0;
}
#endif
FREE((char *) r_ob);
}
obj_list_replace = (replace_ob_t *) 0;
debug(d_flag, ("end of replace_programs"));
}
#ifdef F_REPLACE_PROGRAM
static program_t *search_inherited (char * str, program_t * prg, int * offpnt)
{
program_t *tmp;
int i;
debug(d_flag, ("search_inherited started"));
debug(d_flag, ("searching for PRG(/%s) in PRG(/%s)", str, prg->filename));
debug(d_flag, ("num_inherited=%d\n", prg->num_inherited));
for (i = 0; i < prg->num_inherited; i++) {
debug(d_flag, ("index %d:", i));
debug(d_flag, ("checking PRG(/%s)", prg->inherit[i].prog->filename));
if (strcmp(str, prg->inherit[i].prog->filename) == 0) {
debug(d_flag, ("match found"));
*offpnt = prg->inherit[i].variable_index_offset;
return prg->inherit[i].prog;
} else if ((tmp = search_inherited(str, prg->inherit[i].prog,
offpnt))) {
debug(d_flag, ("deferred match found"));
*offpnt += prg->inherit[i].variable_index_offset;
return tmp;
}
}
debug(d_flag, ("search_inherited failed"));
return (program_t *) 0;
}
static replace_ob_t *retrieve_replace_program_entry (void)
{
replace_ob_t *r_ob;
for (r_ob = obj_list_replace; r_ob; r_ob = r_ob->next) {
if (r_ob->ob == current_object) {
return r_ob;
}
}
return 0;
}
void
f_replace_program (void)
{
replace_ob_t *tmp;
int name_len;
char *name, *xname;
program_t *new_prog;
int var_offset;
if (sp->type != T_STRING)
bad_arg(1, F_REPLACE_PROGRAM);
debug(d_flag, ("replace_program called"));
if (!current_object)
error("replace_program called with no current object\n");
if (current_object == simul_efun_ob)
error("replace_program on simul_efun object\n");
if (current_object->prog->func_ref)
error("cannot replace a program with function references.\n");
name_len = SVALUE_STRLEN(sp);
name = (char *) DMALLOC(name_len + 3, TAG_TEMPORARY, "replace_program");
xname = name;
strcpy(name, sp->u.string);
if (name[name_len - 2] != '.' || name[name_len - 1] != 'c')
strcat(name, ".c");
if (*name == '/')
name++;
new_prog = search_inherited(name, current_object->prog, &var_offset);
FREE(xname);
if (!new_prog) {
error("program to replace the current with has to be inherited\n");
}
if (!(tmp = retrieve_replace_program_entry())) {
tmp = ALLOCATE(replace_ob_t, TAG_TEMPORARY, "replace_program");
tmp->ob = current_object;
tmp->next = obj_list_replace;
obj_list_replace = tmp;
}
tmp->new_prog = new_prog;
tmp->var_offset = var_offset;
debug(d_flag, ("replace_program finished"));
free_string_svalue(sp--);
}
#endif
