miller/c/containers/bind_stack.c
2016-09-10 23:39:15 -04:00

80 lines
2.5 KiB
C

#include <stdlib.h>
#include "lib/mlrutil.h"
#include "lib/mlr_globals.h"
#include "containers/bind_stack.h"
#define INITIAL_SIZE 32
// ----------------------------------------------------------------
bind_stack_t* bind_stack_alloc() {
bind_stack_t* pstack = mlr_malloc_or_die(sizeof(bind_stack_t));
pstack->num_used = 0;
pstack->num_allocated = INITIAL_SIZE;
pstack->pframes = mlr_malloc_or_die(pstack->num_allocated * sizeof(bind_stack_frame_t));
memset(pstack->pframes, 0, pstack->num_allocated * sizeof(bind_stack_frame_t));
return pstack;
}
// ----------------------------------------------------------------
void bind_stack_free(bind_stack_t* pstack) {
if (pstack == NULL)
return;
free(pstack->pframes);
free(pstack);
}
// ----------------------------------------------------------------
static void bind_stack_push_fenced_aux(bind_stack_t* pstack, lhmsmv_t* bindings, int fenced) {
if (pstack->num_used >= pstack->num_allocated) {
pstack->num_allocated += INITIAL_SIZE;
pstack->pframes = mlr_realloc_or_die(pstack->pframes,
pstack->num_allocated * sizeof(bind_stack_frame_t));
}
pstack->pframes[pstack->num_used].bindings = bindings;
pstack->pframes[pstack->num_used].fenced = fenced;
pstack->num_used++;
}
void bind_stack_push(bind_stack_t* pstack, lhmsmv_t* bindings) {
bind_stack_push_fenced_aux(pstack, bindings, FALSE);
}
void bind_stack_push_fenced(bind_stack_t* pstack, lhmsmv_t* bindings) {
bind_stack_push_fenced_aux(pstack, bindings, TRUE);
}
// ----------------------------------------------------------------
void bind_stack_pop(bind_stack_t* pstack) {
if (pstack->num_used <= 0) {
fprintf(stderr, "%s: internal coding error detected in file %s at line %d.\n",
MLR_GLOBALS.bargv0, __FILE__, __LINE__);
exit(1);
}
pstack->num_used--;
}
// ----------------------------------------------------------------
mv_t* bind_stack_resolve(bind_stack_t* pstack, char* key) {
for (int i = pstack->num_used - 1; i >= 0; i--) {
mv_t* pval = lhmsmv_get(pstack->pframes[i].bindings, key);
if (pval != NULL)
return pval;
if (pstack->pframes[i].fenced)
break;
}
return NULL;
}
// ----------------------------------------------------------------
void bind_stack_print(bind_stack_t* pstack) {
printf("BIND STACK BEGIN (#frames %d):\n", pstack->num_used);
for (int i = pstack->num_used - 1; i >= 0; i--) {
printf("-- FRAME %d (fenced:%d):\n", i, pstack->pframes[i].fenced);
lhmsmv_dump(pstack->pframes[i].bindings);
}
printf("BIND STACK END\n");
}