feat: Add band module for memory and variable management

src/band.c

@@ -0,0 +1,116 @@
+#include <stdbool.h>
+#include <stdlib.h>
+
+#include "band.h"
+#include "list.h"
+#include "dict.h"
+#include "alloc.h"
+
+band_t* band_init(void) {
+	band_t* band = safe_malloc(sizeof(band_t));
+	band->regions = list_new(region_t);
+	band->variables = dict_new();
+	band->addr_lookup = list_new(region_t);
+	return band;
+}
+
+region_t* band_region_for_addr(band_t* band, band_addr_t addr) {
+	size_t band_length = list_size(band->band);
+	if (band_length >= addr) {
+		return NULL;
+	} else {
+		return band->band[addr];
+	}
+}
+
+region_t* band_region_for_var(band_t* band, const char* variable) {
+	return dict_get(band->variables, variable);
+}
+
+band_addr_t band_find_gap(band_t* band, size_t size) {
+	size_t band_size = list_size(band->band);
+
+	size_t current = 0;
+	for (size_t i = 0; i < band_size; i++) {
+		if (band->band[i] == NULL) {
+			current++;
+			if (current >= size) {
+				return i - current;
+			}
+		} else {
+			current = 0;
+		}
+	}
+
+	size_t missing_size = size - current;
+
+	band->band = list_ensure_space(band->band, sizeof(region_t*), missing_size);
+	
+	return band_size - current;
+}
+
+size_t band_find_empty_region_index(band_t* band) {
+	size_t regions_size = list_size(band->regions);
+	for (size_t i = 0; i < regions_size; i++) {
+		if (band->regions[i] == NULL) {
+			return i;
+		}
+	}
+
+	band->regions = list_ensure_space(band->regions, sizeof(region_t*), 1);
+	return regions_size;
+}
+
+region_t* band_allocate_region(band_t* band, size_t size) {
+	region_t* region = safe_malloc(sizeof(region_t));
+	band_addr_t addr = band_find_gap(band, size);
+	size_t regions_index = band_find_empty_region_index(band);
+
+	region->start = addr;
+	region->size = size;
+	region->index = regions_index;
+
+	band->regions[regions_index] = region;
+	for (size_t i = 0; i < size; i++) {
+		band->band[addr + i] = region;
+	}
+
+	return region;
+}
+
+region_t* band_allocate_var(band_t* band, size_t size, const char* variable) {
+	region_t* region = band_allocate_region(band, size);
+
+	region->variable = variable;
+	region->is_temp = false;
+
+	dict_put(band->variables, variable, region);
+
+	return region;
+}
+
+region_t* band_allocate_tmp(band_t* band, size_t size) {
+	region_t* region = band_allocate_region(band, size);
+
+	region->variable = NULL;
+	region->is_temp = true;
+
+	return region;
+}
+
+void band_region_free(band_t* band, region_t* region) {
+	band->regions[region->index] = NULL;
+	for (size_t i = 0; i < region->size; i++) {
+		band->band[region->start + i] = NULL;
+	}
+
+	if (region->variable) {
+		dict_remove(band->variables, region->variable);
+	}
+
+	free(region);
+}
+
+void band_region_free_raw(band_t* band, band_addr_t addr) {
+	band_free(band, band->band[addr]);
+}

src/band.h

@@ -0,0 +1,38 @@
+#ifndef BAND_H
+#define BAND_H
+
+#include <stdbool.h>
+#include <stdlib.h>
+
+#include "list.h"
+#include "dict.h"
+
+typedef size_t band_addr_t;
+
+typedef struct {
+	band_addr_t start;
+	size_t index;
+	size_t size;
+	const char* variable;
+	bool is_temp;	
+} region_t;
+
+typedef struct {
+	region_t** regions;
+	dict_t* variables;
+	region_t** band;
+} band_t;
+
+band_t* band_init(void);
+
+region_t* band_region_for_addr(band_t*, band_addr_t);
+region_t* band_region_for_var(band_t*, const char*);
+
+region_t* band_allocate_var(band_t*, size_t, const char*);
+region_t* band_allocate_tmp(band_t*, size_t);
+
+void band_region_free(band_t*, region_t*);
+void band_region_free_raw(band_t*, band_addr_t);
+
+
+#endif