Started implementing a boot-time memory manager

sandbox/memblock/main.c

@@ -1,7 +1,49 @@
 #include <stdio.h>
+#include <stddef.h>
+#include <inttypes.h>
+#include <sys/mman.h>
+#include "memblock.h"
+
+/* we're working with 4MiB of simulated system RAM */
+#define MEMORY_SIZE 0x400000ULL
 
 int main(int argc, const char **argv)
 {
-	printf("Hello, world\n");
+	void *system_memory = mmap(
+			NULL,
+			MEMORY_SIZE,
+			PROT_READ | PROT_WRITE,
+			MAP_PRIVATE | MAP_ANONYMOUS,
+			-1, 0);
+
+	if (system_memory == MAP_FAILED) {
+		perror("mmap");
+		fprintf(stderr, "cannot allocate simulated system RAM buffer");
+		return -1;
+	}
+
+	printf("allocated 0x%llx bytes of memory to act as system RAM at %p\n", MEMORY_SIZE, system_memory);
+
+	memblock_add(0, MEMORY_SIZE);
+
+	memblock_reserve(0x10000, 0x40000);
+	memblock_reserve(0x60000, 0x20000);
+	memblock_reserve(0x30000, 0x40000);
+
+	printf("memory regions:\n");
+	for (unsigned int i = 0; i < memblock.memory.count; i++) {
+		printf("\t%08" PRIxPTR "-%08" PRIxPTR "\n",
+				memblock.memory.regions[i].base,
+				memblock.memory.regions[i].limit);
+	}
+
+	printf("reserved regions:\n");
+	for (unsigned int i = 0; i < memblock.reserved.count; i++) {
+		printf("\t%08" PRIxPTR "-%08" PRIxPTR "\n",
+				memblock.reserved.regions[i].base,
+				memblock.reserved.regions[i].limit);
+	}
+
+	munmap(system_memory, MEMORY_SIZE);
 	return 0;
 }