init main app code

RpiLedBars/src/smi/VitualMemory.cpp

@@ -0,0 +1,37 @@
+#include "VitualMemory.hpp"
+
+#include <stdexcept>
+
+#include "utils.h"
+#include <fcntl.h>
+// #include <sys/ioctl.h>
+#include <stdint.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+VitualMemory::VitualMemory(void *addr, int size) {
+  int fd;
+
+  roundSize = PAGE_ROUNDUP(size);
+
+  if ((fd = open("/dev/mem", O_RDWR | O_SYNC | O_CLOEXEC)) < 0) {
+    throw std::runtime_error("Error: can't open /dev/mem, run using sudo");
+  }
+
+  mem = mmap(0, roundSize, PROT_WRITE | PROT_READ, MAP_SHARED, fd, (uint32_t)addr);
+  close(fd);
+
+#if _DEBUG
+  printf("Map %p -> %p\n", (void *)addr, mem);
+#endif // _DEBUG
+
+  if (mem == MAP_FAILED) {
+    throw std::runtime_error("Error: can't map memory");
+  }
+}
+
+VitualMemory::~VitualMemory() {
+  if (mem) {
+    munmap(mem, roundSize);
+  }
+}