Multithread

Sources/data_map.h

@@ -0,0 +1,69 @@
+#pragma once
+
+#include <cstdint>
+#include <cstdio>
+
+#ifdef _WIN32
+#include <Windows.h>
+#else
+#include <sys/mman.h>
+#include <unistd.h>
+#endif
+
+struct DataMap {
+    void* data = nullptr;
+    size_t size = 0;
+
+#ifdef _WIN32
+    HANDLE map_handle = nullptr;
+#endif
+
+    bool map_from_reader(void* reader_data, size_t reader_size) {
+        size = reader_size;
+        if (size == 0) return true;
+#ifdef _WIN32
+        HANDLE file_handle = reader_data;
+        map_handle = CreateFileMappingA(file_handle, nullptr, PAGE_READONLY, 0, 0, nullptr);
+        if (!map_handle) return false;
+        data = MapViewOfFile(map_handle, FILE_MAP_READ, 0, 0, 0);
+        if (!data) {
+            CloseHandle(map_handle);
+            map_handle = nullptr;
+            return false;
+        }
+        return true;
+#else
+        int fd = fileno((FILE*)reader_data);
+        if (fd < 0) return false;
+        data = mmap(nullptr, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+        if (data == MAP_FAILED) {
+            data = nullptr;
+            return false;
+        }
+        return true;
+#endif
+    }
+
+    void close() {
+        if (data) {
+#ifdef _WIN32
+            UnmapViewOfFile(data);
+#else
+            munmap(data, size);
+#endif
+            data = nullptr;
+        }
+#ifdef _WIN32
+        if (map_handle) { CloseHandle(map_handle); map_handle = nullptr; }
+#endif
+        size = 0;
+    }
+
+    ~DataMap() { close(); }
+};
+
+inline void delete_map(void* ptr, size_t length, void* deleter_data) {
+    DataMap* dm = static_cast<DataMap*>(deleter_data);
+    if (dm) dm->close();
+    delete dm;
+}