impr: Don't memory map files, never keep a write handle open for long

Closes #592

lib/libimhex/include/hex/helpers/file.hpp

@@ -8,12 +8,20 @@
 
 #include <hex/helpers/fs.hpp>
 
+#include <sys/stat.h>
+
 #if defined(OS_MACOS)
+    #include <unistd.h>
+    #include <sys/fcntl.h>
+
     #define off64_t     off_t
     #define fopen64     fopen
     #define fseeko64    fseek
     #define ftello64    ftell
     #define ftruncate64 ftruncate
+#elif defined(OS_LINUX)
+    #include <unistd.h>
+    #include <fcntl.h>
 #endif
 
 namespace hex::fs {
@@ -65,6 +73,8 @@ namespace hex::fs {
 
         void disableBuffering();
 
+        std::optional<struct stat> getFileInfo();
+
     private:
         FILE *m_file;
         std::fs::path m_path;

lib/libimhex/source/helpers/file.cpp

@@ -168,4 +168,18 @@ namespace hex::fs {
         std::setvbuf(this->m_file, nullptr, _IONBF, 0);
     }
 
+    std::optional<struct stat> File::getFileInfo() {
+        struct stat fileInfo = { };
+
+        #if defined(OS_WINDOWS)
+            if (wstat(this->m_path.c_str(), &fileInfo) != 0)
+                return std::nullopt;
+        #else
+            if (stat(hex::toUTF8String(this->m_path).c_str(), &fileInfo) != 0)
+                return std::nullopt;
+        #endif
+
+        return fileInfo;
+    }
+
 }

lib/libimhex/source/providers/provider.cpp

@@ -114,6 +114,10 @@ namespace hex::prv {
         for (auto &[patchAddress, patch] : getPatches()) {
             this->writeRaw(patchAddress - this->getBaseAddress(), &patch, 1);
         }
+
+        if (!this->isWritable())
+            return;
+
         this->markDirty();
 
         this->m_patches.emplace_back();