Initial commit

4 files changed, 72 insertions, 0 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
new file mode 100644
index 0000000..e09c4a2
--- /dev/null
+++ b/src/CMakeLists.txt
@@ -0,0 +1,8 @@
+add_subdirectory(fs)
+
+add_executable(extsh
+  extsh.cpp
+  )
+target_link_libraries(extsh
+  extfs
+  )
diff --git a/src/extsh.cpp b/src/extsh.cpp
new file mode 100644
index 0000000..477f6c8
--- /dev/null
+++ b/src/extsh.cpp
@@ -0,0 +1,19 @@
+#include "fs/extfs.hpp"
+
+#include <iostream>
+#include <string>
+
+int main(int argc, char const * argv[])
+  {
+  auto const & path = [&]{ return std::string{argc > 1 ? argv[1] : "vdisk.img"}; }();
+  auto const & disk = fs::extfs{path};
+
+  if(disk)
+    {
+    std::clog << "[EXT2] Successfully opened ext*fs at: '" << path << "'\n";
+    }
+  else
+    {
+    std::clog << "[EXT2] Failed to open ext*fs at: '" << path << "'\n";
+    }
+  }
diff --git a/src/fs/CMakeLists.txt b/src/fs/CMakeLists.txt
new file mode 100644
index 0000000..3ca33b8
--- /dev/null
+++ b/src/fs/CMakeLists.txt
@@ -0,0 +1,10 @@
+if(EXTFS_BUILD_STATIC)
+  set(LIBRARY_TYPE "STATIC")
+else()
+  set(LIBRARY_TYPE "SHARED")
+endif()
+
+add_library(extfs
+  ${LIBRARY_TYPE}
+  extfs.cpp
+  )
diff --git a/src/fs/extfs.cpp b/src/fs/extfs.cpp
new file mode 100644
index 0000000..19c294b
--- /dev/null
+++ b/src/fs/extfs.cpp
@@ -0,0 +1,35 @@
+#include "fs/detail/superblock.hpp"
+#include "fs/extfs.hpp"
+
+#include <fstream>
+#include <string>
+
+namespace
+  {
+  auto constexpr kPrimarySuperblockLocation = 1024;
+  auto constexpr kExtfsMagic = 0xef53;
+
+  auto read_superblock(std::fstream & stream, fs::detail::extfs_superblock & superblock)
+    {
+    auto const originalPosition = stream.tellg();
+    stream.seekg(kPrimarySuperblockLocation);
+    stream.read(reinterpret_cast<char *>(&superblock), sizeof(fs::detail::extfs_superblock));
+    stream.seekg(originalPosition);
+    }
+  }
+
+namespace fs
+  {
+
+  extfs::extfs(std::string const & path, extfs::mode const openMode) :
+    m_stream{path, std::ios::binary | (openMode == mode::read_only ? std::ios::in : std::ios::in | std::ios::out)}
+    {
+    read_superblock(m_stream, m_primarySuperblock);
+    }
+
+  extfs::operator bool() const
+    {
+    return m_stream && m_primarySuperblock.magic_number == kExtfsMagic;
+    }
+
+  }