fix is_block_device check, add device_inode and non-block device tests

4 files changed, 143 insertions, 3 deletions

diff --git a/kernel/CMakeLists.txt b/kernel/CMakeLists.txt
index df20704..53ed107 100644
--- a/kernel/CMakeLists.txt
+++ b/kernel/CMakeLists.txt
@@ -130,6 +130,7 @@ else()
 
         # Filesystem Subsystem Tests
         "src/filesystem/dentry.tests.cpp"
+        "src/filesystem/device_inode.tests.cpp"
 
         # Storage Subsystem Tests
         "src/devices/block_device_utils.tests.cpp"
diff --git a/kernel/src/devices/block_device_utils.cpp b/kernel/src/devices/block_device_utils.cpp
index a1fd5e3..59e9b97 100644
--- a/kernel/src/devices/block_device_utils.cpp
+++ b/kernel/src/devices/block_device_utils.cpp
@@ -31,12 +31,13 @@ namespace kernel::devices::block_device_utils
       return 0;
     }
 
-    auto * block_dev = static_cast<devices::block_device *>(device.get());
-    if (block_dev == nullptr)
+    if (!device->is_block_device())
     {
       kapi::system::panic("[FILESYSTEM] device_file: expected block_device.");
     }
 
+    auto * block_dev = static_cast<devices::block_device *>(device.get());
+
     size_t const block_size = block_dev->block_size();
     size_t const capacity = block_dev->capacity();
 
diff --git a/kernel/src/devices/block_device_utils.tests.cpp b/kernel/src/devices/block_device_utils.tests.cpp
index 5f27a9b..f78e477 100644
--- a/kernel/src/devices/block_device_utils.tests.cpp
+++ b/kernel/src/devices/block_device_utils.tests.cpp
@@ -2,6 +2,7 @@
 
 #include "kernel/test_support/cpu.hpp"
 #include "kernel/test_support/devices/block_device.hpp"
+#include "kernel/test_support/devices/character_device.hpp"
 
 #include <kstd/memory>
 #include <kstd/print>
@@ -186,4 +187,33 @@ SCENARIO("writing to a block device using block_device_utils", "[devices][block_
       }
     }
   }
-}
\ No newline at end of file
+}
+
+SCENARIO("block_device_utils with a non-block device", "[devices][block_device_utils]")
+{
+  GIVEN("a non-block device")
+  {
+    auto device = kstd::make_shared<kernel::tests::devices::character_device>(0, 0, "test_character_device");
+
+    WHEN("attempting to read from the non-block device using block_device_utils")
+    {
+      kstd::vector<uint8_t> read_buffer(512);
+      THEN("the system panics")
+      {
+        REQUIRE_THROWS_AS(kernel::devices::block_device_utils::read(device, read_buffer.data(), 0, read_buffer.size()),
+                          kernel::tests::cpu::halt);
+      }
+    }
+
+    WHEN("attempting to write to the non-block device using block_device_utils")
+    {
+      kstd::vector<uint8_t> write_buffer(512);
+      THEN("the system panics")
+      {
+        REQUIRE_THROWS_AS(
+            kernel::devices::block_device_utils::write(device, write_buffer.data(), 0, write_buffer.size()),
+            kernel::tests::cpu::halt);
+      }
+    }
+  }
+}
diff --git a/kernel/src/filesystem/device_inode.tests.cpp b/kernel/src/filesystem/device_inode.tests.cpp
new file mode 100644
index 0000000..4e31812
--- /dev/null
+++ b/kernel/src/filesystem/device_inode.tests.cpp
@@ -0,0 +1,108 @@
+#include "kernel/filesystem/device_inode.hpp"
+
+#include "kernel/test_support/cpu.hpp"
+#include "kernel/test_support/devices/block_device.hpp"
+#include "kernel/test_support/devices/character_device.hpp"
+
+#include <kstd/memory>
+#include <kstd/print>
+#include <kstd/vector>
+
+#include <catch2/catch_test_macros.hpp>
+
+#include <cstddef>
+#include <cstdint>
+
+SCENARIO("Device inode construction", "[filesystem][device_inode]")
+{
+  GIVEN("a block device")
+  {
+    auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "test_block_device", 512, 3 * 512);
+
+    WHEN("constructing a device inode with the block device")
+    {
+      auto inode = kernel::filesystem::device_inode{device};
+
+      THEN("the device inode has the correct device")
+      {
+        REQUIRE(inode.device() == device);
+      }
+
+      THEN("the device inode has the correct kind")
+      {
+        REQUIRE(inode.is_device());
+        REQUIRE_FALSE(inode.is_directory());
+        REQUIRE_FALSE(inode.is_regular());
+      }
+    }
+
+    WHEN("constructing a device inode with a null device")
+    {
+      THEN("the constructor panics")
+      {
+        REQUIRE_THROWS_AS((kernel::filesystem::device_inode{nullptr}), kernel::tests::cpu::halt);
+      }
+    }
+  }
+}
+
+SCENARIO("Device inode read/write", "[filesystem][device_inode]")
+{
+  GIVEN("a block device and a device inode for that device")
+  {
+    auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "test_block_device", 512, 3 * 512);
+    auto inode = kernel::filesystem::device_inode{device};
+
+    WHEN("writing to the device inode")
+    {
+      kstd::vector<uint8_t> write_buffer(1024);
+      for (size_t i = 0; i < write_buffer.size(); ++i)
+      {
+        write_buffer[i] = static_cast<uint8_t>(i % 256);
+      }
+
+      auto bytes_written = inode.write(write_buffer.data(), 256, write_buffer.size());
+
+      THEN("the correct number of bytes is written")
+      {
+        REQUIRE(bytes_written == 1024);
+      }
+
+      THEN("the data written matches the data read back from the device inode")
+      {
+        kstd::vector<uint8_t> read_buffer(1024);
+        auto bytes_read = inode.read(read_buffer.data(), 256, read_buffer.size());
+
+        REQUIRE(bytes_read == write_buffer.size());
+        REQUIRE(read_buffer == write_buffer);
+      }
+    }
+  }
+}
+
+SCENARIO("Device inode read/write with a non-block device", "[filesystem][device_inode]")
+{
+  GIVEN("a non-block device and a device inode for that device")
+  {
+    auto device = kstd::make_shared<kernel::tests::devices::character_device>(0, 0, "test_character_device");
+    auto inode = kernel::filesystem::device_inode{device};
+
+    WHEN("reading from the device inode")
+    {
+      kstd::vector<uint8_t> read_buffer(512);
+      THEN("the system panics")
+      {
+        REQUIRE_THROWS_AS(inode.read(read_buffer.data(), 0, read_buffer.size()), kernel::tests::cpu::halt);
+      }
+    }
+
+    WHEN("writing to the device inode")
+    {
+      kstd::vector<uint8_t> write_buffer(512);
+      THEN("the system panics")
+      {
+        REQUIRE_THROWS_AS(inode.write(write_buffer.data(), 0, write_buffer.size()), kernel::tests::cpu::halt);
+      }
+    }
+  }
+}