refactor: MCP層をmcpc APIベースに刷新

- 独自JSON-RPC処理をmcpcへ置き換え
- 各MCPツールを個別ソースへ分離
- 共通コンテキストと登録処理を整理
- mcpc互換修正と統合テストを更新

2 files changed, 130 insertions, 0 deletions

diff --git a/src/base/allocator.c b/src/base/allocator.c
new file mode 100644
index 0000000..3a5c515
--- /dev/null
+++ b/src/base/allocator.c
@@ -0,0 +1,107 @@
+#define TINY_ALLOCATOR_IMPLEMENTATION
+#include "base/allocator.h"
+
+#include <stdint.h>
+#include <stdlib.h>
+
+static size_t fail_index = SIZE_MAX;
+static size_t calls;
+static size_t outstanding;
+
+static int
+should_fail(void)
+{
+  return calls++ == fail_index;
+}
+
+void *
+tiny_alloc(size_t size)
+{
+  void *result;
+  if (should_fail())
+    {
+      return NULL;
+    }
+  result = malloc(size);
+  if (result != NULL)
+    {
+      outstanding++;
+    }
+  return result;
+}
+
+void *
+tiny_calloc(size_t count, size_t size)
+{
+  void *result;
+  if ((size != 0 && count > SIZE_MAX / size) || should_fail())
+    {
+      return NULL;
+    }
+  result = calloc(count, size);
+  if (result != NULL)
+    {
+      outstanding++;
+    }
+  return result;
+}
+
+void *
+tiny_realloc(void *memory, size_t size)
+{
+  void *result;
+  if (size == 0)
+    {
+      tiny_free(memory);
+      return NULL;
+    }
+  if (should_fail())
+    {
+      return NULL;
+    }
+  result = realloc(memory, size);
+  if (result != NULL && memory == NULL)
+    {
+      outstanding++;
+    }
+  return result;
+}
+
+void
+tiny_free(void *memory)
+{
+  if (memory != NULL)
+    {
+      free(memory);
+      if (outstanding > 0)
+        {
+          outstanding--;
+        }
+    }
+}
+
+void
+tiny_allocator_reset(void)
+{
+  fail_index = SIZE_MAX;
+  calls = 0;
+}
+
+void
+tiny_allocator_fail_after(size_t allocation_index)
+{
+  fail_index = allocation_index;
+  calls = 0;
+}
+
+size_t
+tiny_allocator_call_count(void)
+{
+  return calls;
+}
+
+size_t
+tiny_allocator_outstanding(void)
+{
+  return outstanding;
+}
diff --git a/src/base/allocator.h b/src/base/allocator.h
new file mode 100644
index 0000000..626e294
--- /dev/null
+++ b/src/base/allocator.h
@@ -0,0 +1,23 @@
+#ifndef TINY_CONVMEM_BASE_ALLOCATOR_H
+#define TINY_CONVMEM_BASE_ALLOCATOR_H
+
+#include <stddef.h>
+
+void *tiny_alloc(size_t size);
+void *tiny_calloc(size_t count, size_t size);
+void *tiny_realloc(void *memory, size_t size);
+void tiny_free(void *memory);
+
+void tiny_allocator_reset(void);
+void tiny_allocator_fail_after(size_t allocation_index);
+size_t tiny_allocator_call_count(void);
+size_t tiny_allocator_outstanding(void);
+
+#ifndef TINY_ALLOCATOR_IMPLEMENTATION
+#define malloc tiny_alloc
+#define calloc tiny_calloc
+#define realloc tiny_realloc
+#define free tiny_free
+#endif
+
+#endif