Version 1.08 with public source code release.

src/main/capnhook/hook/iohook.h

@@ -0,0 +1,90 @@
+/**
+ * Hook module for hooking I/O related calls, e.g. open, read, write etc.
+ *
+ * Based on original capnhook code for windows by decafcode:
+ * https://github.com/decafcode/capnhook
+ */
+#ifndef CAPNHOOK_IOHOOK_H
+#define CAPNHOOK_IOHOOK_H
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include "capnhook/hook/iobuf.h"
+
+/**
+ * Available operations to hook
+ */
+enum cnh_iohook_irp_op {
+    CNH_IOHOOK_IRP_OP_OPEN = 0,
+    CNH_IOHOOK_IRP_OP_FDOPEN = 1,
+    CNH_IOHOOK_IRP_OP_CLOSE = 2,
+    CNH_IOHOOK_IRP_OP_READ = 3,
+    CNH_IOHOOK_IRP_OP_WRITE = 4,
+    CNH_IOHOOK_IRP_OP_SEEK = 5,
+    CNH_IOHOOK_IRP_OP_IOCTL = 6,
+};
+
+/**
+ * I/O request packet
+ */
+struct cnh_iohook_irp {
+    enum cnh_iohook_irp_op op;
+    size_t next_handler;
+    int fd;
+    const char *open_filename;
+    int open_flags;
+    int fdopen_fd;
+    const char* fdopen_mode;
+    FILE* fdopen_res;
+    struct cnh_iobuf read;
+    struct cnh_const_iobuf write;
+    int seek_origin;
+    int64_t seek_offset;
+    uint64_t seek_pos;
+    int ioctl_req;
+    struct cnh_iobuf ioctl;
+};
+
+/**
+ * Hook function type
+ */
+typedef enum cnh_result (*cnh_iohook_fn_t)(struct cnh_iohook_irp *irp);
+
+/**
+ * Add a new hook handler to the hook module.
+ * The handler added is getting called on every hooked operation.
+ *
+ * @param fn Pointer to hook function to add
+ * @return Result/error code if hooking was successful
+ */
+enum cnh_result cnh_iohook_push_handler(cnh_iohook_fn_t fn);
+
+/**
+ * Invoke the next hooked function registered in the hook module.
+ * Call this from your hook handler if you want to pass on execution to further
+ * hooked calls reaching the original function at the end of the hook chain.
+ *
+ * @param irp I/O request package to dispatch
+ * @return Result of the following function dispatching the request package
+ */
+enum cnh_result cnh_iohook_invoke_next(struct cnh_iohook_irp *irp);
+
+/**
+ * Create a dummy file handle. Use this function for file access virtualization.
+ * Do not execute real operations on the handle returned.
+ *
+ * @return Actual file handle instance pointing to a dummy endpoint.
+ */
+int cnh_iohook_open_dummy_fd();
+
+/**
+ * Close a dummy file handle. Make sure to free your previously allocated handles
+ * to avoid resource leaks. Do not free them using the real close function.
+ *
+ * @param file Dummy file handle to free
+ */
+void cnh_iohook_close_dummy_fd(int fd);
+
+#endif