Initial commit.

src/macros.h

@@ -0,0 +1,130 @@
+/*
+ * Macros to hook functions.
+ *
+ * Copyright (C) 2013  Simon Ruderich
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef MACROS_H
+#define MACROS_H 1
+
+/* Hook the function by creating a function with the same name. With
+ * LD_PRELOAD our function will be preferred. The original function is stored
+ * in a static variable (real_*). */
+
+#define _HOOK_PRE(type, name) \
+        int handle; \
+        type result; \
+        DLSYM_FUNCTION(real_ ## name, #name);
+#define _HOOK_PRE_FD(type, name, fd) \
+        _HOOK_PRE(type, name) \
+        handle = check_handle_fd(fd); \
+        if (handle) { \
+            handle_fd_pre(fd, handle); \
+        }
+#define _HOOK_PRE_FILE(type, name, file) \
+        _HOOK_PRE(type, name) \
+        handle = check_handle_fd(fileno(file)); \
+        if (handle) { \
+            handle_file_pre(file, handle); \
+        }
+/* Save and restore the errno to make sure we return the errno of the original
+ * function call. */
+#define _HOOK_POST_FD(fd) \
+        if (handle) { \
+            int saved_errno = errno; \
+            handle_fd_post(fd, handle); \
+            errno = saved_errno; \
+        } \
+        return result;
+#define _HOOK_POST_FILE(file) \
+        if (handle) { \
+            int saved_errno = errno; \
+            handle_file_post(file, handle); \
+            errno = saved_errno; \
+        } \
+        return result;
+
+
+#define HOOK_FD3(type, name, fd, type1, arg1, type2, arg2, type3, arg3) \
+    static type (*real_ ## name)(type1, type2, type3); \
+    type name(type1 arg1, type2 arg2, type3 arg3) { \
+        _HOOK_PRE_FD(type, name, fd) \
+        result = real_ ## name(arg1, arg2, arg3); \
+        _HOOK_POST_FD(fd) \
+    }
+
+#define HOOK_FILE1(type, name, file, type1, arg1) \
+    static type (*real_ ## name)(type1); \
+    type name(type1 arg1) { \
+        _HOOK_PRE_FILE(type, name, file) \
+        result = real_ ## name(arg1); \
+        _HOOK_POST_FILE(file) \
+    }
+#define HOOK_FILE2(type, name, file, type1, arg1, type2, arg2) \
+    static type (*real_ ## name)(type1, type2); \
+    type name(type1 arg1, type2 arg2) { \
+        _HOOK_PRE_FILE(type, name, file) \
+        result = real_ ## name(arg1, arg2); \
+        _HOOK_POST_FILE(file) \
+    }
+#define HOOK_FILE3(type, name, file, type1, arg1, type2, arg2, type3, arg3) \
+    static type (*real_ ## name)(type1, type2, type3); \
+    type name(type1 arg1, type2 arg2, type3 arg3) { \
+        _HOOK_PRE_FILE(type, name, file) \
+        result = real_ ## name(arg1, arg2, arg3); \
+        _HOOK_POST_FILE(file) \
+    }
+#define HOOK_FILE4(type, name, file, type1, arg1, type2, arg2, type3, arg3, type4, arg4) \
+    static type (*real_ ## name)(type1, type2, type3, type4); \
+    type name(type1 arg1, type2 arg2, type3 arg3, type4 arg4) { \
+        _HOOK_PRE_FILE(type, name, file) \
+        result = real_ ## name(arg1, arg2, arg3, arg4); \
+        _HOOK_POST_FILE(file) \
+    }
+
+#define HOOK_VAR_FILE1(type, name, file, func, type1, arg1) \
+    static type (*real_ ## func)(type1, va_list); \
+    type name(type1 arg1, ...) { \
+        va_list ap; \
+        _HOOK_PRE_FILE(type, func, file) \
+        va_start(ap, arg1); \
+        result = real_ ## func(arg1, ap); \
+        va_end(ap); \
+        _HOOK_POST_FILE(file) \
+    }
+#define HOOK_VAR_FILE2(type, name, file, func, type1, arg1, type2, arg2) \
+    static type (*real_ ## func)(type1, type2, va_list); \
+    type name(type1 arg1, type2 arg2, ...) { \
+        va_list ap; \
+        _HOOK_PRE_FILE(type, func, file) \
+        va_start(ap, arg2); \
+        result = real_ ## func(arg1, arg2, ap); \
+        va_end(ap); \
+        _HOOK_POST_FILE(file) \
+    }
+#define HOOK_VAR_FILE3(type, name, file, func, type1, arg1, type2, arg2, type3, arg3) \
+    static type (*real_ ## func)(type1, type2, type3, va_list); \
+    type name(type1 arg1, type2 arg2, type3 arg3, ...) \
+    { \
+        va_list ap; \
+        _HOOK_PRE_FILE(type, func, file) \
+        va_start(ap, arg3); \
+        result = real_ ## func(arg1, arg2, arg3, ap); \
+        va_end(ap); \
+        _HOOK_POST_FILE(file) \
+    }
+
+#endif