Merge branch 'printf-hook'

Adds a custom printf hook implementation as a fallback if neither the glibc
style hooks nor vstr is available. This can avoid the Vstr dependency on some
systems at the cost of slower and less complete printf functions.

1 files changed, 121 insertions, 0 deletions

diff --git a/src/libstrongswan/utils/printf_hook/printf_hook.h b/src/libstrongswan/utils/printf_hook/printf_hook.h
new file mode 100644
index 000000000..c1d6fa90d
--- /dev/null
+++ b/src/libstrongswan/utils/printf_hook/printf_hook.h
@@ -0,0 +1,121 @@
+/*
+ * Copyright (C) 2009 Tobias Brunner
+ * Copyright (C) 2006-2008 Martin Willi
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup printf_hook printf_hook
+ * @{ @ingroup utils
+ */
+
+#ifndef PRINTF_HOOK_H_
+#define PRINTF_HOOK_H_
+
+#include <stdlib.h>
+
+typedef struct printf_hook_t printf_hook_t;
+typedef struct printf_hook_spec_t printf_hook_spec_t;
+typedef struct printf_hook_data_t printf_hook_data_t;
+typedef enum printf_hook_argtype_t printf_hook_argtype_t;
+
+#if defined(USE_VSTR)
+# include "printf_hook_vstr.h"
+#elif defined(USE_BUILTIN_PRINTF)
+# include "printf_hook_builtin.h"
+#endif
+
+/**
+ * Argument types to pass to printf hook.
+ */
+enum printf_hook_argtype_t {
+	PRINTF_HOOK_ARGTYPE_END,
+	PRINTF_HOOK_ARGTYPE_INT,
+	PRINTF_HOOK_ARGTYPE_POINTER,
+};
+
+/**
+ * Callback function type for printf hooks.
+ *
+ * @param data		hook data, to pass to print_in_hook()
+ * @param spec		format specifier
+ * @param args		arguments array
+ * @return			number of characters written
+ */
+typedef int (*printf_hook_function_t)(printf_hook_data_t *data,
+									  printf_hook_spec_t *spec,
+									  const void *const *args);
+
+/**
+ * Properties of the format specifier
+ */
+struct printf_hook_spec_t {
+
+	/**
+	 * TRUE if a '#' was used in the format specifier
+	 */
+	int hash;
+
+	/**
+	 * TRUE if a '-' was used in the format specifier
+	 */
+	int minus;
+
+	/**
+	 * TRUE if a '+' was used in the format specifier
+	 */
+	int plus;
+
+	/**
+	 * The width as given in the format specifier.
+	 */
+	int width;
+};
+
+/**
+ * Printf handler management.
+ */
+struct printf_hook_t {
+
+	/**
+	 * Register a printf handler.
+	 *
+	 * @param spec		printf hook format character
+	 * @param hook		hook function
+	 * @param ...		list of PRINTF_HOOK_ARGTYPE_*, MUST end with PRINTF_HOOK_ARGTYPE_END
+	 */
+	void (*add_handler)(printf_hook_t *this, char spec,
+						printf_hook_function_t hook, ...);
+
+	/**
+	 * Destroy a printf_hook instance.
+	 */
+	void (*destroy)(printf_hook_t *this);
+};
+
+/**
+ * Create a printf_hook instance.
+ */
+printf_hook_t *printf_hook_create();
+
+/**
+ * Print with format string within a printf hook.
+ *
+ * @param data		hook data, as passed to printf hook
+ * @param fmt		printf format string
+ * @param ...		arguments to format string
+ * @return			number of characters written
+ */
+size_t print_in_hook(printf_hook_data_t *data, char *fmt, ...);
+
+#endif /** PRINTF_HOOK_H_ @}*/