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, 507 insertions, 0 deletions

diff --git a/src/libstrongswan/utils/printf_hook/printf_hook_vstr.c b/src/libstrongswan/utils/printf_hook/printf_hook_vstr.c
new file mode 100644
index 000000000..f1884f119
--- /dev/null
+++ b/src/libstrongswan/utils/printf_hook/printf_hook_vstr.c
@@ -0,0 +1,507 @@
+/*
+ * Copyright (C) 2009-2013 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.
+ */
+
+#include "printf_hook.h"
+
+#include <utils/utils.h>
+#include <utils/debug.h>
+#include <threading/thread_value.h>
+
+#include <vstr.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+typedef struct private_printf_hook_t private_printf_hook_t;
+typedef struct printf_hook_handler_t printf_hook_handler_t;
+
+#define PRINTF_BUF_LEN 8192
+#define ARGS_MAX 3
+
+/**
+ * private data of printf_hook
+ */
+struct private_printf_hook_t {
+
+	/**
+	 * public functions
+	 */
+	printf_hook_t public;
+};
+
+/**
+ * struct with information about a registered handler
+ */
+struct printf_hook_handler_t {
+
+	/**
+	 * callback function
+	 */
+	printf_hook_function_t hook;
+
+	/**
+	 * number of arguments
+	 */
+	int numargs;
+
+	/**
+	 * types of the arguments, VSTR_TYPE_FMT_*
+	 */
+	int argtypes[ARGS_MAX];
+
+	/**
+	 * name required for Vstr
+	 */
+	char *name;
+};
+
+/**
+ * Data to pass to a printf hook.
+ */
+struct printf_hook_data_t {
+
+	/**
+	 * Base to append printf to
+	 */
+	Vstr_base *base;
+
+	/**
+	 * Position in base to write to
+	 */
+	size_t pos;
+};
+
+/* A-Z | 6 other chars | a-z */
+static printf_hook_handler_t *printf_hooks[58];
+
+#define SPEC_TO_INDEX(spec) ((int)(spec) - (int)'A')
+
+/**
+ * These are used below, whenever the public wrapper functions are called before
+ * initialization or after destruction.
+ */
+#undef vprintf
+#undef vfprintf
+#undef vsnprintf
+
+/**
+ * Vstr variant of print_in_hook()
+ */
+size_t print_in_hook(printf_hook_data_t *data, char *fmt, ...)
+{
+	size_t written;
+	va_list args;
+
+	va_start(args, fmt);
+	written = vstr_add_vfmt(data->base, data->pos, fmt, args);
+	va_end(args);
+
+	data->pos += written;
+	return written;
+}
+
+/**
+ * Vstr custom format specifier callback function.
+ */
+static int custom_fmt_cb(Vstr_base *base, size_t pos, Vstr_fmt_spec *fmt_spec)
+{
+	int i;
+	const void *args[ARGS_MAX];
+	printf_hook_spec_t spec;
+	printf_hook_handler_t *handler;
+	printf_hook_data_t data = {
+		.base = base,
+		.pos = pos,
+	};
+
+	handler = printf_hooks[SPEC_TO_INDEX(fmt_spec->name[0])];
+	for (i = 0; i < handler->numargs; i++)
+	{
+		switch (handler->argtypes[i])
+		{
+			case VSTR_TYPE_FMT_INT:
+				args[i] = VSTR_FMT_CB_ARG_PTR(fmt_spec, i);
+				break;
+			case VSTR_TYPE_FMT_PTR_VOID:
+				args[i] = &VSTR_FMT_CB_ARG_PTR(fmt_spec, i);
+				break;
+		}
+	}
+
+	spec.hash = fmt_spec->fmt_hash;
+	spec.plus = fmt_spec->fmt_plus;
+	spec.minus = fmt_spec->fmt_minus;
+	spec.width = fmt_spec->fmt_field_width;
+
+	handler->hook(&data, &spec, args);
+
+	return 1;
+}
+
+/**
+ * Add a custom format handler to the given Vstr_conf object
+ */
+static void vstr_fmt_add_handler(Vstr_conf *conf, printf_hook_handler_t *handler)
+{
+	int *at;
+
+	at = handler->argtypes;
+	switch (handler->numargs)
+	{
+		case 1:
+			vstr_fmt_add(conf, handler->name, custom_fmt_cb, at[0],
+						 VSTR_TYPE_FMT_END);
+			break;
+		case 2:
+			vstr_fmt_add(conf, handler->name, custom_fmt_cb, at[0],
+						 at[1], VSTR_TYPE_FMT_END);
+			break;
+		case 3:
+			vstr_fmt_add(conf, handler->name, custom_fmt_cb, at[0],
+						 at[1], at[2], VSTR_TYPE_FMT_END);
+			break;
+	}
+}
+
+/**
+ * Thread specific vstr config
+ */
+static thread_value_t *vstr_conf = NULL;
+
+/**
+ * Create vstr config for current thread
+ */
+static Vstr_conf *create_vstr_conf()
+{
+	Vstr_conf *conf;
+	int i;
+
+	conf = vstr_make_conf();
+	vstr_cntl_conf(conf, VSTR_CNTL_CONF_SET_FMT_CHAR_ESC, '%');
+	vstr_cntl_conf(conf, VSTR_CNTL_CONF_SET_TYPE_GRPALLOC_CACHE,
+						 VSTR_TYPE_CNTL_CONF_GRPALLOC_CSTR);
+	vstr_cntl_conf(conf, VSTR_CNTL_CONF_SET_NUM_BUF_SZ, PRINTF_BUF_LEN);
+
+	for (i = 0; i < countof(printf_hooks); i++)
+	{
+		if (printf_hooks[i])
+		{
+			vstr_fmt_add_handler(conf, printf_hooks[i]);
+		}
+	}
+	return conf;
+}
+
+/**
+ * Get vstr config of current thread
+ */
+static inline Vstr_conf *get_vstr_conf()
+{
+	Vstr_conf *conf = NULL;
+
+	if (vstr_conf)
+	{
+		conf = (Vstr_conf*)vstr_conf->get(vstr_conf);
+		if (!conf)
+		{
+			conf = create_vstr_conf();
+			vstr_conf->set(vstr_conf, conf);
+		}
+	}
+	return conf;
+}
+
+/**
+ * Wrapper functions for printf and alike
+ */
+int vstr_wrapper_printf(const char *format, ...)
+{
+	int written;
+	va_list args;
+	va_start(args, format);
+	written = vstr_wrapper_vprintf(format, args);
+	va_end(args);
+	return written;
+}
+
+int vstr_wrapper_fprintf(FILE *stream, const char *format, ...)
+{
+	int written;
+	va_list args;
+	va_start(args, format);
+	written = vstr_wrapper_vfprintf(stream, format, args);
+	va_end(args);
+	return written;
+}
+
+int vstr_wrapper_sprintf(char *str, const char *format, ...)
+{
+	int written;
+	va_list args;
+	va_start(args, format);
+	written = vstr_wrapper_vsprintf(str, format, args);
+	va_end(args);
+	return written;
+}
+
+int vstr_wrapper_snprintf(char *str, size_t size, const char *format, ...)
+{
+	int written;
+	va_list args;
+	va_start(args, format);
+	written = vstr_wrapper_vsnprintf(str, size, format, args);
+	va_end(args);
+	return written;
+}
+
+int vstr_wrapper_asprintf(char **str, const char *format, ...)
+{
+	int written;
+	va_list args;
+	va_start(args, format);
+	written = vstr_wrapper_vasprintf(str, format, args);
+	va_end(args);
+	return written;
+}
+
+static inline int vstr_wrapper_vprintf_internal(Vstr_conf *conf, FILE *stream,
+												const char *format,
+												va_list args)
+{
+	struct iovec *iov;
+	int iovcnt, written = 0;
+	Vstr_base *s;
+
+	s = vstr_make_base(conf);
+	vstr_add_vfmt(s, 0, format, args);
+	if (vstr_export_iovec_ptr_all(s, &iov, &iovcnt))
+	{
+		while (iovcnt--)
+		{
+			if (iov->iov_base)
+			{
+				written += fwrite(iov->iov_base, 1, iov->iov_len, stream);
+			}
+			iov++;
+		}
+	}
+	vstr_free_base(s);
+	return written;
+}
+
+int vstr_wrapper_vprintf(const char *format, va_list args)
+{
+	Vstr_conf *conf;
+
+	conf = get_vstr_conf();
+	if (conf)
+	{
+		return vstr_wrapper_vprintf_internal(conf, stdout, format, args);
+	}
+	return vprintf(format, args);
+}
+
+int vstr_wrapper_vfprintf(FILE *stream, const char *format, va_list args)
+{
+	Vstr_conf *conf;
+
+	conf = get_vstr_conf();
+	if (conf)
+	{
+		return vstr_wrapper_vprintf_internal(conf, stream, format, args);
+	}
+	return vfprintf(stream, format, args);
+}
+
+static inline int vstr_wrapper_vsnprintf_internal(char *str, size_t size,
+												  const char *format,
+												  va_list args)
+{
+	Vstr_conf *conf;
+	Vstr_base *s;
+	int written;
+
+	conf = get_vstr_conf();
+	if (conf)
+	{
+		s = vstr_make_base(conf);
+		vstr_add_vfmt(s, 0, format, args);
+		written = s->len;
+		vstr_export_cstr_buf(s, 1, s->len, str, (size > 0) ? size : s->len + 1);
+		vstr_free_base(s);
+		return written;
+	}
+	return vsnprintf(str, size, format, args);
+}
+
+int vstr_wrapper_vsprintf(char *str, const char *format, va_list args)
+{
+	return vstr_wrapper_vsnprintf_internal(str, 0, format, args);
+}
+
+int vstr_wrapper_vsnprintf(char *str, size_t size, const char *format,
+						   va_list args)
+{
+	if (size > 0)
+	{
+		return vstr_wrapper_vsnprintf_internal(str, size, format, args);
+	}
+	return 0;
+}
+
+int vstr_wrapper_vasprintf(char **str, const char *format, va_list args)
+{
+	size_t len = 100;
+	int written;
+
+	*str = malloc(len);
+	while (TRUE)
+	{
+		va_list ac;
+		va_copy(ac, args);
+		written = vstr_wrapper_vsnprintf_internal(*str, len, format, ac);
+		va_end(ac);
+		if (written < len)
+		{
+			break;
+		}
+		len = written + 1;
+		*str = realloc(*str, len);
+	}
+	return written;
+}
+
+METHOD(printf_hook_t, add_handler, void,
+	private_printf_hook_t *this, char spec, printf_hook_function_t hook, ...)
+{
+	int i = -1;
+	bool failed = FALSE;
+	printf_hook_handler_t *handler;
+	printf_hook_argtype_t argtype;
+	va_list args;
+
+	if (SPEC_TO_INDEX(spec) <= -1 ||
+		SPEC_TO_INDEX(spec) >= countof(printf_hooks))
+	{
+		DBG1(DBG_LIB, "'%c' is not a valid printf hook specifier, "
+			 "not registered!", spec);
+		return;
+	}
+
+	INIT(handler,
+		.hook = hook,
+	);
+
+	va_start(args, hook);
+	while (!failed)
+	{
+		argtype = va_arg(args, printf_hook_argtype_t);
+		if (argtype == PRINTF_HOOK_ARGTYPE_END)
+		{
+			break;
+		}
+		if (++i >= ARGS_MAX)
+		{
+			DBG1(DBG_LIB, "Too many arguments for printf hook with "
+				 "specifier '%c', not registered!", spec);
+			failed = TRUE;
+			break;
+		}
+		switch (argtype)
+		{
+			case PRINTF_HOOK_ARGTYPE_INT:
+				handler->argtypes[i] = VSTR_TYPE_FMT_INT;
+				break;
+			case PRINTF_HOOK_ARGTYPE_POINTER:
+				handler->argtypes[i] = VSTR_TYPE_FMT_PTR_VOID;
+				break;
+			default:
+				DBG1(DBG_LIB, "Invalid printf hook arg type for '%c'", spec);
+				failed = TRUE;
+				break;
+		}
+	}
+	va_end(args);
+
+	handler->numargs = i + 1;
+
+	if (!failed && handler->numargs > 0)
+	{
+		Vstr_conf *conf = get_vstr_conf();
+		handler->name = malloc(2);
+		handler->name[0] = spec;
+		handler->name[1] = '\0';
+		vstr_fmt_add_handler(conf, handler);
+		printf_hooks[SPEC_TO_INDEX(spec)] = handler;
+	}
+	else
+	{
+		free(handler);
+	}
+}
+
+METHOD(printf_hook_t, destroy, void,
+	private_printf_hook_t *this)
+{
+	int i;
+	Vstr_conf *conf;
+	printf_hook_handler_t *handler;
+
+	conf = get_vstr_conf();
+	for (i = 0; i < countof(printf_hooks); ++i)
+	{
+		handler = printf_hooks[i];
+		if (handler)
+		{
+			vstr_fmt_del(conf, handler->name);
+			free(handler->name);
+			free(handler);
+		}
+	}
+
+	/* freeing the Vstr_conf of the main thread */
+	vstr_conf->destroy(vstr_conf);
+	vstr_conf = NULL;
+	vstr_exit();
+	free(this);
+}
+
+/*
+ * see header file
+ */
+printf_hook_t *printf_hook_create()
+{
+	private_printf_hook_t *this;
+
+	INIT(this,
+		.public = {
+			.add_handler = _add_handler,
+			.destroy = _destroy,
+		},
+	);
+
+	memset(printf_hooks, 0, sizeof(printf_hooks));
+
+	if (!vstr_init())
+	{
+		DBG1(DBG_LIB, "failed to initialize Vstr library!");
+		free(this);
+		return NULL;
+	}
+	vstr_conf = thread_value_create((thread_cleanup_t)vstr_free_conf);
+
+	return &this->public;
+}