argcheck: a module to check argument ranges

This code provides some macros to check arguments for valid value ranges.
Consider this a mild version of assert(3), because all it does is to log
a message and continue.

These macros don't replace error handling, but they are useful in
situations where an error is unexpected but not common, i.e.
this shouldn't happen but if it does let me know".

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

Makefile-ccan

@@ -8,6 +8,7 @@ CFLAGS = $(CCAN_CFLAGS) -I. $(DEPGEN)
 
 # Modules which are just a header:
 MODS_NO_SRC := alignof \
+	argcheck \
 	array_size \
 	asearch \
 	bitmap \

ccan/argcheck/LICENSE

@@ -0,0 +1 @@
+../../licenses/BSD-MIT

ccan/argcheck/_info

@@ -0,0 +1,73 @@
+#include "config.h"
+
+/**
+ * argcheck - macros to check arguments at runtime
+ *
+ * This code provides some macros to check arguments for valid value ranges.
+ * Consider this a mild version of assert(3), because all it does is to log
+ * a message and continue.
+ *
+ * These macros don't replace error handling, but they are useful in
+ * situations where an error is unexpected but not common, i.e.
+ * "this shouldn't happen but if it does let me know".
+ *
+ * argcheck's error messages can be disabled by defining
+ * ARGCHECK_DISABLE_LOGGING before including the header file. The conditions
+ * will continue to evaluate but no error messages will be generated. It is thus
+ * safe to use argcheck macros inside if conditions.
+ *
+ * By default, argcheck prints to fprintf(stderr). That can be changed by
+ * defining argcheck_log to a custom log function. See argcheck_log_() for the
+ * function signature. If ARGCHECK_DISABLE_LOGGING is defined, the custom log
+ * function is not called.
+ *
+ * Example:
+ *	#include <stdio.h>
+ *	#include <ccan/argcheck/argcheck.h>
+ *
+ *	enum state { S1, S2, S3 };
+ *
+ *	static int some_state_machine(enum state s) {
+ *	    int b;
+ *
+ *	    argcheck_int_range(s, S1, S3);
+ *
+ *	    switch(s) {
+ *		case S1: b = 8; break;
+ *		case S2: b = 9; break;
+ *		case S3: b = 88; break;
+ *	 	default:
+ *			break;
+ *	    }
+ *
+ *	    return b;
+ *      }
+ *
+ *	int main(int argc, char *argv[]) {
+ *	    int a = S1;
+ *
+ * 	    if (!argcheck_int_gt(argc, 1))
+ *		return 1;
+ *
+ *	    return some_state_machine(a);
+ *      }
+ *
+ * Author: Peter Hutterer <peter.hutterer@who-t.net>
+ * Maintainer: Peter Hutterer <peter.hutterer@who-t.net>
+ * License: BSD-MIT
+ */
+
+int main(int argc, char *argv[])
+{
+	/* Expect exactly one argument */
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/likely\n");
+		printf("ccan/compiler\n");
+		return 0;
+	}
+
+	return 1;
+}

ccan/argcheck/argcheck.h

@@ -0,0 +1,455 @@
+/*****************************************************************************
+ *
+ * argcheck - macros for argument value checking
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ ****************************************************************************/
+
+#ifndef CCAN_ARGCHECK_H
+#define CCAN_ARGCHECK_H
+#include <stdio.h>
+#include <string.h>
+#include <stdarg.h>
+
+#include <ccan/likely/likely.h>
+#include <ccan/compiler/compiler.h>
+
+/**
+ * ARGCHECK_DISABLE_LOGGING - define to disable any logging done by
+ * argcheck. This does not disable the actual checks, merely the invocation
+ * of the argcheck_log function, be it custom or the default logging
+ * function.
+ */
+#ifdef ARGCHECK_DISABLE_LOGGING
+#undef argcheck_log
+#define argcheck_log(...) /* __VA_ARGS__ */
+#else
+#ifndef argcheck_log
+/**
+ * argcheck_log - logging function for failed argcheck tests
+ *
+ * Override this function to hook up your own logging function. The function
+ * will be called once for each failed test.
+ */
+#define argcheck_log argcheck_log_
+#endif /* argcheck_log */
+
+static inline void COLD PRINTF_FMT(4, 5)
+argcheck_log_(const char *file, int line, const char *func,
+	      const char *msg, ...)
+{
+	va_list args;
+	va_start(args, msg);
+	fprintf(stderr, "argcheck: %s:%d %s\nargcheck: ", file, line, func);
+	vfprintf(stderr, msg, args);
+	va_end(args);
+}
+#endif
+
+/**
+ * argcheck_int_eq - check the argument is equal to the value.
+ */
+#define argcheck_int_eq(arg, val) \
+	argcheck_int_eq_(arg, val, #arg, #val, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_int_ne - check the argument is not equal to the value
+ */
+#define argcheck_int_ne(arg, val) \
+	argcheck_int_ne_(arg, val, #arg, #val, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_int_ge - check the argument is equal or greater than the value
+ */
+#define argcheck_int_ge(arg, val) \
+	argcheck_int_ge_(arg, val, #arg, #val, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_int_gt - check the argument is greater than the value
+ */
+#define argcheck_int_gt(arg, val) \
+	argcheck_int_gt_(arg, val, #arg, #val, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_int_le - check the argument is equal or less than the value
+ */
+#define argcheck_int_le(arg, val) \
+	argcheck_int_le_(arg, val, #arg, #val, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_int_lt - check the argument is less than the value
+ */
+#define argcheck_int_lt(arg, val) \
+	argcheck_int_lt_(arg, val, #arg, #val, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_int_range - check the argument is within a range (inclusive)
+ */
+#define argcheck_int_range(arg, min, max) \
+	argcheck_int_range_(arg, min, max, #arg, #min, #max, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_flag_set - check if a flag is set
+ */
+#define argcheck_flag_set(arg, flag) \
+	argcheck_flag_set_(arg, flag, #arg, #flag, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_flag_unset - check if a flag is not set
+ */
+#define argcheck_flag_unset(arg, flag) \
+	argcheck_flag_unset_(arg, flag, #arg, #flag, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_ptr_not_null - check that a pointer is not NULL
+ */
+#define argcheck_ptr_not_null(arg) \
+	argcheck_ptr_not_null_(arg, #arg, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_ptr_null - check that a pointer is NULL
+ */
+#define argcheck_ptr_null(arg) \
+	argcheck_ptr_null_(arg, #arg, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_null - see argcheck_ptr_null
+ */
+#define argcheck_str_null(arg) \
+	argcheck_str_null_(arg, #arg, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_not_null - see argcheck_ptr_not_null
+ */
+#define argcheck_str_not_null(arg) \
+	argcheck_str_not_null_(arg, #arg, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_zero - check that a string is not NULL and of zero length
+ */
+#define argcheck_str_zero_len(arg) \
+	argcheck_str_zero_len_(arg, #arg, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_null_or_zero - check that a string is either NULL or of zero length
+ */
+#define argcheck_str_null_or_zero_len(arg) \
+	argcheck_str_null_or_zero_len_(arg, #arg, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_not_zero - check that a string is not NULL and has a length greater than 0
+ */
+#define argcheck_str_not_zero_len(arg) \
+	argcheck_str_not_zero_len_(arg, #arg, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_null_or_not_zero - check that a string is either NULL or has a length greater than 0
+ */
+#define argcheck_str_null_or_not_zero_len(arg) \
+	argcheck_str_null_or_not_zero_len_(arg, #arg, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_min_len - check that a string is not NULL and has a length greater than or equal to a minimum
+ */
+#define argcheck_str_min_len(arg, min) \
+	argcheck_str_min_len_(arg, #arg, min, #min, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_max_len - check that a string is not NULL and has a length less than or equal to a maximum
+ */
+#define argcheck_str_max_len(arg, max) \
+	argcheck_str_max_len_(arg, #arg, max, #max, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_null_or_min_len - check that a string is NULL or has a length greater than or equal to a minimum
+ */
+#define argcheck_str_null_or_min_len(arg, min) \
+	argcheck_str_null_or_min_len_(arg, #arg, min, #min, __FILE__, __LINE__, __func__)
+/**
+ * argcheck_str_null_or_max_len - check that a string is NULL or has a length less than or equal to a maximum
+ */
+#define argcheck_str_null_or_max_len(arg, max) \
+	argcheck_str_null_or_max_len_(arg, #arg, max, #max, __FILE__, __LINE__, __func__)
+
+/*
+
+   below is the actual implemenation. do not use it directly, use the macros
+   above instead
+
+ */
+
+static inline int argcheck_int_eq_(int a, int b, const char *astr, const char *bstr,
+				   const char *file, int line, const char *func)
+{
+	if (likely(a == b))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "condition \"(%s == %s)\" (%d == %d) failed\n", astr, bstr, a, b);
+	return 0;
+}
+
+static inline int argcheck_int_ne_(int a, int b, const char *astr, const char *bstr,
+				   const char *file, int line, const char *func)
+{
+	if (likely(a != b))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "condition \"(%s != %s)\" (%d != %d) failed\n", astr, bstr, a, b);
+	return 0;
+}
+
+static inline int argcheck_int_ge_(int a, int b, const char *astr, const char *bstr,
+				   const char *file, int line, const char *func)
+{
+	if (likely(a >= b))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "condition \"(%s >= %s)\" (%d >= %d) failed\n", astr, bstr, a, b);
+	return 0;
+}
+
+static inline int argcheck_int_gt_(int a, int b, const char *astr, const char *bstr,
+				   const char *file, int line, const char *func)
+{
+	if (likely(a > b))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "condition \"(%s > %s)\" (%d > %d) failed\n", astr, bstr, a, b);
+	return 0;
+}
+
+static inline int argcheck_int_le_(int a, int b, const char *astr, const char *bstr,
+				   const char *file, int line, const char *func)
+{
+	if (likely(a <= b))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "condition \"(%s <= %s)\" (%d <= %d) failed\n", astr, bstr, a, b);
+	return 0;
+}
+
+static inline int argcheck_int_lt_(int a, int b, const char *astr, const char *bstr,
+				   const char *file, int line, const char *func)
+{
+	if (likely(a < b))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "condition \"(%s < %s)\" (%d < %d) failed\n", astr, bstr, a, b);
+	return 0;
+}
+
+static inline int argcheck_int_range_(int v, int min,  int max,
+				      const char *vstr,
+				      const char *minstr, const char *maxstr,
+				      const char *file, int line, const char *func)
+{
+	if (!argcheck_int_le_(min, max, minstr, maxstr, file, line, func))
+		return 0;
+
+	if (likely(v >= min && v <= max))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "condition \"(%s <= %s <= %s)\" (%d <= %d <= %d) failed\n",
+		     minstr, vstr, maxstr, min, v, max);
+	return 0;
+}
+
+static inline int argcheck_flag_set_(int arg, int flag,
+				     const char *argstr, const char *flagstr,
+				     const char *file, int line, const char *func)
+{
+	if (!argcheck_int_ne_(flag, 0, flagstr, "0", file, line, func))
+		return 0;
+
+	if (likely(arg & flag))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "flag \"%s\" (%d) is not set on \"%s\" (%d)\"\n",
+		     flagstr, flag, argstr, arg);
+	return 0;
+}
+
+static inline int argcheck_flag_unset_(int arg, int flag,
+				       const char *argstr, const char *flagstr,
+				       const char *file, int line, const char *func)
+{
+	if (!argcheck_int_ne_(flag, 0, flagstr, "0", file, line, func))
+		return 0;
+
+	if (likely((arg & flag) == 0))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "flag \"%s\" (%d) must not be set on \"%s\" (%d)\"\n",
+		     flagstr, flag, argstr, arg);
+	return 0;
+}
+
+static inline int argcheck_ptr_not_null_(const void *arg, const char *argstr,
+				        const char *file, int line, const char *func)
+{
+	if (likely(arg != NULL))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must not be NULL\n", argstr);
+	return 0;
+}
+
+static inline int argcheck_ptr_null_(const void *arg, const char *argstr,
+				     const char *file, int line, const char *func)
+{
+	if (likely(arg == NULL))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must be NULL\n", argstr);
+	return 0;
+}
+
+static inline int argcheck_str_null_(const char *arg, const char *argstr,
+				     const char *file, int line, const char *func)
+{
+	return argcheck_ptr_null_(arg, argstr, file, line, func);
+}
+
+static inline int argcheck_str_not_null_(const char *arg, const char *argstr,
+				         const char *file, int line, const char *func)
+{
+	return argcheck_ptr_not_null_(arg, argstr, file, line, func);
+}
+
+static inline int argcheck_str_zero_len_(const char *arg, const char *argstr,
+				         const char *file, int line, const char *func)
+{
+	if (!argcheck_str_not_null_(arg, argstr, file, line, func))
+		return 0;
+
+	if (likely(*arg == '\0'))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must be a zero-length string\n", argstr);
+	return 0;
+}
+
+
+static inline int argcheck_str_null_or_zero_len_(const char *arg, const char *argstr,
+						 const char *file, int line, const char *func)
+{
+	if (likely(arg == NULL || *arg == '\0'))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must be NULL or a zero-length string\n", argstr);
+	return 0;
+}
+
+static inline int argcheck_str_not_zero_len_(const char *arg, const char *argstr,
+					     const char *file, int line, const char *func)
+{
+	if (!argcheck_str_not_null_(arg, argstr, file, line, func))
+		return 0;
+
+	if (likely(*arg != '\0'))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must not be a zero-length string\n", argstr);
+	return 0;
+}
+
+static inline int argcheck_str_null_or_not_zero_len_(const char *arg, const char *argstr,
+						     const char *file, int line, const char *func)
+{
+	if (likely(arg == NULL || *arg != '\0'))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must be NULL or not a zero-length string\n", argstr);
+	return 0;
+}
+
+static inline int argcheck_str_min_len_(const char *arg, const char *argstr,
+					int min, const char *minstr,
+					const char *file, int line, const char *func)
+{
+	int len;
+
+	if (!argcheck_str_not_null_(arg, argstr, file, line, func))
+		return 0;
+
+	len = strlen(arg);
+	if (likely(len >= min))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must be at least \"%s\" (%d) long, is '%s' (length %d)\n", argstr,
+		     minstr, min, arg, len);
+	return 0;
+}
+
+static inline int argcheck_str_max_len_(const char *arg, const char *argstr,
+					int max, const char *maxstr,
+					const char *file, int line, const char *func)
+{
+	int len;
+
+	if (!argcheck_str_not_null_(arg, argstr, file, line, func))
+		return 0;
+
+	len = strlen(arg);
+	if (likely(len <= max))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must be at most \"%s\" (%d) long, is '%s' (length %d)\n", argstr,
+		     maxstr, max, arg, len);
+	return 0;
+}
+
+static inline int argcheck_str_null_or_min_len_(const char *arg, const char *argstr,
+						int min, const char *minstr,
+						const char *file, int line, const char *func)
+{
+	int len;
+
+	if (likely(arg == NULL))
+		return 1;
+
+	len = strlen(arg);
+	if (likely(len >= min))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must be NULL or at least \"%s\" (%d) long, is '%s' (length %d)\n", argstr,
+		     minstr, min, arg, len);
+	return 0;
+}
+
+static inline int argcheck_str_null_or_max_len_(const char *arg, const char *argstr,
+						int max, const char *maxstr,
+						const char *file, int line, const char *func)
+{
+	int len;
+
+	if (likely(arg == NULL))
+		return 1;
+
+	len = strlen(arg);
+	if (likely(len <= max))
+		return 1;
+
+	argcheck_log(file, line, func,
+		     "\"%s\" must be NULL or at most \"%s\" (%d) long, is '%s' (length %d)\n", argstr,
+		     maxstr, max, arg, len);
+	return 0;
+}
+
+#endif /* CCAN_ARGCHECK_H */

ccan/argcheck/test/run.c

@@ -0,0 +1,101 @@
+#include <ccan/tap/tap.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+#include <ccan/argcheck/argcheck.h>
+
+int main(void)
+{
+	int a = 0;
+	const int flag = 0x1;
+	const int invalid_flag = 0x0;
+	int *ptr = NULL,
+	    *ptr_not_null = &a;
+
+	const char *str = "hello",
+	           *str_zero = "\0",
+		   *str_null = NULL;
+
+	plan_tests(60);
+
+	ok1(!argcheck_int_eq(a, 1));
+	ok1(argcheck_int_eq(a, 0));
+
+	ok1(!argcheck_int_ne(a, 0));
+	ok1(argcheck_int_ne(a, 10));
+
+	ok1(!argcheck_int_ge(a, 1));
+	ok1(argcheck_int_ge(a, 0));
+	ok1(argcheck_int_ge(a, -1));
+
+	ok1(!argcheck_int_gt(a, 1));
+	ok1(!argcheck_int_gt(a, 0));
+	ok1(argcheck_int_gt(a, -1));
+
+	ok1(!argcheck_int_le(a, -1));
+	ok1(argcheck_int_le(a, 0));
+	ok1(argcheck_int_le(a, 1));
+
+	ok1(!argcheck_int_lt(a, -1));
+	ok1(!argcheck_int_lt(a, 0));
+	ok1(argcheck_int_lt(a, 1));
+
+	ok1(!argcheck_int_range(a, 0, -1));
+	ok1(!argcheck_int_range(a, -3, -1));
+	ok1(argcheck_int_range(a, 0, 1));
+	ok1(argcheck_int_range(a, -1, 0));
+
+	ok1(!argcheck_flag_set(a, invalid_flag));
+	ok1(!argcheck_flag_set(a, flag));
+	ok1(argcheck_flag_set(a | flag, flag));
+
+	ok1(!argcheck_flag_unset(a, invalid_flag));
+	ok1(!argcheck_flag_unset(a | flag, flag));
+	ok1(argcheck_flag_unset(a, flag));
+
+	ok1(argcheck_ptr_null(ptr));
+	ok1(!argcheck_ptr_not_null(ptr));
+	ok1(!argcheck_ptr_null(ptr_not_null));
+	ok1(argcheck_ptr_not_null(ptr_not_null));
+
+	ok1(argcheck_str_null(str_null));
+	ok1(!argcheck_str_not_null(str_null));
+	ok1(!argcheck_str_null(str));
+	ok1(argcheck_str_not_null(str));
+	ok1(!argcheck_str_null(str_zero));
+	ok1(argcheck_str_not_null(str_zero));
+
+	ok1(!argcheck_str_zero_len(str_null));
+	ok1(argcheck_str_zero_len(str_zero));
+	ok1(!argcheck_str_zero_len(str));
+
+	ok1(!argcheck_str_not_zero_len(str_null));
+	ok1(!argcheck_str_not_zero_len(str_zero));
+	ok1(argcheck_str_not_zero_len(str));
+
+	ok1(!argcheck_str_min_len(str_null, 1));
+	ok1(!argcheck_str_min_len(str_zero, 1));
+	ok1(argcheck_str_min_len(str, 1));
+
+	ok1(!argcheck_str_max_len(str_null, 1));
+	ok1(argcheck_str_max_len(str_zero, 1));
+	ok1(!argcheck_str_max_len(str, 1));
+
+	ok1(argcheck_str_null_or_zero_len(str_null));
+	ok1(argcheck_str_null_or_zero_len(str_zero));
+	ok1(!argcheck_str_null_or_zero_len(str));
+
+	ok1(argcheck_str_null_or_not_zero_len(str_null));
+	ok1(!argcheck_str_null_or_not_zero_len(str_zero));
+	ok1(argcheck_str_null_or_not_zero_len(str));
+
+	ok1(argcheck_str_null_or_min_len(str_null, 1));
+	ok1(!argcheck_str_null_or_min_len(str_zero, 1));
+	ok1(argcheck_str_null_or_min_len(str, 1));
+
+	ok1(argcheck_str_null_or_max_len(str_null, 1));
+	ok1(argcheck_str_null_or_max_len(str_zero, 1));
+	ok1(!argcheck_str_null_or_max_len(str, 1));
+
+	return exit_status();
+}