[test] Add setjmp()/longjmp() self-tests

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/tests/setjmp_test.c

@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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.
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+/** @file
+ *
+ * setjmp()/longjmp() tests
+ *
+ */
+
+/* Forcibly enable assertions */
+#undef NDEBUG
+
+#include <stddef.h>
+#include <assert.h>
+#include <setjmp.h>
+#include <ipxe/test.h>
+
+/** A setjmp()/longjmp() test */
+struct setjmp_test {
+	/** Jump buffer */
+	jmp_buf env;
+	/** Expected value */
+	int expected;
+	/** Test code file */
+	const char *file;
+	/** Test code line */
+	unsigned int line;
+};
+
+/** Expected jump */
+static struct setjmp_test *jumped;
+
+/**
+ * Report a setjmp() test result
+ *
+ * @v test		setjmp()/longjmp() test
+ *
+ * This has to be implemented as a macro since if it were a function
+ * then the context saved by setjmp() would be invalidated when the
+ * function returned.
+ */
+#define setjmp_ok( test ) do {						\
+	int value;							\
+	/* Sanity check */						\
+	assert ( jumped == NULL );					\
+	/* Initialise test */						\
+	(test)->expected = 0;						\
+	(test)->file = __FILE__;					\
+	(test)->line = __LINE__;					\
+	/* Perform setjmp() */						\
+	value = setjmp ( (test)->env );					\
+	/* Report setjmp()/longjmp() result */				\
+	setjmp_return_ok ( (test), value );				\
+	} while ( 0 )
+
+/**
+ * Report a setjmp()/longjmp() test result
+ *
+ * @v test		setjmp()/longjmp() test
+ * @v value		Value returned from setjmp()
+ *
+ * This function ends up reporting results from either setjmp() or
+ * longjmp() tests (since calls to longjmp() will return via the
+ * corresponding setjmp()).  It therefore uses the test code file and
+ * line stored in the test structure, which will represent the line
+ * from which either setjmp() or longjmp() was called.
+ */
+static void setjmp_return_ok ( struct setjmp_test *test, int value ) {
+
+	/* Determine whether this was reached via setjmp() or longjmp() */
+	if ( value == 0 ) {
+		/* This is the initial call to setjmp() */
+		okx ( test->expected == 0, test->file, test->line );
+		okx ( jumped == NULL, test->file, test->line );
+	} else {
+		/* This is reached via a call to longjmp() */
+		okx ( value == test->expected, test->file, test->line );
+		okx ( jumped == test, test->file, test->line );
+	}
+
+	/* Clear expected jump */
+	jumped = NULL;
+}
+
+/**
+ * Report a longjmp() test result
+ *
+ * @v test		setjmp()/longjmp() test
+ * @v file		Test code file
+ * @v line		Test code line
+ */
+static void longjmp_okx ( struct setjmp_test *test, int value,
+			  const char *file, unsigned int line ) {
+
+	/* Record expected value.  A zero passed to longjmp() should
+	 * result in setjmp() returning a value of one.
+	 */
+	test->expected = ( value ? value : 1 );
+
+	/* Record test code file and line */
+	test->file = file;
+	test->line = line;
+
+	/* Record expected jump */
+	jumped = test;
+
+	/* Perform longjmp().  Should return via setjmp_okx() */
+	longjmp ( test->env, value );
+
+	/* longjmp() should never return */
+	assert ( 0 );
+}
+#define longjmp_ok( test, value ) \
+	longjmp_okx ( test, value, __FILE__, __LINE__ )
+
+/**
+ * Perform setjmp()/longjmp() self-tests
+ *
+ */
+static void setjmp_test_exec ( void ) {
+	static struct setjmp_test alpha;
+	static struct setjmp_test beta;
+	static int iteration;
+
+	/* This is one of the very few situations in which the
+	 * "for-case" pattern is justified.
+	 */
+	for ( iteration = 0 ; iteration < 10 ; iteration++ ) {
+		DBGC ( jumped, "SETJMP test iteration %d\n", iteration );
+		switch ( iteration ) {
+		case 0: setjmp_ok ( &alpha ); break;
+		case 1: setjmp_ok ( &beta ); break;
+		case 2:	longjmp_ok ( &alpha, 0 );
+		case 3: longjmp_ok ( &alpha, 1 );
+		case 4: longjmp_ok ( &alpha, 2 );
+		case 5: longjmp_ok ( &beta, 17 );
+		case 6: longjmp_ok ( &beta, 29 );
+		case 7: longjmp_ok ( &alpha, -1 );
+		case 8: longjmp_ok ( &beta, 0 );
+		case 9: longjmp_ok ( &beta, 42 );
+		}
+	}
+}
+
+/** setjmp()/longjmp() self-test */
+struct self_test setjmp_test __self_test = {
+	.name = "setjmp",
+	.exec = setjmp_test_exec,
+};

src/tests/tests.c

@@ -63,3 +63,4 @@ REQUIRE_OBJECT ( png_test );
 REQUIRE_OBJECT ( dns_test );
 REQUIRE_OBJECT ( uri_test );
 REQUIRE_OBJECT ( profile_test );
+REQUIRE_OBJECT ( setjmp_test );