util: Add tests for the string buffer

More tests could probably be added, but this should cover
concatenation, resizing, clearing, formatted printing,
and checking the length, so it should be quite complete.

Signed-off-by: Thomas Helland <thomashelland90@gmail.com>
Reviewed-by: Nicolai Hähnle <nicolai.haehnle at amd.com>
Tested-by: Dieter Nützel <Dieter at nuetzel-hh.de>

V2: Address review feedback from Timothy, plus fixes
   - Use a large enough char array
   - Actually test the formatted appending
   - Test that clear function resets string length

V3: Port to gtest

V4: Fix test makefile
    Fix copyright header
    Fix missing extern C
    Use more appropriate name for C-file
    Add tests for append_char

configure.ac

@@ -2942,6 +2942,7 @@ AC_CONFIG_FILES([Makefile
                  src/mesa/state_tracker/tests/Makefile
                  src/util/Makefile
                  src/util/tests/hash_table/Makefile
+                 src/util/tests/string_buffer/Makefile
                  src/util/xmlpool/Makefile
                  src/vulkan/Makefile])
 

src/util/Makefile.am

@@ -19,7 +19,10 @@
 # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 # IN THE SOFTWARE.
 
-SUBDIRS = xmlpool . tests/hash_table
+SUBDIRS = . \
+	xmlpool \
+	tests/hash_table \
+	tests/string_buffer
 
 include Makefile.sources
 

src/util/tests/string_buffer/Makefile.am

@@ -0,0 +1,40 @@
+# Copyright © 2017 Thomas Helland
+#
+#  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 (including the next
+#  paragraph) 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.
+
+AM_CPPFLAGS = \
+	-I$(top_srcdir)/src \
+	-I$(top_srcdir)/include \
+	-I$(top_srcdir)/src/gtest/include \
+	$(PTHREAD_CFLAGS) \
+	$(DEFINES)
+
+TESTS = string_buffer_test
+
+check_PROGRAMS = $(TESTS)
+
+string_buffer_test_SOURCES = \
+	string_buffer_test.cpp
+
+string_buffer_test_LDADD = \
+	$(top_builddir)/src/gtest/libgtest.la \
+	$(top_builddir)/src/util/libmesautil.la \
+	$(PTHREAD_LIBS) \
+	$(DLOPEN_LIBS)

src/util/tests/string_buffer/string_buffer_test.cpp

@@ -0,0 +1,119 @@
+/*
+ * Copyright © 2017 Thomas Helland
+ *
+ * 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 (including the next
+ * paragraph) 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.
+ *
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <gtest/gtest.h>
+#include "util/string_buffer.h"
+
+/**
+ * \file string_buffer_test.cpp
+ *
+ * Test the string buffer implementation
+ */
+
+#define INITIAL_BUF_SIZE 6
+class string_buffer : public ::testing::Test {
+public:
+
+   struct _mesa_string_buffer *buf;
+   const char *str1 = "test1";
+   const char *str2 = "test2";
+   const char *str3 = "test1test2";
+   char str4[80];
+   char str5[40];
+
+   virtual void SetUp();
+   virtual void TearDown();
+};
+
+void
+string_buffer::SetUp()
+{
+   buf = _mesa_string_buffer_create(NULL, INITIAL_BUF_SIZE);
+}
+
+void
+string_buffer::TearDown()
+{
+   /* Finally, clean up after us */
+   _mesa_string_buffer_destroy(buf);
+}
+
+static uint32_t
+space_left_in_buffer(_mesa_string_buffer *buf)
+{
+   return buf->capacity - buf->length - 1;
+}
+
+TEST_F(string_buffer, string_buffer_tests)
+{
+   /* The string terminator needs one byte, so there should one "missing" */
+   EXPECT_TRUE(space_left_in_buffer(buf) == INITIAL_BUF_SIZE - 1);
+
+   /* Start by appending str1 */
+   EXPECT_TRUE(_mesa_string_buffer_append(buf, str1));
+   EXPECT_TRUE(space_left_in_buffer(buf) ==
+               INITIAL_BUF_SIZE - strlen(str1) - 1);
+   EXPECT_TRUE(strcmp(buf->buf, str1) == 0);
+
+   /* Add more, so that the string is resized */
+   EXPECT_TRUE(_mesa_string_buffer_append(buf, str2));
+
+   /* The string should now be equal to str3 */
+   EXPECT_TRUE(strcmp(buf->buf, str3) == 0);
+
+   /* Check that the length of the string is reset when clearing */
+   _mesa_string_buffer_clear(buf);
+   EXPECT_TRUE(buf->length == 0);
+   EXPECT_TRUE(strlen(buf->buf) == 0);
+
+   /* Test a string with some formatting */
+   sprintf(str4, "Testing formatting %d, %f", 100, 1.0);
+   EXPECT_TRUE(_mesa_string_buffer_printf(buf, "Testing formatting %d, %f", 100, 1.0));
+   EXPECT_TRUE(strcmp(buf->buf, str4) == 0);
+
+   /* Compile a string with some other formatting */
+   sprintf(str5, "Testing formatting %d, %x", 100, 0xDEADBEAF);
+
+   /* Concatenate str5 to str4 */
+   strcat(str4, str5);
+
+   /* Now use the formatted append function again */
+   EXPECT_TRUE(_mesa_string_buffer_printf(buf, "Testing formatting %d, %x", 100, 0xDEADBEAF));
+
+   /* The string buffer should now be equal to str4 */
+   EXPECT_TRUE(strcmp(buf->buf, str4) == 0);
+
+   _mesa_string_buffer_clear(buf);
+
+   /* Test appending by one char at a time */
+   EXPECT_TRUE(_mesa_string_buffer_append_char(buf, 'a'));
+   EXPECT_TRUE(buf->length == 1);
+   EXPECT_TRUE(strcmp(buf->buf, "a") == 0);
+   EXPECT_TRUE(_mesa_string_buffer_append_char(buf, 'a'));
+   EXPECT_TRUE(strcmp(buf->buf, "aa") == 0);
+}