[Qemu-devel] [PATCH v5 2/2] Tests: QEMUSizedBuffer/QEMUBuffer

["Dr. David Alan Gilbert (git)" <dgilbert@redhat.com>]

From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>

Modify some of tests/test-vmstate.c to use the in memory file based
on QEMUSizedBuffer to provide basic testing of QEMUSizedBuffer and
the associated memory backed QEMUFile type.

Only some of the tests are changed so that the fd backed QEMUFile is
still tested.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 tests/Makefile       |  2 +-
 tests/test-vmstate.c | 74 +++++++++++++++++++++++++++-------------------------
 2 files changed, 39 insertions(+), 37 deletions(-)

diff --git a/tests/Makefile b/tests/Makefile
index f5de29c..0ad7ac5 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -259,7 +259,7 @@ tests/test-qdev-global-props$(EXESUF): tests/test-qdev-global-props.o \
 	libqemuutil.a libqemustub.a
 tests/test-vmstate$(EXESUF): tests/test-vmstate.o \
 	vmstate.o qemu-file.o \
-	libqemuutil.a
+	libqemuutil.a libqemustub.a
 
 tests/test-qapi-types.c tests/test-qapi-types.h :\
 $(SRC_PATH)/tests/qapi-schema/qapi-schema-test.json $(SRC_PATH)/scripts/qapi-types.py
diff --git a/tests/test-vmstate.c b/tests/test-vmstate.c
index d72c64c..5e0fd13 100644
--- a/tests/test-vmstate.c
+++ b/tests/test-vmstate.c
@@ -43,6 +43,12 @@ void yield_until_fd_readable(int fd)
     select(fd + 1, &fds, NULL, NULL, NULL);
 }
 
+/*
+ * Some tests use 'open_test_file' to work on a real fd, some use
+ * an in memory file (QEMUSizedBuffer+qemu_bufopen); we could pick one
+ * but this way we test both.
+ */
+
 /* Duplicate temp_fd and seek to the beginning of the file */
 static QEMUFile *open_test_file(bool write)
 {
@@ -54,6 +60,30 @@ static QEMUFile *open_test_file(bool write)
     return qemu_fdopen(fd, write ? "wb" : "rb");
 }
 
+/* Open a read-only qemu-file from an existing memory block */
+static QEMUFile *open_mem_file_read(const void *data, size_t len)
+{
+    /* The qsb gets freed by qemu_fclose */
+    QEMUSizedBuffer *qsb = qsb_create(data, len);
+    g_assert(qsb);
+
+    return qemu_bufopen("r", qsb);
+}
+
+/*
+ * Check that the contents of the memory-buffered file f match
+ * the given size/data.
+ */
+static void check_mem_file(QEMUFile *f, void *data, size_t size)
+{
+    uint8_t *result = g_malloc(size);
+    const QEMUSizedBuffer *qsb = qemu_buf_get(f);
+    g_assert_cmpint(qsb_get_length(qsb), ==, size);
+    g_assert_cmpint(qsb_get_buffer(qsb, 0, size, result), ==, size);
+    g_assert_cmpint(memcmp(result, data, size), ==, 0);
+    g_free(result);
+}
+
 #define SUCCESS(val) \
     g_assert_cmpint((val), ==, 0)
 
@@ -371,14 +401,12 @@ static const VMStateDescription vmstate_skipping = {
 
 static void test_save_noskip(void)
 {
-    QEMUFile *fsave = open_test_file(true);
+    QEMUFile *fsave = qemu_bufopen("w", NULL);
     TestStruct obj = { .a = 1, .b = 2, .c = 3, .d = 4, .e = 5, .f = 6,
                        .skip_c_e = false };
     vmstate_save_state(fsave, &vmstate_skipping, &obj);
     g_assert(!qemu_file_get_error(fsave));
-    qemu_fclose(fsave);
 
-    QEMUFile *loading = open_test_file(false);
     uint8_t expected[] = {
         0, 0, 0, 1,             /* a */
         0, 0, 0, 2,             /* b */
@@ -387,52 +415,31 @@ static void test_save_noskip(void)
         0, 0, 0, 5,             /* e */
         0, 0, 0, 0, 0, 0, 0, 6, /* f */
     };
-    uint8_t result[sizeof(expected)];
-    g_assert_cmpint(qemu_get_buffer(loading, result, sizeof(result)), ==,
-                    sizeof(result));
-    g_assert(!qemu_file_get_error(loading));
-    g_assert_cmpint(memcmp(result, expected, sizeof(result)), ==, 0);
-
-    /* Must reach EOF */
-    qemu_get_byte(loading);
-    g_assert_cmpint(qemu_file_get_error(loading), ==, -EIO);
-
-    qemu_fclose(loading);
+    check_mem_file(fsave, expected, sizeof(expected));
+    qemu_fclose(fsave);
 }
 
 static void test_save_skip(void)
 {
-    QEMUFile *fsave = open_test_file(true);
+    QEMUFile *fsave = qemu_bufopen("w", NULL);
     TestStruct obj = { .a = 1, .b = 2, .c = 3, .d = 4, .e = 5, .f = 6,
                        .skip_c_e = true };
     vmstate_save_state(fsave, &vmstate_skipping, &obj);
     g_assert(!qemu_file_get_error(fsave));
-    qemu_fclose(fsave);
 
-    QEMUFile *loading = open_test_file(false);
     uint8_t expected[] = {
         0, 0, 0, 1,             /* a */
         0, 0, 0, 2,             /* b */
         0, 0, 0, 0, 0, 0, 0, 4, /* d */
         0, 0, 0, 0, 0, 0, 0, 6, /* f */
     };
-    uint8_t result[sizeof(expected)];
-    g_assert_cmpint(qemu_get_buffer(loading, result, sizeof(result)), ==,
-                    sizeof(result));
-    g_assert(!qemu_file_get_error(loading));
-    g_assert_cmpint(memcmp(result, expected, sizeof(result)), ==, 0);
-
-
-    /* Must reach EOF */
-    qemu_get_byte(loading);
-    g_assert_cmpint(qemu_file_get_error(loading), ==, -EIO);
+    check_mem_file(fsave, expected, sizeof(expected));
 
-    qemu_fclose(loading);
+    qemu_fclose(fsave);
 }
 
 static void test_load_noskip(void)
 {
-    QEMUFile *fsave = open_test_file(true);
     uint8_t buf[] = {
         0, 0, 0, 10,             /* a */
         0, 0, 0, 20,             /* b */
@@ -442,10 +449,8 @@ static void test_load_noskip(void)
         0, 0, 0, 0, 0, 0, 0, 60, /* f */
         QEMU_VM_EOF, /* just to ensure we won't get EOF reported prematurely */
     };
-    qemu_put_buffer(fsave, buf, sizeof(buf));
-    qemu_fclose(fsave);
 
-    QEMUFile *loading = open_test_file(false);
+    QEMUFile *loading = open_mem_file_read(buf, sizeof(buf));
     TestStruct obj = { .skip_c_e = false };
     vmstate_load_state(loading, &vmstate_skipping, &obj, 2);
     g_assert(!qemu_file_get_error(loading));
@@ -460,7 +465,6 @@ static void test_load_noskip(void)
 
 static void test_load_skip(void)
 {
-    QEMUFile *fsave = open_test_file(true);
     uint8_t buf[] = {
         0, 0, 0, 10,             /* a */
         0, 0, 0, 20,             /* b */
@@ -468,10 +472,8 @@ static void test_load_skip(void)
         0, 0, 0, 0, 0, 0, 0, 60, /* f */
         QEMU_VM_EOF, /* just to ensure we won't get EOF reported prematurely */
     };
-    qemu_put_buffer(fsave, buf, sizeof(buf));
-    qemu_fclose(fsave);
 
-    QEMUFile *loading = open_test_file(false);
+    QEMUFile *loading = open_mem_file_read(buf, sizeof(buf));
     TestStruct obj = { .skip_c_e = true, .c = 300, .e = 500 };
     vmstate_load_state(loading, &vmstate_skipping, &obj, 2);
     g_assert(!qemu_file_get_error(loading));
-- 
1.9.3