[Qemu-devel] [PATCH v3 11/23] tests: Clean up string interpolation into QMP input (simple cases)

[Markus Armbruster <armbru@redhat.com>]

When you build QMP input manually like this

    cmd = g_strdup_printf("{ 'execute': 'migrate',"
                          "'arguments': { 'uri': '%s' } }",
                          uri);
    rsp = qmp(cmd);
    g_free(cmd);

you're responsible for escaping the interpolated values for JSON.  Not
done here, and therefore works only for sufficiently nice @uri.  For
instance, if @uri contained a single "'", qobject_from_vjsonf_nofail()
would abort.  A sufficiently nasty @uri could even inject unwanted
members into the arguments object.

Leaving interpolation into JSON to qmp() is more robust:

    rsp = qmp("{ 'execute': 'migrate', 'arguments': { 'uri': %s } }", uri);

It's also more concise.

Clean up the simple cases where we interpolate exactly a JSON value.

Bonus: gets rid of non-literal format strings.  A step towards
compile-time format string checking without triggering
-Wformat-nonliteral.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 tests/libqos/pci-pc.c   |   9 +--
 tests/libqtest.c        |   7 +-
 tests/migration-test.c  |   8 +--
 tests/test-qga.c        | 150 ++++++++++++++++++----------------------
 tests/tpm-util.c        |   9 +--
 tests/vhost-user-test.c |   6 +-
 6 files changed, 77 insertions(+), 112 deletions(-)

diff --git a/tests/libqos/pci-pc.c b/tests/libqos/pci-pc.c
index a7803308b7..585f5289ec 100644
--- a/tests/libqos/pci-pc.c
+++ b/tests/libqos/pci-pc.c
@@ -160,14 +160,9 @@ void qpci_free_pc(QPCIBus *bus)
 void qpci_unplug_acpi_device_test(const char *id, uint8_t slot)
 {
     QDict *response;
-    char *cmd;
 
-    cmd = g_strdup_printf("{'execute': 'device_del',"
-                          " 'arguments': {"
-                          "   'id': '%s'"
-                          "}}", id);
-    response = qmp(cmd);
-    g_free(cmd);
+    response = qmp("{'execute': 'device_del', 'arguments': {'id': %s}}",
+                   id);
     g_assert(response);
     g_assert(!qdict_haskey(response, "error"));
     qobject_unref(response);
diff --git a/tests/libqtest.c b/tests/libqtest.c
index 3bfb062fcb..e36cc5ede3 100644
--- a/tests/libqtest.c
+++ b/tests/libqtest.c
@@ -1079,12 +1079,9 @@ void qtest_qmp_device_add(const char *driver, const char *id, const char *fmt,
 void qtest_qmp_device_del(const char *id)
 {
     QDict *response1, *response2, *event = NULL;
-    char *cmd;
 
-    cmd = g_strdup_printf("{'execute': 'device_del',"
-                          " 'arguments': { 'id': '%s' }}", id);
-    response1 = qmp(cmd);
-    g_free(cmd);
+    response1 = qmp("{'execute': 'device_del', 'arguments': {'id': %s}}",
+                    id);
     g_assert(response1);
     g_assert(!qdict_haskey(response1, "error"));
 
diff --git a/tests/migration-test.c b/tests/migration-test.c
index e079e0bdb6..c6c7089ce1 100644
--- a/tests/migration-test.c
+++ b/tests/migration-test.c
@@ -529,14 +529,12 @@ static void test_migrate_end(QTestState *from, QTestState *to, bool test_dest)
 static void deprecated_set_downtime(QTestState *who, const double value)
 {
     QDict *rsp;
-    gchar *cmd;
     char *expected;
     int64_t result_int;
 
-    cmd = g_strdup_printf("{ 'execute': 'migrate_set_downtime',"
-                          "'arguments': { 'value': %g } }", value);
-    rsp = qtest_qmp(who, cmd);
-    g_free(cmd);
+    rsp = qtest_qmp(who,
+                    "{ 'execute': 'migrate_set_downtime',"
+                    " 'arguments': { 'value': %f } }", value);
     g_assert(qdict_haskey(rsp, "return"));
     qobject_unref(rsp);
     result_int = value * 1000L;
diff --git a/tests/test-qga.c b/tests/test-qga.c
index d638b1571a..c552cc0125 100644
--- a/tests/test-qga.c
+++ b/tests/test-qga.c
@@ -146,12 +146,11 @@ static void test_qga_sync_delimited(gconstpointer fix)
     guint32 v, r = g_random_int();
     unsigned char c;
     QDict *ret;
-    gchar *cmd;
 
-    cmd = g_strdup_printf("\xff{'execute': 'guest-sync-delimited',"
-                          " 'arguments': {'id': %u } }", r);
-    qmp_fd_send(fixture->fd, cmd);
-    g_free(cmd);
+    qmp_fd_send(fixture->fd,
+                "\xff{'execute': 'guest-sync-delimited',"
+                " 'arguments': {'id': %u } }",
+                r);
 
     /*
      * Read and ignore garbage until resynchronized.
@@ -188,7 +187,6 @@ static void test_qga_sync(gconstpointer fix)
     const TestFixture *fixture = fix;
     guint32 v, r = g_random_int();
     QDict *ret;
-    gchar *cmd;
 
     /*
      * TODO guest-sync is inherently limited: we cannot distinguish
@@ -201,10 +199,9 @@ static void test_qga_sync(gconstpointer fix)
      * invalid JSON. Testing of '\xff' handling is done in
      * guest-sync-delimited instead.
      */
-    cmd = g_strdup_printf("{'execute': 'guest-sync',"
-                          " 'arguments': {'id': %u } }", r);
-    ret = qmp_fd(fixture->fd, cmd);
-    g_free(cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-sync', 'arguments': {'id': %u } }",
+                 r);
 
     g_assert_nonnull(ret);
     qmp_assert_no_error(ret);
@@ -428,7 +425,7 @@ static void test_qga_file_ops(gconstpointer fix)
     const TestFixture *fixture = fix;
     const unsigned char helloworld[] = "Hello World!\n";
     const char *b64;
-    gchar *cmd, *path, *enc;
+    gchar *path, *enc;
     unsigned char *dec;
     QDict *ret, *val;
     int64_t id, eof;
@@ -446,10 +443,10 @@ static void test_qga_file_ops(gconstpointer fix)
 
     enc = g_base64_encode(helloworld, sizeof(helloworld));
     /* write */
-    cmd = g_strdup_printf("{'execute': 'guest-file-write',"
-                          " 'arguments': { 'handle': %" PRId64 ","
-                          " 'buf-b64': '%s' } }", id, enc);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-write',"
+                 " 'arguments': { 'handle': %" PRId64 ", 'buf-b64': %s } }",
+                 id, enc);
     g_assert_nonnull(ret);
     qmp_assert_no_error(ret);
 
@@ -459,23 +456,20 @@ static void test_qga_file_ops(gconstpointer fix)
     g_assert_cmpint(count, ==, sizeof(helloworld));
     g_assert_cmpint(eof, ==, 0);
     qobject_unref(ret);
-    g_free(cmd);
 
     /* flush */
-    cmd = g_strdup_printf("{'execute': 'guest-file-flush',"
-                          " 'arguments': {'handle': %" PRId64 "} }",
-                          id);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-flush',"
+                 " 'arguments': {'handle': %" PRId64 "} }",
+                 id);
     qobject_unref(ret);
-    g_free(cmd);
 
     /* close */
-    cmd = g_strdup_printf("{'execute': 'guest-file-close',"
-                          " 'arguments': {'handle': %" PRId64 "} }",
-                          id);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-close',"
+                 " 'arguments': {'handle': %" PRId64 "} }",
+                 id);
     qobject_unref(ret);
-    g_free(cmd);
 
     /* check content */
     path = g_build_filename(fixture->test_dir, "foo", NULL);
@@ -497,10 +491,10 @@ static void test_qga_file_ops(gconstpointer fix)
     qobject_unref(ret);
 
     /* read */
-    cmd = g_strdup_printf("{'execute': 'guest-file-read',"
-                          " 'arguments': { 'handle': %" PRId64 "} }",
-                          id);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-read',"
+                 " 'arguments': { 'handle': %" PRId64 "} }",
+                 id);
     val = qdict_get_qdict(ret, "return");
     count = qdict_get_int(val, "count");
     eof = qdict_get_bool(val, "eof");
@@ -510,14 +504,13 @@ static void test_qga_file_ops(gconstpointer fix)
     g_assert_cmpstr(b64, ==, enc);
 
     qobject_unref(ret);
-    g_free(cmd);
     g_free(enc);
 
     /* read eof */
-    cmd = g_strdup_printf("{'execute': 'guest-file-read',"
-                          " 'arguments': { 'handle': %" PRId64 "} }",
-                          id);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-read',"
+                 " 'arguments': { 'handle': %" PRId64 "} }",
+                 id);
     val = qdict_get_qdict(ret, "return");
     count = qdict_get_int(val, "count");
     eof = qdict_get_bool(val, "eof");
@@ -526,14 +519,13 @@ static void test_qga_file_ops(gconstpointer fix)
     g_assert(eof);
     g_assert_cmpstr(b64, ==, "");
     qobject_unref(ret);
-    g_free(cmd);
 
     /* seek */
-    cmd = g_strdup_printf("{'execute': 'guest-file-seek',"
-                          " 'arguments': { 'handle': %" PRId64 ", "
-                          " 'offset': %d, 'whence': '%s' } }",
-                          id, 6, "set");
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-seek',"
+                 " 'arguments': { 'handle': %" PRId64 ", "
+                 " 'offset': %d, 'whence': %s } }",
+                 id, 6, "set");
     qmp_assert_no_error(ret);
     val = qdict_get_qdict(ret, "return");
     count = qdict_get_int(val, "position");
@@ -541,13 +533,12 @@ static void test_qga_file_ops(gconstpointer fix)
     g_assert_cmpint(count, ==, 6);
     g_assert(!eof);
     qobject_unref(ret);
-    g_free(cmd);
 
     /* partial read */
-    cmd = g_strdup_printf("{'execute': 'guest-file-read',"
-                          " 'arguments': { 'handle': %" PRId64 "} }",
-                          id);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-read',"
+                 " 'arguments': { 'handle': %" PRId64 "} }",
+                 id);
     val = qdict_get_qdict(ret, "return");
     count = qdict_get_int(val, "count");
     eof = qdict_get_bool(val, "eof");
@@ -560,15 +551,13 @@ static void test_qga_file_ops(gconstpointer fix)
     g_free(dec);
 
     qobject_unref(ret);
-    g_free(cmd);
 
     /* close */
-    cmd = g_strdup_printf("{'execute': 'guest-file-close',"
-                          " 'arguments': {'handle': %" PRId64 "} }",
-                          id);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-close',"
+                 " 'arguments': {'handle': %" PRId64 "} }",
+                 id);
     qobject_unref(ret);
-    g_free(cmd);
 }
 
 static void test_qga_file_write_read(gconstpointer fix)
@@ -576,7 +565,7 @@ static void test_qga_file_write_read(gconstpointer fix)
     const TestFixture *fixture = fix;
     const unsigned char helloworld[] = "Hello World!\n";
     const char *b64;
-    gchar *cmd, *enc;
+    gchar *enc;
     QDict *ret, *val;
     int64_t id, eof;
     gsize count;
@@ -591,10 +580,10 @@ static void test_qga_file_write_read(gconstpointer fix)
 
     enc = g_base64_encode(helloworld, sizeof(helloworld));
     /* write */
-    cmd = g_strdup_printf("{'execute': 'guest-file-write',"
-                          " 'arguments': { 'handle': %" PRId64 ","
-                          " 'buf-b64': '%s' } }", id, enc);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-write',"
+                 " 'arguments': { 'handle': %" PRId64 ","
+                 " 'buf-b64': %s } }", id, enc);
     g_assert_nonnull(ret);
     qmp_assert_no_error(ret);
 
@@ -604,13 +593,12 @@ static void test_qga_file_write_read(gconstpointer fix)
     g_assert_cmpint(count, ==, sizeof(helloworld));
     g_assert_cmpint(eof, ==, 0);
     qobject_unref(ret);
-    g_free(cmd);
 
     /* read (check implicit flush) */
-    cmd = g_strdup_printf("{'execute': 'guest-file-read',"
-                          " 'arguments': { 'handle': %" PRId64 "} }",
-                          id);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-read',"
+                 " 'arguments': { 'handle': %" PRId64 "} }",
+                 id);
     val = qdict_get_qdict(ret, "return");
     count = qdict_get_int(val, "count");
     eof = qdict_get_bool(val, "eof");
@@ -619,14 +607,13 @@ static void test_qga_file_write_read(gconstpointer fix)
     g_assert(eof);
     g_assert_cmpstr(b64, ==, "");
     qobject_unref(ret);
-    g_free(cmd);
 
     /* seek to 0 */
-    cmd = g_strdup_printf("{'execute': 'guest-file-seek',"
-                          " 'arguments': { 'handle': %" PRId64 ", "
-                          " 'offset': %d, 'whence': '%s' } }",
-                          id, 0, "set");
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-seek',"
+                 " 'arguments': { 'handle': %" PRId64 ", "
+                 " 'offset': %d, 'whence': %s } }",
+                 id, 0, "set");
     qmp_assert_no_error(ret);
     val = qdict_get_qdict(ret, "return");
     count = qdict_get_int(val, "position");
@@ -634,13 +621,12 @@ static void test_qga_file_write_read(gconstpointer fix)
     g_assert_cmpint(count, ==, 0);
     g_assert(!eof);
     qobject_unref(ret);
-    g_free(cmd);
 
     /* read */
-    cmd = g_strdup_printf("{'execute': 'guest-file-read',"
-                          " 'arguments': { 'handle': %" PRId64 "} }",
-                          id);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-read',"
+                 " 'arguments': { 'handle': %" PRId64 "} }",
+                 id);
     val = qdict_get_qdict(ret, "return");
     count = qdict_get_int(val, "count");
     eof = qdict_get_bool(val, "eof");
@@ -649,16 +635,14 @@ static void test_qga_file_write_read(gconstpointer fix)
     g_assert(eof);
     g_assert_cmpstr(b64, ==, enc);
     qobject_unref(ret);
-    g_free(cmd);
     g_free(enc);
 
     /* close */
-    cmd = g_strdup_printf("{'execute': 'guest-file-close',"
-                          " 'arguments': {'handle': %" PRId64 "} }",
-                          id);
-    ret = qmp_fd(fixture->fd, cmd);
+    ret = qmp_fd(fixture->fd,
+                 "{'execute': 'guest-file-close',"
+                 " 'arguments': {'handle': %" PRId64 "} }",
+                 id);
     qobject_unref(ret);
-    g_free(cmd);
 }
 
 static void test_qga_get_time(gconstpointer fix)
@@ -814,7 +798,6 @@ static void test_qga_guest_exec(gconstpointer fix)
     int64_t pid, now, exitcode;
     gsize len;
     bool exited;
-    char *cmd;
 
     /* exec 'echo foo bar' */
     ret = qmp_fd(fixture->fd, "{'execute': 'guest-exec', 'arguments': {"
@@ -829,10 +812,10 @@ static void test_qga_guest_exec(gconstpointer fix)
 
     /* wait for completion */
     now = g_get_monotonic_time();
-    cmd = g_strdup_printf("{'execute': 'guest-exec-status',"
-                          " 'arguments': { 'pid': %" PRId64 " } }", pid);
     do {
-        ret = qmp_fd(fixture->fd, cmd);
+        ret = qmp_fd(fixture->fd,
+                     "{'execute': 'guest-exec-status',"
+                     " 'arguments': { 'pid': %" PRId64 " } }", pid);
         g_assert_nonnull(ret);
         val = qdict_get_qdict(ret, "return");
         exited = qdict_get_bool(val, "exited");
@@ -842,7 +825,6 @@ static void test_qga_guest_exec(gconstpointer fix)
     } while (!exited &&
              g_get_monotonic_time() < now + 5 * G_TIME_SPAN_SECOND);
     g_assert(exited);
-    g_free(cmd);
 
     /* check stdout */
     exitcode = qdict_get_int(val, "exitcode");
diff --git a/tests/tpm-util.c b/tests/tpm-util.c
index 672cedf905..3bd2887f1e 100644
--- a/tests/tpm-util.c
+++ b/tests/tpm-util.c
@@ -239,13 +239,10 @@ void tpm_util_swtpm_kill(GPid pid)
 void tpm_util_migrate(QTestState *who, const char *uri)
 {
     QDict *rsp;
-    gchar *cmd;
 
-    cmd = g_strdup_printf("{ 'execute': 'migrate',"
-                          "'arguments': { 'uri': '%s' } }",
-                          uri);
-    rsp = qtest_qmp(who, cmd);
-    g_free(cmd);
+    rsp = qtest_qmp(who,
+                    "{ 'execute': 'migrate', 'arguments': { 'uri': %s } }",
+                    uri);
     g_assert(qdict_haskey(rsp, "return"));
     qobject_unref(rsp);
 }
diff --git a/tests/vhost-user-test.c b/tests/vhost-user-test.c
index fecc832d99..ca6251f5f8 100644
--- a/tests/vhost-user-test.c
+++ b/tests/vhost-user-test.c
@@ -709,11 +709,7 @@ static void test_migrate(void)
     g_assert(qdict_haskey(rsp, "return"));
     qobject_unref(rsp);
 
-    cmd = g_strdup_printf("{ 'execute': 'migrate',"
-                          "'arguments': { 'uri': '%s' } }",
-                          uri);
-    rsp = qmp(cmd);
-    g_free(cmd);
+    rsp = qmp("{ 'execute': 'migrate', 'arguments': { 'uri': %s } }", uri);
     g_assert(qdict_haskey(rsp, "return"));
     qobject_unref(rsp);
 
-- 
2.17.1