libqmi-glib,utils: new read/write methods for uint types of arbitrary size

The new qmi_utils_(read|write)_sized_guint_(from|to)_buffer() methods allow
reading unsigned integers of non-standard sizes, like for example 6 bytes. The
read/written number is always provided as a guint64 value.

3 files changed, 104 insertions, 0 deletions

diff --git a/libqmi-glib/qmi-utils.c b/libqmi-glib/qmi-utils.c
index 0e99469..39cf285 100644
--- a/libqmi-glib/qmi-utils.c
+++ b/libqmi-glib/qmi-utils.c
@@ -190,6 +190,26 @@ qmi_utils_read_gint64_from_buffer (guint8  **buffer,
 }
 
 void
+qmi_utils_read_sized_guint_from_buffer (guint8  **buffer,
+                                        guint16  *buffer_size,
+                                        guint     n_bytes,
+                                        guint64  *out)
+{
+    guint64 tmp = 0;
+
+    g_assert (out != NULL);
+    g_assert (buffer != NULL);
+    g_assert (buffer_size != NULL);
+    g_assert (*buffer_size >= n_bytes);
+
+    memcpy (&tmp, *buffer, n_bytes);
+    *out = GUINT64_FROM_LE (tmp);
+
+    *buffer = &((*buffer)[n_bytes]);
+    *buffer_size = (*buffer_size) - n_bytes;
+}
+
+void
 qmi_utils_write_guint8_to_buffer (guint8  **buffer,
                                   guint16  *buffer_size,
                                   guint8   *in)
@@ -318,6 +338,26 @@ qmi_utils_write_gint64_to_buffer (guint8  **buffer,
 }
 
 void
+qmi_utils_write_sized_guint_to_buffer (guint8  **buffer,
+                                       guint16  *buffer_size,
+                                       guint     n_bytes,
+                                       guint64  *in)
+{
+    guint64 tmp;
+
+    g_assert (in != NULL);
+    g_assert (buffer != NULL);
+    g_assert (buffer_size != NULL);
+    g_assert (*buffer_size >= n_bytes);
+
+    tmp = GUINT64_TO_LE (*in);
+    memcpy (*buffer, &tmp, n_bytes);
+
+    *buffer = &((*buffer)[n_bytes]);
+    *buffer_size = (*buffer_size) - n_bytes;
+}
+
+void
 qmi_utils_read_string_from_buffer (guint8   **buffer,
                                    guint16   *buffer_size,
                                    gboolean   length_prefix,
diff --git a/libqmi-glib/qmi-utils.h b/libqmi-glib/qmi-utils.h
index 8feda22..d1dc0d4 100644
--- a/libqmi-glib/qmi-utils.h
+++ b/libqmi-glib/qmi-utils.h
@@ -64,6 +64,11 @@ void qmi_utils_read_gint64_from_buffer  (guint8  **buffer,
                                          guint16  *buffer_size,
                                          gint64   *out);
 
+void qmi_utils_read_sized_guint_from_buffer (guint8  **buffer,
+                                             guint16  *buffer_size,
+                                             guint     n_bytes,
+                                             guint64  *out);
+
 void qmi_utils_write_guint8_to_buffer (guint8  **buffer,
                                        guint16  *buffer_size,
                                        guint8   *in);
@@ -92,6 +97,11 @@ void qmi_utils_write_gint64_to_buffer  (guint8  **buffer,
                                         guint16  *buffer_size,
                                         gint64   *in);
 
+void qmi_utils_write_sized_guint_to_buffer (guint8  **buffer,
+                                            guint16  *buffer_size,
+                                            guint     n_bytes,
+                                            guint64  *in);
+
 /* Reading/Writing string variables */
 
 void qmi_utils_read_string_from_buffer (guint8   **buffer,
diff --git a/libqmi-glib/test/test-utils.c b/libqmi-glib/test/test-utils.c
index 290b48d..90d6759 100644
--- a/libqmi-glib/test/test-utils.c
+++ b/libqmi-glib/test/test-utils.c
@@ -297,6 +297,58 @@ test_utils_int64 (void)
     g_assert (memcmp (in_buffer, out_buffer, sizeof (in_buffer)) == 0);
 }
 
+static void
+common_test_utils_uint_sized (guint n_bytes)
+{
+    static guint8 in_buffer[8] = {
+        0x0F, 0x50, 0xEB, 0xE2, 0xB6, 0x00, 0x00, 0x00
+    };
+    guint64 value = 0x000000B6E2EB500F;
+    guint8 expected_out_buffer[8] = { 0 };
+    guint8 out_buffer[8] = { 0 };
+
+    guint64 tmp;
+    guint i;
+    guint16 in_buffer_size;
+    guint8 *in_buffer_walker;
+    guint16 out_buffer_size;
+    guint8 *out_buffer_walker;
+
+    /* Build expected intermediate value */
+    tmp = 0xFF;
+    for (i = 1; i < n_bytes; i++) {
+        tmp <<= 8;
+        tmp |= 0xFF;
+    }
+    value &= tmp;
+
+    /* Build expected output buffer */
+    memcpy (expected_out_buffer, in_buffer, n_bytes);
+
+    in_buffer_size = sizeof (in_buffer);
+    in_buffer_walker = &in_buffer[0];
+    out_buffer_size = sizeof (out_buffer);
+    out_buffer_walker = &out_buffer[0];
+    i = 0;
+
+    qmi_utils_read_sized_guint_from_buffer (&in_buffer_walker, &in_buffer_size, n_bytes, &tmp);
+    g_assert (tmp == value);
+    qmi_utils_write_sized_guint_to_buffer (&out_buffer_walker, &out_buffer_size, n_bytes, &tmp);
+
+    g_assert_cmpuint (out_buffer_size, ==, 8 - n_bytes);
+    g_assert (memcmp (expected_out_buffer, out_buffer, sizeof (expected_out_buffer)) == 0);
+}
+
+static void
+test_utils_uint_sized (void)
+{
+    guint i;
+
+    for (i = 1; i <= 8; i++) {
+        common_test_utils_uint_sized (i);
+    }
+}
+
 int main (int argc, char **argv)
 {
     g_type_init ();
@@ -311,5 +363,7 @@ int main (int argc, char **argv)
     g_test_add_func ("/libqmi-glib/utils/uint64", test_utils_uint64);
     g_test_add_func ("/libqmi-glib/utils/int64",  test_utils_int64);
 
+    g_test_add_func ("/libqmi-glib/utils/uint-sized", test_utils_uint_sized);
+
     return g_test_run ();
 }