[PATCH wayland v3 4/5] Add support for signed 24.8 decimal numbers

Daniel Stone daniel at fooishbar.org
Fri May 4 03:21:22 PDT 2012


signed_24_8 is a signed decimal type which offers a sign bit, 23 bits of
integer precision, and 8 bits of decimal precision.  This is converted
to double on the C API side, as passing through varargs involves an
implicit type promotion to double anyway.

Signed-off-by: Daniel Stone <daniel at fooishbar.org>
---
 src/Makefile.am         |    4 ++--
 src/connection.c        |   20 +++++++++++++++++++-
 src/scanner.c           |    9 +++++++++
 src/wayland-server.h    |    1 +
 src/wayland-util.h      |    7 +++++++
 tests/connection-test.c |   42 ++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 80 insertions(+), 3 deletions(-)

v3: Use a new typedef instead of double.

diff --git a/src/Makefile.am b/src/Makefile.am
index c685885..f93954e 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -18,7 +18,7 @@ libwayland_util_la_SOURCES =			\
 	wayland-os.h				\
 	wayland-private.h
 
-libwayland_server_la_LIBADD = $(FFI_LIBS) libwayland-util.la -lrt
+libwayland_server_la_LIBADD = $(FFI_LIBS) libwayland-util.la -lrt -lm
 libwayland_server_la_SOURCES =			\
 	wayland-protocol.c			\
 	wayland-server.c			\
@@ -26,7 +26,7 @@ libwayland_server_la_SOURCES =			\
 	data-device.c				\
 	event-loop.c
 
-libwayland_client_la_LIBADD = $(FFI_LIBS) libwayland-util.la -lrt
+libwayland_client_la_LIBADD = $(FFI_LIBS) libwayland-util.la -lrt -lm
 libwayland_client_la_SOURCES =			\
 	wayland-protocol.c			\
 	wayland-client.c
diff --git a/src/connection.c b/src/connection.c
index 06cc66f..8d16dc4 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -22,6 +22,7 @@
 
 #define _GNU_SOURCE
 
+#include <math.h>
 #include <stdlib.h>
 #include <stdint.h>
 #include <string.h>
@@ -428,6 +429,13 @@ wl_closure_vmarshal(struct wl_closure *closure,
 
 	for (i = 2; i < count; i++) {
 		switch (message->signature[i - 2]) {
+		case 'f':
+			closure->types[i] = &ffi_type_sint32;
+			closure->args[i] = p;
+			if (end - p < 1)
+				goto err;
+			*p++ = va_arg(ap, wl_signed_24_8_t);
+			break;
 		case 'u':
 			closure->types[i] = &ffi_type_uint32;
 			closure->args[i] = p;
@@ -611,6 +619,10 @@ wl_connection_demarshal(struct wl_connection *connection,
 			closure->types[i] = &ffi_type_sint32;
 			closure->args[i] = p++;
 			break;
+		case 'f':
+			closure->types[i] = &ffi_type_sint32;
+			closure->args[i] = p++;
+			break;
 		case 's':
 			closure->types[i] = &ffi_type_pointer;
 			length = *p++;
@@ -812,6 +824,7 @@ void
 wl_closure_print(struct wl_closure *closure, struct wl_object *target, int send)
 {
 	union wl_value *value;
+	int32_t si;
 	int i;
 	struct timespec tp;
 	unsigned int time;
@@ -835,7 +848,12 @@ wl_closure_print(struct wl_closure *closure, struct wl_object *target, int send)
 			fprintf(stderr, "%u", value->uint32);
 			break;
 		case 'i':
-			fprintf(stderr, "%d", value->uint32);
+			si = (int32_t) value->uint32;
+			fprintf(stderr, "%d", si);
+			break;
+		case 'f':
+			si = (int32_t) value->uint32;
+			fprintf(stderr, "%f", wl_signed_24_8_to_double(si));
 			break;
 		case 's':
 			fprintf(stderr, "\"%s\"", value->string);
diff --git a/src/scanner.c b/src/scanner.c
index 3fba0ad..a13b943 100644
--- a/src/scanner.c
+++ b/src/scanner.c
@@ -82,6 +82,7 @@ enum arg_type {
 	NEW_ID,
 	INT,
 	UNSIGNED,
+	SIGNED_24_8,
 	STRING,
 	OBJECT,
 	ARRAY,
@@ -296,6 +297,8 @@ start_element(void *data, const char *element_name, const char **atts)
 			arg->type = INT;
 		else if (strcmp(type, "uint") == 0)
 			arg->type = UNSIGNED;
+		else if (strcmp(type, "signed_24_8") == 0)
+			arg->type = SIGNED_24_8;
 		else if (strcmp(type, "string") == 0)
 			arg->type = STRING;
 		else if (strcmp(type, "array") == 0)
@@ -446,6 +449,9 @@ emit_type(struct arg *a)
 	case UNSIGNED:
 		printf("uint32_t ");
 		break;
+	case SIGNED_24_8:
+		printf("wl_signed_24_8_t ");
+		break;
 	case STRING:
 		printf("const char *");
 		break;
@@ -953,6 +959,9 @@ emit_messages(struct wl_list *message_list,
 			case UNSIGNED:
 				printf("u");
 				break;
+			case SIGNED_24_8:
+				printf("f");
+				break;
 			case STRING:
 				printf("s");
 				break;
diff --git a/src/wayland-server.h b/src/wayland-server.h
index 9d4f58e..73c6f57 100644
--- a/src/wayland-server.h
+++ b/src/wayland-server.h
@@ -281,6 +281,7 @@ struct wl_input_device {
  * The variable arguments' types are:
  * - type=uint: 	uint32_t
  * - type=int:		int32_t
+ * - type=signed_24_8:	wl_signed_24_8_t
  * - type=string:	(const char *) to a nil-terminated string
  * - type=array:	(struct wl_array *)
  * - type=fd:		int, that is an open file descriptor
diff --git a/src/wayland-util.h b/src/wayland-util.h
index 1b8fd4b..ebc60b5 100644
--- a/src/wayland-util.h
+++ b/src/wayland-util.h
@@ -165,6 +165,13 @@ void wl_array_release(struct wl_array *array);
 void *wl_array_add(struct wl_array *array, size_t size);
 void wl_array_copy(struct wl_array *array, struct wl_array *source);
 
+
+typedef int32_t wl_signed_24_8_t;
+#define wl_signed_24_8_to_double(x) ((double) (x) / 256.0)
+#define wl_signed_24_8_from_double(x) ((int32_t) round(x * 256.0))
+#define wl_signed_24_8_to_int(x) (x / 256)
+#define wl_signed_24_8_from_int(x) (x * 256)
+
 #ifdef  __cplusplus
 }
 #endif
diff --git a/tests/connection-test.c b/tests/connection-test.c
index 54ac423..608c7f6 100644
--- a/tests/connection-test.c
+++ b/tests/connection-test.c
@@ -20,6 +20,7 @@
  * OF THIS SOFTWARE.
  */
 
+#include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
@@ -288,6 +289,17 @@ validate_demarshal_h(struct marshal_data *data,
 }
 
 static void
+validate_demarshal_f(struct marshal_data *data,
+		     struct wl_object *object, wl_signed_24_8_t f)
+{
+	double in = wl_signed_24_8_to_double(data->value.i);
+	double wire = wl_signed_24_8_to_double(f);
+
+	assert(data->value.i == f);
+	assert(fabs(in - wire) <= 1.0 / 256.0);
+}
+
+static void
 demarshal(struct marshal_data *data, const char *format,
 	  uint32_t *msg, void (*func)(void))
 {
@@ -335,6 +347,24 @@ TEST(connection_demarshal)
 	memcpy(&msg[3], data.value.s, msg[2]);
 	demarshal(&data, "s", msg, (void *) validate_demarshal_s);
 
+	data.value.i = wl_signed_24_8_from_double(5678.1234);
+	msg[0] = 400200;
+	msg[1] = 12;
+	msg[2] = data.value.i;
+	demarshal(&data, "f", msg, (void *) validate_demarshal_f);
+
+	data.value.i = wl_signed_24_8_from_double(-90000.2390);
+	msg[0] = 400200;
+	msg[1] = 12;
+	msg[2] = data.value.i;
+	demarshal(&data, "f", msg, (void *) validate_demarshal_f);
+
+	data.value.i = wl_signed_24_8_from_int((1 << 23) - 1);
+	msg[0] = 400200;
+	msg[1] = 12;
+	msg[2] = data.value.i;
+	demarshal(&data, "f", msg, (void *) validate_demarshal_f);
+
 	release_marshal_data(&data);
 }
 
@@ -400,6 +430,18 @@ TEST(connection_marshal_demarshal)
 	marshal_demarshal(&data, (void *) validate_demarshal_h,
 			  8, "h", data.value.h);
 
+	data.value.i = wl_signed_24_8_from_double(1234.5678);
+	marshal_demarshal(&data, (void *) validate_demarshal_f,
+	                  12, "f", data.value.i);
+
+	data.value.i = wl_signed_24_8_from_double(-90000.2390);
+	marshal_demarshal(&data, (void *) validate_demarshal_f,
+	                  12, "f", data.value.i);
+
+	data.value.i = wl_signed_24_8_from_double((1 << 23) - 1 + 0.0941);
+	marshal_demarshal(&data, (void *) validate_demarshal_f,
+	                  12, "f", data.value.i);
+
 	release_marshal_data(&data);
 }
 
-- 
1.7.10



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