Add example for the weak linking

buildandtest

@@ -14,3 +14,7 @@ build/fff_test_glob_c
 build/fff_test_glob_cpp --gtest_output=xml:build/test_global_results.xml
 build/driver_testing --gtest_output=xml:build/driver_testing.xml
 build/driver_testing_fff  --gtest_output=xml:build/driver_testing_fff.xml
+build/weak_linking/test_display
+build/weak_linking/test_sensor
+build/weak_linking/test_main
+

examples/Makefile

@@ -1,7 +1,9 @@
 all: 
 	cd embedded_ui; $(MAKE) all
 	cd driver_testing; $(MAKE) all
-
+	cd weak_linking; $(MAKE) all
 clean: 
 	cd embedded_ui; $(MAKE) clean
 	cd driver_testing; $(MAKE) clean
+	cd weak_linking; $(MAKE) clean
+

examples/weak_linking/Makefile

@@ -0,0 +1,48 @@
+
+BUILD_DIR = ../../build
+INCLUDE_DIRS = -I "../../" -I "./src/"
+
+BUILD_DIR_FAKE =  $(BUILD_DIR)/weak_linking
+CC = gcc
+WEAK_FLAGS=-Wall -DFFF_FUNCTION_ATTRIBUTES="__attribute__((weak))"
+
+$(BUILD_DIR_FAKE)/%.o: test/%.c
+	@echo "Compiling "$@
+	$(CC) $(WEAK_FLAGS) $(INCLUDE_DIRS) -g -O0 -c $< -o $@ 
+	
+
+
+
+FAKE_OBJECTS = $(BUILD_DIR_FAKE)/display.fake.o $(BUILD_DIR_FAKE)/sensor.fake.o $(BUILD_DIR_FAKE)/sensor.fake.o $(BUILD_DIR_FAKE)/error.fake.o  $(BUILD_DIR_FAKE)/bus.fake.o $(BUILD_DIR_FAKE)/test_common.o
+
+TEST_BINARIES = $(BUILD_DIR_FAKE)/test_main $(BUILD_DIR_FAKE)/test_display $(BUILD_DIR_FAKE)/test_sensor 
+mkdir:
+	mkdir -p $(BUILD_DIR_FAKE)/
+
+clean:
+	rm -rf $(BUILD_DIR_FAKE)/ 
+
+$(BUILD_DIR_FAKE)/libfakes.a:  $(FAKE_OBJECTS)
+	ar r $@  $^
+
+#
+# First case where we need __weak__ linking: if we have the build objects (for some reason) in order where the fake
+# object compes first 
+$(BUILD_DIR_FAKE)/test_display: ./test/display.test.c $(BUILD_DIR_FAKE)/libfakes.a ./src/display.c
+	$(CC) $(WEAK_FLAGS) $(INCLUDE_DIRS) -o $@ $^
+
+#
+# Second case where we need weak linking: If we use a object from the fake object -> gcc linker will include it
+# One can go around also in another way: by making the fake objects in separate files. 
+#
+$(BUILD_DIR_FAKE)/test_sensor: ./test/sensor.test.c ./src/sensor.c $(BUILD_DIR_FAKE)/libfakes.a
+	$(CC) $(WEAK_FLAGS) $(INCLUDE_DIRS) -o $@ $^
+
+#
+# Third case: we want to mock one function but not all.
+#
+$(BUILD_DIR_FAKE)/test_main: ./test/main.test.c ./src/main.c $(BUILD_DIR_FAKE)/libfakes.a
+	$(CC) $(WEAK_FLAGS) $(INCLUDE_DIRS) -o $@ $^
+
+
+all: mkdir $(TEST_BINARIES)

examples/weak_linking/src/bus.c

@@ -0,0 +1,32 @@
+#pragma once
+
+uint16_t* BUS_REGISTER_BASE = (uint16_t*)0xFADEFADE;
+
+typedef struct
+{
+    uint16_t action;
+    uint16_t reg;
+    uint8_t  input;
+    uint8_t  output
+} BusDevice;
+
+BusDevice* BUS = (BusDevice*)BUS_REGISTER_BASE;
+
+bool bus_read_write( uint8_t dev, uint8_t registry, uint8_t* buffer, int len, bool assume_echo )
+{
+    
+    // well something that we dont want to run, since the emulation would be hard
+    BUS->action = 0x01;
+    BUS->reg = registry;
+    for ( int loop =0 ; loop < len; loop ++ )
+    {
+        char output = buffer[loop];
+        BUS->output  = output;
+        buffer[loop] = BUS->input;
+        
+        if ( ( assume_echo ) && ( buffer[loop] != output ) )
+            return false;
+    }
+    return true;
+}
+

examples/weak_linking/src/bus.h

@@ -0,0 +1,5 @@
+#pragma once
+#include "error.h"
+
+bool bus_read_write( uint8_t dev, uint8_t registry, uint8_t* buffer, int len, bool assume_echo );
+bool bus_write( uint8_t dev, uint8_t registry, const uint8_t* buffer, int len, bool assume_echo );

examples/weak_linking/src/display.c

@@ -0,0 +1,32 @@
+#include <string.h>
+
+#include "display.h"
+#include "bus.h"
+
+
+#define DISPLAY_ADDRESS     0xAF
+#define DISPLAY_REG_INIT    0x10
+#define DISPLAY_REG_UPDATE  0x20
+
+bool display_init()
+{
+    char init_config[] = { 0xDE, 0xFE, 0x00 };
+    bus_read_write( DISPLAY_ADDRESS, DISPLAY_REG_INIT, (uint8_t*)init_config, 3, false );
+    
+    if (init_config[2] != 0x10)
+        return false;
+    
+    return true;
+}
+
+
+void display_update( const char* info )
+{
+    int len = strlen( info );
+    
+    if ( bus_write( DISPLAY_ADDRESS, DISPLAY_REG_UPDATE, (const uint8_t*)info, len, true ) != true )
+    {
+        runtime_error("display update failed!");
+    }
+}
+

examples/weak_linking/src/display.h

@@ -0,0 +1,7 @@
+#pragma once
+#include "error.h"
+
+bool display_init();
+void display_update( const char* info );
+
+

examples/weak_linking/src/error.c

@@ -0,0 +1,12 @@
+#include <assert.h>
+#include "error.h"
+
+// Function void runtime_error( const char* msg ) is defined on another file.
+
+char* runtime_error_nice_print( const char* msg )
+{
+    char* buffer = malloc(512);
+    snprintf(buffer, 512, "Got error: %s", msg );
+    buffer[511] = 0;
+    return buffer;
+}

examples/weak_linking/src/error.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <stdint.h>
+#include <stdbool.h>
+
+void runtime_error( const char* msg );
+char* runtime_error_nice_print( const char* msg );

examples/weak_linking/src/main.c

@@ -0,0 +1,32 @@
+
+#include "display.h"
+#include "sensor.h"
+#include <stdlib.h>
+#include <stdio.h>
+
+
+void give_error( const char* msg )
+{
+    char* buffer = runtime_error_nice_print( msg );
+    runtime_error( buffer );
+    free(buffer);
+}
+
+int update_main( void )
+{
+    
+    if ( !sensor_init() )
+        runtime_error("sensor init failed");
+    
+    if ( !display_init() )
+        runtime_error("display init failed");
+    
+    // Well i guess normally we would have here a for loop.
+    char buffer[32];
+    float reading = sensor_read();
+    snprintf( buffer, 32, "Sensor: %0.1f", reading );
+    display_update( buffer );
+    return 0;
+    
+}
+

examples/weak_linking/src/sensor.c

@@ -0,0 +1,32 @@
+
+#include <string.h>
+
+#include "sensor.h"
+#include "bus.h"
+
+#define SENSOR_ADDRESS 0xAA
+#define SENSOR_REG_READ 0xF0 
+float LOCAL_buffer[4];
+
+bool sensor_init()
+{
+    memset( LOCAL_buffer, 0x00, sizeof(LOCAL_buffer));
+    return true;
+}
+
+float sensor_read()
+{
+    char data[4] = { 0xFF, 0xFF, 0x00, 0x00 };
+    bus_read_write( SENSOR_ADDRESS, SENSOR_REG_READ, (uint8_t*)&data, 4, false );
+    
+    if (data[0] != 0x10)
+    {
+        runtime_error("sensor read failed");
+    }
+    
+    float ret_value = data[1] + data[2] / 256.0;
+    return ret_value;
+}
+
+
+

examples/weak_linking/src/sensor.h

@@ -0,0 +1,6 @@
+#pragma once
+#include "error.h"
+
+bool sensor_init();
+float sensor_read();
+

examples/weak_linking/test/bus.fake.c

@@ -0,0 +1,5 @@
+
+
+#include "bus.fake.h"
+DEFINE_FAKE_VALUE_FUNC( bool, bus_read_write, uint8_t, uint8_t, uint8_t*, int, bool );
+DEFINE_FAKE_VALUE_FUNC( bool, bus_write, uint8_t, uint8_t, const uint8_t*, int, bool );

examples/weak_linking/test/bus.fake.h

@@ -0,0 +1,11 @@
+
+
+#ifndef _AUTOMOCK_BUS_H
+#define _AUTOMOCK_BUS_H
+
+#include "fff.h"
+#include "bus.h"
+
+DECLARE_FAKE_VALUE_FUNC( bool, bus_read_write, uint8_t, uint8_t, uint8_t*, int, bool );
+DECLARE_FAKE_VALUE_FUNC( bool, bus_write, uint8_t, uint8_t, const uint8_t*, int, bool );
+#endif // _AUTOMOCK_BUS_H

examples/weak_linking/test/display.fake.c

@@ -0,0 +1,4 @@
+
+#include "display.fake.h"
+DEFINE_FAKE_VALUE_FUNC( bool, display_init );
+DEFINE_FAKE_VOID_FUNC( display_update, const char* );

examples/weak_linking/test/display.fake.h

@@ -0,0 +1,11 @@
+
+#ifndef _AUTOMOCK_DISPLAY_H
+#define _AUTOMOCK_DISPLAY_H
+
+#include "fff.h"
+#include "display.h"
+
+DECLARE_FAKE_VALUE_FUNC( bool, display_init );
+DECLARE_FAKE_VOID_FUNC( display_update, const char* );
+
+#endif // _AUTOMOCK_DISPLAY_H

examples/weak_linking/test/display.test.c

@@ -0,0 +1,27 @@
+
+#include "test_common.h"
+
+#include "display.h"
+
+DEFINE_FFF_GLOBALS;
+
+
+int main(void)
+{
+   init_tests(); // will reset common and hook errors to asserts
+   
+   GLOBAL_TEST_bus_read_ret[2] = 0x10;
+   assert( display_init() == true );
+   assert( bus_read_write_fake.call_count == 1);
+   
+   display_update( "TEST INFO" );
+   assert( bus_read_write_fake.call_count == 1 );
+   assert( bus_write_fake.call_count == 1 );
+
+   GLOBAL_TEST_bus_read_ret[2] = 0x00;
+   assert( display_init() == false );
+   
+   printf("Test " __FILE__ " ok\n");
+   return 0;
+
+}

examples/weak_linking/test/error.fake.c

@@ -0,0 +1,4 @@
+
+#include "error.fake.h"
+DEFINE_FAKE_VOID_FUNC( runtime_error, const char* );
+DEFINE_FAKE_VALUE_FUNC( char*, runtime_error_nice_print, const char* );

examples/weak_linking/test/error.fake.h

@@ -0,0 +1,11 @@
+
+#ifndef _AUTOMOCK_ERROR_H
+#define _AUTOMOCK_ERROR_H
+
+#include "fff.h"
+#include "error.h"
+
+DECLARE_FAKE_VOID_FUNC( runtime_error, const char* );
+DECLARE_FAKE_VALUE_FUNC( char*, runtime_error_nice_print, const char* );
+
+#endif // _AUTOMOCK_ERROR_H

examples/weak_linking/test/main.test.c

@@ -0,0 +1,28 @@
+
+#include "display.fake.h"
+#include "sensor.fake.h"
+#include "test_common.h"
+
+DEFINE_FFF_GLOBALS;
+
+int update_main( void );
+
+int main(void)
+{
+    
+   init_tests(); // will reset common and hook errors to asserts
+   
+   sensor_init_fake.return_val = true;
+   display_init_fake.return_val = true;
+   
+   update_main();
+   
+   assert( sensor_init_fake.call_count == 1 );
+   assert( display_init_fake.call_count == 1 );
+   assert( display_update_fake.call_count == 1 );
+   
+   printf("Test " __FILE__ " ok\n");
+   return 0;
+
+}
+ 

examples/weak_linking/test/sensor.fake.c

@@ -0,0 +1,12 @@
+
+
+#include "sensor.fake.h"
+DEFINE_FAKE_VALUE_FUNC( bool, sensor_init );
+DEFINE_FAKE_VALUE_FUNC( float, sensor_read );
+
+void TEST_sensor_generate_data( char* buffer, float value )
+{
+   buffer[0] = 0x10;
+   buffer[1] = (int)(value);
+   buffer[2] = (value - buffer[1])*255;
+}

examples/weak_linking/test/sensor.fake.h

@@ -0,0 +1,13 @@
+
+#ifndef _AUTOMOCK_SENSOR_H
+#define _AUTOMOCK_SENSOR_H
+
+#include "fff.h"
+#include "sensor.h"
+
+DECLARE_FAKE_VALUE_FUNC( bool, sensor_init );
+DECLARE_FAKE_VALUE_FUNC( float, sensor_read );
+
+void TEST_sensor_generate_data( char* buffer, float value );
+
+#endif // _AUTOMOCK_SENSOR_H

examples/weak_linking/test/sensor.test.c

@@ -0,0 +1,22 @@
+#include <stdio.h>
+#include "test_common.h"
+#include "sensor.h"
+#include "sensor.fake.h"
+
+DEFINE_FFF_GLOBALS;
+
+
+int main(void)
+{
+   init_tests(); 
+   
+   assert( sensor_init() == true );
+   
+
+   TEST_sensor_generate_data( GLOBAL_TEST_bus_read_ret, 1.5f );
+   float value = sensor_read();
+   float value_error = value - 1.5f;
+   assert( value_error < 0.1f && value_error > -0.1f );
+   printf("Test " __FILE__ " ok\n");
+   return 0;
+}

examples/weak_linking/test/test_common.c

@@ -0,0 +1,33 @@
+#include "test_common.h"
+#include <assert.h>
+#include <stdio.h>
+
+char GLOBAL_TEST_bus_read_ret[32];
+
+
+void spoof_runtime_error( const char* info )
+{
+    fprintf(stderr, "Runtime error: %s\n", info );
+    assert(0);
+}
+
+bool spoof_bus_read_write( uint8_t dev, uint8_t registry, uint8_t* buffer, int len, bool assume_echo )
+{
+    memcpy( buffer, GLOBAL_TEST_bus_read_ret, len );
+    fprintf(stderr, "bus spoof %d %d\n", (int)dev, (int)registry );
+    return true;
+}
+
+void init_tests()
+{
+    memset( GLOBAL_TEST_bus_read_ret, 0x00, sizeof(GLOBAL_TEST_bus_read_ret));
+    FFF_RESET_HISTORY();
+    
+    RESET_FAKE(bus_read_write);
+    RESET_FAKE(bus_write);
+    RESET_FAKE(runtime_error);
+    
+    runtime_error_fake.custom_fake = spoof_runtime_error;
+    bus_read_write_fake.custom_fake = spoof_bus_read_write;
+    bus_write_fake.return_val = true;
+}

examples/weak_linking/test/test_common.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <assert.h>
+#include <stdio.h>
+
+#include "fff.h"
+#include "bus.fake.h"
+#include "error.fake.h"
+
+
+void init_tests();
+
+extern char GLOBAL_TEST_bus_read_ret[32];