const sample container (#101)

* feat(sample_container): use const specifier
This will put the sample container in the flash, saving RAM.

* feat(generate_ocre_file): use const specifier
This will put the generated sample container in the flash,
saving RAM.

---------

Signed-off-by: Marco Casaroli <marco.casaroli@gmail.com>

Author: casaroli

CMakeLists.txt

@@ -65,7 +65,7 @@ if(NOT "${OCRE_INPUT_FILE}" STREQUAL "")
 
     add_custom_command(
         OUTPUT ${CMAKE_CURRENT_LIST_DIR}/src/ocre/ocre_input_file.g
-                COMMAND xxd -i ${OCRE_INPUT_FILE} | sed 's/unsigned char .*\\[/static const unsigned char wasm_binary[/' | sed 's/unsigned int .*_len/static const unsigned int wasm_binary_len/' > ${CMAKE_CURRENT_LIST_DIR}/src/ocre/ocre_input_file.g
+        COMMAND xxd -n wasm_binary -i ${OCRE_INPUT_FILE} | sed 's/^unsigned/static const unsigned/' > ${OCRE_ROOT_DIR}/src/ocre/ocre_input_file.g
         DEPENDS ${OCRE_INPUT_FILE}
         COMMENT "Generating C header from ${OCRE_INPUT_FILE}"
     )

src/ocre/ocre_input_file.h

@@ -8,7 +8,7 @@
 #ifndef OCRE_INPUT_FILE_H
 #define OCRE_INPUT_FILE_H
 // Sample WASM binary data
-static unsigned char wasm_binary[] = {
+static const unsigned char wasm_binary[] = {
             0x00, 0x61, 0x73, 0x6d, 0x01, 0x00, 0x00, 0x00, 0x01, 0x35, 0x09, 0x60,
         0x03, 0x7f, 0x7f, 0x7f, 0x01, 0x7f, 0x60, 0x03, 0x7f, 0x7e, 0x7f, 0x01,
         0x7e, 0x60, 0x01, 0x7f, 0x01, 0x7f, 0x60, 0x02, 0x7f, 0x7f, 0x01, 0x7f,
@@ -332,6 +332,6 @@ static unsigned char wasm_binary[] = {
         0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0x04, 0x00, 0x00
         };
 
-static unsigned int wasm_binary_len = 3850;
+static const unsigned int wasm_binary_len = 3850;
 
 #endif // OCRE_INPUT_FILE_H