minor code improvements; check the log below

[kmilo17pet]

gcc -Wall -flto -Wextra -Wimplicit-fallthrough=0 -Wformat-security -Wduplicated-cond -Wfloat-equal -Wshadow -Wconversion -Wsign-conversion -Wjump-misses-init -Wlogical-not-parentheses -Wnull-dereference -Wnull-dereference -Wstringop-overflow -fprofile-arcs -ftest-coverage -fstrict-aliasing -O2 -std=c89 -pedantic -D_POSIX_C_SOURCE=199309L -MD -Wstrict-aliasing -I. -I./src/Sigfox/ -I./src/main/ -I./src/test/ -c src/Sigfox/wssfm1xrx.c -o obj/src/Sigfox/wssfm1xrx.o
Compiling obj/src/Sigfox/wssfm1xrx.o [WARNING]
In file included from src/Sigfox/wssfm1xrx.c:19:0:
src/Sigfox/wssfm1xrx.h:177:16: warning: comma at end of enumerator list [-Wpedantic]
WSSFM1XRX_RCZ6,
^
src/Sigfox/wssfm1xrx.c: In function ‘WSSFM1XRX_AskChannels’:
src/Sigfox/wssfm1xrx.c:368:18: warning: conversion to ‘uint8_t {aka unsigned char}’ from ‘int’ may alter its value [-Wconversion]
Channels->x = (uint8_t)obj->RxFrame[0]- (uint8_t)'0';/* ((rspPtr-1))-(uint8_t)'0';/ /non compliant misra c 18.4/
^
src/Sigfox/wssfm1xrx.c:369:18: warning: conversion to ‘uint8_t {aka unsigned char}’ from ‘int’ may alter its value [-Wconversion]
Channels->y = (uint8_t)obj->RxFrame[2] -(uint8_t)'0' ; /* ((rspPtr+1))-(uint8_t)'0'; /
^
src/Sigfox/wssfm1xrx.c: In function ‘WSSFM1XRX_SendMessage’:
src/Sigfox/wssfm1xrx.c:505:17: warning: conversion to ‘uint8_t {aka unsigned char}’ from ‘int’ may alter its value [-Wconversion]
uint8_t slen = ((uint8_t)2size) + (uint8_t)6; /misra c 10.4 & 12.1/
^
src/Sigfox/wssfm1xrx.c: In function ‘DL_DiscriminateDownLink’:
src/Sigfox/wssfm1xrx.c:629:2: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
uint8_t i;
^~~~~~~
src/Sigfox/wssfm1xrx.c:635:16: warning: conversion to ‘uint8_t {aka unsigned char}’ from ‘int’ may alter its value [-Wconversion]
byteIndex += (uint8_t)WSSFM1XRX_DL_BYTES_OFFSET;
^
src/Sigfox/wssfm1xrx.c: In function ‘WSSFM1XRX_BuildFrame’:
src/Sigfox/wssfm1xrx.c:677:14: warning: conversion to ‘uint8_t {aka unsigned char}’ from ‘int’ may alter its value [-Wconversion]
finalsize = sizecopy((uint8_t)2);
^~~~~~~~
src/Sigfox/wssfm1xrx.c:680:10: warning: conversion to ‘int8_t {aka signed char}’ from ‘int’ may alter its value [-Wconversion]
for(i = ((int8_t)sizecopy-1) ; i >= 0; i--){ /*misra 10.4 */
^
src/Sigfox/wssfm1xrx.c: In function ‘NibbletoX’:
src/Sigfox/wssfm1xrx.c:704:8: warning: conversion to ‘uint8_t {aka unsigned char}’ from ‘int’ may alter its value [-Wconversion]
c_h = (value & (uint8_t)0x0Fu) + (uint8_t)'0' ;
^
src/Sigfox/wssfm1xrx.c:706:36: warning: conversion to ‘char’ from ‘int’ may alter its value [-Wconversion]
return (ch > (char)'9')? (ch + 7) : ch;