Add compiler warning check in the CI workflow (#177)

* Add compiler warning check in the CI workflow and fix compiler warning in the implementation

---------

Co-authored-by: ActoryOu <jay2002824@gmail.com>

Author: chinglee-iot

.github/.cSpellWords.txt

@@ -49,4 +49,9 @@ utest
 vect
 Vect
 VECT
+Wconversion
+Werror
+Weverything
+Wextra
+Wpedantic
 Wunused

.github/workflows/ci.yml

@@ -16,10 +16,15 @@ jobs:
       - name: Build
         run: |
           sudo apt-get install -y lcov
+
+          # Build the coverity analysis project as well to check compiler warning.
+          # Coverity analysis project builds coreHTTP source file only. llhttp source
+          # files are not built in this target.
           cmake -S test -B build/ \
           -G "Unix Makefiles" \
           -DCMAKE_BUILD_TYPE=Debug \
           -DUNITTEST=1 \
+          -DCOV_ANALYSIS=1 \
           -DCMAKE_C_FLAGS='--coverage -Wall -Wextra -DNDEBUG'
           make -C build/ all
 

source/core_http_client.c

@@ -545,12 +545,12 @@ static int8_t caseInsensitiveStringCmp( const char * str1,
         /* Subtract offset to go from lowercase to uppercase ASCII character */
         if( ( firstChar >= 'a' ) && ( firstChar <= 'z' ) )
         {
-            firstChar = firstChar - offset;
+            firstChar = ( char ) ( firstChar - offset );
         }
 
         if( ( secondChar >= 'a' ) && ( secondChar <= 'z' ) )
         {
-            secondChar = secondChar - offset;
+            secondChar = ( char ) ( secondChar - offset );
         }
 
         if( ( firstChar ) != ( secondChar ) )
@@ -1249,6 +1249,7 @@ static uint8_t convertInt32ToAscii( int32_t value,
     uint8_t numOfDigits = 0U;
     uint8_t index = 0U;
     uint8_t isNegative = 0U;
+    int32_t bufferIndex;
     char temp = '\0';
 
     assert( pBuffer != NULL );
@@ -1263,7 +1264,7 @@ static uint8_t convertInt32ToAscii( int32_t value,
         *pBuffer = '-';
 
         /* Convert the value to its absolute representation. */
-        absoluteValue = value * -1;
+        absoluteValue = value * ( -1 );
     }
 
     /* Write the absolute integer value in reverse ASCII representation. */
@@ -1279,11 +1280,12 @@ static uint8_t convertInt32ToAscii( int32_t value,
     for( index = 0U; index < ( numOfDigits / 2U ); index++ )
     {
         temp = pBuffer[ isNegative + index ];
-        pBuffer[ isNegative + index ] = pBuffer[ isNegative + numOfDigits - index - 1U ];
-        pBuffer[ isNegative + numOfDigits - index - 1U ] = temp;
+        bufferIndex = ( int32_t ) isNegative + ( int32_t ) numOfDigits - ( int32_t ) index - 1;
+        pBuffer[ isNegative + index ] = pBuffer[ bufferIndex ];
+        pBuffer[ bufferIndex ] = temp;
     }
 
-    return( isNegative + numOfDigits );
+    return ( uint8_t ) ( isNegative + numOfDigits );
 }
 
 /*-----------------------------------------------------------*/

test/CMakeLists.txt

@@ -44,16 +44,25 @@ if( COV_ANALYSIS )
 
     # Target for Coverity analysis that builds the library.
     add_library( coverity_analysis
-                ${HTTP_SOURCES} )
+                 ${CMAKE_CURRENT_LIST_DIR}/../source/core_http_client.c )
 
     # Build HTTP library target without custom config dependency.
     target_compile_definitions( coverity_analysis PUBLIC HTTP_DO_NOT_USE_CUSTOM_CONFIG=1 )
 
     # HTTP public include path.
     target_include_directories( coverity_analysis PUBLIC ${HTTP_INCLUDE_PUBLIC_DIRS} )
 
-    # Build HTTP library target without logging
-    target_compile_options(coverity_analysis PUBLIC -DNDEBUG )
+    target_compile_options( coverity_analysis PUBLIC
+        # Build HTTP library target without logging
+        -DNDEBUG
+
+        # GCC compiler option
+        -Wall
+        -Wextra
+        -Wpedantic
+        -Wconversion
+        -Werror
+    )
 endif()
 # ===================== Clone needed third-party libraries ======================