Fix MISRA C 2012 deviations (#92)

* Fix MISRA deviations

* Not to apply operators to an expression of pointer type

* Not to use reserved identifier on internal variable

* Fix CI build flow

* Fix spelling

* Fix more rule 18.4 deviations

* Rename internal variable

* Not using negative index in implementation

* Fix more rule 18.4 deviations

* Update format

* Update CMakeLists.txt

* Update MISRA comments

* Use parentheses to specify operator order

* Fix typo

* Use negative index in the implementation

* Add assertion to ensure pBufCur points to the same array

---------

Co-authored-by: Ubuntu <[email protected]>

.github/.cSpellWords.txt

@@ -25,8 +25,9 @@ decihours
 Decihours
 DECIHOURS
 DNDEBUG
-DUNITY
 DSIGV
+DUNITY
+DUNITTEST
 Ecjuve
 EKHX
 getpacketid

.github/workflows/ci.yml

@@ -34,7 +34,7 @@ jobs:
           cmake -S test -B build/ \
           -G "Unix Makefiles" \
           -DCMAKE_BUILD_TYPE=Debug \
-          -DBUILD_UNIT_TESTS=ON \
+          -DUNITTEST=ON \
           -DCMAKE_C_FLAGS='--coverage -Wall -Wextra -DNDEBUG -DLOGGING_LEVEL_DEBUG=1'
           make -C build/ all
 

MISRA.md

@@ -21,3 +21,13 @@ _Ref 5.4.1_
         in use and changing the name will break existing user projects. Thus, for
         backwards compatibility, the macro is not modified and kept as is and the
         deviation is suppressed.
+
+_Ref 18.2.1_
+
+- MISRA Rule 18.2 states that two pointers may only be subtracted if they point
+        to elements of the same array. In this library, array of bytes are used to process
+        data. Functions which fill the arrays with data update an index to an offset.
+        To know the amount of data added to the array, the beginning address of the array has
+        to be subtracted from the index. It is manually verified that the index will always be
+        within bounds of the array. However, Coverity is flagging this as a deviation. Thus, we
+        are suppressing it.

README.md

@@ -85,7 +85,7 @@ include paths required to build this library.
 
 1. Go to the root directory of this repository.
 
-1. Run the _cmake_ command: `cmake -S test -B build -DBUILD_UNIT_TESTS=ON`.
+1. Run the _cmake_ command: `cmake -S test -B build -DUNITTEST=ON`.
 
 1. Run this command to build the library and unit tests: `make -C build all`.
 

source/include/sigv4_internal.h

@@ -155,12 +155,12 @@
  */
 typedef struct SigV4DateTime
 {
-    int32_t tm_year; /**< Year (1900 or later) */
-    int32_t tm_mon;  /**< Month (1 to 12) */
-    int32_t tm_mday; /**< Day of Month (1 to 28/29/30/31) */
-    int32_t tm_hour; /**< Hour (0 to 23) */
-    int32_t tm_min;  /**< Minutes (0 to 59) */
-    int32_t tm_sec;  /**< Seconds (0 to 60) */
+    int32_t year; /**< Year (1900 or later) */
+    int32_t mon;  /**< Month (1 to 12) */
+    int32_t mday; /**< Day of Month (1 to 28/29/30/31) */
+    int32_t hour; /**< Hour (0 to 23) */
+    int32_t min;  /**< Minutes (0 to 59) */
+    int32_t sec;  /**< Seconds (0 to 60) */
 } SigV4DateTime_t;
 
 /**