Add documentation and minor style changes

Add doxygen style documentation to `mbedtls_test_fail`, `mbedtls_test_skip`,
`mbedtls_test_set_step` and `mbedtls_test_info_reset`. This should make it
easier to understand how the test infrastructure is used.

Also make some minor style changes to meet the coding standards and make it
more obvious that `mbedtls_test_info.step` was being incremented.

Signed-off-by: Chris Jones <christopher.jones@arm.com>

tests/include/test/helpers.h

@@ -70,19 +70,42 @@ extern mbedtls_test_info_t mbedtls_test_info;
 int mbedtls_test_platform_setup( void );
 void mbedtls_test_platform_teardown( void );
 
+/**
+ * \brief           Record the given, usually current, test as a failure.
+ *
+ * \param test      Name of the test to fail.
+ * \param line_no   Line number where the failure originated.
+ * \param filename  Filename where the failure originated.
+ */
 void mbedtls_test_fail( const char *test, int line_no, const char* filename );
+
+/**
+ * \brief           Record the given, usually current, test as skipped.
+ *
+ * \param test      Name of the test to skip.
+ * \param line_no   Line number where the test skipped.
+ * \param filename  Filename where the test skipped.
+ */
 void mbedtls_test_skip( const char *test, int line_no, const char* filename );
 
-/** Set the test step number for failure reports.
+/**
+ * \brief       Set the test step number for failure reports.
  *
- * Call this function to display "step NNN" in addition to the line number
+ * \note        Call this function to display "step NNN" in addition to the
- * and file name if a test fails. Typically the "step number" is the index
+ *              line number and file name if a test fails. Typically the "step
- * of a for loop but it can be whatever you want.
+ *              number" is the index of a for loop but it can be whatever you
+ *              want.
  *
  * \param step  The step number to report.
  */
 void mbedtls_test_set_step( unsigned long step );
 
+/**
+ * \brief       Reset mbedtls_test_info to a ready/starting state.
+ *
+ * \note        Clears the test, line_no, filename, step and result from any
+ *              previously stored values and initialises them ready to be used.
+ */
 void mbedtls_test_info_reset( void );
 
 /**

tests/suites/host_test.function

@@ -601,7 +601,7 @@ int execute_tests( int argc , const char ** argv )
     }
 
     /* Initialize the struct that holds information about the last test */
-    mbedtls_test_info_reset();
+    mbedtls_test_info_reset( );
 
     /* Now begin to execute the tests in the testfiles */
     for ( testfile_index = 0;
@@ -683,7 +683,7 @@ int execute_tests( int argc , const char ** argv )
             // If there are no unmet dependencies execute the test
             if( unmet_dep_count == 0 )
             {
-                mbedtls_test_info_reset();
+                mbedtls_test_info_reset( );
 
 #if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
                 /* Suppress all output from the library unless we're verbose

tests/suites/target_test.function

@@ -384,7 +384,7 @@ int execute_tests( int args, const char ** argv )
     while ( 1 )
     {
         ret = 0;
-        mbedtls_test_info_reset();
+        mbedtls_test_info_reset( );
         data_len = 0;
 
         data = receive_data( &data_len );

tests/suites/test_suite_asn1parse.function

@@ -594,6 +594,7 @@ void get_sequence_of( const data_t *input, int tag,
     unsigned char *p = input->x;
     const char *rest = description;
     unsigned long n;
+    unsigned int step = 0;
 
     TEST_EQUAL( mbedtls_asn1_get_sequence_of( &p, input->x + input->len,
                                               &head, tag ),
@@ -614,7 +615,7 @@ void get_sequence_of( const data_t *input, int tag,
             cur = &head;
             while( *rest )
             {
-                mbedtls_test_set_step( mbedtls_test_info.step + 1 );
+                mbedtls_test_set_step( step );
                 TEST_ASSERT( cur != NULL );
                 TEST_EQUAL( cur->buf.tag, tag );
                 n = strtoul( rest, (char **) &rest, 0 );
@@ -625,6 +626,7 @@ void get_sequence_of( const data_t *input, int tag,
                 if( *rest )
                     ++rest;
                 cur = cur->next;
+                ++step;
             }
             TEST_ASSERT( cur == NULL );
         }