Refactor and generalize run_c
Generalize the very ad hoc run_c function into a function to generate
a C program to print the value of a list of expressions. Refactor the
code into several functions to make it more manageable.
No intended behavior change.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/scripts/test_psa_constant_names.py b/tests/scripts/test_psa_constant_names.py
index c7011a7..68bfe77 100755
--- a/tests/scripts/test_psa_constant_names.py
+++ b/tests/scripts/test_psa_constant_names.py
@@ -313,40 +313,97 @@
except OSError:
pass
-def run_c(type_word, expressions, include_path=None, keep_c=False):
- """Generate and run a program to print out numerical values for expressions."""
- if include_path is None:
- include_path = []
- if type_word == 'status':
- cast_to = 'long'
- printf_format = '%ld'
- else:
- cast_to = 'unsigned long'
- printf_format = '0x%08lx'
- c_name = None
- exe_name = None
- try:
- c_fd, c_name = tempfile.mkstemp(prefix='tmp-{}-'.format(type_word),
- suffix='.c',
- dir='programs/psa')
- exe_suffix = '.exe' if platform.system() == 'Windows' else ''
- exe_name = c_name[:-2] + exe_suffix
- remove_file_if_exists(exe_name)
- c_file = os.fdopen(c_fd, 'w', encoding='ascii')
- c_file.write('/* Generated by test_psa_constant_names.py for {} values */'
- .format(type_word))
- c_file.write('''
+def create_c_file(file_label):
+ """Create a temporary C file.
+
+ * ``file_label``: a string that will be included in the file name.
+
+ Return ```(c_file, c_name, exe_name)``` where ``c_file`` is a Python
+ stream open for writing to the file, ``c_name`` is the name of the file
+ and ``exe_name`` is the name of the executable that will be produced
+ by compiling the file.
+ """
+ c_fd, c_name = tempfile.mkstemp(prefix='tmp-{}-'.format(file_label),
+ suffix='.c')
+ exe_suffix = '.exe' if platform.system() == 'Windows' else ''
+ exe_name = c_name[:-2] + exe_suffix
+ remove_file_if_exists(exe_name)
+ c_file = os.fdopen(c_fd, 'w', encoding='ascii')
+ return c_file, c_name, exe_name
+
+def generate_c_printf_expressions(c_file, cast_to, printf_format, expressions):
+ """Generate C instructions to print the value of ``expressions``.
+
+ Write the code with ``c_file``'s ``write`` method.
+
+ Each expression is cast to the type ``cast_to`` and printed with the
+ printf format ``printf_format``.
+ """
+ for expr in expressions:
+ c_file.write(' printf("{}\\n", ({}) {});\n'
+ .format(printf_format, cast_to, expr))
+
+def generate_c_file(c_file,
+ caller, header,
+ main_generator):
+ """Generate a temporary C source file.
+
+ * ``c_file`` is an open stream on the C source file.
+ * ``caller``: an informational string written in a comment at the top
+ of the file.
+ * ``header``: extra code to insert before any function in the generated
+ C file.
+ * ``main_generator``: a function called with ``c_file`` as its sole argument
+ to generate the body of the ``main()`` function.
+ """
+ c_file.write('/* Generated by {} */'
+ .format(caller))
+ c_file.write('''
#include <stdio.h>
-#include <psa/crypto.h>
+''')
+ c_file.write(header)
+ c_file.write('''
int main(void)
{
''')
- for expr in expressions:
- c_file.write(' printf("{}\\n", ({}) {});\n'
- .format(printf_format, cast_to, expr))
- c_file.write(''' return 0;
+ main_generator(c_file)
+ c_file.write(''' return 0;
}
''')
+
+def get_c_expression_values(
+ cast_to, printf_format,
+ expressions,
+ caller=__name__, file_label='',
+ header='', include_path=None,
+ keep_c=False,
+): # pylint: disable=too-many-arguments
+ """Generate and run a program to print out numerical values for expressions.
+
+ * ``cast_to``: a C type.
+ * ``printf_format``: a printf format suitable for the type ``cast_to``.
+ * ``header``: extra code to insert before any function in the generated
+ C file.
+ * ``expressions``: a list of C language expressions that have the type
+ ``type``.
+ * ``include_path``: a list of directories containing header files.
+ * ``keep_c``: if true, keep the temporary C file (presumably for debugging
+ purposes).
+
+ Return the list of values of the ``expressions``.
+ """
+ if include_path is None:
+ include_path = []
+ c_name = None
+ exe_name = None
+ try:
+ c_file, c_name, exe_name = create_c_file(file_label)
+ generate_c_file(
+ c_file, caller, header,
+ lambda c_file: generate_c_printf_expressions(c_file,
+ cast_to, printf_format,
+ expressions)
+ )
c_file.close()
cc = os.getenv('CC', 'cc')
subprocess.check_call([cc] +
@@ -354,7 +411,7 @@
['-o', exe_name, c_name])
if keep_c:
sys.stderr.write('List of {} tests kept at {}\n'
- .format(type_word, c_name))
+ .format(caller, c_name))
else:
os.remove(c_name)
output = subprocess.check_output([exe_name])
@@ -362,6 +419,24 @@
finally:
remove_file_if_exists(exe_name)
+def run_c(type_word, expressions, include_path=None, keep_c=False):
+ """Generate and run a program to print out numerical values for expressions."""
+ if type_word == 'status':
+ cast_to = 'long'
+ printf_format = '%ld'
+ else:
+ cast_to = 'unsigned long'
+ printf_format = '0x%08lx'
+ return get_c_expression_values(
+ cast_to, printf_format,
+ expressions,
+ caller='test_psa_constant_names.py for {} values'.format(type_word),
+ file_label=type_word,
+ header='#include <psa/crypto.h>',
+ include_path=include_path,
+ keep_c=keep_c
+ )
+
NORMALIZE_STRIP_RE = re.compile(r'\s+')
def normalize(expr):
"""Normalize the C expression so as not to care about trivial differences.