Rename generate_code.py -> generate_test_code.py
diff --git a/tests/scripts/generate_test_code.py b/tests/scripts/generate_test_code.py
new file mode 100644
index 0000000..38b0d75
--- /dev/null
+++ b/tests/scripts/generate_test_code.py
@@ -0,0 +1,726 @@
+# Test suites code generator.
+#
+# Copyright (C) 2018, ARM Limited, All Rights Reserved
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# This file is part of mbed TLS (https://tls.mbed.org)
+
+"""
+Test Suite code generator.
+
+Generates a test source file using following input files:
+
+test_suite_xyz.function - Read test functions from test suite functions file.
+test_suite_xyz.data - Read test functions and their dependencies to generate
+                      dispatch and dependency check code.
+main template - Substitute generated test function dispatch code, dependency
+                checking code.
+platform .function - Read host or target platform implementation for
+                     dispatching test cases from .data file.
+helper .function - Read common reusable functions.
+"""
+
+
+import os
+import re
+import argparse
+import shutil
+
+
+BEGIN_HEADER_REGEX = '/\*\s*BEGIN_HEADER\s*\*/'
+END_HEADER_REGEX = '/\*\s*END_HEADER\s*\*/'
+
+BEGIN_SUITE_HELPERS_REGEX = '/\*\s*BEGIN_SUITE_HELPERS\s*\*/'
+END_SUITE_HELPERS_REGEX = '/\*\s*END_SUITE_HELPERS\s*\*/'
+
+BEGIN_DEP_REGEX = 'BEGIN_DEPENDENCIES'
+END_DEP_REGEX = 'END_DEPENDENCIES'
+
+BEGIN_CASE_REGEX = '/\*\s*BEGIN_CASE\s*(.*?)\s*\*/'
+END_CASE_REGEX = '/\*\s*END_CASE\s*\*/'
+
+
+class InvalidFileFormat(Exception):
+    """
+    Exception to indicate invalid file format. 
+    """
+    pass
+
+
+class FileWrapper(file):
+    """
+    File wrapper class. Provides reading with line no. tracking. 
+    """
+
+    def __init__(self, file_name):
+        """
+        Init file handle.
+        
+        :param file_name: File path to open.
+        """
+        super(FileWrapper, self).__init__(file_name, 'r')
+        self.line_no = 0
+
+    def next(self):
+        """
+        Iterator return impl.
+        :return: Line read from file.
+        """
+        line = super(FileWrapper, self).next()
+        if line:
+            self.line_no += 1
+        return line
+
+    def readline(self, limit=0):
+        """
+        Wrap the base class readline.
+        
+        :param limit: limit to match file.readline([limit])
+        :return: Line read from file.
+        """
+        return self.next()
+
+
+def split_dep(dep):
+    """
+    Split NOT character '!' from dependency. Used by gen_deps()
+
+    :param dep: Dependency list
+    :return: list of tuples where index 0 has '!' if there was a '!' before the dependency string
+    """
+    return ('!', dep[1:]) if dep[0] == '!' else ('', dep)
+
+
+def gen_deps(deps):
+    """
+    Generates dependency i.e. if def and endif code
+
+    :param deps: List of dependencies.
+    :return: if defined and endif code with macro annotations for readability.
+    """
+    dep_start = ''.join(['#if %sdefined(%s)\n' % split_dep(x) for x in deps])
+    dep_end = ''.join(['#endif /* %s */\n' % x for x in reversed(deps)])
+
+    return dep_start, dep_end
+
+
+def gen_deps_one_line(deps):
+    """
+    Generates dependency checks in one line. Useful for writing code in #else case.
+
+    :param deps: List of dependencies.
+    :return: ifdef code
+    """
+    defines = ('#if ' if len(deps) else '') + ' && '.join(['%sdefined(%s)' % split_dep(x) for x in deps])
+    return defines
+
+
+def gen_function_wrapper(name, locals, args_dispatch):
+    """
+    Creates test function wrapper code. A wrapper has the code to unpack parameters from parameters[] array.
+
+    :param name: Test function name
+    :param locals: Local variables declaration code
+    :param args_dispatch: List of dispatch arguments. Ex: ['(char *)params[0]', '*((int *)params[1])']
+    :return: Test function wrapper.
+    """
+    # Then create the wrapper
+    wrapper = '''
+void {name}_wrapper( void ** params )
+{{
+    {unused_params}
+{locals}
+    {name}( {args} );
+}}
+'''.format(name=name, unused_params='(void)params;' if len(args_dispatch) == 0 else '',
+           args=', '.join(args_dispatch),
+           locals=locals)
+    return wrapper
+
+
+def gen_dispatch(name, deps):
+    """
+    Generates dispatch code for the test function table.
+
+    :param name: Test function name
+    :param deps: List of dependencies
+    :return: Dispatch code.
+    """
+    if len(deps):
+        ifdef = gen_deps_one_line(deps)
+        dispatch_code = '''
+{ifdef}
+    {name}_wrapper,
+#else
+    NULL,
+#endif
+'''.format(ifdef=ifdef, name=name)
+    else:
+        dispatch_code = '''
+    {name}_wrapper,
+'''.format(name=name)
+
+    return dispatch_code
+
+
+def parse_until_pattern(funcs_f, end_regex):
+    """
+    Parses function headers or helper code until end pattern.
+    
+    :param funcs_f: file object for .functions file
+    :param end_regex: Pattern to stop parsing
+    :return: Test suite headers code
+    """
+    headers = '#line %d "%s"\n' % (funcs_f.line_no + 1, funcs_f.name)
+    for line in funcs_f:
+        if re.search(end_regex, line):
+            break
+        headers += line
+    else:
+        raise InvalidFileFormat("file: %s - end pattern [%s] not found!" % (funcs_f.name, end_regex))
+
+    return headers
+
+
+def parse_suite_deps(funcs_f):
+    """
+    Parses test suite dependencies.
+    
+    :param funcs_f: file object for .functions file
+    :return: List of test suite dependencies.
+    """
+    deps = []
+    for line in funcs_f:
+        m = re.search('depends_on\:(.*)', line.strip())
+        if m:
+            deps += [x.strip() for x in m.group(1).split(':')]
+        if re.search(END_DEP_REGEX, line):
+            break
+    else:
+        raise InvalidFileFormat("file: %s - end dependency pattern [%s] not found!" % (funcs_f.name, END_DEP_REGEX))
+
+    return deps
+
+
+def parse_function_deps(line):
+    """
+    Parses function dependencies.
+    
+    :param line: Line from .functions file that has dependencies.
+    :return: List of dependencies.
+    """
+    deps = []
+    m = re.search(BEGIN_CASE_REGEX, line)
+    dep_str = m.group(1)
+    if len(dep_str):
+        m = re.search('depends_on:(.*)', dep_str)
+        if m:
+            deps = [x.strip() for x in m.group(1).strip().split(':')]
+    return deps
+
+
+def parse_function_signature(line):
+    """
+    Parsing function signature
+    
+    :param line: Line from .functions file that has a function signature.
+    :return: function name, argument list, local variables for wrapper function and argument dispatch code.
+    """
+    args = []
+    locals = ''
+    args_dispatch = []
+    m = re.search('\s*void\s+(\w+)\s*\(', line, re.I)
+    if not m:
+        raise ValueError("Test function should return 'void'\n%s" % line)
+    name = m.group(1)
+    line = line[len(m.group(0)):]
+    arg_idx = 0
+    for arg in line[:line.find(')')].split(','):
+        arg = arg.strip()
+        if arg == '':
+            continue
+        if re.search('int\s+.*', arg.strip()):
+            args.append('int')
+            args_dispatch.append('*( (int *) params[%d] )' % arg_idx)
+        elif re.search('char\s*\*\s*.*', arg.strip()):
+            args.append('char*')
+            args_dispatch.append('(char *) params[%d]' % arg_idx)
+        elif re.search('HexParam_t\s*\*\s*.*', arg.strip()):
+            args.append('hex')
+            # create a structure
+            locals += """    HexParam_t hex%d = {%s, %s};
+""" % (arg_idx, '(uint8_t *) params[%d]' % arg_idx, '*( (uint32_t *) params[%d] )' % (arg_idx + 1))
+
+            args_dispatch.append('&hex%d' % arg_idx)
+            arg_idx += 1
+        else:
+            raise ValueError("Test function arguments can only be 'int', 'char *' or 'HexParam_t'\n%s" % line)
+        arg_idx += 1
+
+    return name, args, locals, args_dispatch
+
+
+def parse_function_code(funcs_f, deps, suite_deps):
+    """
+    Parses out a function from function file object and generates function and dispatch code.
+    
+    :param funcs_f: file object of the functions file.
+    :param deps: List of dependencies
+    :param suite_deps: List of test suite dependencies
+    :return: Function name, arguments, function code and dispatch code.
+    """
+    code = '#line %d "%s"\n' % (funcs_f.line_no + 1, funcs_f.name)
+    for line in funcs_f:
+        # Check function signature
+        m = re.match('.*?\s+(\w+)\s*\(', line, re.I)
+        if m:
+            # check if we have full signature i.e. split in more lines
+            if not re.match('.*\)', line):
+                for lin in funcs_f:
+                    line += lin
+                    if re.search('.*?\)', line):
+                        break
+            name, args, locals, args_dispatch = parse_function_signature(line)
+            code += line.replace(name, 'test_' + name)
+            name = 'test_' + name
+            break
+    else:
+        raise InvalidFileFormat("file: %s - Test functions not found!" % funcs_f.name)
+
+    for line in funcs_f:
+        if re.search(END_CASE_REGEX, line):
+            break
+        code += line
+    else:
+        raise InvalidFileFormat("file: %s - end case pattern [%s] not found!" % (funcs_f.name, END_CASE_REGEX))
+
+    # Add exit label if not present
+    if code.find('exit:') == -1:
+        s = code.rsplit('}', 1)
+        if len(s) == 2:
+            code = """exit:
+    ;;
+}""".join(s)
+
+    code += gen_function_wrapper(name, locals, args_dispatch)
+    ifdef, endif = gen_deps(deps)
+    dispatch_code = gen_dispatch(name, suite_deps + deps)
+    return name, args, ifdef + code + endif, dispatch_code
+
+
+def parse_functions(funcs_f):
+    """
+    Returns functions code pieces
+    
+    :param funcs_f: file object of the functions file.
+    :return: List of test suite dependencies, test function dispatch code, function code and
+             a dict with function identifiers and arguments info.
+    """
+    suite_headers = ''
+    suite_helpers = ''
+    suite_deps = []
+    suite_functions = ''
+    func_info = {}
+    function_idx = 0
+    dispatch_code = ''
+    for line in funcs_f:
+        if re.search(BEGIN_HEADER_REGEX, line):
+            headers = parse_until_pattern(funcs_f, END_HEADER_REGEX)
+            suite_headers += headers
+        elif re.search(BEGIN_SUITE_HELPERS_REGEX, line):
+            helpers = parse_until_pattern(funcs_f, END_SUITE_HELPERS_REGEX)
+            suite_helpers += helpers
+        elif re.search(BEGIN_DEP_REGEX, line):
+            deps = parse_suite_deps(funcs_f)
+            suite_deps += deps
+        elif re.search(BEGIN_CASE_REGEX, line):
+            deps = parse_function_deps(line)
+            func_name, args, func_code, func_dispatch = parse_function_code(funcs_f, deps, suite_deps)
+            suite_functions += func_code
+            # Generate dispatch code and enumeration info
+            assert func_name not in func_info, "file: %s - function %s re-declared at line %d" % \
+                                               (funcs_f.name, func_name, funcs_f.line_no)
+            func_info[func_name] = (function_idx, args)
+            dispatch_code += '/* Function Id: %d */\n' % function_idx
+            dispatch_code += func_dispatch
+            function_idx += 1
+
+    ifdef, endif = gen_deps(suite_deps)
+    func_code = ifdef + suite_headers + suite_helpers + suite_functions + endif
+    return suite_deps, dispatch_code, func_code, func_info
+
+
+def escaped_split(str, ch):
+    """
+    Split str on character ch but ignore escaped \{ch}
+    Since return value is used to write back to the intermediate data file. 
+    Any escape characters in the input are retained in the output.
+
+    :param str: String to split
+    :param ch: split character
+    :return: List of splits
+    """
+    if len(ch) > 1:
+        raise ValueError('Expected split character. Found string!')
+    out = []
+    part = ''
+    escape = False
+    for i in range(len(str)):
+        if not escape and str[i] == ch:
+            out.append(part)
+            part = ''
+        else:
+            part += str[i]
+            escape = not escape and str[i] == '\\'
+    if len(part):
+        out.append(part)
+    return out
+
+
+def parse_test_data(data_f, debug=False):
+    """
+    Parses .data file
+    
+    :param data_f: file object of the data file.
+    :return: Generator that yields test name, function name, dependency list and function argument list.
+    """
+    STATE_READ_NAME = 0
+    STATE_READ_ARGS = 1
+    state = STATE_READ_NAME
+    deps = []
+    name = ''
+    for line in data_f:
+        line = line.strip()
+        if len(line) and line[0] == '#': # Skip comments
+            continue
+
+        # Blank line indicates end of test
+        if len(line) == 0:
+            assert state != STATE_READ_ARGS, "Newline before arguments. " \
+                                                 "Test function and arguments missing for %s" % name
+            continue
+
+        if state == STATE_READ_NAME:
+            # Read test name
+            name = line
+            state = STATE_READ_ARGS
+        elif state == STATE_READ_ARGS:
+            # Check dependencies
+            m = re.search('depends_on\:(.*)', line)
+            if m:
+                deps = [x.strip() for x in m.group(1).split(':') if len(x.strip())]
+            else:
+                # Read test vectors
+                parts = escaped_split(line, ':')
+                function = parts[0]
+                args = parts[1:]
+                yield name, function, deps, args
+                deps = []
+                state = STATE_READ_NAME
+    assert state != STATE_READ_ARGS, "Newline before arguments. " \
+                                     "Test function and arguments missing for %s" % name
+
+
+def gen_dep_check(dep_id, dep):
+    """
+    Generate code for the dependency.
+    
+    :param dep_id: Dependency identifier
+    :param dep: Dependency macro
+    :return: Dependency check code
+    """
+    assert dep_id > -1, "Dependency Id should be a positive integer."
+    noT, dep = ('!', dep[1:]) if dep[0] == '!' else ('', dep)
+    assert len(dep) > 0, "Dependency should not be an empty string."
+    dep_check = '''
+        case {id}:
+            {{
+#if {noT}defined({macro})
+                ret = DEPENDENCY_SUPPORTED;
+#else
+                ret = DEPENDENCY_NOT_SUPPORTED;
+#endif
+            }}
+            break;'''.format(noT=noT, macro=dep, id=dep_id)
+    return dep_check
+
+
+def gen_expression_check(exp_id, exp):
+    """
+    Generates code for expression check
+    
+    :param exp_id: Expression Identifier
+    :param exp: Expression/Macro
+    :return: Expression check code
+    """
+    assert exp_id > -1, "Expression Id should be a positive integer."
+    assert len(exp) > 0, "Expression should not be an empty string."
+    exp_code = '''
+        case {exp_id}:
+            {{
+                *out_value = {expression};
+            }}
+            break;'''.format(exp_id=exp_id, expression=exp)
+    return exp_code
+
+
+def write_deps(out_data_f, test_deps, unique_deps):
+    """
+    Write dependencies to intermediate test data file.
+    It also returns dependency check code.
+      
+    :param out_data_f: Output intermediate data file
+    :param test_deps: Dependencies
+    :param unique_deps: Mutable list to track unique dependencies that are global to this re-entrant function.
+    :return: returns dependency check code.
+    """
+    dep_check_code = ''
+    if len(test_deps):
+        out_data_f.write('depends_on')
+        for dep in test_deps:
+            if dep not in unique_deps:
+                unique_deps.append(dep)
+                dep_id = unique_deps.index(dep)
+                dep_check_code += gen_dep_check(dep_id, dep)
+            else:
+                dep_id = unique_deps.index(dep)
+            out_data_f.write(':' + str(dep_id))
+        out_data_f.write('\n')
+    return dep_check_code
+
+
+def write_parameters(out_data_f, test_args, func_args, unique_expressions):
+    """
+    Writes test parameters to the intermediate data file.
+    Also generates expression code.
+     
+    :param out_data_f: Output intermediate data file
+    :param test_args: Test parameters
+    :param func_args: Function arguments
+    :param unique_expressions: Mutable list to track unique expressions that are global to this re-entrant function.
+    :return: Returns expression check code.
+    """
+    expression_code = ''
+    for i in xrange(len(test_args)):
+        typ = func_args[i]
+        val = test_args[i]
+
+        # check if val is a non literal int val
+        if typ == 'int' and not re.match('(\d+$)|((0x)?[0-9a-fA-F]+$)', val):  # its an expression
+            typ = 'exp'
+            if val not in unique_expressions:
+                unique_expressions.append(val)
+                # exp_id can be derived from len(). But for readability and consistency with case of existing let's
+                # use index().
+                exp_id = unique_expressions.index(val)
+                expression_code += gen_expression_check(exp_id, val)
+                val = exp_id
+            else:
+                val = unique_expressions.index(val)
+        out_data_f.write(':' + typ + ':' + str(val))
+    out_data_f.write('\n')
+    return expression_code
+
+
+def gen_suite_deps_checks(suite_deps, dep_check_code, expression_code):
+    """
+    Adds preprocessor checks for test suite dependencies.
+    
+    :param suite_deps: Test suite dependencies read from the .functions file.
+    :param dep_check_code: Dependency check code
+    :param expression_code: Expression check code
+    :return: Dependency and expression code guarded by test suite dependencies.
+    """
+    if len(suite_deps):
+        ifdef = gen_deps_one_line(suite_deps)
+        dep_check_code = '''
+{ifdef}
+{code}
+#endif
+'''.format(ifdef=ifdef, code=dep_check_code)
+        expression_code = '''
+{ifdef}
+{code}
+#endif
+'''.format(ifdef=ifdef, code=expression_code)
+    return dep_check_code, expression_code
+
+
+def gen_from_test_data(data_f, out_data_f, func_info, suite_deps):
+    """
+    Generates dependency checks, expression code and intermediate data file from test data file.
+    
+    :param data_f: Data file object
+    :param out_data_f:Output intermediate data file
+    :param func_info: Dict keyed by function and with function id and arguments info
+    :param suite_deps: Test suite deps
+    :return: Returns dependency and expression check code
+    """
+    unique_deps = []
+    unique_expressions = []
+    dep_check_code = ''
+    expression_code = ''
+    for test_name, function_name, test_deps, test_args in parse_test_data(data_f):
+        out_data_f.write(test_name + '\n')
+
+        # Write deps
+        dep_check_code += write_deps(out_data_f, test_deps, unique_deps)
+
+        # Write test function name
+        test_function_name = 'test_' + function_name
+        assert test_function_name in func_info, "Function %s not found!" % test_function_name
+        func_id, func_args = func_info[test_function_name]
+        out_data_f.write(str(func_id))
+
+        # Write parameters
+        assert len(test_args) == len(func_args), \
+            "Invalid number of arguments in test %s. See function %s signature." % (test_name, function_name)
+        expression_code += write_parameters(out_data_f, test_args, func_args, unique_expressions)
+
+        # Write a newline as test case separator
+        out_data_f.write('\n')
+
+    dep_check_code, expression_code = gen_suite_deps_checks(suite_deps, dep_check_code, expression_code)
+    return dep_check_code, expression_code
+
+
+def generate_code(funcs_file, data_file, template_file, platform_file, help_file, suites_dir, c_file, out_data_file):
+    """
+    Generate mbed-os test code.
+
+    :param funcs_file: Functions file object
+    :param data_file: Data file object
+    :param template_file: Template file object
+    :param platform_file: Platform file object
+    :param help_file: Helper functions file object
+    :param suites_dir: Test suites dir
+    :param c_file: Output C file object
+    :param out_data_file: Output intermediate data file object
+    :return:
+    """
+    for name, path in [('Functions file', funcs_file),
+                       ('Data file', data_file),
+                       ('Template file', template_file),
+                       ('Platform file', platform_file),
+                       ('Help code file', help_file),
+                       ('Suites dir', suites_dir)]:
+        if not os.path.exists(path):
+            raise IOError("ERROR: %s [%s] not found!" % (name, path))
+
+    snippets = {'generator_script' : os.path.basename(__file__)}
+
+    # Read helpers
+    with open(help_file, 'r') as help_f, open(platform_file, 'r') as platform_f:
+        snippets['test_common_helper_file'] = help_file
+        snippets['test_common_helpers'] = help_f.read()
+        snippets['test_platform_file'] = platform_file
+        snippets['platform_code'] = platform_f.read().replace('DATA_FILE',
+                                                              out_data_file.replace('\\', '\\\\')) # escape '\'
+
+    # Function code
+    with FileWrapper(funcs_file) as funcs_f, open(data_file, 'r') as data_f, open(out_data_file, 'w') as out_data_f:
+        suite_deps, dispatch_code, func_code, func_info = parse_functions(funcs_f)
+        snippets['functions_code'] = func_code
+        snippets['dispatch_code'] = dispatch_code
+        dep_check_code, expression_code = gen_from_test_data(data_f, out_data_f, func_info, suite_deps)
+        snippets['dep_check_code'] = dep_check_code
+        snippets['expression_code'] = expression_code
+
+    snippets['test_file'] = c_file
+    snippets['test_main_file'] = template_file
+    snippets['test_case_file'] = funcs_file
+    snippets['test_case_data_file'] = data_file
+    # Read Template
+    # Add functions
+    #
+    with open(template_file, 'r') as template_f, open(c_file, 'w') as c_f:
+        line_no = 1
+        for line in template_f.readlines():
+            snippets['line_no'] = line_no + 1 # Increment as it sets next line number
+            code = line.format(**snippets)
+            c_f.write(code)
+            line_no += 1
+
+
+def check_cmd():
+    """
+    Command line parser.
+
+    :return:
+    """
+    parser = argparse.ArgumentParser(description='Generate code for mbed-os tests.')
+
+    parser.add_argument("-f", "--functions-file",
+                        dest="funcs_file",
+                        help="Functions file",
+                        metavar="FUNCTIONS",
+                        required=True)
+
+    parser.add_argument("-d", "--data-file",
+                        dest="data_file",
+                        help="Data file",
+                        metavar="DATA",
+                        required=True)
+
+    parser.add_argument("-t", "--template-file",
+                        dest="template_file",
+                        help="Template file",
+                        metavar="TEMPLATE",
+                        required=True)
+
+    parser.add_argument("-s", "--suites-dir",
+                        dest="suites_dir",
+                        help="Suites dir",
+                        metavar="SUITES",
+                        required=True)
+
+    parser.add_argument("--help-file",
+                        dest="help_file",
+                        help="Help file",
+                        metavar="HELPER",
+                        required=True)
+
+    parser.add_argument("-p", "--platform-file",
+                        dest="platform_file",
+                        help="Platform code file",
+                        metavar="PLATFORM_FILE",
+                        required=True)
+
+    parser.add_argument("-o", "--out-dir",
+                        dest="out_dir",
+                        help="Dir where generated code and scripts are copied",
+                        metavar="OUT_DIR",
+                        required=True)
+
+    args = parser.parse_args()
+
+    data_file_name = os.path.basename(args.data_file)
+    data_name = os.path.splitext(data_file_name)[0]
+
+    out_c_file = os.path.join(args.out_dir, data_name + '.c')
+    out_data_file = os.path.join(args.out_dir, data_file_name)
+
+    out_c_file_dir = os.path.dirname(out_c_file)
+    out_data_file_dir = os.path.dirname(out_data_file)
+    for d in [out_c_file_dir, out_data_file_dir]:
+        if not os.path.exists(d):
+            os.makedirs(d)
+
+    generate_code(args.funcs_file, args.data_file, args.template_file, args.platform_file,
+                  args.help_file, args.suites_dir, out_c_file, out_data_file)
+
+
+if __name__ == "__main__":
+    check_cmd()