Support building under CYGWIN

- Parse CHANGES file with Universal Python line endings in case
  the source tree was checked out with Windows line endings.
- Use our own clone of strnlen_s which might not be available
  everywhere.

Fixes KhronosGroup#508

CHANGES

@@ -3,6 +3,8 @@ Revision history for SPIRV-Tools
 v2016.7-dev 2016-12-13
  - Add build target spirv-tools-vimsyntax to generate spvasm.vim, a SPIR-V
    assembly syntax file for Vim.
+ - Fixes:
+   #508: Support compilation under CYGWIN
 
 v2016.6 2016-12-13
  - Published the C++ interface for assembling, disassembling, validation, and

CMakeLists.txt

@@ -30,6 +30,8 @@ if("${CMAKE_SYSTEM_NAME}" STREQUAL "Linux")
   add_definitions(-DSPIRV_LINUX)
 elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "Windows")
   add_definitions(-DSPIRV_WINDOWS)
+elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "CYGWIN")
+  add_definitions(-DSPIRV_WINDOWS)
 elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "Darwin")
   add_definitions(-DSPIRV_MAC)
 elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "Android")

source/binary.cpp

@@ -550,7 +550,7 @@ spv_result_t Parser::parseOperand(size_t inst_offset,
       const size_t remaining_input_bytes =
           sizeof(uint32_t) * (_.num_words - _.word_index);
       const size_t string_num_content_bytes =
-          strnlen(string, remaining_input_bytes);
+          spv_strnlen_s(string, remaining_input_bytes);
       // If there was no terminating null byte, then that's an end-of-input
       // error.
       if (string_num_content_bytes == remaining_input_bytes)
@@ -770,3 +770,11 @@ void spvBinaryDestroy(spv_binary binary) {
   delete[] binary->code;
   delete binary;
 }
+
+size_t spv_strnlen_s(const char* str, size_t strsz) {
+  if (!str) return 0;
+  for (size_t i = 0; i < strsz; i++) {
+    if (!str[i]) return i;
+  }
+  return strsz;
+}

source/binary.h

@@ -27,4 +27,10 @@ spv_result_t spvBinaryHeaderGet(const spv_const_binary binary,
                                 const spv_endianness_t endian,
                                 spv_header_t* header);
 
+// Returns the number of non-null characters in str before the first null
+// character, or strsz if there is no null character.  Examines at most the
+// first strsz characters in str.  Returns 0 if str is nullptr.  This is a
+// replacement for C11's strnlen_s which might not exist in all environments.
+size_t spv_strnlen_s(const char* str, size_t strsz);
+
 #endif  // LIBSPIRV_BINARY_H_

test/CMakeLists.txt

@@ -71,6 +71,7 @@ set(TEST_SOURCES
   binary_endianness_test.cpp
   binary_header_get_test.cpp
   binary_parse_test.cpp
+  binary_strnlen_s_test.cpp
   binary_to_text_test.cpp
   binary_to_text.literal_test.cpp
   capability_set_test.cpp

test/binary_strnlen_s_test.cpp

@@ -0,0 +1,30 @@
+// Copyright (c) 2016 Google Inc.
+//
+// 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.
+
+#include "unit_spirv.h"
+
+namespace {
+
+TEST(Strnlen, Samples) {
+  EXPECT_EQ(0u, spv_strnlen_s(nullptr, 0));
+  EXPECT_EQ(0u, spv_strnlen_s(nullptr, 5));
+  EXPECT_EQ(0u, spv_strnlen_s("abc", 0));
+  EXPECT_EQ(1u, spv_strnlen_s("abc", 1));
+  EXPECT_EQ(3u, spv_strnlen_s("abc", 3));
+  EXPECT_EQ(3u, spv_strnlen_s("abc\0", 5));
+  EXPECT_EQ(0u, spv_strnlen_s("\0", 5));
+  EXPECT_EQ(1u, spv_strnlen_s("a\0c", 5));
+}
+
+}  // anonymous namespace

utils/update_build_version.py

@@ -78,7 +78,7 @@ def deduce_software_version(directory):
 
     pattern = re.compile(r'(v\d+\.\d+(-dev)?) \d\d\d\d-\d\d-\d\d$')
     changes_file = os.path.join(directory, 'CHANGES')
-    with open(changes_file) as f:
+    with open(changes_file, mode='rU') as f:
         for line in f.readlines():
             match = pattern.match(line)
             if match: