1# Copyright (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
2#
3# This program is free software; you can redistribute it and/or modify
4# it under the terms of the GNU General Public License as published by
5# the Free Software Foundation; version 2 of the License.
6#
7# This program is distributed in the hope that it will be useful,
8# but WITHOUT ANY WARRANTY; without even the implied warranty of
9# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10# GNU General Public License for more details.
11#
12# You should have received a copy of the GNU General Public License
13# along with this program; if not, write to the Free Software
14# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1335  USA
15
16#
17# Rules for checking that the abi/api has not changed.
18#
19# The following steps are followed in the do_abi_check rule below
20#
21# 1) Generate preprocessor output for the files that need to
22#    be tested for abi/api changes. use -nostdinc to prevent
23#    generation of preprocessor output for system headers. This
24#    results in messages in stderr saying that these headers
25#    were not found. Redirect the stderr output to /dev/null
26#    to prevent seeing these messages.
27# 2) sed the output to
28#    2.1) remove blank lines and lines that begin with "# "
29#    2.2) When gcc -E is run on the Mac OS  and solaris sparc platforms it
30#         introduces a line of output that shows up as a difference between
31#         the .pp and .out files. Remove these OS specific preprocessor text
32#         inserted by the preprocessor.
33# 3) diff the generated file and the canons (.pp files already in
34#    the repository).
35# 4) delete the .out file that is generated.
36#
37# If the diff fails, the generated file is not removed. This will
38# be useful for analysis of ABI differences (e.g. using a visual
39# diff tool).
40#
41# A ABI change that causes a build to fail will always be accompanied
42# by new canons (.out files). The .out files that are not removed will
43# be replaced as the new .pp files.
44#
45# e.g. If include/mysql/plugin.h has an ABI change then this rule would
46# leave a <build directory>/abi_check.out file.
47#
48# A developer with a justified API change will then do a
49# mv <build directory>/abi_check.out include/mysql/plugin.pp
50# to replace the old canons with the new ones.
51#
52
53SET(abi_check_out ${BINARY_DIR}/abi_check.out)
54
55FOREACH(file ${ABI_HEADERS})
56  GET_FILENAME_COMPONENT(header_basename ${file} NAME)
57  SET(tmpfile ${BINARY_DIR}/${header_basename}.pp.tmp)
58
59  EXECUTE_PROCESS(
60    COMMAND ${COMPILER}
61      -E -nostdinc -DMYSQL_ABI_CHECK -D__cplusplus
62      -I${SOURCE_DIR}/include
63      -I${BINARY_DIR}/include -I${SOURCE_DIR}/include/mysql -I${SOURCE_DIR}/sql
64      ${file}
65      ERROR_QUIET OUTPUT_FILE ${tmpfile})
66  EXECUTE_PROCESS(
67    COMMAND sed -e "/^# /d"
68                -e "/^[	]*$/d"
69                -e "/^#pragma GCC set_debug_pwd/d"
70                -e "/^#ident/d"
71    RESULT_VARIABLE result OUTPUT_FILE ${abi_check_out} INPUT_FILE ${tmpfile})
72  IF(NOT ${result} EQUAL 0)
73    MESSAGE(FATAL_ERROR "sed returned error ${result}")
74  ENDIF()
75  FILE(REMOVE ${tmpfile})
76  EXECUTE_PROCESS(
77    COMMAND diff -w ${file}.pp ${abi_check_out} RESULT_VARIABLE result)
78  IF(result MATCHES "No such file or directory")
79    MESSAGE("Command 'diff' not found. ABI check for ${file} skipped.")
80  ELSEIF(NOT result EQUAL 0)
81    IF(ABI_UPDATE)
82      EXECUTE_PROCESS(COMMAND mv -v ${abi_check_out} ${file}.pp)
83    ELSE(ABI_UPDATE)
84      MESSAGE(FATAL_ERROR
85        "ABI check found difference between ${file}.pp and ${abi_check_out}")
86    ENDIF(ABI_UPDATE)
87  ENDIF()
88  FILE(REMOVE ${abi_check_out})
89ENDFOREACH()
90