cmake: mimic behavior of Makefile properly. Add test to be sure.

.cirrus.yml

@@ -2,8 +2,7 @@ check_ubu1804_task:
   container:
     dockerfile: tooling/cirrus/ubu1804/Dockerfile
   test_script:
-    - cc --version
-    - mkdir btmp; cd btmp; cmake -G Ninja .. && ninja && ctest -V
+    - sh tooling/test-cmake.sh && sh tooling/pkgcheck.sh
   always:
     junit_artifacts:
       path: "btmp/*-results.xml"
@@ -14,8 +13,7 @@ check_ubu2004_task:
   container:
     dockerfile: tooling/cirrus/ubu2004/Dockerfile
   test_script:
-    - cc --version
-    - mkdir btmp; cd btmp; cmake -G Ninja .. && ninja && ctest -V
+    - sh tooling/test-cmake.sh && sh tooling/pkgcheck.sh
   always:
     junit_artifacts:
       path: "btmp/*-results.xml"
@@ -28,9 +26,7 @@ check_mac_task:
   install_script:
     - brew install ninja
   test_script:
-    - cc --version
-    - ninja --version
-    - mkdir btmp; cd btmp; cmake -G Ninja .. && cmake --build . && ctest -V
+    - sh tooling/test-cmake.sh && sh tooling/pkgcheck.sh
   always:
     junit_artifacts:
       path: "btmp/*-results.xml"
@@ -43,8 +39,7 @@ check_bsd_task:
   install_script:
     - pkg install -y gcc cmake ninja
   test_script:
-    - cc --version
-    - mkdir btmp; cd btmp; cmake -G Ninja .. && ninja && ctest -V
+    - sh tooling/test-cmake.sh && sh tooling/pkgcheck.sh
   always:
     junit_artifacts:
       path: "btmp/*-results.xml"

CMakeLists.txt

@@ -3,6 +3,12 @@ set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS ON)
 
 project(zlib C)
 
+# parse the full version number from zlib.h and include in ZLIB_FULL_VERSION
+file(READ ${CMAKE_CURRENT_SOURCE_DIR}/zlib.h _zlib_h_contents)
+string(REGEX REPLACE ".*#define[ \t]+ZLIB_VERSION[ \t]+\"([-0-9A-Za-z.]+)\".*"
+    "\\1" ZLIB_FULL_VERSION ${_zlib_h_contents})
+MESSAGE("ZLIB_FULL_VERSION=${ZLIB_FULL_VERSION}")
+# FIXME: parse this from ZLIB_FULL_VERSION
 set(VERSION "1.2.11.1")
 
 option(ASM686 "Enable building i686 assembly implementation")
@@ -12,7 +18,16 @@ set(INSTALL_BIN_DIR "${CMAKE_INSTALL_PREFIX}/bin" CACHE PATH "Installation direc
 set(INSTALL_LIB_DIR "${CMAKE_INSTALL_PREFIX}/lib" CACHE PATH "Installation directory for libraries")
 set(INSTALL_INC_DIR "${CMAKE_INSTALL_PREFIX}/include" CACHE PATH "Installation directory for headers")
 set(INSTALL_MAN_DIR "${CMAKE_INSTALL_PREFIX}/share/man" CACHE PATH "Installation directory for manual pages")
-set(INSTALL_PKGCONFIG_DIR "${CMAKE_INSTALL_PREFIX}/share/pkgconfig" CACHE PATH "Installation directory for pkgconfig (.pc) files")
+set(INSTALL_PKGCONFIG_DIR "${INSTALL_LIB_DIR}/pkgconfig" CACHE PATH "Installation directory for pkgconfig (.pc) files")
+
+# Set a default build type if none was specified
+set(default_build_type "Release")
+if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
+  message(STATUS "Setting build type to '${default_build_type}' as none was specified.")
+  set(CMAKE_BUILD_TYPE "${default_build_type}" CACHE STRING "Choose the type of build." FORCE)
+  # Set the possible values of build type for cmake-gui
+  set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS "Debug" "Release" "MinSizeRel" "RelWithDebInfo")
+endif()
 
 include(CheckTypeSize)
 include(CheckFunctionExists)
@@ -23,6 +38,33 @@ enable_testing()
 check_include_file(sys/types.h HAVE_SYS_TYPES_H)
 check_include_file(stdint.h    HAVE_STDINT_H)
 check_include_file(stddef.h    HAVE_STDDEF_H)
+check_include_file(stdarg.h    HAVE_STDARG_H)
+check_include_file(unistd.h    HAVE_UNISTD_H)
+
+#
+# Match configure's zconf.h exactly
+#
+if (HAVE_STDARG_H)
+  SET(ZCONF_STDARG_LINE "#if 1    /* was set to #if 1 by ./configure */")
+else()
+  SET(ZCONF_STDARG_LINE "#ifdef HAVE_STDARG_H    /* may be set to #if 1 by ./configure */")
+endif()
+if (HAVE_UNISTD_H)
+  SET(ZCONF_UNISTD_LINE "#if 1    /* was set to #if 1 by ./configure */")
+else()
+  SET(ZCONF_UNISTD_LINE "#ifdef HAVE_UNISTD_H    /* may be set to #if 1 by ./configure */")
+endif()
+
+#
+# Check to see if compiler supports __attribute__((visibility ("hidden")))
+#
+check_c_source_compiles(
+    "int __attribute__((visibility (\"hidden\"))) foo; int main() { return foo; }"
+    HAVE_HIDDEN
+)
+if(HAVE_HIDDEN)
+    add_definitions(-DHAVE_HIDDEN)
+endif()
 
 #
 # Check to see if we have large file support
@@ -54,11 +96,6 @@ if(NOT HAVE_FSEEKO)
     add_definitions(-DNO_FSEEKO)
 endif()
 
-#
-# Check for unistd.h
-#
-check_include_file(unistd.h Z_HAVE_UNISTD_H)
-
 if(MSVC)
     set(CMAKE_DEBUG_POSTFIX "d")
     add_definitions(-D_CRT_SECURE_NO_DEPRECATE)
@@ -78,6 +115,19 @@ if(NOT CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_CURRENT_BINARY_DIR)
   endif()
 endif()
 
+# Refer to prefix symbolically to ease relocation by end user,
+# and match Makefile-generate .pc file exactly.
+if(INSTALL_INC_DIR STREQUAL "${CMAKE_INSTALL_PREFIX}/include")
+  set(PC_INSTALL_INC_DIR "\${prefix}/include")
+else()
+  set(PC_INSTALL_INC_DIR "${INSTALL_INC_DIR}")
+endif()
+if(INSTALL_LIB_DIR STREQUAL "${CMAKE_INSTALL_PREFIX}/lib")
+  set(PC_INSTALL_LIB_DIR "\${exec_prefix}/lib")
+else()
+  set(PC_INSTALL_LIB_DIR "${INSTALL_LIB_DIR}")
+endif()
+
 set(ZLIB_PC ${CMAKE_CURRENT_BINARY_DIR}/zlib.pc)
 configure_file( ${CMAKE_CURRENT_SOURCE_DIR}/zlib.pc.cmakein
 		${ZLIB_PC} @ONLY)
@@ -105,22 +155,27 @@ set(ZLIB_PRIVATE_HDRS
     trees.h
     zutil.h
 )
+
+# Note: keep these in the same order as in Makefile.in
+# This allows libz.so to be identical between the two build systems.
 set(ZLIB_SRCS
+    # Makefile.in: PIC_OBJZ
     adler32.c
-    compress.c
     crc32.c
     deflate.c
-    gzclose.c
-    gzlib.c
-    gzread.c
-    gzwrite.c
-    inflate.c
     infback.c
-    inftrees.c
     inffast.c
+    inflate.c
+    inftrees.c
     trees.c
-    uncompr.c
     zutil.c
+    # Makefile.in: PIC_OBJG
+    compress.c
+    uncompr.c
+    gzclose.c
+    gzlib.c
+    gzread.c
+    gzwrite.c
 )
 
 if(NOT MINGW)
@@ -162,11 +217,6 @@ if(MSVC)
 	endif()
 endif()
 
-# parse the full version number from zlib.h and include in ZLIB_FULL_VERSION
-file(READ ${CMAKE_CURRENT_SOURCE_DIR}/zlib.h _zlib_h_contents)
-string(REGEX REPLACE ".*#define[ \t]+ZLIB_VERSION[ \t]+\"([-0-9A-Za-z.]+)\".*"
-    "\\1" ZLIB_FULL_VERSION ${_zlib_h_contents})
-
 if(MINGW)
     # This gets us DLL resource information when compiling on MinGW.
     if(NOT CMAKE_RC_COMPILER)
@@ -199,6 +249,16 @@ if(NOT CYGWIN)
     set_target_properties(zlib PROPERTIES VERSION ${ZLIB_FULL_VERSION})
 endif()
 
+if(APPLE)
+   set_target_properties(zlib PROPERTIES
+       INSTALL_NAME_DIR "${CMAKE_INSTALL_PREFIX}/lib"
+      )
+elseif (UNIX)
+     # Makefile.in uses -lc...
+     set(LDSHAREDLIBC -lc)
+     target_link_libraries(zlib ${LDSHAREDLIBC})
+endif()
+
 if(UNIX)
     # On unix-like platforms the library is almost always called libz
    set_target_properties(zlib zlibstatic PROPERTIES OUTPUT_NAME z)

configure

@@ -25,7 +25,7 @@ if test $SRCDIR = "."; then
     ZINCOUT="-I."
     SRCDIR=""
 else
-    ZINC='-include zconf.h'
+    ZINC='-I. -include zconf.h'
     ZINCOUT='-I. -I$(SRCDIR)'
     SRCDIR="$SRCDIR/"
 fi

tooling/cirrus/ubu1804/Dockerfile

@@ -1,5 +1,5 @@
 FROM ubuntu:18.04
 
 RUN apt-get update && \
-    apt-get install --no-install-recommends -y cmake gcc libc6-dev ninja-build && \
+    apt-get install --no-install-recommends -y cmake gcc libc6-dev ninja-build make && \
     apt-get clean

tooling/cirrus/ubu2004/Dockerfile

@@ -1,5 +1,5 @@
 FROM ubuntu:20.04
 
 RUN apt-get update && \
-    apt-get install --no-install-recommends -y cmake gcc libc6-dev ninja-build && \
+    apt-get install --no-install-recommends -y cmake gcc libc6-dev ninja-build make && \
     apt-get clean

tooling/pkgcheck.sh

@@ -0,0 +1,83 @@
+#!/bin/sh
+# Verify that the various build systems produce identical results on a Unixlike system
+set -ex
+
+# Tell GNU's ld etc. to use Jan 1 1970 when embedding timestamps
+export SOURCE_DATE_EPOCH=0
+# Tell Apple's ar etc. to use zero timestamps
+export ZERO_AR_DATE=1
+
+# Original build system
+rm -rf btmp1 pkgtmp1
+mkdir btmp1 pkgtmp1
+export DESTDIR=$(pwd)/pkgtmp1
+cd btmp1
+  case $(uname) in
+  Darwin)
+    # Tell configure which compiler etc. to use to match cmake
+    # Tell configure to pad the executable the same way cmake will
+    CC="$(xcrun --find gcc || echo gcc)" \
+    CFLAGS="-DNDEBUG -O3 -isysroot $(xcrun --show-sdk-path)" \
+    LDFLAGS="-Wl,-headerpad_max_install_names" \
+    ../configure
+    ;;
+  FreeBSD)
+    # 1) tell configure to tell ar to be deterministic?
+    # 2) configure fails with cc, so use clang or gcc
+    # 3) Force same CC for configure and clang
+    #export ARFLAGS="Drc"
+    if clang --version
+    then
+        export CC=clang
+        ../configure
+    elif gcc --version
+    then
+        export CC=gcc
+        ../configure
+    else
+        # will probably fail
+        ../configure
+    fi
+    ;;
+  *)
+    ../configure
+    ;;
+  esac
+  make
+  make install
+cd ..
+
+# New build system
+rm -rf btmp2 pkgtmp2
+mkdir btmp2 pkgtmp2
+export DESTDIR=$(pwd)/pkgtmp2
+cd btmp2
+  cmake -G Ninja ..
+  ninja -v
+  ninja install
+cd ..
+
+case $(uname) in
+Darwin)
+  # Alas, dylibs still have an embedded hash or something,
+  # so nuke it.  There's probably a better way.
+  dylib1=$(find pkgtmp1 -name '*.dylib*' -type f)
+  dylib2=$(find pkgtmp2 -name '*.dylib*' -type f)
+  dd conv=notrunc if=/dev/zero of=$dylib1 skip=1337 count=16
+  dd conv=notrunc if=/dev/zero of=$dylib2 skip=1337 count=16
+  ;;
+FreeBSD)
+  # I had trouble passing -D to the ar inside CMakeLists.txt,
+  # so punt and unpack the archive before comparing.
+  cd pkgtmp1; ar x usr/local/lib/libz.a; rm usr/local/lib/libz.a; cd ..
+  cd pkgtmp2; ar x usr/local/lib/libz.a; rm usr/local/lib/libz.a; cd ..
+  ;;
+esac
+
+if diff -Nur pkgtmp1 pkgtmp2
+then
+  echo pkgcheck-cmake-bits-identical PASS
+else
+  echo pkgcheck-cmake-bits-identical FAIL
+  exit 1
+fi

tooling/test-cmake.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+# Build and test with CMake
+set -ex
+
+rm -rf btmp
+mkdir btmp
+cd btmp
+  cmake -G Ninja ..
+  ninja
+  ctest -V
+cd ..

tooling/test-make.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+# Build and test with Make
+set -ex
+
+rm -rf btmp
+mkdir btmp
+cd btmp1
+  ../configure
+  make
+  make test
+cd ..

zconf.h.cmakein

@@ -7,8 +7,6 @@
 
 #ifndef ZCONF_H
 #define ZCONF_H
-#cmakedefine Z_PREFIX
-#cmakedefine Z_HAVE_UNISTD_H
 
 /*
  * If you *really* need a unique prefix for all types and library functions,
@@ -433,11 +431,11 @@ typedef uLong FAR uLongf;
    typedef unsigned long z_crc_t;
 #endif
 
-#ifdef HAVE_UNISTD_H    /* may be set to #if 1 by ./configure */
+@ZCONF_UNISTD_LINE@
 #  define Z_HAVE_UNISTD_H
 #endif
 
-#ifdef HAVE_STDARG_H    /* may be set to #if 1 by ./configure */
+@ZCONF_STDARG_LINE@
 #  define Z_HAVE_STDARG_H
 #endif
 

zlib.pc.cmakein

@@ -1,12 +1,12 @@
 prefix=@CMAKE_INSTALL_PREFIX@
-exec_prefix=@CMAKE_INSTALL_PREFIX@
-libdir=@INSTALL_LIB_DIR@
-sharedlibdir=@INSTALL_LIB_DIR@
-includedir=@INSTALL_INC_DIR@
+exec_prefix=${prefix}
+libdir=@PC_INSTALL_LIB_DIR@
+sharedlibdir=${libdir}
+includedir=@PC_INSTALL_INC_DIR@
 
 Name: zlib
 Description: zlib compression library
-Version: @VERSION@
+Version: @ZLIB_FULL_VERSION@
 
 Requires:
 Libs: -L${libdir} -L${sharedlibdir} -lz