configure

#!/bin/sh
# Anticonf (tm) script by Jeroen Ooms (2020)
PKG_CONFIG_NAME="opencv4"
PKG_CONFIG_NAME_ALT="opencv"
PKG_DEB_NAME="libopencv-dev"
PKG_RPM_NAME="opencv-devel"
PKG_BREW_NAME="opencv"
PKG_TEST_HEADER="<opencv2/opencv.hpp>"
PKG_TEST_HEADER_XFEATURES2D="<opencv2/xfeatures2d.hpp>"
PKG_LIBS="-lopencv_{stitching,superres,videostab,aruco,bgsegm,bioinspired,ccalib,dnn_objdetect,\
dpm,face,photo,fuzzy,hfs,img_hash,line_descriptor,optflow,reg,rgbd,saliency,stereo,structured_light,\
phase_unwrapping,surface_matching,tracking,datasets,dnn,plot,xfeatures2d,shape,video,ml,ximgproc,\
calib3d,features2d,highgui,videoio,flann,xobjdetect,imgcodecs,objdetect,xphoto,imgproc,core}"

# For debugging opencv3 in macos:
#export PKG_CONFIG_PATH="/usr/local/opt/opencv@3/lib/pkgconfig"

# Use pkg-config if available
PCVERSION=`pkg-config --version 2>/dev/null`
if [ $? -eq 0 ]; then
  echo "This is pkg-config $PCVERSION"
  if pkg-config --exists ${PKG_CONFIG_NAME} ; then
    PKGCONFIG_CFLAGS=`pkg-config --cflags ${PKG_CONFIG_NAME}`
    PKGCONFIG_LIBS=`pkg-config --libs ${PKG_CONFIG_NAME}`
    PKGCONFIG_PREFIX=`pkg-config --variable=prefix ${PKG_CONFIG_NAME}`
  elif pkg-config --exists ${PKG_CONFIG_NAME_ALT}; then
    PKGCONFIG_CFLAGS=`pkg-config --cflags ${PKG_CONFIG_NAME_ALT}`
    PKGCONFIG_LIBS=`pkg-config --libs ${PKG_CONFIG_NAME_ALT}`
    PKGCONFIG_PREFIX=`pkg-config --variable=prefix ${PKG_CONFIG_NAME_ALT}`
  fi
fi

# Note that cflags may be empty in case of success
if [ "$PKGCONFIG_CFLAGS" ] || [ "$PKGCONFIG_LIBS" ]; then
  echo "Found pkg-config cflags and libs!"
  PKG_CFLAGS=${PKGCONFIG_CFLAGS}
  PKG_LIBS=${PKGCONFIG_LIBS}
  if [ "$PKGCONFIG_PREFIX" ]; then
    PKG_CFLAGS="$PKG_CFLAGS -D_DATA_PREFIX=${PKGCONFIG_PREFIX}"
  fi
elif [ `uname` = "Darwin" ]; then
  test ! "$CI" && brew --version 2>/dev/null
  if [ $? -eq 0 ]; then
    BREWDIR=`brew --prefix`
    PKG_CFLAGS="-I$BREWDIR/opt/opencv/include"
    PKG_LIBS="-L$BREWDIR/opt/opencv/lib $PKG_LIBS"
  else
    curl -sfL "https://autobrew.github.io/scripts/opencv" > autobrew
    . ./autobrew
  fi
fi

# For debugging
echo "Using PKG_CFLAGS=$PKG_CFLAGS"
echo "Using PKG_LIBS=$PKG_LIBS"

# Use CXX17 if available (preferred for recent opencv)
CXX17=`${R_HOME}/bin/R CMD config CXX17` || unset CXX17

if [ "$CXX17" ]; then
echo "Found C++17 compiler: $CXX17"
CXXVER=CXX17
else
echo "Using C++11 compiler"
CXXVER=CXX11
fi

CXX=$($R_HOME/bin/R CMD config ${CXXVER})
CXXSTD=$($R_HOME/bin/R CMD config ${CXXVER}STD)
CXXFLAGS="$($R_HOME/bin/R CMD config ${CXXVER}FLAGS)"
CPPFLAGS="$($R_HOME/bin/R CMD config CPPFLAGS)"
CXXCPP="$CXX $CXXSTD -E"

# Test configuration
echo "#include $PKG_TEST_HEADER" | ${CXXCPP} ${CPPFLAGS} ${PKG_CFLAGS} ${CXXFLAGS} -xc++ - >/dev/null 2>configure.log

if [ $? -ne 0 ]; then
  echo "-----------------------------[ ANTICONF ]-------------------------------"
  echo "Configuration failed to find $PKG_CONFIG_NAME library. Try installing:"
  echo " * deb: $PKG_DEB_NAME (Debian, Ubuntu, etc)"
  echo " * rpm: $PKG_RPM_NAME (Fedora, CentOS, RHEL)"
  echo " * brew: $PKG_BREW_NAME (Mac OSX)"
  echo "If $PKG_CONFIG_NAME is already installed, check that 'pkg-config' is in your"
  echo "PATH and PKG_CONFIG_PATH contains a $PKG_CONFIG_NAME.pc file."
  echo "---------------------------[ ERROR MESSAGE ]----------------------------"
  cat configure.log
  echo "------------------------------------------------------------------------"
  exit 1
fi

echo "#include $PKG_TEST_HEADER_XFEATURES2D" | ${CXXCPP} ${CPPFLAGS} ${PKG_CFLAGS}  ${CXXFLAGS} -xc++ - >/dev/null 2>>configure.log
if [ $? -ne 0 ]; then
  echo "Module $PKG_TEST_HEADER_XFEATURES2D has not been found on your system, disabling keypoint detection."
else
  PKG_CFLAGS="$PKG_CFLAGS -DHAVE_XFEATURES2D"
fi

# Write to Makevars
sed -e "s|@cflags@|$PKG_CFLAGS|" -e "s|@libs@|$PKG_LIBS|" -e "s|CXX11|${CXXVER}|" src/Makevars.in > src/Makevars

# Success
exit 0