Fix issues for running on Windows

.azure-pipelines.yml

@@ -155,7 +155,6 @@ jobs:
 ########################################################################################
 - job:
   displayName: 'Windows'
-  condition: False
 
   pool:
     vmImage: 'vs2017-win2016'
@@ -173,18 +172,12 @@ jobs:
       Python37:
         python.version: '3.7'
         PYTHON: '3.7'
-      Python36:
-        python.version: '3.6'
-        PYTHON: '3.6'
+      #Python36:
+        #python.version: '3.6'
+        #PYTHON: '3.6'
 
   steps:
 
-  # Install ghostscript separately since there is no Windows conda-forge package for it.
-  - bash: |
-      set -x -e
-      choco install ghostscript
-    displayName: Install ghostscript via chocolatey
-
   - powershell: Write-Host "##vso[task.prependpath]$env:CONDA\Scripts"
     displayName: Add conda to PATH
 
@@ -203,6 +196,13 @@ jobs:
       conda list
     displayName: List installed packages
 
+  # Download latest GMT
+  - script: git clone --branch=master --depth=1 https://github.com/GenericMappingTools/gmt.git
+    displayName: Download GMT
+
+  # Build GMT
+  - template: ci/azure-pipelines-windows.yml
+
   # Install the package that we want to test
   - bash: |
       set -x -e

Makefile

@@ -23,9 +23,9 @@ install:
 test:
 	# Run a tmp folder to make sure the tests are run on the installed version
 	mkdir -p $(TESTDIR)
-	@echo ""
-	@cd $(TESTDIR); python -c "import $(PROJECT); $(PROJECT).print_clib_info()"
-	@echo ""
+	#@echo ""
+	#@cd $(TESTDIR); python -c "import $(PROJECT); $(PROJECT).print_clib_info()"
+	#@echo ""
 	cd $(TESTDIR); pytest $(PYTEST_ARGS) $(PROJECT)
 	cp $(TESTDIR)/.coverage* .
 	rm -r $(TESTDIR)

ci/azure-pipelines-windows.yml

@@ -0,0 +1,88 @@
+# Template for Windows steps in Azure Pipelines
+
+steps:
+
+# Cache vcpkg installed libraries
+# Currently, caches are immutable and can't be updated.
+# To rebuild the cache, you have to change the date in the key list
+- task: CacheBeta@0
+  inputs:
+    key: $(Agent.OS) | vcpkg | 20190802
+    path: $(VCPKG_INSTALLATION_ROOT)/installed/
+    cacheHitVar: CACHE_VCPKG_RESTORED
+  displayName: Cache vcpkg libraries
+
+- bash: |
+    set -x -e
+    # By default, vcpkg builds both release and debug configurations.
+    # Set VCPKG_BUILD_TYPE to build release only to save half time
+    echo 'set (VCPKG_BUILD_TYPE release)' >> ${VCPKG_INSTALLATION_ROOT}/triplets/${WIN_PLATFORM}.cmake
+    cat ${VCPKG_INSTALLATION_ROOT}/triplets/${WIN_PLATFORM}.cmake
+    # install libraries
+    #vcpkg install netcdf-c gdal pcre fftw3 clapack openblas --triplet ${WIN_PLATFORM}
+    vcpkg install netcdf-c gdal pcre fftw3 --triplet ${WIN_PLATFORM}
+  displayName: Install dependencies via vcpkg
+  env:
+    WIN_PLATFORM: "x64-windows"
+  condition: ne(variables['CACHE_VCPKG_RESTORED'], true)
+
+- bash: |
+    # hook up user-wide integration
+    vcpkg integrate install
+    # list installed libraries
+    vcpkg list
+    # Executable files search for DLL files in the directories listed in the PATH environment variable.
+    echo "##vso[task.prependpath]${VCPKG_INSTALLATION_ROOT}/installed/${WIN_PLATFORM}/bin"
+    # Tools like gdal_translate, ogr2ogr are located in tools/gdal
+    echo "##vso[task.prependpath]${VCPKG_INSTALLATION_ROOT}/installed/${WIN_PLATFORM}/tools/gdal"
+  displayName: Configure vcpkg
+  env:
+    WIN_PLATFORM: "x64-windows"
+
+- bash: |
+    set -x -e
+    choco install ninja
+    choco install ghostscript --version 9.26 # gs 9.27 is buggy
+  displayName: Install dependencies via chocolatey
+
+- bash: |
+    echo "##vso[task.setvariable variable=INSTALLDIR]$BUILD_SOURCESDIRECTORY/gmt-install-dir"
+    echo "##vso[task.setvariable variable=COASTLINEDIR]$BUILD_SOURCESDIRECTORY/coastline"
+  displayName: Set install location and coastline location
+
+- bash: echo "##vso[task.prependpath]$INSTALLDIR/bin"
+  displayName: Set PATH
+
+- task: CacheBeta@0
+  inputs:
+    key: coastline
+    path: $(COASTLINEDIR)
+    cacheHitVar: CACHE_COASTLINE_RESTORED
+  displayName: Cache GSHHG and DCW data
+
+- bash: ci/download-coastlines.sh
+  displayName: Download coastlines
+  condition: ne(variables['CACHE_COASTLINE_RESTORED'], true)
+
+- bash: ci/config-gmt-windows.sh
+  displayName: Configure GMT
+
+# Azure Pipelines cannot find Visual Studio correctly if Ninja is used.
+# Here, we need
+# 1. call the vcvars64.bat script
+# 2. define CMAKE_C_COMPILER
+- script: |
+    mkdir build
+    cd build
+    call "C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\VC\Auxiliary\Build\vcvars64.bat"
+    cmake .. -G "Ninja" -DCMAKE_TOOLCHAIN_FILE=%VCPKG_INSTALLATION_ROOT%\scripts\buildsystems\vcpkg.cmake -DCMAKE_C_COMPILER=cl.exe -DCMAKE_BUILD_TYPE=Release
+    cmake --build .
+    cmake --build . --target install
+  displayName: Compile GMT
+
+- script: |
+    gmt --version
+    gmt defaults -Vd
+    gmt pscoast -R0/10/0/10 -JM6i -Ba -Ggray -ENG+p1p,blue -P -Vd > test.ps
+    gmt begin && gmt coast -R0/10/0/10 -JM6i -Ba -Ggray -ENG+p1p,blue -Vd && gmt end
+  displayName: Check a few simple commands

ci/config-gmt-windows.sh

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+# Build and install GMT
+
+# To return a failure if any commands inside fail
+set -e
+
+cat > cmake/ConfigUser.cmake << 'EOF'
+set (CMAKE_INSTALL_PREFIX "$ENV{INSTALLDIR}")
+set (GSHHG_ROOT "$ENV{COASTLINEDIR}/gshhg")
+set (DCW_ROOT "$ENV{COASTLINEDIR}/dcw")
+set (COPY_GSHHG TRUE)
+set (COPY_DCW TRUE)
+set (GMT_INSTALL_MODULE_LINKS FALSE)
+set (CMAKE_C_FLAGS "/D_CRT_SECURE_NO_WARNINGS /D_CRT_SECURE_NO_DEPRECATE ${CMAKE_C_FLAGS}")
+set (CMAKE_C_FLAGS "/D_CRT_NONSTDC_NO_DEPRECATE /D_SCL_SECURE_NO_DEPRECATE ${CMAKE_C_FLAGS}")
+EOF
+
+if [[ "$TEST" == "true" ]]; then
+    cat >> cmake/ConfigUser.cmake << 'EOF'
+enable_testing()
+set (DO_EXAMPLES TRUE)
+set (DO_TESTS TRUE)
+set (DO_API_TESTS ON)
+set (SUPPORT_EXEC_IN_BINARY_DIR TRUE)
+EOF
+fi
+
+if [[ "$BUILD_DOCS" == "true" ]]; then
+    cat >> cmake/ConfigUser.cmake << 'EOF'
+set (DO_ANIMATIONS TRUE)
+set (CMAKE_VERBOSE_MAKEFILE ON CACHE BOOL "ON")
+EOF
+fi
+
+echo ""
+echo "Using the following cmake configuration:"
+cat cmake/ConfigUser.cmake
+echo ""
+
+# Turn off exit on failure.
+set +e

ci/download-coastlines.sh

@@ -0,0 +1,55 @@
+#!/usr/bin/env bash
+# Download and install the coastlines and boundaries datasets
+
+# General settings:
+EXT="tar.gz"
+GSHHG="gshhg-gmt-2.3.7"
+DCW="dcw-gmt-1.1.4"
+MD5_GSHHG=8ee2653f9daf84d49fefbf990bbfa1e7
+MD5_DCW=4f30857a8b12af0f910222fceb591538
+
+# Used for checking the downloaded files:
+check_md5 ()
+{
+  md5_ref=$1
+  file=$2
+
+  test -f "$file" || return 1
+  md5=$(openssl dgst -md5 $file | cut -d ' ' -f 2)
+  test "$md5" = "$md5_ref"
+}
+
+# To return a failure if any commands inside fail
+set -e
+
+# Create the directory for coastline data
+mkdir -p $COASTLINEDIR
+
+# GSHHG and DCW tarballs are cached here:
+test -d $HOME/cache-gshhg-dcw || mkdir $HOME/cache-gshhg-dcw
+cd $HOME/cache-gshhg-dcw
+
+# GSHHG (coastlines, rivers, and political boundaries):
+echo ""
+echo "Downloading and unpacking GSHHG"
+echo "================================================================================"
+# download when md5sums don't match:
+check_md5 $MD5_GSHHG $GSHHG.$EXT || curl -L -O --retry 10 "https://mirrors.ustc.edu.cn/gmt/$GSHHG.$EXT"
+check_md5 $MD5_GSHHG $GSHHG.$EXT
+tar xzf $GSHHG.$EXT
+mv $GSHHG $COASTLINEDIR/gshhg
+
+# DCW (country polygons):
+echo ""
+echo "Downloading and unpacking DCW"
+echo "================================================================================"
+# download when md5sums don't match:
+check_md5 $MD5_DCW $DCW.$EXT || curl -L -O --retry 10 "https://mirrors.ustc.edu.cn/gmt/$DCW.$EXT"
+check_md5 $MD5_DCW $DCW.$EXT
+tar xzf $DCW.$EXT
+mv $DCW $COASTLINEDIR/dcw
+
+ls $COASTLINEDIR/gshhg $COASTLINEDIR/dcw
+
+# Turn off exit on failure.
+set +e

pygmt/clib/loading.py

@@ -37,85 +37,47 @@ def load_libgmt(env=None):
         couldn't access the functions).
 
     """
-    libpath = get_clib_path(env)
-    try:
-        libgmt = ctypes.CDLL(libpath)
-        check_libgmt(libgmt)
-    except OSError as err:
-        msg = "\n".join(
-            [
-                "Error loading the GMT shared library '{}':".format(libpath),
-                "{}".format(str(err)),
-            ]
-        )
-        raise GMTCLibNotFoundError(msg)
-    return libgmt
-
-
-def get_clib_path(env):
-    """
-    Get the path to the libgmt shared library.
-
-    Determine the file name and extension and append to the path set by
-    ``GMT_LIBRARY_PATH``, if any.
-
-    Parameters
-    ----------
-    env : dict or None
-        A dictionary containing the environment variables. If ``None``, will
-        default to ``os.environ``.
-
-    Returns
-    -------
-    libpath : str
-        The path to the libgmt shared library.
-
-    """
-    libname = clib_name()
     if env is None:
         env = os.environ
-    if "GMT_LIBRARY_PATH" in env:
-        libpath = os.path.join(env["GMT_LIBRARY_PATH"], libname)
-    else:
-        libpath = libname
-    return libpath
+    libnames = clib_name(os_name=sys.platform)
+    libpath = env.get("GMT_LIBRARY_PATH", "")
+    error = False
+    for libname in libnames:
+        try:
+            libgmt = ctypes.CDLL(os.path.join(libpath, libname))
+            check_libgmt(libgmt)
+            break
+        except OSError as err:
+            error = err
+    if error:
+        raise GMTCLibNotFoundError(
+            "Error loading the GMT shared library '{}':".format(libname)
+        )
+    return libgmt
 
 
-def clib_name(os_name=None, is_64bit=None):
+def clib_name(os_name):
     """
     Return the name of GMT's shared library for the current OS.
 
     Parameters
     ----------
-    os_name : str or None
-        The operating system name as given by ``sys.platform``
-        (the default if None).
-    is_64bit : bool or None
-        Whether or not the OS is 64bit. Only used if the OS is ``win32``. If
-        None, will determine automatically.
+    os_name : str
+        The operating system name as given by ``sys.platform``.
 
     Returns
     -------
-    libname : str
-        The name of GMT's shared library.
+    libname : list of str
+        List of possible names of GMT's shared library.
 
     """
-    if os_name is None:
-        os_name = sys.platform
-
-    if is_64bit is None:
-        is_64bit = sys.maxsize > 2 ** 32
-
     if os_name.startswith("linux"):
-        libname = "libgmt.so"
+        libname = ["libgmt.so"]
     elif os_name == "darwin":
         # Darwin is macOS
-        libname = "libgmt.dylib"
+        libname = ["libgmt.dylib"]
     elif os_name == "win32":
-        if is_64bit:
-            libname = "gmt_w64.dll"
-        else:
-            libname = "gmt_w32.dll"
+        libname = ["gmt.dll", "gmt_w64.dll", "gmt_w32.dll"]
     else:
         raise GMTOSError('Operating system "{}" not supported.'.format(sys.platform))
     return libname