set up cc/c++ executables

2 files changed, 99 insertions, 1 deletions

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 3f5dd8f..edd9662 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -15,6 +15,7 @@ jobs:
       matrix:
         platform: [x86, x64]
         cygwin: [0, 1]
+        hardlinks: [0, 1]
         os: [ubuntu-18.04, windows-2019, windows-2016]
 
         include:
@@ -28,10 +29,12 @@ jobs:
           - {os: ubuntu-18.04, cygwin: 1}
           # Cygwin is the same on Windows Server 2016 & 2019.
           - {os: windows-2016, cygwin: 1}
+          # Only test hardlinks on Cygwin.
+          - {cygwin: 0, hardlinks: 1}
 
     runs-on: '${{ matrix.os }}'
 
-    name: '${{ matrix.name }} / ${{ matrix.platform }}'
+    name: '${{ matrix.name }} / ${{ matrix.platform }} / Hardlinks: ${{ matrix.hardlinks }}'
 
     defaults:
       run:
@@ -55,6 +58,8 @@ jobs:
         with:
           platform: '${{ matrix.platform }}'
           cygwin: '${{ matrix.cygwin }}'
+          cc: 1
+          hardlinks: '${{ matrix.hardlinks }}'
 
       - name: Build foo.exe
         run: |
@@ -77,3 +82,26 @@ jobs:
           $actual
           "@)
         if: runner.os == 'Windows'
+
+      # Is this really the most stable piece of `gcc --version` output?
+      - name: Check cc/c++
+        run: |
+          echo (Get-Command cc).Path
+          $cc = & cc --version
+          echo $cc
+          $($cc | Select-String -Pattern "This is free software; see the source for copying conditions." -SimpleMatch -Quiet) -or $(throw "Unexpected `cc --version` output")
+          echo (Get-Command c++).Path
+          $cxx = & c++ --version
+          echo $cxx
+          $($cxx | Select-String -Pattern "This is free software; see the source for copying conditions." -SimpleMatch -Quiet) -or $(throw "Unexpected `c++ --version` output")
+        if: '!matrix.cygwin || matrix.hardlinks'
+
+      - name: Check cc/c++ on Cygwin
+        run: |
+          $cc = bash.exe --login -o errexit -c 'cc --version'
+          echo $cc
+          $($cc | Select-String -Pattern "This is free software; see the source for copying conditions." -SimpleMatch -Quiet) -or $(throw "Unexpected `cc --version` output")
+          $cxx = bash.exe --login -o errexit -c 'c++ --version'
+          echo $cxx
+          $($cxx | Select-String -Pattern "This is free software; see the source for copying conditions." -SimpleMatch -Quiet) -or $(throw "Unexpected `c++ --version` output")
+        if: matrix.cygwin && !matrix.hardlinks
diff --git a/action.yml b/action.yml
index b80d49c..93f250a 100644
--- a/action.yml
+++ b/action.yml
@@ -14,6 +14,14 @@ inputs:
     description: Enable static linking workaround
     required: false
     default: 1
+  cc:
+    description: Set up cc/c++ executables
+    required: false
+    default: 1
+  hardlinks:
+    description: On Cygwin, replace executable symlinks with hardlinks
+    required: false
+    default: 0
 
 outputs:
   prefix:
@@ -177,6 +185,68 @@ runs:
         echo "::set-output name=windres::$windres"
       shell: pwsh
 
+    - run: |
+        New-Variable os -Value '${{ runner.os }}' -Option Constant
+
+        New-Variable linux_host -Value ($os -eq 'Linux') -Option Constant
+        New-Variable cygwin_host -Value ('${{ inputs.cygwin }}' -eq '1') -Option Constant
+        New-Variable windows_host -Value ($os -eq 'Windows' -and !$cygwin_host) -Option Constant
+
+        New-Variable cc -Value ('${{ inputs.cc }}' -eq '1') -Option Constant
+
+        function Link-Exe {
+            param(
+                [Parameter(Mandatory=$true)]
+                [string] $Exe,
+                [Parameter(Mandatory=$true)]
+                [string] $LinkName
+            )
+
+            $exe_path = (Get-Command $Exe).Path
+            $link_dir = if ($script:windows_host) { Split-Path $exe_path } else { '/usr/local/bin' }
+            $link_name = if ($script:windows_host) { "$LinkName.exe" } else { $LinkName }
+            $link_path = if ($script:cygwin_host) { "$link_dir/$link_name" } else { Join-Path $link_dir $link_name }
+            echo "Creating link $link_path -> $exe_path"
+            if ($script:linux_host) {
+                sudo ln -f -s $exe_path $link_path
+            } elseif ($script:cygwin_host) {
+                ln.exe -f -s $exe_path $link_path
+            } elseif ($script:windows_host) {
+                New-Item -ItemType HardLink -Path $link_path -Value $exe_path -Force | Out-Null
+            }
+        }
+
+        if ($cc) {
+            Link-Exe '${{ steps.setup.outputs.gcc }}' cc
+            Link-Exe '${{ steps.setup.outputs.gxx }}' c++
+        }
+      shell: pwsh
+
+    - run: |
+        New-Variable cygwin_host -Value ('${{ inputs.cygwin }}' -eq '1') -Option Constant
+        New-Variable hardlinks -Value ('${{ inputs.hardlinks }}' -eq '1') -Option Constant
+
+        if ($cygwin_host -and $hardlinks) {
+            echo @'
+        while IFS= read -d '' -r link_path; do
+            dest_path="$( readlink --canonicalize-existing -- "$link_path" )"
+            dest_ext=".${dest_path##*.}"
+            [ "$dest_ext" == ".$dest_path" ] && dest_ext=
+            link_ext=".${link_path##*.}"
+            [ "$link_ext" == ".$link_path" ] && link_ext=
+            echo "Removing symlink $link_path" && rm -f -- "$link_path"
+            [ "$link_ext" != "$dest_ext" ] && echo "${PATHEXT//\;/
+        }" | grep -q --ignore-case --line-regexp -F -- "$dest_ext" && link_path="$link_path$dest_ext"
+            echo "Creating hardlink $link_path -> $dest_path" && ln -- "$dest_path" "$link_path"
+        done < <( find /usr/local/bin /usr/bin \
+                       -type l '-(' \
+                       -path /usr/local/bin/cc -o \
+                       -path /usr/local/bin/c++ \
+                       '-)' -print0 )
+        '@ | & bash.exe --login -o errexit -o nounset -o pipefail -o igncr
+        }
+      shell: pwsh
+
 branding:
   icon: star
   color: green