Fix Linux build on Debian 9

@@ -7,7 +7,7 @@ on:
     branches: [master]
 
 jobs:
-  build:
+  linux:
     runs-on: ubuntu-latest
 
     steps:
@@ -15,8 +15,10 @@ jobs:
       - uses: subosito/flutter-action@v1
         with:
           channel: stable
+      - name: Enable Linux for flutter
+        run: flutter config --enable-linux-desktop
       - name: Install utils
-        run: sudo apt install poppler-utils imagemagick
+        run: sudo apt install poppler-utils imagemagick clang cmake ninja-build pkg-config libgtk-3-dev
       - name: Run analysis
         run: make analyze
       - name: Run tests
@@ -27,3 +29,11 @@ jobs:
         run: test -z "$(git status --porcelain)"
       - name: Push to codecov
         run: bash <(curl -s https://codecov.io/bash)
+      - name: Prepare build
+        run: cd printing/example; flutter create -t app --no-overwrite --org net.nfet --project-name example .
+      - name: Build example for Linux
+        run: cd printing/example; flutter build -v linux
+      - name: Build example for Android
+        run: cd printing/example; flutter build -v apk
+      - name: Build demo for Web
+        run: cd demo; flutter build -v web

@@ -4,6 +4,7 @@
 
 - Fix raster crash on all OS.
 - Improve PdfPreview widget
+- Fix Linux build on Debian 9
 
 ## 5.2.1
 

@@ -20,6 +20,7 @@
 #include <sys/mman.h>
 #include <sys/types.h>
 #include <sys/wait.h>
+#include <cstring>
 #include <string>
 
 #include <fpdfview.h>

@@ -17,6 +17,10 @@
 #ifndef PRINTING_PLUGIN_PRINT_JOB_H_
 #define PRINTING_PLUGIN_PRINT_JOB_H_
 
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE 1
+#endif
+
 #include <flutter_linux/flutter_linux.h>
 #include <gtk/gtk.h>
 #include <gtk/gtkunixprint.h>

@@ -16,6 +16,7 @@
 
 #include "include/printing/printing_plugin.h"
 
+#include <cstring>
 #include <memory>
 
 #include <flutter_linux/flutter_linux.h>