1 files changed, 59 insertions, 0 deletions
diff --git a/widget/gtk/nsCUPSShim.cpp b/widget/gtk/nsCUPSShim.cpp
new file mode 100644
index 000000000..d05da307f
--- /dev/null
+++ b/widget/gtk/nsCUPSShim.cpp
@@ -0,0 +1,59 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* ex: set tabstop=8 softtabstop=4 shiftwidth=4 expandtab: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsDebug.h"
+#include "nsString.h"
+#include "nsCUPSShim.h"
+#include "mozilla/ArrayUtils.h"
+#include "prlink.h"
+
+
+// List of symbols to find in libcups. Must match symAddr[] defined in Init().
+// Making this an array of arrays instead of pointers allows storing the
+// whole thing in read-only memory.
+static const char gSymName[][sizeof("cupsPrintFile")] = {
+    { "cupsAddOption" },
+    { "cupsFreeDests" },
+    { "cupsGetDest" },
+    { "cupsGetDests" },
+    { "cupsPrintFile" },
+    { "cupsTempFd" },
+};
+static const int gSymNameCt = mozilla::ArrayLength(gSymName);
+
+
+bool
+nsCUPSShim::Init()
+{
+    mCupsLib = PR_LoadLibrary("libcups.so.2");
+    if (!mCupsLib)
+        return false;
+
+    // List of symbol pointers. Must match gSymName[] defined above.
+    void **symAddr[] = {
+        (void **)&mCupsAddOption,
+        (void **)&mCupsFreeDests,
+        (void **)&mCupsGetDest,
+        (void **)&mCupsGetDests,
+        (void **)&mCupsPrintFile,
+        (void **)&mCupsTempFd,
+    };
+
+    for (int i = gSymNameCt; i--; ) {
+        *(symAddr[i]) = PR_FindSymbol(mCupsLib, gSymName[i]);
+        if (! *(symAddr[i])) {
+#ifdef DEBUG
+            nsAutoCString msg(gSymName[i]);
+            msg.AppendLiteral(" not found in CUPS library");
+            NS_WARNING(msg.get());
+#endif
+            PR_UnloadLibrary(mCupsLib);
+            mCupsLib = nullptr;
+            return false;
+        }
+    }
+    return true;
+}