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-rw-r--r--widget/nsCUPSShim.cpp76
1 files changed, 76 insertions, 0 deletions
diff --git a/widget/nsCUPSShim.cpp b/widget/nsCUPSShim.cpp
new file mode 100644
index 0000000000..d999a1be17
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+++ b/widget/nsCUPSShim.cpp
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+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* ex: set tabstop=8 softtabstop=2 shiftwidth=2 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 "mozilla/Logging.h"
+#include "prlink.h"
+
+#ifdef CUPS_SHIM_RUNTIME_LINK
+
+mozilla::LazyLogModule gCupsLinkLog("CupsLink");
+
+# define DEBUG_LOG(...) \
+ MOZ_LOG(gCupsLinkLog, mozilla::LogLevel::Debug, (__VA_ARGS__))
+
+// TODO: This is currently pointless as we always use the compile-time linked
+// version of CUPS, but in the future this may become a configure option.
+// We also cannot use NSPR's library suffix support, since that cannot handle
+// version number suffixes.
+# ifdef XP_MACOSX
+static const char gCUPSLibraryName[] = "libcups.2.dylib";
+# else
+static const char gCUPSLibraryName[] = "libcups.so.2";
+# endif
+
+static bool LoadCupsFunc(PRLibrary* aLib, void** aDest, const char* const aName,
+ nsCUPSShim::Optional aOptional) {
+ *aDest = PR_FindSymbol(aLib, aName);
+ if (!*aDest) {
+ DEBUG_LOG("%s not found in CUPS library", aName);
+ return bool(aOptional);
+ }
+ return true;
+}
+
+nsCUPSShim::nsCUPSShim() {
+ mCupsLib = PR_LoadLibrary(gCUPSLibraryName);
+ if (!mCupsLib) {
+ DEBUG_LOG("CUPS library not found");
+ return;
+ }
+
+ bool success = true;
+
+ // This is a macro so that it could also load from libcups if we are
+ // configured to use it as a compile-time dependency.
+ //
+ // We try to load all functions even if some fail so that we get the debug log
+ // unconditionally.
+# define CUPS_SHIM_LOAD(opt_, fn_) \
+ success |= \
+ LoadCupsFunc(mCupsLib, reinterpret_cast<void**>(&fn_), #fn_, opt_);
+ CUPS_SHIM_ALL_FUNCS(CUPS_SHIM_LOAD)
+# undef CUPS_SHIM_LOAD
+
+ if (!success) {
+# ifndef MOZ_TSAN
+ // With TSan, we cannot unload libcups once we have loaded it because
+ // TSan does not support unloading libraries that are matched from its
+ // suppression list. Hence we just keep the library loaded in TSan builds.
+ PR_UnloadLibrary(mCupsLib);
+# endif
+ mCupsLib = nullptr;
+ return;
+ }
+
+ // Set mInitOkay only if all cups functions are loaded successfully.
+ mInitOkay = true;
+}
+
+#endif