gecko-dev/widget/nsCUPSShim.cpp

77 строки
2.4 KiB
C++

/* -*- 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