From d3faa880d19d9bf5b411dc81c0d5d881a323997d Mon Sep 17 00:00:00 2001 From: Antonio Larrosa Date: Tue, 6 Jun 2017 16:34:32 +0200 Subject: [PATCH] Add remote print queue support Cups servers which announce themselves on avahi will be shown in the printer dialog. This adds a delay the first time the print dialog is opened in order to search for print queues . Because of this delay, the remote print queue discovery is disabled by default and can be enabled by setting the QT_ENABLE_PRINTER_DISCOVERY environment variable to 1. The commit to Qt (which enabled the discovery by default) has a Change-Id: Ib70715d331e8f380a3c9039011bb8521986652aa --- src/plugins/printsupport/cups/qcupsprintengine.cpp | 35 +++++++- .../printsupport/cups/qcupsprintersupport.cpp | 95 ++++++++++++++++++++-- .../printsupport/cups/qcupsprintersupport_p.h | 8 ++ src/plugins/printsupport/cups/qppdprintdevice.cpp | 33 +++++++- 4 files changed, 160 insertions(+), 11 deletions(-) Index: qtbase-everywhere-src-5.10.0/src/plugins/printsupport/cups/qcupsprintengine.cpp =================================================================== --- qtbase-everywhere-src-5.10.0.orig/src/plugins/printsupport/cups/qcupsprintengine.cpp +++ qtbase-everywhere-src-5.10.0/src/plugins/printsupport/cups/qcupsprintengine.cpp @@ -48,6 +48,7 @@ #include #include "private/qcups_p.h" // Only needed for PPK_CupsOptions #include +#include "qcupsprintersupport_p.h" #include @@ -241,8 +242,40 @@ void QCupsPrintEnginePrivate::closePrint // Print the file. cups_option_t* optPtr = cupsOptStruct.size() ? &cupsOptStruct.first() : 0; - cupsPrintFile(printerName.toLocal8Bit().constData(), tempFile.toLocal8Bit().constData(), + + bool fallbackToLocal = false; + cups_dest_t *cupsDest = NULL; + + if (!qEnvironmentVariableIsSet("QT_ENABLE_PRINTER_DISCOVERY")) { + fallbackToLocal = true; + } else { + cupsDest = cupsGetDest(printerName.toLocal8Bit(), NULL, QCupsPrinterSupport::cupsPrintersCount(), QCupsPrinterSupport::cupsPrinters()); + } + + if (cupsDest) { + char resource[HTTP_MAX_URI]; + http_t *http = cupsConnectDest (cupsDest, 0, -1, 0, + resource, sizeof (resource), + 0, 0); + if (http) { + char *name = strrchr (resource, '/'); + qDebug() << "resource:" << resource << "," << name; + if (name) + cupsPrintFile2 (http, ++name, tempFile.toLocal8Bit().constData(), title.toLocal8Bit().constData(), cupsOptStruct.size(), optPtr); + httpClose(http); + } else { + fallbackToLocal=true; + } + } + else { + fallbackToLocal=true; + } + + if (fallbackToLocal) { + cupsPrintFile(printerName.toLocal8Bit().constData(), tempFile.toLocal8Bit().constData(), + title.toLocal8Bit().constData(), cupsOptStruct.size(), optPtr); + } QFile::remove(tempFile); } Index: qtbase-everywhere-src-5.10.0/src/plugins/printsupport/cups/qcupsprintersupport.cpp =================================================================== --- qtbase-everywhere-src-5.10.0.orig/src/plugins/printsupport/cups/qcupsprintersupport.cpp +++ qtbase-everywhere-src-5.10.0/src/plugins/printsupport/cups/qcupsprintersupport.cpp @@ -52,6 +52,35 @@ # include #endif +typedef struct +{ + cups_dest_t *printers; + int num_printers; +} EnumDestsContext; + +static int enum_dest_cb2 (void *user_data, unsigned flags, cups_dest_t *dest) +{ + EnumDestsContext *context = (EnumDestsContext *) user_data; + if ((flags & (CUPS_DEST_FLAGS_UNCONNECTED | + CUPS_DEST_FLAGS_REMOVED | + CUPS_DEST_FLAGS_ERROR | + CUPS_DEST_FLAGS_RESOLVING | + CUPS_DEST_FLAGS_CONNECTING | + CUPS_DEST_FLAGS_CANCELED)) == 0) { + + context->num_printers = cupsCopyDest (dest, context->num_printers, + &context->printers); + + // Also copy whether this is the local default / + cups_dest_t *the_dest; + the_dest = cupsGetDest(dest->name, dest->instance, + context->num_printers, context->printers); + the_dest->is_default = dest->is_default; + qDebug() << dest->name << "_" << dest->instance << "_" << context->num_printers; + } + return 1; +} + QT_BEGIN_NAMESPACE QCupsPrinterSupport::QCupsPrinterSupport() @@ -81,17 +110,35 @@ QPrintDevice QCupsPrinterSupport::create QStringList QCupsPrinterSupport::availablePrintDeviceIds() const { - QStringList list; +/* // Reset cache disabled for now + if (qt_cups_printers) { + cupsFreeDests( qt_cups_num_printers, qt_cups_printers ); + qt_cups_printers = NULL; + qt_cups_num_printers = 0; + } +*/ cups_dest_t *dests; - int count = cupsGetDests(&dests); - list.reserve(count); - for (int i = 0; i < count; ++i) { + bool enablePrinterDiscovery = qEnvironmentVariableIsSet("QT_ENABLE_PRINTER_DISCOVERY"); + if (!enablePrinterDiscovery) { + qt_cups_num_printers = cupsGetDests(&dests); + } else { + if (qt_cups_num_printers == 0) + QCupsPrinterSupport::fillCupsPrinters(); + + dests = qt_cups_printers; + } + QStringList list; + list.reserve(qt_cups_num_printers); + for (int i = 0; i < qt_cups_num_printers; ++i) { QString printerId = QString::fromLocal8Bit(dests[i].name); if (dests[i].instance) printerId += QLatin1Char('/') + QString::fromLocal8Bit(dests[i].instance); list.append(printerId); } - cupsFreeDests(count, dests); + if (!enablePrinterDiscovery) { + cupsFreeDests(qt_cups_num_printers, dests); + } + return list; } @@ -99,8 +146,18 @@ QString QCupsPrinterSupport::defaultPrin { QString printerId; cups_dest_t *dests; - int count = cupsGetDests(&dests); - for (int i = 0; i < count; ++i) { + + bool enablePrinterDiscovery = qEnvironmentVariableIsSet("QT_ENABLE_PRINTER_DISCOVERY"); + if (!enablePrinterDiscovery) { + qt_cups_num_printers = cupsGetDests(&dests); + } else { + if (qt_cups_num_printers == 0) + QCupsPrinterSupport::fillCupsPrinters(); + + dests = qt_cups_printers; + } + + for (int i = 0; i < qt_cups_num_printers; ++i) { if (dests[i].is_default) { printerId = QString::fromLocal8Bit(dests[i].name); if (dests[i].instance) { @@ -109,8 +166,30 @@ QString QCupsPrinterSupport::defaultPrin } } } - cupsFreeDests(count, dests); + if (!enablePrinterDiscovery) { + cupsFreeDests(qt_cups_num_printers, dests); + } return printerId; } +void QCupsPrinterSupport::fillCupsPrinters() +{ + EnumDestsContext context; + context.printers = 0; + context.num_printers = 0; + + qDebug() << "begin enumerating printers"; + + cupsEnumDests(CUPS_DEST_FLAGS_NONE, 4000, NULL, 0, 0, + enum_dest_cb2, &context); + + qDebug() << "end enumerating printers"; + qt_cups_printers = context.printers; + qt_cups_num_printers = context.num_printers; +} + +cups_dest_t *QCupsPrinterSupport::qt_cups_printers = NULL; +int QCupsPrinterSupport::qt_cups_num_printers = 0; + + QT_END_NAMESPACE Index: qtbase-everywhere-src-5.10.0/src/plugins/printsupport/cups/qcupsprintersupport_p.h =================================================================== --- qtbase-everywhere-src-5.10.0.orig/src/plugins/printsupport/cups/qcupsprintersupport_p.h +++ qtbase-everywhere-src-5.10.0/src/plugins/printsupport/cups/qcupsprintersupport_p.h @@ -56,6 +56,8 @@ #include +#include + QT_BEGIN_NAMESPACE class QCupsPrinterSupport : public QPlatformPrinterSupport @@ -71,8 +73,14 @@ public: QStringList availablePrintDeviceIds() const Q_DECL_OVERRIDE; QString defaultPrintDeviceId() const Q_DECL_OVERRIDE; + static void fillCupsPrinters(); + static cups_dest_t *cupsPrinters() { return qt_cups_printers; }; + static int cupsPrintersCount() { return qt_cups_num_printers; }; private: QString cupsOption(int i, const QString &key) const; + + static cups_dest_t *qt_cups_printers; + static int qt_cups_num_printers; }; QT_END_NAMESPACE Index: qtbase-everywhere-src-5.10.0/src/plugins/printsupport/cups/qppdprintdevice.cpp =================================================================== --- qtbase-everywhere-src-5.10.0.orig/src/plugins/printsupport/cups/qppdprintdevice.cpp +++ qtbase-everywhere-src-5.10.0/src/plugins/printsupport/cups/qppdprintdevice.cpp @@ -39,6 +39,7 @@ #include "qppdprintdevice.h" +#include "qcupsprintersupport_p.h" #include #include @@ -451,10 +452,38 @@ void QPpdPrintDevice::loadPrinter() m_cupsDest = 0; } + bool enablePrinterDiscovery = qEnvironmentVariableIsSet("QT_ENABLE_PRINTER_DISCOVERY"); + // Get the print instance and PPD file - m_cupsDest = cupsGetNamedDest(CUPS_HTTP_DEFAULT, m_cupsName, m_cupsInstance); + + if (!enablePrinterDiscovery) { + m_cupsDest = cupsGetNamedDest(CUPS_HTTP_DEFAULT, m_cupsName, m_cupsInstance); + } else { + cups_dest_t *cupsDest = cupsGetDest( m_cupsName, + (m_cupsInstance.isEmpty() ? NULL : m_cupsInstance.data()), + QCupsPrinterSupport::cupsPrintersCount(), + QCupsPrinterSupport::cupsPrinters() ); + cupsCopyDest(cupsDest, 0, &m_cupsDest); + } if (m_cupsDest) { - const char *ppdFile = cupsGetPPD(m_cupsName); + char resource[HTTP_MAX_URI]; + http_t *http = NULL; + const char *ppdFile = NULL; + + if (enablePrinterDiscovery) { + http = cupsConnectDest (m_cupsDest, 0, -1, 0, + resource, sizeof (resource), + 0, 0); + } + if (http) { + char *name = strrchr (resource, '/'); + if (name) + ppdFile = cupsGetPPD2 (http, ++name); + httpClose(http); + } else { + ppdFile = cupsGetPPD(m_cupsName); + } + if (ppdFile) { m_ppd = ppdOpenFile(ppdFile); unlink(ppdFile);