Consolidate Unix and Windows implementations of QHostInfo::fromName

The implementations were practically identical, so we can just move the
code into qhostinfo.cpp, cleaning up things along the way.

Since QHostInfoAgent is an internal class, add the shared code as
additional static helper functions. And since half the code already used
QCoreApplication::translate anyway, we can remove the QObject
inheritance which was only added for getting a tr().

Change-Id: I58eafbdc3e7d06d2e898486a1add63cd63d98c96
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 168 insertions, 0 deletions

diff --git a/src/network/kernel/qhostinfo.cpp b/src/network/kernel/qhostinfo.cpp
index d3fe85f5d5..9374728244 100644
--- a/src/network/kernel/qhostinfo.cpp
+++ b/src/network/kernel/qhostinfo.cpp
@@ -37,8 +37,11 @@
 **
 ****************************************************************************/
 
+//#define QHOSTINFO_DEBUG
+
 #include "qhostinfo.h"
 #include "qhostinfo_p.h"
+#include <qplatformdefs.h>
 
 #include "QtCore/qscopedpointer.h"
 #include <qabstracteventdispatcher.h>
@@ -53,6 +56,15 @@
 
 #ifdef Q_OS_UNIX
 #  include <unistd.h>
+#  include <netdb.h>
+#  include <netinet/in.h>
+#  if defined(AI_ADDRCONFIG)
+#    define Q_ADDRCONFIG          AI_ADDRCONFIG
+#  endif
+#elif defined Q_OS_WIN
+#  include <ws2tcpip.h>
+
+#  define QT_SOCKLEN_T int
 #endif
 
 QT_BEGIN_NAMESPACE
@@ -412,6 +424,162 @@ QHostInfo QHostInfoAgent::fromName(const QString &hostName, QSharedPointer<QNetw
 }
 #endif
 
+QHostInfo QHostInfoAgent::reverseLookup(const QHostAddress &address)
+{
+    QHostInfo results;
+    // Reverse lookup
+    sockaddr_in sa4;
+    sockaddr_in6 sa6;
+    sockaddr *sa = 0;
+    QT_SOCKLEN_T saSize;
+    if (address.protocol() == QAbstractSocket::IPv4Protocol) {
+        sa = reinterpret_cast<sockaddr *>(&sa4);
+        saSize = sizeof(sa4);
+        memset(&sa4, 0, sizeof(sa4));
+        sa4.sin_family = AF_INET;
+        sa4.sin_addr.s_addr = htonl(address.toIPv4Address());
+    } else {
+        sa = reinterpret_cast<sockaddr *>(&sa6);
+        saSize = sizeof(sa6);
+        memset(&sa6, 0, sizeof(sa6));
+        sa6.sin6_family = AF_INET6;
+        memcpy(&sa6.sin6_addr, address.toIPv6Address().c, sizeof(sa6.sin6_addr));
+    }
+
+    char hbuf[NI_MAXHOST];
+    if (sa && getnameinfo(sa, saSize, hbuf, sizeof(hbuf), nullptr, 0, 0) == 0)
+        results.setHostName(QString::fromLatin1(hbuf));
+
+    if (results.hostName().isEmpty())
+        results.setHostName(address.toString());
+    results.setAddresses(QList<QHostAddress>() << address);
+
+    return results;
+}
+
+/*
+    Call getaddrinfo, and returns the results as QHostInfo::addresses
+*/
+QHostInfo QHostInfoAgent::lookup(const QString &hostName)
+{
+    QHostInfo results;
+
+    // IDN support
+    QByteArray aceHostname = QUrl::toAce(hostName);
+    results.setHostName(hostName);
+    if (aceHostname.isEmpty()) {
+        results.setError(QHostInfo::HostNotFound);
+        results.setErrorString(hostName.isEmpty() ?
+                               QCoreApplication::translate("QHostInfoAgent", "No host name given") :
+                               QCoreApplication::translate("QHostInfoAgent", "Invalid hostname"));
+        return results;
+    }
+
+    addrinfo *res = 0;
+    struct addrinfo hints;
+    memset(&hints, 0, sizeof(hints));
+    hints.ai_family = PF_UNSPEC;
+#ifdef Q_ADDRCONFIG
+    hints.ai_flags = Q_ADDRCONFIG;
+#endif
+
+    int result = getaddrinfo(aceHostname.constData(), nullptr, &hints, &res);
+# ifdef Q_ADDRCONFIG
+    if (result == EAI_BADFLAGS) {
+        // if the lookup failed with AI_ADDRCONFIG set, try again without it
+        hints.ai_flags = 0;
+        result = getaddrinfo(aceHostname.constData(), nullptr, &hints, &res);
+    }
+# endif
+
+    if (result == 0) {
+        addrinfo *node = res;
+        QList<QHostAddress> addresses;
+        while (node) {
+#ifdef QHOSTINFO_DEBUG
+            qDebug() << "getaddrinfo node: flags:" << node->ai_flags << "family:" << node->ai_family
+                     << "ai_socktype:" << node->ai_socktype << "ai_protocol:" << node->ai_protocol
+                     << "ai_addrlen:" << node->ai_addrlen;
+#endif
+            switch (node->ai_family) {
+            case AF_INET: {
+                QHostAddress addr;
+                addr.setAddress(ntohl(((sockaddr_in *) node->ai_addr)->sin_addr.s_addr));
+                if (!addresses.contains(addr))
+                    addresses.append(addr);
+                break;
+            }
+            case AF_INET6: {
+                QHostAddress addr;
+                sockaddr_in6 *sa6 = (sockaddr_in6 *) node->ai_addr;
+                addr.setAddress(sa6->sin6_addr.s6_addr);
+                if (sa6->sin6_scope_id)
+                    addr.setScopeId(QString::number(sa6->sin6_scope_id));
+                if (!addresses.contains(addr))
+                    addresses.append(addr);
+                break;
+            }
+            default:
+                results.setError(QHostInfo::UnknownError);
+                results.setErrorString(QCoreApplication::translate("QHostInfoAgent", "Unknown address type"));
+            }
+            node = node->ai_next;
+        }
+        if (addresses.isEmpty()) {
+            // Reached the end of the list, but no addresses were found; this
+            // means the list contains one or more unknown address types.
+            results.setError(QHostInfo::UnknownError);
+            results.setErrorString(QCoreApplication::translate("QHostInfoAgent", "Unknown address type"));
+        }
+
+        results.setAddresses(addresses);
+        freeaddrinfo(res);
+    } else {
+        switch (result) {
+#ifdef Q_OS_WIN
+        case WSAHOST_NOT_FOUND: //authoritative not found
+        case WSATRY_AGAIN: //non authoritative not found
+        case WSANO_DATA: //valid name, no associated address
+#else
+        case EAI_NONAME:
+        case EAI_FAIL:
+#  ifdef EAI_NODATA // EAI_NODATA is deprecated in RFC 3493
+        case EAI_NODATA:
+#  endif
+#endif
+            results.setError(QHostInfo::HostNotFound);
+            results.setErrorString(QCoreApplication::translate("QHostInfoAgent", "Host not found"));
+            break;
+        default:
+            results.setError(QHostInfo::UnknownError);
+#ifdef Q_OS_WIN
+            results.setErrorString(QString::fromWCharArray(gai_strerror(result)));
+#else
+            results.setErrorString(QString::fromLocal8Bit(gai_strerror(result)));
+#endif
+            break;
+        }
+    }
+
+#if defined(QHOSTINFO_DEBUG)
+    if (results.error() != QHostInfo::NoError) {
+        qDebug("QHostInfoAgent::fromName(): error #%d %s",
+               h_errno, results.errorString().toLatin1().constData());
+    } else {
+        QString tmp;
+        QList<QHostAddress> addresses = results.addresses();
+        for (int i = 0; i < addresses.count(); ++i) {
+            if (i != 0) tmp += QLatin1String(", ");
+            tmp += addresses.at(i).toString();
+        }
+        qDebug("QHostInfoAgent::fromName(): found %i entries for \"%s\": {%s}",
+               addresses.count(), aceHostname.constData(),
+               tmp.toLatin1().constData());
+    }
+#endif
+
+    return results;
+}
 
 /*!
     \enum QHostInfo::HostInfoError