Check the maximum size of a QByteArray more precisely

Also document that the QByteArrray::MaxSize takes a trailing '\0' into
account.

Change-Id: I89e9a0d1a80a49b33efbac16ff7aa2a98f0e5670
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/src/corelib/io/qiodevice.cpp b/src/corelib/io/qiodevice.cpp
index e73a200fb4..d68f33287d 100644
--- a/src/corelib/io/qiodevice.cpp
+++ b/src/corelib/io/qiodevice.cpp
@@ -989,7 +989,7 @@ QByteArray QIODevice::readAll()
         // Size is unknown, read incrementally.
         qint64 readResult;
         do {
-            if (quint64(readBytes) + QIODEVICE_BUFFERSIZE > QByteArray::MaxSize) {
+            if (quint64(readBytes) + QIODEVICE_BUFFERSIZE >= QByteArray::MaxSize) {
                 // If resize would fail, don't read more, return what we have.
                 break;
             }
@@ -1001,7 +1001,7 @@ QByteArray QIODevice::readAll()
     } else {
         // Read it all in one go.
         // If resize fails, don't read anything.
-        if (quint64(readBytes + theSize - d->pos) > QByteArray::MaxSize)
+        if (quint64(readBytes + theSize - d->pos) >= QByteArray::MaxSize)
             return QByteArray();
         result.resize(int(readBytes + theSize - d->pos));
         readBytes += read(result.data() + readBytes, result.size() - readBytes);