Avoid -Werror=format-{overflow,truncation}=

...as emitted by at least GCC 8.2 with --enable-optimized, by making the buffers
large enough for the (hypothetical) largest values of the various date/time
components

Reviewed-on: https://gerrit.libreoffice.org/66618
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
(cherry picked from commit 113536e974d7ebbbc484b0ef40406f9b4d14e511)

Change-Id: I82e9b08fa099546b2d6f29c702e1440df9e6c6e0

2 files changed, 12 insertions, 10 deletions

diff --git a/connectivity/source/drivers/dbase/DTable.cxx b/connectivity/source/drivers/dbase/DTable.cxx
index 22d9f441b1f0..80fbebc6d608 100644
--- a/connectivity/source/drivers/dbase/DTable.cxx
+++ b/connectivity/source/drivers/dbase/DTable.cxx
@@ -1827,16 +1827,17 @@ bool ODbaseTable::UpdateBuffer(OValueRefVector& rRow, const OValueRefRow& pOrgRo
                         aDate = ::dbtools::DBTypeConversion::toDate(thisColVal.getDouble());
                     else
                         aDate = thisColVal;
-                    char s[9];
+                    char s[sizeof("-327686553565535")];
+                        // reserve enough space for hypothetical max length
                     snprintf(s,
                         sizeof(s),
                         "%04d%02d%02d",
-                        (int)aDate.Year,
-                        (int)aDate.Month,
-                        (int)aDate.Day);
+                        static_cast<sal_Int32>(aDate.Year),
+                        static_cast<sal_uInt32>(aDate.Month),
+                        static_cast<sal_uInt32>(aDate.Day));
 
-                    // Exactly 8 bytes to copy:
-                    strncpy(pData,s,sizeof s - 1);
+                    // Exactly 8 bytes to copy (even if s could hypothetically be longer):
+                    memcpy(pData,s,8);
                 } break;
                 case DataType::INTEGER:
                     {
diff --git a/connectivity/source/drivers/jdbc/ConnectionLog.cxx b/connectivity/source/drivers/jdbc/ConnectionLog.cxx
index 3218c0dc2bdc..a8abf0d82e8a 100644
--- a/connectivity/source/drivers/jdbc/ConnectionLog.cxx
+++ b/connectivity/source/drivers/jdbc/ConnectionLog.cxx
@@ -98,11 +98,12 @@ namespace comphelper { namespace log { namespace convert
 
     OUString convertLogArgToString( const DateTime& _rDateTime )
     {
-        char buffer[ 30 ];
+        char buffer[ sizeof("-32768-65535-65535 65535:65535:65535.4294967295") ];
+            // reserve enough space for hypothetical max length
         const size_t buffer_size = sizeof( buffer );
-        snprintf( buffer, buffer_size, "%04i-%02i-%02i %02i:%02i:%02i.%09i",
-            (int)_rDateTime.Year, (int)_rDateTime.Month, (int)_rDateTime.Day,
-            (int)_rDateTime.Hours, (int)_rDateTime.Minutes, (int)_rDateTime.Seconds, (int)_rDateTime.NanoSeconds );
+        snprintf( buffer, buffer_size, "%04" SAL_PRIdINT32 "-%02" SAL_PRIuUINT32 "-%02" SAL_PRIuUINT32 " %02" SAL_PRIuUINT32 ":%02" SAL_PRIuUINT32 ":%02" SAL_PRIuUINT32 ".%09" SAL_PRIuUINT32,
+            static_cast<sal_Int32>(_rDateTime.Year), static_cast<sal_uInt32>(_rDateTime.Month), static_cast<sal_uInt32>(_rDateTime.Day),
+            static_cast<sal_uInt32>(_rDateTime.Hours), static_cast<sal_uInt32>(_rDateTime.Minutes), static_cast<sal_uInt32>(_rDateTime.Seconds), _rDateTime.NanoSeconds );
         return OUString::createFromAscii( buffer );
     }