Merge pull request #8818 from rouault/coverity_fixes

Coverity fixes
OSGeo · Nov 25, 2023 · 80e5e39 · 80e5e39
2 parents d430aff + 5d99523
commit 80e5e39
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Showing 3 changed files with 26 additions and 4 deletions.
diff --git a/frmts/pdf/pdfdataset.cpp b/frmts/pdf/pdfdataset.cpp
@@ -1258,6 +1258,11 @@ static int LoadPdfiumDocumentPage(const char *pszFilename,
         }
         auto pPage = pdfium::MakeRetain<CPDF_Page>(
             poDoc->doc,
+            // coverity is confused by WrapRetain(), believing that multiple
+            // smart pointers manage the same raw pointer. Which is actually
+            // true, but a RetainPtr holds a reference counted object. It is
+            // thus safe to have several RetainPtr holding it.
+            // coverity[multiple_init_smart_ptr]
             pdfium::WrapRetain(const_cast<CPDF_Dictionary *>(pDict.Get())));
 
         poPage = new TPdfiumPageStruct;
@@ -2537,6 +2542,11 @@ GDALPDFObject *PDFDataset::GetCatalog()
         const CPDF_Dictionary *catalog = m_poDocPdfium->doc->GetRoot();
         if (catalog)
             m_poCatalogObject =
+                // coverity is confused by WrapRetain(), believing that multiple
+                // smart pointers manage the same raw pointer. Which is actually
+                // true, but a RetainPtr holds a reference counted object. It is
+                // thus safe to have several RetainPtr holding it.
+                // coverity[multiple_init_smart_ptr]
                 GDALPDFObjectPdfium::Build(pdfium::WrapRetain(catalog));
     }
 #endif  // ~ HAVE_PDFIUM
@@ -5401,6 +5411,11 @@ PDFDataset *PDFDataset::Open(GDALOpenInfo *poOpenInfo)
     if (bUseLib.test(PDFLIB_PDFIUM))
     {
         GDALPDFObjectPdfium *poRoot = GDALPDFObjectPdfium::Build(
+            // coverity is confused by WrapRetain(), believing that multiple
+            // smart pointers manage the same raw pointer. Which is actually
+            // true, but a RetainPtr holds a reference counted object. It is
+            // thus safe to have several RetainPtr holding it.
+            // coverity[multiple_init_smart_ptr]
             pdfium::WrapRetain(poDocPdfium->doc->GetRoot()));
         if (poRoot->GetType() == PDFObjectType_Dictionary)
         {

diff --git a/ogr/swq.cpp b/ogr/swq.cpp
@@ -321,8 +321,6 @@ const char *swq_select_summarize(swq_select *select_info, int dest_column,
                                  const char *value)
 
 {
-    swq_col_def *def = &select_info->column_defs[dest_column];
-
     /* -------------------------------------------------------------------- */
     /*      Do various checking.                                            */
     /* -------------------------------------------------------------------- */
@@ -333,6 +331,7 @@ const char *swq_select_summarize(swq_select *select_info, int dest_column,
         dest_column >= static_cast<int>(select_info->column_defs.size()))
         return "dest_column out of range in swq_select_summarize().";
 
+    swq_col_def *def = &select_info->column_defs[dest_column];
     if (def->col_func == SWQCF_NONE && !def->distinct_flag)
         return nullptr;
 

diff --git a/port/cpl_vsil_gzip.cpp b/port/cpl_vsil_gzip.cpp
@@ -2454,15 +2454,23 @@ size_t VSIGZipWriteHandleMT::Write(const void *const pBuffer,
         {
             while (true)
             {
+                // We store in a local variable instead of pCurBuffer_ directly
+                // to avoid Coverity Scan to be confused by the fact that we
+                // have used above pCurBuffer_ outside of the mutex. But what
+                // is protected by the mutex is aposBuffers_, not pCurBuffer_.
+                std::string *l_pCurBuffer = nullptr;
                 {
                     std::lock_guard<std::mutex> oLock(sMutex_);
                     if (!aposBuffers_.empty())
                     {
-                        pCurBuffer_ = aposBuffers_.back();
+                        l_pCurBuffer = aposBuffers_.back();
                         aposBuffers_.pop_back();
-                        break;
                     }
                 }
+                pCurBuffer_ = l_pCurBuffer;
+                if (pCurBuffer_)
+                    break;
+
                 if (poPool_)
                 {
                     poPool_->WaitEvent();