CPLErrorStateBackuper: restore error count, and allow specifying the …

…error handler as CPLQuietErrorHandler is used > 95% of time combined with it
as18g13 · Apr 6, 2024 · be71b41 · be71b41
1 parent f3432cf
commit be71b41
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Showing 2 changed files with 79 additions and 29 deletions.
diff --git a/port/cpl_error.cpp b/port/cpl_error.cpp
@@ -845,17 +845,8 @@ void CPL_STDCALL CPLErrorReset()
  *                       CPLErrorSetState()
  **********************************************************************/
 
-/**
- * Restore an error state, without emitting an error.
- *
- * Can be useful if a routine might call CPLErrorReset() and one wants to
- * preserve the previous error state.
- *
- * @since GDAL 2.0
- */
-
-void CPL_DLL CPLErrorSetState(CPLErr eErrClass, CPLErrorNum err_no,
-                              const char *pszMsg)
+static void CPLErrorSetState(CPLErr eErrClass, CPLErrorNum err_no,
+                             const char *pszMsg, GUInt32 *pnErrorCounter)
 {
     CPLErrorContext *psCtx = CPLGetErrorContext();
     if (psCtx == nullptr)
@@ -891,6 +882,23 @@ void CPL_DLL CPLErrorSetState(CPLErr eErrClass, CPLErrorNum err_no,
     memcpy(pszLastErrMsg, pszMsg, size);
     pszLastErrMsg[size] = '\0';
     psCtx->eLastErrType = eErrClass;
+    if (pnErrorCounter)
+        psCtx->nErrorCounter = *pnErrorCounter;
+}
+
+/**
+ * Restore an error state, without emitting an error.
+ *
+ * Can be useful if a routine might call CPLErrorReset() and one wants to
+ * preserve the previous error state.
+ *
+ * @since GDAL 2.0
+ */
+
+void CPL_DLL CPLErrorSetState(CPLErr eErrClass, CPLErrorNum err_no,
+                              const char *pszMsg)
+{
+    CPLErrorSetState(eErrClass, err_no, pszMsg, nullptr);
 }
 
 /**********************************************************************
@@ -1563,3 +1571,28 @@ void CPLUninstallErrorHandlerAccumulator()
 {
     CPLPopErrorHandler();
 }
+
+/************************************************************************/
+/*               CPLErrorStateBackuper::CPLErrorStateBackuper()         */
+/************************************************************************/
+
+CPLErrorStateBackuper::CPLErrorStateBackuper(CPLErrorHandler hHandler)
+    : m_nLastErrorNum(CPLGetLastErrorNo()),
+      m_nLastErrorType(CPLGetLastErrorType()),
+      m_osLastErrorMsg(CPLGetLastErrorMsg()),
+      m_nLastErrorCounter(CPLGetErrorCounter()),
+      m_poErrorHandlerPusher(
+          hHandler ? std::make_unique<CPLErrorHandlerPusher>(hHandler)
+                   : nullptr)
+{
+}
+
+/************************************************************************/
+/*               CPLErrorStateBackuper::~CPLErrorStateBackuper()        */
+/************************************************************************/
+
+CPLErrorStateBackuper::~CPLErrorStateBackuper()
+{
+    CPLErrorSetState(m_nLastErrorType, m_nLastErrorNum,
+                     m_osLastErrorMsg.c_str(), &m_nLastErrorCounter);
+}
diff --git a/port/cpl_error.h b/port/cpl_error.h
@@ -237,11 +237,13 @@ CPL_C_END
 #define VALIDATE_POINTER_ERR CE_Failure
 #endif
 
-#if defined(__cplusplus) && !defined(CPL_SUPRESS_CPLUSPLUS) &&                 \
-    !defined(DOXYGEN_SKIP)
+/*! @endcond */
+
+#if defined(__cplusplus) && !defined(CPL_SUPRESS_CPLUSPLUS)
 
 extern "C++"
 {
+    /*! @cond Doxygen_Suppress */
     template <class T> T *CPLAssertNotNull(T *x) CPL_RETURNS_NONNULL;
 
     template <class T> T *CPLAssertNotNull(T *x)
@@ -250,58 +252,73 @@ extern "C++"
         return x;
     }
 
+#include <memory>
 #include <string>
 
-    class CPLErrorHandlerPusher
+    /*! @endcond */
+
+    /** Class that installs a (thread-local) error handler on construction, and
+     * restore the initial one on destruction.
+     */
+    class CPL_DLL CPLErrorHandlerPusher
     {
       public:
+        /** Constructor that installs a thread-local temporary error handler
+         * (typically CPLQuietErrorHandler)
+         */
         explicit CPLErrorHandlerPusher(CPLErrorHandler hHandler)
         {
             CPLPushErrorHandler(hHandler);
         }
 
+        /** Constructor that installs a thread-local temporary error handler,
+         * and its user data.
+         */
         CPLErrorHandlerPusher(CPLErrorHandler hHandler, void *user_data)
         {
             CPLPushErrorHandlerEx(hHandler, user_data);
         }
 
+        /** Destructor that restores the initial error handler. */
         ~CPLErrorHandlerPusher()
         {
             CPLPopErrorHandler();
         }
     };
 
-    class CPLErrorStateBackuper
+    /** Class that saves the error state on construction, and
+     * restores it on destruction.
+     */
+    class CPL_DLL CPLErrorStateBackuper
     {
         CPLErrorNum m_nLastErrorNum;
         CPLErr m_nLastErrorType;
         std::string m_osLastErrorMsg;
+        GUInt32 m_nLastErrorCounter;
+        std::unique_ptr<CPLErrorHandlerPusher> m_poErrorHandlerPusher;
 
       public:
-        CPLErrorStateBackuper()
-            : m_nLastErrorNum(CPLGetLastErrorNo()),
-              m_nLastErrorType(CPLGetLastErrorType()),
-              m_osLastErrorMsg(CPLGetLastErrorMsg())
-        {
-        }
-
-        ~CPLErrorStateBackuper()
-        {
-            CPLErrorSetState(m_nLastErrorType, m_nLastErrorNum,
-                             m_osLastErrorMsg.c_str());
-        }
+        /** Constructor that backs up the error state, and optionally installs
+         * a thread-local temporary error handler (typically CPLQuietErrorHandler).
+         */
+        CPLErrorStateBackuper(CPLErrorHandler hHandler = nullptr);
+
+        /** Destructor that restores the error state to its initial state
+         * before construction.
+         */
+        ~CPLErrorStateBackuper();
     };
 }
 
 #ifdef GDAL_COMPILATION
+/*! @cond Doxygen_Suppress */
 // internal only
 bool CPLIsDefaultErrorHandlerAndCatchDebug();
+/*! @endcond */
 #endif
 
 #endif
 
-/*! @endcond */
-
 /** Validate that a pointer is not NULL */
 #define VALIDATE_POINTER0(ptr, func)                                           \
     do                                                                         \