]> git.saurik.com Git - wxWidgets.git/blobdiff - include/wx/log.h
Renamed HasChildren() to IsContainer(), added GetParent() to wxDataViewModel
[wxWidgets.git] / include / wx / log.h
index b067fc95b8a1a83d03164812bd1cecdee8a55a80..41a4b86faeabb6038f3a6d152308237d5ee23ee1 100644 (file)
@@ -70,10 +70,10 @@ typedef unsigned long wxLogLevel;
 // ----------------------------------------------------------------------------
 
 #if wxUSE_GUI
-    class WXDLLIMPEXP_CORE wxTextCtrl;
-    class WXDLLIMPEXP_CORE wxLogFrame;
-    class WXDLLIMPEXP_CORE wxFrame;
-    class WXDLLIMPEXP_CORE wxWindow;
+    class WXDLLIMPEXP_FWD_CORE wxTextCtrl;
+    class WXDLLIMPEXP_FWD_CORE wxLogFrame;
+    class WXDLLIMPEXP_FWD_CORE wxFrame;
+    class WXDLLIMPEXP_FWD_CORE wxWindow;
 #endif // wxUSE_GUI
 
 // ----------------------------------------------------------------------------
@@ -133,7 +133,7 @@ public:
 
     // static sink function - see DoLog() for function to overload in the
     // derived classes
-    static void OnLog(wxLogLevel level, const wxChar *szString, time_t t);
+    static void OnLog(wxLogLevel level, const wxString& szString, time_t t);
 
     // message buffering
 
@@ -181,6 +181,9 @@ public:
     // current is NULL?
     static void DontCreateOnDemand();
 
+    // Make GetActiveTarget() create a new log object again.
+    static void DoCreateOnDemand();
+
     // log the count of repeating messages instead of logging the messages
     // multiple times
     static void SetRepetitionCounting(bool bRepetCounting = true)
@@ -205,10 +208,13 @@ public:
     // get string trace masks
     static const wxArrayString &GetTraceMasks() { return ms_aTraceMasks; }
 
-    // sets the timestamp string: this is used as strftime() format string
-    // for the log targets which add time stamps to the messages - set it
-    // to NULL to disable time stamping completely.
-    static void SetTimestamp(const wxChar *ts) { ms_timestamp = ts; }
+    // sets the time stamp string format: this is used as strftime() format
+    // string for the log targets which add time stamps to the messages; set
+    // it to empty string to disable time stamping completely.
+    static void SetTimestamp(const wxString& ts) { ms_timestamp = ts; }
+
+    // disable time stamping of log messages
+    static void DisableTimestamp() { SetTimestamp(wxEmptyString); }
 
 
     // accessors
@@ -220,13 +226,13 @@ public:
     static wxTraceMask GetTraceMask() { return ms_ulTraceMask; }
 
     // is this trace mask in the list?
-    static bool IsAllowedTraceMask(const wxChar *mask);
+    static bool IsAllowedTraceMask(const wxString& mask);
 
     // return the current loglevel limit
     static wxLogLevel GetLogLevel() { return ms_logLevel; }
 
     // get the current timestamp format string (may be NULL)
-    static const wxChar *GetTimestamp() { return ms_timestamp; }
+    static const wxString& GetTimestamp() { return ms_timestamp; }
 
 
     // helpers
@@ -252,11 +258,48 @@ protected:
 
     // default DoLog() prepends the time stamp and a prefix corresponding
     // to the message to szString and then passes it to DoLogString()
-    virtual void DoLog(wxLogLevel level, const wxChar *szString, time_t t);
+    virtual void DoLog(wxLogLevel level, const wxString& szString, time_t t);
+#if WXWIN_COMPATIBILITY_2_8
+    // these shouldn't be used by new code
+    wxDEPRECATED_BUT_USED_INTERNALLY(
+        virtual void DoLog(wxLogLevel level, const char *szString, time_t t)
+    );
+
+    wxDEPRECATED_BUT_USED_INTERNALLY(
+        virtual void DoLog(wxLogLevel level, const wchar_t *wzString, time_t t)
+    );
+#endif // WXWIN_COMPATIBILITY_2_8
+
+    void LogString(const wxString& szString, time_t t)
+        { DoLogString(szString, t); }
 
     // default DoLogString does nothing but is not pure virtual because if
     // you override DoLog() you might not need it at all
-    virtual void DoLogString(const wxChar *szString, time_t t);
+    virtual void DoLogString(const wxString& szString, time_t t);
+#if WXWIN_COMPATIBILITY_2_8
+    // these shouldn't be used by new code
+    virtual void DoLogString(const char *WXUNUSED(szString),
+                             time_t WXUNUSED(t)) {}
+    virtual void DoLogString(const wchar_t *WXUNUSED(szString),
+                             time_t WXUNUSED(t)) {}
+#endif // WXWIN_COMPATIBILITY_2_8
+
+    // this macro should be used in the derived classes to avoid warnings about
+    // hiding the other DoLog() overloads when overriding DoLog(wxString) --
+    // but don't use it with MSVC which doesn't give this warning but does give
+    // warning when a deprecated function is overridden
+#if WXWIN_COMPATIBILITY_2_8 && !defined(__VISUALC__)
+    #define wxSUPPRESS_DOLOG_HIDE_WARNING()                                   \
+        virtual void DoLog(wxLogLevel, const char *, time_t) { }              \
+        virtual void DoLog(wxLogLevel, const wchar_t *, time_t) { }
+
+    #define wxSUPPRESS_DOLOGSTRING_HIDE_WARNING()                             \
+        virtual void DoLogString(const char *, time_t) { }                    \
+        virtual void DoLogString(const wchar_t *, time_t) { }
+#else
+    #define wxSUPPRESS_DOLOG_HIDE_WARNING()
+    #define wxSUPPRESS_DOLOGSTRING_HIDE_WARNING()
+#endif
 
     // log a line containing the number of times the previous message was
     // repeated
@@ -286,7 +329,7 @@ private:
 
     // format string for strftime(), if NULL, time stamping log messages is
     // disabled
-    static const wxChar *ms_timestamp;
+    static wxString    ms_timestamp;
 
     static wxTraceMask ms_ulTraceMask;   // controls wxLogTrace behaviour
     static wxArrayString ms_aTraceMasks; // more powerful filter for wxLogTrace
@@ -310,8 +353,11 @@ public:
     virtual void Flush();
 
 protected:
-    virtual void DoLog(wxLogLevel level, const wxChar *szString, time_t t);
-    virtual void DoLogString(const wxChar *szString, time_t t);
+    virtual void DoLog(wxLogLevel level, const wxString& szString, time_t t);
+    virtual void DoLogString(const wxString& szString, time_t t);
+
+    wxSUPPRESS_DOLOG_HIDE_WARNING()
+    wxSUPPRESS_DOLOGSTRING_HIDE_WARNING()
 
 private:
     wxString m_str;
@@ -329,7 +375,9 @@ public:
 
 protected:
     // implement sink function
-    virtual void DoLogString(const wxChar *szString, time_t t);
+    virtual void DoLogString(const wxString& szString, time_t t);
+
+    wxSUPPRESS_DOLOGSTRING_HIDE_WARNING()
 
     FILE *m_fp;
 
@@ -347,7 +395,9 @@ public:
 
 protected:
     // implement sink function
-    virtual void DoLogString(const wxChar *szString, time_t t);
+    virtual void DoLogString(const wxString& szString, time_t t);
+
+    wxSUPPRESS_DOLOGSTRING_HIDE_WARNING()
 
     // using ptr here to avoid including <iostream.h> from this file
     wxSTD ostream *m_ostr;
@@ -416,9 +466,14 @@ public:
     // override base class version to flush the old logger as well
     virtual void Flush();
 
+    // call to avoid destroying the old log target
+    void DetachOldLog() { m_logOld = NULL; }
+
 protected:
     // pass the chain to the old logger if needed
-    virtual void DoLog(wxLogLevel level, const wxChar *szString, time_t t);
+    virtual void DoLog(wxLogLevel level, const wxString& szString, time_t t);
+
+    wxSUPPRESS_DOLOG_HIDE_WARNING()
 
 private:
     // the current log target
@@ -434,13 +489,28 @@ private:
 };
 
 // a chain log target which uses itself as the new logger
-class WXDLLIMPEXP_BASE wxLogPassThrough : public wxLogChain
+
+#define wxLogPassThrough wxLogInterposer
+
+class WXDLLIMPEXP_BASE wxLogInterposer : public wxLogChain
 {
 public:
-    wxLogPassThrough();
+    wxLogInterposer();
 
 private:
-    DECLARE_NO_COPY_CLASS(wxLogPassThrough)
+    DECLARE_NO_COPY_CLASS(wxLogInterposer)
+};
+
+// a temporary interposer which doesn't destroy the old log target
+// (calls DetachOldLog)
+
+class WXDLLIMPEXP_BASE wxLogInterposerTemp : public wxLogChain
+{
+public:
+    wxLogInterposerTemp();
+
+private:
+    DECLARE_NO_COPY_CLASS(wxLogInterposerTemp)
 };
 
 #if wxUSE_GUI
@@ -471,38 +541,104 @@ WXDLLIMPEXP_BASE const wxChar* wxSysErrorMsg(unsigned long nErrCode = 0);
 // define wxLog<level>
 // ----------------------------------------------------------------------------
 
-#define DECLARE_LOG_FUNCTION_PUBLIC(level)                                  \
-    /* void wxLog##level(const wxChar *szFormat, ...); */                   \
-    WX_DEFINE_VARARG_FUNC_VOID(wxLog##level, wxDoLog##level)
+#define DECLARE_LOG_FUNCTION(level)                                         \
+    extern void WXDLLIMPEXP_BASE                                            \
+    wxDoLog##level##Wchar(const wxChar *format, ...);                       \
+    extern void WXDLLIMPEXP_BASE                                            \
+    wxDoLog##level##Utf8(const char *format, ...);                          \
+    WX_DEFINE_VARARG_FUNC_VOID(wxLog##level,                                \
+                               1, (const wxFormatString&),                  \
+                               wxDoLog##level##Wchar, wxDoLog##level##Utf8) \
+    DECLARE_LOG_FUNCTION_WATCOM(level)                                      \
+    extern void WXDLLIMPEXP_BASE wxVLog##level(const wxString& format,      \
+                                               va_list argptr)
+
+#ifdef __WATCOMC__
+    // workaround for http://bugzilla.openwatcom.org/show_bug.cgi?id=351;
+    // can't use WX_WATCOM_ONLY_CODE here because the macro would expand to
+    // something too big for Borland C++ to handle
+    #define DECLARE_LOG_FUNCTION_WATCOM(level)                              \
+        WX_VARARG_WATCOM_WORKAROUND(void, wxLog##level,                     \
+                                   1, (const wxString&),                    \
+                                   (wxFormatString(f1)))                    \
+        WX_VARARG_WATCOM_WORKAROUND(void, wxLog##level,                     \
+                                   1, (const wxCStrData&),                  \
+                                   (wxFormatString(f1)))                    \
+        WX_VARARG_WATCOM_WORKAROUND(void, wxLog##level,                     \
+                                   1, (const char*),                        \
+                                   (wxFormatString(f1)))                    \
+        WX_VARARG_WATCOM_WORKAROUND(void, wxLog##level,                     \
+                                   1, (const wchar_t*),                     \
+                                   (wxFormatString(f1)))
+#else
+    #define DECLARE_LOG_FUNCTION_WATCOM(level)
+#endif
 
-#define DECLARE_LOG_FUNCTION_IMPL(level)                                    \
-    extern void WXDLLIMPEXP_BASE wxVLog##level(const wxChar *szFormat,      \
-                                               va_list argptr);             \
-    extern void WXDLLIMPEXP_BASE wxDoLog##level(const wxChar *szFormat,     \
-                                                ...) ATTRIBUTE_PRINTF_1
 
-#define DECLARE_LOG_FUNCTION2_EXP_IMPL(level, argclass, arg, expdecl)       \
+#define DECLARE_LOG_FUNCTION2_EXP(level, argclass, arg, expdecl)            \
+    extern void expdecl wxDoLog##level##Wchar(argclass arg,                 \
+                                              const wxChar *format, ...);   \
+    extern void expdecl wxDoLog##level##Utf8(argclass arg,                  \
+                                             const char *format, ...);      \
+    WX_DEFINE_VARARG_FUNC_VOID(wxLog##level,                                \
+                               2, (argclass, const wxFormatString&),        \
+                               wxDoLog##level##Wchar, wxDoLog##level##Utf8) \
+    DECLARE_LOG_FUNCTION2_EXP_WATCOM(level, argclass, arg, expdecl)         \
     extern void expdecl wxVLog##level(argclass arg,                         \
-                                      const wxChar *szFormat,               \
-                                      va_list argptr);                      \
-    extern void expdecl wxDoLog##level(argclass arg,                        \
-                                       const wxChar *szFormat,              \
-                                       ...) ATTRIBUTE_PRINTF_2
+                                      const wxString& format,               \
+                                      va_list argptr)
+
+#ifdef __WATCOMC__
+    // workaround for http://bugzilla.openwatcom.org/show_bug.cgi?id=351;
+    // can't use WX_WATCOM_ONLY_CODE here because the macro would expand to
+    // something too big for Borland C++ to handle
+    #define DECLARE_LOG_FUNCTION2_EXP_WATCOM(level, argclass, arg, expdecl) \
+        WX_VARARG_WATCOM_WORKAROUND(void, wxLog##level,                     \
+                                   2, (argclass, const wxString&),          \
+                                   (f1, wxFormatString(f2)))                \
+        WX_VARARG_WATCOM_WORKAROUND(void, wxLog##level,                     \
+                                   2, (argclass, const wxCStrData&),        \
+                                   (f1, wxFormatString(f2)))                \
+        WX_VARARG_WATCOM_WORKAROUND(void, wxLog##level,                     \
+                                   2, (argclass, const char*),              \
+                                   (f1, wxFormatString(f2)))                \
+        WX_VARARG_WATCOM_WORKAROUND(void, wxLog##level,                     \
+                                   2, (argclass, const wchar_t*),           \
+                                   (f1, wxFormatString(f2)))
+#else
+    #define DECLARE_LOG_FUNCTION2_EXP_WATCOM(level, argclass, arg, expdecl)
+#endif
+
 
 #else // !wxUSE_LOG
 
-// log functions do nothing at all
-#define DECLARE_LOG_FUNCTION_PUBLIC(level)                                  \
-    /* void wxLog##level(const wxChar *szFormat, ...) {} */                 \
-    WX_DEFINE_VARARG_FUNC_NOP(wxLog##level)
+#ifdef __WATCOMC__
+    // workaround for http://bugzilla.openwatcom.org/show_bug.cgi?id=351
+    #define WX_WATCOM_ONLY_CODE( x )  x
+#else
+    #define WX_WATCOM_ONLY_CODE( x )
+#endif
 
-#define DECLARE_LOG_FUNCTION_IMPL(level)                                    \
-    inline void wxVLog##level(const wxChar *WXUNUSED(szFormat),             \
+// log functions do nothing at all
+#define DECLARE_LOG_FUNCTION(level)                                         \
+    WX_DEFINE_VARARG_FUNC_NOP(wxLog##level, 1, (const wxString&))           \
+    WX_WATCOM_ONLY_CODE(                                                    \
+        WX_DEFINE_VARARG_FUNC_NOP(wxLog##level, 1, (const char*))           \
+        WX_DEFINE_VARARG_FUNC_NOP(wxLog##level, 1, (const wchar_t*))        \
+        WX_DEFINE_VARARG_FUNC_NOP(wxLog##level, 1, (const wxCStrData&))     \
+    )                                                                       \
+    inline void wxVLog##level(const wxString& WXUNUSED(format),             \
                               va_list WXUNUSED(argptr)) { }                 \
 
-#define DECLARE_LOG_FUNCTION2_EXP_IMPL(level, argclass, arg, expdecl)       \
+#define DECLARE_LOG_FUNCTION2_EXP(level, argclass, arg, expdecl)            \
+    WX_DEFINE_VARARG_FUNC_NOP(wxLog##level, 2, (argclass, const wxString&)) \
+    WX_WATCOM_ONLY_CODE(                                                    \
+        WX_DEFINE_VARARG_FUNC_NOP(wxLog##level, 2, (argclass, const char*)) \
+        WX_DEFINE_VARARG_FUNC_NOP(wxLog##level, 2, (argclass, const wchar_t*)) \
+        WX_DEFINE_VARARG_FUNC_NOP(wxLog##level, 2, (argclass, const wxCStrData&)) \
+    )                                                                       \
     inline void wxVLog##level(argclass WXUNUSED(arg),                       \
-                              const wxChar *WXUNUSED(szFormat),             \
+                              const wxString& WXUNUSED(format),             \
                               va_list WXUNUSED(argptr)) {}
 
 // Empty Class to fake wxLogNull
@@ -521,24 +657,15 @@ public:
 
 #endif // wxUSE_LOG/!wxUSE_LOG
 
-#define DECLARE_LOG_FUNCTION(level)                                         \
-    DECLARE_LOG_FUNCTION_PUBLIC(level)                                      \
-    DECLARE_LOG_FUNCTION_IMPL(level)
-
-#define DECLARE_LOG_FUNCTION2_EXP(level, argclass, arg, expdecl)            \
-    DECLARE_LOG_FUNCTION_PUBLIC(level)                                      \
-    DECLARE_LOG_FUNCTION2_EXP_IMPL(level, argclass, arg, expdecl)
-
-#define DECLARE_LOG_FUNCTION2_EXP(level, argclass, arg, expdecl)            \
-    DECLARE_LOG_FUNCTION_PUBLIC(level)                                      \
-    DECLARE_LOG_FUNCTION2_EXP_IMPL(level, argclass, arg, expdecl)
-
-#define DECLARE_LOG_FUNCTION2_IMPL(level, argclass, arg)                    \
-    DECLARE_LOG_FUNCTION2_EXP_IMPL(level, argclass, arg, WXDLLIMPEXP_BASE)
-
 #define DECLARE_LOG_FUNCTION2(level, argclass, arg)                         \
     DECLARE_LOG_FUNCTION2_EXP(level, argclass, arg, WXDLLIMPEXP_BASE)
 
+// VC6 produces a warning if we a macro expanding to nothing to
+// DECLARE_LOG_FUNCTION2:
+#if defined(__VISUALC__) && __VISUALC__ < 1300
+    // "not enough actual parameters for macro 'DECLARE_LOG_FUNCTION2_EXP'"
+    #pragma warning(disable:4003)
+#endif
 
 // a generic function for all levels (level is passes as parameter)
 DECLARE_LOG_FUNCTION2(Generic, wxLogLevel, level);
@@ -553,26 +680,26 @@ DECLARE_LOG_FUNCTION(Verbose);
 
 // this function sends the log message to the status line of the top level
 // application frame, if any
-DECLARE_LOG_FUNCTION_IMPL(Status);
+DECLARE_LOG_FUNCTION(Status);
 
 #if wxUSE_GUI
     // this one is the same as previous except that it allows to explicitly
-    class WXDLLEXPORT wxFrame;
+    class WXDLLIMPEXP_FWD_CORE wxFrame;
     // specify the frame to which the output should go
-    DECLARE_LOG_FUNCTION2_EXP_IMPL(Status, wxFrame *, pFrame, WXDLLIMPEXP_CORE);
+    DECLARE_LOG_FUNCTION2_EXP(Status, wxFrame *, pFrame, WXDLLIMPEXP_CORE);
 #endif // wxUSE_GUI
 
-DECLARE_LOG_FUNCTION_PUBLIC(Status)
-
 // additional one: as wxLogError, but also logs last system call error code
 // and the corresponding error message if available
-DECLARE_LOG_FUNCTION_IMPL(SysError);
+DECLARE_LOG_FUNCTION(SysError);
 
 // and another one which also takes the error code (for those broken APIs
 // that don't set the errno (like registry APIs in Win32))
-DECLARE_LOG_FUNCTION2_IMPL(SysError, long, lErrCode);
-
-DECLARE_LOG_FUNCTION_PUBLIC(SysError)
+DECLARE_LOG_FUNCTION2(SysError, long, lErrCode);
+#ifdef __WATCOMC__
+// workaround for http://bugzilla.openwatcom.org/show_bug.cgi?id=351
+DECLARE_LOG_FUNCTION2(SysError, unsigned long, lErrCode);
+#endif
 
 // debug functions do nothing in release mode
 #if wxUSE_LOG && wxUSE_LOG_DEBUG
@@ -584,12 +711,21 @@ DECLARE_LOG_FUNCTION_PUBLIC(SysError)
 
     // this version only logs the message if the mask had been added to the
     // list of masks with AddTraceMask()
-    DECLARE_LOG_FUNCTION2_IMPL(Trace, const wxChar*, mask);
+    DECLARE_LOG_FUNCTION2(Trace, const wxString&, mask);
+#ifdef __WATCOMC__
+    // workaround for http://bugzilla.openwatcom.org/show_bug.cgi?id=351
+    DECLARE_LOG_FUNCTION2(Trace, const char*, mask);
+    DECLARE_LOG_FUNCTION2(Trace, const wchar_t*, mask);
+#endif
+
     // and this one does nothing if all of level bits are not set in
     // wxLog::GetActive()->GetTraceMask() -- it's deprecated in favour of
     // string identifiers
-    DECLARE_LOG_FUNCTION2_IMPL(Trace, wxTraceMask, mask);
-    DECLARE_LOG_FUNCTION_PUBLIC(Trace)
+    DECLARE_LOG_FUNCTION2(Trace, wxTraceMask, mask);
+#ifdef __WATCOMC__
+    // workaround for http://bugzilla.openwatcom.org/show_bug.cgi?id=351
+    DECLARE_LOG_FUNCTION2(Trace, int, mask);
+#endif
 #else   //!debug || !wxUSE_LOG
     // these functions do nothing in release builds, but don't define them as
     // nothing as it could result in different code structure in debug and
@@ -613,13 +749,23 @@ DECLARE_LOG_FUNCTION_PUBLIC(SysError)
         #define wxLogTrace(mask, fmt, ...) wxLogNop()
     #else // !HAVE_VARIADIC_MACROS
         //inline void wxLogDebug(const wxString& fmt, ...) {}
-        WX_DEFINE_VARARG_FUNC_NOP(wxLogDebug)
+        WX_DEFINE_VARARG_FUNC_NOP(wxLogDebug, 1, (const wxString&))
         //inline void wxLogTrace(wxTraceMask, const wxString& fmt, ...) {}
         //inline void wxLogTrace(const wxString&, const wxString& fmt, ...) {}
-        WX_DEFINE_VARARG_FUNC_NOP(wxLogTrace)
+        WX_DEFINE_VARARG_FUNC_NOP(wxLogTrace, 2, (wxTraceMask, const wxString&))
+        WX_DEFINE_VARARG_FUNC_NOP(wxLogTrace, 2, (const wxString&, const wxString&))
+        #ifdef __WATCOMC__
+        // workaround for http://bugzilla.openwatcom.org/show_bug.cgi?id=351
+        WX_DEFINE_VARARG_FUNC_NOP(wxLogTrace, 2, (const char*, const char*))
+        WX_DEFINE_VARARG_FUNC_NOP(wxLogTrace, 2, (const wchar_t*, const wchar_t*))
+        #endif
     #endif // HAVE_VARIADIC_MACROS/!HAVE_VARIADIC_MACROS
 #endif // debug/!debug
 
+#if defined(__VISUALC__) && __VISUALC__ < 1300
+    #pragma warning(default:4003)
+#endif
+
 // wxLogFatalError helper: show the (fatal) error to the user in a safe way,
 // i.e. without using wxMessageBox() for example because it could crash
 void WXDLLIMPEXP_BASE
@@ -635,13 +781,13 @@ wxSafeShowMessage(const wxString& title, const wxString& text);
 #ifdef __VISUALC__
     #define wxLogApiError(api, rc)                                            \
         wxLogDebug(wxT("%s(%d): '%s' failed with error 0x%08lx (%s)."),       \
-                   __TFILE__, __LINE__, api,                                  \
+                   __FILE__, __LINE__, api,                                   \
                    (long)rc, wxSysErrorMsg(rc))
 #else // !VC++
     #define wxLogApiError(api, rc)                                            \
         wxLogDebug(wxT("In file %s at line %d: '%s' failed with ")            \
                    wxT("error 0x%08lx (%s)."),                                \
-                   __TFILE__, __LINE__, api,                                  \
+                   __FILE__, __LINE__, api,                                   \
                    (long)rc, wxSysErrorMsg(rc))
 #endif // VC++/!VC++
 
@@ -657,5 +803,9 @@ wxSafeShowMessage(const wxString& title, const wxString& text);
 #include "wx/cocoa/log.h"
 #endif
 
+#ifdef WX_WATCOM_ONLY_CODE
+    #undef WX_WATCOM_ONLY_CODE
+#endif
+
 #endif  // _WX_LOG_H_