From e7630e045ad3fb654d292e5be5a3af7cfe532c59 Mon Sep 17 00:00:00 2001 From: Greg Ercolano Date: Sun, 18 Dec 2022 13:21:22 -0800 Subject: [PATCH] Added ansi_show_unknown(bool) (default off) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit It may be useful to some to have the terminal emit an error character to show unknown escape sequences. Off by default, unknown escape sequences are silently ignored. If enabled, '¿' is inserted instead. --- FL/Fl_Simple_Terminal.H | 7 ++++++- src/Fl_Simple_Terminal.cxx | 40 +++++++++++++++++++++++++++++++++++--- 2 files changed, 43 insertions(+), 4 deletions(-) diff --git a/FL/Fl_Simple_Terminal.H b/FL/Fl_Simple_Terminal.H index 10ed81bdb..74b012810 100644 --- a/FL/Fl_Simple_Terminal.H +++ b/FL/Fl_Simple_Terminal.H @@ -161,7 +161,6 @@ private: private: int history_lines_; // max lines allowed in screen history bool stay_at_bottom_; // lets scroller chase last line in buffer - bool ansi_; // enables ANSI sequences // scroll management int lines_; // #lines in buffer (optimization: Fl_Text_Buffer slow to calc this) bool scrollaway_; // true when user changed vscroll away from bottom @@ -175,7 +174,10 @@ private: int normal_style_index_; // "normal" style used by "\033[0m" reset sequence int current_style_index_; // current style used for drawing text char current_style_; // current 'style char' (e.g. 'A' = first style entry) + // ANSI escape seq Fl_Escape_Seq escseq; // escape sequence state handler + bool ansi_; // enables ANSI sequences + bool ansi_show_unknown_; // show '¿' for unknown ESC sequences (default: off) // String parsing vars initialized/used by append(), used by handle_backspace() etc. char *ntm_; // new text memory (ntm) - malloc()ed by append() for output text char *ntp_; // new text ptr (ntp) - points into ntm buffer @@ -193,6 +195,8 @@ public: int history_lines() const; void ansi(bool val); bool ansi() const; + void ansi_show_unknown(bool val); + bool ansi_show_unknown() const; void style_table(Fl_Text_Display::Style_Table_Entry *stable, int stable_size, int normal_style_index=0); const Fl_Text_Display::Style_Table_Entry *style_table() const; int style_table_size() const; @@ -234,6 +238,7 @@ protected: void backspace_buffer(unsigned int count); void handle_backspace(); void append_ansi(const char *s, int len); + void unknown_escape(); }; #endif diff --git a/src/Fl_Simple_Terminal.cxx b/src/Fl_Simple_Terminal.cxx index 680b157dd..3f7ade3eb 100644 --- a/src/Fl_Simple_Terminal.cxx +++ b/src/Fl_Simple_Terminal.cxx @@ -287,7 +287,6 @@ void Fl_Simple_Terminal::vscroll_cb(Fl_Widget *w, void *data) { Fl_Simple_Terminal::Fl_Simple_Terminal(int X,int Y,int W,int H,const char *l) : Fl_Text_Display(X,Y,W,H,l) { history_lines_ = 500; // something 'reasonable' stay_at_bottom_ = true; - ansi_ = false; lines_ = 0; // note: lines!=mNBufferLines when lines are wrapping scrollaway_ = false; scrolling_ = false; @@ -312,6 +311,9 @@ Fl_Simple_Terminal::Fl_Simple_Terminal(int X,int Y,int W,int H,const char *l) : normal_style_index_ = builtin_normal_index; current_style_index_ = builtin_normal_index; current_style_ = 'A' + 0; + // ANSI escape seq + ansi_ = false; + ansi_show_unknown_ = false; // Intercept vertical scrolling orig_vscroll_cb_ = mVScrollBar->callback(); orig_vscroll_data_ = mVScrollBar->user_data(); @@ -470,6 +472,23 @@ void Fl_Simple_Terminal::ansi(bool val) { redraw(); } +/** + See if we should show unknown ANSI sequences with '¿' or not. + \see ansi_show_unknown(bool) +*/ +bool Fl_Simple_Terminal::ansi_show_unknown(void) const { + return ansi_show_unknown_; +} + +/** + Enable showing unknown ESC sequences with the '¿' character. + By default this is off, and unknown escape sequences are silently ignored. + \see ansi_show_unknown() +*/ +void Fl_Simple_Terminal::ansi_show_unknown(bool val) { + ansi_show_unknown_ = val; +} + /** Return the current style table being used. @@ -760,6 +779,16 @@ void Fl_Simple_Terminal::handle_backspace() { backspace_buffer(1); } +// Handle unknown esc sequences +void Fl_Simple_Terminal::unknown_escape() { + if ( ansi_show_unknown() ) { + for ( const char *s = "¿"; *s; s++ ) { + *ntp_++ = *s; // emit utf-8 encoded char + *nsp_++ = current_style(); // use current style + } + } +} + /** Handle appending string with ANSI escape sequences, and other 'special' character processing (such as backspaces). @@ -782,6 +811,7 @@ void Fl_Simple_Terminal::append_ansi(const char *s, int len) { if ( escseq.parse_in_progress() ) { // ESC sequence in progress? switch ( escseq.parse(*sp) ) { // parse until completed or fail case Fl_Escape_Seq::fail: // parsing error? + unknown_escape(); escseq.reset(); // ..reset and continue ++sp; continue; @@ -801,10 +831,10 @@ void Fl_Simple_Terminal::append_ansi(const char *s, int len) { case 'J': // ESC[#J switch (val) { case 0: // ESC[0J -- clear to eol - // unsupported + unknown_escape(); break; case 1: // ESC[1J -- clear to sol - // unsupported + unknown_escape(); break; case 2: // ESC[2J -- clear visible screen // NOTE: Currently we clear the /entire screen history/, and @@ -817,6 +847,9 @@ void Fl_Simple_Terminal::append_ansi(const char *s, int len) { ntp_ = ntm_; // clear text contents accumulated so far nsp_ = nsm_; // clear style contents "" break; + default: // all other ESC[#J unsupported + unknown_escape(); + break; } break; // SELECT GRAPHIC RENDITION (SGR) @@ -831,6 +864,7 @@ void Fl_Simple_Terminal::append_ansi(const char *s, int len) { break; // UNSUPPORTED MODES default: + unknown_escape(); break; // unsupported } }