set the BSU/ESU escapes when detected in response to queries #1582

src/lib/input.c

@@ -1,3 +1,4 @@
+#include "input.h"
 #include "internal.h"
 #include "notcurses/direct.h"
 #include <poll.h>
@@ -648,8 +649,10 @@ typedef enum {
 } initstates_e;
 
 typedef struct query_state {
-  tinfo* tcache;
-  queried_terminals_e qterm;  // discovered terminal
+  struct tinfo* tcache;
+  // if the terminal unambiguously identifies itself in response to our
+  // queries, use that identification for advanced feature support.
+  queried_terminals_e qterm;
   initstates_e state, stringstate;
   // stringstate is the state at which this string was initialized, and can be
   // one of STATE_XTVERSION1, STATE_XTGETTCAP_TERMNAME1, STATE_TDA1, and STATE_BG1
@@ -658,6 +661,7 @@ typedef struct query_state {
   size_t stridx;        // position to write in string
   uint32_t bg;          // queried default background or 0
   bool xtgettcap_good;  // high when we've received DCS 1
+  bool appsync;         // application-synchronized updates advertised
 } query_state;
 
 static int
@@ -1096,7 +1100,8 @@ err:
   return -1;
 }
 
-int ncinputlayer_init(tinfo* tcache, FILE* infp, queried_terminals_e* detected){
+int ncinputlayer_init(tinfo* tcache, FILE* infp, queried_terminals_e* detected,
+                      unsigned* appsync){
   ncinputlayer* nilayer = &tcache->input;
   setbuffer(infp, NULL, 0);
   nilayer->inputescapes = NULL;
@@ -1122,6 +1127,7 @@ int ncinputlayer_init(tinfo* tcache, FILE* infp, queried_terminals_e* detected){
     }
     tcache->bg_collides_default = inits.bg;
     *detected = inits.qterm;
+    *appsync = inits.appsync;
   }
   return 0;
 }

src/lib/input.h

@@ -0,0 +1,48 @@
+#ifndef NOTCURSES_INPUT
+#define NOTCURSES_INPUT
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// internal header, not installed
+
+#include <stdio.h>
+
+struct tinfo;
+struct termios;
+struct ncinputlayer;
+
+typedef enum {
+    TERMINAL_UNKNOWN,       // no useful information from queries; use termname
+    TERMINAL_LINUX,         // ioctl()s
+    TERMINAL_XTERM,         // XTVERSION == 'XTerm(ver)'
+    TERMINAL_VTE,           // TDA: "~VTE"
+    TERMINAL_KITTY,         // XTGETTCAP['TN'] == 'xterm-kitty'
+    TERMINAL_FOOT,          // TDA: "\EP!|464f4f54\E\\"
+    TERMINAL_MLTERM,        // XTGETTCAP['TN'] == 'mlterm'
+    TERMINAL_WEZTERM,       // XTVERSION == 'WezTerm *'
+    TERMINAL_ALACRITTY,     // can't be detected; match TERM
+    TERMINAL_CONTOUR,       // XTVERSION == 'console *'
+} queried_terminals_e;
+
+// sets up the input layer, building a trie of escape sequences and their
+// nckey equivalents. if we are connected to a tty, this also completes the
+// terminal detection sequence (we ought have already written our initial
+// queries, ideally as early as possible). if we are able to determine the
+// terminal conclusively, it will be written to |detected|. if the terminal
+// advertised support for application-sychronized updates, |appsync| will be
+// non-zero.
+int ncinputlayer_init(struct tinfo* tcache, FILE* infp,
+                      queried_terminals_e* detected, unsigned* appsync);
+
+void ncinputlayer_stop(struct ncinputlayer* nilayer);
+
+// FIXME absorb into ncinputlayer_init()
+int cbreak_mode(int ttyfd, const struct termios* tpreserved);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/lib/internal.h

@@ -1495,18 +1495,6 @@ cellcmp_and_dupfar(egcpool* dampool, nccell* damcell,
   return 1;
 }
 
-// sets up the input layer, building a trie of escape sequences and their
-// nckey equivalents. if we are connected to a tty, this also completes the
-// terminal detection sequence (we ought have already written our initial
-// queries, ideally as early as possible). if we are able to determine the
-// terminal conclusively, it will be written to |detected|.
-int ncinputlayer_init(tinfo* tcache, FILE* infp, queried_terminals_e* detected);
-
-void ncinputlayer_stop(ncinputlayer* nilayer);
-
-// FIXME absorb into ncinputlayer_init()
-int cbreak_mode(int ttyfd, const struct termios* tpreserved);
-
 int set_fd_nonblocking(int fd, unsigned state, unsigned* oldstate);
 
 int get_tty_fd(FILE* ttyfp);

src/lib/termdesc.c

@@ -1,6 +1,7 @@
 #include <fcntl.h>
 #include <ncurses.h> // needed for some definitions, see terminfo(3ncurses)
 #include "internal.h"
+#include "input.h"
 
 // we found Sixel support -- set up the API
 static inline void
@@ -169,6 +170,15 @@ add_smulx_escapes(tinfo* ti, size_t* tablelen, size_t* tableused){
   return 0;
 }
 
+static int
+add_appsync_escapes(tinfo* ti, size_t* tablelen, size_t* tableused){
+  if(grow_esc_table(ti, "\x1bP=1s\x1b\\", ESCAPE_BSU, tablelen, tableused) ||
+     grow_esc_table(ti, "\x1bP=2s\x1b\\", ESCAPE_ESU, tablelen, tableused)){
+    return -1;
+  }
+  return 0;
+}
+
 // Qui si convien lasciare ogne sospetto; ogne viltà convien che qui sia morta.
 static int
 apply_term_heuristics(tinfo* ti, const char* termname, int fd,
@@ -463,8 +473,9 @@ int interrogate_terminfo(tinfo* ti, int fd, const char* termname, unsigned utf8,
       goto err;
     }
   }
+  unsigned appsync_advertised;
   queried_terminals_e detected;
-  if(ncinputlayer_init(ti, stdin, &detected)){
+  if(ncinputlayer_init(ti, stdin, &detected, &appsync_advertised)){
     goto err;
   }
   if(nocbreak){
@@ -475,6 +486,11 @@ int interrogate_terminfo(tinfo* ti, int fd, const char* termname, unsigned utf8,
       }
     }
   }
+  if(appsync_advertised){
+    if(add_appsync_escapes(ti, &tablelen, &tableused)){
+      goto err;
+    }
+  }
   if(apply_term_heuristics(ti, termname, fd, detected, &tablelen, &tableused)){
     ncinputlayer_stop(&ti->input);
     goto err;

src/lib/termdesc.h

@@ -1,5 +1,5 @@
-#ifndef NOTCURSES_TERM
-#define NOTCURSES_TERM
+#ifndef NOTCURSES_TERMDESC
+#define NOTCURSES_TERMDESC
 
 #ifdef __cplusplus
 extern "C" {
@@ -170,21 +170,6 @@ term_supported_styles(const tinfo* ti){
   return ti->supported_styles;
 }
 
-// if the terminal unambiguously identifies itself in response to our
-// queries, go ahead and trust that, overriding TERM.
-typedef enum {
-  TERMINAL_UNKNOWN,       // no useful information from queries; use termname
-  TERMINAL_LINUX,         // ioctl()s
-  TERMINAL_XTERM,         // XTVERSION == 'XTerm(ver)'
-  TERMINAL_VTE,           // TDA: "~VTE"
-  TERMINAL_KITTY,         // XTGETTCAP['TN'] == 'xterm-kitty'
-  TERMINAL_FOOT,          // TDA: "\EP!|464f4f54\E\\"
-  TERMINAL_MLTERM,        // XTGETTCAP['TN'] == 'mlterm'
-  TERMINAL_WEZTERM,       // XTVERSION == 'WezTerm *'
-  TERMINAL_ALACRITTY,     // can't be detected; match TERM
-  TERMINAL_CONTOUR,       // XTVERSION == 'console *'
-} queried_terminals_e;
-
 #ifdef __cplusplus
 }
 #endif