[input] add evtype to ncinput, for press/repeat/release #2182

NEWS.md

@@ -12,6 +12,13 @@ rearrangements of Notcurses.
     retrieve terminal messages (if buffers are full, Notcurses cannot
     continue reading). Likewise added `NCDIRECT_OPTION_DRAIN_INPUT`.
   * Removed a bunch of deprecated `static inline` functions from the headers.
+  * A new field, `evtype`, has been added to `ncinput`. It takes a value
+    from among `EVTYPE_{UNKNOWN, PRESS, REPEAT, RELEASE}.`. Where possible,
+    Notcurses will distinguish between a press, repeat, and release. This
+    cannot be done in all environments, nor with all inputs. The
+    `NCKEY_RELEASE` definition is no longer returned; instead, the
+    appropriate `NCKEY_BUTTONx` synthesized key is returned, with
+    `EVTYPE_RELEASE` set.
 
 * 2.4.1 (2021-09-12)
   * `notcurses_check_pixel_support()` still returns 0 if there is no support

USAGE.md

@@ -684,7 +684,12 @@ typedef struct ncinput {
   bool alt;        // was alt held?
   bool shift;      // was shift held?
   bool ctrl;       // was ctrl held?
-  uint64_t seqnum; // input event number
+  enum {
+    EVTYPE_UNKNOWN,
+    EVTYPE_PRESS,
+    EVTYPE_REPEAT,
+    EVTYPE_RELEASE,
+  } evtype;
 } ncinput;
 
 // Read a UTF-32-encoded Unicode codepoint from input. This might only be part

doc/man/man3/notcurses_input.3.md

@@ -21,7 +21,12 @@ typedef struct ncinput {
   bool alt;        // Was Alt held during the event?
   bool shift;      // Was Shift held during the event?
   bool ctrl;       // Was Ctrl held during the event?
-  uint64_t seqnum; // Monotonically increasing input event counter
+  enum {
+    EVTYPE_UNKNOWN,
+    EVTYPE_PRESS,
+    EVTYPE_REPEAT,
+    EVTYPE_RELEASE,
+  } evtype;
 } ncinput;
 ```
 
@@ -77,8 +82,8 @@ be the actual input file descriptor. If it readable, **notcurses_get** can
 be called without the possibility of blocking.
 
 **ncinput_equal_p** compares two **ncinput** structs for data equality (i.e.
-not considering padding or the **seqnum** field), returning **true** if they
-represent the same input (though not necessarily the same input event).
+not considering padding), returning **true** if they represent the same
+input (though not necessarily the same input event).
 
 **notcurses_linesigs_disable** disables conversion of inputs **INTR**, **QUIT**,
 **SUSP**, and **DSUSP** into **SIGINT**, **SIGQUIT**, and **SIGTSTP**. These

include/notcurses/notcurses.h

@@ -1037,19 +1037,25 @@ nckey_mouse_p(uint32_t r){
   return r >= NCKEY_BUTTON1 && r <= NCKEY_RELEASE;
 }
 
-// An input event. Cell coordinates are currently defined only for mouse events.
+// An input event. Cell coordinates are currently defined only for mouse
+// events. It is not guaranteed that we can set the modifiers for a given
+// ncinput. We encompass single Unicode codepoints, not complete EGCs.
 typedef struct ncinput {
-  uint32_t id;     // identifier. Unicode codepoint or synthesized NCKEY event
-  int y;           // y cell coordinate of event, -1 for undefined
-  int x;           // x cell coordinate of event, -1 for undefined
-  bool alt;        // was alt held?
-  bool shift;      // was shift held?
-  bool ctrl;       // was ctrl held?
-  uint64_t seqnum; // input event number
+  uint32_t id;       // Unicode codepoint or synthesized NCKEY event
+  int y;             // y cell coordinate of event, -1 for undefined
+  int x;             // x cell coordinate of event, -1 for undefined
+  bool alt;          // was alt held?
+  bool shift;        // was shift held?
+  bool ctrl;         // was ctrl held?
+  enum {
+    EVTYPE_UNKNOWN,
+    EVTYPE_PRESS,
+    EVTYPE_REPEAT,
+    EVTYPE_RELEASE,
+  } evtype;
 } ncinput;
 
-// compare two ncinput structs for data equality. we can't just use memcmp()
-// due to potential padding in the struct (especially wrt bools) and seqnum.
+// compare two ncinput structs for data equality.
 static inline bool
 ncinput_equal_p(const ncinput* n1, const ncinput* n2){
   if(n1->id != n2->id){
@@ -1061,7 +1067,9 @@ ncinput_equal_p(const ncinput* n1, const ncinput* n2){
   if(n1->alt != n2->alt || n1->shift != n2->shift || n1->ctrl != n2->ctrl){
     return false;
   }
-  // do not check seqnum!
+  if(n1->keytype != n2->keytype){
+    return false;
+  }
   return true;
 }
 

python/examples/006-input-tester.py

@@ -35,7 +35,6 @@ while True:
     std_plane.putstr(f"Is alt: {p.is_alt}", y_pos=3, x_pos=0)
     std_plane.putstr(f"Is shift: {p.is_shift}", y_pos=4, x_pos=0)
     std_plane.putstr(f"Is ctrl: {p.is_ctrl}", y_pos=5, x_pos=0)
-    std_plane.putstr(f"Seqnum: {p.seqnum}", y_pos=6, x_pos=0)
     std_plane.putstr("Press CTRL+C to exit.", y_pos=7, x_pos=0)
 
     std_plane.context.render()

src/lib/in.c

@@ -125,7 +125,6 @@ typedef struct inputctx {
   HANDLE stdinhandle;   // handle to input terminal for MSFT Terminal
 #endif
 
-  uint64_t seqnum;      // process-scope sequence number
   int lmargin, tmargin; // margins in use at left and top
 
   struct esctrie* inputescapes;
@@ -473,7 +472,6 @@ create_inputctx(tinfo* ti, FILE* infp, int lmargin, int tmargin,
                         i->runstring[i->stridx] = '\0';
                         i->lmargin = lmargin;
                         i->tmargin = tmargin;
-                        i->seqnum = 0;
                         i->drain = drain;
                         logdebug("input descriptors: %d/%d\n", i->stdinfd, i->termfd);
                         return i;
@@ -2013,7 +2011,6 @@ internal_get(inputctx* ictx, const struct timespec* ts, ncinput* ni){
   id = ictx->inputs[ictx->iread].id;
   if(ni){
     memcpy(ni, &ictx->inputs[ictx->iread], sizeof(*ni));
-    ni->seqnum = ++ictx->seqnum;
   }
   if(++ictx->iread == ictx->isize){
     ictx->iread = 0;