Add kernel unicode-to-font mappings dynamically for line-drawing characters

src/lib/internal.h

@@ -804,7 +804,7 @@ nc_err_e ncvisual_blit(struct ncvisual* ncv, int rows, int cols,
 
 void nclog(const char* fmt, ...);
 
-bool is_linux_console(const notcurses* nc);
+bool is_linux_console(const notcurses* nc, unsigned no_font_changes);
 
 // get a file descriptor for the controlling tty device, -1 on error
 int get_controlling_tty(void);
@@ -830,6 +830,11 @@ int get_controlling_tty(void);
   if((nc)->loglevel >= NCLOGLEVEL_DEBUG){ \
     nclog("%s:%d:" fmt, __func__, __LINE__, ##__VA_ARGS__); } }while(0);
 
+#define logtrace(nc, fmt, ...) do{ \
+  if((nc)->loglevel >= NCLOGLEVEL_TRACE){ \
+    nclog("%s:%d:" fmt, __func__, __LINE__, ##__VA_ARGS__); } }while(0);
+
+
 // Convert a notcurses log level to some multimedia library equivalent.
 int ffmpeg_log_level(ncloglevel_e level);
 

src/lib/linux.c

@@ -4,19 +4,294 @@
 #include <linux/kd.h>
 #include <sys/ioctl.h>
 
+static unsigned char*
+get_glyph(struct consolefontdesc* cfd, unsigned idx){
+  if(idx >= cfd->charcount){
+    return NULL;
+  }
+  return (unsigned char*)cfd->chardata + 32 * idx;
+}
+
+static int // insert U+2580 (upper half block)
+shim_upper_half_block(struct consolefontdesc* cfd, unsigned idx){
+  unsigned char* glyph = get_glyph(cfd, idx);
+  if(glyph == NULL){
+    return -1;
+  }
+  unsigned r;
+  for(r = 0 ; r < cfd->charheight / 2 ; ++r, ++glyph){
+    *glyph = 0xff;
+  }
+  while(r < cfd->charheight){
+    *glyph = 0;
+    ++glyph;
+    ++r;
+  }
+  return 0;
+}
+
+static int // insert U+2584 (lower half block)
+shim_lower_half_block(struct consolefontdesc* cfd, unsigned idx){
+  unsigned char* glyph = get_glyph(cfd, idx);
+  if(glyph == NULL){
+    return -1;
+  }
+  unsigned r;
+  for(r = 0 ; r < cfd->charheight / 2 ; ++r, ++glyph){
+    *glyph = 0;
+  }
+  while(r < cfd->charheight){
+    *glyph = 0xff;
+    ++glyph;
+    ++r;
+  }
+  return 0;
+}
+
+static int // insert U+258c (left half block)
+shim_left_half_block(struct consolefontdesc* cfd, unsigned idx){
+  unsigned char* glyph = get_glyph(cfd, idx);
+  if(glyph == NULL){
+    return -1;
+  }
+  for(unsigned r = 0 ; r < cfd->charheight ; ++r, ++glyph){
+    *glyph = 0xf0;
+  }
+  return 0;
+}
+
+static int // insert U+2590 (right half block)
+shim_right_half_block(struct consolefontdesc* cfd, unsigned idx){
+  unsigned char* glyph = get_glyph(cfd, idx);
+  if(glyph == NULL){
+    return -1;
+  }
+  for(unsigned r = 0 ; r < cfd->charheight ; ++r, ++glyph){
+    *glyph = 0x0f;
+  }
+  return 0;
+}
+
+static int // insert U+2598 (quadrant upper left)
+shim_upper_left_quad(struct consolefontdesc* cfd, unsigned idx){
+  unsigned char* glyph = get_glyph(cfd, idx);
+  if(glyph == NULL){
+    return -1;
+  }
+  for(unsigned r = cfd->charheight / 2 ; r < cfd->charheight ; ++r, ++glyph){
+    *glyph = 0;
+  }
+  return 0;
+}
+
+static int // insert U+259D (quadrant upper right)
+shim_upper_right_quad(struct consolefontdesc* cfd, unsigned idx){
+  unsigned char* glyph = get_glyph(cfd, idx);
+  if(glyph == NULL){
+    return -1;
+  }
+  for(unsigned r = 0 ; r < cfd->charheight / 2 ; ++r, ++glyph){
+    *glyph = 0x0f;
+  }
+  for(unsigned r = cfd->charheight / 2 ; r < cfd->charheight ; ++r, ++glyph){
+    *glyph = 0;
+  }
+  return 0;
+}
+
+static int // insert U+2598 (quadrant lower left)
+shim_lower_left_quad(struct consolefontdesc* cfd, unsigned idx){
+  unsigned char* glyph = get_glyph(cfd, idx);
+  if(glyph == NULL){
+    return -1;
+  }
+  for(unsigned r = 0 ; r < cfd->charheight / 2 ; ++r, ++glyph){
+    *glyph = 0;
+  }
+  for(unsigned r = cfd->charheight / 2 ; r < cfd->charheight ; ++r, ++glyph){
+    *glyph = 0xf0;
+  }
+  return 0;
+}
+
+static int // insert U+2597 (quadrant lower right)
+shim_lower_right_quad(struct consolefontdesc* cfd, unsigned idx){
+  unsigned char* glyph = get_glyph(cfd, idx);
+  if(glyph == NULL){
+    return -1;
+  }
+  for(unsigned r = 0 ; r < cfd->charheight / 2 ; ++r, ++glyph){
+    *glyph = 0;
+  }
+  for(unsigned r = cfd->charheight / 2 ; r < cfd->charheight ; ++r, ++glyph){
+    *glyph = 0x0f;
+  }
+  return 0;
+}
+
+static int
+program_line_drawing_chars(const notcurses* nc, struct unimapdesc* map){
+  struct simset {
+    wchar_t* ws;
+  } sets[] = {
+    {
+      .ws = L"/╱",
+    }, {
+      .ws = L"\\╲",
+    }, {
+      .ws = L"X╳",
+    }, {
+      .ws = L"└┕┖┗╘╙╚╰",
+    }, {
+      .ws = L"┘┙┚┛╛╜╝╯",
+    }, {
+      .ws = L"┌┍┎┏╒╓╔╭",
+    }, {
+      .ws = L"┐┑┒┓╕╖╗╮",
+    }, {
+      .ws = L"─━┄┅┈┉╌╍═╼╾",
+    }, {
+      .ws = L"│┃┆┇┊┋╎╏║╽╿",
+    }, {
+      .ws = L"├┝┞┟┠┡┢┣╞╟╠",
+    }, {
+      .ws = L"┤┥┦┧┨┩┪┫╡╢╣",
+    }, {
+      .ws = L"┬┭┮┯┰┱┲┳╤╥╦",
+    }, {
+      .ws = L"┴┵┶┷┸┹┺┻╧╨╩",
+    }, {
+      .ws = L"┼┽┾┿╀╁╂╃╄╅╆╇╈╉╊╋╪╫╬",
+    },
+  };
+  int toadd = 0;
+  for(size_t sidx = 0 ; sidx < sizeof(sets) / sizeof(*sets) ; ++sidx){
+    int fontidx = -1;
+    struct simset* s = &sets[sidx];
+    bool found[wcslen(s->ws)];
+    memset(found, 0, sizeof(found));
+    for(unsigned idx = 0 ; idx < map->entry_ct ; ++idx){
+      for(size_t widx = 0 ; widx < wcslen(s->ws) ; ++widx){
+        if(map->entries[idx].unicode == s->ws[widx]){
+          logtrace(nc, "Found desired character U+%04x -> %03u\n",
+                   map->entries[idx].unicode, map->entries[idx].fontpos);
+          found[widx] = true;
+          if(fontidx == -1){
+            fontidx = map->entries[idx].fontpos;
+          }
+        }
+      }
+    }
+    if(fontidx > -1){
+      for(size_t widx = 0 ; widx < wcslen(s->ws) ; ++widx){
+        if(!found[widx]){
+          logdebug(nc, "Adding mapping U+%04x -> %03u\n", s->ws[widx], fontidx);
+          struct unipair* tmp = realloc(map->entries, sizeof(*map->entries) * (map->entry_ct + 1));
+          if(tmp == NULL){
+            return -1;
+          }
+          map->entries = tmp;
+          map->entries[map->entry_ct].unicode = s->ws[widx];
+          map->entries[map->entry_ct].fontpos = fontidx;
+          ++map->entry_ct;
+          ++toadd;
+        }
+      }
+    }else{
+      logwarning(nc, "Couldn't find any glyphs for set %zu\n", sidx);
+    }
+  }
+  if(toadd == 0){
+    return 0;
+  }
+  if(ioctl(nc->ttyfd, PIO_UNIMAP, map)){
+    logwarning(nc, "Error setting kernel unicode map (%s)\n", strerror(errno));
+    return -1;
+  }
+  loginfo(nc, "Successfully added %d kernel unicode mapping%s\n",
+          toadd, toadd == 1 ? "" : "s");
+  return 0;
+}
+
+static int
+reprogram_linux_font(const notcurses* nc, struct consolefontdesc* cfd,
+                     struct unimapdesc* map){
+  if(ioctl(nc->ttyfd, GIO_FONTX, cfd)){
+    logwarning(nc, "Error reading Linux kernelfont (%s)\n", strerror(errno));
+    return -1;
+  }
+  loginfo(nc, "Kernel font size (glyphcount): %hu\n", cfd->charcount);
+  loginfo(nc, "Kernel font character geometry: 8x%hu\n", cfd->charheight);
+  if(cfd->charcount > 512){
+    logwarning(nc, "Warning: kernel returned excess charcount\n");
+    return -1;
+  }
+  if(ioctl(nc->ttyfd, GIO_UNIMAP, map)){
+    logwarning(nc, "Error reading Linux unimap (%s)\n", strerror(errno));
+    return -1;
+  }
+  loginfo(nc, "Kernel Unimap size: %hu/%hu\n", map->entry_ct, USHRT_MAX);
+  // for certain sets of characters, we're not going to draw them in, but we
+  // do want to ensure they map to something plausible...
+  if(program_line_drawing_chars(nc, map)){
+    return -1;
+  }
+  for(unsigned idx = 0 ; idx < map->entry_ct ; ++idx){
+    // FIXME check to see if our desired codepoints already map
+    //  if already declared, trust it?
+    // if not, see if we ought add one or reuse something
+    // if we want to add, find a good place
+  }
+  return 0;
+}
+
+static int
+reprogram_console_font(const notcurses* nc){
+  struct consolefontdesc cfd = {};
+  cfd.charcount = 512;
+  size_t totsize = 32 * cfd.charcount;
+  cfd.chardata = malloc(totsize);
+  if(cfd.chardata == NULL){
+    logwarning(nc, "Error acquiring %zub for font descriptors (%s)\n", totsize, strerror(errno));
+    return -1;
+  }
+  struct unimapdesc map = {};
+  map.entry_ct = USHRT_MAX;
+  totsize = map.entry_ct * sizeof(struct unipair);
+  map.entries = malloc(totsize);
+  if(map.entries == NULL){
+    logwarning(nc, "Error acquiring %zub for Unicode font map (%s)\n", totsize, strerror(errno));
+    free(cfd.chardata);
+    return -1;
+  }
+  int r = reprogram_linux_font(nc, &cfd, &map);
+  free(cfd.chardata);
+  free(map.entries);
+  return r;
+}
+
 // is the provided fd a Linux console?
-bool is_linux_console(const notcurses* nc){
+bool is_linux_console(const notcurses* nc, unsigned no_font_changes){
+  if(nc->ttyfd < 0){
+    return false;
+  }
   int mode, r;
   if( (r = ioctl(nc->ttyfd, KDGETMODE, &mode)) ){
     logdebug(nc, "Not a Linux console, KDGETMODE failed\n");
     return false;
   }
   loginfo(nc, "Verified Linux console, mode %d\n", mode);
+  if(no_font_changes){
+    logdebug(nc, "Not reprogramming the console font due to option\n");
+    return true;
+  }
+  reprogram_console_font(nc);
   return true;
 }
 #else
-bool is_linux_console(const notcurses* nc){
+bool is_linux_console(const notcurses* nc, unsigned no_font_changes){
   (void)nc;
+  (void)no_font_changes;
   return false;
 }
 #endif

src/lib/notcurses.c

@@ -822,7 +822,7 @@ notcurses* notcurses_init(const notcurses_options* opts, FILE* outfp){
     return NULL;
   }
   ret->ttyfd = get_tty_fd(ret, ret->ttyfp);
-  is_linux_console(ret);
+  is_linux_console(ret, !!(opts->flags & NCOPTION_NO_FONT_CHANGES));
   notcurses_mouse_disable(ret);
   if(ret->ttyfd >= 0){
     if(tcgetattr(ret->ttyfd, &ret->tpreserved)){

src/tetris/background.h

@@ -4,8 +4,7 @@ void DrawBackground(const std::string& s) { // drawn to the standard plane
   backg_->decode();
   ncvisual_options opts{};
   opts.scaling = NCSCALE_STRETCH;
-  auto p = backg_->render(&opts);
-  ncplane_greyscale(p);
+  backg_->render(&opts);
 }
 
 void DrawBoard() { // draw all fixed components of the game