neovim

Neovim text editor
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termkey.c (32130B)


      1 #include <ctype.h>
      2 #include <errno.h>
      3 #include <stdio.h>
      4 #include <string.h>
      5 
      6 #include "nvim/macros_defs.h"
      7 #include "nvim/mbyte.h"
      8 #include "nvim/memory.h"
      9 #include "nvim/tui/termkey/driver-csi.h"
     10 #include "nvim/tui/termkey/driver-ti.h"
     11 #include "nvim/tui/termkey/termkey-internal.h"
     12 #include "nvim/tui/termkey/termkey.h"
     13 #include "nvim/tui/termkey/termkey_defs.h"
     14 
     15 #ifndef _WIN32
     16 // Include these directly instead of <termios.h> which is system-dependent. #31704
     17 # include <poll.h>  // IWYU pragma: keep
     18 # include <strings.h>  // IWYU pragma: keep
     19 # include <unistd.h>  // IWYU pragma: keep
     20 #else
     21 # include <io.h>
     22 #endif
     23 
     24 #include "tui/termkey/termkey.c.generated.h"
     25 
     26 #ifdef _MSC_VER
     27 # define strcaseeq(a, b) (_stricmp(a, b) == 0)
     28 #else
     29 # define strcaseeq(a, b) (strcasecmp(a, b) == 0)
     30 #endif
     31 
     32 struct TermKeyDriver termkey_driver_ti = {
     33  .name = "terminfo",
     34 
     35  .new_driver = new_driver_ti,
     36  .free_driver = free_driver_ti,
     37 
     38  .start_driver = start_driver_ti,
     39  .stop_driver = stop_driver_ti,
     40 
     41  .peekkey = peekkey_ti,
     42 };
     43 
     44 struct TermKeyDriver termkey_driver_csi = {
     45  .name = "CSI",
     46 
     47  .new_driver = new_driver_csi,
     48  .free_driver = free_driver_csi,
     49 
     50  .peekkey = peekkey_csi,
     51 };
     52 
     53 static struct TermKeyDriver *drivers[] = {
     54  &termkey_driver_ti,
     55  &termkey_driver_csi,
     56  NULL,
     57 };
     58 
     59 static struct {
     60  TermKeySym sym;
     61  const char *name;
     62 } keynames[] = {
     63  { TERMKEY_SYM_NONE,      "NONE" },
     64  { TERMKEY_SYM_BACKSPACE, "Backspace" },
     65  { TERMKEY_SYM_TAB,       "Tab" },
     66  { TERMKEY_SYM_ENTER,     "Enter" },
     67  { TERMKEY_SYM_ESCAPE,    "Escape" },
     68  { TERMKEY_SYM_SPACE,     "Space" },
     69  { TERMKEY_SYM_DEL,       "DEL" },
     70  { TERMKEY_SYM_UP,        "Up" },
     71  { TERMKEY_SYM_DOWN,      "Down" },
     72  { TERMKEY_SYM_LEFT,      "Left" },
     73  { TERMKEY_SYM_RIGHT,     "Right" },
     74  { TERMKEY_SYM_BEGIN,     "Begin" },
     75  { TERMKEY_SYM_FIND,      "Find" },
     76  { TERMKEY_SYM_INSERT,    "Insert" },
     77  { TERMKEY_SYM_DELETE,    "Delete" },
     78  { TERMKEY_SYM_SELECT,    "Select" },
     79  { TERMKEY_SYM_PAGEUP,    "PageUp" },
     80  { TERMKEY_SYM_PAGEDOWN,  "PageDown" },
     81  { TERMKEY_SYM_HOME,      "Home" },
     82  { TERMKEY_SYM_END,       "End" },
     83  { TERMKEY_SYM_CANCEL,    "Cancel" },
     84  { TERMKEY_SYM_CLEAR,     "Clear" },
     85  { TERMKEY_SYM_CLOSE,     "Close" },
     86  { TERMKEY_SYM_COMMAND,   "Command" },
     87  { TERMKEY_SYM_COPY,      "Copy" },
     88  { TERMKEY_SYM_EXIT,      "Exit" },
     89  { TERMKEY_SYM_HELP,      "Help" },
     90  { TERMKEY_SYM_MARK,      "Mark" },
     91  { TERMKEY_SYM_MESSAGE,   "Message" },
     92  { TERMKEY_SYM_MOVE,      "Move" },
     93  { TERMKEY_SYM_OPEN,      "Open" },
     94  { TERMKEY_SYM_OPTIONS,   "Options" },
     95  { TERMKEY_SYM_PRINT,     "Print" },
     96  { TERMKEY_SYM_REDO,      "Redo" },
     97  { TERMKEY_SYM_REFERENCE, "Reference" },
     98  { TERMKEY_SYM_REFRESH,   "Refresh" },
     99  { TERMKEY_SYM_REPLACE,   "Replace" },
    100  { TERMKEY_SYM_RESTART,   "Restart" },
    101  { TERMKEY_SYM_RESUME,    "Resume" },
    102  { TERMKEY_SYM_SAVE,      "Save" },
    103  { TERMKEY_SYM_SUSPEND,   "Suspend" },
    104  { TERMKEY_SYM_UNDO,      "Undo" },
    105  { TERMKEY_SYM_KP0,       "KP0" },
    106  { TERMKEY_SYM_KP1,       "KP1" },
    107  { TERMKEY_SYM_KP2,       "KP2" },
    108  { TERMKEY_SYM_KP3,       "KP3" },
    109  { TERMKEY_SYM_KP4,       "KP4" },
    110  { TERMKEY_SYM_KP5,       "KP5" },
    111  { TERMKEY_SYM_KP6,       "KP6" },
    112  { TERMKEY_SYM_KP7,       "KP7" },
    113  { TERMKEY_SYM_KP8,       "KP8" },
    114  { TERMKEY_SYM_KP9,       "KP9" },
    115  { TERMKEY_SYM_KPENTER,   "KPEnter" },
    116  { TERMKEY_SYM_KPPLUS,    "KPPlus" },
    117  { TERMKEY_SYM_KPMINUS,   "KPMinus" },
    118  { TERMKEY_SYM_KPMULT,    "KPMult" },
    119  { TERMKEY_SYM_KPDIV,     "KPDiv" },
    120  { TERMKEY_SYM_KPCOMMA,   "KPComma" },
    121  { TERMKEY_SYM_KPPERIOD,  "KPPeriod" },
    122  { TERMKEY_SYM_KPEQUALS,  "KPEquals" },
    123  { 0, NULL },
    124 };
    125 
    126 // Mouse event names
    127 static const char *evnames[] = { "Unknown", "Press", "Drag", "Release" };
    128 
    129 #define CHARAT(i) (tk->buffer[tk->buffstart + (i)])
    130 
    131 #ifdef DEBUG
    132 // Some internal debugging functions
    133 
    134 static void print_buffer(TermKey *tk)
    135 {
    136  int i;
    137  for (i = 0; i < tk->buffcount && i < 20; i++) {
    138    fprintf(stderr, "%02x ", CHARAT(i));
    139  }
    140  if (tk->buffcount > 20) {
    141    fprintf(stderr, "...");
    142  }
    143 }
    144 
    145 static void print_key(TermKey *tk, TermKeyKey *key)
    146 {
    147  switch (key->type) {
    148  case TERMKEY_TYPE_UNICODE:
    149    fprintf(stderr, "Unicode codepoint=U+%04lx utf8='%s'", key->code.codepoint, key->utf8);
    150    break;
    151  case TERMKEY_TYPE_FUNCTION:
    152    fprintf(stderr, "Function F%d", key->code.number);
    153    break;
    154  case TERMKEY_TYPE_KEYSYM:
    155    fprintf(stderr, "Keysym sym=%d(%s)", key->code.sym, termkey_get_keyname(tk, key->code.sym));
    156    break;
    157  case TERMKEY_TYPE_MOUSE: {
    158    TermKeyMouseEvent ev;
    159    int button, line, col;
    160    termkey_interpret_mouse(tk, key, &ev, &button, &line, &col);
    161    fprintf(stderr, "Mouse ev=%d button=%d pos=(%d,%d)\n", ev, button, line, col);
    162  }
    163  break;
    164  case TERMKEY_TYPE_POSITION: {
    165    int line, col;
    166    termkey_interpret_position(tk, key, &line, &col);
    167    fprintf(stderr, "Position report pos=(%d,%d)\n", line, col);
    168  }
    169  break;
    170  case TERMKEY_TYPE_MODEREPORT: {
    171    int initial, mode, value;
    172    termkey_interpret_modereport(tk, key, &initial, &mode, &value);
    173    fprintf(stderr, "Mode report mode=%s %d val=%d\n", initial == '?' ? "DEC" : "ANSI", mode,
    174            value);
    175  }
    176  break;
    177  case TERMKEY_TYPE_DCS:
    178    fprintf(stderr, "Device Control String");
    179    break;
    180  case TERMKEY_TYPE_OSC:
    181    fprintf(stderr, "Operating System Control");
    182    break;
    183  case TERMKEY_TYPE_APC:
    184    fprintf(stderr, "Application Program Command");
    185    break;
    186  case TERMKEY_TYPE_UNKNOWN_CSI:
    187    fprintf(stderr, "unknown CSI\n");
    188    break;
    189  }
    190 
    191  int m = key->modifiers;
    192  fprintf(stderr, " mod=%s%s%s+%02x",
    193          (m & TERMKEY_KEYMOD_CTRL ? "C" : ""),
    194          (m & TERMKEY_KEYMOD_ALT ? "A" : ""),
    195          (m & TERMKEY_KEYMOD_SHIFT ? "S" : ""),
    196          m & ~(TERMKEY_KEYMOD_CTRL|TERMKEY_KEYMOD_ALT|TERMKEY_KEYMOD_SHIFT));
    197 }
    198 
    199 static const char *res2str(TermKeyResult res)
    200 {
    201  static char errorbuffer[256];
    202 
    203  switch (res) {
    204  case TERMKEY_RES_KEY:
    205    return "TERMKEY_RES_KEY";
    206  case TERMKEY_RES_EOF:
    207    return "TERMKEY_RES_EOF";
    208  case TERMKEY_RES_AGAIN:
    209    return "TERMKEY_RES_AGAIN";
    210  case TERMKEY_RES_NONE:
    211    return "TERMKEY_RES_NONE";
    212  case TERMKEY_RES_ERROR:
    213    snprintf(errorbuffer, sizeof errorbuffer, "TERMKEY_RES_ERROR(errno=%d)\n", errno);
    214    return (const char *)errorbuffer;
    215  }
    216 
    217  return "unknown";
    218 }
    219 #endif
    220 
    221 TermKeyResult termkey_interpret_string(TermKey *tk, const TermKeyKey *key, const char **strp)
    222 {
    223  struct TermKeyDriverNode *p;
    224  for (p = tk->drivers; p; p = p->next) {
    225    if (p->driver == &termkey_driver_csi) {
    226      break;
    227    }
    228  }
    229 
    230  if (!p) {
    231    return TERMKEY_RES_NONE;
    232  }
    233 
    234  if (key->type != TERMKEY_TYPE_DCS
    235      && key->type != TERMKEY_TYPE_OSC
    236      && key->type != TERMKEY_TYPE_APC) {
    237    return TERMKEY_RES_NONE;
    238  }
    239 
    240  TermKeyCsi *csi = p->info;
    241 
    242  if (csi->saved_string_id != key->code.number) {
    243    return TERMKEY_RES_NONE;
    244  }
    245 
    246  *strp = csi->saved_string;
    247 
    248  return TERMKEY_RES_KEY;
    249 }
    250 
    251 /// Similar to snprintf(str, size, "%s", src) except it turns CamelCase into
    252 /// space separated values
    253 static int snprint_cameltospaces(char *str, size_t size, const char *src)
    254 {
    255  int prev_lower = 0;
    256  size_t l = 0;
    257  while (*src && l < size - 1) {
    258    if (isupper(*src) && prev_lower) {
    259      if (str) {
    260        str[l++] = ' ';
    261      }
    262      if (l >= size - 1) {
    263        break;
    264      }
    265    }
    266    prev_lower = islower(*src);
    267    str[l++] = (char)tolower(*src++);
    268  }
    269  str[l] = 0;
    270  // For consistency with snprintf, return the number of bytes that would have
    271  // been written, excluding '\0'
    272  while (*src) {
    273    if (isupper(*src) && prev_lower) {
    274      l++;
    275    }
    276    prev_lower = islower(*src);
    277    src++; l++;
    278  }
    279  return (int)l;
    280 }
    281 
    282 /// Similar to strcmp(str, strcamel, n) except that:
    283 ///    it compares CamelCase in strcamel with space separated values in str;
    284 ///    it takes char**s and updates them
    285 /// n counts bytes of strcamel, not str
    286 static int strpncmp_camel(const char **strp, const char **strcamelp, size_t n)
    287 {
    288  const char *str = *strp, *strcamel = *strcamelp;
    289  int prev_lower = 0;
    290 
    291  for (; (*str || *strcamel) && n; n--) {
    292    char b = (char)tolower(*strcamel);
    293    if (isupper(*strcamel) && prev_lower) {
    294      if (*str != ' ') {
    295        break;
    296      }
    297      str++;
    298      if (*str != b) {
    299        break;
    300      }
    301    } else if (*str != b) {
    302      break;
    303    }
    304 
    305    prev_lower = islower(*strcamel);
    306 
    307    str++;
    308    strcamel++;
    309  }
    310 
    311  *strp = str;
    312  *strcamelp = strcamel;
    313  return *str - *strcamel;
    314 }
    315 
    316 static TermKey *termkey_alloc(void)
    317 {
    318  TermKey *tk = xmalloc(sizeof(TermKey));
    319 
    320  // Default all the object fields but don't allocate anything
    321 
    322  tk->fd = -1;
    323  tk->flags = 0;
    324  tk->canonflags = 0;
    325 
    326  tk->buffer = NULL;
    327  tk->buffstart = 0;
    328  tk->buffcount = 0;
    329  tk->buffsize = 256;  // bytes
    330  tk->hightide = 0;
    331 
    332 #ifdef HAVE_TERMIOS
    333  tk->restore_termios_valid = 0;
    334 #endif
    335 
    336  tk->ti_getstr_hook = NULL;
    337  tk->ti_getstr_hook_data = NULL;
    338 
    339  tk->waittime = 50;  // msec
    340 
    341  tk->is_closed = 0;
    342  tk->is_started = 0;
    343 
    344  tk->nkeynames = 64;
    345  tk->keynames = NULL;
    346 
    347  for (int i = 0; i < 32; i++) {
    348    tk->c0[i].sym = TERMKEY_SYM_NONE;
    349  }
    350 
    351  tk->drivers = NULL;
    352 
    353  tk->method.emit_codepoint = &emit_codepoint;
    354  tk->method.peekkey_simple = &peekkey_simple;
    355  tk->method.peekkey_mouse = &peekkey_mouse;
    356 
    357  return tk;
    358 }
    359 
    360 static int termkey_init(TermKey *tk, TerminfoEntry *term)
    361 {
    362  tk->buffer = xmalloc(tk->buffsize);
    363  tk->keynames = xmalloc(sizeof(tk->keynames[0]) * (size_t)tk->nkeynames);
    364 
    365  int i;
    366  for (i = 0; i < tk->nkeynames; i++) {
    367    tk->keynames[i] = NULL;
    368  }
    369 
    370  for (i = 0; keynames[i].name; i++) {
    371    if (termkey_register_keyname(tk, keynames[i].sym, keynames[i].name) == -1) {
    372      goto abort_free_keynames;
    373    }
    374  }
    375 
    376  register_c0(tk, TERMKEY_SYM_TAB,    0x09, NULL);
    377  register_c0(tk, TERMKEY_SYM_ENTER,  0x0d, NULL);
    378  register_c0(tk, TERMKEY_SYM_ESCAPE, 0x1b, NULL);
    379 
    380  struct TermKeyDriverNode *tail = NULL;
    381 
    382  for (i = 0; drivers[i]; i++) {
    383    void *info = (*drivers[i]->new_driver)(tk, term);
    384    if (!info) {
    385      continue;
    386    }
    387 
    388 #ifdef DEBUG
    389    fprintf(stderr, "Loading the %s driver...\n", drivers[i]->name);
    390 #endif
    391 
    392    struct TermKeyDriverNode *thisdrv = xmalloc(sizeof(*thisdrv));
    393    if (!thisdrv) {
    394      goto abort_free_drivers;
    395    }
    396 
    397    thisdrv->driver = drivers[i];
    398    thisdrv->info = info;
    399    thisdrv->next = NULL;
    400 
    401    if (!tail) {
    402      tk->drivers = thisdrv;
    403    } else {
    404      tail->next = thisdrv;
    405    }
    406 
    407    tail = thisdrv;
    408 
    409 #ifdef DEBUG
    410    fprintf(stderr, "Loaded %s driver\n", drivers[i]->name);
    411 #endif
    412  }
    413 
    414  if (!tk->drivers) {
    415    errno = ENOENT;
    416    goto abort_free_keynames;
    417  }
    418 
    419  return 1;
    420 
    421 abort_free_drivers:
    422  for (struct TermKeyDriverNode *p = tk->drivers; p;) {
    423    (*p->driver->free_driver)(p->info);
    424    struct TermKeyDriverNode *next = p->next;
    425    xfree(p);
    426    p = next;
    427  }
    428 
    429 abort_free_keynames:
    430  xfree(tk->keynames);
    431  xfree(tk->buffer);
    432 
    433  return 0;
    434 }
    435 
    436 TermKey *termkey_new_abstract(TerminfoEntry *term, int flags)
    437 {
    438  TermKey *tk = termkey_alloc();
    439  if (!tk) {
    440    return NULL;
    441  }
    442 
    443  tk->fd = -1;
    444 
    445  termkey_set_flags(tk, flags);
    446 
    447  if (!termkey_init(tk, term)) {
    448    xfree(tk);
    449    return NULL;
    450  }
    451 
    452  if (!(flags & TERMKEY_FLAG_NOSTART) && !termkey_start(tk)) {
    453    goto abort;
    454  }
    455 
    456  return tk;
    457 
    458 abort:
    459  xfree(tk);
    460  return NULL;
    461 }
    462 
    463 void termkey_free(TermKey *tk)
    464 {
    465  xfree(tk->buffer); tk->buffer = NULL;
    466  xfree(tk->keynames); tk->keynames = NULL;
    467 
    468  struct TermKeyDriverNode *p;
    469  for (p = tk->drivers; p;) {
    470    (*p->driver->free_driver)(p->info);
    471    struct TermKeyDriverNode *next = p->next;
    472    xfree(p);
    473    p = next;
    474  }
    475 
    476  xfree(tk);
    477 }
    478 
    479 void termkey_destroy(TermKey *tk)
    480 {
    481  if (tk->is_started) {
    482    termkey_stop(tk);
    483  }
    484 
    485  termkey_free(tk);
    486 }
    487 
    488 void termkey_hook_terminfo_getstr(TermKey *tk, TermKey_Terminfo_Getstr_Hook *hookfn, void *data)
    489 {
    490  tk->ti_getstr_hook = hookfn;
    491  tk->ti_getstr_hook_data = data;
    492 }
    493 
    494 int termkey_start(TermKey *tk)
    495 {
    496  if (tk->is_started) {
    497    return 1;
    498  }
    499 
    500 #ifdef HAVE_TERMIOS
    501  if (tk->fd != -1 && !(tk->flags & TERMKEY_FLAG_NOTERMIOS)) {
    502    struct termios termios;
    503    if (tcgetattr(tk->fd, &termios) == 0) {
    504      tk->restore_termios = termios;
    505      tk->restore_termios_valid = 1;
    506 
    507      termios.c_iflag &= (tcflag_t) ~(IXON|INLCR|ICRNL);
    508      termios.c_lflag &= (tcflag_t) ~(ICANON|ECHO
    509 # ifdef IEXTEN
    510                                      | IEXTEN
    511 # endif
    512                                      );
    513      termios.c_cc[VMIN] = 1;
    514      termios.c_cc[VTIME] = 0;
    515 
    516      if (tk->flags & TERMKEY_FLAG_CTRLC) {
    517        // want no signal keys at all, so just disable ISIG
    518        termios.c_lflag &= (tcflag_t) ~ISIG;
    519      } else {
    520        // Disable Ctrl-\==VQUIT and Ctrl-D==VSUSP but leave Ctrl-C as SIGINT
    521        termios.c_cc[VQUIT] = _POSIX_VDISABLE;
    522        termios.c_cc[VSUSP] = _POSIX_VDISABLE;
    523        // Some OSes have Ctrl-Y==VDSUSP
    524 # ifdef VDSUSP
    525        termios.c_cc[VDSUSP] = _POSIX_VDISABLE;
    526 # endif
    527      }
    528 
    529 # ifdef DEBUG
    530      fprintf(stderr, "Setting termios(3) flags\n");
    531 # endif
    532      tcsetattr(tk->fd, TCSANOW, &termios);
    533    }
    534  }
    535 #endif
    536 
    537  struct TermKeyDriverNode *p;
    538  for (p = tk->drivers; p; p = p->next) {
    539    if (p->driver->start_driver) {
    540      if (!(*p->driver->start_driver)(tk, p->info)) {
    541        return 0;
    542      }
    543    }
    544  }
    545 
    546 #ifdef DEBUG
    547  fprintf(stderr, "Drivers started; termkey instance %p is ready\n", tk);
    548 #endif
    549 
    550  tk->is_started = 1;
    551  return 1;
    552 }
    553 
    554 int termkey_stop(TermKey *tk)
    555 {
    556  if (!tk->is_started) {
    557    return 1;
    558  }
    559 
    560  struct TermKeyDriverNode *p;
    561  for (p = tk->drivers; p; p = p->next) {
    562    if (p->driver->stop_driver) {
    563      (*p->driver->stop_driver)(tk, p->info);
    564    }
    565  }
    566 
    567 #ifdef HAVE_TERMIOS
    568  if (tk->restore_termios_valid) {
    569    tcsetattr(tk->fd, TCSANOW, &tk->restore_termios);
    570  }
    571 #endif
    572 
    573  tk->is_started = 0;
    574 
    575  return 1;
    576 }
    577 
    578 void termkey_set_flags(TermKey *tk, int newflags)
    579 {
    580  tk->flags = newflags;
    581 
    582  if (tk->flags & TERMKEY_FLAG_SPACESYMBOL) {
    583    tk->canonflags |= TERMKEY_CANON_SPACESYMBOL;
    584  } else {
    585    tk->canonflags &= ~TERMKEY_CANON_SPACESYMBOL;
    586  }
    587 }
    588 
    589 int termkey_get_canonflags(TermKey *tk)
    590 {
    591  return tk->canonflags;
    592 }
    593 
    594 void termkey_set_canonflags(TermKey *tk, int flags)
    595 {
    596  tk->canonflags = flags;
    597 
    598  if (tk->canonflags & TERMKEY_CANON_SPACESYMBOL) {
    599    tk->flags |= TERMKEY_FLAG_SPACESYMBOL;
    600  } else {
    601    tk->flags &= ~TERMKEY_FLAG_SPACESYMBOL;
    602  }
    603 }
    604 
    605 size_t termkey_get_buffer_size(TermKey *tk)
    606 {
    607  return tk->buffsize;
    608 }
    609 
    610 int termkey_set_buffer_size(TermKey *tk, size_t size)
    611 {
    612  unsigned char *buffer = xrealloc(tk->buffer, size);
    613 
    614  tk->buffer = buffer;
    615  tk->buffsize = size;
    616 
    617  return 1;
    618 }
    619 
    620 size_t termkey_get_buffer_remaining(TermKey *tk)
    621 {
    622  // Return the total number of free bytes in the buffer, because that's what
    623  // is available to the user.
    624  return tk->buffsize - tk->buffcount;
    625 }
    626 
    627 static void eat_bytes(TermKey *tk, size_t count)
    628 {
    629  if (count >= tk->buffcount) {
    630    tk->buffstart = 0;
    631    tk->buffcount = 0;
    632    return;
    633  }
    634 
    635  tk->buffstart += count;
    636  tk->buffcount -= count;
    637 }
    638 
    639 int fill_utf8(int codepoint, char *str)
    640 {
    641  int nbytes = utf_char2bytes(codepoint, str);
    642  str[nbytes] = 0;
    643  return nbytes;
    644 }
    645 
    646 static TermKeyResult parse_utf8(const unsigned char *bytes, size_t len, int *cp, size_t *nbytep)
    647 {
    648  unsigned nbytes;
    649 
    650  unsigned char b0 = bytes[0];
    651 
    652  if (b0 < 0x80) {
    653    // Single byte ASCII
    654    *cp = b0;
    655    *nbytep = 1;
    656    return TERMKEY_RES_KEY;
    657  } else if (b0 < 0xc0) {
    658    // Starts with a continuation byte - that's not right
    659    *cp = UNICODE_INVALID;
    660    *nbytep = 1;
    661    return TERMKEY_RES_KEY;
    662  } else if (b0 < 0xe0) {
    663    nbytes = 2;
    664    *cp = b0 & 0x1f;
    665  } else if (b0 < 0xf0) {
    666    nbytes = 3;
    667    *cp = b0 & 0x0f;
    668  } else if (b0 < 0xf8) {
    669    nbytes = 4;
    670    *cp = b0 & 0x07;
    671  } else if (b0 < 0xfc) {
    672    nbytes = 5;
    673    *cp = b0 & 0x03;
    674  } else if (b0 < 0xfe) {
    675    nbytes = 6;
    676    *cp = b0 & 0x01;
    677  } else {
    678    *cp = UNICODE_INVALID;
    679    *nbytep = 1;
    680    return TERMKEY_RES_KEY;
    681  }
    682 
    683  for (unsigned b = 1; b < nbytes; b++) {
    684    unsigned char cb;
    685 
    686    if (b >= len) {
    687      return TERMKEY_RES_AGAIN;
    688    }
    689 
    690    cb = bytes[b];
    691    if (cb < 0x80 || cb >= 0xc0) {
    692      *cp = UNICODE_INVALID;
    693      *nbytep = b;
    694      return TERMKEY_RES_KEY;
    695    }
    696 
    697    *cp <<= 6;
    698    *cp |= cb & 0x3f;
    699  }
    700 
    701  // Check for overlong sequences
    702  if ((int)nbytes > utf_char2len(*cp)) {
    703    *cp = UNICODE_INVALID;
    704  }
    705 
    706  // Check for UTF-16 surrogates or invalid *cps
    707  if ((*cp >= 0xD800 && *cp <= 0xDFFF)
    708      || *cp == 0xFFFE
    709      || *cp == 0xFFFF) {
    710    *cp = UNICODE_INVALID;
    711  }
    712 
    713  *nbytep = nbytes;
    714  return TERMKEY_RES_KEY;
    715 }
    716 
    717 static void emit_codepoint(TermKey *tk, int codepoint, TermKeyKey *key)
    718 {
    719  if (codepoint == 0) {
    720    // ASCII NUL = Ctrl-Space
    721    key->type = TERMKEY_TYPE_KEYSYM;
    722    key->code.sym = TERMKEY_SYM_SPACE;
    723    key->modifiers = TERMKEY_KEYMOD_CTRL;
    724  } else if (codepoint < 0x20 && !(tk->flags & TERMKEY_FLAG_KEEPC0)) {
    725    // C0 range
    726    key->code.codepoint = 0;
    727    key->modifiers = 0;
    728 
    729    if (!(tk->flags & TERMKEY_FLAG_NOINTERPRET) && tk->c0[codepoint].sym != TERMKEY_SYM_UNKNOWN) {
    730      key->code.sym = tk->c0[codepoint].sym;
    731      key->modifiers |= tk->c0[codepoint].modifier_set;
    732    }
    733 
    734    if (!key->code.sym) {
    735      key->type = TERMKEY_TYPE_UNICODE;
    736      // Generically modified Unicode ought not report the SHIFT state, or else
    737      // we get into complications trying to report Shift-; vs : and so on...
    738      // In order to be able to represent Ctrl-Shift-A as CTRL modified
    739      // unicode A, we need to call Ctrl-A simply 'a', lowercase
    740      if (codepoint + 0x40 >= 'A' && codepoint + 0x40 <= 'Z') {
    741        // it's a letter - use lowercase instead
    742        key->code.codepoint = codepoint + 0x60;
    743      } else {
    744        key->code.codepoint = codepoint + 0x40;
    745      }
    746      key->modifiers = TERMKEY_KEYMOD_CTRL;
    747    } else {
    748      key->type = TERMKEY_TYPE_KEYSYM;
    749    }
    750  } else if (codepoint == 0x7f && !(tk->flags & TERMKEY_FLAG_NOINTERPRET)) {
    751    // ASCII DEL
    752    key->type = TERMKEY_TYPE_KEYSYM;
    753    key->code.sym = TERMKEY_SYM_DEL;
    754    key->modifiers = 0;
    755  } else if (codepoint > 0 && codepoint < 0x80) {
    756    // ASCII lowbyte range
    757    key->type = TERMKEY_TYPE_UNICODE;
    758    key->code.codepoint = codepoint;
    759    key->modifiers = 0;
    760  } else if (codepoint >= 0x80 && codepoint < 0xa0) {
    761    // UTF-8 never starts with a C1 byte. So we can be sure of these
    762    key->type = TERMKEY_TYPE_UNICODE;
    763    key->code.codepoint = codepoint - 0x40;
    764    key->modifiers = TERMKEY_KEYMOD_CTRL|TERMKEY_KEYMOD_ALT;
    765  } else {
    766    // UTF-8 codepoint
    767    key->type = TERMKEY_TYPE_UNICODE;
    768    key->code.codepoint = codepoint;
    769    key->modifiers = 0;
    770  }
    771 
    772  termkey_canonicalise(tk, key);
    773 
    774  if (key->type == TERMKEY_TYPE_UNICODE) {
    775    fill_utf8(key->code.codepoint, key->utf8);
    776  }
    777 }
    778 
    779 void termkey_canonicalise(TermKey *tk, TermKeyKey *key)
    780 {
    781  int flags = tk->canonflags;
    782 
    783  if (flags & TERMKEY_CANON_SPACESYMBOL) {
    784    if (key->type == TERMKEY_TYPE_UNICODE && key->code.codepoint == 0x20) {
    785      key->type = TERMKEY_TYPE_KEYSYM;
    786      key->code.sym = TERMKEY_SYM_SPACE;
    787    }
    788  } else {
    789    if (key->type == TERMKEY_TYPE_KEYSYM && key->code.sym == TERMKEY_SYM_SPACE) {
    790      key->type = TERMKEY_TYPE_UNICODE;
    791      key->code.codepoint = 0x20;
    792      fill_utf8(key->code.codepoint, key->utf8);
    793    }
    794  }
    795 
    796  if (flags & TERMKEY_CANON_DELBS) {
    797    if (key->type == TERMKEY_TYPE_KEYSYM && key->code.sym == TERMKEY_SYM_DEL) {
    798      key->code.sym = TERMKEY_SYM_BACKSPACE;
    799    }
    800  }
    801 }
    802 
    803 static TermKeyResult peekkey(TermKey *tk, TermKeyKey *key, int force, size_t *nbytep)
    804 {
    805  int again = 0;
    806 
    807  if (!tk->is_started) {
    808    errno = EINVAL;
    809    return TERMKEY_RES_ERROR;
    810  }
    811 
    812  // Press is the default event type.
    813  key->event = TERMKEY_EVENT_PRESS;
    814 
    815 #ifdef DEBUG
    816  fprintf(stderr, "getkey(force=%d): buffer ", force);
    817  print_buffer(tk);
    818  fprintf(stderr, "\n");
    819 #endif
    820 
    821  if (tk->hightide) {
    822    tk->buffstart += tk->hightide;
    823    tk->buffcount -= tk->hightide;
    824    tk->hightide = 0;
    825  }
    826 
    827  TermKeyResult ret;
    828  struct TermKeyDriverNode *p;
    829  for (p = tk->drivers; p; p = p->next) {
    830    ret = (p->driver->peekkey)(tk, p->info, key, force, nbytep);
    831 
    832 #ifdef DEBUG
    833    fprintf(stderr, "Driver %s yields %s\n", p->driver->name, res2str(ret));
    834 #endif
    835 
    836    switch (ret) {
    837    case TERMKEY_RES_KEY:
    838 #ifdef DEBUG
    839      print_key(tk, key); fprintf(stderr, "\n");
    840 #endif
    841      // Slide the data down to stop it running away
    842      {
    843        size_t halfsize = tk->buffsize / 2;
    844 
    845        if (tk->buffstart > halfsize) {
    846          memcpy(tk->buffer, tk->buffer + halfsize, halfsize);
    847          tk->buffstart -= halfsize;
    848        }
    849      }
    850      FALLTHROUGH;
    851    case TERMKEY_RES_EOF:
    852    case TERMKEY_RES_ERROR:
    853      return ret;
    854 
    855    case TERMKEY_RES_AGAIN:
    856      if (!force) {
    857        again = 1;
    858      }
    859      FALLTHROUGH;
    860    case TERMKEY_RES_NONE:
    861      break;
    862    }
    863  }
    864 
    865  if (again) {
    866    return TERMKEY_RES_AGAIN;
    867  }
    868 
    869  ret = peekkey_simple(tk, key, force, nbytep);
    870 
    871 #ifdef DEBUG
    872  fprintf(stderr, "getkey_simple(force=%d) yields %s\n", force, res2str(ret));
    873  if (ret == TERMKEY_RES_KEY) {
    874    print_key(tk, key); fprintf(stderr, "\n");
    875  }
    876 #endif
    877 
    878  return ret;
    879 }
    880 
    881 static TermKeyResult peekkey_simple(TermKey *tk, TermKeyKey *key, int force, size_t *nbytep)
    882 {
    883  if (tk->buffcount == 0) {
    884    return tk->is_closed ? TERMKEY_RES_EOF : TERMKEY_RES_NONE;
    885  }
    886 
    887  unsigned char b0 = CHARAT(0);
    888 
    889  if (b0 == 0x1b) {
    890    // Escape-prefixed value? Might therefore be Alt+key
    891    if (tk->buffcount == 1) {
    892      // This might be an <Esc> press, or it may want to be part of a longer
    893      // sequence
    894      if (!force) {
    895        return TERMKEY_RES_AGAIN;
    896      }
    897 
    898      (*tk->method.emit_codepoint)(tk, b0, key);
    899      *nbytep = 1;
    900      return TERMKEY_RES_KEY;
    901    }
    902 
    903    // Try another key there
    904    tk->buffstart++;
    905    tk->buffcount--;
    906 
    907    // Run the full driver
    908    TermKeyResult metakey_result = peekkey(tk, key, force, nbytep);
    909 
    910    tk->buffstart--;
    911    tk->buffcount++;
    912 
    913    switch (metakey_result) {
    914    case TERMKEY_RES_KEY:
    915      key->modifiers |= TERMKEY_KEYMOD_ALT;
    916      (*nbytep)++;
    917      break;
    918 
    919    case TERMKEY_RES_NONE:
    920    case TERMKEY_RES_EOF:
    921    case TERMKEY_RES_AGAIN:
    922    case TERMKEY_RES_ERROR:
    923      break;
    924    }
    925 
    926    return metakey_result;
    927  } else if (b0 < 0xa0) {
    928    // Single byte C0, G0 or C1 - C1 is never UTF-8 initial byte
    929    (*tk->method.emit_codepoint)(tk, b0, key);
    930    *nbytep = 1;
    931    return TERMKEY_RES_KEY;
    932  } else if (tk->flags & TERMKEY_FLAG_UTF8) {
    933    // Some UTF-8
    934    int codepoint;
    935    TermKeyResult res = parse_utf8(tk->buffer + tk->buffstart, tk->buffcount, &codepoint, nbytep);
    936 
    937    if (res == TERMKEY_RES_AGAIN && force) {
    938      // There weren't enough bytes for a complete UTF-8 sequence but caller
    939      // demands an answer. About the best thing we can do here is eat as many
    940      // bytes as we have, and emit a UNICODE_INVALID. If the remaining bytes
    941      // arrive later, they'll be invalid too.
    942      codepoint = UNICODE_INVALID;
    943      *nbytep = tk->buffcount;
    944      res = TERMKEY_RES_KEY;
    945    }
    946 
    947    key->type = TERMKEY_TYPE_UNICODE;
    948    key->modifiers = 0;
    949    (*tk->method.emit_codepoint)(tk, codepoint, key);
    950    return res;
    951  } else {
    952    // Non UTF-8 case - just report the raw byte
    953    key->type = TERMKEY_TYPE_UNICODE;
    954    key->code.codepoint = b0;
    955    key->modifiers = 0;
    956 
    957    key->utf8[0] = (char)key->code.codepoint;
    958    key->utf8[1] = 0;
    959 
    960    *nbytep = 1;
    961 
    962    return TERMKEY_RES_KEY;
    963  }
    964 }
    965 
    966 static TermKeyResult peekkey_mouse(TermKey *tk, TermKeyKey *key, size_t *nbytep)
    967 {
    968  if (tk->buffcount < 3) {
    969    return TERMKEY_RES_AGAIN;
    970  }
    971 
    972  key->type = TERMKEY_TYPE_MOUSE;
    973  key->code.mouse[0] = (char)CHARAT(0) - 0x20;
    974  key->code.mouse[1] = (char)CHARAT(1) - 0x20;
    975  key->code.mouse[2] = (char)CHARAT(2) - 0x20;
    976  key->code.mouse[3] = 0;
    977 
    978  key->modifiers = (key->code.mouse[0] & 0x1c) >> 2;
    979  key->code.mouse[0] &= ~0x1c;
    980 
    981  *nbytep = 3;
    982  return TERMKEY_RES_KEY;
    983 }
    984 
    985 TermKeyResult termkey_getkey(TermKey *tk, TermKeyKey *key)
    986 {
    987  size_t nbytes = 0;
    988  TermKeyResult ret = peekkey(tk, key, 0, &nbytes);
    989 
    990  if (ret == TERMKEY_RES_KEY) {
    991    eat_bytes(tk, nbytes);
    992  }
    993 
    994  if (ret == TERMKEY_RES_AGAIN) {
    995    // Call peekkey() again in force mode to obtain whatever it can
    996    (void)peekkey(tk, key, 1, &nbytes);
    997  }
    998  // Don't eat it yet though
    999 
   1000  return ret;
   1001 }
   1002 
   1003 TermKeyResult termkey_getkey_force(TermKey *tk, TermKeyKey *key)
   1004 {
   1005  size_t nbytes = 0;
   1006  TermKeyResult ret = peekkey(tk, key, 1, &nbytes);
   1007 
   1008  if (ret == TERMKEY_RES_KEY) {
   1009    eat_bytes(tk, nbytes);
   1010  }
   1011 
   1012  return ret;
   1013 }
   1014 
   1015 size_t termkey_push_bytes(TermKey *tk, const char *bytes, size_t len)
   1016 {
   1017  if (tk->buffstart) {
   1018    memmove(tk->buffer, tk->buffer + tk->buffstart, tk->buffcount);
   1019    tk->buffstart = 0;
   1020  }
   1021 
   1022  // Not expecting it ever to be greater but doesn't hurt to handle that
   1023  if (tk->buffcount >= tk->buffsize) {
   1024    errno = ENOMEM;
   1025    return (size_t)-1;
   1026  }
   1027 
   1028  if (len > tk->buffsize - tk->buffcount) {
   1029    len = tk->buffsize - tk->buffcount;
   1030  }
   1031 
   1032  // memcpy(), not strncpy() in case of null bytes in input
   1033  memcpy(tk->buffer + tk->buffcount, bytes, len);
   1034  tk->buffcount += len;
   1035 
   1036  return len;
   1037 }
   1038 
   1039 TermKeySym termkey_register_keyname(TermKey *tk, TermKeySym sym, const char *name)
   1040 {
   1041  if (!sym) {
   1042    sym = tk->nkeynames;
   1043  }
   1044 
   1045  if (sym >= tk->nkeynames) {
   1046    const char **new_keynames = xrealloc(tk->keynames, sizeof(new_keynames[0]) * ((size_t)sym + 1));
   1047 
   1048    tk->keynames = new_keynames;
   1049 
   1050    // Fill in the hole
   1051    for (int i = tk->nkeynames; i < sym; i++) {
   1052      tk->keynames[i] = NULL;
   1053    }
   1054 
   1055    tk->nkeynames = sym + 1;
   1056  }
   1057 
   1058  tk->keynames[sym] = name;
   1059 
   1060  return sym;
   1061 }
   1062 
   1063 const char *termkey_get_keyname(TermKey *tk, TermKeySym sym)
   1064 {
   1065  if (sym == TERMKEY_SYM_UNKNOWN) {
   1066    return "UNKNOWN";
   1067  }
   1068 
   1069  if (sym < tk->nkeynames) {
   1070    return tk->keynames[sym];
   1071  }
   1072 
   1073  return "UNKNOWN";
   1074 }
   1075 
   1076 static const char *termkey_lookup_keyname_format(TermKey *tk, const char *str, TermKeySym *sym,
   1077                                                 TermKeyFormat format)
   1078 {
   1079  // We store an array, so we can't do better than a linear search. Doesn't
   1080  // matter because user won't be calling this too often
   1081 
   1082  for (*sym = 0; *sym < tk->nkeynames; (*sym)++) {
   1083    const char *thiskey = tk->keynames[*sym];
   1084    if (!thiskey) {
   1085      continue;
   1086    }
   1087    size_t len = strlen(thiskey);
   1088    if (format & TERMKEY_FORMAT_LOWERSPACE) {
   1089      const char *thisstr = str;
   1090      if (strpncmp_camel(&thisstr, &thiskey, len) == 0) {
   1091        return thisstr;
   1092      }
   1093    } else {
   1094      if (strncmp(str, thiskey, len) == 0) {
   1095        return (char *)str + len;
   1096      }
   1097    }
   1098  }
   1099 
   1100  return NULL;
   1101 }
   1102 
   1103 const char *termkey_lookup_keyname(TermKey *tk, const char *str, TermKeySym *sym)
   1104 {
   1105  return termkey_lookup_keyname_format(tk, str, sym, 0);
   1106 }
   1107 
   1108 static TermKeySym register_c0(TermKey *tk, TermKeySym sym, unsigned char ctrl, const char *name)
   1109 {
   1110  return register_c0_full(tk, sym, 0, 0, ctrl, name);
   1111 }
   1112 
   1113 static TermKeySym register_c0_full(TermKey *tk, TermKeySym sym, int modifier_set, int modifier_mask,
   1114                                   unsigned char ctrl, const char *name)
   1115 {
   1116  if (ctrl >= 0x20) {
   1117    errno = EINVAL;
   1118    return -1;
   1119  }
   1120 
   1121  if (name) {
   1122    sym = termkey_register_keyname(tk, sym, name);
   1123  }
   1124 
   1125  tk->c0[ctrl].sym = sym;
   1126  tk->c0[ctrl].modifier_set = modifier_set;
   1127  tk->c0[ctrl].modifier_mask = modifier_mask;
   1128 
   1129  return sym;
   1130 }
   1131 
   1132 static struct modnames {
   1133  const char *shift, *alt, *ctrl;
   1134 }
   1135 modnames[] = {
   1136  { "S",     "A",    "C" },    // 0
   1137  { "Shift", "Alt",  "Ctrl" },  // LONGMOD
   1138  { "S",     "M",    "C" },    // ALTISMETA
   1139  { "Shift", "Meta", "Ctrl" },  // ALTISMETA+LONGMOD
   1140  { "s",     "a",    "c" },    // LOWERMOD
   1141  { "shift", "alt",  "ctrl" },  // LOWERMOD+LONGMOD
   1142  { "s",     "m",    "c" },    // LOWERMOD+ALTISMETA
   1143  { "shift", "meta", "ctrl" },  // LOWERMOD+ALTISMETA+LONGMOD
   1144 };
   1145 
   1146 size_t termkey_strfkey(TermKey *tk, char *buffer, size_t len, TermKeyKey *key, TermKeyFormat format)
   1147 {
   1148  size_t pos = 0;
   1149  size_t l = 0;
   1150 
   1151  struct modnames *mods = &modnames[!!(format & TERMKEY_FORMAT_LONGMOD) +
   1152                                    !!(format & TERMKEY_FORMAT_ALTISMETA) * 2 +
   1153                                    !!(format & TERMKEY_FORMAT_LOWERMOD) * 4];
   1154 
   1155  int wrapbracket = (format & TERMKEY_FORMAT_WRAPBRACKET)
   1156                    && (key->type != TERMKEY_TYPE_UNICODE || key->modifiers != 0);
   1157 
   1158  char sep = (format & TERMKEY_FORMAT_SPACEMOD) ? ' ' : '-';
   1159 
   1160  if (format & TERMKEY_FORMAT_CARETCTRL
   1161      && key->type == TERMKEY_TYPE_UNICODE
   1162      && key->modifiers == TERMKEY_KEYMOD_CTRL) {
   1163    long codepoint = key->code.codepoint;
   1164 
   1165    // Handle some of the special cases first
   1166    if (codepoint >= 'a' && codepoint <= 'z') {
   1167      l = (size_t)snprintf(buffer + pos, len - pos, wrapbracket ? "<^%c>" : "^%c",
   1168                           (char)codepoint - 0x20);
   1169      if (l <= 0) {
   1170        return pos;
   1171      }
   1172      pos += l;
   1173      return pos;
   1174    } else if ((codepoint >= '@' && codepoint < 'A')
   1175               || (codepoint > 'Z' && codepoint <= '_')) {
   1176      l = (size_t)snprintf(buffer + pos, len - pos, wrapbracket ? "<^%c>" : "^%c", (char)codepoint);
   1177      if (l <= 0) {
   1178        return pos;
   1179      }
   1180      pos += l;
   1181      return pos;
   1182    }
   1183  }
   1184 
   1185  if (wrapbracket) {
   1186    l = (size_t)snprintf(buffer + pos, len - pos, "<");
   1187    if (l <= 0) {
   1188      return pos;
   1189    }
   1190    pos += l;
   1191  }
   1192 
   1193  if (key->modifiers & TERMKEY_KEYMOD_ALT) {
   1194    l = (size_t)snprintf(buffer + pos, len - pos, "%s%c", mods->alt, sep);
   1195    if (l <= 0) {
   1196      return pos;
   1197    }
   1198    pos += l;
   1199  }
   1200 
   1201  if (key->modifiers & TERMKEY_KEYMOD_CTRL) {
   1202    l = (size_t)snprintf(buffer + pos, len - pos, "%s%c", mods->ctrl, sep);
   1203    if (l <= 0) {
   1204      return pos;
   1205    }
   1206    pos += l;
   1207  }
   1208 
   1209  if (key->modifiers & TERMKEY_KEYMOD_SHIFT) {
   1210    l = (size_t)snprintf(buffer + pos, len - pos, "%s%c", mods->shift, sep);
   1211    if (l <= 0) {
   1212      return pos;
   1213    }
   1214    pos += l;
   1215  }
   1216 
   1217  switch (key->type) {
   1218  case TERMKEY_TYPE_UNICODE:
   1219    if (!key->utf8[0]) {  // In case of user-supplied key structures
   1220      fill_utf8(key->code.codepoint, key->utf8);
   1221    }
   1222    l = (size_t)snprintf(buffer + pos, len - pos, "%s", key->utf8);
   1223    break;
   1224  case TERMKEY_TYPE_KEYSYM: {
   1225    const char *name = termkey_get_keyname(tk, key->code.sym);
   1226    if (format & TERMKEY_FORMAT_LOWERSPACE) {
   1227      l = (size_t)snprint_cameltospaces(buffer + pos, len - pos, name);
   1228    } else {
   1229      l = (size_t)snprintf(buffer + pos, len - pos, "%s", name);
   1230    }
   1231  }
   1232  break;
   1233  case TERMKEY_TYPE_FUNCTION:
   1234    l = (size_t)snprintf(buffer + pos, len - pos, "%c%d",
   1235                         (format & TERMKEY_FORMAT_LOWERSPACE ? 'f' : 'F'), key->code.number);
   1236    break;
   1237  case TERMKEY_TYPE_MOUSE: {
   1238    TermKeyMouseEvent ev;
   1239    int button;
   1240    int line, col;
   1241    termkey_interpret_mouse(tk, key, &ev, &button, &line, &col);
   1242 
   1243    l = (size_t)snprintf(buffer + pos, len - pos, "Mouse%s(%d)",
   1244                         evnames[ev], button);
   1245 
   1246    if (format & TERMKEY_FORMAT_MOUSE_POS) {
   1247      if (l <= 0) {
   1248        return pos;
   1249      }
   1250      pos += l;
   1251 
   1252      l = (size_t)snprintf(buffer + pos, len - pos, " @ (%u,%u)", col, line);
   1253    }
   1254  }
   1255  break;
   1256  case TERMKEY_TYPE_POSITION:
   1257    l = (size_t)snprintf(buffer + pos, len - pos, "Position");
   1258    break;
   1259  case TERMKEY_TYPE_MODEREPORT: {
   1260    int initial, mode, value;
   1261    termkey_interpret_modereport(tk, key, &initial, &mode, &value);
   1262    if (initial) {
   1263      l = (size_t)snprintf(buffer + pos, len - pos, "Mode(%c%d=%d)", initial, mode, value);
   1264    } else {
   1265      l = (size_t)snprintf(buffer + pos, len - pos, "Mode(%d=%d)", mode, value);
   1266    }
   1267  }
   1268  break;
   1269  case TERMKEY_TYPE_DCS:
   1270    l = (size_t)snprintf(buffer + pos, len - pos, "DCS");
   1271    break;
   1272  case TERMKEY_TYPE_OSC:
   1273    l = (size_t)snprintf(buffer + pos, len - pos, "OSC");
   1274    break;
   1275  case TERMKEY_TYPE_APC:
   1276    l = (size_t)snprintf(buffer + pos, len - pos, "APC");
   1277    break;
   1278  case TERMKEY_TYPE_UNKNOWN_CSI:
   1279    l = (size_t)snprintf(buffer + pos, len - pos, "CSI %c", key->code.number & 0xff);
   1280    break;
   1281  }
   1282 
   1283  if (l <= 0) {
   1284    return pos;
   1285  }
   1286  pos += l;
   1287 
   1288  if (wrapbracket) {
   1289    l = (size_t)snprintf(buffer + pos, len - pos, ">");
   1290    if (l <= 0) {
   1291      return pos;
   1292    }
   1293    pos += l;
   1294  }
   1295 
   1296  return pos;
   1297 }