contrib/nvi2/cl/cl_read.c

   1 /*-
   2  * Copyright (c) 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 1993, 1994, 1995, 1996
   5  *      Keith Bostic.  All rights reserved.
   6  *
   7  * See the LICENSE file for redistribution information.
   8  */
   9
  10 #include "config.h"
  11
  12 #include <sys/types.h>
  13 #include <sys/queue.h>
  14 #include <sys/select.h>
  15
  16 #include <bitstring.h>
  17 #include <errno.h>
  18 #include <fcntl.h>
  19 #include <signal.h>
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <sys/ioctl.h>
  24 #include <termios.h>
  25 #include <unistd.h>
  26
  27 #include "../common/common.h"
  28 #include "../ex/script.h"
  29 #include "cl.h"
  30
  31 /* Pollution by Solaris curses. */
  32 #undef columns
  33 #undef lines
  34
  35 static input_t  cl_read(SCR *,
  36     u_int32_t, char *, size_t, int *, struct timeval *);
  37 static int      cl_resize(SCR *, size_t, size_t);
  38
  39 /*
  40  * cl_event --
  41  *      Return a single event.
  42  *
  43  * PUBLIC: int cl_event(SCR *, EVENT *, u_int32_t, int);
  44  */
  45 int
  46 cl_event(SCR *sp, EVENT *evp, u_int32_t flags, int ms)
  47 {
  48         struct timeval t, *tp;
  49         CL_PRIVATE *clp;
  50         size_t lines, columns;
  51         int changed, nr = 0;
  52         CHAR_T *wp;
  53         size_t wlen;
  54         int rc;
  55
  56         /*
  57          * Queue signal based events.  We never clear SIGHUP or SIGTERM events,
  58          * so that we just keep returning them until the editor dies.
  59          */
  60         clp = CLP(sp);
  61 retest: if (LF_ISSET(EC_INTERRUPT) || F_ISSET(clp, CL_SIGINT)) {
  62                 if (F_ISSET(clp, CL_SIGINT)) {
  63                         F_CLR(clp, CL_SIGINT);
  64                         evp->e_event = E_INTERRUPT;
  65                 } else
  66                         evp->e_event = E_TIMEOUT;
  67                 return (0);
  68         }
  69         if (F_ISSET(clp, CL_SIGHUP | CL_SIGTERM | CL_SIGWINCH)) {
  70                 if (F_ISSET(clp, CL_SIGHUP)) {
  71                         evp->e_event = E_SIGHUP;
  72                         return (0);
  73                 }
  74                 if (F_ISSET(clp, CL_SIGTERM)) {
  75                         evp->e_event = E_SIGTERM;
  76                         return (0);
  77                 }
  78                 if (F_ISSET(clp, CL_SIGWINCH)) {
  79                         F_CLR(clp, CL_SIGWINCH);
  80                         if (cl_ssize(sp, 1, &lines, &columns, &changed))
  81                                 return (1);
  82                         if (changed) {
  83                                 (void)cl_resize(sp, lines, columns);
  84                                 evp->e_event = E_WRESIZE;
  85                                 return (0);
  86                         }
  87                         /* No real change, ignore the signal. */
  88                 }
  89         }
  90
  91         /* Set timer. */
  92         if (ms == 0)
  93                 tp = NULL;
  94         else {
  95                 t.tv_sec = ms / 1000;
  96                 t.tv_usec = (ms % 1000) * 1000;
  97                 tp = &t;
  98         }
  99
 100         /* Read input characters. */
 101 read:
 102         switch (cl_read(sp, LF_ISSET(EC_QUOTED | EC_RAW),
 103             clp->ibuf + clp->skip, SIZE(clp->ibuf) - clp->skip, &nr, tp)) {
 104         case INP_OK:
 105                 rc = INPUT2INT5(sp, clp->cw, clp->ibuf, nr + clp->skip,
 106                                 wp, wlen);
 107                 evp->e_csp = wp;
 108                 evp->e_len = wlen;
 109                 evp->e_event = E_STRING;
 110                 if (rc < 0) {
 111                     int n = -rc;
 112                     memmove(clp->ibuf, clp->ibuf + nr + clp->skip - n, n);
 113                     clp->skip = n;
 114                     if (wlen == 0)
 115                         goto read;
 116                 } else if (rc == 0)
 117                     clp->skip = 0;
 118                 else
 119                     msgq(sp, M_ERR, "323|Invalid input. Truncated.");
 120                 break;
 121         case INP_EOF:
 122                 evp->e_event = E_EOF;
 123                 break;
 124         case INP_ERR:
 125                 evp->e_event = E_ERR;
 126                 break;
 127         case INP_INTR:
 128                 goto retest;
 129         case INP_TIMEOUT:
 130                 evp->e_event = E_TIMEOUT;
 131                 break;
 132         default:
 133                 abort();
 134         }
 135         return (0);
 136 }
 137
 138 /*
 139  * cl_read --
 140  *      Read characters from the input.
 141  */
 142 static input_t
 143 cl_read(SCR *sp, u_int32_t flags, char *bp, size_t blen, int *nrp,
 144     struct timeval *tp)
 145 {
 146         struct termios term1, term2;
 147         CL_PRIVATE *clp;
 148         GS *gp;
 149         fd_set rdfd;
 150         input_t rval;
 151         int maxfd, nr, term_reset;
 152
 153         gp = sp->gp;
 154         clp = CLP(sp);
 155         term_reset = 0;
 156
 157         /*
 158          * 1: A read from a file or a pipe.  In this case, the reads
 159          *    never timeout regardless.  This means that we can hang
 160          *    when trying to complete a map, but we're going to hang
 161          *    on the next read anyway.
 162          */
 163         if (!F_ISSET(clp, CL_STDIN_TTY)) {
 164                 switch (nr = read(STDIN_FILENO, bp, blen)) {
 165                 case 0:
 166                         return (INP_EOF);
 167                 case -1:
 168                         goto err;
 169                 default:
 170                         *nrp = nr;
 171                         return (INP_OK);
 172                 }
 173                 /* NOTREACHED */
 174         }
 175
 176         /*
 177          * 2: A read with an associated timeout, e.g., trying to complete
 178          *    a map sequence.  If input exists, we fall into #3.
 179          */
 180         if (tp != NULL) {
 181                 FD_ZERO(&rdfd);
 182                 FD_SET(STDIN_FILENO, &rdfd);
 183                 switch (select(STDIN_FILENO + 1, &rdfd, NULL, NULL, tp)) {
 184                 case 0:
 185                         return (INP_TIMEOUT);
 186                 case -1:
 187                         goto err;
 188                 default:
 189                         break;
 190                 }
 191         }
 192
 193         /*
 194          * The user can enter a key in the editor to quote a character.  If we
 195          * get here and the next key is supposed to be quoted, do what we can.
 196          * Reset the tty so that the user can enter a ^C, ^Q, ^S.  There's an
 197          * obvious race here, when the key has already been entered, but there's
 198          * nothing that we can do to fix that problem.
 199          *
 200          * The editor can ask for the next literal character even thought it's
 201          * generally running in line-at-a-time mode.  Do what we can.
 202          */
 203         if (LF_ISSET(EC_QUOTED | EC_RAW) && !tcgetattr(STDIN_FILENO, &term1)) {
 204                 term_reset = 1;
 205                 if (LF_ISSET(EC_QUOTED)) {
 206                         term2 = term1;
 207                         term2.c_lflag &= ~ISIG;
 208                         term2.c_iflag &= ~(IXON | IXOFF);
 209                         (void)tcsetattr(STDIN_FILENO,
 210                             TCSASOFT | TCSADRAIN, &term2);
 211                 } else
 212                         (void)tcsetattr(STDIN_FILENO,
 213                             TCSASOFT | TCSADRAIN, &clp->vi_enter);
 214         }
 215
 216         /*
 217          * 3: Wait for input.
 218          *
 219          * Select on the command input and scripting window file descriptors.
 220          * It's ugly that we wait on scripting file descriptors here, but it's
 221          * the only way to keep from locking out scripting windows.
 222          */
 223         if (F_ISSET(gp, G_SCRWIN)) {
 224 loop:           FD_ZERO(&rdfd);
 225                 FD_SET(STDIN_FILENO, &rdfd);
 226                 maxfd = STDIN_FILENO;
 227                 if (F_ISSET(sp, SC_SCRIPT)) {
 228                         FD_SET(sp->script->sh_master, &rdfd);
 229                         if (sp->script->sh_master > maxfd)
 230                                 maxfd = sp->script->sh_master;
 231                 }
 232                 switch (select(maxfd + 1, &rdfd, NULL, NULL, NULL)) {
 233                 case 0:
 234                         abort();
 235                 case -1:
 236                         goto err;
 237                 default:
 238                         break;
 239                 }
 240                 if (!FD_ISSET(STDIN_FILENO, &rdfd)) {
 241                         if (sscr_input(sp))
 242                                 return (INP_ERR);
 243                         goto loop;
 244                 }
 245         }
 246
 247         /*
 248          * 4: Read the input.
 249          *
 250          * !!!
 251          * What's going on here is some scary stuff.  Ex runs the terminal in
 252          * canonical mode.  So, the <newline> character terminating a line of
 253          * input is returned in the buffer, but a trailing <EOF> character is
 254          * not similarly included.  As ex uses 0<EOF> and ^<EOF> as autoindent
 255          * commands, it has to see the trailing <EOF> characters to determine
 256          * the difference between the user entering "0ab" and "0<EOF>ab".  We
 257          * leave an extra slot in the buffer, so that we can add a trailing
 258          * <EOF> character if the buffer isn't terminated by a <newline>.  We
 259          * lose if the buffer is too small for the line and exactly N characters
 260          * are entered followed by an <EOF> character.
 261          */
 262 #define ONE_FOR_EOF     1
 263         switch (nr = read(STDIN_FILENO, bp, blen - ONE_FOR_EOF)) {
 264         case  0:                                /* EOF. */
 265                 /*
 266                  * ^D in canonical mode returns a read of 0, i.e. EOF.  EOF is
 267                  * a valid command, but we don't want to loop forever because
 268                  * the terminal driver is returning EOF because the user has
 269                  * disconnected. The editor will almost certainly try to write
 270                  * something before this fires, which should kill us, but You
 271                  * Never Know.
 272                  */
 273                 if (++clp->eof_count < 50) {
 274                         bp[0] = clp->orig.c_cc[VEOF];
 275                         *nrp = 1;
 276                         rval = INP_OK;
 277
 278                 } else
 279                         rval = INP_EOF;
 280                 break;
 281         case -1:                                /* Error or interrupt. */
 282 err:            if (errno == EINTR)
 283                         rval = INP_INTR;
 284                 else {
 285                         rval = INP_ERR;
 286                         msgq(sp, M_SYSERR, "input");
 287                 }
 288                 break;
 289         default:                                /* Input characters. */
 290                 if (F_ISSET(sp, SC_EX) && bp[nr - 1] != '\n')
 291                         bp[nr++] = clp->orig.c_cc[VEOF];
 292                 *nrp = nr;
 293                 clp->eof_count = 0;
 294                 rval = INP_OK;
 295                 break;
 296         }
 297
 298         /* Restore the terminal state if it was modified. */
 299         if (term_reset)
 300                 (void)tcsetattr(STDIN_FILENO, TCSASOFT | TCSADRAIN, &term1);
 301         return (rval);
 302 }
 303
 304 /*
 305  * cl_resize --
 306  *      Reset the options for a resize event.
 307  */
 308 static int
 309 cl_resize(SCR *sp, size_t lines, size_t columns)
 310 {
 311         ARGS *argv[2], a, b;
 312         CHAR_T b1[1024];
 313
 314         a.bp = b1;
 315         b.bp = NULL;
 316         a.len = b.len = 0;
 317         argv[0] = &a;
 318         argv[1] = &b;
 319
 320         a.len = SPRINTF(b1, sizeof(b1), L("lines=%lu"), (u_long)lines);
 321         if (opts_set(sp, argv, NULL))
 322                 return (1);
 323         a.len = SPRINTF(b1, sizeof(b1), L("columns=%lu"), (u_long)columns);
 324         if (opts_set(sp, argv, NULL))
 325                 return (1);
 326         return (0);
 327 }