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 #ifndef lint
  13 static const char sccsid[] = "$Id: cl_read.c,v 10.30 2012/07/12 18:28:58 zy Exp $";
  14 #endif /* not lint */
  15
  16 #include <sys/types.h>
  17 #include <sys/queue.h>
  18 #include <sys/select.h>
  19
  20 #include <bitstring.h>
  21 #include <errno.h>
  22 #include <fcntl.h>
  23 #include <signal.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <termios.h>
  28 #include <unistd.h>
  29
  30 #include "../common/common.h"
  31 #include "../ex/script.h"
  32 #include "cl.h"
  33
  34 /* Pollution by Solaris curses. */
  35 #undef columns
  36 #undef lines
  37
  38 static input_t  cl_read(SCR *,
  39     u_int32_t, char *, size_t, int *, struct timeval *);
  40 static int      cl_resize(SCR *, size_t, size_t);
  41
  42 /*
  43  * cl_event --
  44  *      Return a single event.
  45  *
  46  * PUBLIC: int cl_event(SCR *, EVENT *, u_int32_t, int);
  47  */
  48 int
  49 cl_event(SCR *sp, EVENT *evp, u_int32_t flags, int ms)
  50 {
  51         struct timeval t, *tp;
  52         CL_PRIVATE *clp;
  53         size_t lines, columns;
  54         int changed, nr = 0;
  55         CHAR_T *wp;
  56         size_t wlen;
  57         int rc;
  58
  59         /*
  60          * Queue signal based events.  We never clear SIGHUP or SIGTERM events,
  61          * so that we just keep returning them until the editor dies.
  62          */
  63         clp = CLP(sp);
  64 retest: if (LF_ISSET(EC_INTERRUPT) || F_ISSET(clp, CL_SIGINT)) {
  65                 if (F_ISSET(clp, CL_SIGINT)) {
  66                         F_CLR(clp, CL_SIGINT);
  67                         evp->e_event = E_INTERRUPT;
  68                 } else
  69                         evp->e_event = E_TIMEOUT;
  70                 return (0);
  71         }
  72         if (F_ISSET(clp, CL_SIGHUP | CL_SIGTERM | CL_SIGWINCH)) {
  73                 if (F_ISSET(clp, CL_SIGHUP)) {
  74                         evp->e_event = E_SIGHUP;
  75                         return (0);
  76                 }
  77                 if (F_ISSET(clp, CL_SIGTERM)) {
  78                         evp->e_event = E_SIGTERM;
  79                         return (0);
  80                 }
  81                 if (F_ISSET(clp, CL_SIGWINCH)) {
  82                         F_CLR(clp, CL_SIGWINCH);
  83                         if (cl_ssize(sp, 1, &lines, &columns, &changed))
  84                                 return (1);
  85                         if (changed) {
  86                                 (void)cl_resize(sp, lines, columns);
  87                                 evp->e_event = E_WRESIZE;
  88                                 return (0);
  89                         }
  90                         /* No real change, ignore the signal. */
  91                 }
  92         }
  93
  94         /* Set timer. */
  95         if (ms == 0)
  96                 tp = NULL;
  97         else {
  98                 t.tv_sec = ms / 1000;
  99                 t.tv_usec = (ms % 1000) * 1000;
 100                 tp = &t;
 101         }
 102
 103         /* Read input characters. */
 104 read:
 105         switch (cl_read(sp, LF_ISSET(EC_QUOTED | EC_RAW),
 106             clp->ibuf + clp->skip, SIZE(clp->ibuf) - clp->skip, &nr, tp)) {
 107         case INP_OK:
 108                 rc = INPUT2INT5(sp, clp->cw, clp->ibuf, nr + clp->skip,
 109                                 wp, wlen);
 110                 evp->e_csp = wp;
 111                 evp->e_len = wlen;
 112                 evp->e_event = E_STRING;
 113                 if (rc < 0) {
 114                     int n = -rc;
 115                     memmove(clp->ibuf, clp->ibuf + nr + clp->skip - n, n);
 116                     clp->skip = n;
 117                     if (wlen == 0)
 118                         goto read;
 119                 } else if (rc == 0)
 120                     clp->skip = 0;
 121                 else
 122                     msgq(sp, M_ERR, "323|Invalid input. Truncated.");
 123                 break;
 124         case INP_EOF:
 125                 evp->e_event = E_EOF;
 126                 break;
 127         case INP_ERR:
 128                 evp->e_event = E_ERR;
 129                 break;
 130         case INP_INTR:
 131                 goto retest;
 132         case INP_TIMEOUT:
 133                 evp->e_event = E_TIMEOUT;
 134                 break;
 135         default:
 136                 abort();
 137         }
 138         return (0);
 139 }
 140
 141 /*
 142  * cl_read --
 143  *      Read characters from the input.
 144  */
 145 static input_t
 146 cl_read(SCR *sp, u_int32_t flags, char *bp, size_t blen, int *nrp,
 147     struct timeval *tp)
 148 {
 149         struct termios term1, term2;
 150         CL_PRIVATE *clp;
 151         GS *gp;
 152         fd_set rdfd;
 153         input_t rval;
 154         int maxfd, nr, term_reset;
 155
 156         gp = sp->gp;
 157         clp = CLP(sp);
 158         term_reset = 0;
 159
 160         /*
 161          * 1: A read from a file or a pipe.  In this case, the reads
 162          *    never timeout regardless.  This means that we can hang
 163          *    when trying to complete a map, but we're going to hang
 164          *    on the next read anyway.
 165          */
 166         if (!F_ISSET(clp, CL_STDIN_TTY)) {
 167                 switch (nr = read(STDIN_FILENO, bp, blen)) {
 168                 case 0:
 169                         return (INP_EOF);
 170                 case -1:
 171                         goto err;
 172                 default:
 173                         *nrp = nr;
 174                         return (INP_OK);
 175                 }
 176                 /* NOTREACHED */
 177         }
 178
 179         /*
 180          * 2: A read with an associated timeout, e.g., trying to complete
 181          *    a map sequence.  If input exists, we fall into #3.
 182          */
 183         if (tp != NULL) {
 184                 FD_ZERO(&rdfd);
 185                 FD_SET(STDIN_FILENO, &rdfd);
 186                 switch (select(STDIN_FILENO + 1, &rdfd, NULL, NULL, tp)) {
 187                 case 0:
 188                         return (INP_TIMEOUT);
 189                 case -1:
 190                         goto err;
 191                 default:
 192                         break;
 193                 }
 194         }
 195
 196         /*
 197          * The user can enter a key in the editor to quote a character.  If we
 198          * get here and the next key is supposed to be quoted, do what we can.
 199          * Reset the tty so that the user can enter a ^C, ^Q, ^S.  There's an
 200          * obvious race here, when the key has already been entered, but there's
 201          * nothing that we can do to fix that problem.
 202          *
 203          * The editor can ask for the next literal character even thought it's
 204          * generally running in line-at-a-time mode.  Do what we can.
 205          */
 206         if (LF_ISSET(EC_QUOTED | EC_RAW) && !tcgetattr(STDIN_FILENO, &term1)) {
 207                 term_reset = 1;
 208                 if (LF_ISSET(EC_QUOTED)) {
 209                         term2 = term1;
 210                         term2.c_lflag &= ~ISIG;
 211                         term2.c_iflag &= ~(IXON | IXOFF);
 212                         (void)tcsetattr(STDIN_FILENO,
 213                             TCSASOFT | TCSADRAIN, &term2);
 214                 } else
 215                         (void)tcsetattr(STDIN_FILENO,
 216                             TCSASOFT | TCSADRAIN, &clp->vi_enter);
 217         }
 218
 219         /*
 220          * 3: Wait for input.
 221          *
 222          * Select on the command input and scripting window file descriptors.
 223          * It's ugly that we wait on scripting file descriptors here, but it's
 224          * the only way to keep from locking out scripting windows.
 225          */
 226         if (F_ISSET(gp, G_SCRWIN)) {
 227 loop:           FD_ZERO(&rdfd);
 228                 FD_SET(STDIN_FILENO, &rdfd);
 229                 maxfd = STDIN_FILENO;
 230                 if (F_ISSET(sp, SC_SCRIPT)) {
 231                         FD_SET(sp->script->sh_master, &rdfd);
 232                         if (sp->script->sh_master > maxfd)
 233                                 maxfd = sp->script->sh_master;
 234                 }
 235                 switch (select(maxfd + 1, &rdfd, NULL, NULL, NULL)) {
 236                 case 0:
 237                         abort();
 238                 case -1:
 239                         goto err;
 240                 default:
 241                         break;
 242                 }
 243                 if (!FD_ISSET(STDIN_FILENO, &rdfd)) {
 244                         if (sscr_input(sp))
 245                                 return (INP_ERR);
 246                         goto loop;
 247                 }
 248         }
 249
 250         /*
 251          * 4: Read the input.
 252          *
 253          * !!!
 254          * What's going on here is some scary stuff.  Ex runs the terminal in
 255          * canonical mode.  So, the <newline> character terminating a line of
 256          * input is returned in the buffer, but a trailing <EOF> character is
 257          * not similarly included.  As ex uses 0<EOF> and ^<EOF> as autoindent
 258          * commands, it has to see the trailing <EOF> characters to determine
 259          * the difference between the user entering "0ab" and "0<EOF>ab".  We
 260          * leave an extra slot in the buffer, so that we can add a trailing
 261          * <EOF> character if the buffer isn't terminated by a <newline>.  We
 262          * lose if the buffer is too small for the line and exactly N characters
 263          * are entered followed by an <EOF> character.
 264          */
 265 #define ONE_FOR_EOF     1
 266         switch (nr = read(STDIN_FILENO, bp, blen - ONE_FOR_EOF)) {
 267         case  0:                                /* EOF. */
 268                 /*
 269                  * ^D in canonical mode returns a read of 0, i.e. EOF.  EOF is
 270                  * a valid command, but we don't want to loop forever because
 271                  * the terminal driver is returning EOF because the user has
 272                  * disconnected. The editor will almost certainly try to write
 273                  * something before this fires, which should kill us, but You
 274                  * Never Know.
 275                  */
 276                 if (++clp->eof_count < 50) {
 277                         bp[0] = clp->orig.c_cc[VEOF];
 278                         *nrp = 1;
 279                         rval = INP_OK;
 280
 281                 } else
 282                         rval = INP_EOF;
 283                 break;
 284         case -1:                                /* Error or interrupt. */
 285 err:            if (errno == EINTR)
 286                         rval = INP_INTR;
 287                 else {
 288                         rval = INP_ERR;
 289                         msgq(sp, M_SYSERR, "input");
 290                 }
 291                 break;
 292         default:                                /* Input characters. */
 293                 if (F_ISSET(sp, SC_EX) && bp[nr - 1] != '\n')
 294                         bp[nr++] = clp->orig.c_cc[VEOF];
 295                 *nrp = nr;
 296                 clp->eof_count = 0;
 297                 rval = INP_OK;
 298                 break;
 299         }
 300
 301         /* Restore the terminal state if it was modified. */
 302         if (term_reset)
 303                 (void)tcsetattr(STDIN_FILENO, TCSASOFT | TCSADRAIN, &term1);
 304         return (rval);
 305 }
 306
 307 /*
 308  * cl_resize --
 309  *      Reset the options for a resize event.
 310  */
 311 static int
 312 cl_resize(SCR *sp, size_t lines, size_t columns)
 313 {
 314         ARGS *argv[2], a, b;
 315         CHAR_T b1[1024];
 316
 317         a.bp = b1;
 318         b.bp = NULL;
 319         a.len = b.len = 0;
 320         argv[0] = &a;
 321         argv[1] = &b;
 322
 323         a.len = SPRINTF(b1, sizeof(b1), L("lines=%lu"), (u_long)lines);
 324         if (opts_set(sp, argv, NULL))
 325                 return (1);
 326         a.len = SPRINTF(b1, sizeof(b1), L("columns=%lu"), (u_long)columns);
 327         if (opts_set(sp, argv, NULL))
 328                 return (1);
 329         return (0);
 330 }