ipc/ip_run.c

   1 /*-
   2  * Copyright (c) 1996
   3  *      Rob Zimmermann.  All rights reserved.
   4  * Copyright (c) 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: ip_run.c,v 8.17 2000/07/04 21:48:54 skimo Exp $ (Berkeley) $Date: 2000/07/04 21:48:54 $";
  14 #endif /* not lint */
  15
  16 #include <sys/types.h>
  17 #include <sys/queue.h>
  18 #include <sys/stat.h>
  19
  20 #include <bitstring.h>
  21 #include <errno.h>
  22 #include <fcntl.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27
  28 #include <sys/socket.h>
  29
  30 #include "../common/common.h"
  31 #include "ip.h"
  32 #include "pathnames.h"
  33
  34 static void arg_format __P((char *, int *, char **[], int, int));
  35 static void fatal __P((void));
  36 #ifdef DEBUG
  37 static void attach __P((void));
  38 #endif
  39 static int channel(int rpipe[2], int wpipe[2]);
  40
  41 char    *vi_progname = "vi";                    /* Global: program name. */
  42
  43 /*
  44  * vi_run --
  45  *      Run the vi program.
  46  *
  47  * PUBLIC: int vi_run __P((IPVI *, int, char *[]));
  48  */
  49 int
  50 vi_run(ipvi, argc, argv)
  51         IPVI *ipvi;
  52         int argc;
  53         char *argv[];
  54 {
  55         struct stat sb;
  56         int pflag, rpipe[2], wpipe[2];
  57         char *execp, **p_av, **t_av;
  58
  59         pflag = 0;
  60         execp = VI;
  61
  62         /* Strip out any arguments that vi isn't going to understand. */
  63         for (p_av = t_av = argv;;) {
  64                 if (*t_av == NULL) {
  65                         *p_av = NULL;
  66                         break;
  67                 }
  68                 if (!strcmp(*t_av, "--")) {
  69                         while ((*p_av++ = *++t_av) != NULL);
  70                         break;
  71                 }
  72 #ifdef DEBUG
  73                 if (!memcmp(*t_av, "-D", sizeof("-D") - 1)) {
  74                         attach();
  75
  76                         ++t_av;
  77                         --argc;
  78                         continue;
  79                 }
  80 #endif
  81 #ifdef TRACE
  82                 if (!memcmp(*t_av, "-T", sizeof("-T") - 1)) {
  83                         char *p = &t_av[0][sizeof("-T") - 1];
  84                         if (*p == '\0') {
  85                                 --argc;
  86                                 p = *++t_av;
  87                         }
  88                         vtrace_init(p);
  89                         ++t_av;
  90                         --argc;
  91                         continue;
  92                 }
  93 #endif
  94                 if (!memcmp(*t_av, "-P", sizeof("-P") - 1)) {
  95                         if (t_av[0][2] != '\0') {
  96                                 pflag = 1;
  97                                 execp = t_av[0] + 2;
  98                                 ++t_av;
  99                                 --argc;
 100                                 continue;
 101                         }
 102                         if (t_av[1] != NULL) {
 103                                 pflag = 1;
 104                                 execp = t_av[1];
 105                                 t_av += 2;
 106                                 argc -= 2;
 107                                 continue;
 108                         }
 109                 }
 110                 *p_av++ = *t_av++;
 111         }
 112
 113         /*
 114          * Open the communications channels.  The pipes are named from the
 115          * parent's viewpoint, meaning the screen reads from rpipe[0] and
 116          * writes to wpipe[1].  The vi process reads from wpipe[0], and it
 117          * writes to rpipe[1].
 118          */
 119         if (channel(rpipe, wpipe) == -1)
 120                 fatal();
 121         ipvi->ifd = rpipe[0];
 122         ipvi->ofd = wpipe[1];
 123
 124         /*
 125          * Reformat our arguments, adding a -I to the list.  The first file
 126          * descriptor for the -I argument is vi's input, and the second is
 127          * vi's output.
 128          */
 129         arg_format(execp, &argc, &argv, wpipe[0], rpipe[1]);
 130
 131         /* Run vi. */
 132         switch (ipvi->pid = fork()) {
 133         case -1:                                /* Error. */
 134                 fatal();
 135                 /* NOTREACHED */
 136         case 0:                                 /* Child: Vi. */
 137                 (void)close(rpipe[0]);
 138                 (void)close(wpipe[1]);
 139
 140                 /*
 141                  * If the user didn't override the path and there's a local
 142                  * (debugging) nvi, run it, otherwise run the user's path,
 143                  * if specified, else run the compiled in path.
 144                  */
 145                 if (!pflag && stat("vi-ipc", &sb) == 0)
 146                         execv("vi-ipc", argv);
 147                 execv(execp, argv);
 148                 (void)fprintf(stderr,
 149                     "%s: %s %s\n", vi_progname, execp, strerror(errno));
 150                 (void)fprintf(stderr,
 151 #ifdef DEBUG
 152             "usage: %s [-D] [-P vi_program] [-T trace] [vi arguments]\n",
 153 #else
 154             "usage: %s [-P vi_program] [vi arguments]\n",
 155 #endif
 156                     vi_progname);
 157                 _exit (1);
 158         default:                                /* Parent: Screen. */
 159                 (void)close(rpipe[1]);
 160                 (void)close(wpipe[0]);
 161                 break;
 162         }
 163         return (0);
 164 }
 165
 166 /*
 167  * fatal --
 168  *      Fatal error.
 169  */
 170 static void
 171 fatal()
 172 {
 173         (void)fprintf(stderr, "%s: %s\n", vi_progname, strerror(errno));
 174         exit (1);
 175 }
 176
 177 static
 178 int channel(int rpipe[2], int wpipe[2])
 179 {
 180         if (0) {
 181
 182         if (pipe(rpipe) == -1 || pipe(wpipe) == -1)
 183                 return -1;
 184
 185         } else {
 186
 187         int sockets[2];
 188
 189         if (socketpair(AF_LOCAL, SOCK_STREAM, 0, sockets) == -1)
 190                 return -1;
 191
 192         rpipe[0] = sockets[0];
 193         wpipe[0] = sockets[1];
 194         if (((rpipe[1] = dup(sockets[1])) == -1) ||
 195             ((wpipe[1] = dup(sockets[0])) == -1))
 196                 return -1;
 197
 198         }
 199 }
 200
 201 /*
 202  * arg_format --
 203  *      Reformat our arguments to add the -I argument for vi.
 204  */
 205 static void
 206 arg_format(execp, argcp, argvp, i_fd, o_fd)
 207         char *execp, **argvp[];
 208         int *argcp, i_fd, o_fd;
 209 {
 210         char *iarg, **largv, *p, **p_av, **t_av;
 211
 212         /* Get space for the argument array and the -I argument. */
 213         if ((iarg = malloc(64)) == NULL ||
 214             (largv = malloc((*argcp + 3) * sizeof(char *))) == NULL)
 215                 fatal();
 216         memcpy(largv + 2, *argvp, *argcp * sizeof(char *) + 1);
 217
 218         /* Reset argv[0] to be the exec'd program. */
 219         if ((p = strrchr(execp, '/')) == NULL)
 220                 largv[0] = execp;
 221         else
 222                 largv[0] = p + 1;
 223
 224         /* Create the -I argument. */
 225         (void)sprintf(iarg, "-I%d%s%d", i_fd, ".", o_fd);
 226         largv[1] = iarg;
 227
 228         /* Copy any remaining arguments into the array. */
 229         for (p_av = (*argvp) + 1, t_av = largv + 2;;)
 230                 if ((*t_av++ = *p_av++) == NULL)
 231                         break;
 232
 233         /* Reset the argument array. */
 234         *argvp = largv;
 235 }
 236
 237 #ifdef DEBUG
 238 /*
 239  * attach --
 240  *      Pause and let the user attach a debugger.
 241  */
 242 static void
 243 attach()
 244 {
 245         int fd;
 246         char ch;
 247
 248         (void)printf("process %lu waiting, enter <CR> to continue: ",
 249             (u_long)getpid());
 250         (void)fflush(stdout);
 251
 252         if ((fd = open(_PATH_TTY, O_RDONLY, 0)) < 0) {
 253                 (void)fprintf(stderr,
 254                     "%s: %s, %s\n", vi_progname, _PATH_TTY, strerror(errno));
 255                 exit (1);;
 256         }
 257         do {
 258                 if (read(fd, &ch, 1) != 1) {
 259                         (void)close(fd);
 260                         return;
 261                 }
 262         } while (ch != '\n' && ch != '\r');
 263         (void)close(fd);
 264 }
 265 #endif