contrib/nvi2/ex/ex_shell.c

   1 /*-
   2  * Copyright (c) 1992, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 1992, 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: ex_shell.c,v 10.44 2012/07/06 06:51:26 zy Exp $";
  14 #endif /* not lint */
  15
  16 #include <sys/queue.h>
  17 #include <sys/time.h>
  18 #include <sys/wait.h>
  19
  20 #include <bitstring.h>
  21 #include <ctype.h>
  22 #include <errno.h>
  23 #include <limits.h>
  24 #include <signal.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <unistd.h>
  29
  30 #include "../common/common.h"
  31
  32 static const char *sigmsg(int);
  33
  34 /*
  35  * ex_shell -- :sh[ell]
  36  *      Invoke the program named in the SHELL environment variable
  37  *      with the argument -i.
  38  *
  39  * PUBLIC: int ex_shell(SCR *, EXCMD *);
  40  */
  41 int
  42 ex_shell(SCR *sp, EXCMD *cmdp)
  43 {
  44         int rval;
  45         char *buf;
  46
  47         /* We'll need a shell. */
  48         if (opts_empty(sp, O_SHELL, 0))
  49                 return (1);
  50
  51         /*
  52          * XXX
  53          * Assumes all shells use -i.
  54          */
  55         (void)asprintf(&buf, "%s -i", O_STR(sp, O_SHELL));
  56         if (buf == NULL) {
  57                 msgq(sp, M_SYSERR, NULL);
  58                 return (1);
  59         }
  60
  61         /* Restore the window name. */
  62         (void)sp->gp->scr_rename(sp, NULL, 0);
  63
  64         /* If we're still in a vi screen, move out explicitly. */
  65         rval = ex_exec_proc(sp, cmdp, buf, NULL, !F_ISSET(sp, SC_SCR_EXWROTE));
  66         free(buf);
  67
  68         /* Set the window name. */
  69         (void)sp->gp->scr_rename(sp, sp->frp->name, 1);
  70
  71         /*
  72          * !!!
  73          * Historically, vi didn't require a continue message after the
  74          * return of the shell.  Match it.
  75          */
  76         F_SET(sp, SC_EX_WAIT_NO);
  77
  78         return (rval);
  79 }
  80
  81 /*
  82  * ex_exec_proc --
  83  *      Run a separate process.
  84  *
  85  * PUBLIC: int ex_exec_proc(SCR *, EXCMD *, char *, const char *, int);
  86  */
  87 int
  88 ex_exec_proc(SCR *sp, EXCMD *cmdp, char *cmd, const char *msg, int need_newline)
  89 {
  90         GS *gp;
  91         const char *name;
  92         pid_t pid;
  93
  94         gp = sp->gp;
  95
  96         /* We'll need a shell. */
  97         if (opts_empty(sp, O_SHELL, 0))
  98                 return (1);
  99
 100         /* Enter ex mode. */
 101         if (F_ISSET(sp, SC_VI)) {
 102                 if (gp->scr_screen(sp, SC_EX)) {
 103                         ex_wemsg(sp, cmdp->cmd->name, EXM_NOCANON);
 104                         return (1);
 105                 }
 106                 (void)gp->scr_attr(sp, SA_ALTERNATE, 0);
 107                 F_SET(sp, SC_SCR_EX | SC_SCR_EXWROTE);
 108         }
 109
 110         /* Put out additional newline, message. */
 111         if (need_newline)
 112                 (void)ex_puts(sp, "\n");
 113         if (msg != NULL) {
 114                 (void)ex_puts(sp, msg);
 115                 (void)ex_puts(sp, "\n");
 116         }
 117         (void)ex_fflush(sp);
 118
 119         switch (pid = vfork()) {
 120         case -1:                        /* Error. */
 121                 msgq(sp, M_SYSERR, "vfork");
 122                 return (1);
 123         case 0:                         /* Utility. */
 124                 if (gp->scr_child)
 125                         gp->scr_child(sp);
 126                 if ((name = strrchr(O_STR(sp, O_SHELL), '/')) == NULL)
 127                         name = O_STR(sp, O_SHELL);
 128                 else
 129                         ++name;
 130                 execl(O_STR(sp, O_SHELL), name, "-c", cmd, (char *)NULL);
 131                 msgq_str(sp, M_SYSERR, O_STR(sp, O_SHELL), "execl: %s");
 132                 _exit(127);
 133                 /* NOTREACHED */
 134         default:                        /* Parent. */
 135                 return (proc_wait(sp, (long)pid, cmd, 0, 0));
 136         }
 137         /* NOTREACHED */
 138 }
 139
 140 /*
 141  * proc_wait --
 142  *      Wait for one of the processes.
 143  *
 144  * !!!
 145  * The pid_t type varies in size from a short to a long depending on the
 146  * system.  It has to be cast into something or the standard promotion
 147  * rules get you.  I'm using a long based on the belief that nobody is
 148  * going to make it unsigned and it's unlikely to be a quad.
 149  *
 150  * PUBLIC: int proc_wait(SCR *, long, const char *, int, int);
 151  */
 152 int
 153 proc_wait(SCR *sp, long int pid, const char *cmd, int silent, int okpipe)
 154 {
 155         size_t len;
 156         int nf, pstat;
 157         char *p;
 158
 159         /* Wait for the utility, ignoring interruptions. */
 160         for (;;) {
 161                 errno = 0;
 162                 if (waitpid((pid_t)pid, &pstat, 0) != -1)
 163                         break;
 164                 if (errno != EINTR) {
 165                         msgq(sp, M_SYSERR, "waitpid");
 166                         return (1);
 167                 }
 168         }
 169
 170         /*
 171          * Display the utility's exit status.  Ignore SIGPIPE from the
 172          * parent-writer, as that only means that the utility chose to
 173          * exit before reading all of its input.
 174          */
 175         if (WIFSIGNALED(pstat) && (!okpipe || WTERMSIG(pstat) != SIGPIPE)) {
 176                 for (; cmdskip(*cmd); ++cmd);
 177                 p = msg_print(sp, cmd, &nf);
 178                 len = strlen(p);
 179                 msgq(sp, M_ERR, "%.*s%s: received signal: %s%s",
 180                     (int)MIN(len, 20), p, len > 20 ? " ..." : "",
 181                     sigmsg(WTERMSIG(pstat)),
 182                     WCOREDUMP(pstat) ? "; core dumped" : "");
 183                 if (nf)
 184                         FREE_SPACE(sp, p, 0);
 185                 return (1);
 186         }
 187
 188         if (WIFEXITED(pstat) && WEXITSTATUS(pstat)) {
 189                 /*
 190                  * Remain silent for "normal" errors when doing shell file
 191                  * name expansions, they almost certainly indicate nothing
 192                  * more than a failure to match.
 193                  *
 194                  * Remain silent for vi read filter errors.  It's historic
 195                  * practice.
 196                  */
 197                 if (!silent) {
 198                         for (; cmdskip(*cmd); ++cmd);
 199                         p = msg_print(sp, cmd, &nf);
 200                         len = strlen(p);
 201                         msgq(sp, M_ERR, "%.*s%s: exited with status %d",
 202                             (int)MIN(len, 20), p, len > 20 ? " ..." : "",
 203                             WEXITSTATUS(pstat));
 204                         if (nf)
 205                                 FREE_SPACE(sp, p, 0);
 206                 }
 207                 return (1);
 208         }
 209         return (0);
 210 }
 211
 212 /*
 213  * sigmsg --
 214  *      Return a pointer to a message describing a signal.
 215  */
 216 static const char *
 217 sigmsg(int signo)
 218 {
 219         static char buf[40];
 220         char *message;
 221
 222         /* POSIX.1-2008 leaves strsignal(3)'s return value unspecified. */
 223         if ((message = strsignal(signo)) != NULL)
 224                 return message;
 225         (void)snprintf(buf, sizeof(buf), "Unknown signal: %d", signo);
 226         return (buf);
 227 }