/* * Copyright (c) 1988 The Regents of the University of California. * All rights reserved. * * This code is derived from software written by Ken Arnold and * published in UNIX Review, Vol. 6, No. 8. * * Redistribution and use in source and binary forms are permitted * provided that the above copyright notice and this paragraph are * duplicated in all such forms and that any documentation, * advertising materials, and other materials related to such * distribution and use acknowledge that the software was developed * by the University of California, Berkeley. The name of the * University may not be used to endorse or promote products derived * from this software without specific prior written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. * */ /* this came out of the ftpd sources; it's been modified to avoid the * globbing stuff since we don't need it. also execvp instead of execv. */ #ifndef lint static char rcsid[] = "$Id: popen.c,v 1.1.1.2 1994/01/12 18:38:01 jtc Exp $"; static char sccsid[] = "@(#)popen.c 5.7 (Berkeley) 2/14/89"; #endif /* not lint */ #include "cron.h" #include #define WANT_GLOBBING 0 /* * Special version of popen which avoids call to shell. This insures noone * may create a pipe to a hidden program as a side effect of a list or dir * command. */ static PID_T *pids; static int fds; FILE * cron_popen(program, type) char *program, *type; { register char *cp; FILE *iop; int argc, pdes[2]; PID_T pid; char *argv[100]; #if WANT_GLOBBING char **pop, *vv[2]; int gargc; char *gargv[1000]; extern char **glob(), **copyblk(); #endif if (*type != 'r' && *type != 'w' || type[1]) return(NULL); if (!pids) { if ((fds = getdtablesize()) <= 0) return(NULL); if (!(pids = (PID_T *)malloc((u_int)(fds * sizeof(PID_T))))) return(NULL); bzero((char *)pids, fds * sizeof(PID_T)); } if (pipe(pdes) < 0) return(NULL); /* break up string into pieces */ for (argc = 0, cp = program;; cp = NULL) if (!(argv[argc++] = strtok(cp, " \t\n"))) break; #if WANT_GLOBBING /* glob each piece */ gargv[0] = argv[0]; for (gargc = argc = 1; argv[argc]; argc++) { if (!(pop = glob(argv[argc]))) { /* globbing failed */ vv[0] = argv[argc]; vv[1] = NULL; pop = copyblk(vv); } argv[argc] = (char *)pop; /* save to free later */ while (*pop && gargc < 1000) gargv[gargc++] = *pop++; } gargv[gargc] = NULL; #endif iop = NULL; switch(pid = vfork()) { case -1: /* error */ (void)close(pdes[0]); (void)close(pdes[1]); goto pfree; /* NOTREACHED */ case 0: /* child */ if (*type == 'r') { if (pdes[1] != 1) { dup2(pdes[1], 1); dup2(pdes[1], 2); /* stderr, too! */ (void)close(pdes[1]); } (void)close(pdes[0]); } else { if (pdes[0] != 0) { dup2(pdes[0], 0); (void)close(pdes[0]); } (void)close(pdes[1]); } #if WANT_GLOBBING execvp(gargv[0], gargv); #else execvp(argv[0], argv); #endif _exit(1); } /* parent; assume fdopen can't fail... */ if (*type == 'r') { iop = fdopen(pdes[0], type); (void)close(pdes[1]); } else { iop = fdopen(pdes[1], type); (void)close(pdes[0]); } pids[fileno(iop)] = pid; pfree: #if WANT_GLOBBING for (argc = 1; argv[argc] != NULL; argc++) { /* blkfree((char **)argv[argc]); */ free((char *)argv[argc]); } #endif return(iop); } int cron_pclose(iop) FILE *iop; { register int fdes; int omask; WAIT_T stat_loc; PID_T pid; /* * pclose returns -1 if stream is not associated with a * `popened' command, or, if already `pclosed'. */ if (pids == 0 || pids[fdes = fileno(iop)] == 0) return(-1); (void)fclose(iop); omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); while ((pid = wait(&stat_loc)) != pids[fdes] && pid != -1) ; (void)sigsetmask(omask); pids[fdes] = 0; return (pid == -1 ? -1 : WEXITSTATUS(stat_loc)); }