/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License, Version 1.0 only * (the "License"). You may not use this file except in compliance * with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* Copyright (c) 1988 AT&T */ /* All Rights Reserved */ /* * Copyright 2004 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma ident "%Z%%M% %I% %E% SMI" /* * cscope - interactive C symbol cross-reference * * process execution functions */ #include "global.h" #include #include #include #include #include #include #include #define getdtablesize() _NFILE #define MAXARGS 100 /* maximum number of arguments to executed command */ pid_t childpid; /* child's process ID */ static SIGTYPE (*oldsigquit)(); /* old value of quit signal */ static SIGTYPE (*oldsigtstp)(); /* old value of terminal stop signal */ static pid_t myfork(void); static int join(pid_t p); /* * execute forks and executes a program or shell script, waits for it to * finish, and returns its exit code. */ /*VARARGS0*/ int execute(char *path, ...) { va_list ap; char *args[MAXARGS + 1]; int exitcode; int i; char msg[MSGLEN + 1]; pid_t p; /* fork and exec the program or shell script */ exitcurses(); if ((p = myfork()) == 0) { /* close all files except stdin, stdout, and stderr */ for (i = 3; i < getdtablesize() && close(i) == 0; ++i) { ; } /* execute the program or shell script */ va_start(ap, path); for (i = 0; i < MAXARGS && (args[i] = va_arg(ap, char *)) != NULL; ++i) { } va_end(ap); args[i] = NULL; /* in case MAXARGS reached */ args[0] = basename(args[0]); (void) execvp(path, args); /* returns only on failure */ (void) sprintf(msg, "\ncscope: cannot execute %s", path); (void) perror(msg); /* display the reason */ askforreturn(); /* wait until the user sees the message */ exit(1); /* exit the child */ } else { exitcode = join(p); /* parent */ } if (noacttimeout) { (void) fprintf(stderr, "cscope: no activity time out--exiting\n"); myexit(SIGALRM); } entercurses(); return (exitcode); } /* myfork acts like fork but also handles signals */ static pid_t myfork(void) { pid_t p; /* process number */ oldsigtstp = signal(SIGTSTP, SIG_DFL); /* the parent ignores the interrupt and quit signals */ if ((p = fork()) > 0) { childpid = p; oldsigquit = signal(SIGQUIT, SIG_IGN); } /* so they can be used to stop the child */ else if (p == 0) { (void) signal(SIGINT, SIG_DFL); (void) signal(SIGQUIT, SIG_DFL); (void) signal(SIGHUP, SIG_DFL); /* restore hangup default */ } /* check for fork failure */ if (p == -1) { myperror("Cannot fork"); } return (p); } /* join is the compliment of fork */ static int join(pid_t p) { int status; pid_t w; /* wait for the correct child to exit */ do { w = wait(&status); } while (p != -1 && w != p); childpid = 0; /* restore signal handling */ (void) signal(SIGQUIT, oldsigquit); (void) signal(SIGTSTP, oldsigtstp); /* return the child's exit code */ return (status >> 8); }