/************************************************************************* * (C) 2013 AITNET ltd - Sofia/Bulgaria - * by Michael Pounov * * $Author: misho $ * $Id: pio.c,v 1.8 2020/06/19 23:07:20 misho Exp $ * ************************************************************************** The ELWIX and AITNET software is distributed under the following terms: All of the documentation and software included in the ELWIX and AITNET Releases is copyrighted by ELWIX - Sofia/Bulgaria Copyright 2004 - 2020 by Michael Pounov . All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. All advertising materials mentioning features or use of this software must display the following acknowledgement: This product includes software developed by Michael Pounov ELWIX - Embedded LightWeight unIX and its contributors. 4. Neither the name of AITNET nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY AITNET AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include "global.h" extern char **environ; pio_pid_t pio_pidlist = SLIST_HEAD_INITIALIZER(pio_pidlist); #ifdef HAVE_LIBPTHREAD static pthread_mutex_t pidlist_mutex = PTHREAD_MUTEX_INITIALIZER; #define THREAD_LOCK() pthread_mutex_lock(&pidlist_mutex) #define THREAD_UNLOCK() pthread_mutex_unlock(&pidlist_mutex) #else #define THREAD_LOCK() #define THREAD_UNLOCK() #endif /* * e_popen() - ELWIX replacement of standard popen * * @command = command * @type = type * @ppid = return pid of child program * If value of *ppid is -1 when invoke routine then child will be session leader * return: NULL error or !=NULL open program */ #ifdef POPEN_STREAM FILE * #else int #endif e_popen(const char *command, const char *type, pid_t *ppid) { return e_popen2(command, type, ppid, NULL, 0); } /* * e_popen2() - ELWIX replacement of standard popen with post close of chosen handles * * @command = command * @type = type * @ppid = return pid of child program * If value of *ppid is -1 when invoke routine then child will be session leader * @fds = file descriptor array for close when fork * @fdslen = fds number of descriptors * return: NULL error or !=NULL open program */ #ifdef POPEN_STREAM FILE * #else int #endif e_popen2(const char *command, const char *type, pid_t *ppid, int *fds, size_t fdslen) { struct tagPIOPID *cur, *p; int pdes[2], pid, twoway, cloexec, i; char *argv[4]; if (!command || !type) #ifdef POPEN_STREAM return NULL; #else return -1; #endif cloexec = strchr(type, 'e') != NULL; /* * Lite2 introduced two-way popen() pipes using _socketpair(). * FreeBSD's pipe() is bidirectional, so we use that. */ if (strchr(type, '+')) { twoway = 1; type = "r+"; } else { twoway = 0; if ((*type != 'r' && *type != 'w') || (type[1] && (type[1] != 'e' || type[2]))) #ifdef POPEN_STREAM return NULL; #else return -1; #endif } if (socketpair(AF_UNIX, SOCK_STREAM | (cloexec ? O_CLOEXEC : 0), 0, pdes) < 0) { LOGERR; #ifdef POPEN_STREAM return NULL; #else return -1; #endif } if (!(cur = e_malloc(sizeof(struct tagPIOPID)))) { close(pdes[0]); close(pdes[1]); #ifdef POPEN_STREAM return NULL; #else return -1; #endif } argv[0] = "sh"; argv[1] = "-c"; argv[2] = (char *) command; argv[3] = NULL; THREAD_LOCK(); switch (pid = vfork()) { case -1: /* Error. */ LOGERR; THREAD_UNLOCK(); close(pdes[0]); close(pdes[1]); e_free(cur); #ifdef POPEN_STREAM return NULL; #else return -1; #endif /* NOTREACHED */ case 0: /* Child. */ if (ppid && *ppid == -1) setsid(); if (fds && fdslen) { for (i = 0; i < fdslen; i++) close(fds[i]); } if (*type == 'r') { /* * The _dup2() to STDIN_FILENO is repeated to avoid * writing to pdes[1], which might corrupt the * parent's copy. This isn't good enough in * general, since the _exit() is no return, so * the compiler is free to corrupt all the local * variables. */ if (!cloexec) close(pdes[0]); if (pdes[1] != STDOUT_FILENO) { dup2(pdes[1], STDOUT_FILENO); if (!cloexec) close(pdes[1]); if (twoway) dup2(STDOUT_FILENO, STDIN_FILENO); } else if (twoway && (pdes[1] != STDIN_FILENO)) { dup2(pdes[1], STDIN_FILENO); if (cloexec) fcntl(pdes[1], F_SETFD, 0); } else if (cloexec) fcntl(pdes[1], F_SETFD, 0); } else { if (pdes[0] != STDIN_FILENO) { dup2(pdes[0], STDIN_FILENO); if (!cloexec) close(pdes[0]); } else if (cloexec) fcntl(pdes[0], F_SETFD, 0); if (!cloexec) close(pdes[1]); } SLIST_FOREACH(p, &pio_pidlist, next) #ifdef POPEN_STREAM close(fileno(p->f.fp)); #else close(p->f.fd); #endif execve(_PATH_BSHELL, argv, environ); _exit(127); /* NOTREACHED */ default: if (ppid) *ppid = pid; } THREAD_UNLOCK(); /* Parent; assume fdopen can't fail. */ if (*type == 'r') { #ifdef POPEN_STREAM cur->f.fp = fdopen(pdes[0], type); #else cur->f.fd = pdes[0]; #endif close(pdes[1]); } else { #ifdef POPEN_STREAM cur->f.fp = fdopen(pdes[1], type); #else cur->f.fd = pdes[1]; #endif close(pdes[0]); } /* Link into list of file descriptors. */ cur->pid = pid; THREAD_LOCK(); SLIST_INSERT_HEAD(&pio_pidlist, cur, next); THREAD_UNLOCK(); #ifdef POPEN_STREAM return cur->f.fp; #else return cur->f.fd; #endif } /* * e_pclose() - ELWIX replacement of standard pclose * * @iop = popen handle * return: -1 error or !=-1 pid status */ int #ifdef POPEN_STREAM e_pclose(FILE *iop) #else e_pclose(int iop) #endif { struct tagPIOPID *cur, *last = NULL; int pstat = 0; pid_t pid; if (!iop) return -1; /* * Find the appropriate file pointer and remove it from the list. */ THREAD_LOCK(); SLIST_FOREACH(cur, &pio_pidlist, next) { #ifdef POPEN_STREAM if (cur->f.fp == iop) #else if (cur->f.fd == iop) #endif break; last = cur; } if (!cur) { THREAD_UNLOCK(); return (-1); } if (!last) SLIST_REMOVE_HEAD(&pio_pidlist, next); else SLIST_REMOVE_AFTER(last, next); THREAD_UNLOCK(); #ifdef POPEN_STREAM fclose(iop); #else close(iop); #endif do { pid = wait4(cur->pid, &pstat, 0, NULL); } while (pid == -1 && errno == EINTR); e_free(cur); return (pid == -1 ? -1 : pstat); } /* * pio_pgetpid() - Get tagPIOPID structure from file handle * * @iop = popen handle * return: NULL error or !=NULL tagPIOPID structure */ struct tagPIOPID * #ifdef POPEN_STREAM pio_pgetpid(FILE *iop) #else pio_pgetpid(int iop) #endif { struct tagPIOPID *p; if (!iop) return NULL; THREAD_LOCK(); SLIST_FOREACH(p, &pio_pidlist, next) #ifdef POPEN_STREAM if (p->f.fp == iop) #else if (p->f.fd == iop) #endif break; THREAD_UNLOCK(); return p; } /* * pio_pchkpid() - Check exit status of child programs * * @pids = return tagPIOPID structures of exited programs, * if !=NULL must call array_Destroy() * return: -1 error or >-1 exited programs */ int pio_pchkpid(array_t ** __restrict pids) { register int ret = 0; struct tagPIOPID *p; array_t *pa = NULL; if (pids) { if (!(pa = array_Init(0))) return -1; else *pids = pa; } THREAD_LOCK(); SLIST_FOREACH(p, &pio_pidlist, next) #ifdef POPEN_STREAM if (p->f.fp && waitpid(p->pid, &p->stat, WNOHANG) > 0) { #else if (p->f.fd && waitpid(p->pid, &p->stat, WNOHANG) > 0) { #endif if (pids) array_Push(pa, p, 0); ret++; } THREAD_UNLOCK(); return ret; }