1 /* 2 * Copyright (c) 1988 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software written by Ken Arnold and 6 * published in UNIX Review, Vol. 6, No. 8. 7 * 8 * Redistribution and use in source and binary forms are permitted 9 * provided that the above copyright notice and this paragraph are 10 * duplicated in all such forms and that any documentation, 11 * advertising materials, and other materials related to such 12 * distribution and use acknowledge that the software was developed 13 * by the University of California, Berkeley. The name of the 14 * University may not be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 18 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 19 * 20 * static char sccsid[] = "@(#)popen.c 5.7 (Berkeley) 9/1/88"; 21 */ 22 23 #ifndef lint 24 static char sccsid[] = "@(#)popen.c 5.6 (Berkeley) 12/19/88"; 25 #endif /* not lint */ 26 27 #include <sys/types.h> 28 #include <sys/signal.h> 29 #include <sys/wait.h> 30 #include <stdio.h> 31 32 /* 33 * Special version of popen which avoids call to shell. This insures noone 34 * may create a pipe to a hidden program as a side effect of a list or dir 35 * command. 36 */ 37 static int *pids; 38 static int fds; 39 40 FILE * 41 ftpd_popen(program, type) 42 char *program, *type; 43 { 44 register char *cp; 45 FILE *iop; 46 int argc, gargc, pdes[2], pid; 47 char **pop, *argv[100], *gargv[1000], *vv[2]; 48 extern char **glob(), **copyblk(), *strtok(), *malloc(); 49 50 if (*type != 'r' && *type != 'w' || type[1]) 51 return(NULL); 52 53 if (!pids) { 54 if ((fds = getdtablesize()) <= 0) 55 return(NULL); 56 if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL) 57 return(NULL); 58 bzero((char *)pids, fds * sizeof(int)); 59 } 60 if (pipe(pdes) < 0) 61 return(NULL); 62 63 /* break up string into pieces */ 64 for (argc = 0, cp = program;; cp = NULL) 65 if (!(argv[argc++] = strtok(cp, " \t\n"))) 66 break; 67 68 /* glob each piece */ 69 gargv[0] = argv[0]; 70 for (gargc = argc = 1; argv[argc]; argc++) { 71 if (!(pop = glob(argv[argc]))) { /* globbing failed */ 72 vv[0] = argv[argc]; 73 vv[1] = NULL; 74 pop = copyblk(vv); 75 } 76 argv[argc] = (char *)pop; /* save to free later */ 77 while (*pop && gargc < 1000) 78 gargv[gargc++] = *pop++; 79 } 80 gargv[gargc] = NULL; 81 82 iop = NULL; 83 switch(pid = vfork()) { 84 case -1: /* error */ 85 (void)close(pdes[0]); 86 (void)close(pdes[1]); 87 goto pfree; 88 /* NOTREACHED */ 89 case 0: /* child */ 90 if (*type == 'r') { 91 if (pdes[1] != 1) { 92 dup2(pdes[1], 1); 93 dup2(pdes[1], 2); /* stderr, too! */ 94 (void)close(pdes[1]); 95 } 96 (void)close(pdes[0]); 97 } else { 98 if (pdes[0] != 0) { 99 dup2(pdes[0], 0); 100 (void)close(pdes[0]); 101 } 102 (void)close(pdes[1]); 103 } 104 execv(gargv[0], gargv); 105 _exit(1); 106 } 107 /* parent; assume fdopen can't fail... */ 108 if (*type == 'r') { 109 iop = fdopen(pdes[0], type); 110 (void)close(pdes[1]); 111 } else { 112 iop = fdopen(pdes[1], type); 113 (void)close(pdes[0]); 114 } 115 pids[fileno(iop)] = pid; 116 117 pfree: for (argc = 1; argv[argc] != NULL; argc++) { 118 blkfree((char **)argv[argc]); 119 free((char *)argv[argc]); 120 } 121 return(iop); 122 } 123 124 ftpd_pclose(iop) 125 FILE *iop; 126 { 127 register int fdes; 128 int omask; 129 union wait stat_loc; 130 int pid; 131 132 /* 133 * pclose returns -1 if stream is not associated with a 134 * `popened' command, or, if already `pclosed'. 135 */ 136 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 137 return(-1); 138 (void)fclose(iop); 139 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); 140 while ((pid = wait(&stat_loc)) != pids[fdes] && pid != -1); 141 (void)sigsetmask(omask); 142 pids[fdes] = 0; 143 return(pid == -1 ? -1 : stat_loc.w_status); 144 } 145