1 /* $NetBSD: getusershell.c,v 1.6 1997/07/13 19:46:02 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1985, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)getusershell.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: getusershell.c,v 1.6 1997/07/13 19:46:02 christos Exp $"); 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 #include <sys/param.h> 46 #include <sys/file.h> 47 #include <sys/stat.h> 48 #include <stdio.h> 49 #include <ctype.h> 50 #include <stdlib.h> 51 #include <unistd.h> 52 #include <paths.h> 53 54 /* 55 * Local shells should NOT be added here. They should be added in 56 * /etc/shells. 57 */ 58 59 static char *okshells[] = { _PATH_BSHELL, _PATH_CSHELL, NULL }; 60 static char **curshell, **shells, *strings; 61 static char **initshells __P((void)); 62 63 /* 64 * Get a list of shells from _PATH_SHELLS, if it exists. 65 */ 66 char * 67 getusershell() 68 { 69 char *ret; 70 71 if (curshell == NULL) 72 curshell = initshells(); 73 ret = *curshell; 74 if (ret != NULL) 75 curshell++; 76 return (ret); 77 } 78 79 void 80 endusershell() 81 { 82 83 if (shells != NULL) 84 free(shells); 85 shells = NULL; 86 if (strings != NULL) 87 free(strings); 88 strings = NULL; 89 curshell = NULL; 90 } 91 92 void 93 setusershell() 94 { 95 96 curshell = initshells(); 97 } 98 99 static char ** 100 initshells() 101 { 102 register char **sp, *cp; 103 register FILE *fp; 104 struct stat statb; 105 106 if (shells != NULL) 107 free(shells); 108 shells = NULL; 109 if (strings != NULL) 110 free(strings); 111 strings = NULL; 112 if ((fp = fopen(_PATH_SHELLS, "r")) == NULL) 113 return (okshells); 114 if (fstat(fileno(fp), &statb) == -1) { 115 (void)fclose(fp); 116 return (okshells); 117 } 118 if ((strings = malloc((u_int)statb.st_size)) == NULL) { 119 (void)fclose(fp); 120 return (okshells); 121 } 122 shells = calloc((unsigned)statb.st_size / 3, sizeof (char *)); 123 if (shells == NULL) { 124 (void)fclose(fp); 125 free(strings); 126 strings = NULL; 127 return (okshells); 128 } 129 sp = shells; 130 cp = strings; 131 while (fgets(cp, MAXPATHLEN + 1, fp) != NULL) { 132 while (*cp != '#' && *cp != '/' && *cp != '\0') 133 cp++; 134 if (*cp == '#' || *cp == '\0') 135 continue; 136 *sp++ = cp; 137 while (!isspace(*cp) && *cp != '#' && *cp != '\0') 138 cp++; 139 *cp++ = '\0'; 140 } 141 *sp = NULL; 142 (void)fclose(fp); 143 return (shells); 144 } 145