1 /* $NetBSD: getusershell.c,v 1.5 1995/02/27 04:13:27 cgd 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 #if defined(LIBC_SCCS) && !defined(lint) 37 #if 0 38 static char sccsid[] = "@(#)getusershell.c 8.1 (Berkeley) 6/4/93"; 39 #else 40 static char rcsid[] = "$NetBSD: getusershell.c,v 1.5 1995/02/27 04:13:27 cgd Exp $"; 41 #endif 42 #endif /* LIBC_SCCS and not lint */ 43 44 #include <sys/param.h> 45 #include <sys/file.h> 46 #include <sys/stat.h> 47 #include <stdio.h> 48 #include <ctype.h> 49 #include <stdlib.h> 50 #include <unistd.h> 51 #include <paths.h> 52 53 /* 54 * Local shells should NOT be added here. They should be added in 55 * /etc/shells. 56 */ 57 58 static char *okshells[] = { _PATH_BSHELL, _PATH_CSHELL, NULL }; 59 static char **curshell, **shells, *strings; 60 static char **initshells __P((void)); 61 62 /* 63 * Get a list of shells from _PATH_SHELLS, if it exists. 64 */ 65 char * 66 getusershell() 67 { 68 char *ret; 69 70 if (curshell == NULL) 71 curshell = initshells(); 72 ret = *curshell; 73 if (ret != NULL) 74 curshell++; 75 return (ret); 76 } 77 78 void 79 endusershell() 80 { 81 82 if (shells != NULL) 83 free(shells); 84 shells = NULL; 85 if (strings != NULL) 86 free(strings); 87 strings = NULL; 88 curshell = NULL; 89 } 90 91 void 92 setusershell() 93 { 94 95 curshell = initshells(); 96 } 97 98 static char ** 99 initshells() 100 { 101 register char **sp, *cp; 102 register FILE *fp; 103 struct stat statb; 104 105 if (shells != NULL) 106 free(shells); 107 shells = NULL; 108 if (strings != NULL) 109 free(strings); 110 strings = NULL; 111 if ((fp = fopen(_PATH_SHELLS, "r")) == NULL) 112 return (okshells); 113 if (fstat(fileno(fp), &statb) == -1) { 114 (void)fclose(fp); 115 return (okshells); 116 } 117 if ((strings = malloc((u_int)statb.st_size)) == NULL) { 118 (void)fclose(fp); 119 return (okshells); 120 } 121 shells = calloc((unsigned)statb.st_size / 3, sizeof (char *)); 122 if (shells == NULL) { 123 (void)fclose(fp); 124 free(strings); 125 strings = NULL; 126 return (okshells); 127 } 128 sp = shells; 129 cp = strings; 130 while (fgets(cp, MAXPATHLEN + 1, fp) != NULL) { 131 while (*cp != '#' && *cp != '/' && *cp != '\0') 132 cp++; 133 if (*cp == '#' || *cp == '\0') 134 continue; 135 *sp++ = cp; 136 while (!isspace(*cp) && *cp != '#' && *cp != '\0') 137 cp++; 138 *cp++ = '\0'; 139 } 140 *sp = NULL; 141 (void)fclose(fp); 142 return (shells); 143 } 144