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