/* * Copyright (c) 1985, 1993 * The Regents of the University of California. 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. * 4. Neither the name of the University 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 THE REGENTS 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. */ #if defined(LIBC_SCCS) && !defined(lint) static char sccsid[] = "@(#)getusershell.c 8.1 (Berkeley) 6/4/93"; #endif /* LIBC_SCCS and not lint */ #include <sys/param.h> #include <sys/file.h> #include <sys/stat.h> #include <stdio.h> #include <stdio_ext.h> #include <ctype.h> #include <stdlib.h> #include <unistd.h> #include <paths.h> /* * Local shells should NOT be added here. They should be added in * /etc/shells. */ /* NB: we do not initialize okshells here. The initialization needs relocations. These interfaces are used so rarely that this is not justified. Instead explicitly initialize the array when it is used. */ #if 0 static const char *const okshells[] = { _PATH_BSHELL, _PATH_CSHELL, NULL }; #else static const char *okshells[3]; #endif static char **curshell, **shells, *strings; static char **initshells (void) __THROW; /* * Get a list of shells from _PATH_SHELLS, if it exists. */ char * getusershell (void) { char *ret; if (curshell == NULL) curshell = initshells(); ret = *curshell; if (ret != NULL) curshell++; return (ret); } void endusershell (void) { free(shells); shells = NULL; free(strings); strings = NULL; curshell = NULL; } void setusershell (void) { curshell = initshells(); } static char ** initshells (void) { char **sp, *cp; FILE *fp; struct stat64 statb; size_t flen; free(shells); shells = NULL; free(strings); strings = NULL; if ((fp = fopen(_PATH_SHELLS, "rce")) == NULL) goto init_okshells_noclose; if (fstat64(fileno(fp), &statb) == -1) { init_okshells: (void)fclose(fp); init_okshells_noclose: okshells[0] = _PATH_BSHELL; okshells[1] = _PATH_CSHELL; return (char **) okshells; } if (statb.st_size > ~(size_t)0 / sizeof (char *) * 3) goto init_okshells; flen = statb.st_size + 3; if ((strings = malloc(flen)) == NULL) goto init_okshells; shells = malloc(statb.st_size / 3 * sizeof (char *)); if (shells == NULL) { free(strings); strings = NULL; goto init_okshells; } sp = shells; cp = strings; while (fgets_unlocked(cp, flen - (cp - strings), fp) != NULL) { while (*cp != '#' && *cp != '/' && *cp != '\0') cp++; if (*cp == '#' || *cp == '\0' || cp[1] == '\0') continue; *sp++ = cp; while (!isspace(*cp) && *cp != '#' && *cp != '\0') cp++; *cp++ = '\0'; } *sp = NULL; (void)fclose(fp); return (shells); }