/* $OpenBSD: setenv.c,v 1.13 2010/08/23 22:31:50 millert Exp $ */ /* * Copyright (c) 1987 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. * 3. 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. */ /* OPENBSD ORIGINAL: lib/libc/stdlib/setenv.c */ #include "includes.h" #if !defined(HAVE_SETENV) || !defined(HAVE_UNSETENV) #include <errno.h> #include <stdlib.h> #include <string.h> extern char **environ; #ifndef HAVE_SETENV static char **lastenv; /* last value of environ */ #endif /* OpenSSH Portable: __findenv is from getenv.c rev 1.8, made static */ /* * __findenv -- * Returns pointer to value associated with name, if any, else NULL. * Starts searching within the environmental array at offset. * Sets offset to be the offset of the name/value combination in the * environmental array, for use by putenv(3), setenv(3) and unsetenv(3). * Explicitly removes '=' in argument name. * * This routine *should* be a static; don't use it. */ static char * __findenv(const char *name, int len, int *offset) { extern char **environ; int i; const char *np; char **p, *cp; if (name == NULL || environ == NULL) return (NULL); for (p = environ + *offset; (cp = *p) != NULL; ++p) { for (np = name, i = len; i && *cp; i--) if (*cp++ != *np++) break; if (i == 0 && *cp++ == '=') { *offset = p - environ; return (cp); } } return (NULL); } #if 0 /* nothing uses putenv */ /* * putenv -- * Add a name=value string directly to the environmental, replacing * any current value. */ int putenv(char *str) { char **P, *cp; size_t cnt; int offset = 0; for (cp = str; *cp && *cp != '='; ++cp) ; if (*cp != '=') { errno = EINVAL; return (-1); /* missing `=' in string */ } if (__findenv(str, (int)(cp - str), &offset) != NULL) { environ[offset++] = str; /* could be set multiple times */ while (__findenv(str, (int)(cp - str), &offset)) { for (P = &environ[offset];; ++P) if (!(*P = *(P + 1))) break; } return (0); } /* create new slot for string */ for (P = environ; *P != NULL; P++) ; cnt = P - environ; P = (char **)realloc(lastenv, sizeof(char *) * (cnt + 2)); if (!P) return (-1); if (lastenv != environ) memcpy(P, environ, cnt * sizeof(char *)); lastenv = environ = P; environ[cnt] = str; environ[cnt + 1] = NULL; return (0); } #endif #ifndef HAVE_SETENV /* * setenv -- * Set the value of the environmental variable "name" to be * "value". If rewrite is set, replace any current value. */ int setenv(const char *name, const char *value, int rewrite) { char *C, **P; const char *np; int l_value, offset = 0; for (np = name; *np && *np != '='; ++np) ; #ifdef notyet if (*np) { errno = EINVAL; return (-1); /* has `=' in name */ } #endif l_value = strlen(value); if ((C = __findenv(name, (int)(np - name), &offset)) != NULL) { int tmpoff = offset + 1; if (!rewrite) return (0); #if 0 /* XXX - existing entry may not be writable */ if (strlen(C) >= l_value) { /* old larger; copy over */ while ((*C++ = *value++)) ; return (0); } #endif /* could be set multiple times */ while (__findenv(name, (int)(np - name), &tmpoff)) { for (P = &environ[tmpoff];; ++P) if (!(*P = *(P + 1))) break; } } else { /* create new slot */ size_t cnt; for (P = environ; *P != NULL; P++) ; cnt = P - environ; P = (char **)realloc(lastenv, sizeof(char *) * (cnt + 2)); if (!P) return (-1); if (lastenv != environ) memcpy(P, environ, cnt * sizeof(char *)); lastenv = environ = P; offset = cnt; environ[cnt + 1] = NULL; } if (!(environ[offset] = /* name + `=' + value */ malloc((size_t)((int)(np - name) + l_value + 2)))) return (-1); for (C = environ[offset]; (*C = *name++) && *C != '='; ++C) ; for (*C++ = '='; (*C++ = *value++); ) ; return (0); } #endif /* HAVE_SETENV */ #ifndef HAVE_UNSETENV /* * unsetenv(name) -- * Delete environmental variable "name". */ int unsetenv(const char *name) { char **P; const char *np; int offset = 0; if (!name || !*name) { errno = EINVAL; return (-1); } for (np = name; *np && *np != '='; ++np) ; if (*np) { errno = EINVAL; return (-1); /* has `=' in name */ } /* could be set multiple times */ while (__findenv(name, (int)(np - name), &offset)) { for (P = &environ[offset];; ++P) if (!(*P = *(P + 1))) break; } return (0); } #endif /* HAVE_UNSETENV */ #endif /* !defined(HAVE_SETENV) || !defined(HAVE_UNSETENV) */
