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    /* $OpenBSD: env.c,v 1.6 2017/04/06 21:12:06 tedu Exp $ */  | 
    
    
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    /*  | 
    
    
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     * Copyright (c) 2016 Ted Unangst <tedu@openbsd.org>  | 
    
    
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     *  | 
    
    
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     * Permission to use, copy, modify, and distribute this software for any  | 
    
    
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     * purpose with or without fee is hereby granted, provided that the above  | 
    
    
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     * copyright notice and this permission notice appear in all copies.  | 
    
    
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     *  | 
    
    
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     * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES  | 
    
    
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     * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF  | 
    
    
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     * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR  | 
    
    
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     * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES  | 
    
    
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     * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN  | 
    
    
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     * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF  | 
    
    
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     * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.  | 
    
    
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     */  | 
    
    
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    #include <sys/types.h>  | 
    
    
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    #include <sys/tree.h>  | 
    
    
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    #include <string.h>  | 
    
    
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    #include <stdio.h>  | 
    
    
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    #include <stdlib.h>  | 
    
    
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    #include <err.h>  | 
    
    
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    #include <unistd.h>  | 
    
    
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    #include <errno.h>  | 
    
    
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    #include "doas.h"  | 
    
    
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    struct envnode { | 
    
    
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    	RB_ENTRY(envnode) node;  | 
    
    
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    	const char *key;  | 
    
    
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    	const char *value;  | 
    
    
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    };  | 
    
    
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    struct env { | 
    
    
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    	RB_HEAD(envtree, envnode) root;  | 
    
    
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    	u_int count;  | 
    
    
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    };  | 
    
    
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    static int  | 
    
    
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    envcmp(struct envnode *a, struct envnode *b)  | 
    
    
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    { | 
    
    
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    	return strcmp(a->key, b->key);  | 
    
    
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    }  | 
    
    
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    RB_GENERATE_STATIC(envtree, envnode, node, envcmp)  | 
    
    
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    static struct envnode *  | 
    
    
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    createnode(const char *key, const char *value)  | 
    
    
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    { | 
    
    
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    	struct envnode *node;  | 
    
    
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    	node = malloc(sizeof(*node));  | 
    
    
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    	if (!node)  | 
    
    
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    		err(1, NULL);  | 
    
    
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    	node->key = strdup(key);  | 
    
    
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    	node->value = strdup(value);  | 
    
    
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    	if (!node->key || !node->value)  | 
    
    
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    		err(1, NULL);  | 
    
    
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    	return node;  | 
    
    
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    }  | 
    
    
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    static void  | 
    
    
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    freenode(struct envnode *node)  | 
    
    
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    { | 
    
    
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    	free((char *)node->key);  | 
    
    
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    	free((char *)node->value);  | 
    
    
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    	free(node);  | 
    
    
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    }  | 
    
    
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    static struct env *  | 
    
    
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    createenv(const struct rule *rule)  | 
    
    
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    { | 
    
    
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    	struct env *env;  | 
    
    
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    	u_int i;  | 
    
    
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    	env = malloc(sizeof(*env));  | 
    
    
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    	if (!env)  | 
    
    
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    		err(1, NULL);  | 
    
    
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    	RB_INIT(&env->root);  | 
    
    
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    	env->count = 0;  | 
    
    
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    	if (rule->options & KEEPENV) { | 
    
    
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    		extern const char **environ;  | 
    
    
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    		for (i = 0; environ[i] != NULL; i++) { | 
    
    
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    			struct envnode *node;  | 
    
    
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    			const char *e, *eq;  | 
    
    
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    			size_t len;  | 
    
    
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    			char name[1024];  | 
    
    
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    			e = environ[i];  | 
    
    
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    			/* ignore invalid or overlong names */  | 
    
    
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    			if ((eq = strchr(e, '=')) == NULL || eq == e)  | 
    
    
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    				continue;  | 
    
    
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    			len = eq - e;  | 
    
    
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    			if (len > sizeof(name) - 1)  | 
    
    
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    				continue;  | 
    
    
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    			memcpy(name, e, len);  | 
    
    
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    			name[len] = '\0';  | 
    
    
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    			node = createnode(name, eq + 1);  | 
    
    
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    			if (RB_INSERT(envtree, &env->root, node)) { | 
    
    
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    				/* ignore any later duplicates */  | 
    
    
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    				freenode(node);  | 
    
    
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    			} else { | 
    
    
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    				env->count++;  | 
    
    
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    			}  | 
    
    
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    		}  | 
    
    
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    	}  | 
    
    
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    	return env;  | 
    
    
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    }  | 
    
    
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    static char **  | 
    
    
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    flattenenv(struct env *env)  | 
    
    
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    { | 
    
    
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    	char **envp;  | 
    
    
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    	struct envnode *node;  | 
    
    
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    	u_int i;  | 
    
    
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    	envp = reallocarray(NULL, env->count + 1, sizeof(char *));  | 
    
    
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    	if (!envp)  | 
    
    
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    		err(1, NULL);  | 
    
    
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    	i = 0;  | 
    
    
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    	RB_FOREACH(node, envtree, &env->root) { | 
    
    
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    		if (asprintf(&envp[i], "%s=%s", node->key, node->value) == -1)  | 
    
    
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    			err(1, NULL);  | 
    
    
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    		i++;  | 
    
    
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    	}  | 
    
    
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    	envp[i] = NULL;  | 
    
    
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    	return envp;  | 
    
    
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    }  | 
    
    
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    static void  | 
    
    
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    fillenv(struct env *env, const char **envlist)  | 
    
    
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    { | 
    
    
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    	struct envnode *node, key;  | 
    
    
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    	const char *e, *eq;  | 
    
    
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    	const char *val;  | 
    
    
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    	char name[1024];  | 
    
    
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    	u_int i;  | 
    
    
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    	size_t len;  | 
    
    
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    	for (i = 0; envlist[i]; i++) { | 
    
    
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    		e = envlist[i];  | 
    
    
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    		/* parse out env name */  | 
    
    
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    		if ((eq = strchr(e, '=')) == NULL)  | 
    
    
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    			len = strlen(e);  | 
    
    
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    		else  | 
    
    
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    			len = eq - e;  | 
    
    
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    		if (len > sizeof(name) - 1)  | 
    
    
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    			continue;  | 
    
    
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    		memcpy(name, e, len);  | 
    
    
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    		name[len] = '\0';  | 
    
    
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    		/* delete previous copies */  | 
    
    
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    		key.key = name;  | 
    
    
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    		if (*name == '-')  | 
    
    
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    			key.key = name + 1;  | 
    
    
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    		if ((node = RB_FIND(envtree, &env->root, &key))) { | 
    
    
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    			RB_REMOVE(envtree, &env->root, node);  | 
    
    
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    			freenode(node);  | 
    
    
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    			env->count--;  | 
    
    
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    		}  | 
    
    
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    		if (*name == '-')  | 
    
    
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    			continue;  | 
    
    
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    		/* assign value or inherit from environ */  | 
    
    
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    		if (eq) { | 
    
    
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    			val = eq + 1;  | 
    
    
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    			if (*val == '$')  | 
    
    
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    				val = getenv(val + 1);  | 
    
    
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    		} else { | 
    
    
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    			val = getenv(name);  | 
    
    
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    		}  | 
    
    
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    		/* at last, we have something to insert */  | 
    
    
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    		if (val) { | 
    
    
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    			node = createnode(name, val);  | 
    
    
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    			RB_INSERT(envtree, &env->root, node);  | 
    
    
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    			env->count++;  | 
    
    
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    		}  | 
    
    
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    	}  | 
    
    
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    }  | 
    
    
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    char **  | 
    
    
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    prepenv(const struct rule *rule)  | 
    
    
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    { | 
    
    
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    	static const char *safeset[] = { | 
    
    
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    		"DISPLAY", "HOME", "LOGNAME", "MAIL",  | 
    
    
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    		"PATH", "TERM", "USER", "USERNAME",  | 
    
    
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    		NULL  | 
    
    
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    	};  | 
    
    
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    	struct env *env;  | 
    
    
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    	env = createenv(rule);  | 
    
    
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    	/* if we started with blank, fill some defaults then apply rules */  | 
    
    
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    	if (!(rule->options & KEEPENV))  | 
    
    
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    		fillenv(env, safeset);  | 
    
    
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    	if (rule->envlist)  | 
    
    
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    		fillenv(env, rule->envlist);  | 
    
    
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    	return flattenenv(env);  | 
    
    
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    }  |