Home | History | Annotate | Line # | Download | only in mail
vars.c revision 1.3 
      1 /*
      2  * Copyright (c) 1980, 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 #ifndef lint
     35 static char sccsid[] = "from: @(#)vars.c	8.1 (Berkeley) 6/6/93";
     36 static char rcsid[] = "$Id: vars.c,v 1.3 1994/06/29 05:09:49 deraadt Exp $";
     37 #endif /* not lint */
     38 
     39 #include "rcv.h"
     40 #include "extern.h"
     41 
     42 /*
     43  * Mail -- a mail program
     44  *
     45  * Variable handling stuff.
     46  */
     47 
     48 /*
     49  * Assign a value to a variable.
     50  */
     51 void
     52 assign(name, value)
     53 	char name[], value[];
     54 {
     55 	register struct var *vp;
     56 	register int h;
     57 
     58 	h = hash(name);
     59 	vp = lookup(name);
     60 	if (vp == NOVAR) {
     61 		vp = (struct var *) calloc(sizeof *vp, 1);
     62 		vp->v_name = vcopy(name);
     63 		vp->v_link = variables[h];
     64 		variables[h] = vp;
     65 	}
     66 	else
     67 		vfree(vp->v_value);
     68 	vp->v_value = vcopy(value);
     69 }
     70 
     71 /*
     72  * Free up a variable string.  We do not bother to allocate
     73  * strings whose value is "" since they are expected to be frequent.
     74  * Thus, we cannot free same!
     75  */
     76 void
     77 vfree(cp)
     78 	char *cp;
     79 {
     80 	if (*cp)
     81 		free(cp);
     82 }
     83 
     84 /*
     85  * Copy a variable value into permanent (ie, not collected after each
     86  * command) space.  Do not bother to alloc space for ""
     87  */
     88 
     89 char *
     90 vcopy(str)
     91 	char str[];
     92 {
     93 	char *new;
     94 	unsigned len;
     95 
     96 	if (*str == '\0')
     97 		return "";
     98 	len = strlen(str) + 1;
     99 	if ((new = malloc(len)) == NULL)
    100 		panic("Out of memory");
    101 	bcopy(str, new, (int) len);
    102 	return new;
    103 }
    104 
    105 /*
    106  * Get the value of a variable and return it.
    107  * Look in the environment if its not available locally.
    108  */
    109 
    110 char *
    111 value(name)
    112 	char name[];
    113 {
    114 	register struct var *vp;
    115 
    116 	if ((vp = lookup(name)) == NOVAR)
    117 		return(getenv(name));
    118 	return(vp->v_value);
    119 }
    120 
    121 /*
    122  * Locate a variable and return its variable
    123  * node.
    124  */
    125 
    126 struct var *
    127 lookup(name)
    128 	register char name[];
    129 {
    130 	register struct var *vp;
    131 
    132 	for (vp = variables[hash(name)]; vp != NOVAR; vp = vp->v_link)
    133 		if (*vp->v_name == *name && equal(vp->v_name, name))
    134 			return(vp);
    135 	return(NOVAR);
    136 }
    137 
    138 /*
    139  * Locate a group name and return it.
    140  */
    141 
    142 struct grouphead *
    143 findgroup(name)
    144 	register char name[];
    145 {
    146 	register struct grouphead *gh;
    147 
    148 	for (gh = groups[hash(name)]; gh != NOGRP; gh = gh->g_link)
    149 		if (*gh->g_name == *name && equal(gh->g_name, name))
    150 			return(gh);
    151 	return(NOGRP);
    152 }
    153 
    154 /*
    155  * Print a group out on stdout
    156  */
    157 void
    158 printgroup(name)
    159 	char name[];
    160 {
    161 	register struct grouphead *gh;
    162 	register struct group *gp;
    163 
    164 	if ((gh = findgroup(name)) == NOGRP) {
    165 		printf("\"%s\": not a group\n", name);
    166 		return;
    167 	}
    168 	printf("%s\t", gh->g_name);
    169 	for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link)
    170 		printf(" %s", gp->ge_name);
    171 	putchar('\n');
    172 }
    173 
    174 /*
    175  * Hash the passed string and return an index into
    176  * the variable or group hash table.
    177  */
    178 int
    179 hash(name)
    180 	register char *name;
    181 {
    182 	register h = 0;
    183 
    184 	while (*name) {
    185 		h <<= 2;
    186 		h += *name++;
    187 	}
    188 	if (h < 0 && (h = -h) < 0)
    189 		h = 0;
    190 	return (h % HSHSIZE);
    191 }
    192