Home | History | Annotate | Line # | Download | only in mail
vars.c revision 1.11 
      1 /*	$NetBSD: vars.c,v 1.11 2003/08/07 11:14:42 agc Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1980, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 #if 0
     35 static char sccsid[] = "@(#)vars.c	8.1 (Berkeley) 6/6/93";
     36 #else
     37 __RCSID("$NetBSD: vars.c,v 1.11 2003/08/07 11:14:42 agc Exp $");
     38 #endif
     39 #endif /* not lint */
     40 
     41 #include "rcv.h"
     42 #include "extern.h"
     43 
     44 /*
     45  * Mail -- a mail program
     46  *
     47  * Variable handling stuff.
     48  */
     49 
     50 /*
     51  * Assign a value to a variable.
     52  */
     53 void
     54 assign(char name[], char values[])
     55 {
     56 	struct var *vp;
     57 	int h;
     58 
     59 	h = hash(name);
     60 	vp = lookup(name);
     61 	if (vp == NULL) {
     62 		vp = (struct var *) calloc(1, sizeof *vp);
     63 		vp->v_name = vcopy(name);
     64 		vp->v_link = variables[h];
     65 		variables[h] = vp;
     66 	}
     67 	else
     68                 v_free(vp->v_value);
     69 	vp->v_value = vcopy(values);
     70 }
     71 
     72 /*
     73  * Free up a variable string.  We do not bother to allocate
     74  * strings whose value is "" since they are expected to be frequent.
     75  * Thus, we cannot free same!
     76  */
     77 void
     78 v_free(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(char str[])
     91 {
     92 	char *new;
     93 	unsigned len;
     94 
     95 	if (*str == '\0')
     96 		return "";
     97 	len = strlen(str) + 1;
     98 	if ((new = malloc(len)) == NULL)
     99 		errx(1, "Out of memory");
    100 	memmove(new, str, (int) len);
    101 	return new;
    102 }
    103 
    104 /*
    105  * Get the value of a variable and return it.
    106  * Look in the environment if its not available locally.
    107  */
    108 
    109 char *
    110 value(char name[])
    111 {
    112 	struct var *vp;
    113 
    114 	if ((vp = lookup(name)) == NULL)
    115 		return(getenv(name));
    116 	return(vp->v_value);
    117 }
    118 
    119 /*
    120  * Locate a variable and return its variable
    121  * node.
    122  */
    123 
    124 struct var *
    125 lookup(char name[])
    126 {
    127 	struct var *vp;
    128 
    129 	for (vp = variables[hash(name)]; vp != NULL; vp = vp->v_link)
    130 		if (*vp->v_name == *name && equal(vp->v_name, name))
    131 			return(vp);
    132 	return(NULL);
    133 }
    134 
    135 /*
    136  * Locate a group name and return it.
    137  */
    138 
    139 struct grouphead *
    140 findgroup(char name[])
    141 {
    142 	struct grouphead *gh;
    143 
    144 	for (gh = groups[hash(name)]; gh != NULL; gh = gh->g_link)
    145 		if (*gh->g_name == *name && equal(gh->g_name, name))
    146 			return(gh);
    147 	return(NULL);
    148 }
    149 
    150 /*
    151  * Print a group out on stdout
    152  */
    153 void
    154 printgroup(char name[])
    155 {
    156 	struct grouphead *gh;
    157 	struct group *gp;
    158 
    159 	if ((gh = findgroup(name)) == NULL) {
    160 		printf("\"%s\": not a group\n", name);
    161 		return;
    162 	}
    163 	printf("%s\t", gh->g_name);
    164 	for (gp = gh->g_list; gp != NULL; gp = gp->ge_link)
    165 		printf(" %s", gp->ge_name);
    166 	putchar('\n');
    167 }
    168 
    169 /*
    170  * Hash the passed string and return an index into
    171  * the variable or group hash table.
    172  */
    173 int
    174 hash(char *name)
    175 {
    176 	int h = 0;
    177 
    178 	while (*name) {
    179 		h <<= 2;
    180 		h += *name++;
    181 	}
    182 	if (h < 0 && (h = -h) < 0)
    183 		h = 0;
    184 	return (h % HSHSIZE);
    185 }
    186