usr/src/usr.bin/mail/vars.c

/*
 * Copyright (c) 1980, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * %sccs.include.redist.c%
 */

#ifndef lint
static char sccsid[] = "@(#)vars.c	8.1 (Berkeley) %G%";
#endif /* not lint */

#include "rcv.h"
#include "extern.h"

/*
 * Mail -- a mail program
 *
 * Variable handling stuff.
 */

/*
 * Assign a value to a variable.
 */
void
assign(name, value)
	char name[], value[];
{
	register struct var *vp;
	register int h;

	h = hash(name);
	vp = lookup(name);
	if (vp == NOVAR) {
		vp = (struct var *) calloc(sizeof *vp, 1);
		vp->v_name = vcopy(name);
		vp->v_link = variables[h];
		variables[h] = vp;
	}
	else
		vfree(vp->v_value);
	vp->v_value = vcopy(value);
}

/*
 * Free up a variable string.  We do not bother to allocate
 * strings whose value is "" since they are expected to be frequent.
 * Thus, we cannot free same!
 */
void
vfree(cp)
	char *cp;
{
	if (*cp)
		free(cp);
}

/*
 * Copy a variable value into permanent (ie, not collected after each
 * command) space.  Do not bother to alloc space for ""
 */

char *
vcopy(str)
	char str[];
{
	char *new;
	unsigned len;

	if (*str == '\0')
		return "";
	len = strlen(str) + 1;
	if ((new = malloc(len)) == NULL)
		panic("Out of memory");
	bcopy(str, new, (int) len);
	return new;
}

/*
 * Get the value of a variable and return it.
 * Look in the environment if its not available locally.
 */

char *
value(name)
	char name[];
{
	register struct var *vp;

	if ((vp = lookup(name)) == NOVAR)
		return(getenv(name));
	return(vp->v_value);
}

/*
 * Locate a variable and return its variable
 * node.
 */

struct var *
lookup(name)
	register char name[];
{
	register struct var *vp;

	for (vp = variables[hash(name)]; vp != NOVAR; vp = vp->v_link)
		if (*vp->v_name == *name && equal(vp->v_name, name))
			return(vp);
	return(NOVAR);
}

/*
 * Locate a group name and return it.
 */

struct grouphead *
findgroup(name)
	register char name[];
{
	register struct grouphead *gh;

	for (gh = groups[hash(name)]; gh != NOGRP; gh = gh->g_link)
		if (*gh->g_name == *name && equal(gh->g_name, name))
			return(gh);
	return(NOGRP);
}

/*
 * Print a group out on stdout
 */
void
printgroup(name)
	char name[];
{
	register struct grouphead *gh;
	register struct group *gp;

	if ((gh = findgroup(name)) == NOGRP) {
		printf("\"%s\": not a group\n", name);
		return;
	}
	printf("%s\t", gh->g_name);
	for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link)
		printf(" %s", gp->ge_name);
	putchar('\n');
}

/*
 * Hash the passed string and return an index into
 * the variable or group hash table.
 */
int
hash(name)
	register char *name;
{
	register h = 0;

	while (*name) {
		h <<= 2;
		h += *name++;
	}
	if (h < 0 && (h = -h) < 0)
		h = 0;
	return (h % HSHSIZE);
}
Commit	Line	Data
	1	/*
	2	* Copyright (c) 1980, 1993
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* %sccs.include.redist.c%
	6	*/
	7
	8	#ifndef lint
	9	static char sccsid[] = "@(#)vars.c 8.1 (Berkeley) %G%";
	10	#endif /* not lint */
	11
	12	#include "rcv.h"
	13	#include "extern.h"
	14
	15	/*
	16	* Mail -- a mail program
	17	*
	18	* Variable handling stuff.
	19	*/
	20
	21	/*
	22	* Assign a value to a variable.
	23	*/
	24	void
	25	assign(name, value)
	26	char name[], value[];
	27	{
	28	register struct var *vp;
	29	register int h;
	30
	31	h = hash(name);
	32	vp = lookup(name);
	33	if (vp == NOVAR) {
	34	vp = (struct var ) calloc(sizeof vp, 1);
	35	vp->v_name = vcopy(name);
	36	vp->v_link = variables[h];
	37	variables[h] = vp;
	38	}
	39	else
	40	vfree(vp->v_value);
	41	vp->v_value = vcopy(value);
	42	}
	43
	44	/*
	45	* Free up a variable string. We do not bother to allocate
	46	* strings whose value is "" since they are expected to be frequent.
	47	* Thus, we cannot free same!
	48	*/
	49	void
	50	vfree(cp)
	51	char *cp;
	52	{
	53	if (*cp)
	54	free(cp);
	55	}
	56
	57	/*
	58	* Copy a variable value into permanent (ie, not collected after each
	59	* command) space. Do not bother to alloc space for ""
	60	*/
	61
	62	char *
	63	vcopy(str)
	64	char str[];
	65	{
	66	char *new;
	67	unsigned len;
	68
	69	if (*str == '\0')
	70	return "";
	71	len = strlen(str) + 1;
	72	if ((new = malloc(len)) == NULL)
	73	panic("Out of memory");
	74	bcopy(str, new, (int) len);
	75	return new;
	76	}
	77
	78	/*
	79	* Get the value of a variable and return it.
	80	* Look in the environment if its not available locally.
	81	*/
	82
	83	char *
	84	value(name)
	85	char name[];
	86	{
	87	register struct var *vp;
	88
	89	if ((vp = lookup(name)) == NOVAR)
	90	return(getenv(name));
	91	return(vp->v_value);
	92	}
	93
	94	/*
	95	* Locate a variable and return its variable
	96	* node.
	97	*/
	98
	99	struct var *
	100	lookup(name)
	101	register char name[];
	102	{
	103	register struct var *vp;
	104
	105	for (vp = variables[hash(name)]; vp != NOVAR; vp = vp->v_link)
	106	if (vp->v_name == name && equal(vp->v_name, name))
	107	return(vp);
	108	return(NOVAR);
	109	}
	110
	111	/*
	112	* Locate a group name and return it.
	113	*/
	114
	115	struct grouphead *
	116	findgroup(name)
	117	register char name[];
	118	{
	119	register struct grouphead *gh;
	120
	121	for (gh = groups[hash(name)]; gh != NOGRP; gh = gh->g_link)
	122	if (gh->g_name == name && equal(gh->g_name, name))
	123	return(gh);
	124	return(NOGRP);
	125	}
	126
	127	/*
	128	* Print a group out on stdout
	129	*/
	130	void
	131	printgroup(name)
	132	char name[];
	133	{
	134	register struct grouphead *gh;
	135	register struct group *gp;
	136
	137	if ((gh = findgroup(name)) == NOGRP) {
	138	printf("\"%s\": not a group\n", name);
	139	return;
	140	}
	141	printf("%s\t", gh->g_name);
	142	for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link)
	143	printf(" %s", gp->ge_name);
	144	putchar('\n');
	145	}
	146
	147	/*
	148	* Hash the passed string and return an index into
	149	* the variable or group hash table.
	150	*/
	151	int
	152	hash(name)
	153	register char *name;
	154	{
	155	register h = 0;
	156
	157	while (*name) {
	158	h <<= 2;
	159	h += *name++;
	160	}
	161	if (h < 0 && (h = -h) < 0)
	162	h = 0;
	163	return (h % HSHSIZE);
	164	}