[unix-history] / usr / src / usr.bin / mail / vars.c

#ifndef lint
static char sccsid[] = "@(#)vars.c	2.5 (Berkeley) %G%";
#endif

#include "rcv.h"

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

/*
 * Assign a value to a variable.
 */

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!
 */

vfree(cp)
	register char *cp;
{
	if (!equal(cp, ""))
		cfree(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[];
{
	register char *top, *cp, *cp2;

	if (equal(str, ""))
		return("");
	if ((top = calloc(strlen(str)+1, 1)) == NULL)
		panic ("Out of memory");
	cp = top;
	cp2 = str;
	while (*cp++ = *cp2++)
		;
	return(top);
}

/*
 * 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)
	char name[];
{
	register struct var *vp;
	register int h;

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

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

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

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

/*
 * Print a group out on stdout
 */

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);
	printf("\n");
}

/*
 * Hash the passed string and return an index into
 * the variable or group hash table.
 */

hash(name)
	char name[];
{
	register unsigned h;
	register char *cp;

	for (cp = name, h = 0; *cp; h = (h << 2) + *cp++)
		;
	if (h < 0)
		h = -h;
	if (h < 0)
		h = 0;
	return(h % HSHSIZE);
}
Commit	Line	Data
2ae9f53f SL	1	#ifndef lint
	2	static char sccsid[] = "@(#)vars.c 2.5 (Berkeley) %G%";
	3	#endif
2e4ee99d KS	4
	5	#include "rcv.h"
	6
	7	/*
	8	* Mail -- a mail program
	9	*
	10	* Variable handling stuff.
	11	*/
	12
2e4ee99d KS	13	/*
	14	* Assign a value to a variable.
	15	*/
	16
	17	assign(name, value)
	18	char name[], value[];
	19	{
	20	register struct var *vp;
	21	register int h;
	22
	23	h = hash(name);
	24	vp = lookup(name);
	25	if (vp == NOVAR) {
	26	vp = (struct var ) calloc(sizeof vp, 1);
	27	vp->v_name = vcopy(name);
	28	vp->v_link = variables[h];
	29	variables[h] = vp;
	30	}
	31	else
	32	vfree(vp->v_value);
	33	vp->v_value = vcopy(value);
	34	}
	35
	36	/*
	37	* Free up a variable string. We do not bother to allocate
	38	* strings whose value is "" since they are expected to be frequent.
	39	* Thus, we cannot free same!
	40	*/
	41
	42	vfree(cp)
	43	register char *cp;
	44	{
	45	if (!equal(cp, ""))
	46	cfree(cp);
	47	}
	48
	49	/*
	50	* Copy a variable value into permanent (ie, not collected after each
	51	* command) space. Do not bother to alloc space for ""
	52	*/
	53
	54	char *
	55	vcopy(str)
	56	char str[];
	57	{
	58	register char top, cp, *cp2;
	59
	60	if (equal(str, ""))
	61	return("");
733d2f97 CS	62	if ((top = calloc(strlen(str)+1, 1)) == NULL)
733d2f97 CS	63	panic ("Out of memory");
2e4ee99d KS	64	cp = top;
	65	cp2 = str;
	66	while (cp++ = cp2++)
	67	;
	68	return(top);
	69	}
	70
	71	/*
	72	* Get the value of a variable and return it.
	73	* Look in the environment if its not available locally.
	74	*/
	75
	76	char *
	77	value(name)
	78	char name[];
	79	{
	80	register struct var *vp;
	81
	82	if ((vp = lookup(name)) == NOVAR)
	83	return(getenv(name));
	84	return(vp->v_value);
	85	}
	86
	87	/*
	88	* Locate a variable and return its variable
	89	* node.
	90	*/
	91
	92	struct var *
	93	lookup(name)
	94	char name[];
	95	{
	96	register struct var *vp;
	97	register int h;
	98
	99	h = hash(name);
	100	for (vp = variables[h]; vp != NOVAR; vp = vp->v_link)
	101	if (equal(vp->v_name, name))
	102	return(vp);
	103	return(NOVAR);
	104	}
	105
	106	/*
	107	* Locate a group name and return it.
	108	*/
	109
	110	struct grouphead *
	111	findgroup(name)
	112	char name[];
	113	{
	114	register struct grouphead *gh;
	115	register int h;
	116
	117	h = hash(name);
	118	for (gh = groups[h]; gh != NOGRP; gh = gh->g_link)
	119	if (equal(gh->g_name, name))
	120	return(gh);
	121	return(NOGRP);
	122	}
	123
	124	/*
	125	* Print a group out on stdout
	126	*/
	127
128	printgroup(name)
129	char name[];
130	{
131	register struct grouphead *gh;
132	register struct group *gp;
133
134	if ((gh = findgroup(name)) == NOGRP) {
135	printf("\"%s\": not a group\n", name);
136	return;
137	}
138	printf("%s\t", gh->g_name);
139	for (gp = gh->g_list; gp != NOGE; gp = gp->ge_link)
140	printf(" %s", gp->ge_name);
141	printf("\n");
142	}
143
144	/*
145	* Hash the passed string and return an index into
146	* the variable or group hash table.
147	*/
148
149	hash(name)
150	char name[];
151	{
ca8907b2	152	register unsigned h;
2e4ee99d KS	153	register char *cp;
	154
	155	for (cp = name, h = 0; cp; h = (h << 2) + cp++)
	156	;
46691008 KS	157	if (h < 0)
	158	h = -h;
	159	if (h < 0)
	160	h = 0;
2e4ee99d KS	161	return(h % HSHSIZE);
2e4ee99d KS	162	}