main.c

MIPS处理器的bootloader,龙芯就是用的修改过的PMON2

void
removeselect(name)
        const char *name;
{
	register const char *n;
	register char *p, c;
	char low[500];

	/* make lowercase, then remove from select table */
	for (n = name, p = low; (c = *n) != '\0'; n++)
		*p++ = isupper(c) ? tolower(c) : c;
	*p = 0;
	n = intern(low);
	(void)ht_remove(selecttab, n);
}

/*
 * Add a "make" option.
 */
void
addmkoption(name, value)
	const char *name, *value;
{

	(void)do_option(mkopttab, &nextmkopt, name, value, "mkoptions");
}

/*
 * Add a name=value pair to an option list.  The value may be NULL.
 */
static int
do_option(ht, nppp, name, value, type)
	struct hashtab *ht;
	struct nvlist ***nppp;
	const char *name, *value, *type;
{
	register struct nvlist *nv;

	/* assume it will work */
	nv = newnv(name, value, NULL, 0, NULL);
	if (ht_insert(ht, name, nv) == 0) {
		**nppp = nv;
		*nppp = &nv->nv_next;
		return (0);
	}

	/* oops, already got that option */
	nvfree(nv);
	if ((nv = ht_lookup(ht, name)) == NULL)
		panic("do_option");
	if (nv->nv_str != NULL)
		error("already have %s `%s=%s'", type, name, nv->nv_str);
	else
		error("already have %s `%s'", type, name);
	return (1);
}

/*
 * Return true if there is at least one instance of the given unit
 * on the given device attachment (or any units, if unit == WILD).
 */
int
deva_has_instances(deva, unit)
	register struct deva *deva;
	int unit;
{
	register struct devi *i;

	if (unit == WILD)
		return (deva->d_ihead != NULL);
	for (i = deva->d_ihead; i != NULL; i = i->i_asame)
		if (unit == i->i_unit)
			return (1);
	return (0);
}

/*
 * Return true if there is at least one instance of the given unit
 * on the given base (or any units, if unit == WILD).
 */
int
devbase_has_instances(dev, unit)
	register struct devbase *dev;
	int unit;
{
	register struct deva *da;

	for (da = dev->d_ahead; da != NULL; da = da->d_bsame)
		if (deva_has_instances(da, unit))
			return (1);
	return (0);
}

static int
hasparent(i)
	register struct devi *i;
{
	register struct nvlist *nv;
	int atunit = i->i_atunit;

	/*
	 * We determine whether or not a device has a parent in in one
	 * of two ways:
	 *	(1) If a parent device was named in the config file,
	 *	    i.e. cases (2) and (3) in sem.c:adddev(), then
	 *	    we search its devbase for a matching unit number.
	 *	(2) If the device was attach to an attribute, then we
	 *	    search all attributes the device can be attached to
	 *	    for parents (with appropriate unit numebrs) that
	 *	    may be able to attach the device.
	 */

	/*
	 * Case (1): A parent was named.  Either it's configured, or not.
	 */
	if (i->i_atdev != NULL)
		return (devbase_has_instances(i->i_atdev, atunit));

	/*
	 * Case (2): No parent was named.  Look for devs that provide the attr.
	 */
	if (i->i_atattr != NULL)
		for (nv = i->i_atattr->a_refs; nv != NULL; nv = nv->nv_next)
			if (devbase_has_instances(nv->nv_ptr, atunit))
				return (1);
	return (0);
}

static int
cfcrosscheck(cf, what, nv)
	register struct config *cf;
	const char *what;
	register struct nvlist *nv;
{
	register struct devbase *dev;
	register struct devi *pd;
	int errs, devminor;

	for (errs = 0; nv != NULL; nv = nv->nv_next) {
		if (nv->nv_name == NULL)
			continue;
		dev = ht_lookup(devbasetab, nv->nv_name);
		if (dev == NULL)
			panic("cfcrosscheck(%s)", nv->nv_name);
		devminor = minor(nv->nv_int) / 16;
		if (devbase_has_instances(dev, devminor))
			continue;
		if (devbase_has_instances(dev, STAR) &&
		    devminor >= dev->d_umax)
			continue;
		for (pd = allpseudo; pd != NULL; pd = pd->i_next)
			if (pd->i_base == dev && devminor < dev->d_umax &&
			    devminor >= 0)
				goto loop;
		(void)fprintf(stderr,
		    "%s:%d: %s says %s on %s, but there's no %s\n",
		    conffile, cf->cf_lineno,
		    cf->cf_name, what, nv->nv_str, nv->nv_str);
		errs++;
loop:
	}
	return (errs);
}

/*
 * Cross-check the configuration: make sure that each target device
 * or attribute (`at foo[0*?]') names at least one real device.  Also
 * see that the root, swap, and dump devices for all configurations
 * are there.
 */
int
crosscheck()
{
	register struct devi *i;
	register struct config *cf;
	int errs;

	errs = 0;
	for (i = alldevi; i != NULL; i = i->i_next) {
		if (i->i_at == NULL || hasparent(i))
			continue;
		xerror(conffile, i->i_lineno,
		    "%s at %s is orphaned", i->i_name, i->i_at);
		(void)fprintf(stderr, " (%s %s declared)\n",
		    i->i_atunit == WILD ? "nothing matching" : "no",
		    i->i_at);
		errs++;
	}
	if (allcf == NULL) {
		(void)fprintf(stderr, "%s has no configurations!\n",
		    conffile);
		errs++;
	}
	for (cf = allcf; cf != NULL; cf = cf->cf_next) {
		if (cf->cf_root != NULL) {	/* i.e., not swap generic */
			errs += cfcrosscheck(cf, "root", cf->cf_root);
			errs += cfcrosscheck(cf, "swap", cf->cf_swap);
			errs += cfcrosscheck(cf, "dumps", cf->cf_dump);
		}
	}
	return (errs);
}

/*
 * Check to see if there is a *'d unit with a needs-count file.
 */
int
badstar()
{
	register struct devbase *d;
	register struct deva *da;
	register struct devi *i;
	register int errs, n;

	errs = 0;
	for (d = allbases; d != NULL; d = d->d_next) {
		for (da = d->d_ahead; da != NULL; da = da->d_bsame)
			for (i = da->d_ihead; i != NULL; i = i->i_asame) {
				if (i->i_unit == STAR)
					goto foundstar;
			}
		continue;
	foundstar:
		if (ht_lookup(needcnttab, d->d_name)) {
			(void)fprintf(stderr,
		    "config: %s's cannot be *'d until its driver is fixed\n",
			    d->d_name);
			errs++;
			continue;
		}
		for (n = 0; i != NULL; i = i->i_alias)
			if (!i->i_collapsed)
				n++;
		if (n < 1)
			panic("badstar() n<1");
	}
	return (errs);
}

/*
 * Verify/create builddir if necessary, change to it, and verify srcdir.
 * This will be called when we see the first include.
 */
void
setupdirs()
{
	struct stat st;

	/* srcdir must be specified if builddir is not specified or if
	 * no configuration filename was specified. */
	if ((builddir || strcmp(defbuilddir, ".") == 0) && !srcdir) {
		error("source directory must be specified");
		exit(1);
	}

	if (srcdir == NULL)
		srcdir = "../../../..";
	if (builddir == NULL)
		builddir = defbuilddir;

	if (stat(builddir, &st) != 0) {
		if (mkdir(builddir, 0777)) {
			(void)fprintf(stderr, "config: cannot create %s: %s\n",
			    builddir, strerror(errno));
			exit(2);
		}
		madedir = 1;
	} else if (!S_ISDIR(st.st_mode)) {
		(void)fprintf(stderr, "config: %s is not a directory\n",
			      builddir);
		exit(2);
	}
	if (chdir(builddir) != 0) {
		(void)fprintf(stderr, "config: cannot change to %s\n",
			      builddir);
		exit(2);
	}
	if (stat(srcdir, &st) != 0 || !S_ISDIR(st.st_mode)) {
		(void)fprintf(stderr, "config: %s is not a directory\n",
			      srcdir);
		exit(2);
	}
}

struct opt {
	const char *name;
	const char *val;
};

int
optcmp(sp1, sp2)
	struct opt *sp1, *sp2;
{
	int r;

	r = strcmp(sp1->name, sp2->name);
	if (r == 0) {
		if (!sp1->val && !sp2->val)
			r = 0;	
		else if (sp1->val && !sp2->val)
			r = -1;
		else if (sp2->val && !sp1->val)
			r = 1;
		else r = strcmp(sp1->val, sp2->val);
	}
	return (r);
}

void
optiondelta()
{
	register struct nvlist *nv;
	char nbuf[BUFSIZ], obuf[BUFSIZ];	/* XXX size */
	int nnewopts, ret = 0, i;
	struct opt *newopts;
	FILE *fp;

	for (nnewopts = 0, nv = options; nv != NULL; nv = nv->nv_next)
		nnewopts++;
	newopts = (struct opt *)malloc(nnewopts * sizeof(struct opt));
	if (newopts == NULL)
		ret = 0;
	for (i = 0, nv = options; nv != NULL; nv = nv->nv_next, i++) {
		newopts[i].name = nv->nv_name;
		newopts[i].val = nv->nv_str;
	}
	qsort(newopts, nnewopts, sizeof (struct opt), optcmp);

	/* compare options against previous config */
	if ((fp = fopen("options", "r"))) {
		for (i = 0; !feof(fp) && i < nnewopts && ret == 0; i++) {
			if (newopts[i].val)
				snprintf(nbuf, sizeof nbuf, "%s=%s\n",
				    newopts[i].name, newopts[i].val);
			else
				snprintf(nbuf, sizeof nbuf, "%s\n",
				    newopts[i].name);
			if (fgets(obuf, sizeof obuf, fp) == NULL ||
			    strcmp(nbuf, obuf))
				ret = 1;
		}
		fclose(fp);
		fp = NULL;
	} else
		ret = 1;

	/* replace with the new list of options */
	if ((fp = fopen("options", "w+"))) {
		rewind(fp);
		for (i = 0; i < nnewopts; i++) {
			if (newopts[i].val)
				fprintf(fp, "%s=%s\n", newopts[i].name,
				    newopts[i].val);
			else
				fprintf(fp, "%s\n", newopts[i].name);
		}
		fclose(fp);
	}
	free(newopts);
	if (ret == 0 || madedir == 1)
		return;
	(void)printf("Kernel options have changed -- you must run \"make clean\"\n");
}