Hints overhaul:

- Replace some very poorly thought out API hacks that should have been
  fixed a long while ago.
- Provide some much more flexible search functions (resource_find_*())
- Use strings for storage instead of an outgrowth of the rather
  inconvenient temporary ioconf table from config().  We already had a
  fallback to using strings before malloc/vm was running anyway.

1 files changed, 304 insertions, 0 deletions

diff --git a/sys/kern/subr_hints.c b/sys/kern/subr_hints.c
new file mode 100644
index 0000000..a201fa0
--- /dev/null
+++ b/sys/kern/subr_hints.c
@@ -0,0 +1,304 @@
+/*-
+ * Copyright (c) 2000,2001 Peter Wemm <peter@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/bus.h>
+
+/*
+ * Access functions for device resources.
+ */
+
+extern char static_hints[];		/* by config for now */
+
+/*
+ * Evil wildcarding resource string lookup.
+ * This walks the supplied env string table and returns a match.
+ * The start point can be remembered for incremental searches.
+ */
+static int
+res_find(const char *cp, int *line, int *startln,
+    const char *name, int *unit, const char *resname, const char *value,
+    const char **ret_name, int *ret_namelen, int *ret_unit,
+    const char **ret_resname, int *ret_resnamelen, const char **ret_value)
+{
+	int n = 0, hit;
+	char r_name[32];
+	int r_unit;
+	char r_resname[32];
+	char r_value[128];
+	const char *s;
+	char *p;
+
+	while (cp) {
+		hit = 1;
+		(*line)++;
+		if (strncmp(cp, "hint.", 5) != 0)
+			hit = 0;
+		else
+			n = sscanf(cp, "hint.%32[^.].%d.%32[^=]=%128s",
+			    r_name, &r_unit, r_resname, r_value);
+		if (hit && n != 4) {
+			printf("CONFIG: invalid hint '%s'\n", cp);
+			/* XXX: abuse bogus index() declaration */
+			p = index(cp, 'h');
+			*p = 'H';
+			hit = 0;
+		}
+		if (hit && startln && *startln >= 0 && *line < *startln)
+			hit = 0;
+		if (hit && name && strcmp(name, r_name) != 0)
+			hit = 0;
+		if (hit && unit && *unit != r_unit)
+			hit = 0;
+		if (hit && resname && strcmp(resname, r_resname) != 0)
+			hit = 0;
+		if (hit && value && strcmp(value, r_value) != 0)
+			hit = 0;
+		if (hit)
+			break;
+		while (*cp != '\0')
+			cp++;
+		cp++;
+		if (*cp == '\0') {
+			cp = NULL;
+			break;
+		}
+	}
+	if (cp == NULL)
+		return ENOENT;
+
+	s = cp;
+	/* This is a bit of a hack, but at least is reentrant */
+	/* Note that it returns some !unterminated! strings. */
+	s = index(s, '.') + 1;		/* start of device */
+	if (ret_name)
+		*ret_name = s;
+	s = index(s, '.') + 1;		/* start of unit */
+	if (ret_namelen)
+		*ret_namelen = s - *ret_name - 1; /* device length */
+	if (ret_unit)
+		*ret_unit = r_unit;
+	s = index(s, '.') + 1;		/* start of resname */
+	if (ret_resname)
+		*ret_resname = s;
+	s = index(s, '=') + 1;		/* start of value */
+	if (ret_resnamelen)
+		*ret_resnamelen = s - *ret_resname - 1; /* value len */
+	if (ret_value)
+		*ret_value = s;
+	if (startln)			/* line number for anchor */
+		*startln = *line + 1;
+	return 0;
+}
+
+/*
+ * Search all the data sources for matches to our query.  We look for
+ * dynamic hints first as overrides for static or fallback hints.
+ */
+static int
+resource_find(int *line, int *startln,
+    const char *name, int *unit, const char *resname, const char *value,
+    const char **ret_name, int *ret_namelen, int *ret_unit,
+    const char **ret_resname, int *ret_resnamelen, const char **ret_value)
+{
+	int i;
+	int un;
+
+	*line = 0;
+
+	/* Search for exact unit matches first */
+	i = res_find(kern_envp, line, startln, name, unit, resname, value,
+	    ret_name, ret_namelen, ret_unit, ret_resname, ret_resnamelen,
+	    ret_value);
+	if (i == 0)
+		return 0;
+	i = res_find(static_hints, line, startln, name, unit, resname, value,
+	    ret_name, ret_namelen, ret_unit, ret_resname, ret_resnamelen,
+	    ret_value);
+	if (i == 0)
+		return 0;
+	if (unit == NULL)
+		return ENOENT;
+	/* If we are still here, search for wildcard matches */
+	un = -1;
+	i = res_find(kern_envp, line, startln, name, &un, resname, value,
+	    ret_name, ret_namelen, ret_unit, ret_resname, ret_resnamelen,
+	    ret_value);
+	if (i == 0)
+		return 0;
+	un = -1;
+	i = res_find(static_hints, line, startln, name, &un, resname, value,
+	    ret_name, ret_namelen, ret_unit, ret_resname, ret_resnamelen,
+	    ret_value);
+	if (i == 0)
+		return 0;
+	return ENOENT;
+}
+
+int
+resource_int_value(const char *name, int unit, const char *resname, int *result)
+{
+	int error;
+	const char *str;
+	char *op;
+	unsigned long val;
+	int line;
+
+	line = 0;
+	error = resource_find(&line, NULL, name, &unit, resname, NULL,
+	    NULL, NULL, NULL, NULL, NULL, &str);
+	if (error)
+		return error;
+	if (*str == '\0') 
+		return EFTYPE;
+	val = strtoul(str, &op, 0);
+	if (*op != '\0') 
+		return EFTYPE;
+	*result = val;
+	return 0;
+}
+
+int
+resource_long_value(const char *name, int unit, const char *resname,
+    long *result)
+{
+	int error;
+	const char *str;
+	char *op;
+	unsigned long val;
+	int line;
+
+	line = 0;
+	error = resource_find(&line, NULL, name, &unit, resname, NULL,
+	    NULL, NULL, NULL, NULL, NULL, &str);
+	if (error)
+		return error;
+	if (*str == '\0') 
+		return EFTYPE;
+	val = strtoul(str, &op, 0);
+	if (*op != '\0') 
+		return EFTYPE;
+	*result = val;
+	return 0;
+}
+
+int
+resource_string_value(const char *name, int unit, const char *resname,
+    const char **result)
+{
+	int error;
+	const char *str;
+	int line;
+
+	line = 0;
+	error = resource_find(&line, NULL, name, &unit, resname, NULL,
+	    NULL, NULL, NULL, NULL, NULL, &str);
+	if (error)
+		return error;
+	*result = str;
+	return 0;
+}
+
+/*
+ * This is a bit nasty, but allows us to not modify the env strings.
+ */
+static const char *
+resource_string_copy(const char *s, int len)
+{
+	static char stringbuf[256];
+	static int offset = 0;
+	const char *ret;
+
+	if (len == 0)
+		len = strlen(s);
+	if (len > 255)
+		return NULL;
+	if ((offset + len + 1) > 255)
+		offset = 0;
+	bcopy(s, &stringbuf[offset], len);
+	stringbuf[offset + len] = '\0';
+	ret = &stringbuf[offset];
+	offset += len + 1;
+	return ret;
+}
+
+/*
+ * err = resource_find_at(&anchor, &name, &unit, resname, value)
+ * Iteratively fetch a list of devices wired "at" something
+ * res and value are restrictions.  eg: "at", "scbus0".
+ * For practical purposes, res = required, value = optional.
+ * *name and *unit are set.
+ * set *anchor to zero before starting.
+ */
+int
+resource_find_match(int *anchor, const char **name, int *unit,
+    const char *resname, const char *value)
+{
+	const char *found_name;
+	int found_namelen;
+	int found_unit;
+	int ret;
+	int newln;
+
+	newln = *anchor;
+	ret = resource_find(anchor, &newln, NULL, NULL, resname, value,
+	    &found_name, &found_namelen, &found_unit, NULL, NULL, NULL);
+	if (ret == 0) {
+		*name = resource_string_copy(found_name, found_namelen);
+		*unit = found_unit;
+	}
+	*anchor = newln;
+	return ret;
+}
+
+
+/*
+ * err = resource_find_dev(&anchor, name, &unit, res, value);
+ * Iterate through a list of devices, returning their unit numbers.
+ * res and value are optional restrictions.  eg: "at", "scbus0".
+ * *unit is set to the value.
+ * set *anchor to zero before starting.
+ */
+int
+resource_find_dev(int *anchor, const char *name, int *unit,
+    const char *resname, const char *value)
+{
+	int found_unit;
+	int newln;
+	int ret;
+
+	newln = *anchor;
+	ret = resource_find(anchor, &newln, name, NULL, resname, value,
+	    NULL, NULL, &found_unit, NULL, NULL, NULL);
+	if (ret == 0) {
+		*unit = found_unit;
+	}
+	*anchor = newln;
+	return ret;
+}