libfdt: Abolish fdt_property_offset()

fdt_property_offset() is the only function in the library returning a
direct offset to a property, and no function takes such an offset
(they only take offsets to nodes, not properties).  Furthermore the
only client uses for this function I can think of involve immediately
translating the offset into a pointer, effectively duplicating the
internal function _fdt_getprop()

This function abolishes fdt_property_offset(), replacing it with
fdt_get_property(), a renamed and now externally visible version of
_fdt_getprop().

fdt_ro.c

@@ -30,6 +30,13 @@
 			return OFFSET_ERROR(err); \
 	}
 
+#define PTR_CHECK_HEADER(fdt) \
+	{ \
+		int err; \
+		if ((err = _fdt_check_header(fdt)) != 0) \
+			return PTR_ERROR(err); \
+	}
+
 static int offset_streq(const struct fdt_header *fdt, int offset,
 			const char *s, int len)
 {
@@ -53,66 +60,6 @@ char *fdt_string(const struct fdt_header *fdt, int stroffset)
 	return (char *)fdt + fdt_off_dt_strings(fdt) + stroffset;
 }
 
-int fdt_property_offset(const struct fdt_header *fdt, int nodeoffset,
-			const char *name)
-{
-	int level = 0;
-	uint32_t tag;
-	struct fdt_property *prop;
-	int namestroff;
-	int offset, nextoffset;
-
-	OFFSET_CHECK_HEADER(fdt);
-
-	if (nodeoffset % FDT_TAGSIZE)
-		return OFFSET_ERROR(FDT_ERR_BADOFFSET);
-
-	tag = _fdt_next_tag(fdt, nodeoffset, &nextoffset);
-	if (tag != FDT_BEGIN_NODE)
-		return OFFSET_ERROR(FDT_ERR_BADOFFSET);
-
-	do {
-		offset = nextoffset;
-		if (offset % FDT_TAGSIZE)
-			return OFFSET_ERROR(FDT_ERR_INTERNAL);
-
-		tag = _fdt_next_tag(fdt, offset, &nextoffset);
-		switch (tag) {
-		case FDT_END:
-			return OFFSET_ERROR(FDT_ERR_TRUNCATED);
-
-		case FDT_BEGIN_NODE:
-			level++;
-			break;
-
-		case FDT_END_NODE:
-			level--;
-			break;
-
-		case FDT_PROP:
-			if (level != 0)
-				continue;
-
-			prop = fdt_offset_ptr_typed(fdt, offset, prop);
-			if (! prop)
-				return OFFSET_ERROR(FDT_ERR_BADSTRUCTURE);
-			namestroff = fdt32_to_cpu(prop->nameoff);
-			if (streq(fdt_string(fdt, namestroff), name))
-				/* Found it! */
-				return offset;
-			break;
-
-		case FDT_NOP:
-			break;
-
-		default:
-			return OFFSET_ERROR(FDT_ERR_BADSTRUCTURE);
-		}
-	} while (level >= 0);
-
-	return OFFSET_ERROR(FDT_ERR_NOTFOUND);
-}
-
 int fdt_subnode_offset_namelen(const struct fdt_header *fdt, int parentoffset,
 			       const char *name, int namelen)
 {
@@ -197,30 +144,75 @@ int fdt_path_offset(const struct fdt_header *fdt, const char *path)
 	return offset;	
 }
 
-struct fdt_property *_fdt_getprop(const struct fdt_header *fdt, int nodeoffset,
-				  const char *name, int *lenp)
+struct fdt_property *fdt_get_property(const struct fdt_header *fdt,
+				      int nodeoffset,
+				      const char *name, int *lenp)
 {
-	int propoffset;
+	int level = 0;
+	uint32_t tag;
 	struct fdt_property *prop;
-	int err;
-	int len;
+	int namestroff;
+	int offset, nextoffset;
 
-	propoffset = fdt_property_offset(fdt, nodeoffset, name);
-	if ((err = fdt_offset_error(propoffset)))
-		return PTR_ERROR(err);
+	PTR_CHECK_HEADER(fdt);
+
+	if (nodeoffset % FDT_TAGSIZE)
+		return PTR_ERROR(FDT_ERR_BADOFFSET);
+
+	tag = _fdt_next_tag(fdt, nodeoffset, &nextoffset);
+	if (tag != FDT_BEGIN_NODE)
+		return PTR_ERROR(FDT_ERR_BADOFFSET);
+
+	do {
+		offset = nextoffset;
+		if (offset % FDT_TAGSIZE)
+			return PTR_ERROR(FDT_ERR_INTERNAL);
+
+		tag = _fdt_next_tag(fdt, offset, &nextoffset);
+		switch (tag) {
+		case FDT_END:
+			return PTR_ERROR(FDT_ERR_TRUNCATED);
+
+		case FDT_BEGIN_NODE:
+			level++;
+			break;
+
+		case FDT_END_NODE:
+			level--;
+			break;
+
+		case FDT_PROP:
+			if (level != 0)
+				continue;
 
-	prop = fdt_offset_ptr(fdt, propoffset, sizeof(prop));
-	if (! prop)
-		return PTR_ERROR(FDT_ERR_BADSTRUCTURE);
-	len = fdt32_to_cpu(prop->len);
-	prop = fdt_offset_ptr(fdt, propoffset, sizeof(prop) + len);
-	if (! prop)
-		return PTR_ERROR(FDT_ERR_BADSTRUCTURE);
+			prop = fdt_offset_ptr_typed(fdt, offset, prop);
+			if (! prop)
+				return PTR_ERROR(FDT_ERR_BADSTRUCTURE);
+			namestroff = fdt32_to_cpu(prop->nameoff);
+			if (streq(fdt_string(fdt, namestroff), name)) {
+				/* Found it! */
+				int len = fdt32_to_cpu(prop->len);
+				prop = fdt_offset_ptr(fdt, offset,
+						      sizeof(prop)+len);
+				if (! prop)
+					return PTR_ERROR(FDT_ERR_BADSTRUCTURE);
+
+				if (lenp)
+					*lenp = len;
+				
+				return prop;
+			}
+			break;
 
-	if (lenp)
-		*lenp = len;
+		case FDT_NOP:
+			break;
+
+		default:
+			return PTR_ERROR(FDT_ERR_BADSTRUCTURE);
+		}
+	} while (level >= 0);
 
-	return prop;
+	return PTR_ERROR(FDT_ERR_NOTFOUND);
 }
 
 void *fdt_getprop(const struct fdt_header *fdt, int nodeoffset,
@@ -229,7 +221,7 @@ void *fdt_getprop(const struct fdt_header *fdt, int nodeoffset,
 	const struct fdt_property *prop;
 	int err;
 
-	prop = _fdt_getprop(fdt, nodeoffset, name, lenp);
+	prop = fdt_get_property(fdt, nodeoffset, name, lenp);
 	if ((err = fdt_ptr_error(prop)))
 		return PTR_ERROR(err);
 

fdt_rw.c

@@ -126,7 +126,7 @@ static struct fdt_property *_resize_property(struct fdt_header *fdt, int nodeoff
 	int oldlen;
 	int err;
 
-	prop = _fdt_getprop(fdt, nodeoffset, name, &oldlen);
+	prop = fdt_get_property(fdt, nodeoffset, name, &oldlen);
 	if ((err = fdt_ptr_error(prop)))
 		return PTR_ERROR(err);
 
@@ -203,7 +203,7 @@ int fdt_delprop(struct fdt_header *fdt, int nodeoffset, const char *name)
 
 	RW_OFFSET_CHECK_HEADER(fdt);
 
-	prop = _fdt_getprop(fdt, nodeoffset, name, &len);
+	prop = fdt_get_property(fdt, nodeoffset, name, &len);
 	if ((err = fdt_ptr_error(prop)))
 		return err;
 

fdt_wip.c

@@ -55,7 +55,7 @@ int fdt_nop_property(struct fdt_header *fdt, int nodeoffset, const char *name)
 	int len;
 	int err;
 
-	prop = _fdt_getprop(fdt, nodeoffset, name, &len);
+	prop = fdt_get_property(fdt, nodeoffset, name, &len);
 	if ((err = fdt_ptr_error(prop)))
 		return err;
 

libfdt.h

@@ -72,8 +72,6 @@ struct fdt_header *fdt_move(const struct fdt_header *fdt, void *buf, int bufsize
 /* Read-only functions */
 char *fdt_string(const struct fdt_header *fdt, int stroffset);
 
-int fdt_property_offset(const struct fdt_header *fdt, int nodeoffset,
-			const char *name);
 int fdt_subnode_offset_namelen(const struct fdt_header *fdt, int parentoffset,
 			       const char *name, int namelen);
 int fdt_subnode_offset(const struct fdt_header *fdt, int parentoffset,
@@ -81,6 +79,9 @@ int fdt_subnode_offset(const struct fdt_header *fdt, int parentoffset,
 
 int fdt_path_offset(const struct fdt_header *fdt, const char *path);
 
+struct fdt_property *fdt_get_property(const struct fdt_header *fdt,
+				      int nodeoffset,
+				      const char *name, int *lenp);
 void *fdt_getprop(const struct fdt_header *fdt, int nodeoffset,
 		  const char *name, int *lenp);
 

libfdt_internal.h

@@ -35,8 +35,6 @@ static inline int _ptr_offset(struct fdt_header *fdt, void *p)
 
 int _fdt_check_header(const struct fdt_header *fdt);
 uint32_t _fdt_next_tag(const struct fdt_header *fdt, int startoffset, int *nextoffset);
-struct fdt_property *_fdt_getprop(const struct fdt_header *fdt, int nodeoffset,
-				  const char *name, int *lenp);
 const char *_fdt_find_string(const char *strtab, int tabsize, const char *s);
 int _fdt_node_end_offset(struct fdt_header *fdt, int nodeoffset);
 

tests/Makefile

@@ -1,6 +1,6 @@
 PREFIX = /usr/local
 
-LIB_TESTS = root_node property_offset subnode_offset path_offset getprop \
+LIB_TESTS = root_node find_property subnode_offset path_offset getprop \
 	notfound \
 	setprop_inplace nop_property nop_node \
 	sw_tree1 \

tests/notfound.c

@@ -36,6 +36,7 @@ void check_error(const char *s, int err)
 
 int main(int argc, char *argv[])
 {
+	struct fdt_property *prop;
 	struct fdt_header *fdt;
 	int offset;
 	int subnode1_offset;
@@ -45,9 +46,9 @@ int main(int argc, char *argv[])
 	test_init(argc, argv);
 	fdt = load_blob_arg(argc, argv);
 
-	offset = fdt_property_offset(fdt, 0, "nonexistant-property");
-	check_error("fdt_property_offset(\"nonexistant-property\")",
-		    fdt_offset_error(offset));
+	prop = fdt_get_property(fdt, 0, "nonexistant-property", NULL);
+	check_error("fdt_get_property(\"nonexistant-property\")",
+		    fdt_ptr_error(prop));
 
 	val = fdt_getprop(fdt, 0, "nonexistant-property", NULL);
 	check_error("fdt_getprop(\"nonexistant-property\"",

tests/run_tests.sh

@@ -14,7 +14,7 @@ tree1_tests () {
 
     # Read-only tests
     run_test root_node $TREE
-    run_test property_offset $TREE
+    run_test find_property $TREE
     run_test subnode_offset $TREE
     run_test path_offset $TREE
     run_test getprop $TREE

tests/testutils.c

@@ -106,20 +106,12 @@ const char *fdt_strerror(int errval)
 void check_property(struct fdt_header *fdt, int nodeoffset, const char *name,
 		    int len, const void *val)
 {
-	int offset;
 	const struct fdt_property *prop;
 	uint32_t tag, nameoff, proplen;
 	const char *propname;
-	int err;
 
 	verbose_printf("Checking property \"%s\"...", name);
-	offset = fdt_property_offset(fdt, nodeoffset, name);
-	verbose_printf("offset %d...", offset);
-	if ((err = fdt_offset_error(offset)))
-		FAIL("fdt_property_offset(\"%s\"): %s", name,
-		     fdt_strerror(err));
-
-	prop = fdt_offset_ptr_typed(fdt, offset, prop);
+	prop = fdt_get_property(fdt, nodeoffset, name, NULL);
 	verbose_printf("pointer %p\n", prop);
 	if (! prop)
 		FAIL("NULL retreiving \"%s\" pointer", name);