From: Thierry Reding <treding@xxxxxxxxxx>
Given a device tree node and a property name, the fdt_count_strings()
function counts the number of strings found in the property value.
This also adds a new error code, FDT_ERR_BADVALUE, that the function
returns when it encounters a non-NUL-terminated string list.
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
Changes in v2:
- return FDT_ERR_BADVALUE error code for non-NUL-terminated properties
- add tests to cover non-NUL-terminated properties
libfdt/fdt_ro.c | 25 ++++++++++++++++
libfdt/libfdt.h | 19 +++++++++++-
tests/.gitignore | 1 +
tests/Makefile.tests | 1 +
tests/run_tests.sh | 3 ++
tests/strings.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++
tests/strings.dts | 12 ++++++++
7 files changed, 142 insertions(+), 1 deletion(-)
create mode 100644 tests/strings.c
create mode 100644 tests/strings.dts
diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c
index a65e4b5b72b6..cf55c71df79c 100644
--- a/libfdt/fdt_ro.c
+++ b/libfdt/fdt_ro.c
@@ -538,6 +538,31 @@ int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
return 0;
}
+int fdt_count_strings(const void *fdt, int nodeoffset, const char *property)
+{
+ const char *list, *end;
+ int length, count = 0;
+
+ list = fdt_getprop(fdt, nodeoffset, property, &length);
+ if (!list)
+ return -length;
+
+ end = list + length;
+
+ while (list < end) {
+ length = strnlen(list, end - list) + 1;
+
+ /* Abort if the last string isn't properly NUL-terminated. */
+ if (list + length > end)
+ return -FDT_ERR_BADVALUE;
+
+ list += length;
+ count++;
+ }
+
+ return count;
+}
+
int fdt_node_check_compatible(const void *fdt, int nodeoffset,
const char *compatible)
{
diff --git a/libfdt/libfdt.h b/libfdt/libfdt.h
index 1054512814bc..bf60c1593e4e 100644
--- a/libfdt/libfdt.h
+++ b/libfdt/libfdt.h
@@ -121,7 +121,12 @@
/* FDT_ERR_BADNCELLS: Device tree has a #address-cells, #size-cells
* or similar property with a bad format or value */
-#define FDT_ERR_MAX 14
+#define FDT_ERR_BADVALUE 15
+ /* FDT_ERR_BADVALUE: Device tree has a property with an unexpected
+ * value. For example: a property expected to contain a string list
+ * is not NUL-terminated within the length of its value. */
+
+#define FDT_ERR_MAX 15
/**********************************************************************/
/* Low-level functions (you probably don't need these) */
@@ -868,6 +873,18 @@ int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
*/
int fdt_stringlist_contains(const char *strlist, int listlen, const char *str);
+/**
+ * fdt_count_strings - count the number of strings in a string list
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of a tree node
+ * @property: name of the property containing the string list
+ * @return:
+ * the number of strings in the given property
+ * -FDT_ERR_BADVALUE if the property value is not NUL-terminated
+ * -FDT_ERR_NOTFOUND if the property does not exist
+ */
+int fdt_count_strings(const void *fdt, int nodeoffset, const char *property);
+
/**********************************************************************/
/* Read-only functions (addressing related) */
/**********************************************************************/
diff --git a/tests/.gitignore b/tests/.gitignore
index 5656555f9cbc..09a1d3b84f6f 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -49,6 +49,7 @@ tmp.*
/setprop_inplace
/sized_cells
/string_escapes
+/strings
/subnode_iterate
/subnode_offset
/supernode_atdepth_offset
diff --git a/tests/Makefile.tests b/tests/Makefile.tests
index 9adedecdff3d..415e4d670f2c 100644
--- a/tests/Makefile.tests
+++ b/tests/Makefile.tests
@@ -9,6 +9,7 @@ LIB_TESTS_L = get_mem_rsv \
sized_cells \
notfound \
addr_size_cells \
+ strings \
setprop_inplace nop_property nop_node \
sw_tree1 \
move_and_save mangle-layout nopulate \
diff --git a/tests/run_tests.sh b/tests/run_tests.sh
index 5268293434af..92ee96340c29 100755
--- a/tests/run_tests.sh
+++ b/tests/run_tests.sh
@@ -198,6 +198,9 @@ libfdt_tests () {
run_dtc_test -I dts -O dtb -o addresses.test.dtb addresses.dts
run_test addr_size_cells addresses.test.dtb
+ run_dtc_test -I dts -O dtb -o strings.test.dtb strings.dts
+ run_test strings strings.test.dtb
+
# Sequential write tests
run_test sw_tree1
tree1_tests sw_tree1.test.dtb
diff --git a/tests/strings.c b/tests/strings.c
new file mode 100644
index 000000000000..e10d9ece5a3e
--- /dev/null
+++ b/tests/strings.c
@@ -0,0 +1,82 @@
+/*
+ * libfdt - Flat Device Tree manipulation
+ * Testcase for string handling
+ * Copyright (C) 2015 NVIDIA Corporation
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+#include <libfdt.h>
+
+#include "tests.h"
+#include "testdata.h"
+
+static void check_expected_failure(const void *fdt, const char *path,
+ const char *property)
+{
+ int offset, err;
+
+ offset = fdt_path_offset(fdt, "/");
+ if (offset < 0)
+ FAIL("Couldn't find path %s", path);
+
+ err = fdt_count_strings(fdt, offset, "#address-cells");
+ if (err != -FDT_ERR_BADVALUE)
+ FAIL("unexpectedly succeeded in parsing #address-cells\n");
+}
+
+static void check_string_count(const void *fdt, const char *path,
+ const char *property, int count)
+{
+ int offset, err;
+
+ offset = fdt_path_offset(fdt, path);
+ if (offset < 0)
+ FAIL("Couldn't find path %s", path);
+
+ err = fdt_count_strings(fdt, offset, property);
+ if (err < 0)
+ FAIL("Couldn't count strings in property %s of node %s: %d\n",
+ property, path, err);
+
+ if (err != count)
+ FAIL("String count for property %s of node %s is %d instead of %d\n",
+ path, property, err, count);
+}
+
+int main(int argc, char *argv[])
+{
+ void *fdt;
+
+ if (argc != 2)
+ CONFIG("Usage: %s <dtb file>\n", argv[0]);
+
+ test_init(argc, argv);
+ fdt = load_blob(argv[1]);
+
+ check_expected_failure(fdt, "/", "#address-cells");
+ check_expected_failure(fdt, "/", "#size-cells");
+
+ check_string_count(fdt, "/", "compatible", 1);
+ check_string_count(fdt, "/device", "compatible", 2);
+ check_string_count(fdt, "/device", "big-endian", 0);
+
+ PASS();
+}
diff --git a/tests/strings.dts b/tests/strings.dts
new file mode 100644
index 000000000000..1e4d3140458f
--- /dev/null
+++ b/tests/strings.dts
@@ -0,0 +1,12 @@
+/dts-v1/;
+
+/ {
+ compatible = "test-strings";
+ #address-cells = <2>;
+ #size-cells = <2>;
+
+ device {
+ compatible = "foo", "bar";
+ big-endian;
+ };
+};
--
2.4.5
--
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