From 037db263e04f43cb113064fa24e1b441ff761528 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Thu, 30 Aug 2007 14:54:04 +1000 Subject: [PATCH] libfdt: Add fdt_get_path() function This patch adds an fdt_get_path() function to libfdt, which returns the full path of a given node in a caller supplied buffer. Signed-off-by: David Gibson --- libfdt/fdt_ro.c | 66 ++++++++++++++++++++++++++++++++ libfdt/libfdt.h | 2 + tests/Makefile.tests | 2 +- tests/get_path.c | 91 ++++++++++++++++++++++++++++++++++++++++++++ tests/run_tests.sh | 1 + 5 files changed, 161 insertions(+), 1 deletion(-) create mode 100644 tests/get_path.c diff --git a/libfdt/fdt_ro.c b/libfdt/fdt_ro.c index 9ff862b..0e9deb5 100644 --- a/libfdt/fdt_ro.c +++ b/libfdt/fdt_ro.c @@ -283,3 +283,69 @@ const void *fdt_getprop(const void *fdt, int nodeoffset, return prop->data; } + +int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen) +{ + uint32_t tag; + int p = 0, overflow = 0; + int offset, nextoffset, namelen; + const char *name; + + CHECK_HEADER(fdt); + + tag = _fdt_next_tag(fdt, 0, &nextoffset); + if (tag != FDT_BEGIN_NODE) + return -FDT_ERR_BADSTRUCTURE; + + if (buflen < 2) + return -FDT_ERR_NOSPACE; + buf[0] = '/'; + p = 1; + + while (offset < nodeoffset) { + offset = nextoffset; + tag = _fdt_next_tag(fdt, offset, &nextoffset); + switch (tag) { + case FDT_END: + return -FDT_ERR_BADOFFSET; + + case FDT_BEGIN_NODE: + name = fdt_get_name(fdt, offset, &namelen); + if (!name) + return namelen; + if (overflow || ((p + namelen + 1) > buflen)) { + overflow++; + break; + } + memcpy(buf + p, name, namelen); + p += namelen; + buf[p++] = '/'; + break; + + case FDT_END_NODE: + if (overflow) { + overflow--; + break; + } + do { + p--; + } while (buf[p-1] != '/'); + break; + + case FDT_PROP: + case FDT_NOP: + break; + + default: + return -FDT_ERR_BADSTRUCTURE; + } + } + + if (overflow) + return -FDT_ERR_NOSPACE; + + if (p > 1) /* special case so that root path is "/", not "" */ + p--; + buf[p] = '\0'; + return p; +} diff --git a/libfdt/libfdt.h b/libfdt/libfdt.h index f8fd459..c72db48 100644 --- a/libfdt/libfdt.h +++ b/libfdt/libfdt.h @@ -136,6 +136,8 @@ static inline void *fdt_getprop_w(void *fdt, int nodeoffset, return (void *)fdt_getprop(fdt, nodeoffset, name, lenp); } +int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen); + /* Write-in-place functions */ int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name, const void *val, int len); diff --git a/tests/Makefile.tests b/tests/Makefile.tests index ae9b78c..34dd0a4 100644 --- a/tests/Makefile.tests +++ b/tests/Makefile.tests @@ -1,5 +1,5 @@ LIB_TESTS_L = root_node find_property subnode_offset path_offset \ - get_name getprop \ + get_name getprop get_path \ notfound \ setprop_inplace nop_property nop_node \ sw_tree1 \ diff --git a/tests/get_path.c b/tests/get_path.c new file mode 100644 index 0000000..1f09479 --- /dev/null +++ b/tests/get_path.c @@ -0,0 +1,91 @@ +/* + * libfdt - Flat Device Tree manipulation + * Testcase for fdt_get_path() + * Copyright (C) 2006 David Gibson, IBM 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 + */ +#define _GNU_SOURCE + +#include +#include +#include +#include + +#include +#include + +#include "tests.h" +#include "testdata.h" + +#define POISON ('\xff') + +void check_path_buf(void *fdt, const char *path, int pathlen, int buflen) +{ + int offset; + char buf[buflen+1]; + int len; + + offset = fdt_path_offset(fdt, path); + if (offset < 0) + FAIL("Couldn't find path \"%s\": %s", path, fdt_strerror(offset)); + + memset(buf, POISON, sizeof(buf)); /* poison the buffer */ + + len = fdt_get_path(fdt, offset, buf, buflen); + if (buflen <= pathlen) { + if (len != -FDT_ERR_NOSPACE) + FAIL("fdt_get_path([%d bytes]) returns %d with " + "insufficient buffer space", buflen, len); + } else { + if (len < 0) + FAIL("fdt_get_path([%d bytes]): %s", buflen, + fdt_strerror(len)); + if (len != pathlen) + FAIL("fdt_get_path([%d bytes]) reports length %d " + "instead of %d", buflen, len, pathlen); + if (strcmp(buf, path) != 0) + FAIL("fdt_get_path([%d bytes]) returns \"%s\" " + "instead of \"%s\"", buflen, buf, path); + } + + if (buf[buflen] != POISON) + FAIL("fdt_get_path([%d bytes]) overran buffer", buflen); +} + +void check_path(void *fdt, const char *path) +{ + int pathlen = strlen(path); + + check_path_buf(fdt, path, pathlen, 1024); + check_path_buf(fdt, path, pathlen, pathlen+1); + check_path_buf(fdt, path, pathlen, pathlen); +} + +int main(int argc, char *argv[]) +{ + void *fdt; + + test_init(argc, argv); + fdt = load_blob_arg(argc, argv); + + check_path(fdt, "/"); + check_path(fdt, "/subnode1"); + check_path(fdt, "/subnode2"); + check_path(fdt, "/subnode1/subsubnode"); + check_path(fdt, "/subnode2/subsubnode"); + + PASS(); +} diff --git a/tests/run_tests.sh b/tests/run_tests.sh index 4198f5f..d0d4bb1 100755 --- a/tests/run_tests.sh +++ b/tests/run_tests.sh @@ -34,6 +34,7 @@ tree1_tests () { run_test path_offset $TREE run_test get_name $TREE run_test getprop $TREE + run_test get_path $TREE run_test notfound $TREE # Write-in-place tests