| /* |
| * libfdt - Flat Device Tree manipulation |
| * 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 |
| */ |
| #include "libfdt_env.h" |
| |
| #include <fdt.h> |
| #include <libfdt.h> |
| |
| #include "libfdt_internal.h" |
| |
| void *fdt_offset_ptr(const struct fdt_header *fdt, int offset, int len) |
| { |
| void *p; |
| |
| p = (void *)fdt + fdt32_to_cpu(fdt->off_dt_struct) + offset; |
| |
| if (p + len < p) |
| return NULL; |
| return p; |
| } |
| |
| char *fdt_string(const struct fdt_header *fdt, int stroffset) |
| { |
| return (char *)fdt + fdt32_to_cpu(fdt->off_dt_strings) + stroffset; |
| } |
| |
| int fdt_string_cmp(const struct fdt_header *fdt, int stroffset, const char *s2) |
| { |
| const char *s1 = fdt_string(fdt, stroffset); |
| int len = strlen(s2) + 1; |
| |
| if (! s1) |
| return 0; |
| |
| if ((stroffset + len < stroffset) |
| || (stroffset + len > fdt32_to_cpu(fdt->size_dt_strings))) |
| return -2; |
| |
| return strcmp(s1, s2); |
| } |
| |
| uint32_t _fdt_next_tag(const struct fdt_header *fdt, int offset, int *nextoffset) |
| { |
| const uint32_t *tagp, *lenp; |
| uint32_t tag; |
| const char *p; |
| |
| if (offset % FDT_TAGSIZE) |
| return -1; |
| |
| tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE); |
| if (! tagp) |
| return FDT_END; /* premature end */ |
| tag = fdt32_to_cpu(*tagp); |
| offset += FDT_TAGSIZE; |
| |
| switch (tag) { |
| case FDT_BEGIN_NODE: |
| /* skip name */ |
| do { |
| p = fdt_offset_ptr(fdt, offset++, 1); |
| } while (p && (*p != '\0')); |
| if (! p) |
| return FDT_END; |
| break; |
| case FDT_PROP: |
| lenp = fdt_offset_ptr(fdt, offset + FDT_TAGSIZE, sizeof(*lenp)); |
| if (! lenp) |
| return FDT_END; |
| /* skip name offset, length and value */ |
| offset += 2*FDT_TAGSIZE + fdt32_to_cpu(*lenp); |
| break; |
| } |
| |
| if (nextoffset) |
| *nextoffset = ALIGN(offset, FDT_TAGSIZE); |
| |
| return tag; |
| } |