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Diffstat (limited to 'libfdt/fdt.c')
-rw-r--r-- | libfdt/fdt.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/libfdt/fdt.c b/libfdt/fdt.c new file mode 100644 index 0000000..772da46 --- /dev/null +++ b/libfdt/fdt.c @@ -0,0 +1,124 @@ +/* + * 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" + +int _fdt_check_header(const void *fdt) +{ + if (fdt_magic(fdt) == FDT_MAGIC) { + /* Complete tree */ + if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION) + return -FDT_ERR_BADVERSION; + if (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION) + return -FDT_ERR_BADVERSION; + } else if (fdt_magic(fdt) == SW_MAGIC) { + /* Unfinished sequential-write blob */ + if (fdt_size_dt_struct(fdt) == 0) + return -FDT_ERR_BADSTATE; + } else { + return -FDT_ERR_BADMAGIC; + } + + return 0; +} + +void *fdt_offset_ptr(const void *fdt, int offset, int len) +{ + void *p; + + if (fdt_version(fdt) >= 0x11) + if (((offset + len) < offset) + || ((offset + len) > fdt_size_dt_struct(fdt))) + return NULL; + + p = _fdt_offset_ptr(fdt, offset); + + if (p + len < p) + return NULL; + return p; +} + +uint32_t _fdt_next_tag(const void *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, 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; +} + +const char *_fdt_find_string(const char *strtab, int tabsize, const char *s) +{ + int len = strlen(s) + 1; + const char *last = strtab + tabsize - len; + const char *p; + + for (p = strtab; p <= last; p++) + if (memeq(p, s, len)) + return p; + return NULL; +} + +int fdt_move(const void *fdt, void *buf, int bufsize) +{ + int err = _fdt_check_header(fdt); + + if (err) + return err; + + if (fdt_totalsize(fdt) > bufsize) + return -FDT_ERR_NOSPACE; + + memmove(buf, fdt, fdt_totalsize(fdt)); + return 0; +} |