/* * 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 #include #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; }