| /* |
| * Copyright 2013, Google Inc. |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| * Alternatively, this software may be distributed under the terms of the |
| * GNU General Public License ("GPL") version 2 as published by the Free |
| * Software Foundation. |
| * |
| * This is ported from the flashmap utility: http://flashmap.googlecode.com |
| */ |
| |
| #ifndef FLASHMAP_LIB_SEARCH_H__ |
| #define FLASHMAP_LIB_SEARCH_H__ |
| |
| /* Our current state in the search process */ |
| enum search_state_t { |
| SEARCH_STATE_START, |
| SEARCH_STATE_USE_HANDLER, /* Call handler function */ |
| SEARCH_STATE_BINARY_SEARCH, /* Fast binary search */ |
| SEARCH_STATE_FULL_SEARCH, /* Slow incremental search */ |
| SEARCH_STATE_DONE, /* Search completed */ |
| }; |
| |
| /* Keeps track of the state of our search */ |
| struct search_info { |
| struct flashctx *flash; /* Flash information */ |
| enum search_state_t state; /* Current state */ |
| long int ceiling_size; /* Lowest power of 2 >= flash size */ |
| long int stride; /* Current binary search stride */ |
| off_t offset; /* Next offset to return */ |
| uint8_t *image; /* Cache of entire flash image */ |
| int min_size; /* Minimum size of data to find */ |
| /* |
| * Utility wrapper for using external programs to aid in our search. |
| * @search: Pointer to search information |
| * @offset: Wrapper will set this if successful |
| * |
| * @return 0 if successful, -1 to indicate failure or offset not |
| * found by utility |
| */ |
| int (*handler)(struct search_info *search, off_t *offset); |
| }; |
| |
| /** |
| * search_find_next() - Find the next offset to check in a search operation |
| * |
| * If search->image is not NULL, then it contains the full flash image and |
| * the caller can use this instead of reading the data again. |
| * |
| * @search: Search information, set up by search_init() |
| * @offsetp: Returns next offset to check |
| * @return 0 if we have an offset, -1 if we have run out of places to look |
| */ |
| int search_find_next(struct search_info *search, off_t *offsetp); |
| |
| /** search_init() - Get ready to start a search |
| * |
| * @search: Search information, set up by this function |
| * @flash: Information about the flash chip |
| * @min_size: Minimum size of region that we want to find |
| */ |
| void search_init(struct search_info *search, struct flashctx *flash, |
| int min_size); |
| |
| /** search_free() - Free memory allocated by search |
| * |
| * @search: Search information, set up by search_init() |
| */ |
| void search_free(struct search_info *search); |
| |
| #endif |