159 lines
7.0 KiB
C
159 lines
7.0 KiB
C
/* read and write binary file "partitions" described by FMAP */
|
|
/*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; version 2 of the License.
|
|
*
|
|
* This program 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 General Public License for more details.
|
|
*/
|
|
|
|
#ifndef PARITITONED_FILE_H_
|
|
#define PARITITONED_FILE_H_
|
|
|
|
#include "common.h"
|
|
#include "flashmap/fmap.h"
|
|
|
|
#include <stdbool.h>
|
|
#include <stddef.h>
|
|
|
|
typedef struct partitioned_file partitioned_file_t;
|
|
|
|
/**
|
|
* Create a new filesystem-backed flat buffer.
|
|
* This backwards-compatibility function creates a new in-memory buffer and
|
|
* backing binary file of the specified size. Although the file won't actually
|
|
* have multiple regions, it'll still be possible to access and manipulate it
|
|
* using this module; this is accomplished by requesting the special region
|
|
* whose name matches SECTION_NAME_PRIMARY_CBFS, which maps to the whole file.
|
|
* Note that the caller will be responsible for calling partitioned_file_close()
|
|
* on the returned object, and that this function will overwrite any existing
|
|
* file with the given name without warning.
|
|
*
|
|
* @param filename Name of the backing file
|
|
* @param image_size Size of the image
|
|
* @return Caller-owned partitioned file, or NULL on error
|
|
*/
|
|
partitioned_file_t *partitioned_file_create_flat(const char *filename,
|
|
size_t image_size);
|
|
|
|
/**
|
|
* Create a new filesystem-backed partitioned buffer.
|
|
* This creates a new in-memory buffer and backing binary file. Both are
|
|
* segmented into regions according to the provided flashmap's sections, and the
|
|
* flashmap itself is automatically copied into the region named
|
|
* SECTION_NAME_FMAP: a section with this name must already exist in the FMAP.
|
|
* After calling this function, it is safe for the caller to clean up flashmap
|
|
* at any time. The partitioned_file_t returned from this function is separately
|
|
* owned by the caller, and must later be passed to partitioned_file_close().
|
|
* Note that this function will overwrite any existing file with the given name
|
|
* without warning.
|
|
*
|
|
* @param filename Name of the backing file
|
|
* @param flashmap Buffer containing an FMAP file layout
|
|
* @return Caller-owned partitioned file, or NULL on error
|
|
*/
|
|
partitioned_file_t *partitioned_file_create(const char *filename,
|
|
struct buffer *flashmap);
|
|
|
|
/**
|
|
* Read a file back in from the disk.
|
|
* An in-memory buffer is created and populated with the file's
|
|
* contents. If the image contains an FMAP, it will be opened as a
|
|
* full partitioned file; otherwise, it will be opened as a flat file as
|
|
* if it had been created by partitioned_file_create_flat().
|
|
* The partitioned_file_t returned from this function is separately owned by the
|
|
* caller, and must later be passed to partitioned_file_close();
|
|
*
|
|
* @param filename Name of the file to read in
|
|
* @param write_access True if the file needs to be modified
|
|
* @return Caller-owned partitioned file, or NULL on error
|
|
*/
|
|
partitioned_file_t *partitioned_file_reopen(const char *filename,
|
|
bool write_access);
|
|
|
|
/**
|
|
* Write a buffer's contents to its original region within a segmented file.
|
|
* This function should only be called on buffers originally retrieved by a call
|
|
* to partitioned_file_read_region() on the same partitioned file object. The
|
|
* contents of this buffer are copied back to the same region of the buffer and
|
|
* backing file that the region occupied before.
|
|
*
|
|
* @param file Partitioned file to which to write the data
|
|
* @param buffer Modified buffer obtained from partitioned_file_read_region()
|
|
* @return Whether the operation was successful
|
|
*/
|
|
bool partitioned_file_write_region(partitioned_file_t *file,
|
|
const struct buffer *buffer);
|
|
|
|
/**
|
|
* Obtain one particular region of a segmented file.
|
|
* The result is owned by the partitioned_file_t and shared among every caller
|
|
* of this function. Thus, it is an error to buffer_delete() it; instead, clean
|
|
* up the entire partitioned_file_t once it's no longer needed with a single
|
|
* call to partitioned_file_close().
|
|
* Note that, if the buffer obtained from this function is modified, the changes
|
|
* will be reflected in any buffers handed out---whether earlier or later---for
|
|
* any region inclusive of the altered location(s). However, the backing file
|
|
* will not be updated until someone calls partitioned_file_write_region() on a
|
|
* buffer that includes the alterations.
|
|
*
|
|
* @param dest Empty destination buffer for the data
|
|
* @param file Partitioned file from which to read the data
|
|
* @param region Name of the desired FMAP region
|
|
* @return Whether the copy was performed successfully
|
|
*/
|
|
bool partitioned_file_read_region(struct buffer *dest,
|
|
const partitioned_file_t *file, const char *region);
|
|
|
|
/** @param file Partitioned file to flush and cleanup */
|
|
void partitioned_file_close(partitioned_file_t *file);
|
|
|
|
/** @return Whether the file is partitioned (i.e. not flat). */
|
|
bool partitioned_file_is_partitioned(const partitioned_file_t *file);
|
|
|
|
/** @return The image's overall filesize, regardless of whether it's flat. */
|
|
size_t partitioned_file_total_size(const partitioned_file_t *file);
|
|
|
|
/** @return Whether the specified region begins with the magic bytes. */
|
|
bool partitioned_file_region_check_magic(const partitioned_file_t *file,
|
|
const char *region, const char *magic, size_t magic_len);
|
|
|
|
/** @return Whether the specified region exists and contains nested regions. */
|
|
bool partitioned_file_region_contains_nested(const partitioned_file_t *file,
|
|
const char *region);
|
|
|
|
/** @return An immutable reference to the FMAP, or NULL for flat images. */
|
|
const struct fmap *partitioned_file_get_fmap(const partitioned_file_t *file);
|
|
|
|
/** @return Whether to include area in the running count. */
|
|
typedef bool (*partitioned_file_fmap_selector_t)
|
|
(const struct fmap_area *area, const void *arg);
|
|
|
|
/**
|
|
* Count the number of FMAP entries fulfilling a certain criterion.
|
|
* The result is always 0 if run on a flat (non-partitioned) image.
|
|
*
|
|
* @param file File on whose FMAP entries the operation should be run
|
|
* @param callback Decider answering whether each individual region should count
|
|
* @param arg Additional information to furnish to the decider on each call
|
|
* @return The number of FMAP sections with that property
|
|
*/
|
|
unsigned partitioned_file_fmap_count(const partitioned_file_t *file,
|
|
partitioned_file_fmap_selector_t callback, const void *arg);
|
|
|
|
/** Selector that counts every single FMAP section. */
|
|
extern const partitioned_file_fmap_selector_t partitioned_file_fmap_select_all;
|
|
|
|
/** Selector that counts FMAP sections that are descendants of fmap_area arg. */
|
|
extern const partitioned_file_fmap_selector_t
|
|
partitioned_file_fmap_select_children_of;
|
|
|
|
/** Selector that counts FMAP sections that contain the fmap_area arg. */
|
|
extern const partitioned_file_fmap_selector_t
|
|
partitioned_file_fmap_select_parents_of;
|
|
|
|
#endif
|