mirror of
https://github.com/JakeHillion/drgn.git
synced 2024-12-23 09:43:06 +00:00
111 lines
2.9 KiB
C
111 lines
2.9 KiB
C
// Copyright (c) Facebook, Inc. and its affiliates.
|
|
// SPDX-License-Identifier: GPL-3.0-or-later
|
|
|
|
/**
|
|
* @file
|
|
*
|
|
* Paths.
|
|
*
|
|
* See @ref Paths.
|
|
*/
|
|
|
|
#ifndef DRGN_PATH_H
|
|
#define DRGN_PATH_H
|
|
|
|
#include <stdbool.h>
|
|
#include <stddef.h>
|
|
|
|
#include <elfutils/libdw.h>
|
|
|
|
#include "util.h"
|
|
|
|
/**
|
|
* @ingroup Internals
|
|
*
|
|
* @defgroup Paths Paths
|
|
*
|
|
* Utilities for working with paths.
|
|
*
|
|
* @{
|
|
*/
|
|
|
|
/**
|
|
* Path component iterator.
|
|
*
|
|
* This iterates over the components of a file path, joining multiple components
|
|
* and normalizing the result. Normalization:
|
|
*
|
|
* - Collapses redundant "/" separators.
|
|
* - Removes "." components.
|
|
* - Removes ".." components when possible.
|
|
*
|
|
* Components are emitted in @b reverse. So, "a/b/c" is emitted in the order
|
|
* "c", "b", "a" (this allows the implementation to operate in O(n) time and
|
|
* O(1) space).
|
|
*
|
|
* Absolute paths have an implicit empty component, so "/a/b" is emitted as "b",
|
|
* "a", "".
|
|
*
|
|
* Relative paths are emitted relative to a hypothetical current directory. A
|
|
* path referring to the current directory (e.g., "." or "a/..") does not emit
|
|
* any components.
|
|
*
|
|
* ".." components above the current directory are included, so "a/b/../../../c"
|
|
* is emitted as "c", "..". However, ".." components above an absolute path are
|
|
* not meaningful, so "/a/b/../../../c" is emitted as "c", "".
|
|
*
|
|
* A empty path does not emit any components.
|
|
*/
|
|
struct path_iterator {
|
|
/**
|
|
* Array of input components.
|
|
*
|
|
* The input components are treated as if they were joined with a "/".
|
|
* @ref string::str and @ref string::len should be initialized for each
|
|
* component. The latter will be modified as the path is iterated.
|
|
*/
|
|
struct string *components;
|
|
/** Number of components in @ref path_iterator::components. */
|
|
size_t num_components;
|
|
/**
|
|
* Current number of ".." components.
|
|
*
|
|
* Initialize this to 0.
|
|
*/
|
|
size_t dot_dot;
|
|
};
|
|
|
|
/**
|
|
* Get the next component from a @ref path_iterator.
|
|
*
|
|
* Components are emitted in reverse. This will never emit a "." component. It
|
|
* will emit an empty ("") component only for an absolute path. It may emit ".."
|
|
* components if there are any that go above the current directory.
|
|
*
|
|
* @param[in] it Iterator.
|
|
* @param[out] component_ret Returned component.
|
|
* @param[out] component_len_ret Length of @c component.
|
|
* @return @c true if we returned a componenent, @c false if there were no more
|
|
* components.
|
|
*/
|
|
bool path_iterator_next(struct path_iterator *it, const char **component_ret,
|
|
size_t *component_len_ret);
|
|
|
|
/**
|
|
* Return whether the path @p haystack ends with the path @p needle once both
|
|
* are normalized.
|
|
*
|
|
* The unit of comparison is a path component, not a character. Thus, "ab/cd/ef"
|
|
* ends with "cd/ef", but not "d/ef".
|
|
*
|
|
* @sa path_iterator
|
|
*/
|
|
bool path_ends_with(struct path_iterator *haystack,
|
|
struct path_iterator *needle);
|
|
|
|
bool die_matches_filename(Dwarf_Die *die, const char *filename);
|
|
|
|
/** @} */
|
|
|
|
#endif /* DRGN_PATH_H */
|