drgn/libdrgn/memory_reader.h
Omar Sandoval de6a4e07ae libdrgn: fix Doxygen
The Doxygen documentation for libdrgn has bit-rotted over time. Bring
back the Internal module, clean up a few renamed members and parameters,
and fix broken parsing caused by the generic definition macros.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
2020-09-30 01:32:33 -07:00

135 lines
3.5 KiB
C

// Copyright (c) Facebook, Inc. and its affiliates.
// SPDX-License-Identifier: GPL-3.0+
/**
* @file
*
* Memory reading interface.
*
* See @ref MemoryReader.
*/
#ifndef DRGN_MEMORY_READER_H
#define DRGN_MEMORY_READER_H
#include "binary_search_tree.h"
#include "drgn.h"
/**
* @ingroup Internals
*
* @defgroup MemoryReader Memory reader
*
* Memory reading interface.
*
* @ref drgn_memory_reader provides a common interface for registering regions
* of memory in a program and reading from memory.
*
* @{
*/
/** Memory segment in a @ref drgn_memory_reader. */
struct drgn_memory_segment {
struct binary_tree_node node;
/** Address of the segment in memory. */
uint64_t address;
/** Size of the segment in bytes; */
uint64_t size;
/**
* The address of the segment when it was added, before any truncations.
*
* This is always greater than or equal to @ref
* drgn_memory_segment::address.
*/
uint64_t orig_address;
/** Read callback. */
drgn_memory_read_fn read_fn;
/** Argument to pass to @ref drgn_memory_segment::read_fn. */
void *arg;
};
static inline uint64_t
drgn_memory_segment_to_key(const struct drgn_memory_segment *entry)
{
return entry->address;
}
DEFINE_BINARY_SEARCH_TREE_TYPE(drgn_memory_segment_tree,
struct drgn_memory_segment,
node, drgn_memory_segment_to_key)
/**
* Memory reader.
*
* A memory reader maps the segments of memory in an address space to callbacks
* which can be used to read memory from those segments.
*/
struct drgn_memory_reader {
/** Virtual memory segments. */
struct drgn_memory_segment_tree virtual_segments;
/** Physical memory segments. */
struct drgn_memory_segment_tree physical_segments;
};
/**
* Initialize a @ref drgn_memory_reader.
*
* The reader is initialized with no segments.
*/
void drgn_memory_reader_init(struct drgn_memory_reader *reader);
/** Deinitialize a @ref drgn_memory_reader. */
void drgn_memory_reader_deinit(struct drgn_memory_reader *reader);
/** Return whether a @ref drgn_memory_reader has no segments. */
bool drgn_memory_reader_empty(struct drgn_memory_reader *reader);
/** @sa drgn_program_add_memory_segment() */
struct drgn_error *
drgn_memory_reader_add_segment(struct drgn_memory_reader *reader,
uint64_t address, uint64_t size,
drgn_memory_read_fn read_fn, void *arg,
bool physical);
/**
* Read from a @ref drgn_memory_reader.
*
* @param[in] reader Memory reader.
* @param[out] buf Buffer to read into.
* @param[in] address Starting address in memory to read.
* @param[in] count Number of bytes to read.
* @param[in] physical Whether @c address is physical.
* @return @c NULL on success, non-@c NULL on error.
*/
struct drgn_error *drgn_memory_reader_read(struct drgn_memory_reader *reader,
void *buf, uint64_t address,
size_t count, bool physical);
/** Argument for @ref drgn_read_memory_file(). */
struct drgn_memory_file_segment {
/** Offset in the file where the segment starts. */
uint64_t file_offset;
/**
* Size of the segment in the file. This may be less than the size of
* the segment in memory, in which case the remaining bytes are treated
* as if they contained zeroes.
*/
uint64_t file_size;
/** File descriptor. */
int fd;
/**
* If @c true, EIO is treated as a fault. Otherwise, it is treated as an
* OS error.
*/
bool eio_is_fault;
};
/** @ref drgn_memory_read_fn which reads from a file. */
struct drgn_error *drgn_read_memory_file(void *buf, uint64_t address,
size_t count, uint64_t offset,
void *arg, bool physical);
/** @} */
#endif /* DRGN_MEMORY_READER_H */