[babeltrace.git] / plugins / lttng-utils / bin-info.h

#ifndef _BABELTRACE_BIN_INFO_H
#define _BABELTRACE_BIN_INFO_H

/*
 * Babeltrace - Executable and Shared Object Debug Info Reader
 *
 * Copyright 2015 Antoine Busque <abusque@efficios.com>
 *
 * Author: Antoine Busque <abusque@efficios.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <stdint.h>
#include <stdbool.h>
#include <gelf.h>
#include <elfutils/libdw.h>
#include <babeltrace/babeltrace-internal.h>

#define DEFAULT_DEBUG_DIR "/usr/lib/debug"
#define DEBUG_SUBDIR ".debug/"
#define BUILD_ID_SUBDIR ".build-id/"
#define BUILD_ID_SUFFIX ".debug"

struct bin_info {
	/* Base virtual memory address. */
	uint64_t low_addr;
	/* Upper bound of exec address space. */
	uint64_t high_addr;
	/* Size of exec address space. */
	uint64_t memsz;
	/* Paths to ELF and DWARF files. */
	char *elf_path;
	char *dwarf_path;
	/* libelf and libdw objects representing the files. */
	Elf *elf_file;
	Dwarf *dwarf_info;
	/* Optional build ID info. */
	uint8_t *build_id;
	size_t build_id_len;

	/* Optional debug link info. */
	char *dbg_link_filename;
	uint32_t dbg_link_crc;
	/* FDs to ELF and DWARF files. */
	int elf_fd;
	int dwarf_fd;
	/* Configuration. */
	char *debug_info_dir;
	/* Denotes whether the executable is position independent code. */
	bool is_pic:1;
	/* denotes whether the build id in the trace matches to one on disk. */
	bool file_build_id_matches:1;
	/*
	 * Denotes whether the executable only has ELF symbols and no
	 * DWARF info.
	 */
	bool is_elf_only:1;
};

struct source_location {
	uint64_t line_no;
	char *filename;
};

/**
 * Initializes the bin_info framework. Call this before calling
 * anything else.
 *
 * @returns		0 on success, -1 on failure
 */
BT_HIDDEN
int bin_info_init(void);

/**
 * Instantiate a structure representing an ELF executable, possibly
 * with DWARF info, located at the given path.
 *
 * @param path		Path to the ELF file
 * @param low_addr	Base address of the executable
 * @param memsz	In-memory size of the executable
 * @param is_pic	Whether the executable is position independent
 *			code (PIC)
 * @param debug_info_dir Directory containing debug info or NULL.
 * @param target_prefix  Path to the root file system of the target
 *                       or NULL.
 * @returns		Pointer to the new bin_info on success,
 *			NULL on failure.
 */
BT_HIDDEN
struct bin_info *bin_info_create(const char *path, uint64_t low_addr,
		uint64_t memsz, bool is_pic, const char *debug_info_dir,
		const char *target_prefix);

/**
 * Destroy the given bin_info instance
 *
 * @param bin	bin_info instance to destroy
 */
BT_HIDDEN
void bin_info_destroy(struct bin_info *bin);

/**
 * Sets the build ID information for a given bin_info instance.
 *
 * @param bin		The bin_info instance for which to set
 *			the build ID
 * @param build_id	Array of bytes containing the actual ID
 * @param build_id_len	Length in bytes of the build_id
 * @returns		0 on success, -1 on failure
 */
BT_HIDDEN
int bin_info_set_build_id(struct bin_info *bin, uint8_t *build_id,
		size_t build_id_len);

/**
 * Sets the debug link information for a given bin_info instance.
 *
 * @param bin		The bin_info instance for which to set
 *			the debug link
 * @param filename	Name of the separate debug info file
 * @param crc		Checksum for the debug info file
 * @returns		0 on success, -1 on failure
 */
BT_HIDDEN
int bin_info_set_debug_link(struct bin_info *bin, const char *filename,
		uint32_t crc);

/**
 * Returns whether or not the given bin info \p bin contains the
 * address \p addr.
 *
 * @param bin		bin_info instance
 * @param addr		Address to lookup
 * @returns		1 if \p bin contains \p addr, 0 if it does not,
 *			-1 on failure
 */
static inline
int bin_info_has_address(struct bin_info *bin, uint64_t addr)
{
	if (!bin) {
		return -1;
	}

	return addr >= bin->low_addr && addr < bin->high_addr;
}

/**
 * Get the name of the function containing a given address within an
 * executable.
 *
 * If no DWARF info is available, the function falls back to ELF
 * symbols and the "function name" is in fact the name of the closest
 * symbol, followed by the offset between the symbol and the address.
 *
 * On success, if found, the out parameter `func_name` is set. The ownership
 * of `func_name` is passed to the caller. On failure, `func_name` remains
 * unchanged.
 *
 * @param bin		bin_info instance for the executable containing
 *			the address
 * @param addr		Virtual memory address for which to find the
 *			function name
 * @param func_name	Out parameter, the function name.
 * @returns		0 on success, -1 on failure
 */
BT_HIDDEN
int bin_info_lookup_function_name(struct bin_info *bin, uint64_t addr,
		char **func_name);

/**
 * Get the source location (file name and line number) for a given
 * address within an executable.
 *
 * If no DWARF info is available, the source location cannot be found
 * and the function will return unsuccessfully.
 *
 * On success, if found, the out parameter `src_loc` is set. The ownership
 * of `src_loc` is passed to the caller. On failure, `src_loc` remains
 * unchanged.
 *
 * @param bin		bin_info instance for the executable containing
 *			the address
 * @param addr		Virtual memory address for which to find the
 *			source location
 * @param src_loc	Out parameter, the source location
 * @returns		0 on success, -1 on failure
 */
BT_HIDDEN
int bin_info_lookup_source_location(struct bin_info *bin, uint64_t addr,
		struct source_location **src_loc);
/**
 * Get a string representing the location within the binary of a given
 * address.
 *
 * In the  case of a PIC binary, the location is relative (+0x1234).
 * For a non-PIC binary, the location is absolute (@0x1234)
 *
 * On success, the out parameter `bin_loc` is set. The ownership is
 * passed to the caller. On failure, `bin_loc` remains unchanged.
 *
 * @param bin		bin_info instance for the executable containing
 *			the address
 * @param addr		Virtual memory address for which to find the
 *			binary location
 * @param bin_loc	Out parameter, the binary location
 * @returns		0 on success, -1 on failure
 */
BT_HIDDEN
int bin_info_get_bin_loc(struct bin_info *bin, uint64_t addr, char **bin_loc);

/**
 * Destroy the given source_location instance
 *
 * @param src_loc	source_location instance to destroy
 */
BT_HIDDEN
void source_location_destroy(struct source_location *src_loc);

#endif	/* _BABELTRACE_BIN_INFO_H */
Commit	Line	Data
d5ddf820 AB	1	#ifndef _BABELTRACE_BIN_INFO_H
d5ddf820 AB	2	#define _BABELTRACE_BIN_INFO_H
c40a57e5 AB	3
	4	/*
	5	* Babeltrace - Executable and Shared Object Debug Info Reader
	6	*
	7	* Copyright 2015 Antoine Busque <abusque@efficios.com>
	8	*
	9	* Author: Antoine Busque <abusque@efficios.com>
	10	*
	11	* Permission is hereby granted, free of charge, to any person obtaining a copy
	12	* of this software and associated documentation files (the "Software"), to deal
	13	* in the Software without restriction, including without limitation the rights
	14	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	15	* copies of the Software, and to permit persons to whom the Software is
	16	* furnished to do so, subject to the following conditions:
	17	*
	18	* The above copyright notice and this permission notice shall be included in
	19	* all copies or substantial portions of the Software.
	20	*
	21	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	22	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	23	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	24	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	25	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	26	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	27	* SOFTWARE.
	28	*/
	29
	30	#include <stdint.h>
	31	#include <stdbool.h>
	32	#include <gelf.h>
	33	#include <elfutils/libdw.h>
	34	#include <babeltrace/babeltrace-internal.h>
	35
	36	#define DEFAULT_DEBUG_DIR "/usr/lib/debug"
	37	#define DEBUG_SUBDIR ".debug/"
	38	#define BUILD_ID_SUBDIR ".build-id/"
	39	#define BUILD_ID_SUFFIX ".debug"
	40
d5ddf820	41	struct bin_info {
c40a57e5 AB	42	/* Base virtual memory address. */
	43	uint64_t low_addr;
	44	/* Upper bound of exec address space. */
	45	uint64_t high_addr;
	46	/* Size of exec address space. */
	47	uint64_t memsz;
	48	/* Paths to ELF and DWARF files. */
	49	char *elf_path;
	50	char *dwarf_path;
	51	/* libelf and libdw objects representing the files. */
	52	Elf *elf_file;
	53	Dwarf *dwarf_info;
	54	/* Optional build ID info. */
	55	uint8_t *build_id;
	56	size_t build_id_len;
ca9f27f3	57
c40a57e5 AB	58	/* Optional debug link info. */
	59	char *dbg_link_filename;
	60	uint32_t dbg_link_crc;
	61	/* FDs to ELF and DWARF files. */
	62	int elf_fd;
	63	int dwarf_fd;
9d325e17 PP	64	/* Configuration. */
9d325e17 PP	65	char *debug_info_dir;
c40a57e5 AB	66	/* Denotes whether the executable is position independent code. */
c40a57e5 AB	67	bool is_pic:1;
ca9f27f3 FD	68	/* denotes whether the build id in the trace matches to one on disk. */
ca9f27f3 FD	69	bool file_build_id_matches:1;
d5ddf820 AB	70	/*
	71	* Denotes whether the executable only has ELF symbols and no
	72	* DWARF info.
	73	*/
c40a57e5 AB	74	bool is_elf_only:1;
	75	};
	76
	77	struct source_location {
	78	uint64_t line_no;
	79	char *filename;
	80	};
	81
	82	/**
d5ddf820	83	* Initializes the bin_info framework. Call this before calling
c40a57e5 AB	84	* anything else.
	85	*
	86	* @returns 0 on success, -1 on failure
	87	*/
	88	BT_HIDDEN
d5ddf820	89	int bin_info_init(void);
c40a57e5 AB	90
	91	/**
	92	* Instantiate a structure representing an ELF executable, possibly
	93	* with DWARF info, located at the given path.
	94	*
	95	* @param path Path to the ELF file
	96	* @param low_addr Base address of the executable
	97	* @param memsz In-memory size of the executable
9f2b13ca AB	98	* @param is_pic Whether the executable is position independent
9f2b13ca AB	99	* code (PIC)
9d325e17 PP	100	* @param debug_info_dir Directory containing debug info or NULL.
	101	* @param target_prefix Path to the root file system of the target
	102	* or NULL.
d5ddf820	103	* @returns Pointer to the new bin_info on success,
c40a57e5 AB	104	* NULL on failure.
	105	*/
	106	BT_HIDDEN
d5ddf820	107	struct bin_info bin_info_create(const char path, uint64_t low_addr,
9d325e17 PP	108	uint64_t memsz, bool is_pic, const char *debug_info_dir,
9d325e17 PP	109	const char *target_prefix);
c40a57e5 AB	110
c40a57e5 AB	111	/**
d5ddf820	112	* Destroy the given bin_info instance
c40a57e5	113	*
d5ddf820	114	* @param bin bin_info instance to destroy
c40a57e5 AB	115	*/
c40a57e5 AB	116	BT_HIDDEN
d5ddf820	117	void bin_info_destroy(struct bin_info *bin);
c40a57e5 AB	118
c40a57e5 AB	119	/**
d5ddf820	120	* Sets the build ID information for a given bin_info instance.
c40a57e5	121	*
d5ddf820	122	* @param bin The bin_info instance for which to set
c40a57e5 AB	123	* the build ID
	124	* @param build_id Array of bytes containing the actual ID
	125	* @param build_id_len Length in bytes of the build_id
	126	* @returns 0 on success, -1 on failure
	127	*/
	128	BT_HIDDEN
d5ddf820	129	int bin_info_set_build_id(struct bin_info bin, uint8_t build_id,
c40a57e5 AB	130	size_t build_id_len);
	131
	132	/**
d5ddf820	133	* Sets the debug link information for a given bin_info instance.
c40a57e5	134	*
d5ddf820	135	* @param bin The bin_info instance for which to set
c40a57e5 AB	136	* the debug link
	137	* @param filename Name of the separate debug info file
	138	* @param crc Checksum for the debug info file
	139	* @returns 0 on success, -1 on failure
	140	*/
	141	BT_HIDDEN
4f45f9bb JD	142	int bin_info_set_debug_link(struct bin_info bin, const char filename,
4f45f9bb JD	143	uint32_t crc);
c40a57e5 AB	144
c40a57e5 AB	145	/**
d5ddf820 AB	146	* Returns whether or not the given bin info \p bin contains the
d5ddf820 AB	147	* address \p addr.
c40a57e5	148	*
d5ddf820	149	* @param bin bin_info instance
c40a57e5	150	* @param addr Address to lookup
d5ddf820	151	* @returns 1 if \p bin contains \p addr, 0 if it does not,
c40a57e5 AB	152	* -1 on failure
	153	*/
	154	static inline
d5ddf820	155	int bin_info_has_address(struct bin_info *bin, uint64_t addr)
c40a57e5	156	{
d5ddf820	157	if (!bin) {
c40a57e5 AB	158	return -1;
	159	}
	160
d5ddf820	161	return addr >= bin->low_addr && addr < bin->high_addr;
c40a57e5 AB	162	}
	163
	164	/**
	165	* Get the name of the function containing a given address within an
	166	* executable.
	167	*
	168	* If no DWARF info is available, the function falls back to ELF
	169	* symbols and the "function name" is in fact the name of the closest
	170	* symbol, followed by the offset between the symbol and the address.
	171	*
	172	* On success, if found, the out parameter `func_name` is set. The ownership
	173	* of `func_name` is passed to the caller. On failure, `func_name` remains
	174	* unchanged.
	175	*
d5ddf820	176	* @param bin bin_info instance for the executable containing
c40a57e5 AB	177	* the address
	178	* @param addr Virtual memory address for which to find the
	179	* function name
	180	* @param func_name Out parameter, the function name.
	181	* @returns 0 on success, -1 on failure
	182	*/
	183	BT_HIDDEN
d5ddf820	184	int bin_info_lookup_function_name(struct bin_info *bin, uint64_t addr,
c40a57e5 AB	185	char **func_name);
	186
	187	/**
	188	* Get the source location (file name and line number) for a given
	189	* address within an executable.
	190	*
	191	* If no DWARF info is available, the source location cannot be found
4caab45b	192	* and the function will return unsuccessfully.
c40a57e5 AB	193	*
	194	* On success, if found, the out parameter `src_loc` is set. The ownership
	195	* of `src_loc` is passed to the caller. On failure, `src_loc` remains
	196	* unchanged.
	197	*
d5ddf820	198	* @param bin bin_info instance for the executable containing
c40a57e5 AB	199	* the address
	200	* @param addr Virtual memory address for which to find the
	201	* source location
	202	* @param src_loc Out parameter, the source location
	203	* @returns 0 on success, -1 on failure
	204	*/
	205	BT_HIDDEN
d5ddf820	206	int bin_info_lookup_source_location(struct bin_info *bin, uint64_t addr,
c40a57e5	207	struct source_location **src_loc);
36ae9941 AB	208	/**
	209	* Get a string representing the location within the binary of a given
	210	* address.
	211	*
	212	* In the case of a PIC binary, the location is relative (+0x1234).
	213	* For a non-PIC binary, the location is absolute (@0x1234)
	214	*
	215	* On success, the out parameter `bin_loc` is set. The ownership is
	216	* passed to the caller. On failure, `bin_loc` remains unchanged.
	217	*
d5ddf820	218	* @param bin bin_info instance for the executable containing
36ae9941 AB	219	* the address
	220	* @param addr Virtual memory address for which to find the
	221	* binary location
	222	* @param bin_loc Out parameter, the binary location
	223	* @returns 0 on success, -1 on failure
	224	*/
	225	BT_HIDDEN
d5ddf820	226	int bin_info_get_bin_loc(struct bin_info bin, uint64_t addr, char *bin_loc);
c40a57e5 AB	227
	228	/**
	229	* Destroy the given source_location instance
	230	*
	231	* @param src_loc source_location instance to destroy
	232	*/
	233	BT_HIDDEN
	234	void source_location_destroy(struct source_location *src_loc);
	235
d5ddf820	236	#endif /* _BABELTRACE_BIN_INFO_H */