[babeltrace.git] / include / babeltrace / 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;
	/* Denotes whether the executable is position independent code. */
	bool is_pic: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)
 * @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);

/**
 * 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, 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 unsuccesfully.
 *
 * 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
dae52e76 AB	1	#ifndef _BABELTRACE_BIN_INFO_H
dae52e76 AB	2	#define _BABELTRACE_BIN_INFO_H
b5a8598f 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
dae52e76	41	struct bin_info {
b5a8598f 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;
	57	/* Optional debug link info. */
	58	char *dbg_link_filename;
	59	uint32_t dbg_link_crc;
	60	/* FDs to ELF and DWARF files. */
	61	int elf_fd;
	62	int dwarf_fd;
	63	/* Denotes whether the executable is position independent code. */
	64	bool is_pic:1;
dae52e76 AB	65	/*
	66	* Denotes whether the executable only has ELF symbols and no
	67	* DWARF info.
	68	*/
b5a8598f AB	69	bool is_elf_only:1;
	70	};
	71
	72	struct source_location {
	73	uint64_t line_no;
	74	char *filename;
	75	};
	76
	77	/**
dae52e76	78	* Initializes the bin_info framework. Call this before calling
b5a8598f AB	79	* anything else.
	80	*
	81	* @returns 0 on success, -1 on failure
	82	*/
	83	BT_HIDDEN
dae52e76	84	int bin_info_init(void);
b5a8598f AB	85
	86	/**
	87	* Instantiate a structure representing an ELF executable, possibly
	88	* with DWARF info, located at the given path.
	89	*
	90	* @param path Path to the ELF file
	91	* @param low_addr Base address of the executable
	92	* @param memsz In-memory size of the executable
1a4a1345 AB	93	* @param is_pic Whether the executable is position independent
1a4a1345 AB	94	* code (PIC)
dae52e76	95	* @returns Pointer to the new bin_info on success,
b5a8598f AB	96	* NULL on failure.
	97	*/
	98	BT_HIDDEN
dae52e76	99	struct bin_info bin_info_create(const char path, uint64_t low_addr,
1a4a1345	100	uint64_t memsz, bool is_pic);
b5a8598f AB	101
b5a8598f AB	102	/**
dae52e76	103	* Destroy the given bin_info instance
b5a8598f	104	*
dae52e76	105	* @param bin bin_info instance to destroy
b5a8598f AB	106	*/
b5a8598f AB	107	BT_HIDDEN
dae52e76	108	void bin_info_destroy(struct bin_info *bin);
b5a8598f AB	109
b5a8598f AB	110	/**
dae52e76	111	* Sets the build ID information for a given bin_info instance.
b5a8598f	112	*
dae52e76	113	* @param bin The bin_info instance for which to set
b5a8598f AB	114	* the build ID
	115	* @param build_id Array of bytes containing the actual ID
	116	* @param build_id_len Length in bytes of the build_id
	117	* @returns 0 on success, -1 on failure
	118	*/
	119	BT_HIDDEN
dae52e76	120	int bin_info_set_build_id(struct bin_info bin, uint8_t build_id,
b5a8598f AB	121	size_t build_id_len);
	122
	123	/**
dae52e76	124	* Sets the debug link information for a given bin_info instance.
b5a8598f	125	*
dae52e76	126	* @param bin The bin_info instance for which to set
b5a8598f AB	127	* the debug link
	128	* @param filename Name of the separate debug info file
	129	* @param crc Checksum for the debug info file
	130	* @returns 0 on success, -1 on failure
	131	*/
	132	BT_HIDDEN
dae52e76	133	int bin_info_set_debug_link(struct bin_info bin, char filename, uint32_t crc);
b5a8598f AB	134
b5a8598f AB	135	/**
dae52e76 AB	136	* Returns whether or not the given bin info \p bin contains the
dae52e76 AB	137	* address \p addr.
b5a8598f	138	*
dae52e76	139	* @param bin bin_info instance
b5a8598f	140	* @param addr Address to lookup
dae52e76	141	* @returns 1 if \p bin contains \p addr, 0 if it does not,
b5a8598f AB	142	* -1 on failure
	143	*/
	144	static inline
dae52e76	145	int bin_info_has_address(struct bin_info *bin, uint64_t addr)
b5a8598f	146	{
dae52e76	147	if (!bin) {
b5a8598f AB	148	return -1;
	149	}
	150
dae52e76	151	return addr >= bin->low_addr && addr < bin->high_addr;
b5a8598f AB	152	}
	153
	154	/**
	155	* Get the name of the function containing a given address within an
	156	* executable.
	157	*
	158	* If no DWARF info is available, the function falls back to ELF
	159	* symbols and the "function name" is in fact the name of the closest
	160	* symbol, followed by the offset between the symbol and the address.
	161	*
	162	* On success, if found, the out parameter `func_name` is set. The ownership
	163	* of `func_name` is passed to the caller. On failure, `func_name` remains
	164	* unchanged.
	165	*
dae52e76	166	* @param bin bin_info instance for the executable containing
b5a8598f AB	167	* the address
	168	* @param addr Virtual memory address for which to find the
	169	* function name
	170	* @param func_name Out parameter, the function name.
	171	* @returns 0 on success, -1 on failure
	172	*/
	173	BT_HIDDEN
dae52e76	174	int bin_info_lookup_function_name(struct bin_info *bin, uint64_t addr,
b5a8598f AB	175	char **func_name);
	176
	177	/**
	178	* Get the source location (file name and line number) for a given
	179	* address within an executable.
	180	*
	181	* If no DWARF info is available, the source location cannot be found
	182	* and the function will return unsuccesfully.
	183	*
	184	* On success, if found, the out parameter `src_loc` is set. The ownership
	185	* of `src_loc` is passed to the caller. On failure, `src_loc` remains
	186	* unchanged.
	187	*
dae52e76	188	* @param bin bin_info instance for the executable containing
b5a8598f AB	189	* the address
	190	* @param addr Virtual memory address for which to find the
	191	* source location
	192	* @param src_loc Out parameter, the source location
	193	* @returns 0 on success, -1 on failure
	194	*/
	195	BT_HIDDEN
dae52e76	196	int bin_info_lookup_source_location(struct bin_info *bin, uint64_t addr,
b5a8598f	197	struct source_location **src_loc);
dc419b6c AB	198	/**
	199	* Get a string representing the location within the binary of a given
	200	* address.
	201	*
	202	* In the case of a PIC binary, the location is relative (+0x1234).
	203	* For a non-PIC binary, the location is absolute (@0x1234)
	204	*
	205	* On success, the out parameter `bin_loc` is set. The ownership is
	206	* passed to the caller. On failure, `bin_loc` remains unchanged.
	207	*
dae52e76	208	* @param bin bin_info instance for the executable containing
dc419b6c AB	209	* the address
	210	* @param addr Virtual memory address for which to find the
	211	* binary location
	212	* @param bin_loc Out parameter, the binary location
	213	* @returns 0 on success, -1 on failure
	214	*/
	215	BT_HIDDEN
dae52e76	216	int bin_info_get_bin_loc(struct bin_info bin, uint64_t addr, char *bin_loc);
b5a8598f AB	217
	218	/**
	219	* Destroy the given source_location instance
	220	*
	221	* @param src_loc source_location instance to destroy
	222	*/
	223	BT_HIDDEN
	224	void source_location_destroy(struct source_location *src_loc);
	225
dae52e76	226	#endif /* _BABELTRACE_BIN_INFO_H */