| 1 | #ifndef _BABELTRACE_BIN_INFO_H |
| 2 | #define _BABELTRACE_BIN_INFO_H |
| 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 | |
| 41 | struct bin_info { |
| 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 | gchar *elf_path; |
| 50 | gchar *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 | |
| 58 | /* Optional debug link info. */ |
| 59 | gchar *dbg_link_filename; |
| 60 | uint32_t dbg_link_crc; |
| 61 | /* FDs to ELF and DWARF files. */ |
| 62 | int elf_fd; |
| 63 | int dwarf_fd; |
| 64 | /* Configuration. */ |
| 65 | gchar *debug_info_dir; |
| 66 | /* Denotes whether the executable is position independent code. */ |
| 67 | bool is_pic:1; |
| 68 | /* denotes whether the build id in the trace matches to one on disk. */ |
| 69 | bool file_build_id_matches:1; |
| 70 | /* |
| 71 | * Denotes whether the executable only has ELF symbols and no |
| 72 | * DWARF info. |
| 73 | */ |
| 74 | bool is_elf_only:1; |
| 75 | }; |
| 76 | |
| 77 | struct source_location { |
| 78 | uint64_t line_no; |
| 79 | gchar *filename; |
| 80 | }; |
| 81 | |
| 82 | /** |
| 83 | * Initializes the bin_info framework. Call this before calling |
| 84 | * anything else. |
| 85 | * |
| 86 | * @returns 0 on success, -1 on failure |
| 87 | */ |
| 88 | BT_HIDDEN |
| 89 | int bin_info_init(void); |
| 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 |
| 98 | * @param is_pic Whether the executable is position independent |
| 99 | * code (PIC) |
| 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. |
| 103 | * @returns Pointer to the new bin_info on success, |
| 104 | * NULL on failure. |
| 105 | */ |
| 106 | BT_HIDDEN |
| 107 | struct bin_info *bin_info_create(const char *path, uint64_t low_addr, |
| 108 | uint64_t memsz, bool is_pic, const char *debug_info_dir, |
| 109 | const char *target_prefix); |
| 110 | |
| 111 | /** |
| 112 | * Destroy the given bin_info instance |
| 113 | * |
| 114 | * @param bin bin_info instance to destroy |
| 115 | */ |
| 116 | BT_HIDDEN |
| 117 | void bin_info_destroy(struct bin_info *bin); |
| 118 | |
| 119 | /** |
| 120 | * Sets the build ID information for a given bin_info instance. |
| 121 | * |
| 122 | * @param bin The bin_info instance for which to set |
| 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 |
| 129 | int bin_info_set_build_id(struct bin_info *bin, uint8_t *build_id, |
| 130 | size_t build_id_len); |
| 131 | |
| 132 | /** |
| 133 | * Sets the debug link information for a given bin_info instance. |
| 134 | * |
| 135 | * @param bin The bin_info instance for which to set |
| 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 |
| 142 | int bin_info_set_debug_link(struct bin_info *bin, const char *filename, |
| 143 | uint32_t crc); |
| 144 | |
| 145 | /** |
| 146 | * Returns whether or not the given bin info \p bin contains the |
| 147 | * address \p addr. |
| 148 | * |
| 149 | * @param bin bin_info instance |
| 150 | * @param addr Address to lookup |
| 151 | * @returns 1 if \p bin contains \p addr, 0 if it does not, |
| 152 | * -1 on failure |
| 153 | */ |
| 154 | static inline |
| 155 | int bin_info_has_address(struct bin_info *bin, uint64_t addr) |
| 156 | { |
| 157 | if (!bin) { |
| 158 | return -1; |
| 159 | } |
| 160 | |
| 161 | return addr >= bin->low_addr && addr < bin->high_addr; |
| 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 | * |
| 176 | * @param bin bin_info instance for the executable containing |
| 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 |
| 184 | int bin_info_lookup_function_name(struct bin_info *bin, uint64_t addr, |
| 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 |
| 192 | * and the function will return unsuccessfully. |
| 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 | * |
| 198 | * @param bin bin_info instance for the executable containing |
| 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 |
| 206 | int bin_info_lookup_source_location(struct bin_info *bin, uint64_t addr, |
| 207 | struct source_location **src_loc); |
| 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 | * |
| 218 | * @param bin bin_info instance for the executable containing |
| 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 |
| 226 | int bin_info_get_bin_loc(struct bin_info *bin, uint64_t addr, char **bin_loc); |
| 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 | |
| 236 | #endif /* _BABELTRACE_BIN_INFO_H */ |