1 /* 2 * Copyright (c) 2016 GitHub, Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 #ifndef LIBBCC_SYMS_H 17 #define LIBBCC_SYMS_H 18 19 #ifdef __cplusplus 20 extern "C" { 21 #endif 22 23 #include <stdint.h> 24 25 struct bcc_symbol { 26 const char *name; 27 const char *demangle_name; 28 const char *module; 29 uint64_t offset; 30 }; 31 32 typedef int (*SYM_CB)(const char *symname, uint64_t addr); 33 34 #ifndef STT_GNU_IFUNC 35 #define STT_GNU_IFUNC 10 36 #endif 37 38 #if defined(__powerpc64__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__ 39 // Indicate if the Local Entry Point (LEP) should be used as a symbol's 40 // start address 41 #define STT_PPC64LE_SYM_LEP 31 42 #endif 43 44 static const uint32_t BCC_SYM_ALL_TYPES = 65535; 45 struct bcc_symbol_option { 46 int use_debug_file; 47 int check_debug_file_crc; 48 // Bitmask flags indicating what types of ELF symbols to use 49 uint32_t use_symbol_type; 50 }; 51 52 void *bcc_symcache_new(int pid, struct bcc_symbol_option *option); 53 void bcc_free_symcache(void *symcache, int pid); 54 55 // The demangle_name pointer in bcc_symbol struct is returned from the 56 // __cxa_demangle function call, which is supposed to be freed by caller. Call 57 // this function after done using returned result of bcc_symcache_resolve. 58 void bcc_symbol_free_demangle_name(struct bcc_symbol *sym); 59 int bcc_symcache_resolve(void *symcache, uint64_t addr, struct bcc_symbol *sym); 60 int bcc_symcache_resolve_no_demangle(void *symcache, uint64_t addr, 61 struct bcc_symbol *sym); 62 63 int bcc_symcache_resolve_name(void *resolver, const char *module, 64 const char *name, uint64_t *addr); 65 void bcc_symcache_refresh(void *resolver); 66 67 int bcc_resolve_global_addr(int pid, const char *module, const uint64_t address, 68 uint64_t *global); 69 70 // Call cb on every function symbol in the specified module. Uses simpler 71 // SYM_CB callback mainly for easier to use in Python API. 72 // Will prefer use debug file and check debug file CRC when reading the module. 73 int bcc_foreach_function_symbol(const char *module, SYM_CB cb); 74 75 // Find the offset of a symbol in a module binary. If addr is not zero, will 76 // calculate the offset using the provided addr and the module's load address. 77 // 78 // If pid is provided, will use it to help lookup the module in the Process and 79 // enter the Process's mount Namespace. 80 // 81 // If option is not NULL, will respect the specified options for lookup. 82 // Otherwise default option will apply, which is to use debug file, verify 83 // checksum, and try all types of symbols. 84 // 85 // Return 0 on success and -1 on failure. Output will be write to sym. After 86 // use, sym->module need to be freed if it's not empty. 87 int bcc_resolve_symname(const char *module, const char *symname, 88 const uint64_t addr, int pid, 89 struct bcc_symbol_option* option, 90 struct bcc_symbol *sym); 91 92 #ifdef __cplusplus 93 } 94 #endif 95 #endif 96