1 PSYMBOL_ITER(3PROC) Process Control Library Functions PSYMBOL_ITER(3PROC) 2 3 NAME 4 Psymbol_iter, Psymbol_iter_by_addr, Psymbol_iter_by_lmid, 5 Psymbol_iter_by_name, Pxsymbol_iter - iterate symbols in a process 6 7 LIBRARY 8 Process Control Library (libproc, -lproc) 9 10 SYNOPSIS 11 #include <libproc.h> 12 13 int 14 Psymbol_iter(struct ps_prochandle *P, const char *object_name, int which, 15 int mask, proc_sym_f *func, void *data); 16 17 int 18 Psymbol_iter_by_addr(struct ps_prochandle *P, const char *object_name, 19 int which, int mask, proc_sym_f *func, void *data); 20 21 int 22 Psymbol_iter_by_lmid(struct ps_prochandle *P, Lmid_t lmid, 23 const char *object_name, int which, int mask, proc_sym_f *func, 24 void *data); 25 26 int 27 Psymbol_iter_by_name(struct ps_prochandle *P, const char *object_name, 28 int which, int mask, proc_sym_f *func, void *data); 29 30 int 31 Pxsymbol_iter(struct ps_prochandle *P, Lmid_t lmid, 32 const char *object_name, int which, int mask, proc_xsym_f *func, 33 void *data); 34 35 DESCRIPTION 36 The Psymbol_iter(), Psymbol_iter_by_addr(), Psymbol_iter_by_lmid(), 37 Psymbol_iter_by_name(), and Pxsymbol_iter() functions are used to iterate 38 over the symbols present in the process referred to by the handle P. For 39 each symbol found, the callback function func will be called once and the 40 argument data will be passed to it along with an ELF symbol entry in the 41 form of the GElf_Sym along with the name of the symbol, if known. In the 42 case of the Pxsymbol_iter() function an additional prsyminfo_t argument 43 will be provided to the callback. The definitions of proc_sym_f, 44 proc_xsym_f, and prsyminfo_t are found in libproc(3LIB). 45 46 The object_name argument names the object that is a part of the 47 controlled process which will be searched for symbols. Only one object 48 may be searched at any given time. Valid object names may be obtained 49 through the Pobjname(3PROC) and Pobject_iter(3PROC) functions, among 50 others. The system also has two special object names that may be passed 51 in to refer to the objects of the executable file and for ld.so.1. The 52 symbol PR_OBJ_EXEC refers to the executables object and the symbol 53 PR_OBJ_LDSO refers to the object ld.so.1. 54 55 The which argument controls which of two possible symbol tables will be 56 searched. If the argument is PR_SYMTAB then the ELF symbol table will be 57 searched. Otherwise, if it is PR_DYNSYM then the symbol table associated 58 with the dynamic section will be searched instead. If any other value is 59 specified for which, then an error will be returned. 60 61 The mask argument controls which symbols will be included. The mask 62 argument allows for control over both the symbol's binding and the 63 symbol's type. These flags logically correspond to the various ELF 64 symbol bindings and types. The following values may be passed as a 65 bitwise-inclusive-OR into the flags argument: 66 67 BIND_LOCAL The symbol is a local symbol. Local symbols are not 68 visible outside of their object file. 69 70 BIND_GLOBAL The symbol is a global symbol. Global symbols are 71 visible outside of their object file and may be 72 referred to by other ELF objects. 73 74 BIND_WEAK The symbol is a weak symbol. Weak symbols are 75 visible outside of their object file, but another 76 definition of the symbol may be used instead. 77 78 BIND_ANY This is a combination of BIND_LOCAL, BIND_GLOBAL, and 79 BIND_WEAK. Every symbol's binding will match this 80 value. 81 82 TYPE_NOTYPE The symbol's type is not specified. 83 84 TYPE_OBJECT The symbol refers to a data object. For example, 85 variables. 86 87 TYPE_FUNC The symbol refers to a function. 88 89 TYPE_SECTION The symbol refers to an ELF section. 90 91 TYPE_FILE The symbol refers to the name of a source file 92 associated with an object file. 93 94 TYPE_ANY This is a combination of TYPE_NOTYPE, TYPE_OBJECT, 95 TYPE_FUNC, TYPE_SECTION, and TYPE_FILE. Every 96 symbol's type will match this value. 97 98 To obtain all of the symbols in an object, the caller would pass the 99 expression BIND_ANY | TYPE_ANY in as the value of mask. 100 101 The Psymbol_iter_by_lmid() and Pxsymbol_iter() functions allow for a 102 link-map identifier to be specified in the lmid argument. This will 103 restrict the search for the object specified in object_name to the 104 specified link-map. There are three special link-map identifiers that 105 may be passed in. The symbol PR_LMID_EVERY indicates that every link-map 106 should be searched. The symbol LM_ID_BASE indicates that the base link- 107 map, the one that is used for the executable should be searched. 108 Finally, the symbol LM_ID_LDSO refers to the link-map that is used by the 109 run-time link editor, ld.so.1. The functions which do not allow a link- 110 map identifier to be specified always search every link-map. 111 112 By default, symbols are iterated based on the order of the symbol table 113 being searched. However, it is also possible to iterate based on the 114 name of the symbol and based on the address of the symbol. To iterate by 115 name use the Psymbol_iter_by_name() function. To iterate by address use 116 the Psymbol_iter_by_addr() function. The Psymbol_iter(), 117 Psymbol_iter_by_lmid(), and Pxsymbol_iter() functions all sort based on 118 the order of the symbol table. 119 120 The return value of the callback function func determines whether or not 121 iteration continues. If func returns 0, then iteration will continue. 122 However, if func returns non-zero, then iteration will halt and that 123 value will be used as the return value of the Psymbol_iter(), 124 Psymbol_iter_by_addr(), Psymbol_iter_by_lmid(), Psymbol_iter_by_name(), 125 and Pxsymbol_iter() functions. Because these functions return -1 on 126 internal failure, it is recommended that the callback function not return 127 -1 to indicate an error so that the caller may distinguish between the 128 failure of the callback function and the failure of these functions. 129 130 RETURN VALUES 131 Upon successful completion, the Psymbol_iter(), Psymbol_iter_by_addr(), 132 Psymbol_iter_by_lmid(), Psymbol_iter_by_name(), and Pxsymbol_iter() 133 functions return 0. If there was an internal error then -1 is returned. 134 Otherwise, if the callback function func returns non-zero, then its 135 return value will be returned instead. 136 137 INTERFACE STABILITY 138 Uncommitted 139 140 MT-LEVEL 141 See LOCKING in libproc(3LIB). 142 143 SEE ALSO 144 elf(3ELF), gelf(3ELF), libproc(3LIB), proc(4) 145 146 illumos May 11, 2016 illumos