proc.h revision 6bcc092da6b7e20c6c2a9a5846536fbd3d77dbb8
1/* 2 * This file is part of ltrace. 3 * Copyright (C) 2010,2011,2012,2013,2014 Petr Machata, Red Hat Inc. 4 * Copyright (C) 2010 Joe Damato 5 * Copyright (C) 1998,2001,2008,2009 Juan Cespedes 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License as 9 * published by the Free Software Foundation; either version 2 of the 10 * License, or (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, but 13 * WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 20 * 02110-1301 USA 21 */ 22 23#ifndef _PROC_H_ 24#define _PROC_H_ 25 26#include "config.h" 27 28#include <sys/time.h> 29#include <stdint.h> 30 31#if defined(HAVE_LIBUNWIND) 32# include <libunwind.h> 33# include <libunwind-ptrace.h> 34#endif /* defined(HAVE_LIBUNWIND) */ 35 36#include "ltrace.h" 37#include "dict.h" 38#include "sysdep.h" 39#include "callback.h" 40#include "forward.h" 41 42struct event_handler { 43 /* Event handler that overrides the default one. Should 44 * return NULL if the event was handled, otherwise the 45 * returned event is passed to the default handler. */ 46 Event *(*on_event)(struct event_handler *self, Event *event); 47 48 /* Called when the event handler removal is requested. */ 49 void (*destroy)(struct event_handler *self); 50}; 51 52enum process_state { 53 STATE_ATTACHED = 0, 54 STATE_BEING_CREATED, 55 STATE_IGNORED /* ignore this process (it's a fork and no -f was used) */ 56}; 57 58struct output_state { 59 size_t params_left; 60 int need_delim; 61}; 62 63struct callstack_element { 64 union { 65 int syscall; 66 struct library_symbol * libfunc; 67 } c_un; 68 int is_syscall; 69 arch_addr_t return_addr; 70 struct timeval enter_time; 71 struct fetch_context *fetch_context; 72 struct value_dict *arguments; 73 struct output_state out; 74}; 75 76/* XXX We should get rid of this. */ 77#define MAX_CALLDEPTH 64 78 79/* XXX We would rather have this all organized a little differently, 80 * have struct process for the whole group and struct task (or struct 81 * lwp, struct thread) for what's there for per-thread stuff. But for 82 * now this is the less invasive way of structuring it. */ 83struct process { 84 enum process_state state; 85 struct process *parent; /* needed by STATE_BEING_CREATED */ 86 char * filename; 87 pid_t pid; 88 89 /* Dictionary of breakpoints (which is a mapping 90 * address->breakpoint). This is NULL for non-leader 91 * processes. */ 92 struct dict *breakpoints; 93 94 int mask_32bit; /* 1 if 64-bit ltrace is tracing 32-bit process */ 95 unsigned int personality; 96 int tracesysgood; /* signal indicating a PTRACE_SYSCALL trap */ 97 98 size_t callstack_depth; 99 struct callstack_element callstack[MAX_CALLDEPTH]; 100 101 /* Linked list of libraries in backwards order of mapping. 102 * The last element is the executed binary itself. */ 103 struct library *libraries; 104 105 /* Arch-dependent: */ 106 void * instruction_pointer; 107 void * stack_pointer; /* To get return addr, args... */ 108 void * arch_ptr; 109 110 /* XXX We would like to replace this with a pointer to ABI 111 * object that would provide the relevant services, instead of 112 * checking the necessary flags in the back end ad 113 * nauseam. */ 114 short e_machine; 115 char e_class; 116 117#if defined(HAVE_LIBUNWIND) 118 /* libunwind address space */ 119 unw_addr_space_t unwind_as; 120 void *unwind_priv; 121#endif /* defined(HAVE_LIBUNWIND) */ 122 123 /* Set in leader. */ 124 struct event_handler *event_handler; 125 126 /** 127 * Process chaining. 128 **/ 129 struct process *next; 130 131 /* LEADER points to the leader thread of the POSIX.1 process. 132 If X->LEADER == X, then X is the leader thread and the 133 process structures chained by NEXT represent other threads, 134 up until, but not including, the next leader thread. 135 LEADER may be NULL after the leader has already exited. In 136 that case this process is waiting to be collected. */ 137 struct process *leader; 138 139 struct os_process_data os; 140 struct arch_process_data arch; 141}; 142 143/* Initialize a process given a path to binary FILENAME, with a PID, 144 * and add the process to an internal chain of traced processes. */ 145int process_init(struct process *proc, const char *filename, pid_t pid); 146 147/* PROC underwent an exec. This is a bit like process_destroy 148 * followed by process_init, except that some state is kept and the 149 * process doesn't lose it's place in the list of processes. */ 150int process_exec(struct process *proc); 151 152/* Release any memory allocated for PROC (but not PROC itself). Does 153 * NOT remove PROC from internal chain. 154 * 155 * XXX clearly this init/destroy pair is different than others and 156 * should be fixed. process_init should presumably be separate from 157 * process_add. */ 158void process_destroy(struct process *proc); 159 160struct process *open_program(const char *filename, pid_t pid); 161void open_pid(pid_t pid); 162struct process *pid2proc(pid_t pid); 163 164/* Clone the contents of PROC into the memory referenced by RETP. 165 * Returns 0 on success or a negative value on failure. */ 166int process_clone(struct process *retp, struct process *proc, pid_t pid); 167 168/* Iterate through the processes that ltrace currently traces. Tasks 169 * are considered to be processes for the purpose of this iterator. 170 * See callback.h for notes on iteration interfaces. */ 171struct process *each_process(struct process *start_after, 172 enum callback_status (*cb)(struct process *proc, 173 void *data), 174 void *data); 175 176/* Iterate through list of tasks of given process PROC. See 177 * callback.h for notes on iteration interfaces. */ 178struct process *each_task(struct process *proc, struct process *start_after, 179 enum callback_status (*cb)(struct process *proc, 180 void *data), 181 void *data); 182 183void change_process_leader(struct process *proc, struct process *leader); 184 185/* Prepare those parts of process initialization that need to be done 186 * after _start is hit (i.e. after dynamic linking was done). */ 187void process_hit_start(struct process *proc); 188 189/* Remove process from the list of traced processes, drop any events 190 * in the event queue, destroy it and free memory. */ 191void remove_process(struct process *proc); 192 193void install_event_handler(struct process *proc, struct event_handler *handler); 194void destroy_event_handler(struct process *proc); 195 196/* Add a library LIB to the list of PROC's libraries. */ 197void proc_add_library(struct process *proc, struct library *lib); 198 199/* Remove LIB from list of PROC's libraries. Returns 0 if the library 200 * was found and unlinked, otherwise returns a negative value. */ 201int proc_remove_library(struct process *proc, struct library *lib); 202 203/* Clear a delayed flag. If a symbol is neither latent, nor delayed, 204 * a breakpoint is inserted for it. Returns 0 if the activation was 205 * successful or a negative value if it failed. Note that if a symbol 206 * is both latent and delayed, this will not enable the corresponding 207 * breakpoint. */ 208int proc_activate_delayed_symbol(struct process *proc, 209 struct library_symbol *libsym); 210 211/* Iterate through the libraries of PROC. See callback.h for notes on 212 * iteration interfaces. */ 213struct library *proc_each_library(struct process *proc, 214 struct library *start_after, 215 enum callback_status (*cb)(struct process *p, 216 struct library *l, 217 void *data), 218 void *data); 219 220/* Insert BP into PROC. */ 221int proc_add_breakpoint(struct process *proc, struct breakpoint *bp); 222 223/* Remove BP from PROC. This has no reason to fail in runtime. If it 224 * does not find BP in PROC, it's hard error guarded by assertion. */ 225void proc_remove_breakpoint(struct process *proc, struct breakpoint *bp); 226 227/* Iterate through the breakpoints of PROC. See callback.h for notes 228 * on iteration interfaces. */ 229arch_addr_t *proc_each_breakpoint(struct process *proc, arch_addr_t *start, 230 enum callback_status (*cb) 231 (struct process *proc, 232 struct breakpoint *bp, 233 void *data), 234 void *data); 235 236/* Iterate through the dynamic section at src_addr looking for D_TAG. 237 * If tag is found, fill it's value in RET and return 0. 238 * If tag is not found, return a negative value. */ 239int proc_find_dynamic_entry_addr(struct process *proc, arch_addr_t src_addr, 240 int d_tag, arch_addr_t *ret); 241 242/* Finds a symbol corresponding to LIBSYM in a process PROC. Returns 243 * 0 and sets *RETLIB and *RETSYM if the corresponding pointer is 244 * non-NULL. Returns a negative value when the symbols couldn't be 245 * found. */ 246int proc_find_symbol(struct process *proc, struct library_symbol *sym, 247 struct library **retlib, struct library_symbol **retsym); 248 249/* Iterate through all symbols in all libraries of PROC. See 250 * callback.h for notes on this interface. */ 251struct library_symbol *proc_each_symbol 252 (struct process *proc, struct library_symbol *start_after, 253 enum callback_status (*cb)(struct library_symbol *, void *), 254 void *data); 255 256/* Read 8, 16, 32 or 64-bit quantity located at ADDR in PROC. The 257 * resulting value is stored in *LP. 0 is returned on success or a 258 * negative value on failure. This uses umovebytes under the hood 259 * (see backend.h). */ 260int proc_read_8(struct process *proc, arch_addr_t addr, uint8_t *lp); 261int proc_read_16(struct process *proc, arch_addr_t addr, uint16_t *lp); 262int proc_read_32(struct process *proc, arch_addr_t addr, uint32_t *lp); 263int proc_read_64(struct process *proc, arch_addr_t addr, uint64_t *lp); 264 265#endif /* _PROC_H_ */ 266