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proc.c
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proc.c
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/*
* This file is part of ltrace.
* Copyright (C) 2011,2012,2013,2014 Petr Machata, Red Hat Inc.
* Copyright (C) 2010 Joe Damato
* Copyright (C) 1998,2009 Juan Cespedes
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*/
#include "config.h"
#include <sys/types.h>
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "backend.h"
#include "breakpoint.h"
#include "debug.h"
#include "fetch.h"
#include "options.h"
#include "proc.h"
#include "value_dict.h"
#if defined(HAVE_LIBDW)
# include "dwarf_prototypes.h"
#endif /* defined(HAVE_LIBDW) */
#ifndef OS_HAVE_PROCESS_DATA
int
os_process_init(struct process *proc)
{
return 0;
}
void
os_process_destroy(struct process *proc)
{
}
int
os_process_clone(struct process *retp, struct process *proc)
{
return 0;
}
int
os_process_exec(struct process *proc)
{
return 0;
}
#endif
#ifndef ARCH_HAVE_PROCESS_DATA
int
arch_process_init(struct process *proc)
{
return 0;
}
void
arch_process_destroy(struct process *proc)
{
}
int
arch_process_clone(struct process *retp, struct process *proc)
{
return 0;
}
int
arch_process_exec(struct process *proc)
{
return 0;
}
#endif
#ifndef ARCH_HAVE_DYNLINK_DONE
void
arch_dynlink_done(struct process *proc)
{
}
#endif
static int add_process(struct process *proc, int was_exec);
static void unlist_process(struct process *proc);
static void
destroy_unwind(struct process *proc)
{
#if defined(HAVE_LIBUNWIND)
if (proc->unwind_priv != NULL)
_UPT_destroy(proc->unwind_priv);
if (proc->unwind_as != NULL)
unw_destroy_addr_space(proc->unwind_as);
#endif /* defined(HAVE_LIBUNWIND) */
#if defined(HAVE_LIBDW)
if (proc->dwfl != NULL)
dwfl_end(proc->dwfl);
#endif /* defined(HAVE_LIBDW) */
}
static int
process_bare_init(struct process *proc, const char *filename,
pid_t pid, int was_exec)
{
if (!was_exec) {
memset(proc, 0, sizeof(*proc));
proc->filename = strdup(filename);
if (proc->filename == NULL) {
fail:
free(proc->filename);
if (proc->breakpoints != NULL) {
dict_destroy(proc->breakpoints,
NULL, NULL, NULL);
free(proc->breakpoints);
proc->breakpoints = NULL;
}
return -1;
}
}
/* Add process so that we know who the leader is. */
proc->pid = pid;
if (add_process(proc, was_exec) < 0)
goto fail;
if (proc->leader == NULL) {
unlist_and_fail:
if (!was_exec)
unlist_process(proc);
goto fail;
}
if (proc->leader == proc) {
proc->breakpoints = malloc(sizeof(*proc->breakpoints));
if (proc->breakpoints == NULL)
goto unlist_and_fail;
DICT_INIT(proc->breakpoints,
arch_addr_t, struct breakpoint *,
arch_addr_hash, arch_addr_eq, NULL);
} else {
proc->breakpoints = NULL;
}
#if defined(HAVE_LIBUNWIND)
if (options.bt_depth > 0) {
proc->unwind_priv = _UPT_create(pid);
proc->unwind_as = unw_create_addr_space(&_UPT_accessors, 0);
if (proc->unwind_priv == NULL || proc->unwind_as == NULL) {
fprintf(stderr,
"Couldn't initialize unwinding "
"for process %d\n", proc->pid);
destroy_unwind(proc);
proc->unwind_priv = NULL;
proc->unwind_as = NULL;
}
}
#endif /* defined(HAVE_LIBUNWIND) */
#if defined(HAVE_LIBDW)
proc->dwfl = NULL; /* Initialize for leader only on first library. */
proc->should_attach_dwfl = 1; /* should try to attach the DWFL data */
#endif /* defined(HAVE_LIBDW) */
return 0;
}
static void
process_bare_destroy(struct process *proc, int was_exec)
{
dict_destroy(proc->breakpoints, NULL, NULL, NULL);
free(proc->breakpoints);
if (!was_exec) {
free(proc->filename);
unlist_process(proc);
destroy_unwind(proc);
}
}
static int
process_init_main(struct process *proc)
{
if (breakpoints_init(proc) < 0) {
fprintf(stderr, "failed to init breakpoints %d\n",
proc->pid);
return -1;
}
return 0;
}
int
process_init(struct process *proc, const char *filename, pid_t pid)
{
if (process_bare_init(proc, filename, pid, 0) < 0) {
fail:
fprintf(stderr, "failed to initialize process %d: %s\n",
pid, strerror(errno));
return -1;
}
if (os_process_init(proc) < 0) {
process_bare_destroy(proc, 0);
goto fail;
}
if (arch_process_init(proc) < 0) {
os_process_destroy(proc);
process_bare_destroy(proc, 0);
goto fail;
}
if (proc->leader != proc) {
proc->e_machine = proc->leader->e_machine;
proc->e_class = proc->leader->e_class;
get_arch_dep(proc);
} else if (process_init_main(proc) < 0) {
process_bare_destroy(proc, 0);
goto fail;
}
return 0;
}
static enum callback_status
destroy_breakpoint_cb(struct process *proc, struct breakpoint *bp, void *data)
{
breakpoint_destroy(bp);
free(bp);
return CBS_CONT;
}
// XXX see comment in handle_event.c
void callstack_pop(struct process *proc);
static void
private_process_destroy(struct process *proc, int was_exec)
{
/* Pop remaining stack elements. */
while (proc->callstack_depth > 0) {
/* When this is called just before a process is
* destroyed, the breakpoints should either have been
* retracted by now, or were killed by exec. In any
* case, it's safe to pretend that there are no
* breakpoints associated with the stack elements, so
* that stack_pop doesn't attempt to destroy them. */
size_t i = proc->callstack_depth - 1;
if (!proc->callstack[i].is_syscall)
proc->callstack[i].return_addr = 0;
callstack_pop(proc);
}
if (!was_exec)
free(proc->filename);
/* Libraries and symbols. This is only relevant in
* leader. */
struct library *lib;
for (lib = proc->libraries; lib != NULL; ) {
struct library *next = lib->next;
library_destroy(lib);
free(lib);
lib = next;
}
proc->libraries = NULL;
/* Breakpoints. */
if (proc->breakpoints != NULL) {
proc_each_breakpoint(proc, NULL, destroy_breakpoint_cb, NULL);
dict_destroy(proc->breakpoints, NULL, NULL, NULL);
free(proc->breakpoints);
proc->breakpoints = NULL;
}
destroy_unwind(proc);
}
void
process_destroy(struct process *proc)
{
arch_process_destroy(proc);
os_process_destroy(proc);
private_process_destroy(proc, 0);
}
int
process_exec(struct process *proc)
{
/* Call exec handlers first, before we destroy the main
* state. */
if (arch_process_exec(proc) < 0
|| os_process_exec(proc) < 0)
return -1;
private_process_destroy(proc, 1);
if (process_bare_init(proc, NULL, proc->pid, 1) < 0)
return -1;
if (process_init_main(proc) < 0) {
process_bare_destroy(proc, 1);
return -1;
}
return 0;
}
struct process *
open_program(const char *filename, pid_t pid)
{
assert(pid != 0);
struct process *proc = malloc(sizeof(*proc));
if (proc == NULL || process_init(proc, filename, pid) < 0) {
free(proc);
return NULL;
}
return proc;
}
struct clone_single_bp_data {
struct process *old_proc;
struct process *new_proc;
};
static enum callback_status
clone_single_bp(arch_addr_t *key, struct breakpoint **bpp, void *u)
{
struct breakpoint *bp = *bpp;
struct clone_single_bp_data *data = u;
struct breakpoint *clone = malloc(sizeof(*clone));
if (clone == NULL
|| breakpoint_clone(clone, data->new_proc, bp) < 0) {
fail:
free(clone);
return CBS_STOP;
}
if (proc_add_breakpoint(data->new_proc->leader, clone) < 0) {
breakpoint_destroy(clone);
goto fail;
}
return CBS_CONT;
}
int
process_clone(struct process *retp, struct process *proc, pid_t pid)
{
if (process_bare_init(retp, proc->filename, pid, 0) < 0) {
fail1:
fprintf(stderr, "Failed to clone process %d to %d: %s\n",
proc->pid, pid, strerror(errno));
return -1;
}
retp->tracesysgood = proc->tracesysgood;
retp->e_machine = proc->e_machine;
retp->e_class = proc->e_class;
/* For non-leader processes, that's all we need to do. */
if (retp->leader != retp)
return 0;
/* Clone symbols first so that we can clone and relink
* breakpoints. */
struct library *lib;
struct library **nlibp = &retp->libraries;
for (lib = proc->leader->libraries; lib != NULL; lib = lib->next) {
*nlibp = malloc(sizeof(**nlibp));
if (*nlibp == NULL
|| library_clone(*nlibp, lib) < 0) {
free(*nlibp);
*nlibp = NULL;
fail2:
process_bare_destroy(retp, 0);
/* Error when cloning. Unroll what was done. */
for (lib = retp->libraries; lib != NULL; ) {
struct library *next = lib->next;
library_destroy(lib);
free(lib);
lib = next;
}
goto fail1;
}
nlibp = &(*nlibp)->next;
}
/* Now clone breakpoints. Symbol relinking is done in
* clone_single_bp. */
struct clone_single_bp_data data = {
.old_proc = proc,
.new_proc = retp,
};
if (DICT_EACH(proc->leader->breakpoints,
arch_addr_t, struct breakpoint *, NULL,
clone_single_bp, &data) != NULL)
goto fail2;
/* And finally the call stack. */
/* XXX clearly the callstack handling should be moved to a
* separate module and this whole business extracted to
* callstack_clone, or callstack_element_clone. */
memcpy(retp->callstack, proc->callstack, sizeof(retp->callstack));
retp->callstack_depth = proc->callstack_depth;
size_t i;
for (i = 0; i < retp->callstack_depth; ++i) {
struct callstack_element *elem = &retp->callstack[i];
struct fetch_context *ctx = elem->fetch_context;
if (ctx != NULL) {
struct fetch_context *nctx = fetch_arg_clone(retp, ctx);
if (nctx == NULL) {
size_t j;
fail3:
for (j = 0; j < i; ++j) {
nctx = retp->callstack[j].fetch_context;
fetch_arg_done(nctx);
elem->fetch_context = NULL;
}
goto fail2;
}
elem->fetch_context = nctx;
}
if (elem->arguments != NULL) {
struct value_dict *nargs = malloc(sizeof(*nargs));
if (nargs == NULL
|| val_dict_clone(nargs, elem->arguments) < 0) {
size_t j;
for (j = 0; j < i; ++j) {
nargs = retp->callstack[j].arguments;
val_dict_destroy(nargs);
free(nargs);
elem->arguments = NULL;
}
/* Pretend that this round went well,
* so that fail3 frees I-th
* fetch_context. */
++i;
goto fail3;
}
elem->arguments = nargs;
}
/* If it's not a syscall, we need to find the
* corresponding library symbol in the cloned
* library. */
if (!elem->is_syscall && elem->c_un.libfunc != NULL) {
struct library_symbol *libfunc = elem->c_un.libfunc;
int rc = proc_find_symbol(retp, libfunc,
NULL, &elem->c_un.libfunc);
assert(rc == 0);
}
}
/* At this point, retp is fully initialized, except for OS and
* arch parts, and we can call private_process_destroy. */
if (os_process_clone(retp, proc) < 0) {
private_process_destroy(retp, 0);
return -1;
}
if (arch_process_clone(retp, proc) < 0) {
os_process_destroy(retp);
private_process_destroy(retp, 0);
return -1;
}
return 0;
}
static int
open_one_pid(pid_t pid)
{
debug(DEBUG_PROCESS, "open_one_pid(pid=%d)", pid);
/* Get the filename first. Should the trace_pid fail, we can
* easily free it, untracing is more work. */
char *filename = pid2name(pid);
if (filename == NULL || trace_pid(pid) < 0) {
fail:
free(filename);
return -1;
}
struct process *proc = open_program(filename, pid);
if (proc == NULL)
goto fail;
free(filename);
trace_set_options(proc);
return 0;
}
static enum callback_status
start_one_pid(struct process *proc, void *data)
{
continue_process(proc->pid);
return CBS_CONT;
}
static enum callback_status
is_main(struct process *proc, struct library *lib, void *data)
{
return CBS_STOP_IF(lib->type == LT_LIBTYPE_MAIN);
}
void
process_hit_start(struct process *proc)
{
struct process *leader = proc->leader;
assert(leader != NULL);
struct library *mainlib
= proc_each_library(leader, NULL, is_main, NULL);
assert(mainlib != NULL);
linkmap_init(leader, mainlib->dyn_addr);
arch_dynlink_done(leader);
}
void
open_pid(pid_t pid)
{
debug(DEBUG_PROCESS, "open_pid(pid=%d)", pid);
/* If we are already tracing this guy, we should be seeing all
* his children via normal tracing route. */
if (pid2proc(pid) != NULL)
return;
/* First, see if we can attach the requested PID itself. */
if (open_one_pid(pid) < 0) {
fprintf(stderr, "Cannot attach to pid %u: %s\n",
pid, strerror(errno));
trace_fail_warning(pid);
return;
}
/* Now attach to all tasks that belong to that PID. There's a
* race between process_tasks and open_one_pid. So when we
* fail in open_one_pid below, we just do another round.
* Chances are that by then that PID will have gone away, and
* that's why we have seen the failure. The processes that we
* manage to open_one_pid are stopped, so we should eventually
* reach a point where process_tasks doesn't give any new
* processes (because there's nobody left to produce
* them). */
size_t old_ntasks = 0;
int have_all;
while (1) {
pid_t *tasks;
size_t ntasks;
size_t i;
if (process_tasks(pid, &tasks, &ntasks) < 0) {
fprintf(stderr, "Cannot obtain tasks of pid %u: %s\n",
pid, strerror(errno));
break;
}
have_all = 1;
for (i = 0; i < ntasks; ++i)
if (pid2proc(tasks[i]) == NULL
&& open_one_pid(tasks[i]) < 0)
have_all = 0;
free(tasks);
if (have_all && old_ntasks == ntasks)
break;
old_ntasks = ntasks;
}
struct process *leader = pid2proc(pid)->leader;
/* XXX Is there a way to figure out whether _start has
* actually already been hit? */
process_hit_start(leader);
/* Done. Continue everyone. */
each_task(leader, NULL, start_one_pid, NULL);
}
static enum callback_status
find_proc(struct process *proc, void *data)
{
return CBS_STOP_IF(proc->pid == (pid_t)(uintptr_t)data);
}
struct process *
pid2proc(pid_t pid)
{
return each_process(NULL, &find_proc, (void *)(uintptr_t)pid);
}
static struct process *list_of_processes = NULL;
static void
unlist_process(struct process *proc)
{
if (list_of_processes == proc) {
list_of_processes = list_of_processes->next;
return;
}
struct process *tmp;
for (tmp = list_of_processes; ; tmp = tmp->next) {
/* If the following assert fails, the process wasn't
* in the list. */
assert(tmp->next != NULL);
if (tmp->next == proc) {
tmp->next = tmp->next->next;
return;
}
}
}
struct process *
each_process(struct process *start_after,
enum callback_status(*cb)(struct process *proc, void *data),
void *data)
{
struct process *it = start_after == NULL ? list_of_processes
: start_after->next;
while (it != NULL) {
/* Callback might call remove_process. */
struct process *next = it->next;
switch ((*cb)(it, data)) {
case CBS_FAIL:
/* XXX handle me */
case CBS_STOP:
return it;
case CBS_CONT:
break;
}
it = next;
}
return NULL;
}
struct process *
each_task(struct process *proc, struct process *start_after,
enum callback_status(*cb)(struct process *proc, void *data),
void *data)
{
assert(proc != NULL);
struct process *it = start_after == NULL ? proc->leader
: start_after->next;
if (it != NULL) {
struct process *leader = it->leader;
while (it != NULL && it->leader == leader) {
/* Callback might call remove_process. */
struct process *next = it->next;
switch ((*cb)(it, data)) {
case CBS_FAIL:
/* XXX handle me */
case CBS_STOP:
return it;
case CBS_CONT:
break;
}
it = next;
}
}
return NULL;
}
static int
add_process(struct process *proc, int was_exec)
{
struct process **leaderp = &list_of_processes;
if (proc->pid) {
pid_t tgid = process_leader(proc->pid);
if (tgid == 0)
/* Must have been terminated before we managed
* to fully attach. */
return -1;
if (tgid == proc->pid) {
proc->leader = proc;
} else {
struct process *leader = pid2proc(tgid);
proc->leader = leader;
if (leader != NULL)
leaderp = &leader->next;
}
}
if (!was_exec) {
proc->next = *leaderp;
*leaderp = proc;
}
return 0;
}
void
change_process_leader(struct process *proc, struct process *leader)
{
struct process **leaderp = &list_of_processes;
if (proc->leader == leader)
return;
assert(leader != NULL);
unlist_process(proc);
if (proc != leader)
leaderp = &leader->next;
proc->leader = leader;
proc->next = *leaderp;
*leaderp = proc;
}
static enum callback_status
clear_leader(struct process *proc, void *data)
{
debug(DEBUG_FUNCTION, "detach_task %d from leader %d",
proc->pid, proc->leader->pid);
proc->leader = NULL;
return CBS_CONT;
}
void
remove_process(struct process *proc)
{
debug(DEBUG_FUNCTION, "remove_proc(pid=%d)", proc->pid);
if (proc->leader == proc)
each_task(proc, NULL, &clear_leader, NULL);
unlist_process(proc);
process_removed(proc);
process_destroy(proc);
free(proc);
}
void
install_event_handler(struct process *proc, struct event_handler *handler)
{
debug(DEBUG_FUNCTION, "install_event_handler(pid=%d, %p)", proc->pid, handler);
assert(proc->event_handler == NULL);
proc->event_handler = handler;
}
void
destroy_event_handler(struct process *proc)
{
struct event_handler *handler = proc->event_handler;
debug(DEBUG_FUNCTION, "destroy_event_handler(pid=%d, %p)", proc->pid, handler);
assert(handler != NULL);
if (handler->destroy != NULL)
handler->destroy(handler);
free(handler);
proc->event_handler = NULL;
}
static int
breakpoint_for_symbol(struct library_symbol *libsym, struct process *proc)
{
arch_addr_t bp_addr;
assert(proc->leader == proc);
/* Don't enable latent or delayed symbols. */
if (libsym->latent || libsym->delayed) {
debug(DEBUG_FUNCTION,
"delayed and/or latent breakpoint pid=%d, %s@%p",
proc->pid, libsym->name, libsym->enter_addr);
return 0;
}
bp_addr = sym2addr(proc, libsym);
/* If there is an artificial breakpoint on the same address,
* its libsym will be NULL, and we can smuggle our libsym
* there. That artificial breakpoint is there presumably for
* the callbacks, which we don't touch. If there is a real
* breakpoint, then this is a bug. ltrace-elf.c should filter
* symbols and ignore extra symbol aliases.
*
* The other direction is more complicated and currently not
* supported. If a breakpoint has custom callbacks, it might
* be also custom-allocated, and we would really need to swap
* the two: delete the one now in the dictionary, swap values
* around, and put the new breakpoint back in. */
struct breakpoint *bp;
if (DICT_FIND_VAL(proc->breakpoints, &bp_addr, &bp) == 0) {
/* MIPS backend makes duplicate requests. This is
* likely a bug in the backend. Currently there's no
* point assigning more than one symbol to a
* breakpoint, because when it hits, we won't know
* what to print out. But it's easier to fix it here
* before someone who understands MIPS has the time to
* look into it. So turn the sanity check off on
* MIPS. References:
*
* http://lists.alioth.debian.org/pipermail/ltrace-devel/2012-November/000764.html
* http://lists.alioth.debian.org/pipermail/ltrace-devel/2012-November/000770.html
*/
#ifndef __mips__
assert(bp->libsym == NULL);
bp->libsym = libsym;
#endif
return 0;
}
bp = malloc(sizeof(*bp));
if (bp == NULL
|| breakpoint_init(bp, proc, bp_addr, libsym) < 0) {
fail:
free(bp);
return -1;
}
if (proc_add_breakpoint(proc, bp) < 0) {
breakpoint_destroy(bp);
goto fail;
}
if (breakpoint_turn_on(bp, proc) < 0) {
proc_remove_breakpoint(proc, bp);
breakpoint_destroy(bp);
goto fail;
}
return 0;
}
static enum callback_status
cb_breakpoint_for_symbol(struct library_symbol *libsym, void *data)
{
return CBS_STOP_IF(breakpoint_for_symbol(libsym, data) < 0);
}
static int
proc_activate_latent_symbol(struct process *proc,
struct library_symbol *libsym)
{
assert(libsym->latent);
libsym->latent = 0;
debug(DEBUG_FUNCTION, "activated latent symbol");
return breakpoint_for_symbol(libsym, proc);
}
int
proc_activate_delayed_symbol(struct process *proc,
struct library_symbol *libsym)
{
assert(libsym->delayed);
libsym->delayed = 0;
debug(DEBUG_FUNCTION, "activated delayed symbol");
return breakpoint_for_symbol(libsym, proc);
}
struct activate_latent_in_context
{
struct process *proc;
struct library_exported_names *exported_names;
};
static enum callback_status
activate_latent_in_cb(struct library_symbol *libsym, void *data)
{
struct activate_latent_in_context *ctx =
(struct activate_latent_in_context*)data;
if (libsym->latent &&
library_exported_names_contains(ctx->exported_names,
libsym->name) != 0)
proc_activate_latent_symbol(ctx->proc, libsym);
return CBS_CONT;
}
static enum callback_status
activate_latent_in(struct process *proc, struct library *lib, void *data)
{
struct library_symbol *libsym = NULL;
struct library_exported_names *exported_names =
(struct library_exported_names*)data;
struct activate_latent_in_context ctx =
{.proc = proc,
.exported_names = exported_names};
if (library_each_symbol(lib, libsym,
activate_latent_in_cb,
&ctx) != NULL)
return CBS_FAIL;
return CBS_CONT;
}
void
proc_add_library(struct process *proc, struct library *lib)
{
assert(lib->next == NULL);
lib->next = proc->libraries;
proc->libraries = lib;
debug(DEBUG_PROCESS, "added library %s@%p (%s) to %d",
lib->soname, lib->base, lib->pathname, proc->pid);
#if defined(HAVE_LIBDW)
Dwfl *dwfl = NULL;
Dwfl_Module *dwfl_module = NULL;
/* Setup module tracking for libdwfl unwinding. */
struct process *leader = proc->leader;
dwfl = leader->dwfl;
if (dwfl == NULL) {
static const Dwfl_Callbacks proc_callbacks = {
.find_elf = dwfl_linux_proc_find_elf,
.find_debuginfo = dwfl_standard_find_debuginfo
};
dwfl = dwfl_begin(&proc_callbacks);
if (dwfl == NULL)
fprintf(stderr,
"Couldn't initialize libdwfl unwinding "
"for process %d: %s\n", leader->pid,
dwfl_errmsg (-1));
}
if (dwfl != NULL) {
dwfl_report_begin_add(dwfl);
dwfl_module =
dwfl_report_elf(dwfl, lib->soname,
lib->pathname, -1,
/* XXX double cast */
(GElf_Addr) (uintptr_t) lib->base,
false);
if (dwfl_module == NULL)
fprintf(stderr,
"dwfl_report_elf %s@%p (%s) %d: %s\n",
lib->soname, lib->base, lib->pathname,
proc->pid, dwfl_errmsg (-1));
dwfl_report_end(dwfl, NULL, NULL);
if (options.bt_depth > 0) {
if (proc->should_attach_dwfl) {
int r = dwfl_linux_proc_attach(dwfl,
leader->pid,
true);
proc->should_attach_dwfl = 0;
if (r != 0) {
const char *msg;
dwfl_end(dwfl);
if (r < 0)
msg = dwfl_errmsg(-1);
else
msg = strerror(r);
fprintf(stderr, "Couldn't initialize "
"libdwfl (unwinding, prototype "
"import) for process %d: %s\n",
leader->pid, msg);
}
}
}
}
lib->dwfl_module = dwfl_module;
leader->dwfl = dwfl;
#endif /* defined(HAVE_LIBDW) */
/* Insert breakpoints for all active (non-latent) symbols. */
struct library_symbol *libsym = NULL;
while ((libsym = library_each_symbol(lib, libsym,
cb_breakpoint_for_symbol,
proc)) != NULL)
fprintf(stderr,
"Couldn't insert breakpoint for %s to %d: %s.\n",
libsym->name, proc->pid, strerror(errno));
if (lib->should_activate_latent != 0) {
/* Look through export list of the new library and compare it
* with latent symbols of all libraries (including this
* library itself). */
struct library *lib2 = NULL;
while ((lib2 = proc_each_library(proc, lib2, activate_latent_in,