+/*
+ * 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 <string.h>
-#include <stdio.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);
-#include "common.h"
+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;
-Process *
-open_program(char *filename, pid_t pid) {
- Process *proc;
- proc = calloc(sizeof(Process), 1);
- if (!proc) {
- perror("malloc");
- exit(1);
+ callstack_pop(proc);
}
- proc->filename = strdup(filename);
- proc->breakpoints_enabled = -1;
- if (pid) {
- proc->pid = pid;
+
+ 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;
}
- breakpoints_init(proc);
+ 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);
+}
- proc->next = list_of_processes;
- list_of_processes = proc;
+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) {
- Process *proc;
- char *filename;
+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);
+}
- if (trace_pid(pid) < 0) {
- fprintf(stderr, "Cannot attach to pid %u: %s\n", pid,
- strerror(errno));
+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;
}
- filename = pid2name(pid);
+ 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;
- if (!filename) {
- fprintf(stderr, "Cannot trace pid %u: %s\n", pid,
- strerror(errno));
+ 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));
}
- proc = open_program(filename, pid);
- continue_process(pid);
- proc->breakpoints_enabled = 1;
+ if (dwfl != NULL) {
+ dwfl_report_begin_add(dwfl);
+ dwfl_module =
+ dwfl_report_elf(dwfl, lib->soname,
+ lib->pathname, -1,
+ (GElf_Addr) 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,
+ &lib->exported_names)) != NULL)
+ fprintf(stderr,
+ "Couldn't activate latent symbols "
+ "for %s in %d: %s.\n",
+ lib2->soname, proc->pid, strerror(errno));
+ }
}
-Process *
-pid2proc(pid_t pid) {
- Process *tmp;
+int
+proc_remove_library(struct process *proc, struct library *lib)
+{
+ struct library **libp;
+ for (libp = &proc->libraries; *libp != NULL; libp = &(*libp)->next)
+ if (*libp == lib) {
+ *libp = lib->next;
+ return 0;
+ }
+ return -1;
+}
+
+struct library *
+proc_each_library(struct process *proc, struct library *it,
+ enum callback_status (*cb)(struct process *proc,
+ struct library *lib, void *data),
+ void *data)
+{
+ if (it == NULL)
+ it = proc->libraries;
+ else
+ it = it->next;
+
+ while (it != NULL) {
+ struct library *next = it->next;
- tmp = list_of_processes;
- while (tmp) {
- if (pid == tmp->pid) {
- return tmp;
+ switch (cb(proc, it, data)) {
+ case CBS_FAIL:
+ /* XXX handle me */
+ case CBS_STOP:
+ return it;
+ case CBS_CONT:
+ break;
}
- tmp = tmp->next;
+
+ it = next;
}
+
return NULL;
}
+
+static void
+check_leader(struct process *proc)
+{
+ /* Only the group leader should be getting the breakpoints and
+ * thus have ->breakpoint initialized. */
+ assert(proc->leader != NULL);
+ assert(proc->leader == proc);
+ assert(proc->breakpoints != NULL);
+}
+
+int
+proc_add_breakpoint(struct process *proc, struct breakpoint *bp)
+{
+ debug(DEBUG_FUNCTION, "proc_add_breakpoint(pid=%d, %s@%p)",
+ proc->pid, breakpoint_name(bp), bp->addr);
+ check_leader(proc);
+
+ /* XXX We might merge bp->libsym instead of the following
+ * assert, but that's not necessary right now. Read the
+ * comment in breakpoint_for_symbol. */
+ assert(dict_find(proc->breakpoints, &bp->addr) == NULL);
+
+ if (DICT_INSERT(proc->breakpoints, &bp->addr, &bp) < 0) {
+ fprintf(stderr,
+ "couldn't enter breakpoint %s@%p to dictionary: %s\n",
+ breakpoint_name(bp), bp->addr, strerror(errno));
+ return -1;
+ }
+
+ return 0;
+}
+
+void
+proc_remove_breakpoint(struct process *proc, struct breakpoint *bp)
+{
+ debug(DEBUG_FUNCTION, "proc_remove_breakpoint(pid=%d, %s@%p)",
+ proc->pid, breakpoint_name(bp), bp->addr);
+ check_leader(proc);
+ int rc = DICT_ERASE(proc->breakpoints, &bp->addr, struct breakpoint *,
+ NULL, NULL, NULL);
+ assert(rc == 0);
+}
+
+struct each_breakpoint_data
+{
+ struct process *proc;
+ enum callback_status (*cb)(struct process *proc,
+ struct breakpoint *bp,
+ void *data);
+ void *cb_data;
+};
+
+static enum callback_status
+each_breakpoint_cb(arch_addr_t *key, struct breakpoint **bpp, void *d)
+{
+ struct each_breakpoint_data *data = d;
+ return data->cb(data->proc, *bpp, data->cb_data);
+}
+
+arch_addr_t *
+proc_each_breakpoint(struct process *proc, arch_addr_t *start,
+ enum callback_status (*cb)(struct process *proc,
+ struct breakpoint *bp,
+ void *data), void *data)
+{
+ struct each_breakpoint_data dd = {
+ .proc = proc,
+ .cb = cb,
+ .cb_data = data,
+ };
+ return DICT_EACH(proc->breakpoints,
+ arch_addr_t, struct breakpoint *, start,
+ &each_breakpoint_cb, &dd);
+}
+
+int
+proc_find_symbol(struct process *proc, struct library_symbol *sym,
+ struct library **retlib, struct library_symbol **retsym)
+{
+ struct library *lib = sym->lib;
+ assert(lib != NULL);
+
+ struct library *flib
+ = proc_each_library(proc, NULL, library_with_key_cb, &lib->key);
+ if (flib == NULL)
+ return -1;
+
+ struct library_symbol *fsym
+ = library_each_symbol(flib, NULL, library_symbol_named_cb,
+ (char *)sym->name);
+ if (fsym == NULL)
+ return -1;
+
+ if (retlib != NULL)
+ *retlib = flib;
+ if (retsym != NULL)
+ *retsym = fsym;
+
+ return 0;
+}
+
+struct library_symbol *
+proc_each_symbol(struct process *proc, struct library_symbol *start_after,
+ enum callback_status (*cb)(struct library_symbol *, void *),
+ void *data)
+{
+ struct library *lib;
+ for (lib = start_after != NULL ? start_after->lib : proc->libraries;
+ lib != NULL; lib = lib->next) {
+ start_after = library_each_symbol(lib, start_after, cb, data);
+ if (start_after != NULL)
+ return start_after;
+ }
+
+ return NULL;
+}
+
+#define DEF_READER(NAME, SIZE) \
+ int \
+ NAME(struct process *proc, arch_addr_t addr, \
+ uint##SIZE##_t *lp) \
+ { \
+ union { \
+ uint##SIZE##_t dst; \
+ char buf[0]; \
+ } u; \
+ if (umovebytes(proc, addr, &u.buf, sizeof(u.dst)) \
+ != sizeof(u.dst)) \
+ return -1; \
+ *lp = u.dst; \
+ return 0; \
+ }
+
+DEF_READER(proc_read_8, 8)
+DEF_READER(proc_read_16, 16)
+DEF_READER(proc_read_32, 32)
+DEF_READER(proc_read_64, 64)
+
+#undef DEF_READER
projects / platform / upstream / ltrace.git / blobdiff