Squashed 'third_party/elfutils/' content from commit 555e15e
Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libdwfl/dwfl_frame.c b/libdwfl/dwfl_frame.c
new file mode 100644
index 0000000..881f735
--- /dev/null
+++ b/libdwfl/dwfl_frame.c
@@ -0,0 +1,478 @@
+/* Get Dwarf Frame state for target PID or core file.
+ Copyright (C) 2013, 2014 Red Hat, Inc.
+ This file is part of elfutils.
+
+ This file is free software; you can redistribute it and/or modify
+ it under the terms of either
+
+ * the GNU Lesser General Public License as published by the Free
+ Software Foundation; either version 3 of the License, or (at
+ your option) any later version
+
+ or
+
+ * 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
+
+ or both in parallel, as here.
+
+ elfutils 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 copies of the GNU General Public License and
+ the GNU Lesser General Public License along with this program. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include "libdwflP.h"
+#include <unistd.h>
+
+/* Set STATE->pc_set from STATE->regs according to the backend. Return true on
+ success, false on error. */
+static bool
+state_fetch_pc (Dwfl_Frame *state)
+{
+ switch (state->pc_state)
+ {
+ case DWFL_FRAME_STATE_PC_SET:
+ return true;
+ case DWFL_FRAME_STATE_PC_UNDEFINED:
+ abort ();
+ case DWFL_FRAME_STATE_ERROR:
+ {
+ Ebl *ebl = state->thread->process->ebl;
+ Dwarf_CIE abi_info;
+ if (ebl_abi_cfi (ebl, &abi_info) != 0)
+ {
+ __libdwfl_seterrno (DWFL_E_LIBEBL);
+ return false;
+ }
+ unsigned ra = abi_info.return_address_register;
+ /* dwarf_frame_state_reg_is_set is not applied here. */
+ if (ra >= ebl_frame_nregs (ebl))
+ {
+ __libdwfl_seterrno (DWFL_E_LIBEBL_BAD);
+ return false;
+ }
+ state->pc = state->regs[ra] + ebl_ra_offset (ebl);
+ state->pc_state = DWFL_FRAME_STATE_PC_SET;
+ }
+ return true;
+ }
+ abort ();
+}
+
+/* Do not call it on your own, to be used by thread_* functions only. */
+
+static void
+state_free (Dwfl_Frame *state)
+{
+ Dwfl_Thread *thread = state->thread;
+ assert (thread->unwound == state);
+ thread->unwound = state->unwound;
+ free (state);
+}
+
+static void
+thread_free_all_states (Dwfl_Thread *thread)
+{
+ while (thread->unwound)
+ state_free (thread->unwound);
+}
+
+static Dwfl_Frame *
+state_alloc (Dwfl_Thread *thread)
+{
+ assert (thread->unwound == NULL);
+ Ebl *ebl = thread->process->ebl;
+ size_t nregs = ebl_frame_nregs (ebl);
+ if (nregs == 0)
+ return NULL;
+ assert (nregs < sizeof (((Dwfl_Frame *) NULL)->regs_set) * 8);
+ Dwfl_Frame *state = malloc (sizeof (*state) + sizeof (*state->regs) * nregs);
+ if (state == NULL)
+ return NULL;
+ state->thread = thread;
+ state->signal_frame = false;
+ state->initial_frame = true;
+ state->pc_state = DWFL_FRAME_STATE_ERROR;
+ memset (state->regs_set, 0, sizeof (state->regs_set));
+ thread->unwound = state;
+ state->unwound = NULL;
+ return state;
+}
+
+void
+internal_function
+__libdwfl_process_free (Dwfl_Process *process)
+{
+ Dwfl *dwfl = process->dwfl;
+ if (process->callbacks->detach != NULL)
+ process->callbacks->detach (dwfl, process->callbacks_arg);
+ assert (dwfl->process == process);
+ dwfl->process = NULL;
+ if (process->ebl_close)
+ ebl_closebackend (process->ebl);
+ free (process);
+ dwfl->attacherr = DWFL_E_NOERROR;
+}
+
+/* Allocate new Dwfl_Process for DWFL. */
+static void
+process_alloc (Dwfl *dwfl)
+{
+ Dwfl_Process *process = malloc (sizeof (*process));
+ if (process == NULL)
+ return;
+ process->dwfl = dwfl;
+ dwfl->process = process;
+}
+
+bool
+dwfl_attach_state (Dwfl *dwfl, Elf *elf, pid_t pid,
+ const Dwfl_Thread_Callbacks *thread_callbacks, void *arg)
+{
+ if (dwfl->process != NULL)
+ {
+ __libdwfl_seterrno (DWFL_E_ATTACH_STATE_CONFLICT);
+ return false;
+ }
+
+ /* Reset any previous error, we are just going to try again. */
+ dwfl->attacherr = DWFL_E_NOERROR;
+ /* thread_callbacks is declared NN */
+ if (thread_callbacks->next_thread == NULL
+ || thread_callbacks->set_initial_registers == NULL)
+ {
+ dwfl->attacherr = DWFL_E_INVALID_ARGUMENT;
+ fail:
+ dwfl->attacherr = __libdwfl_canon_error (dwfl->attacherr);
+ __libdwfl_seterrno (dwfl->attacherr);
+ return false;
+ }
+
+ Ebl *ebl;
+ bool ebl_close;
+ if (elf != NULL)
+ {
+ ebl = ebl_openbackend (elf);
+ ebl_close = true;
+ }
+ else
+ {
+ ebl = NULL;
+ for (Dwfl_Module *mod = dwfl->modulelist; mod != NULL; mod = mod->next)
+ {
+ /* Reading of the vDSO or (deleted) modules may fail as
+ /proc/PID/mem is unreadable without PTRACE_ATTACH and
+ we may not be PTRACE_ATTACH-ed now. MOD would not be
+ re-read later to unwind it when we are already
+ PTRACE_ATTACH-ed to PID. This happens when this function
+ is called from dwfl_linux_proc_attach with elf == NULL.
+ __libdwfl_module_getebl will call __libdwfl_getelf which
+ will call the find_elf callback. */
+ if (strncmp (mod->name, "[vdso: ", 7) == 0
+ || strcmp (strrchr (mod->name, ' ') ?: "",
+ " (deleted)") == 0)
+ continue;
+ Dwfl_Error error = __libdwfl_module_getebl (mod);
+ if (error != DWFL_E_NOERROR)
+ continue;
+ ebl = mod->ebl;
+ break;
+ }
+ ebl_close = false;
+ }
+ if (ebl == NULL)
+ {
+ /* Not identified EBL from any of the modules. */
+ dwfl->attacherr = DWFL_E_PROCESS_NO_ARCH;
+ goto fail;
+ }
+ process_alloc (dwfl);
+ Dwfl_Process *process = dwfl->process;
+ if (process == NULL)
+ {
+ if (ebl_close)
+ ebl_closebackend (ebl);
+ dwfl->attacherr = DWFL_E_NOMEM;
+ goto fail;
+ }
+ process->ebl = ebl;
+ process->ebl_close = ebl_close;
+ process->pid = pid;
+ process->callbacks = thread_callbacks;
+ process->callbacks_arg = arg;
+ return true;
+}
+INTDEF(dwfl_attach_state)
+
+pid_t
+dwfl_pid (Dwfl *dwfl)
+{
+ if (dwfl->attacherr != DWFL_E_NOERROR)
+ {
+ __libdwfl_seterrno (dwfl->attacherr);
+ return -1;
+ }
+
+ if (dwfl->process == NULL)
+ {
+ __libdwfl_seterrno (DWFL_E_NO_ATTACH_STATE);
+ return -1;
+ }
+ return dwfl->process->pid;
+}
+INTDEF(dwfl_pid)
+
+Dwfl *
+dwfl_thread_dwfl (Dwfl_Thread *thread)
+{
+ return thread->process->dwfl;
+}
+INTDEF(dwfl_thread_dwfl)
+
+pid_t
+dwfl_thread_tid (Dwfl_Thread *thread)
+{
+ return thread->tid;
+}
+INTDEF(dwfl_thread_tid)
+
+Dwfl_Thread *
+dwfl_frame_thread (Dwfl_Frame *state)
+{
+ return state->thread;
+}
+INTDEF(dwfl_frame_thread)
+
+int
+dwfl_getthreads (Dwfl *dwfl, int (*callback) (Dwfl_Thread *thread, void *arg),
+ void *arg)
+{
+ if (dwfl->attacherr != DWFL_E_NOERROR)
+ {
+ __libdwfl_seterrno (dwfl->attacherr);
+ return -1;
+ }
+
+ Dwfl_Process *process = dwfl->process;
+ if (process == NULL)
+ {
+ __libdwfl_seterrno (DWFL_E_NO_ATTACH_STATE);
+ return -1;
+ }
+
+ Dwfl_Thread thread;
+ thread.process = process;
+ thread.unwound = NULL;
+ thread.callbacks_arg = NULL;
+ for (;;)
+ {
+ thread.tid = process->callbacks->next_thread (dwfl,
+ process->callbacks_arg,
+ &thread.callbacks_arg);
+ if (thread.tid < 0)
+ {
+ Dwfl_Error saved_errno = dwfl_errno ();
+ thread_free_all_states (&thread);
+ __libdwfl_seterrno (saved_errno);
+ return -1;
+ }
+ if (thread.tid == 0)
+ {
+ thread_free_all_states (&thread);
+ __libdwfl_seterrno (DWFL_E_NOERROR);
+ return 0;
+ }
+ int err = callback (&thread, arg);
+ if (err != DWARF_CB_OK)
+ {
+ thread_free_all_states (&thread);
+ return err;
+ }
+ assert (thread.unwound == NULL);
+ }
+ /* NOTREACHED */
+}
+INTDEF(dwfl_getthreads)
+
+struct one_arg
+{
+ pid_t tid;
+ bool seen;
+ int (*callback) (Dwfl_Thread *thread, void *arg);
+ void *arg;
+ int ret;
+};
+
+static int
+get_one_thread_cb (Dwfl_Thread *thread, void *arg)
+{
+ struct one_arg *oa = (struct one_arg *) arg;
+ if (! oa->seen && INTUSE(dwfl_thread_tid) (thread) == oa->tid)
+ {
+ oa->seen = true;
+ oa->ret = oa->callback (thread, oa->arg);
+ return DWARF_CB_ABORT;
+ }
+
+ return DWARF_CB_OK;
+}
+
+/* Note not currently exported, will be when there are more Dwfl_Thread
+ properties to query. Use dwfl_getthread_frames for now directly. */
+static int
+getthread (Dwfl *dwfl, pid_t tid,
+ int (*callback) (Dwfl_Thread *thread, void *arg),
+ void *arg)
+{
+ if (dwfl->attacherr != DWFL_E_NOERROR)
+ {
+ __libdwfl_seterrno (dwfl->attacherr);
+ return -1;
+ }
+
+ Dwfl_Process *process = dwfl->process;
+ if (process == NULL)
+ {
+ __libdwfl_seterrno (DWFL_E_NO_ATTACH_STATE);
+ return -1;
+ }
+
+ if (process->callbacks->get_thread != NULL)
+ {
+ Dwfl_Thread thread;
+ thread.process = process;
+ thread.unwound = NULL;
+ thread.callbacks_arg = NULL;
+
+ if (process->callbacks->get_thread (dwfl, tid, process->callbacks_arg,
+ &thread.callbacks_arg))
+ {
+ int err;
+ thread.tid = tid;
+ err = callback (&thread, arg);
+ thread_free_all_states (&thread);
+ return err;
+ }
+
+ return -1;
+ }
+
+ struct one_arg oa = { .tid = tid, .callback = callback,
+ .arg = arg, .seen = false };
+ int err = INTUSE(dwfl_getthreads) (dwfl, get_one_thread_cb, &oa);
+
+ if (err == DWARF_CB_ABORT && oa.seen)
+ return oa.ret;
+
+ if (err == DWARF_CB_OK && ! oa.seen)
+ {
+ errno = ESRCH;
+ __libdwfl_seterrno (DWFL_E_ERRNO);
+ return -1;
+ }
+
+ return err;
+}
+
+struct one_thread
+{
+ int (*callback) (Dwfl_Frame *frame, void *arg);
+ void *arg;
+};
+
+static int
+get_one_thread_frames_cb (Dwfl_Thread *thread, void *arg)
+{
+ struct one_thread *ot = (struct one_thread *) arg;
+ return INTUSE(dwfl_thread_getframes) (thread, ot->callback, ot->arg);
+}
+
+int
+dwfl_getthread_frames (Dwfl *dwfl, pid_t tid,
+ int (*callback) (Dwfl_Frame *frame, void *arg),
+ void *arg)
+{
+ struct one_thread ot = { .callback = callback, .arg = arg };
+ return getthread (dwfl, tid, get_one_thread_frames_cb, &ot);
+}
+INTDEF(dwfl_getthread_frames)
+
+int
+dwfl_thread_getframes (Dwfl_Thread *thread,
+ int (*callback) (Dwfl_Frame *state, void *arg),
+ void *arg)
+{
+ if (thread->unwound != NULL)
+ {
+ /* We had to be called from inside CALLBACK. */
+ __libdwfl_seterrno (DWFL_E_ATTACH_STATE_CONFLICT);
+ return -1;
+ }
+ Ebl *ebl = thread->process->ebl;
+ if (ebl_frame_nregs (ebl) == 0)
+ {
+ __libdwfl_seterrno (DWFL_E_NO_UNWIND);
+ return -1;
+ }
+ if (state_alloc (thread) == NULL)
+ {
+ __libdwfl_seterrno (DWFL_E_NOMEM);
+ return -1;
+ }
+ Dwfl_Process *process = thread->process;
+ if (! process->callbacks->set_initial_registers (thread,
+ thread->callbacks_arg))
+ {
+ thread_free_all_states (thread);
+ return -1;
+ }
+ if (! state_fetch_pc (thread->unwound))
+ {
+ if (process->callbacks->thread_detach)
+ process->callbacks->thread_detach (thread, thread->callbacks_arg);
+ thread_free_all_states (thread);
+ return -1;
+ }
+
+ Dwfl_Frame *state;
+ do
+ {
+ state = thread->unwound;
+ int err = callback (state, arg);
+ if (err != DWARF_CB_OK)
+ {
+ if (process->callbacks->thread_detach)
+ process->callbacks->thread_detach (thread, thread->callbacks_arg);
+ thread_free_all_states (thread);
+ return err;
+ }
+ __libdwfl_frame_unwind (state);
+ /* The old frame is no longer needed. */
+ state_free (thread->unwound);
+ state = thread->unwound;
+ }
+ while (state && state->pc_state == DWFL_FRAME_STATE_PC_SET);
+
+ Dwfl_Error err = dwfl_errno ();
+ if (process->callbacks->thread_detach)
+ process->callbacks->thread_detach (thread, thread->callbacks_arg);
+ if (state == NULL || state->pc_state == DWFL_FRAME_STATE_ERROR)
+ {
+ thread_free_all_states (thread);
+ __libdwfl_seterrno (err);
+ return -1;
+ }
+ assert (state->pc_state == DWFL_FRAME_STATE_PC_UNDEFINED);
+ thread_free_all_states (thread);
+ return 0;
+}
+INTDEF(dwfl_thread_getframes)