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-rw-r--r--app/core/gimpbacktrace-linux.c725
1 files changed, 725 insertions, 0 deletions
diff --git a/app/core/gimpbacktrace-linux.c b/app/core/gimpbacktrace-linux.c
new file mode 100644
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--- /dev/null
+++ b/app/core/gimpbacktrace-linux.c
@@ -0,0 +1,725 @@
+/* GIMP - The GNU Image Manipulation Program
+ * Copyright (C) 1995-1999 Spencer Kimball and Peter Mattis
+ *
+ * gimpbacktrace-linux.c
+ * Copyright (C) 2018 Ell
+ *
+ * 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 3 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, see <https://www.gnu.org/licenses/>.
+ */
+
+
+#define _GNU_SOURCE
+
+
+#include "config.h"
+
+#include <gio/gio.h>
+
+#include "gimpbacktrace-backend.h"
+
+
+#ifdef GIMP_BACKTRACE_BACKEND_LINUX
+
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <signal.h>
+#include <execinfo.h>
+#include <dlfcn.h>
+#include <string.h>
+#include <stdio.h>
+
+#ifdef HAVE_LIBBACKTRACE
+#include <backtrace.h>
+#endif
+
+#ifdef HAVE_LIBUNWIND
+#define UNW_LOCAL_ONLY
+#include <libunwind.h>
+#endif
+
+#include "core-types.h"
+
+#include "gimpbacktrace.h"
+
+
+#define MAX_N_THREADS 256
+#define MAX_N_FRAMES 256
+#define MAX_THREAD_NAME_SIZE 32
+#define N_SKIPPED_FRAMES 2
+#define MAX_WAIT_TIME (G_TIME_SPAN_SECOND / 20)
+#define BACKTRACE_SIGNAL SIGUSR1
+
+
+typedef struct _GimpBacktraceThread GimpBacktraceThread;
+
+
+struct _GimpBacktraceThread
+{
+ pid_t tid;
+ gchar name[MAX_THREAD_NAME_SIZE];
+ gchar state;
+
+ guintptr frames[MAX_N_FRAMES];
+ gint n_frames;
+};
+
+struct _GimpBacktrace
+{
+ GimpBacktraceThread *threads;
+ gint n_threads;
+};
+
+
+/* local function prototypes */
+
+static inline gint gimp_backtrace_normalize_frame (GimpBacktrace *backtrace,
+ gint thread,
+ gint frame);
+
+static gint gimp_backtrace_enumerate_threads (gboolean include_current_thread,
+ pid_t *threads,
+ gint size);
+static void gimp_backtrace_read_thread_name (pid_t tid,
+ gchar *name,
+ gint size);
+static gchar gimp_backtrace_read_thread_state (pid_t tid);
+
+static void gimp_backtrace_signal_handler (gint signum);
+
+
+/* static variables */
+
+static GMutex mutex;
+static gint n_initializations;
+static gboolean initialized;
+static struct sigaction orig_action;
+static pid_t blacklisted_threads[MAX_N_THREADS];
+static gint n_blacklisted_threads;
+static GimpBacktrace *handler_backtrace;
+static gint handler_n_remaining_threads;
+static gint handler_lock;
+
+#ifdef HAVE_LIBBACKTRACE
+static struct backtrace_state *backtrace_state;
+#endif
+
+static const gchar * const blacklisted_thread_names[] =
+{
+ "gmain",
+ "threaded-ml"
+};
+
+
+/* private functions */
+
+
+static inline gint
+gimp_backtrace_normalize_frame (GimpBacktrace *backtrace,
+ gint thread,
+ gint frame)
+{
+ if (frame >= 0)
+ return frame + N_SKIPPED_FRAMES;
+ else
+ return backtrace->threads[thread].n_frames + frame;
+}
+
+static gint
+gimp_backtrace_enumerate_threads (gboolean include_current_thread,
+ pid_t *threads,
+ gint size)
+{
+ DIR *dir;
+ struct dirent *dirent;
+ pid_t tid;
+ gint n_threads;
+
+ dir = opendir ("/proc/self/task");
+
+ if (! dir)
+ return 0;
+
+ tid = syscall (SYS_gettid);
+
+ n_threads = 0;
+
+ while (n_threads < size && (dirent = readdir (dir)))
+ {
+ pid_t id = g_ascii_strtoull (dirent->d_name, NULL, 10);
+
+ if (id)
+ {
+ if (! include_current_thread && id == tid)
+ id = 0;
+ }
+
+ if (id)
+ {
+ gint i;
+
+ for (i = 0; i < n_blacklisted_threads; i++)
+ {
+ if (id == blacklisted_threads[i])
+ {
+ id = 0;
+
+ break;
+ }
+ }
+ }
+
+ if (id)
+ threads[n_threads++] = id;
+ }
+
+ closedir (dir);
+
+ return n_threads;
+}
+
+static void
+gimp_backtrace_read_thread_name (pid_t tid,
+ gchar *name,
+ gint size)
+{
+ gchar filename[64];
+ gint fd;
+
+ if (size <= 0)
+ return;
+
+ name[0] = '\0';
+
+ g_snprintf (filename, sizeof (filename),
+ "/proc/self/task/%llu/comm",
+ (unsigned long long) tid);
+
+ fd = open (filename, O_RDONLY);
+
+ if (fd >= 0)
+ {
+ gint n = read (fd, name, size);
+
+ if (n > 0)
+ name[n - 1] = '\0';
+
+ close (fd);
+ }
+}
+
+static gchar
+gimp_backtrace_read_thread_state (pid_t tid)
+{
+ gchar buffer[64];
+ gint fd;
+ gchar state = '\0';
+
+ g_snprintf (buffer, sizeof (buffer),
+ "/proc/self/task/%llu/stat",
+ (unsigned long long) tid);
+
+ fd = open (buffer, O_RDONLY);
+
+ if (fd >= 0)
+ {
+ gint n = read (fd, buffer, sizeof (buffer));
+
+ if (n > 0)
+ buffer[n - 1] = '\0';
+
+ sscanf (buffer, "%*d %*s %c", &state);
+
+ close (fd);
+ }
+
+ return state;
+}
+
+static void
+gimp_backtrace_signal_handler (gint signum)
+{
+ GimpBacktrace *curr_backtrace;
+ gint lock;
+
+ do
+ {
+ lock = g_atomic_int_get (&handler_lock);
+
+ if (lock < 0)
+ continue;
+ }
+ while (! g_atomic_int_compare_and_exchange (&handler_lock, lock, lock + 1));
+
+ curr_backtrace = g_atomic_pointer_get (&handler_backtrace);
+
+ if (curr_backtrace)
+ {
+ pid_t tid = syscall (SYS_gettid);
+ gint i;
+
+ for (i = 0; i < curr_backtrace->n_threads; i++)
+ {
+ GimpBacktraceThread *thread = &curr_backtrace->threads[i];
+
+ if (thread->tid == tid)
+ {
+ thread->n_frames = backtrace ((gpointer *) thread->frames,
+ MAX_N_FRAMES);
+
+ g_atomic_int_dec_and_test (&handler_n_remaining_threads);
+
+ break;
+ }
+ }
+ }
+
+ g_atomic_int_dec_and_test (&handler_lock);
+}
+
+
+/* public functions */
+
+
+void
+gimp_backtrace_init (void)
+{
+#ifdef HAVE_LIBBACKTRACE
+ backtrace_state = backtrace_create_state (NULL, 0, NULL, NULL);
+#endif
+}
+
+gboolean
+gimp_backtrace_start (void)
+{
+ g_mutex_lock (&mutex);
+
+ if (n_initializations == 0)
+ {
+ struct sigaction action = {};
+
+ action.sa_handler = gimp_backtrace_signal_handler;
+ action.sa_flags = SA_RESTART;
+
+ sigemptyset (&action.sa_mask);
+
+ if (sigaction (BACKTRACE_SIGNAL, &action, &orig_action) == 0)
+ {
+ pid_t *threads;
+ gint n_threads;
+ gint i;
+
+ n_blacklisted_threads = 0;
+
+ threads = g_new (pid_t, MAX_N_THREADS);
+
+ n_threads = gimp_backtrace_enumerate_threads (TRUE,
+ threads, MAX_N_THREADS);
+
+ for (i = 0; i < n_threads; i++)
+ {
+ gchar name[MAX_THREAD_NAME_SIZE];
+ gint j;
+
+ gimp_backtrace_read_thread_name (threads[i],
+ name, MAX_THREAD_NAME_SIZE);
+
+ for (j = 0; j < G_N_ELEMENTS (blacklisted_thread_names); j++)
+ {
+ if (! strcmp (name, blacklisted_thread_names[j]))
+ {
+ blacklisted_threads[n_blacklisted_threads++] = threads[i];
+ }
+ }
+ }
+
+ g_free (threads);
+
+ initialized = TRUE;
+ }
+ }
+
+ n_initializations++;
+
+ g_mutex_unlock (&mutex);
+
+ return initialized;
+}
+
+void
+gimp_backtrace_stop (void)
+{
+ g_return_if_fail (n_initializations > 0);
+
+ g_mutex_lock (&mutex);
+
+ n_initializations--;
+
+ if (n_initializations == 0 && initialized)
+ {
+ if (sigaction (BACKTRACE_SIGNAL, &orig_action, NULL) < 0)
+ g_warning ("failed to restore origianl backtrace signal handler");
+
+ initialized = FALSE;
+ }
+
+ g_mutex_unlock (&mutex);
+}
+
+GimpBacktrace *
+gimp_backtrace_new (gboolean include_current_thread)
+{
+ GimpBacktrace *backtrace;
+ pid_t pid;
+ pid_t *threads;
+ gint n_threads;
+ gint64 start_time;
+ gint i;
+
+ if (! initialized)
+ return NULL;
+
+ pid = getpid ();
+
+ threads = g_new (pid_t, MAX_N_THREADS);
+
+ n_threads = gimp_backtrace_enumerate_threads (include_current_thread,
+ threads, MAX_N_THREADS);
+
+ if (n_threads == 0)
+ {
+ g_free (threads);
+
+ return NULL;
+ }
+
+ g_mutex_lock (&mutex);
+
+ backtrace = g_slice_new (GimpBacktrace);
+
+ backtrace->threads = g_new (GimpBacktraceThread, n_threads);
+ backtrace->n_threads = n_threads;
+
+ while (! g_atomic_int_compare_and_exchange (&handler_lock, 0, -1));
+
+ g_atomic_pointer_set (&handler_backtrace, backtrace);
+ g_atomic_int_set (&handler_n_remaining_threads, n_threads);
+
+ g_atomic_int_set (&handler_lock, 0);
+
+ for (i = 0; i < n_threads; i++)
+ {
+ GimpBacktraceThread *thread = &backtrace->threads[i];
+
+ thread->tid = threads[i];
+ thread->n_frames = 0;
+
+ gimp_backtrace_read_thread_name (thread->tid,
+ thread->name, MAX_THREAD_NAME_SIZE);
+
+ thread->state = gimp_backtrace_read_thread_state (thread->tid);
+
+ syscall (SYS_tgkill, pid, threads[i], BACKTRACE_SIGNAL);
+ }
+
+ g_free (threads);
+
+ start_time = g_get_monotonic_time ();
+
+ while (g_atomic_int_get (&handler_n_remaining_threads) > 0)
+ {
+ gint64 time = g_get_monotonic_time ();
+
+ if (time - start_time > MAX_WAIT_TIME)
+ break;
+
+ g_usleep (1000);
+ }
+
+ while (! g_atomic_int_compare_and_exchange (&handler_lock, 0, -1));
+
+ g_atomic_pointer_set (&handler_backtrace, NULL);
+
+ g_atomic_int_set (&handler_lock, 0);
+
+#if 0
+ if (handler_n_remaining_threads > 0)
+ {
+ gint j = 0;
+
+ for (i = 0; i < n_threads; i++)
+ {
+ if (backtrace->threads[i].n_frames == 0)
+ {
+ if (n_blacklisted_threads < MAX_N_THREADS)
+ {
+ blacklisted_threads[n_blacklisted_threads++] =
+ backtrace->threads[i].tid;
+ }
+ }
+ else
+ {
+ if (j < i)
+ backtrace->threads[j] = backtrace->threads[i];
+
+ j++;
+ }
+ }
+
+ n_threads = j;
+ }
+#endif
+
+ g_mutex_unlock (&mutex);
+
+ if (n_threads == 0)
+ {
+ gimp_backtrace_free (backtrace);
+
+ return NULL;
+ }
+
+ return backtrace;
+}
+
+void
+gimp_backtrace_free (GimpBacktrace *backtrace)
+{
+ if (! backtrace)
+ return;
+
+ g_free (backtrace->threads);
+
+ g_slice_free (GimpBacktrace, backtrace);
+}
+
+gint
+gimp_backtrace_get_n_threads (GimpBacktrace *backtrace)
+{
+ g_return_val_if_fail (backtrace != NULL, 0);
+
+ return backtrace->n_threads;
+}
+
+guintptr
+gimp_backtrace_get_thread_id (GimpBacktrace *backtrace,
+ gint thread)
+{
+ g_return_val_if_fail (backtrace != NULL, 0);
+ g_return_val_if_fail (thread >= 0 && thread < backtrace->n_threads, 0);
+
+ return backtrace->threads[thread].tid;
+}
+
+const gchar *
+gimp_backtrace_get_thread_name (GimpBacktrace *backtrace,
+ gint thread)
+{
+ g_return_val_if_fail (backtrace != NULL, NULL);
+ g_return_val_if_fail (thread >= 0 && thread < backtrace->n_threads, NULL);
+
+ if (backtrace->threads[thread].name[0])
+ return backtrace->threads[thread].name;
+ else
+ return NULL;
+}
+
+gboolean
+gimp_backtrace_is_thread_running (GimpBacktrace *backtrace,
+ gint thread)
+{
+ g_return_val_if_fail (backtrace != NULL, FALSE);
+ g_return_val_if_fail (thread >= 0 && thread < backtrace->n_threads, FALSE);
+
+ return backtrace->threads[thread].state == 'R';
+}
+
+gint
+gimp_backtrace_find_thread_by_id (GimpBacktrace *backtrace,
+ guintptr thread_id,
+ gint thread_hint)
+{
+ pid_t tid = thread_id;
+ gint i;
+
+ g_return_val_if_fail (backtrace != NULL, -1);
+
+ if (thread_hint >= 0 &&
+ thread_hint < backtrace->n_threads &&
+ backtrace->threads[thread_hint].tid == tid)
+ {
+ return thread_hint;
+ }
+
+ for (i = 0; i < backtrace->n_threads; i++)
+ {
+ if (backtrace->threads[i].tid == tid)
+ return i;
+ }
+
+ return -1;
+}
+
+gint
+gimp_backtrace_get_n_frames (GimpBacktrace *backtrace,
+ gint thread)
+{
+ g_return_val_if_fail (backtrace != NULL, 0);
+ g_return_val_if_fail (thread >= 0 && thread < backtrace->n_threads, 0);
+
+ return MAX (backtrace->threads[thread].n_frames - N_SKIPPED_FRAMES, 0);
+}
+
+guintptr
+gimp_backtrace_get_frame_address (GimpBacktrace *backtrace,
+ gint thread,
+ gint frame)
+{
+ g_return_val_if_fail (backtrace != NULL, 0);
+ g_return_val_if_fail (thread >= 0 && thread < backtrace->n_threads, 0);
+
+ frame = gimp_backtrace_normalize_frame (backtrace, thread, frame);
+
+ g_return_val_if_fail (frame >= N_SKIPPED_FRAMES &&
+ frame < backtrace->threads[thread].n_frames, 0);
+
+ return backtrace->threads[thread].frames[frame];
+}
+
+#ifdef HAVE_LIBBACKTRACE
+static void
+gimp_backtrace_syminfo_callback (GimpBacktraceAddressInfo *info,
+ guintptr pc,
+ const gchar *symname,
+ guintptr symval,
+ guintptr symsize)
+{
+ if (symname)
+ g_strlcpy (info->symbol_name, symname, sizeof (info->symbol_name));
+
+ info->symbol_address = symval;
+}
+
+static gint
+gimp_backtrace_pcinfo_callback (GimpBacktraceAddressInfo *info,
+ guintptr pc,
+ const gchar *filename,
+ gint lineno,
+ const gchar *function)
+{
+ if (function)
+ g_strlcpy (info->symbol_name, function, sizeof (info->symbol_name));
+
+ if (filename)
+ g_strlcpy (info->source_file, filename, sizeof (info->source_file));
+
+ info->source_line = lineno;
+
+ return 0;
+}
+#endif /* HAVE_LIBBACKTRACE */
+
+gboolean
+gimp_backtrace_get_address_info (guintptr address,
+ GimpBacktraceAddressInfo *info)
+{
+ Dl_info dl_info;
+ gboolean result = FALSE;
+
+ g_return_val_if_fail (info != NULL, FALSE);
+
+ info->object_name[0] = '\0';
+
+ info->symbol_name[0] = '\0';
+ info->symbol_address = 0;
+
+ info->source_file[0] = '\0';
+ info->source_line = 0;
+
+ if (dladdr ((gpointer) address, &dl_info))
+ {
+ if (dl_info.dli_fname)
+ {
+ g_strlcpy (info->object_name, dl_info.dli_fname,
+ sizeof (info->object_name));
+ }
+
+ if (dl_info.dli_sname)
+ {
+ g_strlcpy (info->symbol_name, dl_info.dli_sname,
+ sizeof (info->symbol_name));
+ }
+
+ info->symbol_address = (guintptr) dl_info.dli_saddr;
+
+ result = TRUE;
+ }
+
+#ifdef HAVE_LIBBACKTRACE
+ if (backtrace_state)
+ {
+ backtrace_syminfo (
+ backtrace_state, address,
+ (backtrace_syminfo_callback) gimp_backtrace_syminfo_callback,
+ NULL,
+ info);
+
+ backtrace_pcinfo (
+ backtrace_state, address,
+ (backtrace_full_callback) gimp_backtrace_pcinfo_callback,
+ NULL,
+ info);
+
+ result = TRUE;
+ }
+#endif /* HAVE_LIBBACKTRACE */
+
+#ifdef HAVE_LIBUNWIND
+/* we use libunwind to get the symbol name, when available, even if dladdr() or
+ * libbacktrace already found one, since it provides more descriptive names in
+ * some cases, and, in particular, full symbol names for C++ lambdas.
+ *
+ * note that, in some cases, this can result in a discrepancy between the
+ * symbol name, and the corresponding source location.
+ */
+#if 0
+ if (! info->symbol_name[0])
+#endif
+ {
+ unw_context_t context = {};
+ unw_cursor_t cursor;
+ unw_word_t offset;
+
+ if (unw_init_local (&cursor, &context) == 0 &&
+ unw_set_reg (&cursor, UNW_REG_IP, address) == 0 &&
+ unw_get_proc_name (&cursor,
+ info->symbol_name, sizeof (info->symbol_name),
+ &offset) == 0)
+ {
+ info->symbol_address = address - offset;
+
+ result = TRUE;
+ }
+ }
+#endif /* HAVE_LIBUNWIND */
+
+ return result;
+}
+
+
+#endif /* GIMP_BACKTRACE_BACKEND_LINUX */