Adding upstream version 2.6.12.upstream/2.6.12upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1467 insertions, 0 deletions

diff --git a/src/debug.c b/src/debug.c
new file mode 100644
index 0000000..6d510e9
--- /dev/null
+++ b/src/debug.c
@@ -0,0 +1,1467 @@
+/*
+ * Process debugging functions.
+ *
+ * Copyright 2000-2019 Willy Tarreau <willy@haproxy.org>.
+ *
+ * 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.
+ *
+ */
+
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <syslog.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#ifdef USE_EPOLL
+#include <sys/epoll.h>
+#endif
+
+#include <haproxy/api.h>
+#include <haproxy/applet.h>
+#include <haproxy/buf.h>
+#include <haproxy/cli.h>
+#include <haproxy/clock.h>
+#include <haproxy/debug.h>
+#include <haproxy/fd.h>
+#include <haproxy/global.h>
+#include <haproxy/hlua.h>
+#include <haproxy/http_ana.h>
+#include <haproxy/log.h>
+#include <haproxy/net_helper.h>
+#include <haproxy/sc_strm.h>
+#include <haproxy/stconn.h>
+#include <haproxy/task.h>
+#include <haproxy/thread.h>
+#include <haproxy/time.h>
+#include <haproxy/tools.h>
+#include <import/ist.h>
+
+
+/* mask of threads still having to dump, used to respect ordering. Only used
+ * when USE_THREAD_DUMP is set.
+ */
+volatile unsigned long threads_to_dump = 0;
+unsigned int panic_started = 0;
+unsigned int debug_commands_issued = 0;
+
+/* dumps a backtrace of the current thread that is appended to buffer <buf>.
+ * Lines are prefixed with the string <prefix> which may be empty (used for
+ * indenting). It is recommended to use this at a function's tail so that
+ * the function does not appear in the call stack. The <dump> argument
+ * indicates what dump state to start from, and should usually be zero. It
+ * may be among the following values:
+ *   - 0: search usual callers before step 1, or directly jump to 2
+ *   - 1: skip usual callers before step 2
+ *   - 2: dump until polling loop, scheduler, or main() (excluded)
+ *   - 3: end
+ *   - 4-7: like 0 but stops *after* main.
+ */
+void ha_dump_backtrace(struct buffer *buf, const char *prefix, int dump)
+{
+	struct buffer bak;
+	char pfx2[100];
+	void *callers[100];
+	int j, nptrs;
+	const void *addr;
+
+	nptrs = my_backtrace(callers, sizeof(callers)/sizeof(*callers));
+	if (!nptrs)
+		return;
+
+	if (snprintf(pfx2, sizeof(pfx2), "%s| ", prefix) > sizeof(pfx2))
+		pfx2[0] = 0;
+
+	/* The call backtrace_symbols_fd(callers, nptrs, STDOUT_FILENO would
+	 * produce similar output to the following:
+	 */
+	chunk_appendf(buf, "%scall trace(%d):\n", prefix, nptrs);
+	for (j = 0; (j < nptrs || (dump & 3) < 2); j++) {
+		if (j == nptrs && !(dump & 3)) {
+			/* we failed to spot the starting point of the
+			 * dump, let's start over dumping everything we
+			 * have.
+			 */
+			dump += 2;
+			j = 0;
+		}
+		bak = *buf;
+		dump_addr_and_bytes(buf, pfx2, callers[j], 8);
+		addr = resolve_sym_name(buf, ": ", callers[j]);
+		if ((dump & 3) == 0) {
+			/* dump not started, will start *after*
+			 * ha_thread_dump_all_to_trash, ha_panic and ha_backtrace_to_stderr
+			 */
+			if (addr == ha_thread_dump_all_to_trash || addr == ha_panic ||
+			    addr == ha_backtrace_to_stderr)
+				dump++;
+			*buf = bak;
+			continue;
+		}
+
+		if ((dump & 3) == 1) {
+			/* starting */
+			if (addr == ha_thread_dump_all_to_trash || addr == ha_panic ||
+			    addr == ha_backtrace_to_stderr) {
+				*buf = bak;
+				continue;
+			}
+			dump++;
+		}
+
+		if ((dump & 3) == 2) {
+			/* still dumping */
+			if (dump == 6) {
+				/* we only stop *after* main and we must send the LF */
+				if (addr == main) {
+					j = nptrs;
+					dump++;
+				}
+			}
+			else if (addr == run_poll_loop || addr == main || addr == run_tasks_from_lists) {
+				dump++;
+				*buf = bak;
+				break;
+			}
+		}
+		/* OK, line dumped */
+		chunk_appendf(buf, "\n");
+	}
+}
+
+/* dump a backtrace of current thread's stack to stderr. */
+void ha_backtrace_to_stderr(void)
+{
+	char area[2048];
+	struct buffer b = b_make(area, sizeof(area), 0, 0);
+
+	ha_dump_backtrace(&b, "  ", 4);
+	if (b.data)
+		DISGUISE(write(2, b.area, b.data));
+}
+
+/* Dumps to the buffer some known information for the desired thread, and
+ * optionally extra info for the current thread. The dump will be appended to
+ * the buffer, so the caller is responsible for preliminary initializing it.
+ * The calling thread ID needs to be passed in <calling_tid> to display a star
+ * in front of the calling thread's line (usually it's tid). Any stuck thread
+ * is also prefixed with a '>'.
+ */
+void ha_thread_dump(struct buffer *buf, int thr, int calling_tid)
+{
+	unsigned long thr_bit = 1UL << thr;
+	unsigned long long p = ha_thread_ctx[thr].prev_cpu_time;
+	unsigned long long n = now_cpu_time_thread(thr);
+	int stuck = !!(ha_thread_ctx[thr].flags & TH_FL_STUCK);
+
+	chunk_appendf(buf,
+	              "%c%cThread %-2u: id=0x%llx act=%d glob=%d wq=%d rq=%d tl=%d tlsz=%d rqsz=%d\n"
+	              "     %2u/%-2u   stuck=%d prof=%d",
+	              (thr == calling_tid) ? '*' : ' ', stuck ? '>' : ' ', thr + 1,
+		      ha_get_pthread_id(thr),
+		      thread_has_tasks(),
+	              !!(global_tasks_mask & thr_bit),
+	              !eb_is_empty(&ha_thread_ctx[thr].timers),
+	              !eb_is_empty(&ha_thread_ctx[thr].rqueue),
+	              !(LIST_ISEMPTY(&ha_thread_ctx[thr].tasklets[TL_URGENT]) &&
+			LIST_ISEMPTY(&ha_thread_ctx[thr].tasklets[TL_NORMAL]) &&
+			LIST_ISEMPTY(&ha_thread_ctx[thr].tasklets[TL_BULK]) &&
+			MT_LIST_ISEMPTY(&ha_thread_ctx[thr].shared_tasklet_list)),
+	              ha_thread_ctx[thr].tasks_in_list,
+	              ha_thread_ctx[thr].rq_total,
+		      ha_thread_info[thr].tg->tgid, ha_thread_info[thr].ltid + 1,
+	              stuck,
+	              !!(task_profiling_mask & thr_bit));
+
+	chunk_appendf(buf,
+	              " harmless=%d wantrdv=%d",
+	              !!(threads_harmless_mask & thr_bit),
+	              !!(threads_want_rdv_mask & thr_bit));
+
+	chunk_appendf(buf, "\n");
+	chunk_appendf(buf, "             cpu_ns: poll=%llu now=%llu diff=%llu\n", p, n, n-p);
+
+	/* this is the end of what we can dump from outside the current thread */
+
+	if (thr != tid)
+		return;
+
+	chunk_appendf(buf, "             curr_task=");
+	ha_task_dump(buf, th_ctx->current, "             ");
+
+	if (stuck) {
+		/* We only emit the backtrace for stuck threads in order not to
+		 * waste precious output buffer space with non-interesting data.
+		 * Please leave this as the last instruction in this function
+		 * so that the compiler uses tail merging and the current
+		 * function does not appear in the stack.
+		 */
+		ha_dump_backtrace(buf, "             ", 0);
+	}
+}
+
+
+/* dumps into the buffer some information related to task <task> (which may
+ * either be a task or a tasklet, and prepend each line except the first one
+ * with <pfx>. The buffer is only appended and the first output starts by the
+ * pointer itself. The caller is responsible for making sure the task is not
+ * going to vanish during the dump.
+ */
+void ha_task_dump(struct buffer *buf, const struct task *task, const char *pfx)
+{
+	const struct stream *s = NULL;
+	const struct appctx __maybe_unused *appctx = NULL;
+	struct hlua __maybe_unused *hlua = NULL;
+	const struct stconn *sc;
+
+	if (!task) {
+		chunk_appendf(buf, "0\n");
+		return;
+	}
+
+	if (TASK_IS_TASKLET(task))
+		chunk_appendf(buf,
+		              "%p (tasklet) calls=%u\n",
+		              task,
+		              task->calls);
+	else
+		chunk_appendf(buf,
+		              "%p (task) calls=%u last=%llu%s\n",
+		              task,
+		              task->calls,
+		              task->wake_date ? (unsigned long long)(now_mono_time() - task->wake_date) : 0,
+		              task->wake_date ? " ns ago" : "");
+
+	chunk_appendf(buf, "%s  fct=%p(", pfx, task->process);
+	resolve_sym_name(buf, NULL, task->process);
+	chunk_appendf(buf,") ctx=%p", task->context);
+
+	if (task->process == task_run_applet && (appctx = task->context))
+		chunk_appendf(buf, "(%s)\n", appctx->applet->name);
+	else
+		chunk_appendf(buf, "\n");
+
+	if (task->process == process_stream && task->context)
+		s = (struct stream *)task->context;
+	else if (task->process == task_run_applet && task->context && (sc = appctx_sc((struct appctx *)task->context)))
+		s = sc_strm(sc);
+	else if (task->process == sc_conn_io_cb && task->context)
+		s = sc_strm(((struct stconn *)task->context));
+
+	if (s)
+		stream_dump(buf, s, pfx, '\n');
+
+#ifdef USE_LUA
+	hlua = NULL;
+	if (s && (hlua = s->hlua)) {
+		chunk_appendf(buf, "%sCurrent executing Lua from a stream analyser -- ", pfx);
+	}
+	else if (task->process == hlua_process_task && (hlua = task->context)) {
+		chunk_appendf(buf, "%sCurrent executing a Lua task -- ", pfx);
+	}
+	else if (task->process == task_run_applet && (appctx = task->context) &&
+		 (appctx->applet->fct == hlua_applet_tcp_fct)) {
+		chunk_appendf(buf, "%sCurrent executing a Lua TCP service -- ", pfx);
+	}
+	else if (task->process == task_run_applet && (appctx = task->context) &&
+		 (appctx->applet->fct == hlua_applet_http_fct)) {
+		chunk_appendf(buf, "%sCurrent executing a Lua HTTP service -- ", pfx);
+	}
+
+	if (hlua && hlua->T) {
+		chunk_appendf(buf, "stack traceback:\n    ");
+		append_prefixed_str(buf, hlua_traceback(hlua->T, "\n    "), pfx, '\n', 0);
+		b_putchr(buf, '\n');
+	}
+	else
+		b_putchr(buf, '\n');
+#endif
+}
+
+/* This function dumps all profiling settings. It returns 0 if the output
+ * buffer is full and it needs to be called again, otherwise non-zero.
+ */
+static int cli_io_handler_show_threads(struct appctx *appctx)
+{
+	struct stconn *sc = appctx_sc(appctx);
+	int thr;
+
+	if (unlikely(sc_ic(sc)->flags & (CF_WRITE_ERROR|CF_SHUTW)))
+		return 1;
+
+	if (appctx->st0)
+		thr = appctx->st1;
+	else
+		thr = 0;
+
+	chunk_reset(&trash);
+	ha_thread_dump_all_to_trash();
+
+	if (applet_putchk(appctx, &trash) == -1) {
+		/* failed, try again */
+		appctx->st1 = thr;
+		return 0;
+	}
+	return 1;
+}
+
+#if defined(HA_HAVE_DUMP_LIBS)
+/* parse a "show libs" command. It returns 1 if it emits anything otherwise zero. */
+static int debug_parse_cli_show_libs(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	if (!cli_has_level(appctx, ACCESS_LVL_OPER))
+		return 1;
+
+	chunk_reset(&trash);
+	if (dump_libs(&trash, 1))
+		return cli_msg(appctx, LOG_INFO, trash.area);
+	else
+		return 0;
+}
+#endif
+
+/* dumps a state of all threads into the trash and on fd #2, then aborts. */
+void ha_panic()
+{
+	if (HA_ATOMIC_FETCH_ADD(&panic_started, 1) != 0) {
+		/* a panic dump is already in progress, let's not disturb it,
+		 * we'll be called via signal DEBUGSIG. By returning we may be
+		 * able to leave a current signal handler (e.g. WDT) so that
+		 * this will ensure more reliable signal delivery.
+		 */
+		return;
+	}
+	chunk_reset(&trash);
+	chunk_appendf(&trash, "Thread %u is about to kill the process.\n", tid + 1);
+	ha_thread_dump_all_to_trash();
+	DISGUISE(write(2, trash.area, trash.data));
+	for (;;)
+		abort();
+}
+
+/* Complain with message <msg> on stderr. If <counter> is not NULL, it is
+ * atomically incremented, and the message is only printed when the counter
+ * was zero, so that the message is only printed once. <taint> is only checked
+ * on bit 1, and will taint the process either for a bug (2) or warn (0).
+ */
+void complain(int *counter, const char *msg, int taint)
+{
+	if (counter && _HA_ATOMIC_FETCH_ADD(counter, 1))
+		return;
+	DISGUISE(write(2, msg, strlen(msg)));
+	if (taint & 2)
+		mark_tainted(TAINTED_BUG);
+	else
+		mark_tainted(TAINTED_WARN);
+}
+
+/* parse a "debug dev exit" command. It always returns 1, though it should never return. */
+static int debug_parse_cli_exit(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	int code = atoi(args[3]);
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	exit(code);
+	return 1;
+}
+
+/* parse a "debug dev bug" command. It always returns 1, though it should never return.
+ * Note: we make sure not to make the function static so that it appears in the trace.
+ */
+int debug_parse_cli_bug(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	BUG_ON(one > zero);
+	return 1;
+}
+
+/* parse a "debug dev warn" command. It always returns 1.
+ * Note: we make sure not to make the function static so that it appears in the trace.
+ */
+int debug_parse_cli_warn(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	WARN_ON(one > zero);
+	return 1;
+}
+
+/* parse a "debug dev check" command. It always returns 1.
+ * Note: we make sure not to make the function static so that it appears in the trace.
+ */
+int debug_parse_cli_check(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	CHECK_IF(one > zero);
+	return 1;
+}
+
+/* parse a "debug dev close" command. It always returns 1. */
+static int debug_parse_cli_close(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	int fd;
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	if (!*args[3])
+		return cli_err(appctx, "Missing file descriptor number.\n");
+
+	fd = atoi(args[3]);
+	if (fd < 0 || fd >= global.maxsock)
+		return cli_err(appctx, "File descriptor out of range.\n");
+
+	if (!fdtab[fd].owner)
+		return cli_msg(appctx, LOG_INFO, "File descriptor was already closed.\n");
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	fd_delete(fd);
+	return 1;
+}
+
+/* parse a "debug dev delay" command. It always returns 1. */
+static int debug_parse_cli_delay(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	int delay = atoi(args[3]);
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	usleep((long)delay * 1000);
+	return 1;
+}
+
+/* parse a "debug dev log" command. It always returns 1. */
+static int debug_parse_cli_log(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	int arg;
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	chunk_reset(&trash);
+	for (arg = 3; *args[arg]; arg++) {
+		if (arg > 3)
+			chunk_strcat(&trash, " ");
+		chunk_strcat(&trash, args[arg]);
+	}
+
+	send_log(NULL, LOG_INFO, "%s\n", trash.area);
+	return 1;
+}
+
+/* parse a "debug dev loop" command. It always returns 1. */
+static int debug_parse_cli_loop(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	struct timeval deadline, curr;
+	int loop = atoi(args[3]);
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	gettimeofday(&curr, NULL);
+	tv_ms_add(&deadline, &curr, loop);
+
+	while (tv_ms_cmp(&curr, &deadline) < 0)
+		gettimeofday(&curr, NULL);
+
+	return 1;
+}
+
+/* parse a "debug dev panic" command. It always returns 1, though it should never return. */
+static int debug_parse_cli_panic(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	ha_panic();
+	return 1;
+}
+
+/* parse a "debug dev exec" command. It always returns 1. */
+#if defined(DEBUG_DEV)
+static int debug_parse_cli_exec(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	int pipefd[2];
+	int arg;
+	int pid;
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	chunk_reset(&trash);
+	for (arg = 3; *args[arg]; arg++) {
+		if (arg > 3)
+			chunk_strcat(&trash, " ");
+		chunk_strcat(&trash, args[arg]);
+	}
+
+	thread_isolate();
+	if (pipe(pipefd) < 0)
+		goto fail_pipe;
+
+	if (fd_set_cloexec(pipefd[0]) == -1)
+		goto fail_fcntl;
+
+	if (fd_set_cloexec(pipefd[1]) == -1)
+		goto fail_fcntl;
+
+	pid = fork();
+
+	if (pid < 0)
+		goto fail_fork;
+	else if (pid == 0) {
+		/* child */
+		char *cmd[4] = { "/bin/sh", "-c", 0, 0 };
+
+		close(0);
+		dup2(pipefd[1], 1);
+		dup2(pipefd[1], 2);
+
+		cmd[2] = trash.area;
+		execvp(cmd[0], cmd);
+		printf("execvp() failed\n");
+		exit(1);
+	}
+
+	/* parent */
+	thread_release();
+	close(pipefd[1]);
+	chunk_reset(&trash);
+	while (1) {
+		size_t ret = read(pipefd[0], trash.area + trash.data, trash.size - 20 - trash.data);
+		if (ret <= 0)
+			break;
+		trash.data += ret;
+		if (trash.data + 20 == trash.size) {
+			chunk_strcat(&trash, "\n[[[TRUNCATED]]]\n");
+			break;
+		}
+	}
+	close(pipefd[0]);
+	waitpid(pid, NULL, WNOHANG);
+	trash.area[trash.data] = 0;
+	return cli_msg(appctx, LOG_INFO, trash.area);
+
+ fail_fork:
+ fail_fcntl:
+	close(pipefd[0]);
+	close(pipefd[1]);
+ fail_pipe:
+	thread_release();
+	return cli_err(appctx, "Failed to execute command.\n");
+}
+#endif
+
+/* parse a "debug dev hex" command. It always returns 1. */
+static int debug_parse_cli_hex(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	unsigned long start, len;
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	if (!*args[3])
+		return cli_err(appctx, "Missing memory address to dump from.\n");
+
+	start = strtoul(args[3], NULL, 0);
+	if (!start)
+		return cli_err(appctx, "Will not dump from NULL address.\n");
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+
+	/* by default, dump ~128 till next block of 16 */
+	len = strtoul(args[4], NULL, 0);
+	if (!len)
+		len = ((start + 128) & -16) - start;
+
+	chunk_reset(&trash);
+	dump_hex(&trash, "  ", (const void *)start, len, 1);
+	trash.area[trash.data] = 0;
+	return cli_msg(appctx, LOG_INFO, trash.area);
+}
+
+/* parse a "debug dev sym <addr>" command. It always returns 1. */
+static int debug_parse_cli_sym(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	unsigned long addr;
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	if (!*args[3])
+		return cli_err(appctx, "Missing memory address to be resolved.\n");
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+
+	addr = strtoul(args[3], NULL, 0);
+	chunk_printf(&trash, "%#lx resolves to ", addr);
+	resolve_sym_name(&trash, NULL, (const void *)addr);
+	chunk_appendf(&trash, "\n");
+
+	return cli_msg(appctx, LOG_INFO, trash.area);
+}
+
+/* parse a "debug dev tkill" command. It always returns 1. */
+static int debug_parse_cli_tkill(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	int thr = 0;
+	int sig = SIGABRT;
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	if (*args[3])
+		thr = atoi(args[3]);
+
+	if (thr < 0 || thr > global.nbthread)
+		return cli_err(appctx, "Thread number out of range (use 0 for current).\n");
+
+	if (*args[4])
+		sig = atoi(args[4]);
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	if (thr)
+		ha_tkill(thr - 1, sig);
+	else
+		raise(sig);
+	return 1;
+}
+
+/* parse a "debug dev write" command. It always returns 1. */
+static int debug_parse_cli_write(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	unsigned long len;
+
+	if (!*args[3])
+		return cli_err(appctx, "Missing output size.\n");
+
+	len = strtoul(args[3], NULL, 0);
+	if (len >= trash.size)
+		return cli_err(appctx, "Output too large, must be <tune.bufsize.\n");
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+
+	chunk_reset(&trash);
+	trash.data = len;
+	memset(trash.area, '.', trash.data);
+	trash.area[trash.data] = 0;
+	for (len = 64; len < trash.data; len += 64)
+		trash.area[len] = '\n';
+	return cli_msg(appctx, LOG_INFO, trash.area);
+}
+
+/* parse a "debug dev stream" command */
+/*
+ *  debug dev stream [strm=<ptr>] [strm.f[{+-=}<flags>]] [txn.f[{+-=}<flags>]] \
+ *                   [req.f[{+-=}<flags>]] [res.f[{+-=}<flags>]]               \
+ *                   [sif.f[{+-=<flags>]] [sib.f[{+-=<flags>]]                 \
+ *                   [sif.s[=<state>]] [sib.s[=<state>]]
+ */
+static int debug_parse_cli_stream(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	struct stream *s = appctx_strm(appctx);
+	int arg;
+	void *ptr;
+	int size;
+	const char *word, *end;
+	struct ist name;
+	char *msg = NULL;
+	char *endarg;
+	unsigned long long old, new;
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	ptr = NULL; size = 0;
+
+	if (!*args[3]) {
+		return cli_err(appctx,
+			       "Usage: debug dev stream { <obj> <op> <value> | wake }*\n"
+			       "     <obj>   = {strm | strm.f | strm.x | scf.s | scb.s |\n"
+			       "                txn.f | req.f | req.r | req.w | res.f | res.r | res.w}\n"
+			       "     <op>    = {'' (show) | '=' (assign) | '^' (xor) | '+' (or) | '-' (andnot)}\n"
+			       "     <value> = 'now' | 64-bit dec/hex integer (0x prefix supported)\n"
+			       "     'wake' wakes the stream asssigned to 'strm' (default: current)\n"
+			       );
+	}
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	for (arg = 3; *args[arg]; arg++) {
+		old = 0;
+		end = word = args[arg];
+		while (*end && *end != '=' && *end != '^' && *end != '+' && *end != '-')
+			end++;
+		name = ist2(word, end - word);
+		if (isteq(name, ist("strm"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s; size = sizeof(s);
+		} else if (isteq(name, ist("strm.f"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->flags; size = sizeof(s->flags);
+		} else if (isteq(name, ist("strm.x"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->conn_exp; size = sizeof(s->conn_exp);
+		} else if (isteq(name, ist("txn.f"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->txn->flags; size = sizeof(s->txn->flags);
+		} else if (isteq(name, ist("req.f"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->req.flags; size = sizeof(s->req.flags);
+		} else if (isteq(name, ist("res.f"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->res.flags; size = sizeof(s->res.flags);
+		} else if (isteq(name, ist("req.r"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->req.rex; size = sizeof(s->req.rex);
+		} else if (isteq(name, ist("res.r"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->res.rex; size = sizeof(s->res.rex);
+		} else if (isteq(name, ist("req.w"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->req.wex; size = sizeof(s->req.wex);
+		} else if (isteq(name, ist("res.w"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->res.wex; size = sizeof(s->res.wex);
+		} else if (isteq(name, ist("scf.s"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->scf->state; size = sizeof(s->scf->state);
+		} else if (isteq(name, ist("scb.s"))) {
+			ptr = (!s || !may_access(s)) ? NULL : &s->scf->state; size = sizeof(s->scb->state);
+		} else if (isteq(name, ist("wake"))) {
+			if (s && may_access(s) && may_access((void *)s + sizeof(*s) - 1))
+				task_wakeup(s->task, TASK_WOKEN_TIMER|TASK_WOKEN_IO|TASK_WOKEN_MSG);
+			continue;
+		} else
+			return cli_dynerr(appctx, memprintf(&msg, "Unsupported field name: '%s'.\n", word));
+
+		/* read previous value */
+		if ((s || ptr == &s) && ptr && may_access(ptr) && may_access(ptr + size - 1)) {
+			if (size == 8)
+				old = read_u64(ptr);
+			else if (size == 4)
+				old = read_u32(ptr);
+			else if (size == 2)
+				old = read_u16(ptr);
+			else
+				old = *(const uint8_t *)ptr;
+		} else {
+			memprintf(&msg,
+				  "%sSkipping inaccessible pointer %p for field '%.*s'.\n",
+				  msg ? msg : "", ptr, (int)(end - word), word);
+			continue;
+		}
+
+		/* parse the new value . */
+		new = strtoll(end + 1, &endarg, 0);
+		if (end[1] && *endarg) {
+			if (strcmp(end + 1, "now") == 0)
+				new = now_ms;
+			else {
+				memprintf(&msg,
+					  "%sIgnoring unparsable value '%s' for field '%.*s'.\n",
+					  msg ? msg : "", end + 1, (int)(end - word), word);
+				continue;
+			}
+		}
+
+		switch (*end) {
+		case '\0': /* show */
+			memprintf(&msg, "%s%.*s=%#llx ", msg ? msg : "", (int)(end - word), word, old);
+			new = old; // do not change the value
+			break;
+
+		case '=': /* set */
+			break;
+
+		case '^': /* XOR */
+			new = old ^ new;
+			break;
+
+		case '+': /* OR */
+			new = old | new;
+			break;
+
+		case '-': /* AND NOT */
+			new = old & ~new;
+			break;
+
+		default:
+			break;
+		}
+
+		/* write the new value */
+		if (new != old) {
+			if (size == 8)
+				write_u64(ptr, new);
+			else if (size == 4)
+				write_u32(ptr, new);
+			else if (size == 2)
+				write_u16(ptr, new);
+			else
+				*(uint8_t *)ptr = new;
+		}
+	}
+
+	if (msg && *msg)
+		return cli_dynmsg(appctx, LOG_INFO, msg);
+	return 1;
+}
+
+static struct task *debug_task_handler(struct task *t, void *ctx, unsigned int state)
+{
+	unsigned long *tctx = ctx; // [0] = #tasks, [1] = inter, [2+] = { tl | (tsk+1) }
+	unsigned long inter = tctx[1];
+	unsigned long rnd;
+
+	t->expire = tick_add(now_ms, inter);
+
+	/* half of the calls will wake up another entry */
+	rnd = statistical_prng();
+	if (rnd & 1) {
+		rnd >>= 1;
+		rnd %= tctx[0];
+		rnd = tctx[rnd + 2];
+
+		if (rnd & 1)
+			task_wakeup((struct task *)(rnd - 1), TASK_WOKEN_MSG);
+		else
+			tasklet_wakeup((struct tasklet *)rnd);
+	}
+	return t;
+}
+
+static struct task *debug_tasklet_handler(struct task *t, void *ctx, unsigned int state)
+{
+	unsigned long *tctx = ctx; // [0] = #tasks, [1] = inter, [2+] = { tl | (tsk+1) }
+	unsigned long rnd;
+	int i;
+
+	/* wake up two random entries */
+	for (i = 0; i < 2; i++) {
+		rnd = statistical_prng() % tctx[0];
+		rnd = tctx[rnd + 2];
+
+		if (rnd & 1)
+			task_wakeup((struct task *)(rnd - 1), TASK_WOKEN_MSG);
+		else
+			tasklet_wakeup((struct tasklet *)rnd);
+	}
+	return t;
+}
+
+/* parse a "debug dev sched" command
+ * debug dev sched {task|tasklet} [count=<count>] [mask=<mask>] [single=<single>] [inter=<inter>]
+ */
+static int debug_parse_cli_sched(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	int arg;
+	void *ptr;
+	int size;
+	const char *word, *end;
+	struct ist name;
+	char *msg = NULL;
+	char *endarg;
+	unsigned long long new;
+	unsigned long count = 0;
+	unsigned long thrid = 0;
+	unsigned int inter = 0;
+	unsigned long mask, tmask;
+	unsigned long i;
+	int mode = 0; // 0 = tasklet; 1 = task
+	int single = 0;
+	unsigned long *tctx; // [0] = #tasks, [1] = inter, [2+] = { tl | (tsk+1) }
+
+	if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+		return 1;
+
+	ptr = NULL; size = 0;
+	mask = all_threads_mask;
+
+	if (strcmp(args[3], "task") != 0 && strcmp(args[3], "tasklet") != 0) {
+		return cli_err(appctx,
+			       "Usage: debug dev sched {task|tasklet} { <obj> = <value> }*\n"
+			       "     <obj>   = {count | mask | inter | single }\n"
+			       "     <value> = 64-bit dec/hex integer (0x prefix supported)\n"
+			       );
+	}
+
+	mode = strcmp(args[3], "task") == 0;
+
+	_HA_ATOMIC_INC(&debug_commands_issued);
+	for (arg = 4; *args[arg]; arg++) {
+		end = word = args[arg];
+		while (*end && *end != '=' && *end != '^' && *end != '+' && *end != '-')
+			end++;
+		name = ist2(word, end - word);
+		if (isteq(name, ist("count"))) {
+			ptr = &count; size = sizeof(count);
+		} else if (isteq(name, ist("mask"))) {
+			ptr = &mask; size = sizeof(mask);
+		} else if (isteq(name, ist("tid"))) {
+			ptr = &thrid; size = sizeof(thrid);
+		} else if (isteq(name, ist("inter"))) {
+			ptr = &inter; size = sizeof(inter);
+		} else if (isteq(name, ist("single"))) {
+			ptr = &single; size = sizeof(single);
+		} else
+			return cli_dynerr(appctx, memprintf(&msg, "Unsupported setting: '%s'.\n", word));
+
+		/* parse the new value . */
+		new = strtoll(end + 1, &endarg, 0);
+		if (end[1] && *endarg) {
+			memprintf(&msg,
+			          "%sIgnoring unparsable value '%s' for field '%.*s'.\n",
+			          msg ? msg : "", end + 1, (int)(end - word), word);
+			continue;
+		}
+
+		/* write the new value */
+		if (size == 8)
+			write_u64(ptr, new);
+		else if (size == 4)
+			write_u32(ptr, new);
+		else if (size == 2)
+			write_u16(ptr, new);
+		else
+			*(uint8_t *)ptr = new;
+	}
+
+	tctx = calloc(sizeof(*tctx), count + 2);
+	if (!tctx)
+		goto fail;
+
+	tctx[0] = (unsigned long)count;
+	tctx[1] = (unsigned long)inter;
+
+	mask &= all_threads_mask;
+	if (!mask)
+		mask = tid_bit;
+
+	tmask = 0;
+	for (i = 0; i < count; i++) {
+		if (single || mode == 0) {
+			/* look for next bit matching a bit in mask or loop back to zero */
+			for (tmask <<= 1; !(mask & tmask); ) {
+				if (!(mask & -tmask))
+					tmask = 1;
+				else
+					tmask <<= 1;
+			}
+		} else {
+			/* multi-threaded task */
+			tmask = mask;
+		}
+
+		/* now, if poly or mask was set, tmask corresponds to the
+		 * valid thread mask to use, otherwise it remains zero.
+		 */
+		//printf("%lu: mode=%d mask=%#lx\n", i, mode, tmask);
+		if (mode == 0) {
+			struct tasklet *tl = tasklet_new();
+
+			if (!tl)
+				goto fail;
+
+			if (tmask)
+				tl->tid = my_ffsl(tmask) - 1;
+			tl->process = debug_tasklet_handler;
+			tl->context = tctx;
+			tctx[i + 2] = (unsigned long)tl;
+		} else {
+			struct task *task = task_new(tmask ? tmask : tid_bit);
+
+			if (!task)
+				goto fail;
+
+			task->process = debug_task_handler;
+			task->context = tctx;
+			tctx[i + 2] = (unsigned long)task + 1;
+		}
+	}
+
+	/* start the tasks and tasklets */
+	for (i = 0; i < count; i++) {
+		unsigned long ctx = tctx[i + 2];
+
+		if (ctx & 1)
+			task_wakeup((struct task *)(ctx - 1), TASK_WOKEN_INIT);
+		else
+			tasklet_wakeup((struct tasklet *)ctx);
+	}
+
+	if (msg && *msg)
+		return cli_dynmsg(appctx, LOG_INFO, msg);
+	return 1;
+
+ fail:
+	/* free partially allocated entries */
+	for (i = 0; tctx && i < count; i++) {
+		unsigned long ctx = tctx[i + 2];
+
+		if (!ctx)
+			break;
+
+		if (ctx & 1)
+			task_destroy((struct task *)(ctx - 1));
+		else
+			tasklet_free((struct tasklet *)ctx);
+	}
+
+	free(tctx);
+	return cli_err(appctx, "Not enough memory");
+}
+
+/* CLI state for "debug dev fd" */
+struct dev_fd_ctx {
+	int start_fd;
+};
+
+/* CLI parser for the "debug dev fd" command. The current FD to restart from is
+ * stored in a struct dev_fd_ctx pointed to by svcctx.
+ */
+static int debug_parse_cli_fd(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	struct dev_fd_ctx *ctx = applet_reserve_svcctx(appctx, sizeof(*ctx));
+
+	if (!cli_has_level(appctx, ACCESS_LVL_OPER))
+		return 1;
+
+	/* start at fd #0 */
+	ctx->start_fd = 0;
+	return 0;
+}
+
+/* CLI I/O handler for the "debug dev fd" command. Dumps all FDs that are
+ * accessible from the process but not known from fdtab. The FD number to
+ * restart from is stored in a struct dev_fd_ctx pointed to by svcctx.
+ */
+static int debug_iohandler_fd(struct appctx *appctx)
+{
+	struct dev_fd_ctx *ctx = appctx->svcctx;
+	struct stconn *sc = appctx_sc(appctx);
+	struct sockaddr_storage sa;
+	struct stat statbuf;
+	socklen_t salen, vlen;
+	int ret1, ret2, port;
+	char *addrstr;
+	int ret = 1;
+	int i, fd;
+
+	if (unlikely(sc_ic(sc)->flags & (CF_WRITE_ERROR|CF_SHUTW)))
+		goto end;
+
+	chunk_reset(&trash);
+
+	thread_isolate();
+
+	/* we have two inner loops here, one for the proxy, the other one for
+	 * the buffer.
+	 */
+	for (fd = ctx->start_fd; fd < global.maxsock; fd++) {
+		/* check for FD's existence */
+		ret1 = fcntl(fd, F_GETFD, 0);
+		if (ret1 == -1)
+			continue; // not known to the process
+		if (fdtab[fd].owner)
+			continue; // well-known
+
+		/* OK we're seeing an orphan let's try to retrieve as much
+		 * information as possible about it.
+		 */
+		chunk_printf(&trash, "%5d", fd);
+
+		if (fstat(fd, &statbuf) != -1) {
+			chunk_appendf(&trash, " type=%s mod=%04o dev=%#llx siz=%#llx uid=%lld gid=%lld fs=%#llx ino=%#llx",
+				      isatty(fd)                ? "tty.":
+				      S_ISREG(statbuf.st_mode)  ? "file":
+				      S_ISDIR(statbuf.st_mode)  ? "dir.":
+				      S_ISCHR(statbuf.st_mode)  ? "chr.":
+				      S_ISBLK(statbuf.st_mode)  ? "blk.":
+				      S_ISFIFO(statbuf.st_mode) ? "pipe":
+				      S_ISLNK(statbuf.st_mode)  ? "link":
+				      S_ISSOCK(statbuf.st_mode) ? "sock":
+#ifdef USE_EPOLL
+				      epoll_wait(fd, NULL, 0, 0) != -1 || errno != EBADF ? "epol":
+#endif
+				      "????",
+				      (uint)statbuf.st_mode & 07777,
+
+				      (ullong)statbuf.st_rdev,
+				      (ullong)statbuf.st_size,
+				      (ullong)statbuf.st_uid,
+				      (ullong)statbuf.st_gid,
+
+				      (ullong)statbuf.st_dev,
+				      (ullong)statbuf.st_ino);
+		}
+
+		chunk_appendf(&trash, " getfd=%s+%#x",
+			     (ret1 & FD_CLOEXEC) ? "cloex" : "",
+			     ret1 &~ FD_CLOEXEC);
+
+		/* FD options */
+		ret2 = fcntl(fd, F_GETFL, 0);
+		if (ret2) {
+			chunk_appendf(&trash, " getfl=%s",
+				      (ret1 & 3) >= 2 ? "O_RDWR" :
+				      (ret1 & 1) ? "O_WRONLY" : "O_RDONLY");
+
+			for (i = 2; i < 32; i++) {
+				if (!(ret2 & (1UL << i)))
+					continue;
+				switch (1UL << i) {
+				case O_CREAT:   chunk_appendf(&trash, ",O_CREAT");   break;
+				case O_EXCL:    chunk_appendf(&trash, ",O_EXCL");    break;
+				case O_NOCTTY:  chunk_appendf(&trash, ",O_NOCTTY");  break;
+				case O_TRUNC:   chunk_appendf(&trash, ",O_TRUNC");   break;
+				case O_APPEND:  chunk_appendf(&trash, ",O_APPEND");  break;
+#ifdef O_ASYNC
+				case O_ASYNC:   chunk_appendf(&trash, ",O_ASYNC");   break;
+#endif
+#ifdef O_DIRECT
+				case O_DIRECT:  chunk_appendf(&trash, ",O_DIRECT");  break;
+#endif
+#ifdef O_NOATIME
+				case O_NOATIME: chunk_appendf(&trash, ",O_NOATIME"); break;
+#endif
+				}
+			}
+		}
+
+		vlen = sizeof(ret2);
+		ret1 = getsockopt(fd, SOL_SOCKET, SO_TYPE, &ret2, &vlen);
+		if (ret1 != -1)
+			chunk_appendf(&trash, " so_type=%d", ret2);
+
+		vlen = sizeof(ret2);
+		ret1 = getsockopt(fd, SOL_SOCKET, SO_ACCEPTCONN, &ret2, &vlen);
+		if (ret1 != -1)
+			chunk_appendf(&trash, " so_accept=%d", ret2);
+
+		vlen = sizeof(ret2);
+		ret1 = getsockopt(fd, SOL_SOCKET, SO_ERROR, &ret2, &vlen);
+		if (ret1 != -1)
+			chunk_appendf(&trash, " so_error=%d", ret2);
+
+		salen = sizeof(sa);
+		if (getsockname(fd, (struct sockaddr *)&sa, &salen) != -1) {
+			if (sa.ss_family == AF_INET)
+				port = ntohs(((const struct sockaddr_in *)&sa)->sin_port);
+			else if (sa.ss_family == AF_INET6)
+				port = ntohs(((const struct sockaddr_in6 *)&sa)->sin6_port);
+			else
+				port = 0;
+			addrstr = sa2str(&sa, port, 0);
+			chunk_appendf(&trash, " laddr=%s", addrstr);
+			free(addrstr);
+		}
+
+		salen = sizeof(sa);
+		if (getpeername(fd, (struct sockaddr *)&sa, &salen) != -1) {
+			if (sa.ss_family == AF_INET)
+				port = ntohs(((const struct sockaddr_in *)&sa)->sin_port);
+			else if (sa.ss_family == AF_INET6)
+				port = ntohs(((const struct sockaddr_in6 *)&sa)->sin6_port);
+			else
+				port = 0;
+			addrstr = sa2str(&sa, port, 0);
+			chunk_appendf(&trash, " raddr=%s", addrstr);
+			free(addrstr);
+		}
+
+		chunk_appendf(&trash, "\n");
+
+		if (applet_putchk(appctx, &trash) == -1) {
+			ctx->start_fd = fd;
+			ret = 0;
+			break;
+		}
+	}
+
+	thread_release();
+ end:
+	return ret;
+}
+
+#if defined(DEBUG_MEM_STATS)
+
+/* CLI state for "debug dev memstats" */
+struct dev_mem_ctx {
+	struct mem_stats *start, *stop; /* begin/end of dump */
+	int show_all;                   /* show all entries if non-null */
+};
+
+/* CLI parser for the "debug dev memstats" command. Sets a dev_mem_ctx shown above. */
+static int debug_parse_cli_memstats(char **args, char *payload, struct appctx *appctx, void *private)
+{
+	struct dev_mem_ctx *ctx = applet_reserve_svcctx(appctx, sizeof(*ctx));
+
+	extern __attribute__((__weak__)) struct mem_stats __start_mem_stats;
+	extern __attribute__((__weak__)) struct mem_stats __stop_mem_stats;
+
+	if (!cli_has_level(appctx, ACCESS_LVL_OPER))
+		return 1;
+
+	if (strcmp(args[3], "reset") == 0) {
+		struct mem_stats *ptr;
+
+		if (!cli_has_level(appctx, ACCESS_LVL_ADMIN))
+			return 1;
+
+		for (ptr = &__start_mem_stats; ptr < &__stop_mem_stats; ptr++) {
+			_HA_ATOMIC_STORE(&ptr->calls, 0);
+			_HA_ATOMIC_STORE(&ptr->size, 0);
+		}
+		return 1;
+	}
+
+	if (strcmp(args[3], "all") == 0)
+		ctx->show_all = 1;
+
+	/* otherwise proceed with the dump from p0 to p1 */
+	ctx->start = &__start_mem_stats;
+	ctx->stop  = &__stop_mem_stats;
+	return 0;
+}
+
+/* CLI I/O handler for the "debug dev memstats" command using a dev_mem_ctx
+ * found in appctx->svcctx. Dumps all mem_stats structs referenced by pointers
+ * located between ->start and ->stop. Dumps all entries if ->show_all != 0,
+ * otherwise only non-zero calls.
+ */
+static int debug_iohandler_memstats(struct appctx *appctx)
+{
+	struct dev_mem_ctx *ctx = appctx->svcctx;
+	struct stconn *sc = appctx_sc(appctx);
+	struct mem_stats *ptr = ctx->start;
+	int ret = 1;
+
+	if (unlikely(sc_ic(sc)->flags & (CF_WRITE_ERROR|CF_SHUTW)))
+		goto end;
+
+	chunk_reset(&trash);
+
+	/* we have two inner loops here, one for the proxy, the other one for
+	 * the buffer.
+	 */
+	for (; ptr != ctx->stop; ptr++) {
+		const char *type;
+		const char *name;
+		const char *p;
+
+		if (!ptr->size && !ptr->calls && !ctx->show_all)
+			continue;
+
+		/* basename only */
+		for (p = name = ptr->file; *p; p++) {
+			if (*p == '/')
+				name = p + 1;
+		}
+
+		switch (ptr->type) {
+		case MEM_STATS_TYPE_CALLOC:  type = "CALLOC";  break;
+		case MEM_STATS_TYPE_FREE:    type = "FREE";    break;
+		case MEM_STATS_TYPE_MALLOC:  type = "MALLOC";  break;
+		case MEM_STATS_TYPE_REALLOC: type = "REALLOC"; break;
+		case MEM_STATS_TYPE_STRDUP:  type = "STRDUP";  break;
+		default:                     type = "UNSET";   break;
+		}
+
+		//chunk_printf(&trash,
+		//	     "%20s:%-5d %7s size: %12lu calls: %9lu size/call: %6lu\n",
+		//	     name, ptr->line, type,
+		//	     (unsigned long)ptr->size, (unsigned long)ptr->calls,
+		//	     (unsigned long)(ptr->calls ? (ptr->size / ptr->calls) : 0));
+
+		chunk_printf(&trash, "%s:%d", name, ptr->line);
+		while (trash.data < 25)
+			trash.area[trash.data++] = ' ';
+		chunk_appendf(&trash, "%7s  size: %12lu  calls: %9lu  size/call: %6lu\n",
+			     type,
+			     (unsigned long)ptr->size, (unsigned long)ptr->calls,
+			     (unsigned long)(ptr->calls ? (ptr->size / ptr->calls) : 0));
+
+		if (applet_putchk(appctx, &trash) == -1) {
+			ctx->start = ptr;
+			ret = 0;
+			break;
+		}
+	}
+
+ end:
+	return ret;
+}
+
+#endif
+
+#ifndef USE_THREAD_DUMP
+
+/* This function dumps all threads' state to the trash. This version is the
+ * most basic one, which doesn't inspect other threads.
+ */
+void ha_thread_dump_all_to_trash()
+{
+	unsigned int thr;
+
+	for (thr = 0; thr < global.nbthread; thr++)
+		ha_thread_dump(&trash, thr, tid);
+}
+
+#else /* below USE_THREAD_DUMP is set */
+
+/* ID of the thread requesting the dump */
+static unsigned int thread_dump_tid;
+
+/* points to the buffer where the dump functions should write. It must
+ * have already been initialized by the requester. Nothing is done if
+ * it's NULL.
+ */
+struct buffer *thread_dump_buffer = NULL;
+
+void ha_thread_dump_all_to_trash()
+{
+	unsigned long old;
+
+	while (1) {
+		old = 0;
+		if (HA_ATOMIC_CAS(&threads_to_dump, &old, all_threads_mask))
+			break;
+		ha_thread_relax();
+	}
+
+	thread_dump_buffer = &trash;
+	thread_dump_tid = tid;
+	ha_tkillall(DEBUGSIG);
+}
+
+/* handles DEBUGSIG to dump the state of the thread it's working on */
+void debug_handler(int sig, siginfo_t *si, void *arg)
+{
+	/* first, let's check it's really for us and that we didn't just get
+	 * a spurious DEBUGSIG.
+	 */
+	if (!(threads_to_dump & tid_bit))
+		return;
+
+	/* There are 4 phases in the dump process:
+	 *   1- wait for our turn, i.e. when all lower bits are gone.
+	 *   2- perform the action if our bit is set
+	 *   3- remove our bit to let the next one go, unless we're
+	 *      the last one and have to put them all as a signal
+	 *   4- wait out bit to re-appear, then clear it and quit.
+	 */
+
+	/* wait for all previous threads to finish first */
+	while (threads_to_dump & (tid_bit - 1))
+		ha_thread_relax();
+
+	/* dump if needed */
+	if (threads_to_dump & tid_bit) {
+		if (thread_dump_buffer)
+			ha_thread_dump(thread_dump_buffer, tid, thread_dump_tid);
+		if ((threads_to_dump & all_threads_mask) == tid_bit) {
+			/* last one */
+			HA_ATOMIC_STORE(&threads_to_dump, all_threads_mask);
+			thread_dump_buffer = NULL;
+		}
+		else
+			HA_ATOMIC_AND(&threads_to_dump, ~tid_bit);
+	}
+
+	/* now wait for all others to finish dumping. The last one will set all
+	 * bits again to broadcast the leaving condition so we'll see ourselves
+	 * present again. This way the threads_to_dump variable never passes to
+	 * zero until all visitors have stopped waiting.
+	 */
+	while (!(threads_to_dump & tid_bit))
+		ha_thread_relax();
+	HA_ATOMIC_AND(&threads_to_dump, ~tid_bit);
+
+	/* mark the current thread as stuck to detect it upon next invocation
+	 * if it didn't move.
+	 */
+	if (!((threads_harmless_mask|sleeping_thread_mask) & tid_bit))
+		th_ctx->flags |= TH_FL_STUCK;
+}
+
+static int init_debug_per_thread()
+{
+	sigset_t set;
+
+	/* unblock the DEBUGSIG signal we intend to use */
+	sigemptyset(&set);
+	sigaddset(&set, DEBUGSIG);
+	ha_sigmask(SIG_UNBLOCK, &set, NULL);
+	return 1;
+}
+
+static int init_debug()
+{
+	struct sigaction sa;
+	void *callers[1];
+
+	/* calling backtrace() will access libgcc at runtime. We don't want to
+	 * do it after the chroot, so let's perform a first call to have it
+	 * ready in memory for later use.
+	 */
+	my_backtrace(callers, sizeof(callers)/sizeof(*callers));
+	sa.sa_handler = NULL;
+	sa.sa_sigaction = debug_handler;
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = SA_SIGINFO;
+	sigaction(DEBUGSIG, &sa, NULL);
+	return ERR_NONE;
+}
+
+REGISTER_POST_CHECK(init_debug);
+REGISTER_PER_THREAD_INIT(init_debug_per_thread);
+
+#endif /* USE_THREAD_DUMP */
+
+/* register cli keywords */
+static struct cli_kw_list cli_kws = {{ },{
+	{{ "debug", "dev", "bug", NULL },      "debug dev bug                           : call BUG_ON() and crash",                 debug_parse_cli_bug,   NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "check", NULL },    "debug dev check                         : call CHECK_IF() and possibly crash",      debug_parse_cli_check, NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "close", NULL },    "debug dev close  <fd>                   : close this file descriptor",              debug_parse_cli_close, NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "delay", NULL },    "debug dev delay  [ms]                   : sleep this long",                         debug_parse_cli_delay, NULL, NULL, NULL, ACCESS_EXPERT },
+#if defined(DEBUG_DEV)
+	{{ "debug", "dev", "exec",  NULL },    "debug dev exec   [cmd] ...              : show this command's output",              debug_parse_cli_exec,  NULL, NULL, NULL, ACCESS_EXPERT },
+#endif
+	{{ "debug", "dev", "fd", NULL },       "debug dev fd                            : scan for rogue/unhandled FDs",            debug_parse_cli_fd,    debug_iohandler_fd, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "exit",  NULL },    "debug dev exit   [code]                 : immediately exit the process",            debug_parse_cli_exit,  NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "hex",   NULL },    "debug dev hex    <addr> [len]           : dump a memory area",                      debug_parse_cli_hex,   NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "log",   NULL },    "debug dev log    [msg] ...              : send this msg to global logs",            debug_parse_cli_log,   NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "loop",  NULL },    "debug dev loop   [ms]                   : loop this long",                          debug_parse_cli_loop,  NULL, NULL, NULL, ACCESS_EXPERT },
+#if defined(DEBUG_MEM_STATS)
+	{{ "debug", "dev", "memstats", NULL }, "debug dev memstats [reset|all]          : dump/reset memory statistics",            debug_parse_cli_memstats, debug_iohandler_memstats, NULL, NULL, ACCESS_EXPERT },
+#endif
+	{{ "debug", "dev", "panic", NULL },    "debug dev panic                         : immediately trigger a panic",             debug_parse_cli_panic, NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "sched", NULL },    "debug dev sched  {task|tasklet} [k=v]*  : stress the scheduler",                    debug_parse_cli_sched, NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "stream",NULL },    "debug dev stream [k=v]*                 : show/manipulate stream flags",            debug_parse_cli_stream,NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "sym",   NULL },    "debug dev sym    <addr>                 : resolve symbol address",                  debug_parse_cli_sym,   NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "tkill", NULL },    "debug dev tkill  [thr] [sig]            : send signal to thread",                   debug_parse_cli_tkill, NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "warn",  NULL },    "debug dev warn                          : call WARN_ON() and possibly crash",       debug_parse_cli_warn,  NULL, NULL, NULL, ACCESS_EXPERT },
+	{{ "debug", "dev", "write", NULL },    "debug dev write  [size]                 : write that many bytes in return",         debug_parse_cli_write, NULL, NULL, NULL, ACCESS_EXPERT },
+#if defined(HA_HAVE_DUMP_LIBS)
+	{{ "show", "libs", NULL, NULL },       "show libs                               : show loaded object files and libraries", debug_parse_cli_show_libs, NULL, NULL },
+#endif
+	{{ "show", "threads", NULL, NULL },    "show threads                            : show some threads debugging information", NULL, cli_io_handler_show_threads, NULL },
+	{{},}
+}};
+
+INITCALL1(STG_REGISTER, cli_register_kw, &cli_kws);