1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2007 Robert N. M. Watson
5 * Copyright (c) 2015 Allan Jude <allanjude@freebsd.org>
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/param.h>
31#include <sys/sysctl.h>
32#include <sys/user.h>
33
34#include <err.h>
35#include <errno.h>
36#include <libprocstat.h>
37#include <stdio.h>
38#include <stdlib.h>
39#include <string.h>
40
41#include "procstat.h"
42
43/*
44 * Walk the stack trace provided by the kernel and reduce it to what we
45 * actually want to print.  This involves stripping true instruction pointers,
46 * frame numbers, and carriage returns as generated by stack(9).  If -kk is
47 * specified, print the function and offset, otherwise just the function.
48 */
49enum trace_state { TS_FRAMENUM, TS_PC, TS_AT, TS_FUNC, TS_OFF };
50
51static enum trace_state
52kstack_nextstate(enum trace_state ts)
53{
54
55	switch (ts) {
56	case TS_FRAMENUM:
57		return (TS_PC);
58
59	case TS_PC:
60		return (TS_AT);
61
62	case TS_AT:
63		return (TS_FUNC);
64
65	case TS_FUNC:
66		return (TS_OFF);
67
68	case TS_OFF:
69		return (TS_FRAMENUM);
70
71	default:
72		errx(-1, "kstack_nextstate");
73	}
74}
75
76static void
77kstack_cleanup(const char *old, char *new, int kflag)
78{
79	enum trace_state old_ts, ts;
80	const char *cp_old;
81	char *cp_new;
82
83	ts = TS_FRAMENUM;
84	for (cp_old = old, cp_new = new; *cp_old != '\0'; cp_old++) {
85		switch (*cp_old) {
86		case ' ':
87		case '\n':
88		case '+':
89			old_ts = ts;
90			ts = kstack_nextstate(old_ts);
91			if (old_ts == TS_OFF) {
92				*cp_new = ' ';
93				cp_new++;
94			}
95			if (kflag > 1 && old_ts == TS_FUNC) {
96				*cp_new = '+';
97				cp_new++;
98			}
99			continue;
100		}
101		if (ts == TS_FUNC || (kflag > 1 && ts == TS_OFF)) {
102			*cp_new = *cp_old;
103			cp_new++;
104		}
105	}
106	*cp_new = '\0';
107}
108
109static void
110kstack_cleanup_encoded(const char *old, char *new, int kflag)
111{
112	enum trace_state old_ts, ts;
113	const char *cp_old;
114	char *cp_new, *cp_loop, *cp_tofree, *cp_line;
115
116	ts = TS_FRAMENUM;
117	if (kflag == 1) {
118		for (cp_old = old, cp_new = new; *cp_old != '\0'; cp_old++) {
119			switch (*cp_old) {
120			case '\n':
121				*cp_new = *cp_old;
122				cp_new++;
123			case ' ':
124			case '+':
125				old_ts = ts;
126				ts = kstack_nextstate(old_ts);
127				continue;
128			}
129			if (ts == TS_FUNC) {
130				*cp_new = *cp_old;
131				cp_new++;
132			}
133		}
134		*cp_new = '\0';
135		cp_tofree = cp_loop = strdup(new);
136	} else
137		cp_tofree = cp_loop = strdup(old);
138        while ((cp_line = strsep(&cp_loop, "\n")) != NULL) {
139		if (strlen(cp_line) != 0 && *cp_line != 127)
140			xo_emit("{le:token/%s}", cp_line);
141	}
142	free(cp_tofree);
143}
144
145/*
146 * Sort threads by tid.
147 */
148static int
149kinfo_kstack_compare(const void *a, const void *b)
150{
151
152        return ((const struct kinfo_kstack *)a)->kkst_tid -
153            ((const struct kinfo_kstack *)b)->kkst_tid;
154}
155
156static void
157kinfo_kstack_sort(struct kinfo_kstack *kkstp, int count)
158{
159
160        qsort(kkstp, count, sizeof(*kkstp), kinfo_kstack_compare);
161}
162
163
164void
165procstat_kstack(struct procstat *procstat, struct kinfo_proc *kipp)
166{
167	struct kinfo_kstack *kkstp, *kkstp_free;
168	struct kinfo_proc *kip, *kip_free;
169	char trace[KKST_MAXLEN], encoded_trace[KKST_MAXLEN];
170	unsigned int i, j;
171	unsigned int kip_count, kstk_count;
172
173	if ((procstat_opts & PS_OPT_NOHEADER) == 0)
174		xo_emit("{T:/%5s %6s %-19s %-19s %-29s}\n", "PID", "TID", "COMM",
175		    "TDNAME", "KSTACK");
176
177	kkstp = kkstp_free = procstat_getkstack(procstat, kipp, &kstk_count);
178	if (kkstp == NULL)
179		return;
180
181	/*
182	 * We need to re-query for thread information, so don't use *kipp.
183	 */
184	kip = kip_free = procstat_getprocs(procstat,
185	    KERN_PROC_PID | KERN_PROC_INC_THREAD, kipp->ki_pid, &kip_count);
186
187	if (kip == NULL) {
188		procstat_freekstack(procstat, kkstp_free);
189		return;
190	}
191
192	kinfo_kstack_sort(kkstp, kstk_count);
193	for (i = 0; i < kstk_count; i++) {
194		kkstp = &kkstp_free[i];
195
196		/*
197		 * Look up the specific thread using its tid so we can
198		 * display the per-thread command line.
199		 */
200		kipp = NULL;
201		for (j = 0; j < kip_count; j++) {
202			kipp = &kip_free[j];
203			if (kkstp->kkst_tid == kipp->ki_tid)
204				break;
205		}
206		if (kipp == NULL)
207			continue;
208
209		xo_emit("{k:process_id/%5d/%d} ", kipp->ki_pid);
210		xo_emit("{:thread_id/%6d/%d} ", kkstp->kkst_tid);
211		xo_emit("{:command/%-19s/%s} ", kipp->ki_comm);
212		xo_emit("{:thread_name/%-19s/%s} ",
213                    kinfo_proc_thread_name(kipp));
214
215		switch (kkstp->kkst_state) {
216		case KKST_STATE_RUNNING:
217			xo_emit("{:state/%-29s/%s}\n", "<running>");
218			continue;
219
220		case KKST_STATE_SWAPPED:
221			xo_emit("{:state/%-29s/%s}\n", "<swapped>");
222			continue;
223
224		case KKST_STATE_STACKOK:
225			break;
226
227		default:
228			xo_emit("{:state/%-29s/%s}\n", "<unknown>");
229			continue;
230		}
231
232		/*
233		 * The kernel generates a trace with carriage returns between
234		 * entries, but for a more compact view, we convert carriage
235		 * returns to spaces.
236		 */
237		kstack_cleanup(kkstp->kkst_trace, trace,
238		    (procstat_opts & PS_OPT_VERBOSE) != 0 ? 2 : 1);
239		xo_open_list("trace");
240		kstack_cleanup_encoded(kkstp->kkst_trace, encoded_trace,
241		    (procstat_opts & PS_OPT_VERBOSE) != 0 ? 2 : 1);
242		xo_close_list("trace");
243		xo_emit("{d:trace/%-29s}\n", trace);
244	}
245	procstat_freekstack(procstat, kkstp_free);
246	procstat_freeprocs(procstat, kip_free);
247}
248