Add procstat(1), a process inspection utility. This provides both some

of the missing functionality from procfs(4) and new functionality for
monitoring and debugging specific processes.  procstat(1) operates in
the following modes:

  -b  Display binary information for the process.
  -c  Display command line arguments for the process.
  -f  Display file descriptor information for the process.
  -k  Display the stacks of kernel threads in the process.
  -s  Display security credential information for the process.
  -t  Display thread information for the process.
  -v  Display virtual memory mappings for the process.

Further revision and modes are expected.

Testing, ideas, etc:	cognet, sam, Skip Ford <skip at menantico dot com>
			Wesley Shields <wxs at atarininja dot org>

1 files changed, 198 insertions, 0 deletions

diff --git a/usr.bin/procstat/procstat_kstack.c b/usr.bin/procstat/procstat_kstack.c
new file mode 100644
index 0000000..c36720a
--- /dev/null
+++ b/usr.bin/procstat/procstat_kstack.c
@@ -0,0 +1,198 @@
+/*-
+ * Copyright (c) 2007 Robert N. M. Watson
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <sys/user.h>
+
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "procstat.h"
+
+/*
+ * Walk the stack trace provided by the kernel and reduce it to what we
+ * actually want to print.  This involves stripping true instruction pointers,
+ * frame numbers, and carriage returns as generated by stack(9).  If -kk is
+ * specified, print the function and offset, otherwise just the function.
+ */
+enum trace_state { TS_FRAMENUM, TS_PC, TS_AT, TS_FUNC, TS_OFF };
+
+static enum trace_state
+kstack_nextstate(enum trace_state ts)
+{
+
+	switch (ts) {
+	case TS_FRAMENUM:
+		return (TS_PC);
+
+	case TS_PC:
+		return (TS_AT);
+
+	case TS_AT:
+		return (TS_FUNC);
+
+	case TS_FUNC:
+		return (TS_OFF);
+
+	case TS_OFF:
+		return TS_FRAMENUM;
+
+	default:
+		errx(-1, "kstack_nextstate");
+	}
+}
+
+static void
+kstack_cleanup(const char *old, char *new, int kflag)
+{
+	enum trace_state old_ts, ts;
+	const char *cp_old;
+	char *cp_new;
+
+	ts = TS_FRAMENUM;
+	for (cp_old = old, cp_new = new; *cp_old != '\0'; cp_old++) {
+		switch (*cp_old) {
+		case ' ':
+		case '\n':
+		case '+':
+			old_ts = ts;
+			ts = kstack_nextstate(old_ts);
+			if (old_ts == TS_OFF) {
+				*cp_new = ' ';
+				cp_new++;
+			}
+			if (kflag > 1 && old_ts == TS_FUNC) {
+				*cp_new = '+';
+				cp_new++;
+			}
+			continue;
+		}
+		if (ts == TS_FUNC || (kflag > 1 && ts == TS_OFF)) {
+			*cp_new = *cp_old;
+			cp_new++;
+		}
+	}
+	*cp_new = '\0';
+}
+
+/*
+ * Sort threads by tid.
+ */
+static int
+kinfo_kstack_compare(const void *a, const void *b)
+{
+
+        return ((struct kinfo_kstack *)a)->kkst_tid -
+            ((struct kinfo_kstack *)b)->kkst_tid;
+}
+
+static void
+kinfo_kstack_sort(struct kinfo_kstack *kkstp, int count)
+{
+
+        qsort(kkstp, count, sizeof(*kkstp), kinfo_kstack_compare);
+}
+
+
+void
+procstat_kstack(pid_t pid, struct kinfo_proc *kipp, int kflag)
+{
+	struct kinfo_kstack *kkstp, *kkstp_free;
+	char trace[KKST_MAXLEN];
+	int error, i, name[4];
+	size_t len;
+
+	if (!hflag)
+		printf("%5s %6s %-20s %-45s\n", "PID", "TID", "COMM",
+		    "KSTACK");
+
+	name[0] = CTL_KERN;
+	name[1] = KERN_PROC;
+	name[2] = KERN_PROC_KSTACK;
+	name[3] = pid;
+
+	len = 0;
+	error = sysctl(name, 4, NULL, &len, NULL, 0);
+	if (error < 0 && errno != ESRCH && errno != EPERM && errno != ENOENT) {
+		warn("sysctl: kern.proc.kstack: %d", pid);
+		return;
+	}
+	if (error < 0 && errno == ENOENT)
+		errx(-1, "kern.proc.kstack sysctl unavailable; options DDB "
+		    "is required.");
+	if (error < 0)
+		return;
+
+	kkstp = kkstp_free = malloc(len);
+	if (kkstp == NULL)
+		err(-1, "malloc");
+
+	if (sysctl(name, 4, kkstp, &len, NULL, 0) < 0) {
+		warn("sysctl: kern.proc.pid: %d", pid);
+		free(kkstp);
+		return;
+	}
+
+	kinfo_kstack_sort(kkstp, len / sizeof(*kkstp));
+	for (i = 0; i < len / sizeof(*kkstp); i++) {
+		kkstp = &kkstp_free[i];
+		printf("%5d ", pid);
+		printf("%6d ", kkstp->kkst_tid);
+		printf("%-20s ", kipp->ki_comm);
+
+		switch (kkstp->kkst_state) {
+		case KKST_STATE_RUNNING:
+			printf("%-45s\n", "<running>");
+			continue;
+
+		case KKST_STATE_SWAPPED:
+			printf("%-45s\n", "<swapped>");
+			continue;
+
+		case KKST_STATE_STACKOK:
+			break;
+
+		default:
+			printf("%-45s\n", "<unknown>");
+			continue;
+		}
+
+		/*
+		 * The kernel generates a trace with carriage returns between
+		 * entries, but for a more compact view, we convert carriage
+		 * returns to spaces.
+		 */
+		kstack_cleanup(kkstp->kkst_trace, trace, kflag);
+		printf("%-45s\n", trace);
+	}
+	free(kkstp_free);
+}