xref: /freebsd/lib/libprocstat/libprocstat.3 (revision 1d386b48a555f61cb7325543adbbb5c3f3407a66)
1.\" Copyright (c) 2011 Sergey Kandaurov <pluknet@FreeBSD.org>
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25.\" $FreeBSD$
26.\"
27.Dd April 3, 2022
28.Dt LIBPROCSTAT 3
29.Os
30.Sh NAME
31.Nm procstat_close ,
32.Nm procstat_freeadvlock ,
33.Nm procstat_freeargv ,
34.Nm procstat_freeauxv ,
35.Nm procstat_freeenvv ,
36.Nm procstat_freefiles ,
37.Nm procstat_freegroups ,
38.Nm procstat_freekstack ,
39.Nm procstat_freeprocs ,
40.Nm procstat_freeptlwpinfo ,
41.Nm procstat_freevmmap ,
42.Nm procstat_get_pipe_info ,
43.Nm procstat_get_pts_info ,
44.Nm procstat_get_sem_info ,
45.Nm procstat_get_shm_info ,
46.Nm procstat_get_socket_info ,
47.Nm procstat_get_vnode_info ,
48.Nm procstat_getadvlock ,
49.Nm procstat_getargv ,
50.Nm procstat_getauxv ,
51.Nm procstat_getenvv ,
52.Nm procstat_getfiles ,
53.Nm procstat_getgroups ,
54.Nm procstat_getkstack ,
55.Nm procstat_getosrel ,
56.Nm procstat_getpathname ,
57.Nm procstat_getprocs ,
58.Nm procstat_getptlwpinfo ,
59.Nm procstat_getrlimit ,
60.Nm procstat_getumask ,
61.Nm procstat_getvmmap ,
62.Nm procstat_open_core ,
63.Nm procstat_open_kvm ,
64.Nm procstat_open_sysctl
65.Nd library interface for file and process information retrieval
66.Sh LIBRARY
67.Lb libprocstat
68.Sh SYNOPSIS
69.In sys/param.h
70.In sys/queue.h
71.In sys/socket.h
72.In libprocstat.h
73.Ft void
74.Fn procstat_close "struct procstat *procstat"
75.Ft void
76.Fn procstat_freeadvlock "struct procstat *procstat" "struct advlock_list *list"
77.Ft void
78.Fo procstat_freeargv
79.Fa "struct procstat *procstat"
80.Fc
81.Ft void
82.Fo procstat_freeauxv
83.Fa "struct procstat *procstat"
84.Fa "Elf_Auxinfo *auxv"
85.Fc
86.Ft void
87.Fo procstat_freeenvv
88.Fa "struct procstat *procstat"
89.Fc
90.Ft void
91.Fo procstat_freefiles
92.Fa "struct procstat *procstat"
93.Fa "struct filestat_list *head"
94.Fc
95.Ft void
96.Fo procstat_freegroups
97.Fa "struct procstat *procstat"
98.Fa "gid_t *groups"
99.Fc
100.Ft void
101.Fo procstat_freekstack
102.Fa "struct procstat *procstat"
103.Fa "struct kinfo_kstack *kkstp"
104.Fc
105.Ft void
106.Fn procstat_freeprocs "struct procstat *procstat" "struct kinfo_proc *p"
107.Ft void
108.Fo procstat_freevmmap
109.Fa "struct procstat *procstat"
110.Fa "struct kinfo_vmentry *vmmap"
111.Fc
112.Ft void
113.Fo procstat_freeptlwpinfo
114.Fa "struct procstat *procstat"
115.Fa "struct ptrace_lwpinfo *pl"
116.Fc
117.Ft int
118.Fo procstat_get_pipe_info
119.Fa "struct procstat *procstat"
120.Fa "struct filestat *fst"
121.Fa "struct pipestat *pipe"
122.Fa "char *errbuf"
123.Fc
124.Ft int
125.Fo procstat_get_pts_info
126.Fa "struct procstat *procstat"
127.Fa "struct filestat *fst"
128.Fa "struct ptsstat *pts"
129.Fa "char *errbuf"
130.Fc
131.Ft int
132.Fo procstat_get_sem_info
133.Fa "struct procstat *procstat"
134.Fa "struct filestat *fst"
135.Fa "struct semstat *sem"
136.Fa "char *errbuf"
137.Fc
138.Ft int
139.Fo procstat_get_shm_info
140.Fa "struct procstat *procstat"
141.Fa "struct filestat *fst"
142.Fa "struct shmstat *shm"
143.Fa "char *errbuf"
144.Fc
145.Ft int
146.Fo procstat_get_socket_info
147.Fa "struct procstat *procstat"
148.Fa "struct filestat *fst"
149.Fa "struct sockstat *sock"
150.Fa "char *errbuf"
151.Fc
152.Ft int
153.Fo procstat_get_vnode_info
154.Fa "struct procstat *procstat"
155.Fa "struct filestat *fst"
156.Fa "struct vnstat *vn"
157.Fa "char *errbuf"
158.Fc
159.Ft "struct advlock_list *"
160.Fo procstat_getadvlock
161.Fa "struct procstat *procstat"
162.Fc
163.Ft "char **"
164.Fo procstat_getargv
165.Fa "struct procstat *procstat"
166.Fa "const struct kinfo_proc *kp"
167.Fa "size_t nchr"
168.Fc
169.Ft "Elf_Auxinfo *"
170.Fo procstat_getauxv
171.Fa "struct procstat *procstat"
172.Fa "struct kinfo_proc *kp"
173.Fa "unsigned int *count"
174.Fc
175.Ft "char **"
176.Fo procstat_getenvv
177.Fa "struct procstat *procstat"
178.Fa "const struct kinfo_proc *kp"
179.Fa "size_t nchr"
180.Fc
181.Ft "struct filestat_list *"
182.Fo procstat_getfiles
183.Fa "struct procstat *procstat"
184.Fa "struct kinfo_proc *kp"
185.Fa "int mmapped"
186.Fc
187.Ft "gid_t *"
188.Fo procstat_getgroups
189.Fa "struct procstat *procstat"
190.Fa "struct kinfo_proc *kp"
191.Fa "unsigned int *count"
192.Fc
193.Ft "struct kinfo_kstack *"
194.Fo procstat_getkstack
195.Fa "struct procstat *procstat"
196.Fa "struct kinfo_proc *kp"
197.Fa "unsigned int *count"
198.Fc
199.Ft int
200.Fo procstat_getosrel
201.Fa "struct procstat *procstat"
202.Fa "struct kinfo_proc *kp"
203.Fa "int *osrelp"
204.Fc
205.Ft "int"
206.Fo procstat_getpathname
207.Fa "struct procstat *procstat"
208.Fa "struct kinfo_proc *kp"
209.Fa "char *pathname"
210.Fa "size_t maxlen"
211.Fc
212.Ft "struct kinfo_proc *"
213.Fo procstat_getprocs
214.Fa "struct procstat *procstat"
215.Fa "int what"
216.Fa "int arg"
217.Fa "unsigned int *count"
218.Fc
219.Ft "struct ptrace_lwpinfo *"
220.Fo procstat_getptlwpinfo
221.Fa "struct procstat *procstat"
222.Fa "unsigned int *count"
223.Fc
224.Ft "int"
225.Fo procstat_getrlimit
226.Fa "struct procstat *procstat"
227.Fa "struct kinfo_proc *kp"
228.Fa "int which"
229.Fa "struct rlimit* rlimit"
230.Fc
231.Ft "int"
232.Fo procstat_getumask
233.Fa "struct procstat *procstat"
234.Fa "struct kinfo_proc *kp"
235.Fa "unsigned short *maskp"
236.Fc
237.Ft "struct kinfo_vmentry *"
238.Fo procstat_getvmmap
239.Fa "struct procstat *procstat"
240.Fa "struct kinfo_proc *kp"
241.Fa "unsigned int *count"
242.Fc
243.Ft "struct procstat *"
244.Fn procstat_open_core "const char *filename"
245.Ft "struct procstat *"
246.Fn procstat_open_kvm "const char *nlistf" "const char *memf"
247.Ft "struct procstat *"
248.Fn procstat_open_sysctl void
249.Sh DESCRIPTION
250The
251.Nm libprocstat
252library contains the API for runtime file and process information
253retrieval from the running kernel via the
254.Xr sysctl 3
255library backend, and for post-mortem analysis via the
256.Xr kvm 3
257library backend, or from the process
258.Xr core 5
259file, searching for statistics in special
260.Xr elf 3
261note sections.
262.Pp
263The
264.Fn procstat_open_kvm
265and
266.Fn procstat_open_sysctl
267functions use the
268.Xr kvm 3
269or
270.Xr sysctl 3
271library routines, respectively, to access kernel state information
272used to retrieve processes and files states.
273The
274.Fn procstat_open_core
275uses
276.Xr elf 3
277routines to access statistics stored as a set of notes in a process
278.Xr core 5
279file, written by the kernel at the moment of the process abnormal termination.
280The
281.Fa filename
282argument is the process core file name.
283The
284.Fa nlistf
285argument is the executable image of the kernel being examined.
286If this argument is
287.Dv NULL ,
288the currently running kernel is assumed.
289The
290.Fa memf
291argument is the kernel memory device file.
292If this argument is
293.Dv NULL ,
294then
295.Pa /dev/mem
296is assumed.
297See
298.Xr kvm_open 3
299for more details.
300The functions dynamically allocate and return a
301.Vt procstat
302structure pointer used in the rest of the
303.Nm libprocstat
304library routines until the corresponding
305.Fn procstat_close
306call that cleans up the resources allocated by the
307.Fn procstat_open_*
308functions.
309.Pp
310The
311.Fn procstat_getprocs
312function gets a pointer to the
313.Vt procstat
314structure from one of the
315.Fn procstat_open_*
316functions and returns a dynamically allocated (sub-)set of active processes
317in the kernel filled in to array of
318.Vt kinfo_proc
319structures.
320The
321.Fa what
322and
323.Fa arg
324arguments constitute a filtering predicate as described in the
325.Xr kvm_getprocs 3
326function.
327The number of processes found is returned in the reference parameter
328.Fa cnt .
329The caller is responsible to free the allocated memory with a subsequent
330.Fn procstat_freeprocs
331function call.
332.Pp
333The
334.Fn procstat_getptlwpinfo
335function gets a pointer to the
336.Vt procstat
337structure from the
338.Fn procstat_open_core
339function and returns a dynamically allocated set of signals intercepted by a
340process in the process's core file.
341The number of processes found is returned in the reference parameter
342.Fa cnt .
343The caller is responsible to free the allocated memory with a subsequent
344.Fn procstat_freeptlwpinfo
345function call.
346.Pp
347The
348.Fn procstat_getargv
349function gets a pointer to the
350.Vt procstat
351structure from one of the
352.Fn procstat_open_*
353functions, a pointer to
354.Vt kinfo_proc
355structure from the array obtained from the
356.Fn procstat_getprocs
357function, and returns a null-terminated argument vector that corresponds to
358the command line arguments passed to the process.
359The
360.Fa nchr
361argument indicates the maximum number of characters, including null bytes,
362to use in building the strings.
363If this amount is exceeded, the string causing the overflow is truncated and
364the partial result is returned.
365This is handy for programs that print only a one line summary of a
366command and should not copy out large amounts of text only to ignore it.
367If
368.Fa nchr
369is zero, no limit is imposed and all argument strings are returned.
370The values of the returned argument vector refer the strings stored
371in the
372.Vt procstat
373internal buffer.
374A subsequent call of the function with the same
375.Vt procstat
376argument will reuse the buffer.
377To free the allocated memory
378.Fn procstat_freeargv
379function call can be used, or it will be released on
380.Fn procstat_close .
381.Pp
382The
383.Fn procstat_getenvv
384function is similar to
385.Fn procstat_getargv
386but returns the vector of environment strings.
387The caller may free the allocated memory with a subsequent
388.Fn procstat_freeenvv
389function call.
390.Pp
391The
392.Fn procstat_getauxv
393function gets a pointer to the
394.Vt procstat
395structure, a pointer to
396.Vt kinfo_proc
397structure, and returns the auxiliary vector as a dynamically allocated array of
398.Vt Elf_Auxinfo
399elements.
400The caller is responsible to free the allocated memory with a subsequent
401.Fn procstat_freeauxv
402function call.
403.Pp
404The
405.Fn procstat_getfiles
406function gets a pointer to the
407.Vt procstat
408structure initialized with one of the
409.Fn procstat_open_*
410functions, a pointer to
411.Vt kinfo_proc
412structure from the array obtained from the
413.Fn procstat_getprocs
414function, and returns a dynamically allocated linked list of filled in
415.Vt filestat_list
416structures using the STAILQ macros defined in
417.Xr queue 3 .
418The caller is responsible to free the allocated memory with a subsequent
419.Fn procstat_freefiles
420function call.
421.Pp
422The
423.Fn procstat_getgroups
424function gets a pointer to the
425.Vt procstat
426structure, a pointer to
427.Vt kinfo_proc
428structure, and returns the process groups as a dynamically allocated array of
429.Vt gid_t
430elements.
431The caller is responsible to free the allocated memory with a subsequent
432.Fn procstat_freegroups
433function call.
434.Pp
435The
436.Fn procstat_getkstack
437function gets a pointer to the
438.Vt procstat
439structure initialized with one of the
440.Fn procstat_open_*
441functions, a pointer to
442.Vt kinfo_proc
443structure, and returns kernel stacks of the process as a dynamically allocated
444array of
445.Vt kinfo_kstack
446structures.
447The caller is responsible to free the allocated memory with a subsequent
448.Fn procstat_freekstack
449function call.
450.Pp
451The
452.Fn procstat_getosrel
453function gets a pointer to the
454.Vt procstat
455structure, a pointer to
456.Vt kinfo_proc
457structure, and returns osrel date in the 3rd reference parameter.
458.Pp
459The
460.Fn procstat_getpathname
461function gets a pointer to the
462.Vt procstat
463structure, a pointer to
464.Vt kinfo_proc
465structure, and copies the path of the process executable to
466.Fa pathname
467buffer, limiting to
468.Fa maxlen
469characters.
470.Pp
471The
472.Fn procstat_getrlimit
473function gets a pointer to the
474.Vt procstat
475structure, a pointer to
476.Vt kinfo_proc
477structure, resource index
478.Fa which ,
479and returns the actual resource limit in the 4th reference parameter.
480.Pp
481The
482.Fn procstat_getumask
483function gets a pointer to the
484.Vt procstat
485structure, a pointer to
486.Vt kinfo_proc
487structure, and returns the process umask in the 3rd reference parameter.
488.Pp
489The
490.Fn procstat_getvmmap
491function gets a pointer to the
492.Vt procstat
493structure initialized with one of the
494.Fn procstat_open_*
495functions, a pointer to
496.Vt kinfo_proc
497structure, and returns VM layout of the process as a dynamically allocated
498array of
499.Vt kinfo_vmentry
500structures.
501The caller is responsible to free the allocated memory with a subsequent
502.Fn procstat_freevmmap
503function call.
504.Pp
505The
506.Fn procstat_getadvlock
507function returns a dynamically allocated list of
508.Va struct advlock
509structures, providing a snapshot of the currently
510acquired advisory locks in the system.
511Both locally acquired POSIX (
512.Xr fcntl 2 )
513and BSD-style (
514.Xr flock 2 )
515locks are reported, as well as locks established by remote file
516system protocols.
517For each lock, unique identifiers for the locked file and its mount point
518are guaranteed to be provided.
519If a path for the locked file can be reconstructed, it is provided as well.
520The returned list must be freed with the
521.Fn procstat_freeadvlock
522function.
523.Pp
524The
525.Fn procstat_get_pipe_info ,
526.Fn procstat_get_pts_info ,
527.Fn procstat_get_sem_info ,
528.Fn procstat_get_shm_info ,
529.Fn procstat_get_socket_info
530and
531.Fn procstat_get_vnode_info
532functions are used to retrieve information about pipes, pseudo-terminals,
533semaphores, shared memory objects,
534sockets, and vnodes, respectively.
535Each of them have a similar interface API.
536The
537.Fa procstat
538argument is a pointer obtained from one of
539.Fn procstat_open_*
540functions.
541The
542.Ft filestat Fa fst
543argument is an element of STAILQ linked list as obtained from the
544.Fn procstat_getfiles
545function.
546The
547.Ft filestat
548structure contains a
549.Fa fs_type
550field that specifies a file type and a corresponding function to be
551called among the
552.Nm procstat_get_*_info
553function family.
554The actual object is returned in the 3rd reference parameter.
555The
556.Fa errbuf
557argument indicates an actual error message in case of failure.
558.Pp
559.Bl -tag -width 20n -compact -offset indent
560.It Li PS_FST_TYPE_FIFO
561.Nm procstat_get_vnode_info
562.It Li PS_FST_TYPE_VNODE
563.Nm procstat_get_vnode_info
564.It Li PS_FST_TYPE_SOCKET
565.Nm procstat_get_socket_info
566.It Li PS_FST_TYPE_PIPE
567.Nm procstat_get_pipe_info
568.It Li PS_FST_TYPE_PTS
569.Nm procstat_get_pts_info
570.It Li PS_FST_TYPE_SEM
571.Nm procstat_get_sem_info
572.It Li PS_FST_TYPE_SHM
573.Nm procstat_get_shm_info
574.El
575.Sh SEE ALSO
576.Xr fstat 1 ,
577.Xr fuser 1 ,
578.Xr pipe 2 ,
579.Xr shm_open 2 ,
580.Xr socket 2 ,
581.Xr elf 3 ,
582.Xr kvm 3 ,
583.Xr queue 3 ,
584.Xr sem_open 3 ,
585.Xr sysctl 3 ,
586.Xr pts 4 ,
587.Xr core 5 ,
588.Xr vnode 9
589.Sh HISTORY
590The
591.Nm libprocstat
592library appeared in
593.Fx 9.0 .
594.Sh AUTHORS
595.An -nosplit
596The
597.Nm libprocstat
598library was written by
599.An Stanislav Sedov Aq Mt stas@FreeBSD.org .
600.Pp
601This manual page was written by
602.An Sergey Kandaurov Aq Mt pluknet@FreeBSD.org .
603