xref: /freebsd/lib/libprocstat/libprocstat.3 (revision 2008043f386721d58158e37e0d7e50df8095942d)
1.\" Copyright (c) 2011 Sergey Kandaurov <pluknet@FreeBSD.org>
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25.Dd April 3, 2022
26.Dt LIBPROCSTAT 3
27.Os
28.Sh NAME
29.Nm procstat_close ,
30.Nm procstat_freeadvlock ,
31.Nm procstat_freeargv ,
32.Nm procstat_freeauxv ,
33.Nm procstat_freeenvv ,
34.Nm procstat_freefiles ,
35.Nm procstat_freegroups ,
36.Nm procstat_freekstack ,
37.Nm procstat_freeprocs ,
38.Nm procstat_freeptlwpinfo ,
39.Nm procstat_freevmmap ,
40.Nm procstat_get_pipe_info ,
41.Nm procstat_get_pts_info ,
42.Nm procstat_get_sem_info ,
43.Nm procstat_get_shm_info ,
44.Nm procstat_get_socket_info ,
45.Nm procstat_get_vnode_info ,
46.Nm procstat_getadvlock ,
47.Nm procstat_getargv ,
48.Nm procstat_getauxv ,
49.Nm procstat_getenvv ,
50.Nm procstat_getfiles ,
51.Nm procstat_getgroups ,
52.Nm procstat_getkstack ,
53.Nm procstat_getosrel ,
54.Nm procstat_getpathname ,
55.Nm procstat_getprocs ,
56.Nm procstat_getptlwpinfo ,
57.Nm procstat_getrlimit ,
58.Nm procstat_getumask ,
59.Nm procstat_getvmmap ,
60.Nm procstat_open_core ,
61.Nm procstat_open_kvm ,
62.Nm procstat_open_sysctl
63.Nd library interface for file and process information retrieval
64.Sh LIBRARY
65.Lb libprocstat
66.Sh SYNOPSIS
67.In sys/param.h
68.In sys/queue.h
69.In sys/socket.h
70.In libprocstat.h
71.Ft void
72.Fn procstat_close "struct procstat *procstat"
73.Ft void
74.Fn procstat_freeadvlock "struct procstat *procstat" "struct advlock_list *list"
75.Ft void
76.Fo procstat_freeargv
77.Fa "struct procstat *procstat"
78.Fc
79.Ft void
80.Fo procstat_freeauxv
81.Fa "struct procstat *procstat"
82.Fa "Elf_Auxinfo *auxv"
83.Fc
84.Ft void
85.Fo procstat_freeenvv
86.Fa "struct procstat *procstat"
87.Fc
88.Ft void
89.Fo procstat_freefiles
90.Fa "struct procstat *procstat"
91.Fa "struct filestat_list *head"
92.Fc
93.Ft void
94.Fo procstat_freegroups
95.Fa "struct procstat *procstat"
96.Fa "gid_t *groups"
97.Fc
98.Ft void
99.Fo procstat_freekstack
100.Fa "struct procstat *procstat"
101.Fa "struct kinfo_kstack *kkstp"
102.Fc
103.Ft void
104.Fn procstat_freeprocs "struct procstat *procstat" "struct kinfo_proc *p"
105.Ft void
106.Fo procstat_freevmmap
107.Fa "struct procstat *procstat"
108.Fa "struct kinfo_vmentry *vmmap"
109.Fc
110.Ft void
111.Fo procstat_freeptlwpinfo
112.Fa "struct procstat *procstat"
113.Fa "struct ptrace_lwpinfo *pl"
114.Fc
115.Ft int
116.Fo procstat_get_pipe_info
117.Fa "struct procstat *procstat"
118.Fa "struct filestat *fst"
119.Fa "struct pipestat *pipe"
120.Fa "char *errbuf"
121.Fc
122.Ft int
123.Fo procstat_get_pts_info
124.Fa "struct procstat *procstat"
125.Fa "struct filestat *fst"
126.Fa "struct ptsstat *pts"
127.Fa "char *errbuf"
128.Fc
129.Ft int
130.Fo procstat_get_sem_info
131.Fa "struct procstat *procstat"
132.Fa "struct filestat *fst"
133.Fa "struct semstat *sem"
134.Fa "char *errbuf"
135.Fc
136.Ft int
137.Fo procstat_get_shm_info
138.Fa "struct procstat *procstat"
139.Fa "struct filestat *fst"
140.Fa "struct shmstat *shm"
141.Fa "char *errbuf"
142.Fc
143.Ft int
144.Fo procstat_get_socket_info
145.Fa "struct procstat *procstat"
146.Fa "struct filestat *fst"
147.Fa "struct sockstat *sock"
148.Fa "char *errbuf"
149.Fc
150.Ft int
151.Fo procstat_get_vnode_info
152.Fa "struct procstat *procstat"
153.Fa "struct filestat *fst"
154.Fa "struct vnstat *vn"
155.Fa "char *errbuf"
156.Fc
157.Ft "struct advlock_list *"
158.Fo procstat_getadvlock
159.Fa "struct procstat *procstat"
160.Fc
161.Ft "char **"
162.Fo procstat_getargv
163.Fa "struct procstat *procstat"
164.Fa "const struct kinfo_proc *kp"
165.Fa "size_t nchr"
166.Fc
167.Ft "Elf_Auxinfo *"
168.Fo procstat_getauxv
169.Fa "struct procstat *procstat"
170.Fa "struct kinfo_proc *kp"
171.Fa "unsigned int *count"
172.Fc
173.Ft "char **"
174.Fo procstat_getenvv
175.Fa "struct procstat *procstat"
176.Fa "const struct kinfo_proc *kp"
177.Fa "size_t nchr"
178.Fc
179.Ft "struct filestat_list *"
180.Fo procstat_getfiles
181.Fa "struct procstat *procstat"
182.Fa "struct kinfo_proc *kp"
183.Fa "int mmapped"
184.Fc
185.Ft "gid_t *"
186.Fo procstat_getgroups
187.Fa "struct procstat *procstat"
188.Fa "struct kinfo_proc *kp"
189.Fa "unsigned int *count"
190.Fc
191.Ft "struct kinfo_kstack *"
192.Fo procstat_getkstack
193.Fa "struct procstat *procstat"
194.Fa "struct kinfo_proc *kp"
195.Fa "unsigned int *count"
196.Fc
197.Ft int
198.Fo procstat_getosrel
199.Fa "struct procstat *procstat"
200.Fa "struct kinfo_proc *kp"
201.Fa "int *osrelp"
202.Fc
203.Ft "int"
204.Fo procstat_getpathname
205.Fa "struct procstat *procstat"
206.Fa "struct kinfo_proc *kp"
207.Fa "char *pathname"
208.Fa "size_t maxlen"
209.Fc
210.Ft "struct kinfo_proc *"
211.Fo procstat_getprocs
212.Fa "struct procstat *procstat"
213.Fa "int what"
214.Fa "int arg"
215.Fa "unsigned int *count"
216.Fc
217.Ft "struct ptrace_lwpinfo *"
218.Fo procstat_getptlwpinfo
219.Fa "struct procstat *procstat"
220.Fa "unsigned int *count"
221.Fc
222.Ft "int"
223.Fo procstat_getrlimit
224.Fa "struct procstat *procstat"
225.Fa "struct kinfo_proc *kp"
226.Fa "int which"
227.Fa "struct rlimit* rlimit"
228.Fc
229.Ft "int"
230.Fo procstat_getumask
231.Fa "struct procstat *procstat"
232.Fa "struct kinfo_proc *kp"
233.Fa "unsigned short *maskp"
234.Fc
235.Ft "struct kinfo_vmentry *"
236.Fo procstat_getvmmap
237.Fa "struct procstat *procstat"
238.Fa "struct kinfo_proc *kp"
239.Fa "unsigned int *count"
240.Fc
241.Ft "struct procstat *"
242.Fn procstat_open_core "const char *filename"
243.Ft "struct procstat *"
244.Fn procstat_open_kvm "const char *nlistf" "const char *memf"
245.Ft "struct procstat *"
246.Fn procstat_open_sysctl void
247.Sh DESCRIPTION
248The
249.Nm libprocstat
250library contains the API for runtime file and process information
251retrieval from the running kernel via the
252.Xr sysctl 3
253library backend, and for post-mortem analysis via the
254.Xr kvm 3
255library backend, or from the process
256.Xr core 5
257file, searching for statistics in special
258.Xr elf 3
259note sections.
260.Pp
261The
262.Fn procstat_open_kvm
263and
264.Fn procstat_open_sysctl
265functions use the
266.Xr kvm 3
267or
268.Xr sysctl 3
269library routines, respectively, to access kernel state information
270used to retrieve processes and files states.
271The
272.Fn procstat_open_core
273uses
274.Xr elf 3
275routines to access statistics stored as a set of notes in a process
276.Xr core 5
277file, written by the kernel at the moment of the process abnormal termination.
278The
279.Fa filename
280argument is the process core file name.
281The
282.Fa nlistf
283argument is the executable image of the kernel being examined.
284If this argument is
285.Dv NULL ,
286the currently running kernel is assumed.
287The
288.Fa memf
289argument is the kernel memory device file.
290If this argument is
291.Dv NULL ,
292then
293.Pa /dev/mem
294is assumed.
295See
296.Xr kvm_open 3
297for more details.
298The functions dynamically allocate and return a
299.Vt procstat
300structure pointer used in the rest of the
301.Nm libprocstat
302library routines until the corresponding
303.Fn procstat_close
304call that cleans up the resources allocated by the
305.Fn procstat_open_*
306functions.
307.Pp
308The
309.Fn procstat_getprocs
310function gets a pointer to the
311.Vt procstat
312structure from one of the
313.Fn procstat_open_*
314functions and returns a dynamically allocated (sub-)set of active processes
315in the kernel filled in to array of
316.Vt kinfo_proc
317structures.
318The
319.Fa what
320and
321.Fa arg
322arguments constitute a filtering predicate as described in the
323.Xr kvm_getprocs 3
324function.
325The number of processes found is returned in the reference parameter
326.Fa cnt .
327The caller is responsible to free the allocated memory with a subsequent
328.Fn procstat_freeprocs
329function call.
330.Pp
331The
332.Fn procstat_getptlwpinfo
333function gets a pointer to the
334.Vt procstat
335structure from the
336.Fn procstat_open_core
337function and returns a dynamically allocated set of signals intercepted by a
338process in the process's core file.
339The number of processes found is returned in the reference parameter
340.Fa cnt .
341The caller is responsible to free the allocated memory with a subsequent
342.Fn procstat_freeptlwpinfo
343function call.
344.Pp
345The
346.Fn procstat_getargv
347function gets a pointer to the
348.Vt procstat
349structure from one of the
350.Fn procstat_open_*
351functions, a pointer to
352.Vt kinfo_proc
353structure from the array obtained from the
354.Fn procstat_getprocs
355function, and returns a null-terminated argument vector that corresponds to
356the command line arguments passed to the process.
357The
358.Fa nchr
359argument indicates the maximum number of characters, including null bytes,
360to use in building the strings.
361If this amount is exceeded, the string causing the overflow is truncated and
362the partial result is returned.
363This is handy for programs that print only a one line summary of a
364command and should not copy out large amounts of text only to ignore it.
365If
366.Fa nchr
367is zero, no limit is imposed and all argument strings are returned.
368The values of the returned argument vector refer the strings stored
369in the
370.Vt procstat
371internal buffer.
372A subsequent call of the function with the same
373.Vt procstat
374argument will reuse the buffer.
375To free the allocated memory
376.Fn procstat_freeargv
377function call can be used, or it will be released on
378.Fn procstat_close .
379.Pp
380The
381.Fn procstat_getenvv
382function is similar to
383.Fn procstat_getargv
384but returns the vector of environment strings.
385The caller may free the allocated memory with a subsequent
386.Fn procstat_freeenvv
387function call.
388.Pp
389The
390.Fn procstat_getauxv
391function gets a pointer to the
392.Vt procstat
393structure, a pointer to
394.Vt kinfo_proc
395structure, and returns the auxiliary vector as a dynamically allocated array of
396.Vt Elf_Auxinfo
397elements.
398The caller is responsible to free the allocated memory with a subsequent
399.Fn procstat_freeauxv
400function call.
401.Pp
402The
403.Fn procstat_getfiles
404function gets a pointer to the
405.Vt procstat
406structure initialized with one of the
407.Fn procstat_open_*
408functions, a pointer to
409.Vt kinfo_proc
410structure from the array obtained from the
411.Fn procstat_getprocs
412function, and returns a dynamically allocated linked list of filled in
413.Vt filestat_list
414structures using the STAILQ macros defined in
415.Xr queue 3 .
416The caller is responsible to free the allocated memory with a subsequent
417.Fn procstat_freefiles
418function call.
419.Pp
420The
421.Fn procstat_getgroups
422function gets a pointer to the
423.Vt procstat
424structure, a pointer to
425.Vt kinfo_proc
426structure, and returns the process groups as a dynamically allocated array of
427.Vt gid_t
428elements.
429The caller is responsible to free the allocated memory with a subsequent
430.Fn procstat_freegroups
431function call.
432.Pp
433The
434.Fn procstat_getkstack
435function gets a pointer to the
436.Vt procstat
437structure initialized with one of the
438.Fn procstat_open_*
439functions, a pointer to
440.Vt kinfo_proc
441structure, and returns kernel stacks of the process as a dynamically allocated
442array of
443.Vt kinfo_kstack
444structures.
445The caller is responsible to free the allocated memory with a subsequent
446.Fn procstat_freekstack
447function call.
448.Pp
449The
450.Fn procstat_getosrel
451function gets a pointer to the
452.Vt procstat
453structure, a pointer to
454.Vt kinfo_proc
455structure, and returns osrel date in the 3rd reference parameter.
456.Pp
457The
458.Fn procstat_getpathname
459function gets a pointer to the
460.Vt procstat
461structure, a pointer to
462.Vt kinfo_proc
463structure, and copies the path of the process executable to
464.Fa pathname
465buffer, limiting to
466.Fa maxlen
467characters.
468.Pp
469The
470.Fn procstat_getrlimit
471function gets a pointer to the
472.Vt procstat
473structure, a pointer to
474.Vt kinfo_proc
475structure, resource index
476.Fa which ,
477and returns the actual resource limit in the 4th reference parameter.
478.Pp
479The
480.Fn procstat_getumask
481function gets a pointer to the
482.Vt procstat
483structure, a pointer to
484.Vt kinfo_proc
485structure, and returns the process umask in the 3rd reference parameter.
486.Pp
487The
488.Fn procstat_getvmmap
489function gets a pointer to the
490.Vt procstat
491structure initialized with one of the
492.Fn procstat_open_*
493functions, a pointer to
494.Vt kinfo_proc
495structure, and returns VM layout of the process as a dynamically allocated
496array of
497.Vt kinfo_vmentry
498structures.
499The caller is responsible to free the allocated memory with a subsequent
500.Fn procstat_freevmmap
501function call.
502.Pp
503The
504.Fn procstat_getadvlock
505function returns a dynamically allocated list of
506.Va struct advlock
507structures, providing a snapshot of the currently
508acquired advisory locks in the system.
509Both locally acquired POSIX (
510.Xr fcntl 2 )
511and BSD-style (
512.Xr flock 2 )
513locks are reported, as well as locks established by remote file
514system protocols.
515For each lock, unique identifiers for the locked file and its mount point
516are guaranteed to be provided.
517If a path for the locked file can be reconstructed, it is provided as well.
518The returned list must be freed with the
519.Fn procstat_freeadvlock
520function.
521.Pp
522The
523.Fn procstat_get_pipe_info ,
524.Fn procstat_get_pts_info ,
525.Fn procstat_get_sem_info ,
526.Fn procstat_get_shm_info ,
527.Fn procstat_get_socket_info
528and
529.Fn procstat_get_vnode_info
530functions are used to retrieve information about pipes, pseudo-terminals,
531semaphores, shared memory objects,
532sockets, and vnodes, respectively.
533Each of them have a similar interface API.
534The
535.Fa procstat
536argument is a pointer obtained from one of
537.Fn procstat_open_*
538functions.
539The
540.Ft filestat Fa fst
541argument is an element of STAILQ linked list as obtained from the
542.Fn procstat_getfiles
543function.
544The
545.Ft filestat
546structure contains a
547.Fa fs_type
548field that specifies a file type and a corresponding function to be
549called among the
550.Nm procstat_get_*_info
551function family.
552The actual object is returned in the 3rd reference parameter.
553The
554.Fa errbuf
555argument indicates an actual error message in case of failure.
556.Pp
557.Bl -tag -width 20n -compact -offset indent
558.It Li PS_FST_TYPE_FIFO
559.Nm procstat_get_vnode_info
560.It Li PS_FST_TYPE_VNODE
561.Nm procstat_get_vnode_info
562.It Li PS_FST_TYPE_SOCKET
563.Nm procstat_get_socket_info
564.It Li PS_FST_TYPE_PIPE
565.Nm procstat_get_pipe_info
566.It Li PS_FST_TYPE_PTS
567.Nm procstat_get_pts_info
568.It Li PS_FST_TYPE_SEM
569.Nm procstat_get_sem_info
570.It Li PS_FST_TYPE_SHM
571.Nm procstat_get_shm_info
572.El
573.Sh SEE ALSO
574.Xr fstat 1 ,
575.Xr fuser 1 ,
576.Xr pipe 2 ,
577.Xr shm_open 2 ,
578.Xr socket 2 ,
579.Xr elf 3 ,
580.Xr kvm 3 ,
581.Xr queue 3 ,
582.Xr sem_open 3 ,
583.Xr sysctl 3 ,
584.Xr pts 4 ,
585.Xr core 5 ,
586.Xr vnode 9
587.Sh HISTORY
588The
589.Nm libprocstat
590library appeared in
591.Fx 9.0 .
592.Sh AUTHORS
593.An -nosplit
594The
595.Nm libprocstat
596library was written by
597.An Stanislav Sedov Aq Mt stas@FreeBSD.org .
598.Pp
599This manual page was written by
600.An Sergey Kandaurov Aq Mt pluknet@FreeBSD.org .
601