podman-top: use containers/psgo

Use github.com/containers/psgo instead of execing `ps (1)`.  The psgo
library enables a much more flexible interface with respect to which
data to be printed (e.g., capabilities, seccomp mode, PID, PCPU, etc.)
while the output can be parsed reliably.  The library does not use
ps (1) but parses /proc and /dev instead.  To list the processes of a
given container, psgo will join the mount namespace of the given
container and extract all data from there.

Notice that this commit breaks compatibility with docker-top.

Signed-off-by: Valentin Rothberg <vrothberg@suse.com>

Closes: #1113
Approved by: rhatdan

1 files changed, 314 insertions, 0 deletions

diff --git a/vendor/github.com/containers/psgo/ps/status.go b/vendor/github.com/containers/psgo/ps/status.go
new file mode 100644
index 000000000..7f496bc48
--- /dev/null
+++ b/vendor/github.com/containers/psgo/ps/status.go
@@ -0,0 +1,314 @@
+package ps
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/pkg/errors"
+)
+
+// status is a direct translation of a `/proc/[pid]/status`, wich provides much
+// of the information in /proc/[pid]/stat and /proc/[pid]/statm in a format
+// that's easier for humans to parse.
+type status struct {
+	// Name: Command run by this process.
+	name string
+	// Umask: Process umask, expressed in octal with a leading  zero;  see
+	// umask(2). (Since Linux 4.7.)
+	umask string
+	// State:  Current  state  of the process.  One of "R (running)", "S
+	// (sleeping)", "D (disk sleep)", "T (stopped)", "T (tracing stop)", "Z
+	// (zombie)", or "X (dead)".
+	state string
+	// Tgid: Thread group ID (i.e., Process ID).
+	tgid string
+	// Ngid: NUMA group ID (0 if none; since Linux 3.13).
+	ngid string
+	// Pid: Thread ID (see gettid(2)).
+	pid string
+	// PPid: PID of parent process.
+	pPid string
+	// TracerPid: PID of process tracing this process (0 if not being traced).
+	tracerPid string
+	// Uids: Real, effective, saved set, and filesystem.
+	uids []string
+	// Gids: Real, effective, saved set, and filesystem.
+	gids []string
+	// FDSize: Number of file descriptor slots currently allocated.
+	fdSize string
+	// Groups: Supplementary group list.
+	groups []string
+	// NStgid : Thread group ID (i.e., PID) in each of the PID namespaces
+	// of which [pid] is  a member.   The  leftmost  entry shows the value
+	// with respect to the PID namespace of the reading process, followed
+	// by the value in successively nested inner namespaces.  (Since Linux
+	// 4.1.)
+	nStgid string
+	// NSpid:  Thread ID in each of the PID namespaces of which [pid] is a
+	// member.  The fields are ordered as for NStgid.  (Since Linux 4.1.)
+	nSpid string
+	// NSpgid: Process group ID in each of the PID namespaces of which
+	// [pid] is a member.  The fields are ordered as for NStgid.  (Since
+	// Linux 4.1.)
+	nSpgid string
+	// NSsid:  descendant  namespace session ID hierarchy Session ID in
+	// each of the PID names- paces of which [pid] is a member.  The fields
+	// are ordered as for NStgid.  (Since  Linux 4.1.)
+	nSsid string
+	// VmPeak: Peak virtual memory size.
+	vmPeak string
+	// VmSize: Virtual memory size.
+	vmSize string
+	// VmLck: Locked memory size (see mlock(3)).
+	vmLCK string
+	// VmPin:  Pinned  memory  size  (since  Linux  3.2).  These are pages
+	// that can't be moved because something needs to directly access
+	// physical memory.
+	vmPin string
+	// VmHWM: Peak resident set size ("high water mark").
+	vmHWM string
+	// VmRSS: Resident set size.  Note that the value here is the sum of
+	// RssAnon, RssFile, and RssShmem.
+	vmRSS string
+	// RssAnon: Size of resident anonymous memory.  (since Linux 4.5).
+	rssAnon string
+	// RssFile: Size of resident file mappings.  (since Linux 4.5).
+	rssFile string
+	// RssShmem:  Size  of  resident  shared memory (includes System V
+	// shared memory, mappings from tmpfs(5), and shared anonymous
+	// mappings).  (since Linux 4.5).
+	rssShmem string
+	// VmData: Size of data segment.
+	vmData string
+	// VmStk: Size of stack segment.
+	vmStk string
+	// VmExe: Size of text segment.
+	vmExe string
+	// VmLib: Shared library code size.
+	vmLib string
+	// VmPTE: Page table entries size (since Linux 2.6.10).
+	vmPTE string
+	// VmPMD: Size of second-level page tables (since Linux 4.0).
+	vmPMD string
+	// VmSwap: Swapped-out virtual memory size by anonymous private pages;
+	// shmem swap usage is not included (since Linux 2.6.34).
+	vmSwap string
+	// HugetlbPages: Size of hugetlb memory portions.  (since Linux 4.4).
+	hugetlbPages string
+	// Threads: Number of threads in process containing this thread.
+	threads string
+	// SigQ: This field contains two slash-separated numbers that relate to
+	// queued signals for the real user ID of this process.  The first of
+	// these is the number of currently queued signals  for  this  real
+	// user ID, and the second is the resource limit on the number of
+	// queued signals for this process (see the  description  of
+	// RLIMIT_SIGPENDING  in  getr- limit(2)).
+	sigQ string
+	// SigPnd:  Number  of signals pending for thread and for (see pthreads(7)).
+	sigPnd string
+	// ShdPnd:  Number  of signals pending for process as a whole (see
+	// signal(7)).
+	shdPnd string
+	//  SigBlk: Mask indicating signals being  blocked (see signal(7)).
+	sigBlk string
+	//  SigIgn: Mask indicating signals being ignored (see signal(7)).
+	sigIgn string
+	//  SigCgt: Mask indicating signals being  blocked caught (see signal(7)).
+	sigCgt string
+	// CapInh:  Mask of capabilities enabled in inheritable sets (see
+	// capabilities(7)).
+	capInh string
+	// CapPrm:  Mask of capabilities enabled in permitted sets (see
+	// capabilities(7)).
+	capPrm string
+	// CapEff:  Mask of capabilities enabled in effective sets (see
+	// capabilities(7)).
+	capEff string
+	// CapBnd: Capability Bounding set (since Linux 2.6.26, see
+	// capabilities(7)).
+	capBnd string
+	// CapAmb: Ambient capability set (since Linux 4.3, see capabilities(7)).
+	capAmb string
+	// NoNewPrivs: Value of the no_new_privs bit (since Linux 4.10, see
+	// prctl(2)).
+	noNewPrivs string
+	// Seccomp: Seccomp mode of the process (since Linux 3.8, see
+	// seccomp(2)).  0  means  SEC- COMP_MODE_DISABLED;  1  means
+	// SECCOMP_MODE_STRICT;  2 means SECCOMP_MODE_FILTER.  This field is
+	// provided only if the kernel was built with the CONFIG_SECCOMP kernel
+	// configu- ration option enabled.
+	seccomp string
+	// Cpus_allowed:  Mask  of  CPUs  on  which  this process may run
+	// (since Linux 2.6.24, see cpuset(7)).
+	cpusAllowed string
+	// Cpus_allowed_list: Same as previous, but in "list  format"  (since
+	// Linux  2.6.26,  see cpuset(7)).
+	cpusAllowedList string
+	// Mems_allowed:  Mask  of  memory  nodes allowed to this process
+	// (since Linux 2.6.24, see cpuset(7)).
+	memsAllowed string
+	// Mems_allowed_list: Same as previous, but in "list  format"  (since
+	// Linux  2.6.26,  see cpuset(7)).
+	memsAllowedList string
+	// voluntaryCtxtSwitches:  Number of voluntary context switches
+	// (since Linux 2.6.23).
+	voluntaryCtxtSwitches string
+	// nonvoluntaryCtxtSwitches:  Number of involuntary context switches
+	// (since Linux 2.6.23).
+	nonvoluntaryCtxtSwitches string
+}
+
+// readStatus is used for mocking in unit tests.
+var readStatus = func(path string) ([]string, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			err = errNoSuchPID
+		}
+		return nil, err
+	}
+	lines := []string{}
+	scanner := bufio.NewScanner(f)
+	for scanner.Scan() {
+		lines = append(lines, scanner.Text())
+	}
+	return lines, nil
+}
+
+// parseStatus parses the /proc/$pid/status file and returns a *status.
+func parseStatus(path string) (*status, error) {
+	lines, err := readStatus(path)
+	if err != nil {
+		return nil, err
+	}
+
+	s := status{}
+	errUnexpectedInput := errors.New(fmt.Sprintf("unexpected input from %s", path))
+	for _, line := range lines {
+		fields := strings.Fields(line)
+		if len(fields) < 2 {
+			continue
+		}
+
+		switch fields[0] {
+		case "Name:":
+			s.name = fields[1]
+		case "Umask:":
+			s.umask = fields[1]
+		case "State:":
+			s.state = fields[1]
+		case "Tgid:":
+			s.tgid = fields[1]
+		case "Ngid:":
+			s.ngid = fields[1]
+		case "Pid:":
+			s.pid = fields[1]
+		case "PPid:":
+			s.pPid = fields[1]
+		case "TracerPid:":
+			s.tracerPid = fields[1]
+		case "Uid:":
+			if len(fields) != 5 {
+				return nil, errors.Wrap(errUnexpectedInput, line)
+			}
+			s.uids = []string{fields[1], fields[2], fields[3], fields[4]}
+		case "Gid:":
+			if len(fields) != 5 {
+				return nil, errors.Wrap(errUnexpectedInput, line)
+			}
+			s.gids = []string{fields[1], fields[2], fields[3], fields[4]}
+		case "FDSize:":
+			s.fdSize = fields[1]
+		case "Groups:":
+			for _, g := range fields[1:] {
+				s.groups = append(s.groups, g)
+			}
+		case "NStgid:":
+			s.nStgid = fields[1]
+		case "NSpid:":
+			s.nSpid = fields[1]
+		case "NSpgid:":
+			s.nSpgid = fields[1]
+		case "NSsid:":
+			s.nSsid = fields[1]
+		case "VmPeak:":
+			s.vmPeak = fields[1]
+		case "VmSize:":
+			s.vmSize = fields[1]
+		case "VmLck:":
+			s.vmLCK = fields[1]
+		case "VmPin:":
+			s.vmPin = fields[1]
+		case "VmHWM:":
+			s.vmHWM = fields[1]
+		case "VmRSS:":
+			s.vmRSS = fields[1]
+		case "RssAnon:":
+			s.rssAnon = fields[1]
+		case "RssFile:":
+			s.rssFile = fields[1]
+		case "RssShmem:":
+			s.rssShmem = fields[1]
+		case "VmData:":
+			s.vmData = fields[1]
+		case "VmStk:":
+			s.vmStk = fields[1]
+		case "VmExe:":
+			s.vmExe = fields[1]
+		case "VmLib:":
+			s.vmLib = fields[1]
+		case "VmPTE:":
+			s.vmPTE = fields[1]
+		case "VmPMD:":
+			s.vmPMD = fields[1]
+		case "VmSwap:":
+			s.vmSwap = fields[1]
+		case "HugetlbPages:":
+			s.hugetlbPages = fields[1]
+		case "Threads:":
+			s.threads = fields[1]
+		case "SigQ:":
+			s.sigQ = fields[1]
+		case "SigPnd:":
+			s.sigPnd = fields[1]
+		case "ShdPnd:":
+			s.shdPnd = fields[1]
+		case "SigBlk:":
+			s.sigBlk = fields[1]
+		case "SigIgn:":
+			s.sigIgn = fields[1]
+		case "SigCgt:":
+			s.sigCgt = fields[1]
+		case "CapInh:":
+			s.capInh = fields[1]
+		case "CapPrm:":
+			s.capPrm = fields[1]
+		case "CapEff:":
+			s.capEff = fields[1]
+		case "CapBnd:":
+			s.capBnd = fields[1]
+		case "CapAmb:":
+			s.capAmb = fields[1]
+		case "NoNewPrivs:":
+			s.noNewPrivs = fields[1]
+		case "Seccomp:":
+			s.seccomp = fields[1]
+		case "Cpus_allowed:":
+			s.cpusAllowed = fields[1]
+		case "Cpus_allowed_list:":
+			s.cpusAllowedList = fields[1]
+		case "Mems_allowed:":
+			s.memsAllowed = fields[1]
+		case "Mems_allowed_list:":
+			s.memsAllowedList = fields[1]
+		case "voluntary_ctxt_switches:":
+			s.voluntaryCtxtSwitches = fields[1]
+		case "nonvoluntary_ctxt_switches:":
+			s.nonvoluntaryCtxtSwitches = fields[1]
+		}
+	}
+
+	return &s, nil
+}