From 6cb1c31d3f9e575688ace95206898c7fff0c88f9 Mon Sep 17 00:00:00 2001 From: baude Date: Mon, 26 Feb 2018 09:08:19 -0600 Subject: Restrict top output to container's pids only Due to the way ps arguments work, it was possible to display pids that dont below to the container in top output. We now filter pids that dont belong to the container out of the output. This also means the pid column must be present in the output or we throw an error. This resolves issue #391 Signed-off-by: baude Closes: #400 Approved by: rhatdan --- libpod/container_top.go | 54 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 52 insertions(+), 2 deletions(-) (limited to 'libpod') diff --git a/libpod/container_top.go b/libpod/container_top.go index 3eb484acd..241e3a3e7 100644 --- a/libpod/container_top.go +++ b/libpod/container_top.go @@ -38,7 +38,7 @@ func (c *Container) getContainerPids() ([]string, error) { } // GetContainerPidInformation calls ps with the appropriate options and returns -// the results as a string +// the results as a string and the container's PIDs as a []string func (c *Container) GetContainerPidInformation(args []string) ([]string, error) { if !c.locked { c.lock.Lock() @@ -57,5 +57,55 @@ func (c *Container) GetContainerPidInformation(args []string) ([]string, error) if err != nil { return []string{}, errors.Wrapf(err, "unable to obtain information about pids") } - return strings.Split(results, "\n"), nil + + filteredOutput, err := filterPids(results, pids) + if err != nil { + return []string{}, err + } + return filteredOutput, nil +} + +func filterPids(psOutput string, pids []string) ([]string, error) { + var output []string + results := strings.Split(psOutput, "\n") + // The headers are in the first line of the results + headers := fieldsASCII(results[0]) + // We need to make sure PID in headers, so that we can filter + // Pids that don't belong. + + // append the headers back in + output = append(output, results[0]) + + pidIndex := -1 + for i, header := range headers { + if header == "PID" { + pidIndex = i + } + } + if pidIndex == -1 { + return []string{}, errors.Errorf("unable to find PID field in ps output. try a different set of ps arguments") + } + for _, l := range results[1:] { + if l == "" { + continue + } + cols := fieldsASCII(l) + pid := cols[pidIndex] + if StringInSlice(pid, pids) { + output = append(output, l) + } + } + return output, nil +} + +// Detects ascii whitespaces +func fieldsASCII(s string) []string { + fn := func(r rune) bool { + switch r { + case '\t', '\n', '\f', '\r', ' ': + return true + } + return false + } + return strings.FieldsFunc(s, fn) } -- cgit v1.2.3-54-g00ecf