syz-manager: add prometheus metrics

* syz-manager: add prometheus metrics

Add prometheus metrics client to syz-manager.
Expose metrics on a new port defined in mgrconfig.

Allows for prometheus to scrape metrics from syz-manager.

* syz-manager: expose metrics endpoint in http server

.gitignore : remove local .img path

* mgrconfig: remove unnecessary config option

* syz-manager: update stats to use gaugefunc

added docs for prometheus exported metrics
added more gaugefunc metrics

Signed-off-by: Palash Oswal <oswalpalash@gmail.com>

* syz-manager: minor changes for CI tests

added periods to comments and renamed go variables

Signed-off-by: Palash Oswal <oswalpalash@gmail.com>

* syz-manager: re-position prometheus counter declaration

docs updated with PR comments

Signed-off-by: Palash Oswal <oswalpalash@gmail.com>

1 files changed, 52 insertions, 0 deletions

diff --git a/vendor/github.com/prometheus/procfs/internal/fs/fs.go b/vendor/github.com/prometheus/procfs/internal/fs/fs.go
new file mode 100644
index 000000000..c66a1cf80
--- /dev/null
+++ b/vendor/github.com/prometheus/procfs/internal/fs/fs.go
@@ -0,0 +1,52 @@
+// Copyright 2019 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package fs
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+const (
+	// DefaultProcMountPoint is the common mount point of the proc filesystem.
+	DefaultProcMountPoint = "/proc"
+
+	// DefaultSysMountPoint is the common mount point of the sys filesystem.
+	DefaultSysMountPoint = "/sys"
+)
+
+// FS represents a pseudo-filesystem, normally /proc or /sys, which provides an
+// interface to kernel data structures.
+type FS string
+
+// NewFS returns a new FS mounted under the given mountPoint. It will error
+// if the mount point can't be read.
+func NewFS(mountPoint string) (FS, error) {
+	info, err := os.Stat(mountPoint)
+	if err != nil {
+		return "", fmt.Errorf("could not read %s: %s", mountPoint, err)
+	}
+	if !info.IsDir() {
+		return "", fmt.Errorf("mount point %s is not a directory", mountPoint)
+	}
+
+	return FS(mountPoint), nil
+}
+
+// Path appends the given path elements to the filesystem path, adding separators
+// as necessary.
+func (fs FS) Path(p ...string) string {
+	return filepath.Join(append([]string{string(fs)}, p...)...)
+}