Vendor in latest github.com/projectatomic/buildah

This adds support for Dockerfile.in and fixes some limits
issues on docker build

Also adds support for podman build to read Dockerfile from stdin.

cat Dockerfile | podman build -f - .

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

Closes: #1209
Approved by: mheon

1 files changed, 273 insertions, 0 deletions

diff --git a/vendor/github.com/projectatomic/buildah/unshare/unshare.go b/vendor/github.com/projectatomic/buildah/unshare/unshare.go
new file mode 100644
index 000000000..ed2a97934
--- /dev/null
+++ b/vendor/github.com/projectatomic/buildah/unshare/unshare.go
@@ -0,0 +1,273 @@
+// +build linux
+
+package unshare
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"runtime"
+	"strconv"
+	"strings"
+	"syscall"
+
+	"github.com/containers/storage/pkg/reexec"
+	"github.com/opencontainers/runtime-spec/specs-go"
+	"github.com/pkg/errors"
+	"github.com/projectatomic/buildah/util"
+)
+
+// Cmd wraps an exec.Cmd created by the reexec package in unshare(), and
+// handles setting ID maps and other related settings by triggering
+// initialization code in the child.
+type Cmd struct {
+	*exec.Cmd
+	UnshareFlags               int
+	UseNewuidmap               bool
+	UidMappings                []specs.LinuxIDMapping
+	UseNewgidmap               bool
+	GidMappings                []specs.LinuxIDMapping
+	GidMappingsEnableSetgroups bool
+	Setsid                     bool
+	Setpgrp                    bool
+	Ctty                       *os.File
+	OOMScoreAdj                int
+	Hook                       func(pid int) error
+}
+
+// Command creates a new Cmd which can be customized.
+func Command(args ...string) *Cmd {
+	cmd := reexec.Command(args...)
+	return &Cmd{
+		Cmd: cmd,
+	}
+}
+
+func (c *Cmd) Start() error {
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	// Set an environment variable to tell the child to synchronize its startup.
+	if c.Env == nil {
+		c.Env = os.Environ()
+	}
+	c.Env = append(c.Env, fmt.Sprintf("_Buildah-unshare=%d", c.UnshareFlags))
+
+	// Create the pipe for reading the child's PID.
+	pidRead, pidWrite, err := os.Pipe()
+	if err != nil {
+		return errors.Wrapf(err, "error creating pid pipe")
+	}
+	c.Env = append(c.Env, fmt.Sprintf("_Buildah-pid-pipe=%d", len(c.ExtraFiles)+3))
+	c.ExtraFiles = append(c.ExtraFiles, pidWrite)
+
+	// Create the pipe for letting the child know to proceed.
+	continueRead, continueWrite, err := os.Pipe()
+	if err != nil {
+		pidRead.Close()
+		pidWrite.Close()
+		return errors.Wrapf(err, "error creating pid pipe")
+	}
+	c.Env = append(c.Env, fmt.Sprintf("_Buildah-continue-pipe=%d", len(c.ExtraFiles)+3))
+	c.ExtraFiles = append(c.ExtraFiles, continueRead)
+
+	// Pass along other instructions.
+	if c.Setsid {
+		c.Env = append(c.Env, "_Buildah-setsid=1")
+	}
+	if c.Setpgrp {
+		c.Env = append(c.Env, "_Buildah-setpgrp=1")
+	}
+	if c.Ctty != nil {
+		c.Env = append(c.Env, fmt.Sprintf("_Buildah-ctty=%d", len(c.ExtraFiles)+3))
+		c.ExtraFiles = append(c.ExtraFiles, c.Ctty)
+	}
+	if c.GidMappingsEnableSetgroups {
+		c.Env = append(c.Env, "_Buildah-allow-setgroups=1")
+	} else {
+		c.Env = append(c.Env, "_Buildah-allow-setgroups=0")
+	}
+
+	// Make sure we clean up our pipes.
+	defer func() {
+		if pidRead != nil {
+			pidRead.Close()
+		}
+		if pidWrite != nil {
+			pidWrite.Close()
+		}
+		if continueRead != nil {
+			continueRead.Close()
+		}
+		if continueWrite != nil {
+			continueWrite.Close()
+		}
+	}()
+
+	// Start the new process.
+	err = c.Cmd.Start()
+	if err != nil {
+		return err
+	}
+
+	// Close the ends of the pipes that the parent doesn't need.
+	continueRead.Close()
+	continueRead = nil
+	pidWrite.Close()
+	pidWrite = nil
+
+	// Read the child's PID from the pipe.
+	pidString := ""
+	b := new(bytes.Buffer)
+	io.Copy(b, pidRead)
+	pidString = b.String()
+	pid, err := strconv.Atoi(pidString)
+	if err != nil {
+		fmt.Fprintf(continueWrite, "error parsing PID %q: %v", pidString, err)
+		return errors.Wrapf(err, "error parsing PID %q", pidString)
+	}
+	pidString = fmt.Sprintf("%d", pid)
+
+	// If we created a new user namespace, set any specified mappings.
+	if c.UnshareFlags&syscall.CLONE_NEWUSER != 0 {
+		// Always set "setgroups".
+		setgroups, err := os.OpenFile(fmt.Sprintf("/proc/%s/setgroups", pidString), os.O_TRUNC|os.O_WRONLY, 0)
+		if err != nil {
+			fmt.Fprintf(continueWrite, "error opening setgroups: %v", err)
+			return errors.Wrapf(err, "error opening /proc/%s/setgroups", pidString)
+		}
+		defer setgroups.Close()
+		if c.GidMappingsEnableSetgroups {
+			if _, err := fmt.Fprintf(setgroups, "allow"); err != nil {
+				fmt.Fprintf(continueWrite, "error writing \"allow\" to setgroups: %v", err)
+				return errors.Wrapf(err, "error opening \"allow\" to /proc/%s/setgroups", pidString)
+			}
+		} else {
+			if _, err := fmt.Fprintf(setgroups, "deny"); err != nil {
+				fmt.Fprintf(continueWrite, "error writing \"deny\" to setgroups: %v", err)
+				return errors.Wrapf(err, "error writing \"deny\" to /proc/%s/setgroups", pidString)
+			}
+		}
+
+		if len(c.UidMappings) == 0 || len(c.GidMappings) == 0 {
+			uidmap, gidmap, err := util.GetHostIDMappings("")
+			if err != nil {
+				fmt.Fprintf(continueWrite, "error reading ID mappings in parent: %v", err)
+				return errors.Wrapf(err, "error reading ID mappings in parent")
+			}
+			if len(c.UidMappings) == 0 {
+				c.UidMappings = uidmap
+				for i := range c.UidMappings {
+					c.UidMappings[i].HostID = c.UidMappings[i].ContainerID
+				}
+			}
+			if len(c.GidMappings) == 0 {
+				c.GidMappings = gidmap
+				for i := range c.GidMappings {
+					c.GidMappings[i].HostID = c.GidMappings[i].ContainerID
+				}
+			}
+		}
+
+		if len(c.GidMappings) > 0 {
+			// Build the GID map, since writing to the proc file has to be done all at once.
+			g := new(bytes.Buffer)
+			for _, m := range c.GidMappings {
+				fmt.Fprintf(g, "%d %d %d\n", m.ContainerID, m.HostID, m.Size)
+			}
+			// Set the GID map.
+			if c.UseNewgidmap {
+				cmd := exec.Command("newgidmap", append([]string{pidString}, strings.Fields(strings.Replace(g.String(), "\n", " ", -1))...)...)
+				g.Reset()
+				cmd.Stdout = g
+				cmd.Stderr = g
+				err := cmd.Run()
+				if err != nil {
+					fmt.Fprintf(continueWrite, "error running newgidmap: %v: %s", err, g.String())
+					return errors.Wrapf(err, "error running newgidmap: %s", g.String())
+				}
+			} else {
+				gidmap, err := os.OpenFile(fmt.Sprintf("/proc/%s/gid_map", pidString), os.O_TRUNC|os.O_WRONLY, 0)
+				if err != nil {
+					fmt.Fprintf(continueWrite, "error opening /proc/%s/gid_map: %v", pidString, err)
+					return errors.Wrapf(err, "error opening /proc/%s/gid_map", pidString)
+				}
+				defer gidmap.Close()
+				if _, err := fmt.Fprintf(gidmap, "%s", g.String()); err != nil {
+					fmt.Fprintf(continueWrite, "error writing /proc/%s/gid_map: %v", pidString, err)
+					return errors.Wrapf(err, "error writing /proc/%s/gid_map", pidString)
+				}
+			}
+		}
+
+		if len(c.UidMappings) > 0 {
+			// Build the UID map, since writing to the proc file has to be done all at once.
+			u := new(bytes.Buffer)
+			for _, m := range c.UidMappings {
+				fmt.Fprintf(u, "%d %d %d\n", m.ContainerID, m.HostID, m.Size)
+			}
+			// Set the GID map.
+			if c.UseNewuidmap {
+				cmd := exec.Command("newuidmap", append([]string{pidString}, strings.Fields(strings.Replace(u.String(), "\n", " ", -1))...)...)
+				u.Reset()
+				cmd.Stdout = u
+				cmd.Stderr = u
+				err := cmd.Run()
+				if err != nil {
+					fmt.Fprintf(continueWrite, "error running newuidmap: %v: %s", err, u.String())
+					return errors.Wrapf(err, "error running newuidmap: %s", u.String())
+				}
+			} else {
+				uidmap, err := os.OpenFile(fmt.Sprintf("/proc/%s/uid_map", pidString), os.O_TRUNC|os.O_WRONLY, 0)
+				if err != nil {
+					fmt.Fprintf(continueWrite, "error opening /proc/%s/uid_map: %v", pidString, err)
+					return errors.Wrapf(err, "error opening /proc/%s/uid_map", pidString)
+				}
+				defer uidmap.Close()
+				if _, err := fmt.Fprintf(uidmap, "%s", u.String()); err != nil {
+					fmt.Fprintf(continueWrite, "error writing /proc/%s/uid_map: %v", pidString, err)
+					return errors.Wrapf(err, "error writing /proc/%s/uid_map", pidString)
+				}
+			}
+		}
+	}
+
+	// Adjust the process's OOM score.
+	oomScoreAdj, err := os.OpenFile(fmt.Sprintf("/proc/%s/oom_score_adj", pidString), os.O_TRUNC|os.O_WRONLY, 0)
+	if err != nil {
+		fmt.Fprintf(continueWrite, "error opening oom_score_adj: %v", err)
+		return errors.Wrapf(err, "error opening /proc/%s/oom_score_adj", pidString)
+	}
+	if _, err := fmt.Fprintf(oomScoreAdj, "%d\n", c.OOMScoreAdj); err != nil {
+		fmt.Fprintf(continueWrite, "error writing \"%d\" to oom_score_adj: %v", c.OOMScoreAdj, err)
+		return errors.Wrapf(err, "error writing \"%d\" to /proc/%s/oom_score_adj", c.OOMScoreAdj, pidString)
+	}
+	defer oomScoreAdj.Close()
+
+	// Run any additional setup that we want to do before the child starts running proper.
+	if c.Hook != nil {
+		if err = c.Hook(pid); err != nil {
+			fmt.Fprintf(continueWrite, "hook error: %v", err)
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (c *Cmd) Run() error {
+	if err := c.Start(); err != nil {
+		return err
+	}
+	return c.Wait()
+}
+
+func (c *Cmd) CombinedOutput() ([]byte, error) {
+	return nil, errors.New("unshare: CombinedOutput() not implemented")
+}
+
+func (c *Cmd) Output() ([]byte, error) {
+	return nil, errors.New("unshare: Output() not implemented")
+}