Hello,
Although a patch like this was submitted before, this one is more "focused". It
may be useful for those moving from MFS who use this option to pre-populate an
MFS mount with a collection of files.
This will refuse to work if the path specified for -P is not a directory.
If the copy is unsuccessful, unmount and inform the user.
A few questions on this though:
1. Is there a better way than executing pax, to copy all the files in a
directory?
2. The do_exec() function was sort of copied from sbin/newfs/newfs.c. It
doesn't feel like the best way of handling this, but some research suggests it
is better than calling system() due to security issues, one that springs to
mind is a malformed input directory to the -P option. Is there a simple way to
sanitise the input for use with system()?
3. I noticed a pattern of functions that have about 2-3 lines of code in them.
Is it best to keep things that way, or is it best to merge them into a single
function (eg. copy_dir() merged into the mount_tmpfs() function)?
4. Are variable declarations to be at the beginning of a function block, or the
beginning of the immediate block? I feel limiting scope is a good idea, but
would like some feedback on this as I cannot see anything in style(9).
5. Is mount_tmpfs.h really necessary, given nothing in the tree seems to use
anything related to the mount_tmpfs() function which is internal to the
mount_tmpfs binary?
---------
Index: sbin/mount_tmpfs/mount_tmpfs.8
===================================================================
RCS file: /cvs/src/sbin/mount_tmpfs/mount_tmpfs.8,v
retrieving revision 1.4
diff -u -p -r1.4 mount_tmpfs.8
--- sbin/mount_tmpfs/mount_tmpfs.8 16 Nov 2014 02:22:10 -0000 1.4
+++ sbin/mount_tmpfs/mount_tmpfs.8 13 Sep 2015 13:03:34 -0000
@@ -41,6 +41,7 @@
.Op Fl m Ar mode
.Op Fl n Ar nodes
.Op Fl o Ar options
+.Op Fl P Ar directory
.Op Fl s Ar size
.Op Fl u Ar user
.Ar tmpfs
@@ -80,6 +81,8 @@ flag followed by a comma-separated strin
See the
.Xr mount 8
man page for possible options and their meanings.
+.It Fl P Ar directory
+Populate the created tmpfs file system with the contents of the directory.
.It Fl s Ar size
Specifies the total file system size in bytes.
If zero is given (the default), the available amount of memory (including
@@ -136,6 +139,10 @@ and
.Ox 5.5 .
.Sh CAVEATS
The update of mount options (through mount -u) is currently not supported.
+The
+.Fl P
+option will produce an error if the mount is read-only, or if the files
+cannot be copied from the specified template directory.
.Sh BUGS
File system meta-data is not pageable.
If there is not enough main memory to hold this information, the system may
Index: sbin/mount_tmpfs/mount_tmpfs.c
===================================================================
RCS file: /cvs/src/sbin/mount_tmpfs/mount_tmpfs.c,v
retrieving revision 1.5
diff -u -p -r1.5 mount_tmpfs.c
--- sbin/mount_tmpfs/mount_tmpfs.c 16 Jan 2015 06:39:59 -0000 1.5
+++ sbin/mount_tmpfs/mount_tmpfs.c 13 Sep 2015 13:03:34 -0000
@@ -34,6 +34,7 @@
#include <sys/types.h>
#include <sys/mount.h>
#include <sys/stat.h>
+#include <sys/wait.h>
#include <ctype.h>
#include <err.h>
@@ -41,6 +42,7 @@
#include <grp.h>
#include <mntopts.h>
#include <pwd.h>
+#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
@@ -68,12 +70,15 @@ static int a_num(const char *, const cha
static mode_t a_mask(const char *);
static void pathadj(const char *, char *);
+static int do_exec(const char *, const char *, char *const[]);
+static int copy_dir(char *, char *);
+
/* --------------------------------------------------------------------- */
void
mount_tmpfs_parseargs(int argc, char *argv[],
struct tmpfs_args *args, int *mntflags,
- char *canon_dev, char *canon_dir)
+ char *canon_dev, char *canon_dir, char *pop_dir)
{
int gidset, modeset, uidset; /* Ought to be 'bool'. */
int ch;
@@ -95,7 +100,7 @@ mount_tmpfs_parseargs(int argc, char *ar
modeset = 0; mode = 0;
optind = optreset = 1;
- while ((ch = getopt(argc, argv, "g:m:n:o:s:u:")) != -1 ) {
+ while ((ch = getopt(argc, argv, "P:g:m:n:o:s:u:")) != -1 ) {
switch (ch) {
case 'g':
gid = a_gid(optarg);
@@ -131,6 +136,10 @@ mount_tmpfs_parseargs(int argc, char *ar
uidset = 1;
break;
+ case 'P':
+ strlcpy(pop_dir, optarg, PATH_MAX);
+ break;
+
case '?':
default:
usage();
@@ -161,7 +170,8 @@ usage(void)
extern char *__progname;
(void)fprintf(stderr,
"usage: %s [-g group] [-m mode] [-n nodes] [-o options] [-s size]\n"
- " [-u user] tmpfs mount_point\n", __progname);
+ " [-P directory] [-u user] tmpfs mount_point\n",
+ __progname);
exit(1);
}
@@ -172,14 +182,33 @@ mount_tmpfs(int argc, char *argv[])
{
struct tmpfs_args args;
char canon_dev[PATH_MAX], canon_dir[PATH_MAX];
+ char pop_dir[PATH_MAX] = {0};
int mntflags;
+ int ret;
+ struct stat st;
mount_tmpfs_parseargs(argc, argv, &args, &mntflags,
- canon_dev, canon_dir);
+ canon_dev, canon_dir, pop_dir);
+
+ if(pop_dir[0] != '\0') {
+ if (stat(pop_dir, &st) != 0)
+ err(1, "cannot stat %s", pop_dir);
+ if (!S_ISDIR(st.st_mode))
+ errx(1, "%s: not a directory", pop_dir);
+ }
if (mount(MOUNT_TMPFS, canon_dir, mntflags, &args) == -1)
err(EXIT_FAILURE, "tmpfs on %s", canon_dir);
+ if (pop_dir[0] != '\0') {
+ ret = copy_dir(pop_dir, canon_dir);
+ if (ret != 0) {
+ if (unmount(canon_dir, 0) != 0)
+ warn("unmount %s", canon_dir);
+ errx(1, "copy %s to %s failed", pop_dir, canon_dir);
+ }
+ }
+
return EXIT_SUCCESS;
}
@@ -245,4 +274,55 @@ pathadj(const char *input, char *adjuste
warnx("\"%s\" is a non-resolved or relative path.", input);
warnx("using \"%s\" instead.", adjusted);
}
+}
+
+static int
+do_exec(const char *dir, const char *cmd, char *const argv[])
+{
+ pid_t pid;
+ int ret, status;
+ sig_t intsave, quitsave;
+
+ switch (pid = fork()) {
+ case -1:
+ err(1, "fork");
+ case 0:
+ if (dir != NULL && chdir(dir) != 0)
+ err(1, "chdir");
+ if (execv(cmd, argv) != 0)
+ err(1, "%s", cmd);
+ break;
+ default:
+ intsave = signal(SIGINT, SIG_IGN);
+ quitsave = signal(SIGQUIT, SIG_IGN);
+ for (;;) {
+ ret = waitpid(pid, &status, 0);
+ if (ret == -1)
+ err(11, "waitpid");
+ if (WIFEXITED(status)) {
+ status = WEXITSTATUS(status);
+ if (status != 0)
+ warnx("%s: exited", cmd);
+ break;
+ } else if (WIFSIGNALED(status)) {
+ warnx("%s: %s", cmd,
+ strsignal(WTERMSIG(status)));
+ status = 1;
+ break;
+ }
+ }
+ signal(SIGINT, intsave);
+ signal(SIGQUIT, quitsave);
+ return (status);
+ }
+ /* NOTREACHED */
+ return (-1);
+}
+
+static int
+copy_dir(char *src, char *dst)
+{
+ char *const argv[] = { "pax", "-rw", "-pe", ".", dst, NULL } ;
+
+ return do_exec(src, "/bin/pax", argv);
}
Index: sbin/mount_tmpfs/mount_tmpfs.h
===================================================================
RCS file: /cvs/src/sbin/mount_tmpfs/mount_tmpfs.h,v
retrieving revision 1.2
diff -u -p -r1.2 mount_tmpfs.h
--- sbin/mount_tmpfs/mount_tmpfs.h 3 Jun 2013 10:37:02 -0000 1.2
+++ sbin/mount_tmpfs/mount_tmpfs.h 13 Sep 2015 13:03:34 -0000
@@ -31,6 +31,6 @@
int mount_tmpfs(int, char **);
void mount_tmpfs_parseargs(int, char **, struct tmpfs_args *, int *,
- char *, char *);
+ char *, char *, char *);
#endif /* _SBIN_MOUNT_TMPFS_MOUNT_TMPFS_H_ */
