[PATCH] dump -U to specify dumpdates device

[Emmanuel Dreyfus <manu%netbsd.org@localhost>]

Hello

I have been running into situations where dump(8) could not figure the
device to use for updating /etc/dumpdates. It seems to be the case
when I give dump(8) a mount point associated with a NAME= label in /etc/fstab

It also obviously happens when we dump a filesystem subdirectory. Here
-u is forbidden because there cannot be an associated device, but we
could sill want to track backup status with a pseudoentry in /etc/dumpdates

I propose to add -U option to dump(8), which lets the administrator 
specify the device name in /etc/dumpdates. Example usages:
dump -a0uf /dump/data.dump -D NAME=data /data/
dump -a0uf /dump/data-abc.dump -D data-abc /data/a* /data/b* /data/c*

Here is the patch. Opinions?

Index: dump.8
===================================================================
RCS file: /cvsroot/src/sbin/dump/dump.8,v
retrieving revision 1.69
diff -U4 -r1.69 dump.8
--- dump.8      15 Jul 2018 06:14:13 -0000      1.69
+++ dump.8      20 Mar 2019 08:09:00 -0000
@@ -50,8 +50,9 @@
 .Op Fl l Ar timeout
 .Op Fl r Ar cachesize
 .Op Fl s Ar feet
 .Op Fl T Ar date
+.Op Fl U Ar dumpdev
 .Op Fl x Ar snap-backup
 .Ar files-to-dump
 .Nm
 .Op Fl W Li \&| Fl w
@@ -298,12 +299,24 @@
 The file
 .Pa /etc/dumpdates
 may be edited to change any of the fields,
 if necessary.
-If a list of files or subdirectories is being dumped
+If the
+.Fl T
+option is used or if a list of files or subdirectories is being dumped
 (as opposed to an entire file system), then
 .Fl u
 is ignored.
+.It Fl U Ar dumpdev
+Same as
+.Fl u
+but specifies the device in
+.Pa /etc/dumpdates
+as
+.Ar dumpdev .
+This option can be used with subdir dumps and with the
+.Fl T
+option.
 .It Fl W
 .Nm
 tells the operator what file systems need to be dumped.
 This information is gleaned from the files
--- dump.h      1 Mar 2019 16:42:11 -0000       1.56
+++ dump.h      20 Mar 2019 08:09:00 -0000
@@ -114,8 +114,9 @@
 const char *temp;      /* name of the file for doing rewrite of dumpdates */
 char   lastlevel;      /* dump level of previous dump */
 char   level;          /* dump level of this dump */
 int    uflag;          /* update flag */
+const char *dumpdev;   /* device name in dumpdates */
 int    eflag;          /* eject flag */
 int    lflag;          /* autoload flag */
 int    diskfd;         /* disk file descriptor */
 int    tapefd;         /* tape file descriptor */
--- itime.c     1 Mar 2019 16:42:11 -0000       1.21
+++ itime.c     20 Mar 2019 08:09:00 -0000
@@ -128,11 +128,11 @@
 getdumptime(void)
 {
        struct dumpdates *ddp;
        int i;
-       char *fname;
+       const char *fname;
 
-       fname = disk;
+       fname = dumpdev ? dumpdev : disk;
 #ifdef FDEBUG
        msg("Looking for name %s in dumpdates = %s for level = %c\n",
                fname, dumpdates, level);
 #endif
@@ -169,17 +169,17 @@
        FILE *df;
        struct dumpdates *dtwalk, *dtfound;
        int i;
        int fd;
-       char *fname;
+       const char *fname;
 
-       if(uflag == 0)
+       if(uflag == 0 && dumpdev == NULL)
                return;
        if ((df = fopen(dumpdates, "r+")) == NULL)
                quite(errno, "cannot rewrite %s", dumpdates);
        fd = fileno(df);
        (void) flock(fd, LOCK_EX);
-       fname = disk;
+       fname = dumpdev ? dumpdev : disk;
        free((char *)ddatev);
        ddatev = 0;
        nddates = 0;
        readdumptimes(df);
--- main.c      1 Mar 2019 16:42:11 -0000       1.74
+++ main.c      20 Mar 2019 08:09:00 -0000
@@ -132,9 +132,9 @@
                usage();
 
        obsolete(&argc, &argv);
        while ((ch = getopt(argc, argv,
-           "0123456789aB:b:cd:eFf:h:ik:l:L:nr:s:StT:uWwx:X")) != -1)
+           "0123456789aB:b:cd:eFf:h:ik:l:L:nr:s:StT:uU:Wwx:X")) != -1)
                switch (ch) {
                /* dump level */
                case '0': case '1': case '2': case '3': case '4':
                case '5': case '6': case '7': case '8': case '9':
@@ -244,8 +244,12 @@
                case 'u':               /* update /etc/dumpdates */
                        uflag = 1;
                        break;
 
+               case 'U':               /* dump device in /etc/dumpdates */
+                       dumpdev = optarg;
+                       break;
+
                case 'W':               /* what to do */
                case 'w':
                        lastdump(ch);
                        exit(X_FINOK);  /* do nothing else */



-- 
Emmanuel Dreyfus
manu%netbsd.org@localhost