Re: Maxium command line args?

[Forrest Aldrich]

At 09:28 AM 2/27/2001 -0500, Derek R. Price wrote:
> Forrest Aldrich wrote:
>
> > We have a series of scripts from quick.com.au that will assist us in
> > managing our DNS pools.  The author mentions that a patch may be required
> > in order to avoid command line argument limitations, especially in the case
> > of > 500 zones (which we have).
> >
> > I'm no FreeBSD-4.x (currently patched and updated) which has CVS
> > 1.11.  Does this problem still apply to version 1.11 of CVS?  If so, do you
> > have a patch that will run against this code (the one he has is older).
>
> I'm not sure exactly how you think DNS pool management and CVS are related,
> but most systems have a command line argument limitation.  It's system
> specific, but on my Linux system, the environment and the command line are
> allowed to total something like 4096 bytes.  This can't be fixed by patching
> the executable.
>
> Derek
>
> --
> Derek Price                      CVS Solutions Architect ( 
> http://CVSHome.org )
> mailto:address@hidden     OpenAvenue ( http://OpenAvenue.com )
> --
> Was today really necessary?
[ ... ]


They are related if you USE cvs to manage your DNS pools.

For info on what I'm talking about, here's a patch.  I just manually 
applied it to the latest /usr/src/contrib/cvs/src/commit.c file on FreeBSD 
and it's working.

The patch contains a preamble which will perhaps explain things better for 
you.  I'd appreciate any feedback or ideas about other ways to handle this 
problem.


_F

...............................

Subject:
        Pre-commit check failure due to too many args.
   Date:
        Tue, 8 Dec 1998 15:08:52 +1100 (EST)
   From:
        "Simon J. Gerraty" <address@hidden>
     To:
        address@hidden
    CC:
        address@hidden, address@hidden




Hi,

we use CVS to maintain our DNS data.  We also use a DNS regression
suite (see http://www.quick.com.au/help/dns.html) to do pre-commit
checks - very handy.

The above toolset includes facilities for generating PTR records.
If/when we re-configure said tool, it can cause a few hundred in-addr
zone files to change.

This typically causes the pre-commit checks to fail as the OS command
line length is exceeded when cvs attempts to run the regression suite
in that directory.

The patch below (to cvs-1.10) modifies precommit_proc() such that if
the pre-commit filter command begins with "xargs" or _PATH_XARGS, then
it is run using run_popen() rather than run_exec().

I'm submitting it here in its first cut form to see what others think
(of the idea - not the code :-)  It may be better forinstance to
always use run_popen() ? But for now this does the job.

--sjg

Index: commit.c
===================================================================
RCS file: /home/cvsroot/cvs/src/commit.c,v
retrieving revision 1.1.1.1
diff -c -b -r1.1.1.1 commit.c
*** commit.c    1998/12/08 01:08:38     1.1.1.1
--- commit.c    1998/12/08 03:16:36
***************
*** 1089,1100 ****
--- 1089,1104 ----
      void *closure;
  {
      struct logfile_info *li;
+     FILE *fp = closure;

      li = (struct logfile_info *) p->data;
      if (li->type == T_ADDED
        || li->type == T_MODIFIED
        || li->type == T_REMOVED)
      {
+           if (fp)
+                   fprintf(fp, "'%s'\n", p->key);
+           else
                    run_arg (p->key);
      }
      return (0);
***************
*** 1108,1113 ****
--- 1112,1119 ----
      char *repository;
      char *filter;
  {
+       int rc = -1;
+
      /* see if the filter is there, only if it's a full path */
      if (isabsolute (filter))
      {
***************
*** 1129,1138 ****
        free (s);
      }

      run_setup (filter);
      run_arg (repository);
      (void) walklist (saved_ulist, precommit_list_proc, NULL);
!     return (run_exec (RUN_TTY, RUN_TTY, RUN_TTY, RUN_NORMAL|RUN_REALLY));
  }

  /*
--- 1135,1188 ----
        free (s);
      }

+ #ifndef _PATH_XARGS
+ # define _PATH_XARGS "/usr/bin/xargs"
+ #endif
+     if (strncmp(filter, _PATH_XARGS, sizeof(_PATH_XARGS) - 1) == 0
+       || strncmp(filter, "xargs", 5) == 0) {
+           /*
+            * we expect many args, so don't try run_exec()
+            */
+           char *cmd = xmalloc(strlen(filter) + strlen(repository) + 4);
+           if (cmd) {
+                   FILE *fp;
+                   int status = -1;
+
+                   sprintf(cmd, "%s %s", filter, repository);
+
+                   if (fp = run_popen(cmd, "w")) {
+                           (void) walklist (saved_ulist, 
precommit_list_proc, fp);
+                           status = pclose(fp);
+                           if (status != -1) {
+                                   /*
+                                    * from run_exec()
+                                    */
+ #ifndef VMS /* status is return status */
+                                   if (WIFEXITED (status))
+                                           rc = WEXITSTATUS (status);
+                                   else if (WIFSIGNALED (status))
+                                   {
+                                           if (WTERMSIG (status) == SIGPIPE)
+                                                   error (1, 0, "broken 
pipe");
+                                           rc = 2;
+                                   }
+                                   else
+                                           rc = 1;
+ #else /* VMS */
+                                   rc = WEXITSTATUS (status);
+ #endif /* VMS */
+                           }
+                   }
+                   free(cmd);
+           }
+
+     } else {
            run_setup (filter);
            run_arg (repository);
            (void) walklist (saved_ulist, precommit_list_proc, NULL);
!           rc = run_exec (RUN_TTY, RUN_TTY, RUN_TTY, RUN_NORMAL|RUN_REALLY);
!     }
!     return rc;
  }

  /*