Re: [linux-lvm] Linux 2.4.0-test12-pre7 LVM .9 vs .8final

[Luca Berra <bluca comedia it>]

On Mon, Dec 11, 2000 at 07:44:32AM +0100, Ulf Bartelt wrote:
> A set of lvm tools for multiple versions of the io protocol could help a
> lot...
> 
> Sure this can be faked using links, wrappers etc...

i am using this piece of junk for testing and switching back btw 0.8 and 0.9

L.

-- 
Luca Berra -- bluca comedia it
    Communication Media & Services S.r.l.

/*
A wrapper for Linux LVM user space tools
No Copyright 2000 Luca Berra <bluca vodka it>

This program is free software: you can do anything you want
with it, I don't give a damn.

By using this piece of crap you agree that I (Luca Berra)
cannot be held responsible for any damage that it may cause.

To build: cc -o lvm_wrapper lwm_wrapper.c /usr/lib/liblvm.a
To use: move all lvm tools in /sbin/lvm/<iop>, where iop is the iop
	version supported by the tools (eg: 6 for lvm 0.8, 10 for lvm 0.9)
	install lvm_wrapper in /sbin.
	create links to lvm_wrapper for any program in /sbin/lvm/<iop>
	(for i in /sbin/lvm/*/*;do ln -s lvm_wrapper /sbin/${i##*/};done)

I suppose that if the tools are using a shared library you have changed the
shared library name to something including a version number.
else add a putenv("LD_LIBRARY_PATH=....") or putenv("LD_PRELOAD=....")
before the execv.

*/

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <string.h>
#include <stdio.h>
#include <limits.h>

#define LVM_CMD_PREFIX "/sbin/lvm"
struct stat buf;
char prog[PATH_MAX];
int opt_d = 0;

int
main(int argc, char **argv)
{
	int ret = lvm_get_iop_version();
	char *cmd = strrchr(argv[0], '/');
	if (cmd == NULL) {
	    cmd = argv[0];
	} else {
	    cmd++;
	}

	if (ret < 0) {
		fprintf(stderr, "%s -- LVM driver/module not loaded?\n\n", cmd);
		exit(-1);
	}
        
	snprintf(prog, PATH_MAX, "%s/%d/%s", LVM_CMD_PREFIX, ret, cmd);

	if (stat(prog, &buf) < 0) {
		fprintf(stderr, "%s -- invalid i/o protocol version %d\n\n", cmd, ret);
		exit(-1);
	}

	execv(prog,argv);
}