/*
	Allocate a uniq XID for a name (a vserver).
	A database file is maintained in /var/run/vctxalloc.
	The dynamic XID allocation of the kernel is not used anymore.

	vallocctx set name
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>
#include <sys/types.h>
#include <signal.h>
#include <sys/socket.h>
#include <sys/ioctl.h>

#include <vector>
#include <map>
#include <string>

using namespace std;

static const char *statefile = "/var/run/vctxalloc";
static const char *lockfile = "/var/run/vctxalloc.lock";

static void usage()
{
	fprintf (stderr,"vallocctx version %s\n",VERSION);
	fprintf (stderr,
		"\n"
		"vallocctx get name\n"
		);
}

static int vallocctx_find (vector<string> &tb, const char *name)
{
	int ret = -1;
	for (vector<string>::iterator it = tb.begin();
		it != tb.end(); it++){
		if (strcmp(it->c_str(),name)==0){
			ret = it - tb.begin();
			break;
		}
	}
	return ret;
}

static void vallocctx_read (vector<string> &tb)
{
	FILE *fin = fopen (statefile,"r");
	if (fin != NULL){
		char line[1000];
		while (fgets(line,sizeof(line)-1,fin)!=NULL){
			char *pt = strchr(line,'\n');
			if (pt != NULL) *pt = '\0';
			if (line[0] > ' '){
				tb.push_back(line);
			}
		}
		fclose (fin);
	}
}

static void vallocctx_write (vector<string> &tb)
{
	FILE *fout = fopen (statefile,"w");
	if (fout != NULL){
		for (vector<string>::iterator it = tb.begin();
			it != tb.end(); it++){
			fprintf (fout,"%s\n",it->c_str());
		}
		fclose (fout);
	}
}

#include "vipalias.lock.h"

int main (int argc, char *argv[])
{
	int ret = -1;
	vector<string> tb;
	if (argc == 3 && strcmp(argv[1],"get")==0){
		const char *name = argv[2];
		if (vipalias_lock() != -1){
			vallocctx_read(tb);
			int pos = vallocctx_find (tb,name);
			if (pos == -1){
				pos = vallocctx_find(tb,"-");
				if (pos != -1){
					tb[pos] = name;
				}else{
					pos = tb.size();
					tb.push_back(name);
				}
				vallocctx_write (tb);
			}
			
			printf ("%d\n",pos);
			vipalias_unlock();
			ret = 0;
		}
	}else if (argc == 3 && strcmp(argv[1],"unset")==0){
		const char *name = argv[2];
		if (vipalias_lock() != -1){
			vallocctx_read(tb);
			int pos = vallocctx_find (tb,name);
			if (pos != -1){
				tb[pos] = "-";
				vallocctx_write (tb);
				ret = 0;
			}
			vipalias_unlock();
		}
	}else if (argc == 2 && strcmp(argv[1],"list")==0){
		if (vipalias_lock() != -1){
			vallocctx_read(tb);
			int n = 0;
			for (vector<string>::iterator it=tb.begin();
				it != tb.end(); it++,n++){
				if (*it != "-"){
					printf ("%d %s\n",n,it->c_str());
				}
			}
			vipalias_unlock();
			ret = 0;
		}
	}else{
		usage();
	}
	return ret;
}