// read_line.cc
// Kevin Karplus
// 20 Oct 1995 separated from Input.cc

#include "Input.h"
#include <string.h>

// Read a line (skipping comments and blank lines)
//	and strip leading white space.
// Allocate new storage for it, and return the char* string.
// Return 0 if no more data.
char *read_line(istream &in)
{
    int buf_len=8188;
    char *buf=new char[buf_len];
    buf[0]=0;
    get_word(in, buf);
    if (buf[0]==0) 
    {   delete [] buf;
        return 0;
    }
    int end=strlen(buf);
    char c;
    while(in.get(c) && c!='\n')
    {   if (end >=buf_len-1)
        {   // reallocate the buffer
	    int new_len = buf_len*2;
	    char *new_buf=new char[new_len];
	    for(int i=buf_len-1; i>=0; i--)
		new_buf[i] = buf[i];
	    delete [] buf;
	    buf=new_buf;
	    buf_len = new_len;
	}
	buf[end++] = c;
    }
    buf[end] = 0;
    char *ret = new char[end+1];
    strcpy(ret, buf);
    delete [] buf;
    return ret;
}