fixed case of "/". DLW

[unix-history] / usr / src / usr.bin / f77 / libU77 / getcwd_.c

/** F77 NOTE: the getcwd() routine should be in libc.a ! **/
/*
* return name of working (current) directory
*/
#include        <stdio.h>
#include        <sys/param.h>
#include        <sys/stat.h>
#include        <sys/dir.h>

static char     slash[] = "/";
static char     dot[]   = ".";
static char     dotdot[] = "..";
static char     name[128];

char *
getcwd()
{
       int     rdev, rino;
       int     fd;
       struct  stat    d, dd;
       struct  direct  dir;
       char    *prepend();
       char    *namep = &name[(sizeof name)-1];

       *namep = '\0';
       stat(slash, &d);
       rdev = d.st_dev;
       rino = d.st_ino;
       for (;;)
       {
               stat(dot, &d);
               if (d.st_ino == rino && d.st_dev == rdev)
               {
                       if (*namep == '\0')     /* rootdir is a special case */
                               namep = prepend(namep, slash);
                       chdir(namep);
                       return(namep);
               }
               if ((fd = open(dotdot,0)) < 0)
               {
                       chdir(prepend(namep, dot));
                       return((char *)0);
               }
               chdir(dotdot);
               fstat(fd, &dd);
               if(d.st_dev == dd.st_dev)
               {
                       if(d.st_ino == dd.st_ino)
                       {
                               close(fd);
                               if (*namep == '\0') /* root is a special case */
                                       namep = prepend(namep, slash);
                               chdir(namep);
                               return(namep);
                       }
                       do
                       {
                               if (read(fd, (char *)&dir, sizeof(dir)) < sizeof(dir))
                               {
                                       close(fd);
                                       chdir(prepend(namep, dot));
                                       return((char *)0);
                               }
                       } while (dir.d_ino != d.st_ino);
               }
               else do
               {
                               if(read(fd, (char *)&dir, sizeof(dir)) < sizeof(dir))
                               {
                                       close(fd);
                                       chdir(prepend(namep, dot));
                                       return((char *)0);
                               }
                               stat(dir.d_name, &dd);
                       } while(dd.st_ino != d.st_ino || dd.st_dev != d.st_dev);
               close(fd);
               namep = prepend(prepend(namep, dir.d_name), slash);
       }
}

char *
prepend(p, n)
char *p;
char *n;
{
       int i = 0;

       while (i < DIRSIZ && *n)
       {
               n++; i++;
       }
       while (i--)
               *--p = *--n;
       return(p);
}

/*
char id_getcwd[] = "@(#)getcwd_.c       1.3";
* Get pathname of current working directory.
*
* calling sequence:
*      character*128 path
*      ierr = getcwd(path)
* where:
*      path will receive the pathname of the current working directory.
*      ierr will be 0 if successful, a system error code otherwise.
*/

extern int errno;

long
getcwd_(path, len)
char *path;
long len;
{
       char *p;

       p = getcwd();
       if (p)
       {
               b_char(p, path, len);
               return(0L);
       }
       return((long)errno);
}