BSD 4_3 development

[unix-history] / usr / contrib / mh / sbr / path.c

/* path.c - return a pathname */

#include "../h/mh.h"
#include <stdio.h>

#define CWD     "./"
#define NCWD    (sizeof CWD - 1)
#define DOT     "."
#define DOTDOT  ".."
#define PWD     "../"
#define NPWD    (sizeof PWD - 1)


static char *pwds;

char   *expath ();


char   *path (name, flag)
register char   *name;
register int     flag;
{
   register char  *cp,
                  *ep;

   if ((cp = expath (name, flag))
           && (ep = cp + strlen (cp) - 1) > cp
           && *ep == '/')
       *ep = NULL;

   return cp;
}

/* \f */

static  char   *expath (name, flag)
register char   *name;
register int     flag;
{
   register char  *cp,
                  *ep;
   char    buffer[BUFSIZ];

   if (flag == TSUBCWF) {
       (void) sprintf (buffer, "%s/%s", m_getfolder (), name);
       name = m_mailpath (buffer);
       compath (name);
       (void) sprintf (buffer, "%s/", m_maildir (""));
       if (ssequal (buffer, name)) {
           cp = name;
           name = getcpy (name + strlen (buffer));
           free (cp);
       }
       flag = TFOLDER;
   }

   if (*name == '/'
           || (flag == TFOLDER
               && (strncmp (name, CWD, NCWD)
                   && strcmp (name, DOT)
                   && strcmp (name, DOTDOT)
                   && strncmp (name, PWD, NPWD))))
       return getcpy (name);

   if (pwds == NULL)
       pwds = pwd ();

   if (strcmp (name, DOT) == 0 || strcmp (name, CWD) == 0)
       return getcpy (pwds);

   ep = pwds + strlen (pwds);
   if ((cp = rindex (pwds, '/')) == NULL)
       cp = ep;
   else
       if (cp == pwds)
           cp++;

   if (strncmp (name, CWD, NCWD) == 0)
       name += NCWD;

   if (strcmp (name, DOTDOT) == 0 || strcmp (name, PWD) == 0) {
       (void) sprintf (buffer, "%.*s", cp - pwds, pwds);
       return getcpy (buffer);
   }

   if (strncmp (name, PWD, NPWD) == 0)
       name += NPWD;
   else
       cp = ep;

   (void) sprintf (buffer, "%.*s/%s", cp - pwds, pwds, name);
   return getcpy (buffer);
}

/* \f */

static  compath (f)
register char  *f;
{
   register char  *cp,
                  *dp;

   if (*f != '/')
       return;

   for (cp = f; *cp;)
       if (*cp == '/') {
           switch (*++cp) {
               case NULL: 
                   if (--cp > f)
                       *cp = NULL;
                   break;

               case '/': 
                   for (dp = cp; *dp == '/'; dp++)
                       continue;
                   (void) strcpy (cp--, dp);
                   continue;

               case '.': 
                   if (strcmp (cp, DOT) == 0) {
                       if (cp > f + 1)
                           cp--;
                       *cp = NULL;
                       break;
                   }
                   if (strcmp (cp, DOTDOT) == 0) {
                       for (cp -= 2; cp > f; cp--)
                           if (*cp == '/')
                               break;
                       if (cp <= f)
                           cp = f + 1;
                       *cp = NULL;
                       break;
                   }
                   if (strncmp (cp, PWD, NPWD) == 0) {
                       for (dp = cp - 2; dp > f; dp--)
                           if (*dp == '/')
                               break;
                       if (dp <= f)
                           dp = f;
                       (void) strcpy (dp, cp + NPWD - 1);
                       cp = dp;
                       continue;
                   }
                   if (strncmp (cp, CWD, NCWD) == 0) {
                       (void) strcpy (cp - 1, cp + NCWD - 1);
                       cp--;
                       continue;
                   }
                   continue;

               default: 
                   cp++;
                   continue;
           }
           break;
       }
       else
           cp++;
}