source: MondoRescue/branches/3.3/mindi-busybox/libbb/simplify_path.c@ 3626

/* vi: set sw=4 ts=4: */
/*
 * bb_simplify_path implementation for busybox
 *
 * Copyright (C) 2001  Manuel Novoa III  <mjn3@codepoet.org>
 *
 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
 */
#include "libbb.h"

char* FAST_FUNC bb_simplify_abs_path_inplace(char *start)
{
    char *s, *p;

    p = s = start;
    do {
        if (*p == '/') {
            if (*s == '/') {  /* skip duplicate (or initial) slash */
                continue;
            }
            if (*s == '.') {
                if (s[1] == '/' || !s[1]) {  /* remove extra '.' */
                    continue;
                }
                if ((s[1] == '.') && (s[2] == '/' || !s[2])) {
                    ++s;
                    if (p > start) {
                        while (*--p != '/')  /* omit previous dir */
                            continue;
                    }
                    continue;
                }
            }
        }
        *++p = *s;
    } while (*++s);

    if ((p == start) || (*p != '/')) {  /* not a trailing slash */
        ++p;  /* so keep last character */
    }
    *p = '\0';
    return p;
}

char* FAST_FUNC bb_simplify_path(const char *path)
{
    char *s, *p;

    if (path[0] == '/')
        s = xstrdup(path);
    else {
        p = xrealloc_getcwd_or_warn(NULL);
        s = concat_path_file(p, path);
        free(p);
    }

    bb_simplify_abs_path_inplace(s);
    return s;
}