bsd-glob.c

功能强大的ftp服务器源代码

    qpatnext = pattern;
#endif
    oldpathc = pglob->gl_pathc;
    bufnext = patbuf;

    /* We don't need to check for buffer overflow any more. */
    while ((c = *qpatnext++) != EOS) {
        switch (c) {
        case LBRACKET:
            c = *qpatnext;
            if (c == NOT)
                ++qpatnext;
            if (*qpatnext == EOS ||
                g_strchr((const Char *) qpatnext + 1, RBRACKET) == NULL) {
                *bufnext++ = LBRACKET;
                if (c == NOT)
                    --qpatnext;
                break;
            }
            *bufnext++ = M_SET;
            if (c == NOT)
                *bufnext++ = M_NOT;
            c = *qpatnext++;
            do {
                *bufnext++ = CHAR(c);
                if (*qpatnext == RANGE && (c = qpatnext[1]) != RBRACKET) {
                    *bufnext++ = M_RNG;
                    *bufnext++ = CHAR(c);
                    qpatnext += 2;
                }
            } while ((c = *qpatnext++) != RBRACKET);
            pglob->gl_flags |= GLOB_MAGCHAR;
            *bufnext++ = M_END;
            break;
        case QUESTION:
            pglob->gl_flags |= GLOB_MAGCHAR;
            *bufnext++ = M_ONE;
            break;
        case STAR:
            pglob->gl_flags |= GLOB_MAGCHAR;
            /* collapse adjacent stars to one,
             * to avoid exponential behavior
             */
            if (bufnext == patbuf || bufnext[-1] != M_ALL) {
                *bufnext++ = M_ALL;
            }
            break;
        default:
            *bufnext++ = CHAR(c);
            break;
        }
    }
    *bufnext = EOS;

    if ((err = glob1(patbuf, patbuf + MAXPATHLEN, pglob, &limit)) != 0) {
        return (err);
    }

    /*
     * If there was no match we are going to append the pattern
     * if GLOB_NOCHECK was specified or if GLOB_NOMAGIC was specified
     * and the pattern did not contain any magic characters
     * GLOB_NOMAGIC is there just for compatibility with csh.
     */
    if (pglob->gl_pathc == oldpathc) {
        return (GLOB_NOMATCH);
    }
    if (!(pglob->gl_flags & GLOB_NOSORT)) {
        qsort(pglob->gl_pathv + oldpathc,
              (size_t) (pglob->gl_pathc - oldpathc), sizeof (char *), compare);
    }
    return 0;
}

static int compare(const void *p, const void *q)
{
    return (strcmp(*(const char **) p, *(const char **) q));
}

static int
glob1(Char * pattern, Char * pattern_last, glob_t * pglob, size_t * limitp)
{
    Char pathbuf[MAXPATHLEN + 1];

    /* A null pathname is invalid -- POSIX 1003.1 sect. 2.4. */
    if (*pattern == EOS) {
        return 0;
    }
    return (glob2(pathbuf, pathbuf + MAXPATHLEN,
                  pathbuf, pathbuf + MAXPATHLEN,
                  pattern, pattern_last, pglob, limitp, 0));
}

/*
 * The functions glob2 and glob3 are mutually recursive; there is one level
 * of recursion for each segment in the pattern that contains one or more
 * meta characters.
 */
static int
glob2(Char * pathbuf,
      Char * pathbuf_last,
      Char * pathend,
      Char * pathend_last,
      Char * pattern,
      Char * pattern_last, glob_t * pglob, size_t * limitp, int recursion)
{
    struct stat sb;
    Char *p, *q;
    int anymeta;

    if (pglob->gl_maxdepth > 0 && recursion > pglob->gl_maxdepth) {
        errno = 0;
        return (GLOB_NOSPACE);
    }
    /*
     * Loop over pattern segments until end of pattern or until
     * segment with meta character found.
     */
    for (anymeta = 0;;) {
        if (*pattern == EOS) {  /* End of pattern? */
            *pathend = EOS;
            if (g_lstat(pathbuf, &sb))
                return 0;

            ++pglob->gl_matchc;
            return (globextend(pathbuf, pglob, limitp));
        }

        /* Find end of next segment, copy tentatively to pathend. */
        q = pathend;
        p = pattern;
        while (*p != EOS && *p != SEP) {
            if (ismeta(*p))
                anymeta = 1;
            if (q + 1 > pathend_last)
                return 1;
            *q++ = *p++;
        }

        if (!anymeta) {         /* No expansion, do next segment. */
            pathend = q;
            pattern = p;
            while (*pattern == SEP) {
                if (pathend + 1 > pathend_last)
                    return 1;
                *pathend++ = *pattern++;
            }
        } else
            /* Need expansion, recurse. */
            return (glob3(pathbuf, pathbuf_last, pathend,
                          pathend_last, pattern,
                          p, pattern_last, pglob, limitp, recursion + 1));
    }
    /* NOTREACHED */
}

static int
glob3(Char * pathbuf, Char * pathbuf_last, Char * pathend,
      Char * pathend_last, Char * pattern, Char * restpattern,
      Char * restpattern_last, glob_t * pglob, size_t * limitp,
      int recursion)
{
    register struct dirent *dp;
    DIR *dirp;
    int err;
    char buf[MAXPATHLEN + 1];

    if (pathend > pathend_last)
        return 1;

    *pathend = EOS;
    errno = 0;

    if (pglob->gl_maxdepth > 0 && recursion > pglob->gl_maxdepth) {
        return (GLOB_NOSPACE);
    }

    if ((dirp = g_opendir(pathbuf)) == NULL) {
        /* TODO: don't call for ENOENT or ENOTDIR? */
        if (pglob->gl_errfunc) {
            if (g_Ctoc(pathbuf, buf, sizeof (buf))) {
                return (GLOB_ABORTED);
            }
            if (pglob->gl_errfunc(buf, errno) ||
                pglob->gl_flags & GLOB_ERR) {
                return (GLOB_ABORTED);
            }
        }
        return 0;
    }

    err = 0;

    while ((dp = (*readdir) (dirp))) {
        register unsigned char *sc;
        register Char *dc;

        /* Initial DOT must be matched literally. */
        if (dp->d_name[0] == DOT && *pattern != DOT) {
            continue;
        }
#ifndef GLOB_UNPRINTABLE
        if (checkprintable(dp->d_name) != 0) {
            continue;
        }
#endif
        dc = pathend;
        sc = (unsigned char *) dp->d_name;
        while (dc < pathend_last && (*dc++ = *sc++) != EOS);
        if (dc >= pathend_last) {
            *dc = EOS;
            err = 1;
            break;
        }

        if (!match(pathend, pattern, restpattern)) {
            *pathend = EOS;
            continue;
        }
        err = glob2(pathbuf, pathbuf_last, --dc, pathend_last,
                    restpattern, restpattern_last, pglob, limitp,
                    recursion + 1);
        if (err)
            break;
    }

    closedir(dirp);
    return (err);
}


/*
 * Extend the gl_pathv member of a glob_t structure to accommodate a new item,
 * add the new item, and update gl_pathc.
 *
 * This assumes the BSD realloc, which only copies the block when its size
 * crosses a power-of-two boundary; for v7 realloc, this would cause quadratic
 * behavior.
 *
 * Return 0 if new item added, error code if memory couldn't be allocated.
 *
 * Invariant of the glob_t structure:
 *    Either gl_pathc is zero and gl_pathv is NULL; or gl_pathc > 0 and
 *    gl_pathv points to (gl_offs + gl_pathc + 1) items.
 */
static int globextend(const Char * path, glob_t * pglob, size_t * limitp)
{
    register char **pathv;
    unsigned int newsize;
    size_t len;
    char *copy;
    const Char *p;

    if (pglob->gl_maxfiles != (unsigned long) -1) {
        if (pglob->gl_maxfiles == 0) {
            return 0;
        }
        pglob->gl_maxfiles--;
    }
    newsize = sizeof (*pathv) * (2 + pglob->gl_pathc);
    pathv = pglob->gl_pathv ? realloc((char *) pglob->gl_pathv, newsize) :
        malloc(newsize);
    if (pathv == NULL) {
        free(pglob->gl_pathv);
        pglob->gl_pathv = NULL;
        return (GLOB_NOSPACE);
    }

    pglob->gl_pathv = pathv;

    for (p = path; *p++;);
    len = (size_t) (p - path);
    *limitp += len;
    if ((copy = malloc(len)) != NULL) {
        if (g_Ctoc(path, copy, len)) {
            free(copy);
            return (GLOB_NOSPACE);
        }
        pathv[pglob->gl_pathc++] = copy;
    }
    pathv[pglob->gl_pathc] = NULL;

#ifdef USELESS_FOR_PUREFTPD
    if ((pglob->gl_flags & GLOB_LIMIT) && newsize + *limitp >= ARG_MAX) {
        errno = 0;
        return (GLOB_NOSPACE);
    }
#endif

    return (copy == NULL ? GLOB_NOSPACE : 0);
}


/*
 * pattern matching function for filenames.  Each occurrence of the *
 * pattern causes a recursion level.
 */
static int
match(register Char * name, register Char * pat, register Char * patend)
{
    int ok, negate_range;
    Char c, k;

    while (pat < patend) {
        c = *pat++;
        switch (c & M_MASK) {
        case M_ALL:
            if (pat == patend)
                return 1;
            do {
                if (match(name, pat, patend)) {
                    return 1;
                }
            } while (*name++ != EOS);
            return 0;
        case M_ONE:
            if (*name++ == EOS) {
                return 0;
            }
            break;
        case M_SET:
            ok = 0;
            if ((k = *name++) == EOS)
                return 0;
            if ((negate_range = ((*pat & M_MASK) == M_NOT)) != EOS) {
                ++pat;
            }
            while (((c = *pat++) & M_MASK) != M_END) {
                if ((*pat & M_MASK) == M_RNG) {
                    if (c <= k && k <= pat[1])
                        ok = 1;
                    pat += 2;
                } else if (c == k) {
                    ok = 1;
                }
            }
            if (ok == negate_range) {
                return 0;
            }
            break;
        default:
            if (*name++ != c) {
                return 0;
            }
            break;
        }
    }
    return (*name == EOS);
}

/* Free allocated data belonging to a glob_t structure. */
void globfree(glob_t * pglob)
{
    register int i;
    register char **pp;

    if (pglob->gl_pathv != NULL) {
        pp = pglob->gl_pathv;
        for (i = pglob->gl_pathc; i--; ++pp) {
            free(*pp);
        }
        free(pglob->gl_pathv);
        pglob->gl_pathv = NULL;
    }
}

static DIR *g_opendir(register Char * str)
{
    char buf[MAXPATHLEN + 1];

    if (!*str) {
	buf[0] = '.';
	buf[1] = 0;         /* safe : sizeof buf > 2 */
    } else {
        if (g_Ctoc(str, buf, sizeof (buf)))
            return NULL;
    }
    return (opendir(buf));
}

static int g_lstat(register Char * fn, struct stat *sb)
{
    char buf[MAXPATHLEN + 1];

    if (g_Ctoc(fn, buf, sizeof (buf)))
        return -1;
    return (lstat(buf, sb));
}

static const Char *g_strchr(const Char * str, int ch)
{
    do {
        if (*str == (Char) ch)
            return (str);
    } while (*str++);
    return NULL;
}

static int g_Ctoc(register const Char * str, char *buf, unsigned int len)
{
    while (len--) {
        if ((*buf++ = (char) *str++) == EOS)
            return 0;
    }
    return 1;
}
#else
extern signed char v6ready;
#endif