glob.c

Newlib 嵌入式 C库 标准实现代码

			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;
#ifdef DEBUG
	qprintf("glob0:", patbuf);
#endif

	if ((err = glob1(patbuf, 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 &&
	    ((pglob->gl_flags & GLOB_NOCHECK) ||
	      ((pglob->gl_flags & GLOB_NOMAGIC) &&
	       !(pglob->gl_flags & GLOB_MAGCHAR))))
		return(globextend(pattern, pglob, limit));
	else if (!(pglob->gl_flags & GLOB_NOSORT))
		qsort(pglob->gl_pathv + pglob->gl_offs + oldpathc,
		    pglob->gl_pathc - oldpathc, sizeof(char *), compare);
	return(0);
}

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

static int
glob1(pattern, pglob, limit)
	Char *pattern;
	glob_t *pglob;
	int *limit;
{
	Char pathbuf[MAXPATHLEN];

	/* A null pathname is invalid -- POSIX 1003.1 sect. 2.4. */
	if (*pattern == EOS)
		return(0);
	return(glob2(pathbuf, pathbuf, pathbuf + MAXPATHLEN - 1,
	    pattern, pglob, limit));
}

/*
 * 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(pathbuf, pathend, pathend_last, pattern, pglob, limit)
	Char *pathbuf, *pathend, *pathend_last, *pattern;
	glob_t *pglob;
	int *limit;
{
	struct stat sb;
	Char *p, *q;
	int anymeta;

	/*
	 * 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, pglob))
				return(0);

			if (((pglob->gl_flags & GLOB_MARK) &&
			    pathend[-1] != SEP) && (S_ISDIR(sb.st_mode)
			    || (S_ISLNK(sb.st_mode) &&
			    (g_stat(pathbuf, &sb, pglob) == 0) &&
			    S_ISDIR(sb.st_mode)))) {
				if (pathend + 1 > pathend_last)
					return (1);
				*pathend++ = SEP;
				*pathend = EOS;
			}
			++pglob->gl_matchc;
			return(globextend(pathbuf, pglob, limit));
		}

		/* 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, pathend, pathend_last, pattern, p,
			    pglob, limit));
	}
	/* NOTREACHED */
}

static int
glob3(pathbuf, pathend, pathend_last, pattern, restpattern, pglob, limit)
	Char *pathbuf, *pathend, *pathend_last, *pattern, *restpattern;
	glob_t *pglob;
	int *limit;
{
	struct dirent *dp;
	DIR *dirp;
	int err;
	char buf[MAXPATHLEN];

	/*
	 * The readdirfunc declaration can't be prototyped, because it is
	 * assigned, below, to two functions which are prototyped in glob.h
	 * and dirent.h as taking pointers to differently typed opaque
	 * structures.
	 */
	struct dirent *(*readdirfunc)();

	if (pathend > pathend_last)
		return (1);
	*pathend = EOS;
	errno = 0;

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

	err = 0;

	/* Search directory for matching names. */
	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
		readdirfunc = pglob->gl_readdir;
	else
		readdirfunc = readdir;
	while ((dp = (*readdirfunc)(dirp))) {
		u_char *sc;
		Char *dc;

		/* Initial DOT must be matched literally. */
		if (dp->d_name[0] == DOT && *pattern != DOT)
			continue;
		dc = pathend;
		sc = (u_char *) dp->d_name;
		while (dc < pathend_last && (*dc++ = *sc++) != EOS)
			;
		if (!match(pathend, pattern, restpattern)) {
			*pathend = EOS;
			continue;
		}
		err = glob2(pathbuf, --dc, pathend_last, restpattern,
		    pglob, limit);
		if (err)
			break;
	}

	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
		(*pglob->gl_closedir)(dirp);
	else
		closedir(dirp);
	return(err);
}


/*
 * Extend the gl_pathv member of a glob_t structure to accomodate 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(path, pglob, limit)
	const Char *path;
	glob_t *pglob;
	int *limit;
{
	char **pathv;
	int i;
	u_int newsize, len;
	char *copy;
	const Char *p;

	if (*limit && pglob->gl_pathc > *limit) {
		errno = 0;
		return (GLOB_NOSPACE);
	}

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

	if (pglob->gl_pathv == NULL && pglob->gl_offs > 0) {
		/* first time around -- clear initial gl_offs items */
		pathv += pglob->gl_offs;
		for (i = pglob->gl_offs; --i >= 0; )
			*--pathv = NULL;
	}
	pglob->gl_pathv = pathv;

	for (p = path; *p++;)
		continue;
	len = (size_t)(p - path);
	if ((copy = malloc(len)) != NULL) {
		if (g_Ctoc(path, copy, len)) {
			free(copy);
			return (GLOB_NOSPACE);
		}
		pathv[pglob->gl_offs + pglob->gl_pathc++] = copy;
	}
	pathv[pglob->gl_offs + pglob->gl_pathc] = NULL;
	return(copy == NULL ? GLOB_NOSPACE : 0);
}

/*
 * pattern matching function for filenames.  Each occurrence of the *
 * pattern causes a recursion level.
 */
static int
match(name, pat, patend)
	Char *name, *pat, *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 (__collate_load_error ?
					    CHAR(c) <= CHAR(k) && CHAR(k) <= CHAR(pat[1]) :
					       __collate_range_cmp(CHAR(c), CHAR(k)) <= 0
					    && __collate_range_cmp(CHAR(k), CHAR(pat[1])) <= 0
					   )
						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(pglob)
	glob_t *pglob;
{
	int i;
	char **pp;

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

static DIR *
g_opendir(str, pglob)
	Char *str;
	glob_t *pglob;
{
	char buf[MAXPATHLEN];

	if (!*str)
		strcpy(buf, ".");
	else {
		if (g_Ctoc(str, buf, sizeof(buf)))
			return (NULL);
	}

	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
		return((*pglob->gl_opendir)(buf));

	return(opendir(buf));
}

static int
g_lstat(fn, sb, pglob)
	Char *fn;
	struct stat *sb;
	glob_t *pglob;
{
	char buf[MAXPATHLEN];

	if (g_Ctoc(fn, buf, sizeof(buf))) {
		errno = ENAMETOOLONG;
		return (-1);
	}
	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
		return((*pglob->gl_lstat)(buf, sb));
	return(lstat(buf, sb));
}

static int
g_stat(fn, sb, pglob)
	Char *fn;
	struct stat *sb;
	glob_t *pglob;
{
	char buf[MAXPATHLEN];

	if (g_Ctoc(fn, buf, sizeof(buf))) {
		errno = ENAMETOOLONG;
		return (-1);
	}
	if (pglob->gl_flags & GLOB_ALTDIRFUNC)
		return((*pglob->gl_stat)(buf, sb));
	return(stat(buf, sb));
}

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

static int
g_Ctoc(str, buf, len)
	const Char *str;
	char *buf;
	u_int len;
{

	while (len--) {
		if ((*buf++ = *str++) == '\0')
			return (0);
	}
	return (1);
}

#ifdef DEBUG
static void
qprintf(str, s)
	const char *str;
	Char *s;
{
	Char *p;

	(void)printf("%s:\n", str);
	for (p = s; *p; p++)
		(void)printf("%c", CHAR(*p));
	(void)printf("\n");
	for (p = s; *p; p++)
		(void)printf("%c", *p & M_PROTECT ? '"' : ' ');
	(void)printf("\n");
	for (p = s; *p; p++)
		(void)printf("%c", ismeta(*p) ? '_' : ' ');
	(void)printf("\n");
}
#endif