tools/include/nolibc/dirent.h

Source file repositories/reference/linux-study-clean/tools/include/nolibc/dirent.h

File Facts

System
Linux kernel
Corpus path
tools/include/nolibc/dirent.h
Extension
.h
Size
1890 bytes
Lines
101
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

struct dirent {
	ino_t	d_ino;
	char	d_name[NAME_MAX + 1];
};

/* See comment of FILE in stdio.h */
typedef struct {
	char dummy[1];
} DIR;

static __attribute__((unused))
DIR *fdopendir(int fd)
{
	if (fd < 0) {
		SET_ERRNO(EBADF);
		return NULL;
	}
	return (DIR *)(intptr_t)~fd;
}

static __attribute__((unused))
DIR *opendir(const char *name)
{
	int fd;

	fd = open(name, O_RDONLY);
	if (fd == -1)
		return NULL;
	return fdopendir(fd);
}

static __attribute__((unused))
int closedir(DIR *dirp)
{
	intptr_t i = (intptr_t)dirp;

	if (i >= 0) {
		SET_ERRNO(EBADF);
		return -1;
	}
	return close(~i);
}

static __attribute__((unused))
int readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result)
{
	char buf[sizeof(struct linux_dirent64) + NAME_MAX + 1] __nolibc_aligned_as(struct linux_dirent64);
	struct linux_dirent64 *ldir = (void *)buf;
	intptr_t i = (intptr_t)dirp;
	int fd, ret;

	if (i >= 0)
		return EBADF;

	fd = ~i;

	ret = _sys_getdents64(fd, ldir, sizeof(buf));
	if (ret < 0)
		return -ret;
	if (ret == 0) {
		*result = NULL;
		return 0;
	}

	/*
	 * getdents64() returns as many entries as fit the buffer.
	 * readdir() can only return one entry at a time.
	 * Make sure the non-returned ones are not skipped.
	 */
	ret = _sys_lseek(fd, ldir->d_off, SEEK_SET);
	if (ret < 0)
		return -ret;

	entry->d_ino = ldir->d_ino;
	/* the destination should always be big enough */
	strlcpy(entry->d_name, ldir->d_name, sizeof(entry->d_name));
	*result = entry;
	return 0;
}

#endif /* _NOLIBC_DIRENT_H */

Annotation

Implementation Notes