tools/lib/api/io_dir.h

Source file repositories/reference/linux-study-clean/tools/lib/api/io_dir.h

File Facts

System
Linux kernel
Corpus path
tools/lib/api/io_dir.h
Extension
.h
Size
2554 bytes
Lines
106
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 io_dirent64 {
	ino64_t        d_ino;    /* 64-bit inode number */
	off64_t        d_off;    /* 64-bit offset to next structure */
	unsigned short d_reclen; /* Size of this dirent */
	unsigned char  d_type;   /* File type */
	char           d_name[NAME_MAX + 1]; /* Filename (null-terminated) */
};

struct io_dir {
	int dirfd;
	ssize_t available_bytes;
	struct io_dirent64 *next;
	struct io_dirent64 buff[4];
};

static inline void io_dir__init(struct io_dir *iod, int dirfd)
{
	iod->dirfd = dirfd;
	iod->available_bytes = 0;
}

static inline void io_dir__rewinddir(struct io_dir *iod)
{
	lseek(iod->dirfd, 0, SEEK_SET);
	iod->available_bytes = 0;
}

static inline struct io_dirent64 *io_dir__readdir(struct io_dir *iod)
{
	struct io_dirent64 *entry;

	if (iod->available_bytes <= 0) {
		ssize_t rc = perf_getdents64(iod->dirfd, iod->buff, sizeof(iod->buff));

		if (rc <= 0)
			return NULL;
		iod->available_bytes = rc;
		iod->next = iod->buff;
	}
	entry = iod->next;
	iod->next = (struct io_dirent64 *)((char *)entry + entry->d_reclen);
	iod->available_bytes -= entry->d_reclen;
	return entry;
}

static inline bool io_dir__is_dir(const struct io_dir *iod, struct io_dirent64 *dent)
{
	if (dent->d_type == DT_UNKNOWN) {
		struct stat st;

		if (fstatat(iod->dirfd, dent->d_name, &st, /*flags=*/0))
			return false;

		if (S_ISDIR(st.st_mode)) {
			dent->d_type = DT_DIR;
			return true;
		}
	}
	return dent->d_type == DT_DIR;
}

#endif  /* __API_IO_DIR__ */

Annotation

Implementation Notes