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bool initrd_next(dirent_t *dirent)
{
	initrd_head_t header;
	media_acquire(dirent->d_resv[INITRD_MEDIA]);
	media_begin(dirent->d_resv[INITRD_MEDIA]);
	media_read(dirent->d_resv[INITRD_MEDIA], 0, 1, &header);

	initrd_record_t *records;
	records = (initrd_record_t*) kmalloc(512*header.nblkat);
	if (!records)
	{
		media_release(dirent->d_resv[INITRD_MEDIA]);
		return false;
	};
	media_read(dirent->d_resv[INITRD_MEDIA], 1, header.nblkat, records);
	media_end(dirent->d_resv[INITRD_MEDIA]);
	media_release(dirent->d_resv[INITRD_MEDIA]);

	/* check to see if there IS a next record */
	printk("initrd_next: "); printk(dirent->d_name); printk(" next="); printk(records[dirent->d_fileno+1].filename);
	printk("fileno_current="); printdec(dirent->d_fileno); printk("\n");
	if (records[dirent->d_fileno+1].filename[0] != 0)
	{
		int fno = dirent->d_fileno+1;
		dirent->d_fileno = fno;
		strcpy(dirent->d_name, records[fno].filename);
		printk("initrd_next: "); printk(dirent->d_name); printk(" fileno="); printdec(dirent->d_fileno); printk("\n");
		dirent->d_type = records[fno].type;
		kfree(records);
		return true;
	};

	return false;
};

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bool search_file(dirent_t *dirent, filesystem_t *fs, char * filename)
{
	if (filename[0] == '/') return true;
	printk("search_file: "); printk(filename); printk("\n");
	while (strcmp(dirent->d_name, filename) != 0)
	{
		printk("dirent->d_name: "); printk(dirent->d_name); printk("\n");
		if (!fs->nodi_next(dirent))
		{
			fs->nodi_add(dirent, filename, DT_REG);
		};
	};
	return true;
};

bool *find_node(dirent_t *dirent, pathname_t *pathname)
{
	if (!pathname) return false;
	while (pathname != NULL)
	{
		if (!search_file(dirent, rootfs, pathname->name)) return false;
		if (pathname->next != NULL)
		{
			if (!rootfs->nodi_down(dirent)) return false;
		};
		pathname = pathname->next;
	};
	return true;
};

iohandle_t *open(const char * filename)
{
	pathname_t *pathname = (pathname_t*) kmalloc(sizeof(pathname_t));
	int t;
	t = pathname_split(filename, pathname);
	if (t == FP_BAD) return NULL;
	if (t == FP_RELATIVE)
	{
		u32int temp = (u32int) pathname;
		pathname = pathname_absolute(pathname);
		kfree(temp);
	};
	dirent_t *dirent;
	dirent = (dirent_t*) kmalloc(sizeof(dirent_t));
	memcpy(dirent, rootdirent, sizeof(dirent_t));
	if(!find_node(dirent, pathname)) return NULL;
	return rootfs->nodi_getio(dirent);
};

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/* the following driver functions should update the flags field upon result */
typedef void (*media_read_t)(struct media_struct*, u32int, u32int, char*);
typedef void (*media_write_t)(struct media_struct*, u32int, u32int, char*);
typedef void (*media_begin_t)(struct media_struct*);
typedef void (*media_end_t)(struct media_struct*);

typedef struct media_struct
{
	char		label[128];		/* 'label' (or 'name') of the media. */
	u32int		size;			/* size (in blocks!) of the media. */
	u32int		flags;			/* any extra flags */
	bool		lock;			/* is the lock active? */
	u32int		id;			/* recognised by DRIVER, not the whole kernel */
	media_read_t	mread;
	media_write_t	mwrite;
	media_begin_t	mbegin;
	media_end_t	mend;
} __attribute__ ((packed)) media_t;

bool media_poll(media_t *media)
{
	return !media->lock;
};

void media_acquire(media_t *media)
{
	while (!media_poll(media));
	media->lock = true;
};

void media_release(media_t *media)
{
	media->lock = false;
};

void media_begin(media_t *media)
{
	media->mbegin(media);
};

void media_end(media_t *media)
{
	media->mend(media);
};

void media_read(media_t *media, u32int sector, u32int count, char * buffer)
{
	media->mread(media, sector, count, buffer);
};

void media_write(media_t *media, u32int sector, u32int count, char * buffer)
{
	media->mwrite(media, sector, count, buffer);
};

#endif

Code: Select all

	debug("Initialising initrd filesystem...\n");
	rootfs = &fs_initrd;
	initrd_media = create_ramdisk(begin, end, "initrd");
	if(!initrd_media) halt("failed to create ramdisk");
	rootdirent = rootfs->init(initrd_media, 1, -1);
	if (!rootdirent) halt("initrdfs reports error!");

	printk("hi.\n");
	iohandle_t *fp = open("/hello.txt");
	printk("hi again.\n");
	if (!fp) halt("failed.");
	char buffer[1024];
	read(buffer, 1, 5, fp);
	close(fp);

Code: Select all

dirent->d_name: /
initrd_next: / next=fileno_current=0