integck.c

mtd-utils 是一套更改linux mtd設備的工具

{
	struct dir_entry_info *entry;

	entry = pick_entry(file);
	if (!entry)
		return;
	file_unlink(entry);
}

static void file_delete(struct file_info *file)
{
	struct dir_entry_info *entry = file->links;

	file_close_all(file);
	while (entry) {
		struct dir_entry_info *next = entry->next_link;

		file_unlink(entry);
		entry = next;
	}
}

static void file_info_display(struct file_info *file)
{
	struct dir_entry_info *entry;
	struct write_info *w;
	unsigned wcnt;

	fprintf(stderr, "File Info:\n");
	fprintf(stderr, "    Original name: %s\n", file->name);
	fprintf(stderr, "    Link count: %d\n", file->link_count);
	fprintf(stderr, "    Links:\n");
	entry = file->links;
	while (entry) {
		fprintf(stderr, "      Name: %s\n", entry->name);
		fprintf(stderr, "      Directory: %s\n", entry->parent->name);
		entry = entry->next_link;
	}
	fprintf(stderr, "    Length: %u\n", (unsigned) file->length);
	fprintf(stderr, "    File was open: %s\n",
		(file->fds == NULL) ? "false" : "true");
	fprintf(stderr, "    File was deleted: %s\n",
		(file->deleted == 0) ? "false" : "true");
	fprintf(stderr, "    File was out of space: %s\n",
		(file->no_space_error == 0) ? "false" : "true");
	fprintf(stderr, "    File Data:\n");
	wcnt = 0;
	w = file->writes;
	while (w) {
		fprintf(stderr, "        Offset: %u  Size: %u  Seed: %u"
				"  R.Off: %u\n",
				(unsigned) w->offset,
				(unsigned) w->size,
				(unsigned) w->random_seed,
				(unsigned) w->random_offset);
		wcnt += 1;
		w = w->next;
	}
	fprintf(stderr, "    %u writes\n", wcnt);
	fprintf(stderr, "    ============================================\n");
	fprintf(stderr, "    Write Info:\n");
	wcnt = 0;
	w = file->raw_writes;
	while (w) {
		if (w->trunc)
			fprintf(stderr, "        Trunc from %u to %u\n",
					(unsigned) w->offset,
					(unsigned) w->random_offset);
		else
			fprintf(stderr, "        Offset: %u  Size: %u  Seed: %u"
					"  R.Off: %u\n",
					(unsigned) w->offset,
					(unsigned) w->size,
					(unsigned) w->random_seed,
					(unsigned) w->random_offset);
		wcnt += 1;
		w = w->next;
	}
	fprintf(stderr, "    %u writes or truncations\n", wcnt);
	fprintf(stderr, "    ============================================\n");
}

static struct fd_info *file_open(struct file_info *file)
{
	int fd, flags = O_RDWR;
	char *path;

	path = dir_path(file->links->parent, file->links->name);
	if (tests_random_no(100) == 1)
		flags |= O_SYNC;
	fd = open(path, flags);
	CHECK(fd != -1);
	free(path);
	return add_fd(file, fd);
}

#define BUFFER_SIZE 32768

static size_t file_write_data(	struct file_info *file,
				int fd,
				off_t offset,
				size_t size,
				unsigned seed)
{
	size_t remains, actual, block;
	ssize_t written;
	char buf[BUFFER_SIZE];

	srand(seed);
	CHECK(lseek(fd, offset, SEEK_SET) != (off_t) -1);
	remains = size;
	actual = 0;
	written = BUFFER_SIZE;
	while (remains) {
		/* Fill up buffer with random data */
		if (written < BUFFER_SIZE) {
			memmove(buf, buf + written, BUFFER_SIZE - written);
			written = BUFFER_SIZE - written;
		} else
			written = 0;
		for (; written < BUFFER_SIZE; ++written)
			buf[written] = rand();
		/* Write a block of data */
		if (remains > BUFFER_SIZE)
			block = BUFFER_SIZE;
		else
			block = remains;
		written = write(fd, buf, block);
		if (written < 0) {
			CHECK(errno == ENOSPC); /* File system full */
			full = 1;
			file->no_space_error = 1;
			break;
		}
		remains -= written;
		actual += written;
	}
	return actual;
}

static void file_write_info(struct file_info *file,
			off_t offset,
			size_t size,
			unsigned seed)
{
	struct write_info *new_write, *w, **prev, *tmp;
	int inserted;
	size_t sz;
	off_t end, chg;

	/* Create struct write_info */
	sz = sizeof(struct write_info);
	new_write = (struct write_info *) malloc(sz);
	CHECK(new_write != NULL);
	memset(new_write, 0, sz);
	new_write->offset = offset;
	new_write->size = size;
	new_write->random_seed = seed;

	w = (struct write_info *) malloc(sz);
	CHECK(w != NULL);
	memset(w, 0, sz);
	w->next = file->raw_writes;
	w->offset = offset;
	w->size = size;
	w->random_seed = seed;
	file->raw_writes = w;

	/* Insert it into file->writes */
	inserted = 0;
	end = offset + size;
	w = file->writes;
	prev = &file->writes;
	while (w) {
		if (w->offset >= end) {
			/* w comes after new_write, so insert before it */
			new_write->next = w;
			*prev = new_write;
			inserted = 1;
			break;
		}
		/* w does not come after new_write */
		if (w->offset + w->size > offset) {
			/* w overlaps new_write */
			if (w->offset < offset) {
				/* w begins before new_write begins */
				if (w->offset + w->size <= end)
					/* w ends before new_write ends */
					w->size = offset - w->offset;
				else {
					/* w ends after new_write ends */
					/* Split w */
					tmp = (struct write_info *) malloc(sz);
					CHECK(tmp != NULL);
					*tmp = *w;
					chg = end - tmp->offset;
					tmp->offset += chg;
					tmp->random_offset += chg;
					tmp->size -= chg;
					w->size = offset - w->offset;
					/* Insert new struct write_info */
					w->next = new_write;
					new_write->next = tmp;
					inserted = 1;
					break;
				}
			} else {
				/* w begins after new_write begins */
				if (w->offset + w->size <= end) {
					/* w is completely overlapped,
					   so remove it */
					*prev = w->next;
					tmp = w;
					w = w->next;
					free(tmp);
					continue;
				}
				/* w ends after new_write ends */
				chg = end - w->offset;
				w->offset += chg;
				w->random_offset += chg;
				w->size -= chg;
				continue;
			}
		}
		prev = &w->next;
		w = w->next;
	}
	if (!inserted)
		*prev = new_write;
	/* Update file length */
	if (end > file->length)
		file->length = end;
}

/* Randomly select offset and and size to write in a file */
static void get_offset_and_size(struct file_info *file,
				off_t *offset,
				size_t *size)
{
	size_t r, n;

	r = tests_random_no(100);
	if (r == 0 && grow)
		/* 1 time in 100, when growing, write off the end of the file */
		*offset = file->length + tests_random_no(10000000);
	else if (r < 4)
		/* 3 (or 4) times in 100, write at the beginning of file */
		*offset = 0;
	else if (r < 52 || !grow)
		/* 48 times in 100, write into the file */
		*offset = tests_random_no(file->length);
	else
		/* 48 times in 100, write at the end of the  file */
		*offset = file->length;
	/* Distribute the size logarithmically */
	if (tests_random_no(1000) == 0)
		r = tests_random_no(log10_initial_free_space + 2);
	else
		r = tests_random_no(log10_initial_free_space);
	n = 1;
	while (r--)
		n *= 10;
	*size = tests_random_no(n);
	if (!grow && *offset + *size > file->length)
		*size = file->length - *offset;
	if (*size == 0)
		*size = 1;
}

static void file_truncate_info(struct file_info *file, size_t new_length);

static int file_ftruncate(struct file_info *file, int fd, off_t new_length)
{
	if (ftruncate(fd, new_length) == -1) {
		CHECK(errno = ENOSPC);
		file->no_space_error = 1;
		/* Delete errored files */
		if (!check_nospc_files)
			file_delete(file);
		return 0;
	}
	return 1;
}

static void file_mmap_write(struct file_info *file)
{
	size_t write_cnt = 0, r, i, len, size;
	struct write_info *w = file->writes;
	void *addr;
	char *waddr;
	off_t offs, offset;
	unsigned seed;
	uint64_t free_space;
	int fd;
	char *path;

	if (!file->links)
		return;
	free_space = tests_get_free_space();
	if (!free_space)
		return;
	/* Randomly pick a written area of the file */
	if (!w)
		return;
	while (w) {
		write_cnt += 1;
		w = w->next;
	}
	r = tests_random_no(write_cnt);
	w = file->writes;
	for (i = 0; w && w->next && i < r; i++)
		w = w->next;

	offs = (w->offset / mem_page_size) * mem_page_size;
	len = w->size + (w->offset - offs);
	if (len > 1 << 24)
		len = 1 << 24;

	/* Open it */
	path = dir_path(file->links->parent, file->links->name);
	fd = open(path, O_RDWR);
	CHECK(fd != -1);
	free(path);

	/* mmap it */
	addr = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED, fd, offs);
	CHECK(close(fd) != -1);
	CHECK(addr != MAP_FAILED);

	/* Randomly select a part of the mmapped area to write */
	size = tests_random_no(w->size);
	if (size > free_space)
		size = free_space;
	if (size == 0)
		size = 1;
	offset = w->offset + tests_random_no(w->size - size);

	/* Write it */
	seed = tests_random_no(10000000);
	srand(seed);
	waddr = addr + (offset - offs);
	for (i = 0; i < size; i++)
		waddr[i] = rand();

	/* Unmap it */
	CHECK(munmap(addr, len) != -1);

	/* Record what was written */
	file_write_info(file, offset, size, seed);
}

static void file_write(struct file_info *file, int fd)
{
	off_t offset;
	size_t size, actual;
	unsigned seed;
	int truncate = 0;

	if (can_mmap && !full && !file->deleted && tests_random_no(100) == 1) {
		file_mmap_write(file);
		return;
	}

	get_offset_and_size(file, &offset, &size);
	seed = tests_random_no(10000000);
	actual = file_write_data(file, fd, offset, size, seed);

	if (offset + actual <= file->length && shrink)
		/* 1 time in 100, when shrinking
		   truncate after the write */
		if (tests_random_no(100) == 0)
			truncate = 1;

	if (actual != 0)
		file_write_info(file, offset, actual, seed);

	/* Delete errored files */
	if (!check_nospc_files && file->no_space_error) {
		file_delete(file);
		return;
	}

	if (truncate) {
		size_t new_length = offset + actual;
		if (file_ftruncate(file, fd, new_length))
			file_truncate_info(file, new_length);
	}
}

static void file_write_file(struct file_info *file)
{
	int fd;
	char *path;

	path = dir_path(file->links->parent, file->links->name);
	fd = open(path, O_WRONLY);
	CHECK(fd != -1);
	file_write(file, fd);
	CHECK(close(fd) != -1);
	free(path);
}

static void file_truncate_info(struct file_info *file, size_t new_length)
{
	struct write_info *w, **prev, *tmp;
	size_t sz;

	/* Remove / truncate file->writes */
	w = file->writes;
	prev = &file->writes;
	while (w) {
		if (w->offset >= new_length) {
			/* w comes after eof, so remove it */
			*prev = w->next;
			tmp = w;
			w = w->next;
			free(tmp);
			continue;
		}
		if (w->offset + w->size > new_length)
			w->size = new_length - w->offset;
		prev = &w->next;
		w = w->next;
	}
	/* Add an entry in raw_writes for the truncation */
	sz = sizeof(struct write_info);
	w = (struct write_info *) malloc(sz);
	CHECK(w != NULL);
	memset(w, 0, sz);
	w->next = file->raw_writes;
	w->offset = file->length;
	w->random_offset = new_length; /* Abuse random_offset */
	w->trunc = 1;
	file->raw_writes = w;
	/* Update file length */
	file->length = new_length;
}

static void file_truncate(struct file_info *file, int fd)
{
	size_t new_length;

	new_length = tests_random_no(file->length);

	if (file_ftruncate(file, fd, new_length))
		file_truncate_info(file, new_length);
}

static void file_truncate_file(struct file_info *file)
{
	int fd;
	char *path;

	path = dir_path(file->links->parent, file->links->name);
	fd = open(path, O_WRONLY);
	CHECK(fd != -1);
	file_truncate(file, fd);
	CHECK(close(fd) != -1);
	free(path);
}

static void file_close(struct fd_info *fdi)
{
	struct file_info *file;
	struct fd_info *fdp;
	struct fd_info **prev;

	/* Close file */
	CHECK(close(fdi->fd) != -1);
	/* Remove struct fd_info */
	open_file_remove(fdi);
	file = fdi->file;
	prev = &file->fds;
	for (fdp = file->fds; fdp; fdp = fdp->next) {
		if (fdp == fdi) {
			*prev = fdi->next;
			free(fdi);
			if (file->deleted && !file->fds) {
				/* Closing deleted file */
				struct write_info *w, *next;

				w = file->writes;
				while (w) {
					next = w->next;
					free(w);
					w = next;
				}
				free(file->name);
				free(file);
			}
			return;
		}
		prev = &fdp->next;
	}
	CHECK(0); /* Didn't find struct fd_info */
}

static void file_rewrite_data(int fd, struct write_info *w, char *buf)
{
	size_t remains, block;
	ssize_t written;
	off_t r;

	srand(w->random_seed);
	for (r = 0; r < w->random_offset; ++r)
		rand();
	CHECK(lseek(fd, w->offset, SEEK_SET) != (off_t) -1);
	remains = w->size;
	written = BUFFER_SIZE;
	while (remains) {
		/* Fill up buffer with random data */
		if (written < BUFFER_SIZE)
			memmove(buf, buf + written, BUFFER_SIZE - written);
		else
			written = 0;
		for (; written < BUFFER_SIZE; ++written)