integck.c

mtd-utils 是一套更改linux mtd設備的工具

/*
 * Copyright (C) 2007 Nokia Corporation.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 *
 * Author: Adrian Hunter
 */

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <limits.h>
#include <dirent.h>
#include <sys/mman.h>

#include "tests.h"

/* Structures to store data written to the test file system,
   so that we can check whether the file system is correct. */

struct write_info /* Record of random data written into a file */
{
	struct write_info *next;
	off_t offset; /* Where in the file the data was written */
	size_t size; /* Number of bytes written */
	unsigned random_seed; /* Seed for rand() to create random data */
	off_t random_offset; /* Call rand() this number of times first */
	int trunc; /* Records a truncation (raw_writes only) */
};

struct dir_entry_info;

struct file_info /* Each file has one of these */
{
	char *name; /* Original name */
	struct write_info *writes; /* Record accumulated writes to the file */
	struct write_info *raw_writes;
				/* Record in order all writes to the file */
	struct fd_info *fds; /* All open file descriptors for this file */
	struct dir_entry_info *links;
	int link_count;
	off_t length;
	int deleted; /* File has been deleted but is still open */
	int no_space_error; /* File has incurred a ENOSPC error */
	uint64_t check_run_no; /* Run number used when checking */
};

struct symlink_info /* Each symlink has one of these */
{
	char *target_pathname;
	struct dir_entry_info *entry; /* dir entry of this symlink */
};

struct dir_info /* Each directory has one of these */
{
	char *name;
	struct dir_info *parent; /* Parent directory or null
					for our top directory */
	unsigned number_of_entries;
	struct dir_entry_info *first;
	struct dir_entry_info *entry; /* Dir entry of this dir */
};

struct dir_entry_info /* Each entry in a directory has one of these */
{
	struct dir_entry_info *next; /* List of entries in directory */
	struct dir_entry_info *prev; /* List of entries in directory */
	struct dir_entry_info *next_link; /* List of hard links for same file */
	struct dir_entry_info *prev_link; /* List of hard links for same file */
	char *name;
	struct dir_info *parent; /* Parent directory */
	char type; /* f => file, d => dir, s => symlink */
	int checked; /* Temporary flag used when checking */
	union entry_
	{
		struct file_info *file;
		struct dir_info *dir;
		struct symlink_info *symlink;
		void *target;
	} entry;
};

struct fd_info /* We keep a number of files open */
{
	struct fd_info *next;
	struct file_info *file;
	int fd;
};

struct open_file_info /* We keep a list of open files */
{
	struct open_file_info *next;
	struct fd_info *fdi;
};

static struct dir_info *top_dir = NULL; /* Our top directory */

static struct open_file_info *open_files = NULL; /* We keep a list of
							open files */
static size_t open_files_count = 0;

static int grow   = 1; /* Should we try to grow files and directories */
static int shrink = 0; /* Should we try to shrink files and directories */
static int full   = 0; /* Flag that the file system is full */
static uint64_t operation_count = 0; /* Number of operations used to fill
                                        up the file system */
static uint64_t initial_free_space = 0; /* Free space on file system when
					   test starts */
static unsigned log10_initial_free_space = 0; /* log10 of initial_free_space */

static int check_nospc_files = 0; /* Also check data in files that incurred a
				     "no space" error */

static int can_mmap = 0; /* Can write via mmap */

static long mem_page_size; /* Page size for mmap */

static uint64_t check_run_no;

static char *copy_string(const char *s)
{
	char *str;

	if (!s)
		return NULL;
	str = (char *) malloc(strlen(s) + 1);
	CHECK(str != NULL);
	strcpy(str, s);
	return str;
}

static char *cat_strings(const char *a, const char *b)
{
	char *str;
	size_t sz;

	if (a && !b)
		return copy_string(a);
	if (b && !a)
		return copy_string(b);
	if (!a && !b)
		return NULL;
	sz = strlen(a) + strlen(b) + 1;
	str = (char *) malloc(sz);
	CHECK(str != NULL);
	strcpy(str, a);
	strcat(str, b);
	return str;
}

static char *cat_paths(const char *a, const char *b)
{
	char *str;
	size_t sz;
	int as, bs;
	size_t na, nb;

	if (a && !b)
		return copy_string(a);
	if (b && !a)
		return copy_string(b);
	if (!a && !b)
		return NULL;

	as = 0;
	bs = 0;
	na = strlen(a);
	nb = strlen(b);
	if (na && a[na - 1] == '/')
		as = 1;
	if (nb && b[0] == '/')
		bs = 1;
	if ((as && !bs) || (!as && bs))
		return cat_strings(a, b);
	if (as && bs)
		return cat_strings(a, b + 1);

	sz = na + nb + 2;
	str = (char *) malloc(sz);
	CHECK(str != NULL);
	strcpy(str, a);
	strcat(str, "/");
	strcat(str, b);
	return str;
}

static char *dir_path(struct dir_info *parent, const char *name)
{
	char *parent_path;
	char *path;

	if (!parent)
		return cat_paths(tests_file_system_mount_dir, name);
	parent_path = dir_path(parent->parent, parent->name);
	path = cat_paths(parent_path, name);
	free(parent_path);
	return path;
}

static void open_file_add(struct fd_info *fdi)
{
	struct open_file_info *ofi;
	size_t sz;

	sz = sizeof(struct open_file_info);
	ofi = (struct open_file_info *) malloc(sz);
	CHECK(ofi != NULL);
	memset(ofi, 0, sz);
	ofi->next = open_files;
	ofi->fdi = fdi;
	open_files = ofi;
	open_files_count += 1;
}

static void open_file_remove(struct fd_info *fdi)
{
	struct open_file_info *ofi;
	struct open_file_info **prev;

	prev = &open_files;
	for (ofi = open_files; ofi; ofi = ofi->next) {
		if (ofi->fdi == fdi) {
			*prev = ofi->next;
			free(ofi);
			open_files_count -= 1;
			return;
		}
		prev = &ofi->next;
	}
	CHECK(0); /* We are trying to remove something that is not there */
}

static struct fd_info *add_fd(struct file_info *file, int fd)
{
	struct fd_info *fdi;
	size_t sz;

	sz = sizeof(struct fd_info);
	fdi = (struct fd_info *) malloc(sz);
	CHECK(fdi != NULL);
	memset(fdi, 0, sz);
	fdi->next = file->fds;
	fdi->file = file;
	fdi->fd = fd;
	file->fds = fdi;
	open_file_add(fdi);
	return fdi;
}

static void add_dir_entry(struct dir_info *parent, char type, const char *name,
			  void *target)
{
	struct dir_entry_info *entry;
	size_t sz;

	sz = sizeof(struct dir_entry_info);
	entry = (struct dir_entry_info *) malloc(sz);
	CHECK(entry != NULL);
	memset(entry, 0, sz);

	entry->type = type;
	entry->name = copy_string(name);
	entry->parent = parent;

	entry->next = parent->first;
	if (parent->first)
		parent->first->prev = entry;
	parent->first = entry;
	parent->number_of_entries += 1;

	if (entry->type == 'f') {
		struct file_info *file = target;

		entry->entry.file = file;
		entry->next_link = file->links;
		if (file->links)
			file->links->prev_link = entry;
		file->links = entry;
		file->link_count += 1;
	} else if (entry->type == 'd') {
		struct dir_info *dir = target;

		entry->entry.dir = dir;
		dir->entry = entry;
		dir->name = copy_string(name);
		dir->parent = parent;
	} else if (entry->type == 's') {
		struct symlink_info *symlink = target;

		entry->entry.symlink = symlink;
		symlink->entry = entry;
	}
}

static void remove_dir_entry(struct dir_entry_info *entry)
{
	entry->parent->number_of_entries -= 1;
	if (entry->parent->first == entry)
		entry->parent->first = entry->next;
	if (entry->prev)
		entry->prev->next = entry->next;
	if (entry->next)
		entry->next->prev = entry->prev;

	if (entry->type == 'f') {
		struct file_info *file = entry->entry.file;

		if (entry->prev_link)
			entry->prev_link->next_link = entry->next_link;
		if (entry->next_link)
			entry->next_link->prev_link = entry->prev_link;
		if (file->links == entry)
			file->links = entry->next_link;
		file->link_count -= 1;
		if (file->link_count == 0)
			file->deleted = 1;
	}

	free(entry->name);
	free(entry);
}

static struct dir_info *dir_new(struct dir_info *parent, const char *name)
{
	struct dir_info *dir;
	size_t sz;
	char *path;

	path = dir_path(parent, name);
	if (mkdir(path, 0777) == -1) {
		CHECK(errno == ENOSPC);
		full = 1;
		free(path);
		return NULL;
	}
	free(path);

	sz = sizeof(struct dir_info);
	dir = (struct dir_info *) malloc(sz);
	CHECK(dir != NULL);
	memset(dir, 0, sz);
	dir->name = copy_string(name);
	dir->parent = parent;
	if (parent)
		add_dir_entry(parent, 'd', name, dir);
	return dir;
}

static void file_delete(struct file_info *file);
static void file_unlink(struct dir_entry_info *entry);
static void symlink_remove(struct symlink_info *symlink);

static void dir_remove(struct dir_info *dir)
{
	char *path;

	/* Remove directory contents */
	while (dir->first) {
		struct dir_entry_info *entry;

		entry = dir->first;
		if (entry->type == 'd')
			dir_remove(entry->entry.dir);
		else if (entry->type == 'f')
			file_unlink(entry);
		else if (entry->type == 's')
			symlink_remove(entry->entry.symlink);
		else
			CHECK(0); /* Invalid struct dir_entry_info */
	}
	/* Remove entry from parent directory */
	remove_dir_entry(dir->entry);
	/* Remove directory itself */
	path = dir_path(dir->parent, dir->name);
	CHECK(rmdir(path) != -1);
	free(dir);
}

static struct file_info *file_new(struct dir_info *parent, const char *name)
{
	struct file_info *file = NULL;
	char *path;
	mode_t mode;
	int fd;
	size_t sz;

	CHECK(parent != NULL);

	path = dir_path(parent, name);
	mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH;
	fd = open(path, O_CREAT | O_EXCL | O_RDWR, mode);
	if (fd == -1) {
		CHECK(errno == ENOSPC);
		free(path);
		full = 1;
		return NULL;
	}
	free(path);

	sz = sizeof(struct file_info);
	file = (struct file_info *) malloc(sz);
	CHECK(file != NULL);
	memset(file, 0, sz);
	file->name = copy_string(name);

	add_dir_entry(parent, 'f', name, file);

	add_fd(file, fd);

	return file;
}

static void link_new(struct dir_info *parent, const char *name,
		     struct file_info *file)
{
	struct dir_entry_info *entry;
	char *path, *target;
	int ret;

	if (!file)
		return;
	entry = file->links;
	if (!entry)
		return;
	path = dir_path(parent, name);
	target = dir_path(entry->parent, entry->name);
	ret = link(target, path);
	if (ret == -1) {
		CHECK(errno == ENOSPC);
		free(target);
		free(path);
		full = 1;
		return;
	}
	free(target);
	free(path);

	add_dir_entry(parent, 'f', name, file);
}

static void file_close(struct fd_info *fdi);

static void file_close_all(struct file_info *file)
{
	struct fd_info *fdi = file->fds;

	while (fdi) {
		struct fd_info *next = fdi->next;

		file_close(fdi);
		fdi = next;
	}
}

static void file_unlink(struct dir_entry_info *entry)
{
	struct file_info *file = entry->entry.file;
	char *path;

	path = dir_path(entry->parent, entry->name);

	/* Remove file entry from parent directory */
	remove_dir_entry(entry);

	/* Unlink the file */
	CHECK(unlink(path) != -1);
	free(path);

	/* Free struct file_info if file is not open and not linked */
	if (!file->fds && !file->links) {
		struct write_info *w, *next;

		free(file->name);
		w = file->writes;
		while (w) {
			next = w->next;
			free(w);
			w = next;
		}
		free(file);
	} else if (!file->links)
		file->deleted = 1;
}

static struct dir_entry_info *pick_entry(struct file_info *file)
{
	struct dir_entry_info *entry;
	size_t r;

	if (!file->link_count)
		return NULL;
	r = tests_random_no(file->link_count);
	entry = file->links;
	while (entry && r--)
		entry = entry->next_link;
	return entry;
}

static void file_unlink_file(struct file_info *file)