test_io.c revision 6d96b00d57d236e2746f8245df6c8ea64abc64c1 
1/*
2 * test_io.c --- This is the Test I/O interface.
3 *
4 * Copyright (C) 1996 Theodore Ts'o.
5 *
6 * %Begin-Header%
7 * This file may be redistributed under the terms of the GNU Public
8 * License.
9 * %End-Header%
10 */
11
12#include <stdio.h>
13#include <string.h>
14#if HAVE_UNISTD_H
15#include <unistd.h>
16#endif
17#include <fcntl.h>
18#include <time.h>
19#if HAVE_SYS_STAT_H
20#include <sys/stat.h>
21#endif
22#if HAVE_SYS_TYPES_H
23#include <sys/types.h>
24#endif
25#ifdef HAVE_SYS_PRCTL_H
26#include <sys/prctl.h>
27#else
28#define PR_GET_DUMPABLE 3
29#endif
30#if (!defined(HAVE_PRCTL) && defined(linux))
31#include <sys/syscall.h>
32#endif
33
34#include "ext2_fs.h"
35#include "ext2fs.h"
36
37/*
38 * For checking structure magic numbers...
39 */
40
41#define EXT2_CHECK_MAGIC(struct, code) \
42	  if ((struct)->magic != (code)) return (code)
43
44struct test_private_data {
45	int	magic;
46	io_channel real;
47	int flags;
48	FILE *outfile;
49	unsigned long block;
50	int read_abort_count, write_abort_count;
51	void (*read_blk)(unsigned long block, int count, errcode_t err);
52	void (*write_blk)(unsigned long block, int count, errcode_t err);
53	void (*set_blksize)(int blksize, errcode_t err);
54	void (*write_byte)(unsigned long block, int count, errcode_t err);
55};
56
57static errcode_t test_open(const char *name, int flags, io_channel *channel);
58static errcode_t test_close(io_channel channel);
59static errcode_t test_set_blksize(io_channel channel, int blksize);
60static errcode_t test_read_blk(io_channel channel, unsigned long block,
61			       int count, void *data);
62static errcode_t test_write_blk(io_channel channel, unsigned long block,
63				int count, const void *data);
64static errcode_t test_flush(io_channel channel);
65static errcode_t test_write_byte(io_channel channel, unsigned long offset,
66				 int count, const void *buf);
67static errcode_t test_set_option(io_channel channel, const char *option,
68				 const char *arg);
69static errcode_t test_get_stats(io_channel channel, io_stats *stats);
70
71
72static struct struct_io_manager struct_test_manager = {
73	EXT2_ET_MAGIC_IO_MANAGER,
74	"Test I/O Manager",
75	test_open,
76	test_close,
77	test_set_blksize,
78	test_read_blk,
79	test_write_blk,
80	test_flush,
81	test_write_byte,
82	test_set_option,
83	test_get_stats,
84};
85
86io_manager test_io_manager = &struct_test_manager;
87
88/*
89 * These global variable can be set by the test program as
90 * necessary *before* calling test_open
91 */
92io_manager test_io_backing_manager = 0;
93void (*test_io_cb_read_blk)
94	(unsigned long block, int count, errcode_t err) = 0;
95void (*test_io_cb_write_blk)
96	(unsigned long block, int count, errcode_t err) = 0;
97void (*test_io_cb_set_blksize)
98	(int blksize, errcode_t err) = 0;
99void (*test_io_cb_write_byte)
100	(unsigned long block, int count, errcode_t err) = 0;
101
102/*
103 * Test flags
104 */
105#define TEST_FLAG_READ			0x01
106#define TEST_FLAG_WRITE			0x02
107#define TEST_FLAG_SET_BLKSIZE		0x04
108#define TEST_FLAG_FLUSH			0x08
109#define TEST_FLAG_DUMP			0x10
110#define TEST_FLAG_SET_OPTION		0x20
111
112static void test_dump_block(io_channel channel,
113			    struct test_private_data *data,
114			    unsigned long block, const void *buf)
115{
116	const unsigned char *cp;
117	FILE *f = data->outfile;
118	int	i;
119	unsigned long	cksum = 0;
120
121	for (i=0, cp = buf; i < channel->block_size; i++, cp++) {
122		cksum += *cp;
123	}
124	fprintf(f, "Contents of block %lu, checksum %08lu: \n", block, cksum);
125	for (i=0, cp = buf; i < channel->block_size; i++, cp++) {
126		if ((i % 16) == 0)
127			fprintf(f, "%04x: ", i);
128		fprintf(f, "%02x%c", *cp, ((i % 16) == 15) ? '\n' : ' ');
129	}
130}
131
132static void test_abort(io_channel channel, unsigned long block)
133{
134	struct test_private_data *data;
135	FILE *f;
136
137	data = (struct test_private_data *) channel->private_data;
138	f = data->outfile;
139	test_flush(channel);
140
141	fprintf(f, "Aborting due to I/O to block %lu\n", block);
142	fflush(f);
143	abort();
144}
145
146static char *safe_getenv(const char *arg)
147{
148	if ((getuid() != geteuid()) || (getgid() != getegid()))
149		return NULL;
150#if HAVE_PRCTL
151	if (prctl(PR_GET_DUMPABLE, 0, 0, 0, 0) == 0)
152		return NULL;
153#else
154#if (defined(linux) && defined(SYS_prctl))
155	if (syscall(SYS_prctl, PR_GET_DUMPABLE, 0, 0, 0, 0) == 0)
156		return NULL;
157#endif
158#endif
159
160#ifdef HAVE___SECURE_GETENV
161	return __secure_getenv(arg);
162#else
163	return getenv(arg);
164#endif
165}
166
167static errcode_t test_open(const char *name, int flags, io_channel *channel)
168{
169	io_channel	io = NULL;
170	struct test_private_data *data = NULL;
171	errcode_t	retval;
172	char		*value;
173
174	if (name == 0)
175		return EXT2_ET_BAD_DEVICE_NAME;
176	retval = ext2fs_get_mem(sizeof(struct struct_io_channel), &io);
177	if (retval)
178		return retval;
179	memset(io, 0, sizeof(struct struct_io_channel));
180	io->magic = EXT2_ET_MAGIC_IO_CHANNEL;
181	retval = ext2fs_get_mem(sizeof(struct test_private_data), &data);
182	if (retval) {
183		retval = EXT2_ET_NO_MEMORY;
184		goto cleanup;
185	}
186	io->manager = test_io_manager;
187	retval = ext2fs_get_mem(strlen(name)+1, &io->name);
188	if (retval)
189		goto cleanup;
190
191	strcpy(io->name, name);
192	io->private_data = data;
193	io->block_size = 1024;
194	io->read_error = 0;
195	io->write_error = 0;
196	io->refcount = 1;
197
198	memset(data, 0, sizeof(struct test_private_data));
199	data->magic = EXT2_ET_MAGIC_TEST_IO_CHANNEL;
200	if (test_io_backing_manager) {
201		retval = test_io_backing_manager->open(name, flags,
202						       &data->real);
203		if (retval)
204			goto cleanup;
205	} else
206		data->real = 0;
207	data->read_blk = 	test_io_cb_read_blk;
208	data->write_blk = 	test_io_cb_write_blk;
209	data->set_blksize = 	test_io_cb_set_blksize;
210	data->write_byte = 	test_io_cb_write_byte;
211
212	data->outfile = NULL;
213	if ((value = safe_getenv("TEST_IO_LOGFILE")) != NULL)
214		data->outfile = fopen(value, "w");
215	if (!data->outfile)
216		data->outfile = stderr;
217
218	data->flags = 0;
219	if ((value = safe_getenv("TEST_IO_FLAGS")) != NULL)
220		data->flags = strtoul(value, NULL, 0);
221
222	data->block = 0;
223	if ((value = safe_getenv("TEST_IO_BLOCK")) != NULL)
224		data->block = strtoul(value, NULL, 0);
225
226	data->read_abort_count = 0;
227	if ((value = safe_getenv("TEST_IO_READ_ABORT")) != NULL)
228		data->read_abort_count = strtoul(value, NULL, 0);
229
230	data->write_abort_count = 0;
231	if ((value = safe_getenv("TEST_IO_WRITE_ABORT")) != NULL)
232		data->write_abort_count = strtoul(value, NULL, 0);
233
234	*channel = io;
235	return 0;
236
237cleanup:
238	if (io)
239		ext2fs_free_mem(&io);
240	if (data)
241		ext2fs_free_mem(&data);
242	return retval;
243}
244
245static errcode_t test_close(io_channel channel)
246{
247	struct test_private_data *data;
248	errcode_t	retval = 0;
249
250	EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
251	data = (struct test_private_data *) channel->private_data;
252	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_TEST_IO_CHANNEL);
253
254	if (--channel->refcount > 0)
255		return 0;
256
257	if (data->real)
258		retval = io_channel_close(data->real);
259
260	if (data->outfile && data->outfile != stderr)
261		fclose(data->outfile);
262
263	ext2fs_free_mem(&channel->private_data);
264	if (channel->name)
265		ext2fs_free_mem(&channel->name);
266	ext2fs_free_mem(&channel);
267	return retval;
268}
269
270static errcode_t test_set_blksize(io_channel channel, int blksize)
271{
272	struct test_private_data *data;
273	errcode_t	retval = 0;
274
275	EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
276	data = (struct test_private_data *) channel->private_data;
277	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_TEST_IO_CHANNEL);
278
279	if (data->real)
280		retval = io_channel_set_blksize(data->real, blksize);
281	if (data->set_blksize)
282		data->set_blksize(blksize, retval);
283	if (data->flags & TEST_FLAG_SET_BLKSIZE)
284		fprintf(data->outfile,
285			"Test_io: set_blksize(%d) returned %s\n",
286			blksize, retval ? error_message(retval) : "OK");
287	channel->block_size = blksize;
288	return retval;
289}
290
291
292static errcode_t test_read_blk(io_channel channel, unsigned long block,
293			       int count, void *buf)
294{
295	struct test_private_data *data;
296	errcode_t	retval = 0;
297
298	EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
299	data = (struct test_private_data *) channel->private_data;
300	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_TEST_IO_CHANNEL);
301
302	if (data->real)
303		retval = io_channel_read_blk(data->real, block, count, buf);
304	if (data->read_blk)
305		data->read_blk(block, count, retval);
306	if (data->flags & TEST_FLAG_READ)
307		fprintf(data->outfile,
308			"Test_io: read_blk(%lu, %d) returned %s\n",
309			block, count, retval ? error_message(retval) : "OK");
310	if (data->block && data->block == block) {
311		if (data->flags & TEST_FLAG_DUMP)
312			test_dump_block(channel, data, block, buf);
313		if (--data->read_abort_count == 0)
314			test_abort(channel, block);
315	}
316	return retval;
317}
318
319static errcode_t test_write_blk(io_channel channel, unsigned long block,
320			       int count, const void *buf)
321{
322	struct test_private_data *data;
323	errcode_t	retval = 0;
324
325	EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
326	data = (struct test_private_data *) channel->private_data;
327	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_TEST_IO_CHANNEL);
328
329	if (data->real)
330		retval = io_channel_write_blk(data->real, block, count, buf);
331	if (data->write_blk)
332		data->write_blk(block, count, retval);
333	if (data->flags & TEST_FLAG_WRITE)
334		fprintf(data->outfile,
335			"Test_io: write_blk(%lu, %d) returned %s\n",
336			block, count, retval ? error_message(retval) : "OK");
337	if (data->block && data->block == block) {
338		if (data->flags & TEST_FLAG_DUMP)
339			test_dump_block(channel, data, block, buf);
340		if (--data->write_abort_count == 0)
341			test_abort(channel, block);
342	}
343	return retval;
344}
345
346static errcode_t test_write_byte(io_channel channel, unsigned long offset,
347			       int count, const void *buf)
348{
349	struct test_private_data *data;
350	errcode_t	retval = 0;
351
352	EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
353	data = (struct test_private_data *) channel->private_data;
354	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_TEST_IO_CHANNEL);
355
356	if (data->real && data->real->manager->write_byte)
357		retval = io_channel_write_byte(data->real, offset, count, buf);
358	if (data->write_byte)
359		data->write_byte(offset, count, retval);
360	if (data->flags & TEST_FLAG_WRITE)
361		fprintf(data->outfile,
362			"Test_io: write_byte(%lu, %d) returned %s\n",
363			offset, count, retval ? error_message(retval) : "OK");
364	return retval;
365}
366
367/*
368 * Flush data buffers to disk.
369 */
370static errcode_t test_flush(io_channel channel)
371{
372	struct test_private_data *data;
373	errcode_t	retval = 0;
374
375	EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
376	data = (struct test_private_data *) channel->private_data;
377	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_TEST_IO_CHANNEL);
378
379	if (data->real)
380		retval = io_channel_flush(data->real);
381
382	if (data->flags & TEST_FLAG_FLUSH)
383		fprintf(data->outfile, "Test_io: flush() returned %s\n",
384			retval ? error_message(retval) : "OK");
385
386	return retval;
387}
388
389static errcode_t test_set_option(io_channel channel, const char *option,
390				 const char *arg)
391{
392	struct test_private_data *data;
393	errcode_t	retval = 0;
394
395	EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
396	data = (struct test_private_data *) channel->private_data;
397	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_TEST_IO_CHANNEL);
398
399
400	if (data->flags & TEST_FLAG_SET_OPTION)
401		fprintf(data->outfile, "Test_io: set_option(%s, %s) ",
402			option, arg);
403	if (data->real && data->real->manager->set_option) {
404		retval = (data->real->manager->set_option)(data->real,
405							   option, arg);
406		if (data->flags & TEST_FLAG_SET_OPTION)
407			fprintf(data->outfile, "returned %s\n",
408				retval ? error_message(retval) : "OK");
409	} else {
410		if (data->flags & TEST_FLAG_SET_OPTION)
411			fprintf(data->outfile, "not implemented\n");
412	}
413	return retval;
414}
415
416static errcode_t test_get_stats(io_channel channel, io_stats *stats)
417{
418	struct test_private_data *data;
419	errcode_t	retval = 0;
420
421	EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
422	data = (struct test_private_data *) channel->private_data;
423	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_TEST_IO_CHANNEL);
424
425	if (data->real && data->real->manager->get_stats) {
426		retval = (data->real->manager->get_stats)(data->real, stats);
427	}
428	return retval;
429}
430