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Revision 4b3be6afa4ab8b3fdce39df68bad71f8b85164de authored by Julia Lawall on 17 October 2009, 06:33:22 UTC, committed by Takashi Iwai on 30 October 2009, 11:01:27 UTC 
ALSA: sound: Move dereference after NULL test and drop unnecessary NULL tests
 
In pcm.c, if the NULL test on pcm is needed, then the dereference should be
after the NULL test.

In dummy.c and ali5451.c, the context of the calls to
snd_card_dummy_new_mixer and snd_ali_free_voice show that dummy and pvoice,
respectively cannot be NULL.

A simplified version of the semantic match that detects this problem is as
follows (http://coccinelle.lip6.fr/):

// <smpl>
@match exists@
expression x, E;
identifier fld;
@@

* x->fld
  ... when != \(x = E\|&x\)
* x == NULL
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
1 parent b71207e
Raw File
crc7.c 
/*
 *      crc7.c
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2. See the file COPYING for more details.
 */

#include <linux/types.h>
#include <linux/module.h>
#include <linux/crc7.h>


/* Table for CRC-7 (polynomial x^7 + x^3 + 1) */
const u8 crc7_syndrome_table[256] = {
	0x00, 0x09, 0x12, 0x1b, 0x24, 0x2d, 0x36, 0x3f,
	0x48, 0x41, 0x5a, 0x53, 0x6c, 0x65, 0x7e, 0x77,
	0x19, 0x10, 0x0b, 0x02, 0x3d, 0x34, 0x2f, 0x26,
	0x51, 0x58, 0x43, 0x4a, 0x75, 0x7c, 0x67, 0x6e,
	0x32, 0x3b, 0x20, 0x29, 0x16, 0x1f, 0x04, 0x0d,
	0x7a, 0x73, 0x68, 0x61, 0x5e, 0x57, 0x4c, 0x45,
	0x2b, 0x22, 0x39, 0x30, 0x0f, 0x06, 0x1d, 0x14,
	0x63, 0x6a, 0x71, 0x78, 0x47, 0x4e, 0x55, 0x5c,
	0x64, 0x6d, 0x76, 0x7f, 0x40, 0x49, 0x52, 0x5b,
	0x2c, 0x25, 0x3e, 0x37, 0x08, 0x01, 0x1a, 0x13,
	0x7d, 0x74, 0x6f, 0x66, 0x59, 0x50, 0x4b, 0x42,
	0x35, 0x3c, 0x27, 0x2e, 0x11, 0x18, 0x03, 0x0a,
	0x56, 0x5f, 0x44, 0x4d, 0x72, 0x7b, 0x60, 0x69,
	0x1e, 0x17, 0x0c, 0x05, 0x3a, 0x33, 0x28, 0x21,
	0x4f, 0x46, 0x5d, 0x54, 0x6b, 0x62, 0x79, 0x70,
	0x07, 0x0e, 0x15, 0x1c, 0x23, 0x2a, 0x31, 0x38,
	0x41, 0x48, 0x53, 0x5a, 0x65, 0x6c, 0x77, 0x7e,
	0x09, 0x00, 0x1b, 0x12, 0x2d, 0x24, 0x3f, 0x36,
	0x58, 0x51, 0x4a, 0x43, 0x7c, 0x75, 0x6e, 0x67,
	0x10, 0x19, 0x02, 0x0b, 0x34, 0x3d, 0x26, 0x2f,
	0x73, 0x7a, 0x61, 0x68, 0x57, 0x5e, 0x45, 0x4c,
	0x3b, 0x32, 0x29, 0x20, 0x1f, 0x16, 0x0d, 0x04,
	0x6a, 0x63, 0x78, 0x71, 0x4e, 0x47, 0x5c, 0x55,
	0x22, 0x2b, 0x30, 0x39, 0x06, 0x0f, 0x14, 0x1d,
	0x25, 0x2c, 0x37, 0x3e, 0x01, 0x08, 0x13, 0x1a,
	0x6d, 0x64, 0x7f, 0x76, 0x49, 0x40, 0x5b, 0x52,
	0x3c, 0x35, 0x2e, 0x27, 0x18, 0x11, 0x0a, 0x03,
	0x74, 0x7d, 0x66, 0x6f, 0x50, 0x59, 0x42, 0x4b,
	0x17, 0x1e, 0x05, 0x0c, 0x33, 0x3a, 0x21, 0x28,
	0x5f, 0x56, 0x4d, 0x44, 0x7b, 0x72, 0x69, 0x60,
	0x0e, 0x07, 0x1c, 0x15, 0x2a, 0x23, 0x38, 0x31,
	0x46, 0x4f, 0x54, 0x5d, 0x62, 0x6b, 0x70, 0x79
};
EXPORT_SYMBOL(crc7_syndrome_table);

/**
 * crc7 - update the CRC7 for the data buffer
 * @crc:     previous CRC7 value
 * @buffer:  data pointer
 * @len:     number of bytes in the buffer
 * Context: any
 *
 * Returns the updated CRC7 value.
 */
u8 crc7(u8 crc, const u8 *buffer, size_t len)
{
	while (len--)
		crc = crc7_byte(crc, *buffer++);
	return crc;
}
EXPORT_SYMBOL(crc7);

MODULE_DESCRIPTION("CRC7 calculations");
MODULE_LICENSE("GPL");
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