Differential D19706 Diff 55928 sys/kern/subr_compressor.c

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sys/kern/subr_compressor.c

Show First 20 Lines • Show All 60 Lines • ▼ Show 20 Lines	struct compressor {
void *priv;		void *priv;
void *arg;		void *arg;
};		};

SET_DECLARE(compressors, struct compressor_methods);		SET_DECLARE(compressors, struct compressor_methods);

#ifdef GZIO		#ifdef GZIO

#include <sys/zutil.h>		#include <sys/crc32.h>
		#include <zlib.h>
		sobomaxUnsubmitted Done Inline Actions Do we really need that comment? It's pretty clear (to me anyway), why do we need to include zlib.h. I have not seen us doing this for any other headers used in the kernel. sobomax: Do we really need that comment? It's pretty clear (to me anyway), why do we need to include…
		ota_j.email.ne.jpUnsubmitted Done Inline Actions I will clean up later. I had to keep my note while trying to replace from old header to new header and one file to another. ota_j.email.ne.jp: I will clean up later. I had to keep my note while trying to replace from old header to new…

struct gz_stream {		struct gz_stream {
uint8_t gz_buffer; / output buffer */		uint8_t gz_buffer; / output buffer */
size_t gz_bufsz; /* output buffer size */		size_t gz_bufsz; /* output buffer size */
off_t gz_off; /* offset into the output stream */		off_t gz_off; /* offset into the output stream */
uint32_t gz_crc; /* stream CRC32 */		uint32_t gz_crc; /* stream CRC32 */
z_stream gz_stream; /* zlib state */		z_stream gz_stream; /* zlib state */
};		};

static void *gz_init(size_t maxiosize, int level);		static void *gz_init(size_t maxiosize, int level);
static void gz_reset(void *stream);		static void gz_reset(void *stream);
static int gz_write(void stream, void data, size_t len, compressor_cb_t,		static int gz_write(void stream, void data, size_t len, compressor_cb_t,
void *);		void *);
static void gz_fini(void *stream);		static void gz_fini(void *stream);

static void *		static void *
gz_alloc(void *arg __unused, u_int n, u_int sz)		gz_alloc(void *arg __unused, u_int n, u_int sz)
{		{

/*		/*
* Memory for zlib state is allocated using M_NODUMP since it may be		* Memory for zlib state is allocated using M_NODUMP since it may be
* used to compress a kernel dump, and we don't want zlib to attempt to		* used to compress a kernel dump, and we don't want zlib to attempt to
* compress its own state.		* compress its own state.
*/		*/
return (malloc(n * sz, M_COMPRESS, M_WAITOK \| M_ZERO \| M_NODUMP));		return (malloc(n * sz, M_COMPRESS, M_WAITOK \| M_ZERO \| M_NODUMP)); /* HIRO - why this one is okay with M_WAITOK unlike others */
}		}

static void		static void
gz_free(void arg __unused, void ptr)		gz_free(void arg __unused, void ptr)
{		{

free(ptr, M_COMPRESS);		free(ptr, M_COMPRESS);
}		}
Show All 9 Lines	gz_init(size_t maxiosize, int level)
s->gz_bufsz = maxiosize;		s->gz_bufsz = maxiosize;

s->gz_stream.zalloc = gz_alloc;		s->gz_stream.zalloc = gz_alloc;
s->gz_stream.zfree = gz_free;		s->gz_stream.zfree = gz_free;
s->gz_stream.opaque = NULL;		s->gz_stream.opaque = NULL;
s->gz_stream.next_in = Z_NULL;		s->gz_stream.next_in = Z_NULL;
s->gz_stream.avail_in = 0;		s->gz_stream.avail_in = 0;

error = deflateInit2(&s->gz_stream, level, Z_DEFLATED, -MAX_WBITS,		error = z_deflateInit2(&s->gz_stream, level, Z_DEFLATED, -MAX_WBITS,
DEF_MEM_LEVEL, Z_DEFAULT_STRATEGY);		8 /* as DEF_MEM_LEVEL */, Z_DEFAULT_STRATEGY);
		delphijAuthorUnsubmitted Not Done Inline Actions Optional: personally I think it's fine to just use 8 here - there is little reason to tweak it anyways, and the example application shipped with zlib use a hardcoded 8 too. delphij: Optional: personally I think it's fine to just use 8 here - there is little reason to tweak it…
		ota_j.email.ne.jpUnsubmitted Done Inline Actions zlib.h doesn't expose this DEF_MEM_LEVEL and wondered how other people would think by changing to const value. Should I keep the comment or remove it? ota_j.email.ne.jp: zlib.h doesn't expose this DEF_MEM_LEVEL and wondered how other people would think by changing…
if (error != 0)		if (error != 0)
goto fail;		goto fail;

gz_reset(s);		gz_reset(s);

return (s);		return (s);

fail:		fail:
gz_free(NULL, s);		gz_free(NULL, s);
return (NULL);		return (NULL);
}		}

static void		static void
gz_reset(void *stream)		gz_reset(void *stream)
{		{
struct gz_stream *s;		struct gz_stream *s;
uint8_t *hdr;		uint8_t *hdr;
const size_t hdrlen = 10;		const size_t hdrlen = 10;

s = stream;		s = stream;
s->gz_off = 0;		s->gz_off = 0;
s->gz_crc = ~0U;		s->gz_crc = ~0U;

(void)deflateReset(&s->gz_stream);		(void)z_deflateReset(&s->gz_stream);
s->gz_stream.avail_out = s->gz_bufsz;		s->gz_stream.avail_out = s->gz_bufsz;
s->gz_stream.next_out = s->gz_buffer;		s->gz_stream.next_out = s->gz_buffer;

/* Write the gzip header to the output buffer. */		/* Write the gzip header to the output buffer. */
hdr = s->gz_buffer;		hdr = s->gz_buffer;
memset(hdr, 0, hdrlen);		memset(hdr, 0, hdrlen);
hdr[0] = 0x1f;		hdr[0] = 0x1f;
hdr[1] = 0x8b;		hdr[1] = 0x8b;
hdr[2] = Z_DEFLATED;		hdr[2] = Z_DEFLATED;
hdr[9] = OS_CODE;		hdr[9] = 0x03; /* zlib's OS_CODE Unix */
s->gz_stream.next_out += hdrlen;		s->gz_stream.next_out += hdrlen;
s->gz_stream.avail_out -= hdrlen;		s->gz_stream.avail_out -= hdrlen;
}		}

static int		static int
gz_write(void stream, void data, size_t len, compressor_cb_t cb,		gz_write(void stream, void data, size_t len, compressor_cb_t cb,
void *arg)		void *arg)
{		{
Show All 9 Lines	if (len > 0) {
s->gz_stream.avail_in = len;		s->gz_stream.avail_in = len;
s->gz_stream.next_in = data;		s->gz_stream.next_in = data;
s->gz_crc = crc32_raw(data, len, s->gz_crc);		s->gz_crc = crc32_raw(data, len, s->gz_crc);
} else		} else
s->gz_crc ^= ~0U;		s->gz_crc ^= ~0U;

error = 0;		error = 0;
do {		do {
zerror = deflate(&s->gz_stream, zflag);		zerror = z_deflate(&s->gz_stream, zflag);
if (zerror != Z_OK && zerror != Z_STREAM_END) {		if (zerror != Z_OK && zerror != Z_STREAM_END) {
error = EIO;		error = EIO;
break;		break;
}		}

if (s->gz_stream.avail_out == 0 \|\| zerror == Z_STREAM_END) {		if (s->gz_stream.avail_out == 0 \|\| zerror == Z_STREAM_END) {
/*		/*
* Our output buffer is full or there's nothing left		* Our output buffer is full or there's nothing left
Show All 37 Lines
}		}

static void		static void
gz_fini(void *stream)		gz_fini(void *stream)
{		{
struct gz_stream *s;		struct gz_stream *s;

s = stream;		s = stream;
(void)deflateEnd(&s->gz_stream);		(void)z_deflateEnd(&s->gz_stream);
gz_free(NULL, s->gz_buffer);		gz_free(NULL, s->gz_buffer);
gz_free(NULL, s);		gz_free(NULL, s);
}		}

struct compressor_methods gzip_methods = {		struct compressor_methods gzip_methods = {
.format = COMPRESS_GZIP,		.format = COMPRESS_GZIP,
.init = gz_init,		.init = gz_init,
.reset = gz_reset,		.reset = gz_reset,
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