patch-2.1.132 linux/net/irda/compressors/irda_deflate.c
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- Lines: 636
- Date:
Fri Dec 18 08:06:39 1998
- Orig file:
v2.1.131/linux/net/irda/compressors/irda_deflate.c
- Orig date:
Wed Dec 31 16:00:00 1969
diff -u --recursive --new-file v2.1.131/linux/net/irda/compressors/irda_deflate.c linux/net/irda/compressors/irda_deflate.c
@@ -0,0 +1,635 @@
+/*********************************************************************
+ *
+ * Filename: irda_deflate.c
+ * Version:
+ * Description:
+ * Status: Experimental.
+ * Author: Dag Brattli <dagb@cs.uit.no>
+ * Created at: Fri Oct 9 02:52:08 1998
+ * Modified at: Mon Dec 14 19:48:54 1998
+ * Modified by: Dag Brattli <dagb@cs.uit.no>
+ *
+ * ==FILEVERSION 980319==
+ *
+ * irda_deflate.c - interface the zlib procedures for Deflate compression
+ * and decompression (as used by gzip) to the IrDA code.
+ * This version is for use with Linux kernel 2.1.X.
+ *
+ * Copyright (c) 1994 The Australian National University.
+ * All rights reserved.
+ *
+ * Permission to use, copy, modify, and distribute this software and its
+ * documentation is hereby granted, provided that the above copyright
+ * notice appears in all copies. This software is provided without any
+ * warranty, express or implied. The Australian National University
+ * makes no representations about the suitability of this software for
+ * any purpose.
+ *
+ * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
+ * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
+ * THE AUSTRALIAN NATIONAL UNIVERSITY HAS BEEN ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
+ * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
+ * OR MODIFICATIONS.
+ *
+ * From: deflate.c,v 1.1 1996/01/18 03:17:48 paulus Exp
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/ptrace.h>
+#include <linux/ioport.h>
+#include <linux/in.h>
+#include <linux/malloc.h>
+#include <linux/vmalloc.h>
+#include <linux/errno.h>
+#include <linux/sched.h> /* to get the struct task_struct */
+#include <linux/string.h> /* used in new tty drivers */
+#include <linux/signal.h> /* used in new tty drivers */
+
+#include <asm/system.h>
+
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/inet.h>
+#include <linux/ioctl.h>
+
+#include <linux/ppp_defs.h>
+#include <linux/ppp-comp.h>
+
+/*
+ * This is not that nice, but what can we do when the code has been placed
+ * elsewhere
+ */
+
+#include "../../../drivers/net/zlib.c"
+
+/*
+ * State for a Deflate (de)compressor.
+ */
+struct irda_deflate_state {
+ int seqno;
+ int w_size;
+ int unit;
+ int mru;
+ int debug;
+ z_stream strm;
+ struct compstat stats;
+};
+
+#define DEFLATE_OVHD 2 /* Deflate overhead/packet */
+
+static void *zalloc __P((void *, unsigned int items, unsigned int size));
+static void *zalloc_init __P((void *, unsigned int items,
+ unsigned int size));
+static void zfree __P((void *, void *ptr));
+static void *z_comp_alloc __P((unsigned char *options, int opt_len));
+static void *z_decomp_alloc __P((unsigned char *options, int opt_len));
+static void z_comp_free __P((void *state));
+static void z_decomp_free __P((void *state));
+static int z_comp_init __P((void *state, unsigned char *options,
+ int opt_len,
+ int unit, int hdrlen, int debug));
+static int z_decomp_init __P((void *state, unsigned char *options,
+ int opt_len,
+ int unit, int hdrlen, int mru, int debug));
+static int z_compress __P((void *state, unsigned char *rptr,
+ unsigned char *obuf,
+ int isize, int osize));
+static void z_incomp __P((void *state, unsigned char *ibuf, int icnt));
+static int z_decompress __P((void *state, unsigned char *ibuf,
+ int isize, unsigned char *obuf, int osize));
+static void z_comp_reset __P((void *state));
+static void z_decomp_reset __P((void *state));
+static void z_comp_stats __P((void *state, struct compstat *stats));
+
+struct chunk_header {
+ int valloced; /* allocated with valloc, not kmalloc */
+ int guard; /* check for overwritten header */
+};
+
+#define GUARD_MAGIC 0x77a8011a
+#define MIN_VMALLOC 2048 /* use kmalloc for blocks < this */
+
+/*
+ * Space allocation and freeing routines for use by zlib routines.
+ */
+void zfree(void *arg, void *ptr)
+{
+ struct chunk_header *hdr = ((struct chunk_header *)ptr) - 1;
+
+ if (hdr->guard != GUARD_MAGIC) {
+ printk(KERN_WARNING "zfree: header corrupted (%x %x) at %p\n",
+ hdr->valloced, hdr->guard, hdr);
+ return;
+ }
+ if (hdr->valloced)
+ vfree(hdr);
+ else
+ kfree(hdr);
+}
+
+void *
+zalloc(arg, items, size)
+ void *arg;
+ unsigned int items, size;
+{
+ struct chunk_header *hdr;
+ unsigned nbytes;
+
+ nbytes = items * size + sizeof(*hdr);
+ hdr = kmalloc(nbytes, GFP_ATOMIC);
+ if (hdr == 0)
+ return 0;
+ hdr->valloced = 0;
+ hdr->guard = GUARD_MAGIC;
+ return (void *) (hdr + 1);
+}
+
+void * zalloc_init(void *arg, unsigned int items, unsigned int size)
+{
+ struct chunk_header *hdr;
+ unsigned nbytes;
+
+ nbytes = items * size + sizeof(*hdr);
+ if (nbytes >= MIN_VMALLOC)
+ hdr = vmalloc(nbytes);
+ else
+ hdr = kmalloc(nbytes, GFP_KERNEL);
+ if (hdr == 0)
+ return 0;
+ hdr->valloced = nbytes >= MIN_VMALLOC;
+ hdr->guard = GUARD_MAGIC;
+ return (void *) (hdr + 1);
+}
+
+static void
+z_comp_free(arg)
+ void *arg;
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+
+ if (state) {
+ deflateEnd(&state->strm);
+ kfree(state);
+ MOD_DEC_USE_COUNT;
+ }
+}
+
+/*
+ * Allocate space for a compressor.
+ */
+static void *
+z_comp_alloc(options, opt_len)
+ unsigned char *options;
+ int opt_len;
+{
+ struct irda_deflate_state *state;
+ int w_size;
+
+ if (opt_len != CILEN_DEFLATE
+ || (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT)
+ || options[1] != CILEN_DEFLATE
+ || DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL
+ || options[3] != DEFLATE_CHK_SEQUENCE)
+ return NULL;
+ w_size = DEFLATE_SIZE(options[2]);
+ w_size = MAX_WBITS;
+ if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE)
+ return NULL;
+
+ state = (struct irda_deflate_state *) kmalloc(sizeof(*state), GFP_KERNEL);
+ if (state == NULL)
+ return NULL;
+
+ MOD_INC_USE_COUNT;
+ memset (state, 0, sizeof (struct irda_deflate_state));
+ state->strm.next_in = NULL;
+ state->strm.zalloc = zalloc_init;
+ state->strm.zfree = zfree;
+ state->w_size = w_size;
+
+ if (deflateInit2(&state->strm, Z_DEFAULT_COMPRESSION,
+ DEFLATE_METHOD_VAL, -w_size, 8, Z_DEFAULT_STRATEGY)
+ != Z_OK)
+ goto out_free;
+ state->strm.zalloc = zalloc;
+ return (void *) state;
+
+out_free:
+ z_comp_free(state);
+ MOD_DEC_USE_COUNT;
+ return NULL;
+}
+
+static int
+z_comp_init(arg, options, opt_len, unit, hdrlen, debug)
+ void *arg;
+ unsigned char *options;
+ int opt_len, unit, hdrlen, debug;
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+
+ if (opt_len < CILEN_DEFLATE
+ || (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT)
+ || options[1] != CILEN_DEFLATE
+ || DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL
+ || DEFLATE_SIZE(options[2]) != state->w_size
+ || options[3] != DEFLATE_CHK_SEQUENCE)
+ return 0;
+
+ state->seqno = 0;
+ state->unit = unit;
+ state->debug = debug;
+
+ deflateReset(&state->strm);
+
+ return 1;
+}
+
+static void z_comp_reset(void *arg)
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+
+ state->seqno = 0;
+ deflateReset(&state->strm);
+}
+
+int
+z_compress(arg, rptr, obuf, isize, osize)
+ void *arg;
+ unsigned char *rptr; /* uncompressed packet (in) */
+ unsigned char *obuf; /* compressed packet (out) */
+ int isize, osize;
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+ int r, olen, oavail;
+
+ olen = 0;
+
+ /* Don't generate compressed packets which are larger than
+ the uncompressed packet. */
+ if (osize > isize)
+ osize = isize;
+
+ state->strm.next_out = obuf;
+ state->strm.avail_out = oavail = osize;
+
+ state->strm.next_in = rptr;
+ state->strm.avail_in = isize;
+
+ for (;;) {
+ r = deflate(&state->strm, Z_PACKET_FLUSH);
+ if (r != Z_OK) {
+ if (state->debug)
+ printk(KERN_ERR
+ "z_compress: deflate returned %d\n", r);
+ break;
+ }
+ if (state->strm.avail_out == 0) {
+ olen += oavail;
+ state->strm.next_out = NULL;
+ state->strm.avail_out = oavail = 1000000;
+ } else {
+ break; /* all done */
+ }
+ }
+ olen += oavail - state->strm.avail_out;
+
+ /*
+ * See if we managed to reduce the size of the packet.
+ */
+ if (olen < isize) {
+ state->stats.comp_bytes += olen;
+ state->stats.comp_packets++;
+ } else {
+ state->stats.inc_bytes += isize;
+ state->stats.inc_packets++;
+ olen = 0;
+ }
+ state->stats.unc_bytes += isize;
+ state->stats.unc_packets++;
+
+ return olen;
+}
+
+static void
+z_comp_stats(arg, stats)
+ void *arg;
+ struct compstat *stats;
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+
+ *stats = state->stats;
+}
+
+static void z_decomp_free(void *arg)
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+
+ if (state) {
+ inflateEnd(&state->strm);
+ kfree(state);
+ MOD_DEC_USE_COUNT;
+ }
+}
+
+/*
+ * Allocate space for a decompressor.
+ */
+static void *
+z_decomp_alloc(options, opt_len)
+ unsigned char *options;
+ int opt_len;
+{
+ struct irda_deflate_state *state;
+ int w_size;
+
+ if (opt_len != CILEN_DEFLATE
+ || (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT)
+ || options[1] != CILEN_DEFLATE
+ || DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL
+ || options[3] != DEFLATE_CHK_SEQUENCE)
+ return NULL;
+ w_size = DEFLATE_SIZE(options[2]);
+ w_size = MAX_WBITS;
+ if (w_size < DEFLATE_MIN_SIZE || w_size > DEFLATE_MAX_SIZE)
+ return NULL;
+
+ state = (struct irda_deflate_state *) kmalloc(sizeof(*state), GFP_KERNEL);
+ if (state == NULL)
+ return NULL;
+
+ MOD_INC_USE_COUNT;
+ memset (state, 0, sizeof (struct irda_deflate_state));
+ state->w_size = w_size;
+ state->strm.next_out = NULL;
+ state->strm.zalloc = zalloc_init;
+ state->strm.zfree = zfree;
+
+ if (inflateInit2(&state->strm, -w_size) != Z_OK)
+ goto out_free;
+ state->strm.zalloc = zalloc;
+ return (void *) state;
+
+out_free:
+ z_decomp_free(state);
+ MOD_DEC_USE_COUNT;
+ return NULL;
+}
+
+static int
+z_decomp_init(arg, options, opt_len, unit, hdrlen, mru, debug)
+ void *arg;
+ unsigned char *options;
+ int opt_len, unit, hdrlen, mru, debug;
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+
+ if (opt_len < CILEN_DEFLATE
+ || (options[0] != CI_DEFLATE && options[0] != CI_DEFLATE_DRAFT)
+ || options[1] != CILEN_DEFLATE
+ || DEFLATE_METHOD(options[2]) != DEFLATE_METHOD_VAL
+ || DEFLATE_SIZE(options[2]) != state->w_size
+ || options[3] != DEFLATE_CHK_SEQUENCE)
+ return 0;
+
+ state->seqno = 0;
+ state->unit = unit;
+ state->debug = debug;
+ state->mru = mru;
+
+ inflateReset(&state->strm);
+
+ return 1;
+}
+
+static void z_decomp_reset(void *arg)
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+
+ state->seqno = 0;
+ inflateReset(&state->strm);
+}
+
+/*
+ * Decompress a Deflate-compressed packet.
+ *
+ * Because of patent problems, we return DECOMP_ERROR for errors
+ * found by inspecting the input data and for system problems, but
+ * DECOMP_FATALERROR for any errors which could possibly be said to
+ * be being detected "after" decompression. For DECOMP_ERROR,
+ * we can issue a CCP reset-request; for DECOMP_FATALERROR, we may be
+ * infringing a patent of Motorola's if we do, so we take CCP down
+ * instead.
+ *
+ * Given that the frame has the correct sequence number and a good FCS,
+ * errors such as invalid codes in the input most likely indicate a
+ * bug, so we return DECOMP_FATALERROR for them in order to turn off
+ * compression, even though they are detected by inspecting the input.
+ */
+int
+z_decompress(arg, ibuf, isize, obuf, osize)
+ void *arg;
+ unsigned char *ibuf;
+ int isize;
+ unsigned char *obuf;
+ int osize;
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+ int olen, r;
+ int overflow;
+ unsigned char overflow_buf[1];
+
+ if (isize <= DEFLATE_OVHD) {
+ if (state->debug)
+ printk(KERN_DEBUG "z_decompress%d: short pkt (%d)\n",
+ state->unit, isize);
+ return DECOMP_ERROR;
+ }
+
+ /*
+ * Set up to call inflate.
+ */
+ state->strm.next_in = ibuf;
+ state->strm.avail_in = isize;
+ state->strm.next_out = obuf;
+ state->strm.avail_out = osize;
+ overflow = 0;
+
+ /*
+ * Call inflate, supplying more input or output as needed.
+ */
+ for (;;) {
+ r = inflate(&state->strm, Z_PACKET_FLUSH);
+ if (r != Z_OK) {
+ if (state->debug)
+ printk(KERN_DEBUG "z_decompress%d: inflate returned %d (%s)\n",
+ state->unit, r, (state->strm.msg? state->strm.msg: ""));
+ return DECOMP_FATALERROR;
+ }
+ if (state->strm.avail_out != 0)
+ break; /* all done */
+
+ if (!overflow) {
+ /*
+ * We've filled up the output buffer; the only way to
+ * find out whether inflate has any more characters
+ * left is to give it another byte of output space.
+ */
+ state->strm.next_out = overflow_buf;
+ state->strm.avail_out = 1;
+ overflow = 1;
+ } else {
+ if (state->debug)
+ printk(KERN_DEBUG "z_decompress%d: ran out of mru\n",
+ state->unit);
+ return DECOMP_FATALERROR;
+ }
+ }
+
+ olen = osize + overflow - state->strm.avail_out;
+ state->stats.unc_bytes += olen;
+ state->stats.unc_packets++;
+ state->stats.comp_bytes += isize;
+ state->stats.comp_packets++;
+
+ return olen;
+}
+
+/*
+ * Incompressible data has arrived - add it to the history.
+ */
+static void
+z_incomp(arg, ibuf, icnt)
+ void *arg;
+ unsigned char *ibuf;
+ int icnt;
+{
+ struct irda_deflate_state *state = (struct irda_deflate_state *) arg;
+ int r;
+
+ /*
+ * Check that the protocol is one we handle.
+ */
+
+ /*
+ * We start at the either the 1st or 2nd byte of the protocol field,
+ * depending on whether the protocol value is compressible.
+ */
+ state->strm.next_in = ibuf;
+ state->strm.avail_in = icnt;
+
+ r = inflateIncomp(&state->strm);
+ if (r != Z_OK) {
+ /* gak! */
+ if (state->debug) {
+ printk(KERN_DEBUG "z_incomp%d: inflateIncomp returned %d (%s)\n",
+ state->unit, r, (state->strm.msg? state->strm.msg: ""));
+ }
+ return;
+ }
+
+ /*
+ * Update stats.
+ */
+ state->stats.inc_bytes += icnt;
+ state->stats.inc_packets++;
+ state->stats.unc_bytes += icnt;
+ state->stats.unc_packets++;
+}
+
+/*************************************************************
+ * Module interface table
+ *************************************************************/
+
+/* These are in ppp.c */
+extern int irda_register_compressor (struct compressor *cp);
+extern void irda_unregister_compressor (struct compressor *cp);
+
+/*
+ * Procedures exported to if_ppp.c.
+ */
+static struct compressor irda_deflate = {
+ CI_DEFLATE, /* compress_proto */
+ z_comp_alloc, /* comp_alloc */
+ z_comp_free, /* comp_free */
+ z_comp_init, /* comp_init */
+ z_comp_reset, /* comp_reset */
+ z_compress, /* compress */
+ z_comp_stats, /* comp_stat */
+ z_decomp_alloc, /* decomp_alloc */
+ z_decomp_free, /* decomp_free */
+ z_decomp_init, /* decomp_init */
+ z_decomp_reset, /* decomp_reset */
+ z_decompress, /* decompress */
+ z_incomp, /* incomp */
+ z_comp_stats, /* decomp_stat */
+};
+
+static struct compressor irda_deflate_draft = {
+ CI_DEFLATE_DRAFT, /* compress_proto */
+ z_comp_alloc, /* comp_alloc */
+ z_comp_free, /* comp_free */
+ z_comp_init, /* comp_init */
+ z_comp_reset, /* comp_reset */
+ z_compress, /* compress */
+ z_comp_stats, /* comp_stat */
+ z_decomp_alloc, /* decomp_alloc */
+ z_decomp_free, /* decomp_free */
+ z_decomp_init, /* decomp_init */
+ z_decomp_reset, /* decomp_reset */
+ z_decompress, /* decompress */
+ z_incomp, /* incomp */
+ z_comp_stats, /* decomp_stat */
+};
+
+__initfunc(int irda_deflate_init(void))
+{
+ int answer = irda_register_compressor ( &irda_deflate);
+ if (answer == 0)
+ printk (KERN_INFO
+ "IrDA Deflate Compression module registered\n");
+ irda_register_compressor( &irda_deflate_draft);
+ return answer;
+}
+
+void irda_deflate_cleanup(void)
+{
+
+ irda_unregister_compressor (&irda_deflate);
+ irda_unregister_compressor (&irda_deflate_draft);
+}
+
+#ifdef MODULE
+/*************************************************************
+ * Module support routines
+ *************************************************************/
+
+int init_module(void)
+{
+ return irda_deflate_init();
+}
+
+void
+cleanup_module(void)
+{
+ if (MOD_IN_USE)
+ printk (KERN_INFO
+ "Deflate Compression module busy, remove delayed\n");
+ else {
+ irda_deflate_cleanup();
+ }
+}
+#endif
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