1998-09-06 OKUJI Yoshinori <okuji@kuicr.kyoto-u.ac.jp>

	* bunzip2.c: New file.
	* store.h (store_bunzip2_create): New declarations.
	(store_bunzip2_open): Likewise.
	(store_bunzip2_class): Likewise.
	* std.c (store_std_classes): Add store_bunzip2_class.
	* Makefile (SRCS): Add bunzip2.c.
	(UNZIP_OBJS): Add do-bunzip2.o.

5 files changed, 288 insertions, 3 deletions

diff --git a/libstore/ChangeLog b/libstore/ChangeLog
index 576482e4..a5674cbc 100644
--- a/libstore/ChangeLog
+++ b/libstore/ChangeLog
@@ -1,3 +1,13 @@
+1998-09-06  OKUJI Yoshinori  <okuji@kuicr.kyoto-u.ac.jp>
+
+	* bunzip2.c: New file.
+	* store.h (store_bunzip2_create): New declarations.
+	(store_bunzip2_open): Likewise.
+	(store_bunzip2_class): Likewise.
+	* std.c (store_std_classes): Add store_bunzip2_class.
+	* Makefile (SRCS): Add bunzip2.c.
+	(UNZIP_OBJS): Add do-bunzip2.o.
+	
 1998-12-27  Roland McGrath  <roland@baalperazim.frob.com>
 
 	* store.h: Remove defns of STORAGE_*, now in <hurd/hurd_types.h>.
diff --git a/libstore/Makefile b/libstore/Makefile
index edf47996..35f74fdc 100644
--- a/libstore/Makefile
+++ b/libstore/Makefile
@@ -25,11 +25,12 @@ makemode := library
 libname = libstore
 SRCS = create.c derive.c make.c rdwr.c set.c device.c file.c stripe.c	   \
 	enc.c encode.c decode.c clone.c argp.c std.c kids.c zero.c flags.c \
-	open.c remap.c xinl.c task.c typed.c copy.c gunzip.c map.c mvol.c
+	open.c remap.c xinl.c task.c typed.c copy.c gunzip.c map.c mvol.c \
+	bunzip2.c
 LCLHDRS=store.h
 installhdrs=store.h
 
-UNZIP_OBJS = unzip.o inflate.o util.o
+UNZIP_OBJS = unzip.o inflate.o util.o do-bunzip2.o
 OBJS = $(SRCS:.c=.o) $(UNZIP_OBJS)
 
 # Look for zip stuff
diff --git a/libstore/bunzip2.c b/libstore/bunzip2.c
new file mode 100644
index 00000000..e2858322
--- /dev/null
+++ b/libstore/bunzip2.c
@@ -0,0 +1,259 @@
+/* Decompressing store backend
+
+   Copyright (C) 1998 Free Software Foundation, Inc.
+   Written by okuji@kuicr.kyoto-u.ac.jp <okuji@kuicr.kyoto-u.ac.jp>
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   The GNU Hurd 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., 59 Temple Place - Suite 330, Boston, MA 02111, USA. */
+
+#include <stdio.h>
+#include <string.h>
+#include <setjmp.h>
+#include <cthreads.h>
+
+#include "store.h"
+
+
+#define IN_BUFFERING  (256*1024)
+#define OUT_BUFFERING (512*1024)
+
+static struct mutex bunzip2_lock = MUTEX_INITIALIZER;
+
+/* Uncompress the contents of FROM, which should contain a valid bzip2 file,
+   into memory, returning the result buffer in BUF & BUF_LEN.  */
+static error_t
+bunzip2 (struct store *from, void **buf, size_t *buf_len)
+{
+  /* Callbacks from bunzip2 for I/O and error interface.  */
+  extern int (*unzip_read) (char *buf, size_t maxread);
+  extern void (*unzip_write) (const char *buf, size_t nwrite);
+  extern void (*unzip_read_error) (void);
+  extern void (*unzip_error) (const char *msg);
+
+  /* How we return errors from our hook functions.  */
+  jmp_buf zerr_jmp_buf;
+  error_t zerr;
+
+  /* vm_alloced buffer for the input store.  */
+  void *in_buf = 0;
+  size_t in_buf_len = 0;
+  size_t in_buf_offs = 0;	/* Offset of read point in IN_BUF.  */
+  off_t in_buf_addr = 0;	/* Address in FROM of *next* IN_BUF.  */
+
+  /* Buffer input in units that are least IN_BUFFERING bytes, but are also a
+     multiple of FROM's block size.  */
+  size_t in_addr_mask = ((1 << from->log2_block_size) - 1);
+  size_t in_buffering = ((IN_BUFFERING + in_addr_mask) & ~in_addr_mask);
+
+  /* Read at most MAXREAD (or 0 if eof) bytes into BUF from our current
+     position in FROM.  */
+  int zread (char *buf, size_t maxread)
+    {
+      size_t did_read = 0;
+
+      while (maxread > 0)
+	{
+	  size_t left = in_buf_len - in_buf_offs;
+
+	  if (left > 0)
+	    /* Fill BUF with what we can from IN_BUF.  */
+	    {
+	      if (left > maxread)
+		left = maxread;
+	      bcopy (in_buf + in_buf_offs, buf, left);
+	      in_buf_offs += left;
+	      buf += left;
+	      maxread -= left;
+	      did_read += left;
+	    }
+
+	  /* Limit MAXREAD to the number of bytes left in the input.  */
+	  if (maxread > (from->size - (in_buf_addr << from->log2_block_size)))
+	    maxread = from->size - (in_buf_addr << from->log2_block_size);
+
+	  if (maxread > 0)
+	    /* Have to fill IN_BUF again.  */
+	    {
+	      void *new_in_buf = in_buf;
+	      size_t new_in_buf_len = in_buf_len;
+
+	      zerr = store_read (from, in_buf_addr, in_buffering,
+				 &new_in_buf, &new_in_buf_len);
+	      if (zerr)
+		longjmp (zerr_jmp_buf, 1);
+
+	      in_buf_addr += (new_in_buf_len >> from->log2_block_size);
+
+	      if (new_in_buf != in_buf)
+		{
+		  if (in_buf_len > 0)
+		    vm_deallocate (mach_task_self (),
+				   (vm_address_t)in_buf, in_buf_len);
+		  in_buf = new_in_buf;
+		  in_buf_len = new_in_buf_len;
+		}
+
+	      in_buf_offs = 0;
+	    }
+	}
+      return did_read;
+    }
+
+  size_t out_buf_offs = 0;	/* Position in the output buffer.  */
+
+  /* Write compress data to our output buffer.  */
+  void zwrite (const char *wbuf, size_t nwrite)
+    {
+      size_t old_buf_len = *buf_len;
+
+      if (out_buf_offs + nwrite > old_buf_len)
+	/* Have to grow the output buffer.  */
+	{
+	  void *old_buf = *buf;
+	  void *new_buf = old_buf + old_buf_len; /* First try.  */
+	  size_t new_buf_len = round_page (old_buf_len + old_buf_len + nwrite);
+
+	  /* Try to grow the buffer.  */
+	  zerr =
+	    vm_allocate (mach_task_self (),
+			 (vm_address_t *)&new_buf, new_buf_len - old_buf_len,
+			 0);
+	  if (zerr)
+	    /* Can't do that, try to make a bigger buffer elsewhere.  */
+	    {
+	      new_buf = old_buf;
+	      zerr =
+		vm_allocate (mach_task_self (),
+			     (vm_address_t *)&new_buf, new_buf_len, 1);
+	      if (zerr)
+		longjmp (zerr_jmp_buf, 1);
+
+	      if (out_buf_offs > 0)
+		/* Copy the old buffer into the start of the new & free it. */
+		bcopy (old_buf, new_buf, out_buf_offs);
+
+	      vm_deallocate (mach_task_self (),
+			     (vm_address_t)old_buf, old_buf_len);
+
+	      *buf = new_buf;
+	    }
+
+	  *buf_len = new_buf_len;
+	}
+
+      bcopy (wbuf, *buf + out_buf_offs, nwrite);
+      out_buf_offs += nwrite;
+    }
+
+  void zreaderr (void)
+    {
+      zerr = EIO;
+      longjmp (zerr_jmp_buf, 1);
+    }
+  void zerror (const char *msg)
+    {
+      zerr = EINVAL;
+      longjmp (zerr_jmp_buf, 2);
+    }
+
+  /* Try to guess a reasonable output buffer size.  */
+  *buf_len = round_page (from->size * 2);
+  zerr = vm_allocate (mach_task_self (), (vm_address_t *)buf, *buf_len, 1);
+  if (zerr)
+    return zerr;
+
+  mutex_lock (&bunzip2_lock);
+
+  unzip_read = zread;
+  unzip_write = zwrite;
+  unzip_read_error = zreaderr;
+  unzip_error = zerror;
+
+  if (! setjmp (zerr_jmp_buf))
+    {
+      /* Call the bunzip2 engine.  */
+      do_bunzip2 ();
+      zerr = 0;
+    }
+
+  mutex_unlock (&bunzip2_lock);
+
+  if (in_buf_len > 0)
+    vm_deallocate (mach_task_self (), (vm_address_t)in_buf, in_buf_len);
+
+  if (zerr)
+    {
+      if (*buf_len > 0)
+	vm_deallocate (mach_task_self (), (vm_address_t)*buf, *buf_len);
+    }
+  else if (out_buf_offs < *buf_len)
+    /* Trim the output buffer to be the right length.  */
+    {
+      size_t end = round_page (out_buf_offs);
+      if (end < *buf_len)
+	vm_deallocate (mach_task_self (),
+		       (vm_address_t)(*buf + end), *buf_len - end);
+      *buf_len = out_buf_offs;
+    }
+
+  return zerr;
+}
+
+/* Return a new store in STORE which contains a snapshot of the uncompressed
+   contents of the store FROM; FROM is consumed.  */
+error_t
+store_bunzip2_create (struct store *from, int flags, struct store **store)
+{
+  void *buf;
+  size_t buf_len;
+  error_t err = bunzip2 (from, &buf, &buf_len);
+
+  if (! err)
+    {
+      err = store_buffer_create (buf, buf_len, flags, store);
+      if (err)
+	vm_deallocate (mach_task_self (), (vm_address_t)buf, buf_len);
+      else
+	store_free (from);
+    }
+
+  return err;
+}
+
+/* Open the bunzip2 NAME -- which consists of another store-class name, a ':',
+   and a name for that store class to open -- and return the corresponding
+   store in STORE.  CLASSES is used to select classes specified by the type
+   name; if it is 0, STORE_STD_CLASSES is used.  */
+error_t
+store_bunzip2_open (const char *name, int flags,
+		    const struct store_class *const *classes,
+		    struct store **store)
+{
+  struct store *from;
+  error_t err =
+    store_typed_open (name, flags | STORE_HARD_READONLY, classes, &from);
+
+  if (! err)
+    {
+      err = store_bunzip2_create (from, flags, store);
+      if (err)
+	store_free (from);
+    }
+
+  return err;
+}
+
+struct store_class
+store_bunzip2_class = { -1, "bunzip2", open: store_bunzip2_open };
diff --git a/libstore/std.c b/libstore/std.c
index 466fa261..e42e2094 100644
--- a/libstore/std.c
+++ b/libstore/std.c
@@ -26,7 +26,7 @@ store_std_classes[] =
   &store_device_class, &store_file_class, &store_zero_class, &store_task_class,
   &store_ileave_class, &store_concat_class, &store_remap_class,
   &store_query_class, &store_copy_class, &store_gunzip_class,
-  &store_typed_open_class,
+  &store_bunzip2_class, &store_typed_open_class,
   0
 };
 
diff --git a/libstore/store.h b/libstore/store.h
index 88f5d635..f0b20b9e 100644
--- a/libstore/store.h
+++ b/libstore/store.h
@@ -444,6 +444,20 @@ error_t store_gunzip_open (const char *name, int flags,
 			   const struct store_class *const *classes,
 			   struct store **store);
 
+/* Return a new store in STORE which contains a snapshot of the uncompressed
+   contents of the store FROM; FROM is consumed.  BLOCK_SIZE is the desired
+   block size of the result.  */
+error_t store_bunzip2_create (struct store *from, int flags,
+			      struct store **store);
+
+/* Open the bunzip2 NAME -- which consists of another store-class name, a ':',
+   and a name for that store class to open -- and return the corresponding
+   store in STORE.  CLASSES is used to select classes specified by the type
+   name; if it is 0, STORE_STD_CLASSES is used.  */
+error_t store_bunzip2_open (const char *name, int flags,
+			    const struct store_class *const *classes,
+			    struct store **store);
+
 /* Return a new store in STORE that multiplexes multiple physical volumes
    from PHYS as one larger virtual volume.  SWAP_VOLS is a function that will
    be called whenever the volume currently active isn't correct.  PHYS is
@@ -467,6 +481,7 @@ extern const struct store_class store_remap_class;
 extern const struct store_class store_query_class;
 extern const struct store_class store_copy_class;
 extern const struct store_class store_gunzip_class;
+extern const struct store_class store_bunzip2_class;
 extern const struct store_class store_typed_open_class;
 
 /* The following are not included in STORE_STD_CLASSES.  */