summaryrefslogtreecommitdiffstats
path: root/src/libs/xpcom18a4/xpcom/io/nsIStreamBufferAccess.idl
diff options
context:
space:
mode:
Diffstat (limited to 'src/libs/xpcom18a4/xpcom/io/nsIStreamBufferAccess.idl')
-rw-r--r--src/libs/xpcom18a4/xpcom/io/nsIStreamBufferAccess.idl191
1 files changed, 191 insertions, 0 deletions
diff --git a/src/libs/xpcom18a4/xpcom/io/nsIStreamBufferAccess.idl b/src/libs/xpcom18a4/xpcom/io/nsIStreamBufferAccess.idl
new file mode 100644
index 00000000..dc41585f
--- /dev/null
+++ b/src/libs/xpcom18a4/xpcom/io/nsIStreamBufferAccess.idl
@@ -0,0 +1,191 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla FastLoad code.
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 2001
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ * Brendan Eich <brendan@mozilla.org> (original author)
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "nsISupports.idl"
+#include "nsrootidl.idl"
+
+/**
+ * An interface for access to a buffering stream implementation's underlying
+ * memory buffer.
+ *
+ * Stream implementations that QueryInterface to nsIStreamBufferAccess must
+ * ensure that all buffers are aligned on the most restrictive type size for
+ * the current architecture (e.g., sizeof(double) for RISCy CPUs). malloc(3)
+ * satisfies this requirement.
+ */
+[uuid(ac923b72-ac87-4892-ac7a-ca385d429435)]
+interface nsIStreamBufferAccess : nsISupports
+{
+ /**
+ * Get access to a contiguous, aligned run of bytes in the stream's buffer.
+ * Exactly one successful getBuffer call must occur before a putBuffer call
+ * taking the non-null pointer returned by the successful getBuffer.
+ *
+ * The run of bytes are the next bytes (modulo alignment padding) to read
+ * for an input stream, and the next bytes (modulo alignment padding) to
+ * store before (eventually) writing buffered data to an output stream.
+ * There can be space beyond this run of bytes in the buffer for further
+ * accesses before the fill or flush point is reached.
+ *
+ * @param aLength
+ * Count of contiguous bytes requested at the address A that satisfies
+ * (A & aAlignMask) == 0 in the buffer, starting from the current stream
+ * position, mapped to a buffer address B. The stream implementation
+ * must pad from B to A by skipping bytes (if input stream) or storing
+ * zero bytes (if output stream).
+ *
+ * @param aAlignMask
+ * Bit-mask computed by subtracting 1 from the power-of-two alignment
+ * modulus (e.g., 3 or sizeof(PRUint32)-1 for PRUint32 alignment).
+ *
+ * @return
+ * The aligned pointer to aLength bytes in the buffer, or null if the
+ * buffer has no room for aLength bytes starting at the next address A
+ * after the current position that satisfies (A & aAlignMask) == 0.
+ */
+ [notxpcom] charPtr getBuffer(in PRUint32 aLength, in PRUint32 aAlignMask);
+
+ /**
+ * Relinquish access to the stream's buffer, filling if at end of an input
+ * buffer, flushing if completing an output buffer. After a getBuffer call
+ * that returns non-null, putBuffer must be called.
+ *
+ * @param aBuffer
+ * A non-null pointer returned by getBuffer on the same stream buffer
+ * access object.
+ *
+ * @param aLength
+ * The same count of contiguous bytes passed to the getBuffer call that
+ * returned aBuffer.
+ */
+ [notxpcom] void putBuffer(in charPtr aBuffer, in PRUint32 aLength);
+
+ /**
+ * Disable and enable buffering on the stream implementing this interface.
+ * DisableBuffering flushes an output stream's buffer, and invalidates an
+ * input stream's buffer.
+ */
+ void disableBuffering();
+ void enableBuffering();
+
+ /**
+ * The underlying, unbuffered input or output stream.
+ */
+ readonly attribute nsISupports unbufferedStream;
+};
+
+%{C++
+
+// Swap macros, used to convert to/from canonical (big-endian) format
+#if defined IS_LITTLE_ENDIAN
+
+# define NS_SWAP16(x) ((((x) & 0xff) << 8) | (((x) >> 8) & 0xff))
+# define NS_SWAP32(x) ((NS_SWAP16((x) & 0xffff) << 16) | (NS_SWAP16((x) >> 16)))
+
+// We want to avoid casting to 32-bit types if possible, since that violates
+// aliasing rules (a standard compiler may assume that pointers of two types
+// do not address overlapping storage).
+//
+// XXX What if we have a compiler that follows aliasing rules strictly but
+// doesn't have a 64-bit int type?
+//
+// XXXbe shouldn't NSPR's LL_INIT work for non-constant arguments in all cases?
+
+# if defined HAVE_LONG_LONG
+# if PR_BYTES_PER_LONG == 8
+# define ULL_(x) x ## UL
+# elif (defined WIN32 || defined WIN16) && !defined __GNUC__
+# define ULL_(x) ((uint64) x ## i64)
+# else
+# define ULL_(x) x ## ULL
+# endif
+
+# define NS_SWAP64(x) ((((x) & ULL_(0xff00000000000000)) >> 56) | \
+ (((x) & ULL_(0x00ff000000000000)) >> 40) | \
+ (((x) & ULL_(0x0000ff0000000000)) >> 24) | \
+ (((x) & ULL_(0x000000ff00000000)) >> 8) | \
+ (((x) & ULL_(0x00000000ff000000)) << 8) | \
+ (((x) & ULL_(0x0000000000ff0000)) << 24) | \
+ (((x) & ULL_(0x000000000000ff00)) << 40) | \
+ (((x) /* & ULL_(0x00000000000000ff) */) << 56))
+# else
+# define NS_SWAP64(x) LL_INIT((((x).lo /* & 0xff000000ul */) >> 24) | \
+ (((x).lo & 0x00ff0000ul) >> 8) | \
+ (((x).lo & 0x0000ff00ul) << 8) | \
+ (((x).lo /* & 0x000000fful */) << 24), \
+ (((x).hi /* & 0xff000000ul */) >> 24) | \
+ (((x).hi & 0x00ff0000ul) >> 8) | \
+ (((x).hi & 0x0000ff00ul) << 8) | \
+ (((x).hi /* & 0x000000fful */) << 24))
+# endif
+
+#elif defined IS_BIG_ENDIAN
+
+# define NS_SWAP16(x) (x)
+# define NS_SWAP32(x) (x)
+# define NS_SWAP64(x) (x)
+
+#else
+
+# error "Unknown byte order"
+
+#endif
+
+/**
+ * These macros get and put a buffer given either an sba parameter that may
+ * point to an object implementing nsIStreamBufferAccess, nsIObjectInputStream,
+ * or nsIObjectOutputStream.
+ */
+#define NS_GET_BUFFER(sba,n,a) ((sba)->GetBuffer(n, a))
+#define NS_PUT_BUFFER(sba,p,n) ((sba)->PutBuffer(p, n))
+
+#define NS_GET8(p) (*(PRUint8*)(p))
+#define NS_GET16(p) NS_SWAP16(*(PRUint16*)(p))
+#define NS_GET32(p) NS_SWAP32(*(PRUint32*)(p))
+#define NS_GET64(p) NS_SWAP64(*(PRUint64*)(p))
+#define NS_GET_FLOAT(p) ((float)NS_SWAP32(*(PRUint32*)(p)))
+#define NS_GET_DOUBLE(p) ((double)NS_SWAP64(*(PRUint64*)(p)))
+
+#define NS_PUT8(p,x) (*(PRUint8*)(p) = (x))
+#define NS_PUT16(p,x) (*(PRUint16*)(p) = NS_SWAP16(x))
+#define NS_PUT32(p,x) (*(PRUint32*)(p) = NS_SWAP32(x))
+#define NS_PUT64(p,x) (*(PRUint64*)(p) = NS_SWAP64(x))
+#define NS_PUT_FLOAT(p,x) (*(PRUint32*)(p) = NS_SWAP32(*(PRUint32*)&(x)))
+#define NS_PUT_DOUBLE(p,x) (*(PRUint64*)(p) = NS_SWAP64(*(PRUint64*)&(x)))
+
+%}