[Gnash-commit] gnash ChangeLog server/stream.cpp server/stream...

[Sandro Santilli]

CVSROOT:        /sources/gnash
Module name:    gnash
Changes by:     Sandro Santilli <strk>  07/08/27 12:09:06

Modified files:
        .              : ChangeLog 
        server         : stream.cpp stream.h 
        server/parser  : shape_character_def.cpp 
        testsuite/server: StreamTest.cpp 

Log message:
                * server/stream.{cpp,h}: add read_bit(), optimize read_uint()
                  a little-bit (there are likely more optimization options).
                * server/parser/shape_character_def.cpp (read): use read_bit()
                  instead of read_uint(1).
                * testsuite/server/StreamTest.cpp: more tests for read_bit().

CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/gnash/ChangeLog?cvsroot=gnash&r1=1.4114&r2=1.4115
http://cvs.savannah.gnu.org/viewcvs/gnash/server/stream.cpp?cvsroot=gnash&r1=1.26&r2=1.27
http://cvs.savannah.gnu.org/viewcvs/gnash/server/stream.h?cvsroot=gnash&r1=1.25&r2=1.26
http://cvs.savannah.gnu.org/viewcvs/gnash/server/parser/shape_character_def.cpp?cvsroot=gnash&r1=1.33&r2=1.34
http://cvs.savannah.gnu.org/viewcvs/gnash/testsuite/server/StreamTest.cpp?cvsroot=gnash&r1=1.2&r2=1.3

Patches:
Index: ChangeLog
===================================================================
RCS file: /sources/gnash/gnash/ChangeLog,v
retrieving revision 1.4114
retrieving revision 1.4115
diff -u -b -r1.4114 -r1.4115
--- ChangeLog   27 Aug 2007 11:58:46 -0000      1.4114
+++ ChangeLog   27 Aug 2007 12:09:04 -0000      1.4115
@@ -1,3 +1,11 @@
+2007-08-27 Sandro Santilli <address@hidden>
+
+       * server/stream.{cpp,h}: add read_bit(), optimize read_uint()
+         a little-bit (there are likely more optimization options).
+       * server/parser/shape_character_def.cpp (read): use read_bit()
+         instead of read_uint(1).
+       * testsuite/server/StreamTest.cpp: more tests for read_bit().
+
 2007-08-27 Markus Gothe <address@hidden>
 
        * libbase/utility.h: defined exp2() as it's missing on some BSDen.

Index: server/stream.cpp
===================================================================
RCS file: /sources/gnash/gnash/server/stream.cpp,v
retrieving revision 1.26
retrieving revision 1.27
diff -u -b -r1.26 -r1.27
--- server/stream.cpp   27 Aug 2007 03:06:41 -0000      1.26
+++ server/stream.cpp   27 Aug 2007 12:09:05 -0000      1.27
@@ -54,44 +54,71 @@
 //     }
 
        
+       bool stream::read_bit()
+       {
+               if (!m_unused_bits)
+               {
+                       m_current_byte = m_input->read_byte();
+                       m_unused_bits = 7;
+                       return (m_current_byte&0x80);
+               }
+               else
+               {
+                       return ( m_current_byte & (1<<(--m_unused_bits)) );
+               }
+       }
+
        unsigned stream::read_uint(unsigned short bitcount)
        {
-               assert(bitcount <= 32);
+               assert(bitcount <= 24);
+
+               if (!m_unused_bits)
+               {
+                       m_current_byte = m_input->read_byte();
+                       m_unused_bits = 8;
+               }
                        
                uint32_t        value = 0;
 
                unsigned short bits_needed = bitcount;
-               while (bits_needed > 0)
+               do
+               {
+                       // TODO: cache this mask instead of m_unused_bits ?
+                       int unusedMask = (1 << m_unused_bits)-1;
+
+                       if (bits_needed == m_unused_bits)
                {
-                       if (m_unused_bits) {
-                               if (bits_needed >= m_unused_bits) {
                                        // Consume all the unused bits.
-                                       value |= (m_current_byte << 
(bits_needed - m_unused_bits));
+                               value |= (m_current_byte&unusedMask);
+                               m_unused_bits = 0;
+                               break;
 
-                                       bits_needed -= m_unused_bits;
+                       }
+                       else if (bits_needed > m_unused_bits)
+                       {
+                               // Consume all the unused bits.
 
-                                       m_current_byte = 0;
-                                       m_unused_bits = 0;
+                               bits_needed -= m_unused_bits; // 
assert(bits_needed>0)
 
-                               } else {
-                                       // Consume some of the unused bits.
-                                       value |= (m_current_byte >> 
(m_unused_bits - bits_needed));
+                               value |= ((m_current_byte&unusedMask) << 
bits_needed);
 
-                                       // mask off the bits we consumed.
-                                       m_current_byte &= ((1 << (m_unused_bits 
- bits_needed)) - 1);
+                               m_current_byte = m_input->read_byte();
+                               m_unused_bits = 8;
+
+                       }
+                       else
+                       {
+                               // Consume some of the unused bits.
 
                                        m_unused_bits -= bits_needed;
 
+                               value |= ((m_current_byte&unusedMask) >> 
m_unused_bits);
+
                                        // We're done.
-                                       bits_needed = 0;
+                               break;
                                }
-                       } else {
-                               m_current_byte = m_input->read_byte();
-                               m_unused_bits = 8;
                        }
-               }
-
-               assert(bits_needed == 0);
+               while (bits_needed > 0);
 
                return value;
        }

Index: server/stream.h
===================================================================
RCS file: /sources/gnash/gnash/server/stream.h,v
retrieving revision 1.25
retrieving revision 1.26
diff -u -b -r1.25 -r1.26
--- server/stream.h     26 Aug 2007 15:14:12 -0000      1.25
+++ server/stream.h     27 Aug 2007 12:09:05 -0000      1.26
@@ -46,6 +46,11 @@
                unsigned read_uint(unsigned short bitcount);
 
                /// \brief
+               /// Reads a single bit off the stream
+               /// and returns it.  
+               bool read_bit();
+
+               /// \brief
                /// Reads a bit-packed little-endian signed integer
                /// from the stream.  The given bitcount determines the
                /// number of bits to read.

Index: server/parser/shape_character_def.cpp
===================================================================
RCS file: /sources/gnash/gnash/server/parser/shape_character_def.cpp,v
retrieving revision 1.33
retrieving revision 1.34
diff -u -b -r1.33 -r1.34
--- server/parser/shape_character_def.cpp       23 Aug 2007 15:10:51 -0000      
1.33
+++ server/parser/shape_character_def.cpp       27 Aug 2007 12:09:05 -0000      
1.34
@@ -17,7 +17,7 @@
 // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 //
 
-/* $Id: shape_character_def.cpp,v 1.33 2007/08/23 15:10:51 strk Exp $ */
+/* $Id: shape_character_def.cpp,v 1.34 2007/08/27 12:09:05 strk Exp $ */
 
 // Based on the public domain shape.cpp of Thatcher Ulrich <address@hidden> 
2003
 
@@ -226,8 +226,8 @@
 
     // SHAPERECORDS
     for (;;) {
-       int     type_flag = in->read_uint(1);
-       if (type_flag == 0) {
+       bool isEdgeRecord = in->read_bit();
+       if (!isEdgeRecord) {
            // Parse the record.
            int flags = in->read_uint(5);
            if (flags == flagEnd) {
@@ -430,7 +430,7 @@
            }
        } else {
            // EDGERECORD
-           int edge_flag = in->read_uint(1);
+           bool edge_flag = in->read_bit();
            if (edge_flag == 0) {
                // curved edge
                int num_bits = 2 + in->read_uint(4);
@@ -453,14 +453,14 @@
            } else {
                // straight edge
                int     num_bits = 2 + in->read_uint(4);
-               int     line_flag = in->read_uint(1);
+               bool line_flag = in->read_bit();
                float   dx = 0, dy = 0;
                if (line_flag) {
                    // General line.
                    dx = (float) in->read_sint(num_bits);
                    dy = (float) in->read_sint(num_bits);
                } else {
-                   int vert_flag = in->read_uint(1);
+                   bool vert_flag = in->read_bit();
                    if (vert_flag == 0) {
                        // Horizontal line.
                        dx = (float) in->read_sint(num_bits);

Index: testsuite/server/StreamTest.cpp
===================================================================
RCS file: /sources/gnash/gnash/testsuite/server/StreamTest.cpp,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -b -r1.2 -r1.3
--- testsuite/server/StreamTest.cpp     27 Aug 2007 08:28:42 -0000      1.2
+++ testsuite/server/StreamTest.cpp     27 Aug 2007 12:09:05 -0000      1.3
@@ -57,6 +57,11 @@
                b(by)
        {}
 
+       void setByte(unsigned char by)
+       {
+               b=by;
+       }
+
        static int readFunc(void* dst, int bytes, void* appdata) 
        {
            assert(bytes == 1);
@@ -97,10 +102,6 @@
        ret = s.read_uint(1); check_equals(ret, 0);
        ret = s.read_uint(1); check_equals(ret, 1);
        ret = s.read_uint(1); check_equals(ret, 0);
-
-       /// bits: 10101010 (0xAA)
-
-       s.align();
        ret = s.read_uint(1); check_equals(ret, 1);
        ret = s.read_uint(1); check_equals(ret, 0);
        ret = s.read_uint(1); check_equals(ret, 1);
@@ -213,6 +214,39 @@
        s.align();
        ret = s.read_uint(24); check_equals(ret, 11184810);
 
+       /// bits: 1010101010101010 (0xAAAA)
+
+       s.align();
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+
+       /// bits: 10011001 (0x99)
+
+       br.setByte(0x99);
+       s.align();
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 1);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 0);
+       ret = s.read_bit(); check_equals(ret, 1);
+
        return 0;
 }