Load pcre-6.5 into code/trunk.

git-svn-id: svn://vcs.exim.org/pcre/code/trunk@87 2f5784b3-3f2a-0410-8824-cb99058d5e15

1 files changed, 56 insertions, 60 deletions

diff --git a/ucpinternal.h b/ucpinternal.h
index faefb03..16dfbe9 100644
--- a/ucpinternal.h
+++ b/ucpinternal.h
@@ -1,91 +1,87 @@
 /*************************************************
-*     libucp - Unicode Property Table handler    *
+*           Unicode Property Table handler       *
 *************************************************/
 
-/* Internal header file defining the layout of compact nodes in the tree. */
+/* Internal header file defining the layout of the bits in each pair of 32-bit
+words that form a data item in the table. */
 
 typedef struct cnode {
-  unsigned short int f0;
-  unsigned short int f1;
-  unsigned short int f2;
+  pcre_uint32 f0;
+  pcre_uint32 f1;
 } cnode;
 
 /* Things for the f0 field */
 
-#define f0_leftexists   0x8000    /* Left child exists */
-#define f0_typemask     0x3f00    /* Type bits */
-#define f0_typeshift         8    /* Type shift */
-#define f0_chhmask      0x00ff    /* Character high bits */
+#define f0_scriptmask   0xff000000  /* Mask for script field */
+#define f0_scriptshift          24  /* Shift for script value */
+#define f0_rangeflag    0x00f00000  /* Flag for a range item */
+#define f0_charmask     0x001fffff  /* Mask for code point value */
 
-/* Things for the f2 field */
+/* Things for the f1 field */
 
-#define f2_rightmask    0xf000    /* Mask for right offset bits */
-#define f2_rightshift       12    /* Shift for right offset */
-#define f2_casemask     0x0fff    /* Mask for case offset */
+#define f1_typemask     0xfc000000  /* Mask for char type field */
+#define f1_typeshift            26  /* Shift for the type field */
+#define f1_rangemask    0x0000ffff  /* Mask for a range offset */
+#define f1_casemask     0x0000ffff  /* Mask for a case offset */
+#define f1_caseneg      0xffff8000  /* Bits for negation */
 
-/* The tree consists of a vector of structures of type cnode, with the root
-node as the first element. The three short ints (16-bits) are used as follows:
+/* The data consists of a vector of structures of type cnode. The two unsigned
+32-bit integers are used as follows:
 
-(f0) (1) The 0x8000 bit of f0 is set if a left child exists. The child's node
-         is the next node in the vector.
-     (2) The 0x4000 bits of f0 is spare.
-     (3) The 0x3f00 bits of f0 contain the character type; this is a number
-         defined by the enumeration in ucp.h (e.g. ucp_Lu).
-     (4) The bottom 8 bits of f0 contain the most significant byte of the
-         character's 24-bit codepoint.
+(f0) (1) The most significant byte holds the script number. The numbers are
+         defined by the enum in ucp.h.
 
-(f1) (1) The f1 field contains the two least significant bytes of the
-         codepoint.
+     (2) The 0x00800000 bit is set if this entry defines a range of characters.
+         It is not set if this entry defines a single character
 
-(f2) (1) The 0xf000 bits of f2 contain zero if there is no right child of this
-         node. Otherwise, they contain one plus the exponent of the power of
-         two of the offset to the right node (e.g. a value of 3 means 8). The
-         units of the offset are node items.
+     (3) The 0x00600000 bits are spare.
 
-     (2) The 0x0fff bits of f2 contain the signed offset from this character to
-         its alternate cased value. They are zero if there is no such
-         character.
+     (4) The 0x001fffff bits contain the code point. No Unicode code point will
+         ever be greater than 0x0010ffff, so this should be OK for ever.
 
+(f1) (1) The 0xfc000000 bits contain the character type number. The numbers are
+         defined by an enum in ucp.h.
 
------------------------------------------------------------------------------
-||.|.| type (6) | ms char (8) ||  ls char (16)  ||....|  case offset (12)  ||
------------------------------------------------------------------------------
-  | |                                              |
-  | |-> spare                                      |
-  |                                        exponent of right
-  |-> left child exists                       child offset
+     (2) The 0x03ff0000 bits are spare.
 
+     (3) The 0x0000ffff bits contain EITHER the unsigned offset to the top of
+         range if this entry defines a range, OR the *signed* offset to the
+         character's "other case" partner if this entry defines a single
+         character. There is no partner if the value is zero.
 
-The upper/lower casing information is set only for characters that come in
-pairs. There are (at present) four non-one-to-one mappings in the Unicode data.
-These are ignored. They are:
+-------------------------------------------------------------------------------
+| script (8) |.|.|.| codepoint (21) || type (6) |.|.| spare (8) | offset (16) |
+-------------------------------------------------------------------------------
+              | | |                              | |
+              | | |-> spare                      | |-> spare
+              | |                                |
+              | |-> spare                        |-> spare
+              |
+              |-> range flag
 
-  1FBE Greek Prosgegrammeni (lower, with upper -> capital iota)
-  2126 Ohm
-  212A Kelvin
-  212B Angstrom
+The upper/lower casing information is set only for characters that come in
+pairs. The non-one-to-one mappings in the Unicode data are ignored.
 
-Certainly for the last three, having an alternate case would seem to be a
-mistake. I don't know any Greek, so cannot comment on the first one.
+When searching the data, proceed as follows:
 
+(1) Set up for a binary chop search.
 
-When searching the tree, proceed as follows:
+(2) If the top is not greater than the bottom, the character is not in the
+    table. Its type must therefore be "Cn" ("Undefined").
 
-(1) Start at the first node.
+(3) Find the middle vector element.
 
-(2) Extract the character value from f1 and the bottom 8 bits of f0;
+(4) Extract the code point and compare. If equal, we are done.
 
-(3) Compare with the character being sought. If equal, we are done.
+(5) If the test character is smaller, set the top to the current point, and
+    goto (2).
 
-(4) If the test character is smaller, inspect the f0_leftexists flag. If it is
-    not set, the character is not in the tree. If it is set, move to the next
-    node, and go to (2).
+(6) If the current entry defines a range, compute the last character by adding
+    the offset, and see if the test character is within the range. If it is,
+    we are done.
 
-(5) If the test character is bigger, extract the f2_rightmask bits from f2, and
-    shift them right by f2_rightshift. If the result is zero, the character is
-    not in the tree. Otherwise, calculate the number of nodes to skip by
-    shifting the value 1 left by this number minus one. Go to (2).
+(7) Otherwise, set the bottom to one element past the current point and goto
+    (2).
 */
 
-
-/* End of internal.h */
+/* End of ucpinternal.h */