-+ printk("<3>Regexp: %s\n", s);
-+ /* NOTREACHED */
-+}
-+
-+/*
-+ * The "internal use only" fields in regexp.h are present to pass info from
-+ * compile to execute that permits the execute phase to run lots faster on
-+ * simple cases. They are:
-+ *
-+ * regstart char that must begin a match; '\0' if none obvious
-+ * reganch is the match anchored (at beginning-of-line only)?
-+ * regmust string (pointer into program) that match must include, or NULL
-+ * regmlen length of regmust string
-+ *
-+ * Regstart and reganch permit very fast decisions on suitable starting points
-+ * for a match, cutting down the work a lot. Regmust permits fast rejection
-+ * of lines that cannot possibly match. The regmust tests are costly enough
-+ * that regcomp() supplies a regmust only if the r.e. contains something
-+ * potentially expensive (at present, the only such thing detected is * or +
-+ * at the start of the r.e., which can involve a lot of backup). Regmlen is
-+ * supplied because the test in regexec() needs it and regcomp() is computing
-+ * it anyway.
-+ */
-+
-+/*
-+ * Structure for regexp "program". This is essentially a linear encoding
-+ * of a nondeterministic finite-state machine (aka syntax charts or
-+ * "railroad normal form" in parsing technology). Each node is an opcode
-+ * plus a "next" pointer, possibly plus an operand. "Next" pointers of
-+ * all nodes except BRANCH implement concatenation; a "next" pointer with
-+ * a BRANCH on both ends of it is connecting two alternatives. (Here we
-+ * have one of the subtle syntax dependencies: an individual BRANCH (as
-+ * opposed to a collection of them) is never concatenated with anything
-+ * because of operator precedence.) The operand of some types of node is
-+ * a literal string; for others, it is a node leading into a sub-FSM. In
-+ * particular, the operand of a BRANCH node is the first node of the branch.
-+ * (NB this is *not* a tree structure: the tail of the branch connects
-+ * to the thing following the set of BRANCHes.) The opcodes are:
-+ */
-+
-+/* definition number opnd? meaning */
-+#define END 0 /* no End of program. */
-+#define BOL 1 /* no Match "" at beginning of line. */
-+#define EOL 2 /* no Match "" at end of line. */
-+#define ANY 3 /* no Match any one character. */
-+#define ANYOF 4 /* str Match any character in this string. */
-+#define ANYBUT 5 /* str Match any character not in this string. */
-+#define BRANCH 6 /* node Match this alternative, or the next... */
-+#define BACK 7 /* no Match "", "next" ptr points backward. */
-+#define EXACTLY 8 /* str Match this string. */
-+#define NOTHING 9 /* no Match empty string. */
-+#define STAR 10 /* node Match this (simple) thing 0 or more times. */
-+#define PLUS 11 /* node Match this (simple) thing 1 or more times. */
-+#define OPEN 20 /* no Mark this point in input as start of #n. */
-+ /* OPEN+1 is number 1, etc. */
-+#define CLOSE 30 /* no Analogous to OPEN. */
-+
-+/*
-+ * Opcode notes:
-+ *
-+ * BRANCH The set of branches constituting a single choice are hooked
-+ * together with their "next" pointers, since precedence prevents
-+ * anything being concatenated to any individual branch. The
-+ * "next" pointer of the last BRANCH in a choice points to the
-+ * thing following the whole choice. This is also where the
-+ * final "next" pointer of each individual branch points; each
-+ * branch starts with the operand node of a BRANCH node.
-+ *
-+ * BACK Normal "next" pointers all implicitly point forward; BACK
-+ * exists to make loop structures possible.
-+ *
-+ * STAR,PLUS '?', and complex '*' and '+', are implemented as circular
-+ * BRANCH structures using BACK. Simple cases (one character
-+ * per match) are implemented with STAR and PLUS for speed
-+ * and to minimize recursive plunges.
-+ *
-+ * OPEN,CLOSE ...are numbered at compile time.
-+ */
-+
-+/*
-+ * A node is one char of opcode followed by two chars of "next" pointer.
-+ * "Next" pointers are stored as two 8-bit pieces, high order first. The
-+ * value is a positive offset from the opcode of the node containing it.
-+ * An operand, if any, simply follows the node. (Note that much of the
-+ * code generation knows about this implicit relationship.)
-+ *
-+ * Using two bytes for the "next" pointer is vast overkill for most things,
-+ * but allows patterns to get big without disasters.
-+ */
-+#define OP(p) (*(p))
-+#define NEXT(p) (((*((p)+1)&0377)<<8) + (*((p)+2)&0377))
-+#define OPERAND(p) ((p) + 3)
-+
-+/*
-+ * See regmagic.h for one further detail of program structure.
-+ */
-+
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