POSIX-compatible regex interface

With some ARE extensions

Signed-off-by: Steve Bennett <steveb@workware.net.au>

1 files changed, 111 insertions, 0 deletions

diff --git a/jimregexp.h b/jimregexp.h
new file mode 100644
index 0000000..751bbf7
--- /dev/null
+++ b/jimregexp.h
@@ -0,0 +1,111 @@
+#ifndef JIMREGEXP_H
+#define JIMREGEXP_H
+
+#if defined(HAVE_REGCOMP) && !defined(JIM_REGEXP)
+/* Use POSIX regex */
+#include <regex.h>
+
+#else
+
+#include <stdlib.h>
+
+/*
+ * Definitions etc. for regexp(3) routines.
+ *
+ * Caveat:  this is V8 regexp(3) [actually, a reimplementation thereof],
+ * not the System V one.
+ *
+ * 11/04/02 (seiwald) - const-ing for string literals
+ */
+
+typedef struct {
+	int rm_so;
+	int rm_eo;
+} regmatch_t;
+
+/*
+ * 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.
+ */
+
+typedef struct regexp {
+	/* -- public -- */
+	int re_nsub;		/* number of parenthesized subexpressions */
+
+	/* -- private -- */
+	int cflags;			/* Flags used when compiling */
+	int err;			/* Any error which occurred during compile */
+	char regstart;		/* Internal use only. */
+	char reganch;		/* Internal use only. */
+	const char *regmust;		/* Internal use only. */
+	int regmlen;		/* Internal use only. */
+	char *program;		/* Allocated */
+
+	/* working state - compile */
+	const char *regparse;		/* Input-scan pointer. */
+	char *regcode;		/* Code-emit pointer; &regdummy = don't. */
+	long regsize;		/* Code size. */
+
+	/* working state - exec */
+	int eflags;				/* Flags used when executing */
+	const char *start;		/* Initial string pointer. */
+	const char *reginput;	/* Current input pointer. */
+	const char *regbol;		/* Beginning of input, for ^ check. */
+
+	/* Input to regexec() */
+	regmatch_t *pmatch;		/* submatches will be stored here */
+	int nmatch;				/* size of pmatch[] */
+} regexp;
+
+typedef regexp regex_t;
+
+#define REG_EXTENDED 0
+#define REG_NEWLINE 1
+#define REG_ICASE 2
+
+#define REG_NOTBOL 16
+
+enum {
+	REG_NOERROR,      /* Success.  */
+	REG_NOMATCH,      /* Didn't find a match (for regexec).  */
+	REG_BADPAT,		  /* >= REG_BADPAT is an error */
+	REG_ERR_NULL_ARGUMENT,
+	REG_ERR_UNKNOWN,
+	REG_ERR_TOO_BIG,
+	REG_ERR_NOMEM,
+	REG_ERR_TOO_MANY_PAREN,
+	REG_ERR_UNMATCHED_PAREN,
+	REG_ERR_JUNK_ON_END,
+	REG_ERR_OPERAND_COULD_BE_EMPTY,
+	REG_ERR_NESTED_COUNT,
+	REG_ERR_INTERNAL,
+	REG_ERR_COUNT_FOLLOWS_NOTHING,
+	REG_ERR_TRAILING_BACKSLASH,
+	REG_ERR_CORRUPTED,
+	REG_ERR_COUNT_UNSUPPORTED,
+	REG_ERR_NUM
+};
+
+int regcomp(regex_t *preg, const char *regex, int cflags);
+int regexec(regex_t  *preg,  const  char *string, size_t nmatch, regmatch_t pmatch[], int eflags);
+size_t regerror(int errcode, const regex_t *preg, char *errbuf,  size_t errbuf_size);
+void regfree(regex_t *preg);
+
+#endif
+
+#endif