lregex.c

ctags的最新版5.7,可以比较5.6版看看,免费下载

/*
*   $Id: lregex.c 576 2007-06-30 04:16:23Z elliotth $
*
*   Copyright (c) 2000-2003, Darren Hiebert
*
*   This source code is released for free distribution under the terms of the
*   GNU General Public License.
*
*   This module contains functions for applying regular expression matching.
*
*   The code for utlizing the Gnu regex package with regards to processing the
*   regex option and checking for regex matches was adapted from routines in
*   Gnu etags.
*/

/*
*   INCLUDE FILES
*/
#include "general.h"  /* must always come first */

#include <string.h>

#ifdef HAVE_REGCOMP
# include <ctype.h>
# include <stddef.h>
# ifdef HAVE_SYS_TYPES_H
#  include <sys/types.h>  /* declare off_t (not known to regex.h on FreeBSD) */
# endif
# include <regex.h>
#endif

#include "debug.h"
#include "entry.h"
#include "parse.h"
#include "read.h"
#include "routines.h"

#ifdef HAVE_REGEX

/*
*   MACROS
*/

/* Back-references \0 through \9 */
#define BACK_REFERENCE_COUNT 10

#if defined (HAVE_REGCOMP) && !defined (REGCOMP_BROKEN)
# define POSIX_REGEX
#endif

#define REGEX_NAME "Regex"

/*
*   DATA DECLARATIONS
*/
#if defined (POSIX_REGEX)

struct sKind {
	boolean enabled;
	char letter;
	char* name;
	char* description;
};

enum pType { PTRN_TAG, PTRN_CALLBACK };

typedef struct {
	regex_t *pattern;
	enum pType type;
	union {
		struct {
			char *name_pattern;
			struct sKind kind;
		} tag;
		struct {
			regexCallback function;
		} callback;
	} u;
} regexPattern;

#endif

typedef struct {
	regexPattern *patterns;
	unsigned int count;
} patternSet;

/*
*   DATA DEFINITIONS
*/

static boolean regexBroken = FALSE;

/* Array of pattern sets, indexed by language */
static patternSet* Sets = NULL;
static int SetUpper = -1;  /* upper language index in list */

/*
*   FUNCTION DEFINITIONS
*/

static void clearPatternSet (const langType language)
{
	if (language <= SetUpper)
	{
		patternSet* const set = Sets + language;
		unsigned int i;
		for (i = 0  ;  i < set->count  ;  ++i)
		{
			regexPattern *p = &set->patterns [i];
#if defined (POSIX_REGEX)
			regfree (p->pattern);
#endif
			eFree (p->pattern);
			p->pattern = NULL;

			if (p->type == PTRN_TAG)
			{
				eFree (p->u.tag.name_pattern);
				p->u.tag.name_pattern = NULL;
				eFree (p->u.tag.kind.name);
				p->u.tag.kind.name = NULL;
				if (p->u.tag.kind.description != NULL)
				{
					eFree (p->u.tag.kind.description);
					p->u.tag.kind.description = NULL;
				}
			}
		}
		if (set->patterns != NULL)
			eFree (set->patterns);
		set->patterns = NULL;
		set->count = 0;
	}
}

/*
*   Regex psuedo-parser
*/

static void makeRegexTag (
		const vString* const name, const struct sKind* const kind)
{
	if (kind->enabled)
	{
		tagEntryInfo e;
		Assert (name != NULL  &&  vStringLength (name) > 0);
		Assert (kind != NULL);
		initTagEntry (&e, vStringValue (name));
		e.kind     = kind->letter;
		e.kindName = kind->name;
		makeTagEntry (&e);
	}
}

/*
*   Regex pattern definition
*/

/* Take a string like "/blah/" and turn it into "blah", making sure
 * that the first and last characters are the same, and handling
 * quoted separator characters.  Actually, stops on the occurrence of
 * an unquoted separator.  Also turns "\t" into a Tab character.
 * Returns pointer to terminating separator.  Works in place.  Null
 * terminates name string.
 */
static char* scanSeparators (char* name)
{
	char sep = name [0];
	char *copyto = name;
	boolean quoted = FALSE;

	for (++name ; *name != '\0' ; ++name)
	{
		if (quoted)
		{
			if (*name == sep)
				*copyto++ = sep;
			else if (*name == 't')
				*copyto++ = '\t';
			else
			{
				/* Something else is quoted, so preserve the quote. */
				*copyto++ = '\\';
				*copyto++ = *name;
			}
			quoted = FALSE;
		}
		else if (*name == '\\')
			quoted = TRUE;
		else if (*name == sep)
		{
			break;
		}
		else
			*copyto++ = *name;
	}
	*copyto = '\0';
	return name;
}

/* Parse `regexp', in form "/regex/name/[k,Kind/]flags" (where the separator
 * character is whatever the first character of `regexp' is), by breaking it
 * up into null terminated strings, removing the separators, and expanding
 * '\t' into tabs. When complete, `regexp' points to the line matching
 * pattern, a pointer to the name matching pattern is written to `name', a
 * pointer to the kinds is written to `kinds' (possibly NULL), and a pointer
 * to the trailing flags is written to `flags'. If the pattern is not in the
 * correct format, a false value is returned.
 */
static boolean parseTagRegex (
		char* const regexp, char** const name,
		char** const kinds, char** const flags)
{
	boolean result = FALSE;
	const int separator = (unsigned char) regexp [0];

	*name = scanSeparators (regexp);
	if (*regexp == '\0')
		error (WARNING, "empty regexp");
	else if (**name != separator)
		error (WARNING, "%s: incomplete regexp", regexp);
	else
	{
		char* const third = scanSeparators (*name);
		if (**name == '\0')
			error (WARNING, "%s: regexp missing name pattern", regexp);
		if ((*name) [strlen (*name) - 1] == '\\')
			error (WARNING, "error in name pattern: \"%s\"", *name);
		if (*third != separator)
			error (WARNING, "%s: regexp missing final separator", regexp);
		else
		{
			char* const fourth = scanSeparators (third);
			if (*fourth == separator)
			{
				*kinds = third;
				scanSeparators (fourth);
				*flags = fourth;
			}
			else
			{
				*flags = third;
				*kinds = NULL;
			}
			result = TRUE;
		}
	}
	return result;
}

static void addCompiledTagPattern (
		const langType language, regex_t* const pattern,
		char* const name, const char kind, char* const kindName,
		char *const description)
{
	patternSet* set;
	regexPattern *ptrn;
	if (language > SetUpper)
	{
		int i;
		Sets = xRealloc (Sets, (language + 1), patternSet);
		for (i = SetUpper + 1  ;  i <= language  ;  ++i)
		{
			Sets [i].patterns = NULL;
			Sets [i].count = 0;
		}
		SetUpper = language;
	}
	set = Sets + language;
	set->patterns = xRealloc (set->patterns, (set->count + 1), regexPattern);
	ptrn = &set->patterns [set->count];
	set->count += 1;

	ptrn->pattern = pattern;
	ptrn->type    = PTRN_TAG;
	ptrn->u.tag.name_pattern = name;
	ptrn->u.tag.kind.enabled = TRUE;
	ptrn->u.tag.kind.letter  = kind;
	ptrn->u.tag.kind.name    = kindName;
	ptrn->u.tag.kind.description = description;
}

static void addCompiledCallbackPattern (
		const langType language, regex_t* const pattern,
		const regexCallback callback)
{
	patternSet* set;
	regexPattern *ptrn;
	if (language > SetUpper)
	{
		int i;
		Sets = xRealloc (Sets, (language + 1), patternSet);
		for (i = SetUpper + 1  ;  i <= language  ;  ++i)
		{
			Sets [i].patterns = NULL;
			Sets [i].count = 0;
		}
		SetUpper = language;
	}
	set = Sets + language;
	set->patterns = xRealloc (set->patterns, (set->count + 1), regexPattern);
	ptrn = &set->patterns [set->count];
	set->count += 1;

	ptrn->pattern = pattern;
	ptrn->type    = PTRN_CALLBACK;
	ptrn->u.callback.function = callback;
}

#if defined (POSIX_REGEX)

static regex_t* compileRegex (const char* const regexp, const char* const flags)
{
	int cflags = REG_EXTENDED | REG_NEWLINE;
	regex_t *result = NULL;
	int errcode;
	int i;
	for (i = 0  ; flags != NULL  &&  flags [i] != '\0'  ;  ++i)
	{
		switch ((int) flags [i])
		{
			case 'b': cflags &= ~REG_EXTENDED; break;
			case 'e': cflags |= REG_EXTENDED;  break;
			case 'i': cflags |= REG_ICASE;     break;
			default: error (WARNING, "unknown regex flag: '%c'", *flags); break;
		}
	}
	result = xMalloc (1, regex_t);
	errcode = regcomp (result, regexp, cflags);
	if (errcode != 0)
	{
		char errmsg[256];
		regerror (errcode, result, errmsg, 256);
		error (WARNING, "regcomp %s: %s", regexp, errmsg);
		regfree (result);
		eFree (result);
		result = NULL;
	}
	return result;
}

#endif

static void parseKinds (
		const char* const kinds, char* const kind, char** const kindName,
		char **description)
{
	*kind = '\0';
	*kindName = NULL;
	*description = NULL;
	if (kinds == NULL  ||  kinds [0] == '\0')
	{