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Diffstat (limited to 'generic/tclRegexp.c')
| -rw-r--r-- | generic/tclRegexp.c | 1073 |
1 files changed, 1073 insertions, 0 deletions
diff --git a/generic/tclRegexp.c b/generic/tclRegexp.c new file mode 100644 index 0000000..6348e4a --- /dev/null +++ b/generic/tclRegexp.c @@ -0,0 +1,1073 @@ +/* + * tclRegexp.c -- + * + * This file contains the public interfaces to the Tcl regular expression + * mechanism. + * + * Copyright (c) 1998 by Sun Microsystems, Inc. + * Copyright (c) 1998-1999 by Scriptics Corporation. + * + * See the file "license.terms" for information on usage and redistribution of + * this file, and for a DISCLAIMER OF ALL WARRANTIES. + */ + +#include "tclInt.h" +#include "tclRegexp.h" + +/* + *---------------------------------------------------------------------- + * The routines in this file use Henry Spencer's regular expression package + * contained in the following additional source files: + * + * regc_color.c regc_cvec.c regc_lex.c + * regc_nfa.c regcomp.c regcustom.h + * rege_dfa.c regerror.c regerrs.h + * regex.h regexec.c regfree.c + * regfronts.c regguts.h + * + * Copyright (c) 1998 Henry Spencer. All rights reserved. + * + * Development of this software was funded, in part, by Cray Research Inc., + * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics + * Corporation, none of whom are responsible for the results. The author + * thanks all of them. + * + * Redistribution and use in source and binary forms -- with or without + * modification -- are permitted for any purpose, provided that + * redistributions in source form retain this entire copyright notice and + * indicate the origin and nature of any modifications. + * + * I'd appreciate being given credit for this package in the documentation of + * software which uses it, but that is not a requirement. + * + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL + * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; + * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * *** NOTE: this code has been altered slightly for use in Tcl: *** + * *** 1. Names have been changed, e.g. from re_comp to *** + * *** TclRegComp, to avoid clashes with other *** + * *** regexp implementations used by applications. *** + */ + +/* + * Thread local storage used to maintain a per-thread cache of compiled + * regular expressions. + */ + +#define NUM_REGEXPS 30 + +typedef struct ThreadSpecificData { + int initialized; /* Set to 1 when the module is initialized. */ + char *patterns[NUM_REGEXPS];/* Strings corresponding to compiled regular + * expression patterns. NULL means that this + * slot isn't used. Malloc-ed. */ + int patLengths[NUM_REGEXPS];/* Number of non-null characters in + * corresponding entry in patterns. -1 means + * entry isn't used. */ + struct TclRegexp *regexps[NUM_REGEXPS]; + /* Compiled forms of above strings. Also + * malloc-ed, or NULL if not in use yet. */ +} ThreadSpecificData; + +static Tcl_ThreadDataKey dataKey; + +/* + * Declarations for functions used only in this file. + */ + +static TclRegexp * CompileRegexp(Tcl_Interp *interp, const char *pattern, + int length, int flags); +static void DupRegexpInternalRep(Tcl_Obj *srcPtr, + Tcl_Obj *copyPtr); +static void FinalizeRegexp(ClientData clientData); +static void FreeRegexp(TclRegexp *regexpPtr); +static void FreeRegexpInternalRep(Tcl_Obj *objPtr); +static int RegExpExecUniChar(Tcl_Interp *interp, Tcl_RegExp re, + const Tcl_UniChar *uniString, int numChars, + int nmatches, int flags); +static int SetRegexpFromAny(Tcl_Interp *interp, Tcl_Obj *objPtr); + +/* + * The regular expression Tcl object type. This serves as a cache of the + * compiled form of the regular expression. + */ + +const Tcl_ObjType tclRegexpType = { + "regexp", /* name */ + FreeRegexpInternalRep, /* freeIntRepProc */ + DupRegexpInternalRep, /* dupIntRepProc */ + NULL, /* updateStringProc */ + SetRegexpFromAny /* setFromAnyProc */ +}; + +/* + *---------------------------------------------------------------------- + * + * Tcl_RegExpCompile -- + * + * Compile a regular expression into a form suitable for fast matching. + * This function is DEPRECATED in favor of the object version of the + * command. + * + * Results: + * The return value is a pointer to the compiled form of string, suitable + * for passing to Tcl_RegExpExec. This compiled form is only valid up + * until the next call to this function, so don't keep these around for a + * long time! If an error occurred while compiling the pattern, then NULL + * is returned and an error message is left in the interp's result. + * + * Side effects: + * Updates the cache of compiled regexps. + * + *---------------------------------------------------------------------- + */ + +Tcl_RegExp +Tcl_RegExpCompile( + Tcl_Interp *interp, /* For use in error reporting and to access + * the interp regexp cache. */ + const char *pattern) /* String for which to produce compiled + * regular expression. */ +{ + return (Tcl_RegExp) CompileRegexp(interp, pattern, (int) strlen(pattern), + REG_ADVANCED); +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_RegExpExec -- + * + * Execute the regular expression matcher using a compiled form of a + * regular expression and save information about any match that is found. + * + * Results: + * If an error occurs during the matching operation then -1 is returned + * and the interp's result contains an error message. Otherwise the + * return value is 1 if a matching range is found and 0 if there is no + * matching range. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_RegExpExec( + Tcl_Interp *interp, /* Interpreter to use for error reporting. */ + Tcl_RegExp re, /* Compiled regular expression; must have been + * returned by previous call to + * Tcl_GetRegExpFromObj. */ + const char *text, /* Text against which to match re. */ + const char *start) /* If text is part of a larger string, this + * identifies beginning of larger string, so + * that "^" won't match. */ +{ + int flags, result, numChars; + TclRegexp *regexp = (TclRegexp *) re; + Tcl_DString ds; + const Tcl_UniChar *ustr; + + /* + * If the starting point is offset from the beginning of the buffer, then + * we need to tell the regexp engine not to match "^". + */ + + if (text > start) { + flags = REG_NOTBOL; + } else { + flags = 0; + } + + /* + * Remember the string for use by Tcl_RegExpRange(). + */ + + regexp->string = text; + regexp->objPtr = NULL; + + /* + * Convert the string to Unicode and perform the match. + */ + + Tcl_DStringInit(&ds); + ustr = Tcl_UtfToUniCharDString(text, -1, &ds); + numChars = Tcl_DStringLength(&ds) / sizeof(Tcl_UniChar); + result = RegExpExecUniChar(interp, re, ustr, numChars, -1 /* nmatches */, + flags); + Tcl_DStringFree(&ds); + + return result; +} + +/* + *--------------------------------------------------------------------------- + * + * Tcl_RegExpRange -- + * + * Returns pointers describing the range of a regular expression match, + * or one of the subranges within the match. + * + * Results: + * The variables at *startPtr and *endPtr are modified to hold the + * addresses of the endpoints of the range given by index. If the + * specified range doesn't exist then NULLs are returned. + * + * Side effects: + * None. + * + *--------------------------------------------------------------------------- + */ + +void +Tcl_RegExpRange( + Tcl_RegExp re, /* Compiled regular expression that has been + * passed to Tcl_RegExpExec. */ + int index, /* 0 means give the range of the entire match, + * > 0 means give the range of a matching + * subrange. */ + const char **startPtr, /* Store address of first character in + * (sub-)range here. */ + const char **endPtr) /* Store address of character just after last + * in (sub-)range here. */ +{ + TclRegexp *regexpPtr = (TclRegexp *) re; + const char *string; + + if ((size_t) index > regexpPtr->re.re_nsub) { + *startPtr = *endPtr = NULL; + } else if (regexpPtr->matches[index].rm_so < 0) { + *startPtr = *endPtr = NULL; + } else { + if (regexpPtr->objPtr) { + string = TclGetString(regexpPtr->objPtr); + } else { + string = regexpPtr->string; + } + *startPtr = Tcl_UtfAtIndex(string, regexpPtr->matches[index].rm_so); + *endPtr = Tcl_UtfAtIndex(string, regexpPtr->matches[index].rm_eo); + } +} + +/* + *--------------------------------------------------------------------------- + * + * RegExpExecUniChar -- + * + * Execute the regular expression matcher using a compiled form of a + * regular expression and save information about any match that is found. + * + * Results: + * If an error occurs during the matching operation then -1 is returned + * and an error message is left in interp's result. Otherwise the return + * value is 1 if a matching range was found or 0 if there was no matching + * range. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static int +RegExpExecUniChar( + Tcl_Interp *interp, /* Interpreter to use for error reporting. */ + Tcl_RegExp re, /* Compiled regular expression; returned by a + * previous call to Tcl_GetRegExpFromObj */ + const Tcl_UniChar *wString, /* String against which to match re. */ + int numChars, /* Length of Tcl_UniChar string (must be + * >=0). */ + int nmatches, /* How many subexpression matches (counting + * the whole match as subexpression 0) are of + * interest. -1 means "don't know". */ + int flags) /* Regular expression flags. */ +{ + int status; + TclRegexp *regexpPtr = (TclRegexp *) re; + size_t last = regexpPtr->re.re_nsub + 1; + size_t nm = last; + + if (nmatches >= 0 && (size_t) nmatches < nm) { + nm = (size_t) nmatches; + } + + status = TclReExec(®expPtr->re, wString, (size_t) numChars, + ®expPtr->details, nm, regexpPtr->matches, flags); + + /* + * Check for errors. + */ + + if (status != REG_OKAY) { + if (status == REG_NOMATCH) { + return 0; + } + if (interp != NULL) { + TclRegError(interp, "error while matching regular expression: ", + status); + } + return -1; + } + return 1; +} + +/* + *--------------------------------------------------------------------------- + * + * TclRegExpRangeUniChar -- + * + * Returns pointers describing the range of a regular expression match, + * or one of the subranges within the match, or the hypothetical range + * represented by the rm_extend field of the rm_detail_t. + * + * Results: + * The variables at *startPtr and *endPtr are modified to hold the + * offsets of the endpoints of the range given by index. If the specified + * range doesn't exist then -1s are supplied. + * + * Side effects: + * None. + * + *--------------------------------------------------------------------------- + */ + +void +TclRegExpRangeUniChar( + Tcl_RegExp re, /* Compiled regular expression that has been + * passed to Tcl_RegExpExec. */ + int index, /* 0 means give the range of the entire match, + * > 0 means give the range of a matching + * subrange, -1 means the range of the + * rm_extend field. */ + int *startPtr, /* Store address of first character in + * (sub-)range here. */ + int *endPtr) /* Store address of character just after last + * in (sub-)range here. */ +{ + TclRegexp *regexpPtr = (TclRegexp *) re; + + if ((regexpPtr->flags®_EXPECT) && index == -1) { + *startPtr = regexpPtr->details.rm_extend.rm_so; + *endPtr = regexpPtr->details.rm_extend.rm_eo; + } else if ((size_t) index > regexpPtr->re.re_nsub) { + *startPtr = -1; + *endPtr = -1; + } else { + *startPtr = regexpPtr->matches[index].rm_so; + *endPtr = regexpPtr->matches[index].rm_eo; + } +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_RegExpMatch -- + * + * See if a string matches a regular expression. + * + * Results: + * If an error occurs during the matching operation then -1 is returned + * and the interp's result contains an error message. Otherwise the + * return value is 1 if "text" matches "pattern" and 0 otherwise. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_RegExpMatch( + Tcl_Interp *interp, /* Used for error reporting. May be NULL. */ + const char *text, /* Text to search for pattern matches. */ + const char *pattern) /* Regular expression to match against text. */ +{ + Tcl_RegExp re = Tcl_RegExpCompile(interp, pattern); + + if (re == NULL) { + return -1; + } + return Tcl_RegExpExec(interp, re, text, text); +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_RegExpExecObj -- + * + * Execute a precompiled regexp against the given object. + * + * Results: + * If an error occurs during the matching operation then -1 is returned + * and the interp's result contains an error message. Otherwise the + * return value is 1 if "string" matches "pattern" and 0 otherwise. + * + * Side effects: + * Converts the object to a Unicode object. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_RegExpExecObj( + Tcl_Interp *interp, /* Interpreter to use for error reporting. */ + Tcl_RegExp re, /* Compiled regular expression; must have been + * returned by previous call to + * Tcl_GetRegExpFromObj. */ + Tcl_Obj *textObj, /* Text against which to match re. */ + int offset, /* Character index that marks where matching + * should begin. */ + int nmatches, /* How many subexpression matches (counting + * the whole match as subexpression 0) are of + * interest. -1 means all of them. */ + int flags) /* Regular expression execution flags. */ +{ + TclRegexp *regexpPtr = (TclRegexp *) re; + Tcl_UniChar *udata; + int length; + int reflags = regexpPtr->flags; +#define TCL_REG_GLOBOK_FLAGS \ + (TCL_REG_ADVANCED | TCL_REG_NOSUB | TCL_REG_NOCASE) + + /* + * Take advantage of the equivalent glob pattern, if one exists. + * This is possible based only on the right mix of incoming flags (0) + * and regexp compile flags. + */ + if ((offset == 0) && (nmatches == 0) && (flags == 0) + && !(reflags & ~TCL_REG_GLOBOK_FLAGS) + && (regexpPtr->globObjPtr != NULL)) { + int nocase = (reflags & TCL_REG_NOCASE) ? TCL_MATCH_NOCASE : 0; + + /* + * Pass to TclStringMatchObj for obj-specific handling. + * XXX: Currently doesn't take advantage of exact-ness that + * XXX: TclReToGlob tells us about + */ + + return TclStringMatchObj(textObj, regexpPtr->globObjPtr, nocase); + } + + /* + * Save the target object so we can extract strings from it later. + */ + + regexpPtr->string = NULL; + regexpPtr->objPtr = textObj; + + udata = Tcl_GetUnicodeFromObj(textObj, &length); + + if (offset > length) { + offset = length; + } + udata += offset; + length -= offset; + + return RegExpExecUniChar(interp, re, udata, length, nmatches, flags); +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_RegExpMatchObj -- + * + * See if an object matches a regular expression. + * + * Results: + * If an error occurs during the matching operation then -1 is returned + * and the interp's result contains an error message. Otherwise the + * return value is 1 if "text" matches "pattern" and 0 otherwise. + * + * Side effects: + * Changes the internal rep of the pattern and string objects. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_RegExpMatchObj( + Tcl_Interp *interp, /* Used for error reporting. May be NULL. */ + Tcl_Obj *textObj, /* Object containing the String to search. */ + Tcl_Obj *patternObj) /* Regular expression to match against + * string. */ +{ + Tcl_RegExp re; + + re = Tcl_GetRegExpFromObj(interp, patternObj, + TCL_REG_ADVANCED | TCL_REG_NOSUB); + if (re == NULL) { + return -1; + } + return Tcl_RegExpExecObj(interp, re, textObj, 0 /* offset */, + 0 /* nmatches */, 0 /* flags */); +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_RegExpGetInfo -- + * + * Retrieve information about the current match. + * + * Results: + * None. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +void +Tcl_RegExpGetInfo( + Tcl_RegExp regexp, /* Pattern from which to get subexpressions. */ + Tcl_RegExpInfo *infoPtr) /* Match information is stored here. */ +{ + TclRegexp *regexpPtr = (TclRegexp *) regexp; + + infoPtr->nsubs = regexpPtr->re.re_nsub; + infoPtr->matches = (Tcl_RegExpIndices *) regexpPtr->matches; + infoPtr->extendStart = regexpPtr->details.rm_extend.rm_so; +} + +/* + *---------------------------------------------------------------------- + * + * Tcl_GetRegExpFromObj -- + * + * Compile a regular expression into a form suitable for fast matching. + * This function caches the result in a Tcl_Obj. + * + * Results: + * The return value is a pointer to the compiled form of string, suitable + * for passing to Tcl_RegExpExec. If an error occurred while compiling + * the pattern, then NULL is returned and an error message is left in the + * interp's result. + * + * Side effects: + * Updates the native rep of the Tcl_Obj. + * + *---------------------------------------------------------------------- + */ + +Tcl_RegExp +Tcl_GetRegExpFromObj( + Tcl_Interp *interp, /* For use in error reporting, and to access + * the interp regexp cache. */ + Tcl_Obj *objPtr, /* Object whose string rep contains regular + * expression pattern. Internal rep will be + * changed to compiled form of this regular + * expression. */ + int flags) /* Regular expression compilation flags. */ +{ + int length; + TclRegexp *regexpPtr; + const char *pattern; + + /* + * This is OK because we only actually interpret this value properly as a + * TclRegexp* when the type is tclRegexpType. + */ + + regexpPtr = objPtr->internalRep.twoPtrValue.ptr1; + + if ((objPtr->typePtr != &tclRegexpType) || (regexpPtr->flags != flags)) { + pattern = TclGetStringFromObj(objPtr, &length); + + regexpPtr = CompileRegexp(interp, pattern, length, flags); + if (regexpPtr == NULL) { + return NULL; + } + + /* + * Add a reference to the regexp so it will persist even if it is + * pushed out of the current thread's regexp cache. This reference + * will be removed when the object's internal rep is freed. + */ + + regexpPtr->refCount++; + + /* + * Free the old representation and set our type. + */ + + TclFreeIntRep(objPtr); + objPtr->internalRep.twoPtrValue.ptr1 = regexpPtr; + objPtr->typePtr = &tclRegexpType; + } + return (Tcl_RegExp) regexpPtr; +} + +/* + *---------------------------------------------------------------------- + * + * TclRegAbout -- + * + * Return information about a compiled regular expression. + * + * Results: + * The return value is -1 for failure, 0 for success, although at the + * moment there's nothing that could fail. On success, a list is left in + * the interp's result: first element is the subexpression count, second + * is a list of re_info bit names. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +int +TclRegAbout( + Tcl_Interp *interp, /* For use in variable assignment. */ + Tcl_RegExp re) /* The compiled regular expression. */ +{ + TclRegexp *regexpPtr = (TclRegexp *) re; + struct infoname { + int bit; + const char *text; + }; + static const struct infoname infonames[] = { + {REG_UBACKREF, "REG_UBACKREF"}, + {REG_ULOOKAHEAD, "REG_ULOOKAHEAD"}, + {REG_UBOUNDS, "REG_UBOUNDS"}, + {REG_UBRACES, "REG_UBRACES"}, + {REG_UBSALNUM, "REG_UBSALNUM"}, + {REG_UPBOTCH, "REG_UPBOTCH"}, + {REG_UBBS, "REG_UBBS"}, + {REG_UNONPOSIX, "REG_UNONPOSIX"}, + {REG_UUNSPEC, "REG_UUNSPEC"}, + {REG_UUNPORT, "REG_UUNPORT"}, + {REG_ULOCALE, "REG_ULOCALE"}, + {REG_UEMPTYMATCH, "REG_UEMPTYMATCH"}, + {REG_UIMPOSSIBLE, "REG_UIMPOSSIBLE"}, + {REG_USHORTEST, "REG_USHORTEST"}, + {0, NULL} + }; + const struct infoname *inf; + Tcl_Obj *infoObj, *resultObj; + + /* + * The reset here guarantees that the interpreter result is empty and + * unshared. This means that we can use Tcl_ListObjAppendElement on the + * result object quite safely. + */ + + Tcl_ResetResult(interp); + + /* + * Assume that there will never be more than INT_MAX subexpressions. This + * is a pretty reasonable assumption; the RE engine doesn't scale _that_ + * well and Tcl has other limits that constrain things as well... + */ + + resultObj = Tcl_NewObj(); + Tcl_ListObjAppendElement(NULL, resultObj, + Tcl_NewIntObj((int) regexpPtr->re.re_nsub)); + + /* + * Now append a list of all the bit-flags set for the RE. + */ + + TclNewObj(infoObj); + for (inf=infonames ; inf->bit != 0 ; inf++) { + if (regexpPtr->re.re_info & inf->bit) { + Tcl_ListObjAppendElement(NULL, infoObj, + Tcl_NewStringObj(inf->text, -1)); + } + } + Tcl_ListObjAppendElement(NULL, resultObj, infoObj); + Tcl_SetObjResult(interp, resultObj); + + return 0; +} + +/* + *---------------------------------------------------------------------- + * + * TclRegError -- + * + * Generate an error message based on the regexp status code. + * + * Results: + * Places an error in the interpreter. + * + * Side effects: + * Sets errorCode as well. + * + *---------------------------------------------------------------------- + */ + +void +TclRegError( + Tcl_Interp *interp, /* Interpreter for error reporting. */ + const char *msg, /* Message to prepend to error. */ + int status) /* Status code to report. */ +{ + char buf[100]; /* ample in practice */ + char cbuf[TCL_INTEGER_SPACE]; + size_t n; + const char *p; + + Tcl_ResetResult(interp); + n = TclReError(status, NULL, buf, sizeof(buf)); + p = (n > sizeof(buf)) ? "..." : ""; + Tcl_SetObjResult(interp, Tcl_ObjPrintf("%s%s%s", msg, buf, p)); + + sprintf(cbuf, "%d", status); + (void) TclReError(REG_ITOA, NULL, cbuf, sizeof(cbuf)); + Tcl_SetErrorCode(interp, "REGEXP", cbuf, buf, NULL); +} + +/* + *---------------------------------------------------------------------- + * + * FreeRegexpInternalRep -- + * + * Deallocate the storage associated with a regexp object's internal + * representation. + * + * Results: + * None. + * + * Side effects: + * Frees the compiled regular expression. + * + *---------------------------------------------------------------------- + */ + +static void +FreeRegexpInternalRep( + Tcl_Obj *objPtr) /* Regexp object with internal rep to free. */ +{ + TclRegexp *regexpRepPtr = objPtr->internalRep.twoPtrValue.ptr1; + + /* + * If this is the last reference to the regexp, free it. + */ + + if (--(regexpRepPtr->refCount) <= 0) { + FreeRegexp(regexpRepPtr); + } + objPtr->typePtr = NULL; +} + +/* + *---------------------------------------------------------------------- + * + * DupRegexpInternalRep -- + * + * We copy the reference to the compiled regexp and bump its reference + * count. + * + * Results: + * None. + * + * Side effects: + * Increments the reference count of the regexp. + * + *---------------------------------------------------------------------- + */ + +static void +DupRegexpInternalRep( + Tcl_Obj *srcPtr, /* Object with internal rep to copy. */ + Tcl_Obj *copyPtr) /* Object with internal rep to set. */ +{ + TclRegexp *regexpPtr = srcPtr->internalRep.twoPtrValue.ptr1; + + regexpPtr->refCount++; + copyPtr->internalRep.twoPtrValue.ptr1 = srcPtr->internalRep.twoPtrValue.ptr1; + copyPtr->typePtr = &tclRegexpType; +} + +/* + *---------------------------------------------------------------------- + * + * SetRegexpFromAny -- + * + * Attempt to generate a compiled regular expression for the Tcl object + * "objPtr". + * + * Results: + * The return value is TCL_OK or TCL_ERROR. If an error occurs during + * conversion, an error message is left in the interpreter's result + * unless "interp" is NULL. + * + * Side effects: + * If no error occurs, a regular expression is stored as "objPtr"s + * internal representation. + * + *---------------------------------------------------------------------- + */ + +static int +SetRegexpFromAny( + Tcl_Interp *interp, /* Used for error reporting if not NULL. */ + Tcl_Obj *objPtr) /* The object to convert. */ +{ + if (Tcl_GetRegExpFromObj(interp, objPtr, REG_ADVANCED) == NULL) { + return TCL_ERROR; + } + return TCL_OK; +} + +/* + *--------------------------------------------------------------------------- + * + * CompileRegexp -- + * + * Attempt to compile the given regexp pattern. If the compiled regular + * expression can be found in the per-thread cache, it will be used + * instead of compiling a new copy. + * + * Results: + * The return value is a pointer to a newly allocated TclRegexp that + * represents the compiled pattern, or NULL if the pattern could not be + * compiled. If NULL is returned, an error message is left in the + * interp's result. + * + * Side effects: + * The thread-local regexp cache is updated and a new TclRegexp may be + * allocated. + * + *---------------------------------------------------------------------- + */ + +static TclRegexp * +CompileRegexp( + Tcl_Interp *interp, /* Used for error reporting if not NULL. */ + const char *string, /* The regexp to compile (UTF-8). */ + int length, /* The length of the string in bytes. */ + int flags) /* Compilation flags. */ +{ + TclRegexp *regexpPtr; + const Tcl_UniChar *uniString; + int numChars, status, i, exact; + Tcl_DString stringBuf; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + if (!tsdPtr->initialized) { + tsdPtr->initialized = 1; + Tcl_CreateThreadExitHandler(FinalizeRegexp, NULL); + } + + /* + * This routine maintains a second-level regular expression cache in + * addition to the per-object regexp cache. The per-thread cache is needed + * to handle the case where for various reasons the object is lost between + * invocations of the regexp command, but the literal pattern is the same. + */ + + /* + * Check the per-thread compiled regexp cache. We can only reuse a regexp + * if it has the same pattern and the same flags. + */ + + for (i = 0; (i < NUM_REGEXPS) && (tsdPtr->patterns[i] != NULL); i++) { + if ((length == tsdPtr->patLengths[i]) + && (tsdPtr->regexps[i]->flags == flags) + && (strcmp(string, tsdPtr->patterns[i]) == 0)) { + /* + * Move the matched pattern to the first slot in the cache and + * shift the other patterns down one position. + */ + + if (i != 0) { + int j; + char *cachedString; + + cachedString = tsdPtr->patterns[i]; + regexpPtr = tsdPtr->regexps[i]; + for (j = i-1; j >= 0; j--) { + tsdPtr->patterns[j+1] = tsdPtr->patterns[j]; + tsdPtr->patLengths[j+1] = tsdPtr->patLengths[j]; + tsdPtr->regexps[j+1] = tsdPtr->regexps[j]; + } + tsdPtr->patterns[0] = cachedString; + tsdPtr->patLengths[0] = length; + tsdPtr->regexps[0] = regexpPtr; + } + return tsdPtr->regexps[0]; + } + } + + /* + * This is a new expression, so compile it and add it to the cache. + */ + + regexpPtr = ckalloc(sizeof(TclRegexp)); + regexpPtr->objPtr = NULL; + regexpPtr->string = NULL; + regexpPtr->details.rm_extend.rm_so = -1; + regexpPtr->details.rm_extend.rm_eo = -1; + + /* + * Get the up-to-date string representation and map to unicode. + */ + + Tcl_DStringInit(&stringBuf); + uniString = Tcl_UtfToUniCharDString(string, length, &stringBuf); + numChars = Tcl_DStringLength(&stringBuf) / sizeof(Tcl_UniChar); + + /* + * Compile the string and check for errors. + */ + + regexpPtr->flags = flags; + status = TclReComp(®expPtr->re, uniString, (size_t) numChars, flags); + Tcl_DStringFree(&stringBuf); + + if (status != REG_OKAY) { + /* + * Clean up and report errors in the interpreter, if possible. + */ + + ckfree(regexpPtr); + if (interp) { + TclRegError(interp, + "couldn't compile regular expression pattern: ", status); + } + return NULL; + } + + /* + * Convert RE to a glob pattern equivalent, if any, and cache it. If this + * is not possible, then globObjPtr will be NULL. This is used by + * Tcl_RegExpExecObj to optionally do a fast match (avoids RE engine). + */ + + if (TclReToGlob(NULL, string, length, &stringBuf, &exact) == TCL_OK) { + regexpPtr->globObjPtr = TclDStringToObj(&stringBuf); + Tcl_IncrRefCount(regexpPtr->globObjPtr); + } else { + regexpPtr->globObjPtr = NULL; + } + + /* + * Allocate enough space for all of the subexpressions, plus one extra for + * the entire pattern. + */ + + regexpPtr->matches = + ckalloc(sizeof(regmatch_t) * (regexpPtr->re.re_nsub + 1)); + + /* + * Initialize the refcount to one initially, since it is in the cache. + */ + + regexpPtr->refCount = 1; + + /* + * Free the last regexp, if necessary, and make room at the head of the + * list for the new regexp. + */ + + if (tsdPtr->patterns[NUM_REGEXPS-1] != NULL) { + TclRegexp *oldRegexpPtr = tsdPtr->regexps[NUM_REGEXPS-1]; + + if (--(oldRegexpPtr->refCount) <= 0) { + FreeRegexp(oldRegexpPtr); + } + ckfree(tsdPtr->patterns[NUM_REGEXPS-1]); + } + for (i = NUM_REGEXPS - 2; i >= 0; i--) { + tsdPtr->patterns[i+1] = tsdPtr->patterns[i]; + tsdPtr->patLengths[i+1] = tsdPtr->patLengths[i]; + tsdPtr->regexps[i+1] = tsdPtr->regexps[i]; + } + tsdPtr->patterns[0] = ckalloc(length + 1); + memcpy(tsdPtr->patterns[0], string, (unsigned) length + 1); + tsdPtr->patLengths[0] = length; + tsdPtr->regexps[0] = regexpPtr; + + return regexpPtr; +} + +/* + *---------------------------------------------------------------------- + * + * FreeRegexp -- + * + * Release the storage associated with a TclRegexp. + * + * Results: + * None. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static void +FreeRegexp( + TclRegexp *regexpPtr) /* Compiled regular expression to free. */ +{ + TclReFree(®expPtr->re); + if (regexpPtr->globObjPtr) { + TclDecrRefCount(regexpPtr->globObjPtr); + } + if (regexpPtr->matches) { + ckfree(regexpPtr->matches); + } + ckfree(regexpPtr); +} + +/* + *---------------------------------------------------------------------- + * + * FinalizeRegexp -- + * + * Release the storage associated with the per-thread regexp cache. + * + * Results: + * None. + * + * Side effects: + * None. + * + *---------------------------------------------------------------------- + */ + +static void +FinalizeRegexp( + ClientData clientData) /* Not used. */ +{ + int i; + TclRegexp *regexpPtr; + ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey); + + for (i = 0; (i < NUM_REGEXPS) && (tsdPtr->patterns[i] != NULL); i++) { + regexpPtr = tsdPtr->regexps[i]; + if (--(regexpPtr->refCount) <= 0) { + FreeRegexp(regexpPtr); + } + ckfree(tsdPtr->patterns[i]); + tsdPtr->patterns[i] = NULL; + } + + /* + * We may find ourselves reinitialized if another finalization routine + * invokes regexps. + */ + + tsdPtr->initialized = 0; +} + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |