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Diffstat (limited to 'generic/tclParseExpr.c')
| -rw-r--r-- | generic/tclParseExpr.c | 1080 |
1 files changed, 1080 insertions, 0 deletions
diff --git a/generic/tclParseExpr.c b/generic/tclParseExpr.c new file mode 100644 index 0000000..c6471a2 --- /dev/null +++ b/generic/tclParseExpr.c @@ -0,0 +1,1080 @@ +/* + * tclParseExpr.c -- + * + * This file contains functions that parse Tcl expressions. They do so in + * a general-purpose fashion that can be used for many different + * purposes, including compilation, direct execution, code analysis, etc. + * + * Copyright (c) 1997 Sun Microsystems, Inc. + * Copyright (c) 1998-2000 by Scriptics Corporation. + * Contributions from Don Porter, NIST, 2006. (not subject to US copyright) + * + * See the file "license.terms" for information on usage and redistribution of + * this file, and for a DISCLAIMER OF ALL WARRANTIES. + * + * RCS: @(#) $Id: tclParseExpr.c,v 1.44 2006/08/30 20:46:20 dgp Exp $ + */ + +#include "tclInt.h" + +/* + * The ExprNode structure represents one node of the parse tree produced + * as an interim structure by the expression parser. + */ + +typedef struct ExprNode { + unsigned char lexeme; /* Code that identifies the type of this node */ + int left; /* Index of the left operand of this operator node */ + int right; /* Index of the right operand of this operator node */ + int parent; /* Index of the operator of this operand node */ + int token; /* Index of the Tcl_Tokens of this leaf node */ +} ExprNode; + +/* + * Set of lexeme codes stored in ExprNode structs to label and categorize + * the lexemes found. + */ + +#define LEAF (1<<7) +#define UNARY (1<<6) +#define BINARY (1<<5) + +#define NODE_TYPE ( LEAF | UNARY | BINARY) + +#define PLUS 1 +#define MINUS 2 +#define BAREWORD 3 +#define INCOMPLETE 4 +#define INVALID 5 + +#define NUMBER ( LEAF | 1) +#define SCRIPT ( LEAF | 2) +#define BOOLEAN ( LEAF | BAREWORD) +#define BRACED ( LEAF | 4) +#define VARIABLE ( LEAF | 5) +#define QUOTED ( LEAF | 6) +#define EMPTY ( LEAF | 7) + +#define UNARY_PLUS ( UNARY | PLUS) +#define UNARY_MINUS ( UNARY | MINUS) +#define FUNCTION ( UNARY | BAREWORD) +#define START ( UNARY | 4) +#define OPEN_PAREN ( UNARY | 5) +#define NOT ( UNARY | 6) +#define BIT_NOT ( UNARY | 7) + +#define BINARY_PLUS ( BINARY | PLUS) +#define BINARY_MINUS ( BINARY | MINUS) +#define COMMA ( BINARY | 3) +#define MULT ( BINARY | 4) +#define DIVIDE ( BINARY | 5) +#define MOD ( BINARY | 6) +#define LESS ( BINARY | 7) +#define GREATER ( BINARY | 8) +#define BIT_AND ( BINARY | 9) +#define BIT_XOR ( BINARY | 10) +#define BIT_OR ( BINARY | 11) +#define QUESTION ( BINARY | 12) +#define COLON ( BINARY | 13) +#define LEFT_SHIFT ( BINARY | 14) +#define RIGHT_SHIFT ( BINARY | 15) +#define LEQ ( BINARY | 16) +#define GEQ ( BINARY | 17) +#define EQUAL ( BINARY | 18) +#define NEQ ( BINARY | 19) +#define AND ( BINARY | 20) +#define OR ( BINARY | 21) +#define STREQ ( BINARY | 22) +#define STRNEQ ( BINARY | 23) +#define EXPON ( BINARY | 24) +#define IN_LIST ( BINARY | 25) +#define NOT_IN_LIST ( BINARY | 26) +#define CLOSE_PAREN ( BINARY | 27) +#define END ( BINARY | 28) + +/* + * Declarations for local functions to this file: + */ + +static void GenerateTokens(ExprNode *nodes, Tcl_Parse *scratchPtr, + Tcl_Parse *parsePtr); +static int ParseLexeme(CONST char *start, int numBytes, + unsigned char *lexemePtr); + + +/* + *---------------------------------------------------------------------- + * + * Tcl_ParseExpr -- + * + * Given a string, the numBytes bytes starting at start, this function + * parses it as a Tcl expression and stores information about the + * structure of the expression in the Tcl_Parse struct indicated by the + * caller. + * + * Results: + * If the string is successfully parsed as a valid Tcl expression, + * TCL_OK is returned, and data about the expression structure is + * written to *parsePtr. If the string cannot be parsed as a valid + * Tcl expression, TCL_ERROR is returned, and if interp is non-NULL, + * an error message is written to interp. + * + * Side effects: + * If there is insufficient space in parsePtr to hold all the information + * about the expression, then additional space is malloc-ed. If the + * function returns TCL_OK then the caller must eventually invoke + * Tcl_FreeParse to release any additional space that was allocated. + * + *---------------------------------------------------------------------- + */ + +int +Tcl_ParseExpr( + Tcl_Interp *interp, /* Used for error reporting. */ + CONST char *start, /* Start of source string to parse. */ + int numBytes, /* Number of bytes in string. If < 0, the + * string consists of all bytes up to the + * first null character. */ + Tcl_Parse *parsePtr) /* Structure to fill with information about + * the parsed expression; any previous + * information in the structure is ignored. */ +{ +#define NUM_STATIC_NODES 64 + ExprNode staticNodes[NUM_STATIC_NODES]; + ExprNode *lastOrphanPtr, *nodes = staticNodes; + int nodesAvailable = NUM_STATIC_NODES; + int nodesUsed = 0; + Tcl_Parse scratch; /* Parsing scratch space */ + Tcl_Obj *msg = NULL, *post = NULL; + int scanned = 0, code = TCL_OK, insertMark = 0; + CONST char *mark = "_@_"; + CONST int limit = 25; + static CONST unsigned char prec[80] = { + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 15, 15, 5, 16, 16, 16, 13, 13, 11, 10, 9, 6, 6, 14, 14, + 13, 13, 12, 12, 8, 7, 12, 12, 17, 12, 12, 3, 1, 0, 0, 0, + 0, 18, 18, 18, 2, 4, 18, 18, 0, 0, 0, 0, 0, 0, 0, 0, + }; + + if (numBytes < 0) { + numBytes = (start ? strlen(start) : 0); + } + + TclParseInit(interp, start, numBytes, &scratch); + TclParseInit(interp, start, numBytes, parsePtr); + + /* Initialize the parse tree with the special "START" node */ + + nodes->lexeme = START; + nodes->left = -1; + nodes->right = -1; + nodes->parent = -1; + nodes->token = -1; + lastOrphanPtr = nodes; + nodesUsed++; + + while ((code == TCL_OK) && (lastOrphanPtr->lexeme != END)) { + ExprNode *nodePtr, *lastNodePtr; + Tcl_Token *tokenPtr; + + /* + * Each pass through this loop adds one more ExprNode. + * Allocate space for one if required. + */ + if (nodesUsed >= nodesAvailable) { + int lastOrphanIdx = lastOrphanPtr - nodes; + int size = nodesUsed * 2; + ExprNode *newPtr; + + if (nodes == staticNodes) { + nodes = NULL; + } + do { + newPtr = (ExprNode *) attemptckrealloc( (char *) nodes, + (unsigned int) (size * sizeof(ExprNode)) ); + } while ((newPtr == NULL) + && ((size -= (size - nodesUsed) / 2) > nodesUsed)); + if (newPtr == NULL) { + msg = Tcl_NewStringObj( + "not enough memory to parse expression", -1); + code = TCL_ERROR; + continue; + } + nodesAvailable = size; + if (nodes == NULL) { + memcpy((VOID *) newPtr, (VOID *) staticNodes, + (size_t) (nodesUsed * sizeof(ExprNode))); + } + nodes = newPtr; + lastOrphanPtr = nodes + lastOrphanIdx; + } + nodePtr = nodes + nodesUsed; + lastNodePtr = nodePtr - 1; + + /* Skip white space between lexemes */ + + scanned = TclParseAllWhiteSpace(start, numBytes); + start += scanned; + numBytes -= scanned; + + scanned = ParseLexeme(start, numBytes, &(nodePtr->lexeme)); + + /* Use context to categorize the lexemes that are ambiguous */ + + if ((NODE_TYPE & nodePtr->lexeme) == 0) { + switch (nodePtr->lexeme) { + case INVALID: + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, + "invalid character \"%.*s\"", scanned, start); + code = TCL_ERROR; + continue; + case INCOMPLETE: + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, + "incomplete operator \"%.*s\"", scanned, start); + code = TCL_ERROR; + continue; + case BAREWORD: + if (start[scanned+TclParseAllWhiteSpace( + start+scanned, numBytes-scanned)] == '(') { + nodePtr->lexeme = FUNCTION; + } else { + Tcl_Obj *objPtr = Tcl_NewStringObj(start, scanned); + Tcl_IncrRefCount(objPtr); + code = Tcl_ConvertToType(NULL, objPtr, &tclBooleanType); + Tcl_DecrRefCount(objPtr); + if (code == TCL_OK) { + nodePtr->lexeme = BOOLEAN; + } else { + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, "invalid bareword \"%.*s%s\"", + (scanned < limit) ? scanned : limit - 3, start, + (scanned < limit) ? "" : "..."); + post = Tcl_NewObj(); + TclObjPrintf(NULL, post, + "should be \"$%.*s%s\" or \"{%.*s%s}\"", + (scanned < limit) ? scanned : limit - 3, + start, (scanned < limit) ? "" : "...", + (scanned < limit) ? scanned : limit - 3, + start, (scanned < limit) ? "" : "..."); + TclObjPrintf(NULL, post, " or \"%.*s%s(...)\" or ...", + (scanned < limit) ? scanned : limit - 3, + start, (scanned < limit) ? "" : "..."); + continue; + } + } + break; + case PLUS: + case MINUS: + if ((NODE_TYPE & lastNodePtr->lexeme) == LEAF) { + nodePtr->lexeme |= BINARY; + } else { + nodePtr->lexeme |= UNARY; + } + } + } + + /* Add node to parse tree based on category */ + + switch (NODE_TYPE & nodePtr->lexeme) { + case LEAF: { + CONST char *end; + + if ((NODE_TYPE & lastNodePtr->lexeme) == LEAF) { + CONST char *operand = + scratch.tokenPtr[lastNodePtr->token].start; + + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, "missing operator at %s", mark); + if (operand[0] == '0') { + Tcl_Obj *copy = Tcl_NewStringObj(operand, + start + scanned - operand); + if (TclCheckBadOctal(NULL, Tcl_GetString(copy))) { + post = Tcl_NewStringObj( + "looks like invalid octal number", -1); + } + Tcl_DecrRefCount(copy); + } + scanned = 0; + insertMark = 1; + code = TCL_ERROR; + continue; + } + + if (scratch.numTokens+1 >= scratch.tokensAvailable) { + TclExpandTokenArray(&scratch); + } + nodePtr->token = scratch.numTokens; + tokenPtr = scratch.tokenPtr + nodePtr->token; + tokenPtr->type = TCL_TOKEN_SUB_EXPR; + tokenPtr->start = start; + scratch.numTokens++; + + switch (nodePtr->lexeme) { + case NUMBER: + case BOOLEAN: + tokenPtr = scratch.tokenPtr + scratch.numTokens; + tokenPtr->type = TCL_TOKEN_TEXT; + tokenPtr->start = start; + tokenPtr->size = scanned; + tokenPtr->numComponents = 0; + scratch.numTokens++; + + break; + + case QUOTED: + code = Tcl_ParseQuotedString(interp, start, numBytes, + &scratch, 1, &end); + if (code != TCL_OK) { + scanned = scratch.term - start; + scanned += (scanned < numBytes); + continue; + } + scanned = end - start; + break; + + case BRACED: + code = Tcl_ParseBraces(interp, start, numBytes, + &scratch, 1, &end); + if (code != TCL_OK) { + continue; + } + scanned = end - start; + break; + + case VARIABLE: + code = Tcl_ParseVarName(interp, start, numBytes, &scratch, 1); + if (code != TCL_OK) { + scanned = scratch.term - start; + scanned += (scanned < numBytes); + continue; + } + tokenPtr = scratch.tokenPtr + nodePtr->token + 1; + if (tokenPtr->type != TCL_TOKEN_VARIABLE) { + msg = Tcl_NewStringObj("invalid character \"$\"", -1); + code = TCL_ERROR; + continue; + } + scanned = tokenPtr->size; + break; + + case SCRIPT: + tokenPtr = scratch.tokenPtr + scratch.numTokens; + tokenPtr->type = TCL_TOKEN_COMMAND; + tokenPtr->start = start; + tokenPtr->numComponents = 0; + + end = start + numBytes; + start++; + while (1) { + Tcl_Parse nested; + code = Tcl_ParseCommand(interp, + start, (end - start), 1, &nested); + if (code != TCL_OK) { + parsePtr->term = nested.term; + parsePtr->errorType = nested.errorType; + parsePtr->incomplete = nested.incomplete; + break; + } + start = (nested.commandStart + nested.commandSize); + Tcl_FreeParse(&nested); + if ((nested.term < end) && (*nested.term == ']') + && !nested.incomplete) { + break; + } + + if (start == end) { + msg = Tcl_NewStringObj("missing close-bracket", -1); + parsePtr->term = tokenPtr->start; + parsePtr->errorType = TCL_PARSE_MISSING_BRACKET; + parsePtr->incomplete = 1; + code = TCL_ERROR; + break; + } + } + end = start; + start = tokenPtr->start; + if (code != TCL_OK) { + scanned = parsePtr->term - start; + scanned += (scanned < numBytes); + continue; + } + scanned = end - start; + tokenPtr->size = scanned; + scratch.numTokens++; + break; + } + + tokenPtr = scratch.tokenPtr + nodePtr->token; + tokenPtr->size = scanned; + tokenPtr->numComponents = scratch.numTokens - nodePtr->token - 1; + + nodePtr->left = -1; + nodePtr->right = -1; + nodePtr->parent = -1; + lastOrphanPtr = nodePtr; + nodesUsed++; + break; + } + + case UNARY: + if ((NODE_TYPE & lastNodePtr->lexeme) == LEAF) { + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, "missing operator at %s", mark); + scanned = 0; + insertMark = 1; + code = TCL_ERROR; + continue; + } + nodePtr->left = -1; + nodePtr->right = -1; + nodePtr->parent = -1; + + if (scratch.numTokens >= scratch.tokensAvailable) { + TclExpandTokenArray(&scratch); + } + nodePtr->token = scratch.numTokens; + tokenPtr = scratch.tokenPtr + nodePtr->token; + tokenPtr->type = TCL_TOKEN_OPERATOR; + tokenPtr->start = start; + tokenPtr->size = scanned; + tokenPtr->numComponents = 0; + scratch.numTokens++; + + lastOrphanPtr = nodePtr; + nodesUsed++; + break; + + case BINARY: { + ExprNode *otherPtr = NULL; + unsigned char precedence = prec[nodePtr->lexeme]; + + if ((nodePtr->lexeme == CLOSE_PAREN) + && (lastNodePtr->lexeme == OPEN_PAREN)) { + if (lastNodePtr[-1].lexeme == FUNCTION) { + /* Normally, "()" is a syntax error, but as a special + * case accept it as an argument list for a function */ + scanned = 0; + nodePtr->lexeme = EMPTY; + nodePtr->left = -1; + nodePtr->right = -1; + nodePtr->parent = -1; + nodePtr->token = -1; + + lastOrphanPtr = nodePtr; + nodesUsed++; + break; + + } + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, "empty subexpression at %s", mark); + scanned = 0; + insertMark = 1; + code = TCL_ERROR; + continue; + } + + + if ((NODE_TYPE & lastNodePtr->lexeme) != LEAF) { + if (prec[lastNodePtr->lexeme] > precedence) { + if (lastNodePtr->lexeme == OPEN_PAREN) { + msg = Tcl_NewStringObj("unbalanced open paren", -1); + } else if (lastNodePtr->lexeme == COMMA) { + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, + "missing function argument at %s", mark); + scanned = 0; + insertMark = 1; + } else if (lastNodePtr->lexeme == START) { + msg = Tcl_NewStringObj("empty expression", -1); + } + } else { + if (nodePtr->lexeme == CLOSE_PAREN) { + msg = Tcl_NewStringObj("unbalanced close paren", -1); + } else if ((nodePtr->lexeme == COMMA) + && (lastNodePtr->lexeme == OPEN_PAREN) + && (lastNodePtr[-1].lexeme == FUNCTION)) { + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, + "missing function argument at %s", mark); + scanned = 0; + insertMark = 1; + } + } + if (msg == NULL) { + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, "missing operand at %s", mark); + scanned = 0; + insertMark = 1; + } + code = TCL_ERROR; + continue; + } + + while (1) { + + if (lastOrphanPtr->parent >= 0) { + otherPtr = nodes + lastOrphanPtr->parent; + } else if (lastOrphanPtr->left >= 0) { + Tcl_Panic("Tcl_ParseExpr: left closure programming error"); + } else { + lastOrphanPtr->parent = lastOrphanPtr - nodes; + otherPtr = lastOrphanPtr; + } + otherPtr--; + + if (prec[otherPtr->lexeme] < precedence) { + break; + } + + /* Special association rules for the ternary operators */ + if (prec[otherPtr->lexeme] == precedence) { + if ((otherPtr->lexeme == QUESTION) + && (lastOrphanPtr->lexeme != COLON)) { + break; + } + if ((otherPtr->lexeme == COLON) + && (nodePtr->lexeme == QUESTION)) { + break; + } + } + + /* Some checks before linking */ + if ((otherPtr->lexeme == OPEN_PAREN) + && (nodePtr->lexeme != CLOSE_PAREN)) { + lastOrphanPtr = otherPtr; + msg = Tcl_NewStringObj("unbalanced open paren", -1); + code = TCL_ERROR; + break; + } + if ((otherPtr->lexeme == QUESTION) + && (lastOrphanPtr->lexeme != COLON)) { + msg = Tcl_NewObj(); + TclObjPrintf(NULL, msg, + "missing operator \":\" at %s", mark); + scanned = 0; + insertMark = 1; + code = TCL_ERROR; + break; + } + if ((lastOrphanPtr->lexeme == COLON) + && (otherPtr->lexeme != QUESTION)) { + msg = Tcl_NewStringObj( + "unexpected operator \":\" without preceding \"?\"", + -1); + code = TCL_ERROR; + break; + } + + /* Link orphan as right operand of otherPtr */ + otherPtr->right = lastOrphanPtr - nodes; + lastOrphanPtr->parent = otherPtr - nodes; + lastOrphanPtr = otherPtr; + + if (otherPtr->lexeme == OPEN_PAREN) { + /* CLOSE_PAREN can only close one OPEN_PAREN */ + tokenPtr = scratch.tokenPtr + otherPtr->token; + tokenPtr->size = start + scanned - tokenPtr->start; + break; + } + if (otherPtr->lexeme == START) { + /* Don't backtrack beyond the start */ + break; + } + } + if (code != TCL_OK) { + continue; + } + + if (nodePtr->lexeme == CLOSE_PAREN) { + if (otherPtr->lexeme == START) { + msg = Tcl_NewStringObj("unbalanced close paren", -1); + code = TCL_ERROR; + continue; + } + /* Create no node for a CLOSE_PAREN lexeme */ + break; + } + + if ((nodePtr->lexeme == COMMA) && ((otherPtr->lexeme != OPEN_PAREN) + || (otherPtr[-1].lexeme != FUNCTION))) { + msg = Tcl_NewStringObj( + "unexpected \",\" outside function argument list", -1); + code = TCL_ERROR; + continue; + } + + if (lastOrphanPtr->lexeme == COLON) { + msg = Tcl_NewStringObj( + "unexpected operator \":\" without preceding \"?\"", + -1); + code = TCL_ERROR; + continue; + } + + /* Link orphan as left operand of new node */ + nodePtr->right = -1; + + if (scratch.numTokens >= scratch.tokensAvailable) { + TclExpandTokenArray(&scratch); + } + nodePtr->token = scratch.numTokens; + tokenPtr = scratch.tokenPtr + nodePtr->token; + tokenPtr->type = TCL_TOKEN_OPERATOR; + tokenPtr->start = start; + tokenPtr->size = scanned; + tokenPtr->numComponents = 0; + scratch.numTokens++; + + nodePtr->left = lastOrphanPtr - nodes; + nodePtr->parent = lastOrphanPtr->parent; + lastOrphanPtr->parent = nodePtr - nodes; + lastOrphanPtr = nodePtr; + nodesUsed++; + break; + } + } + + start += scanned; + numBytes -= scanned; + } + + if (code == TCL_OK) { + /* Shift tokens from scratch space to caller space */ + GenerateTokens(nodes, &scratch, parsePtr); + } else { + if (parsePtr->errorType == TCL_PARSE_SUCCESS) { + parsePtr->errorType = TCL_PARSE_SYNTAX; + parsePtr->term = start; + } + if (interp == NULL) { + if (msg) { + Tcl_DecrRefCount(msg); + } + } else { + if (msg == NULL) { + msg = Tcl_GetObjResult(interp); + } + TclObjPrintf(NULL, msg, "\nin expression \"%s%.*s%.*s%s%s%.*s%s\"", + ((start - limit) < scratch.string) ? "" : "...", + ((start - limit) < scratch.string) + ? (start - scratch.string) : limit - 3, + ((start - limit) < scratch.string) + ? scratch.string : start - limit + 3, + (scanned < limit) ? scanned : limit - 3, start, + (scanned < limit) ? "" : "...", + insertMark ? mark : "", + (start + scanned + limit > scratch.end) + ? scratch.end - (start + scanned) : limit-3, + start + scanned, + (start + scanned + limit > scratch.end) ? "" : "..." + ); + if (post != NULL) { + Tcl_AppendToObj(msg, ";\n", -1); + Tcl_AppendObjToObj(msg, post); + Tcl_DecrRefCount(post); + } + Tcl_SetObjResult(interp, msg); + numBytes = scratch.end - scratch.string; + TclFormatToErrorInfo(interp, + "\n (parsing expression \"%.*s%s\")", + (numBytes < limit) ? numBytes : limit - 3, + scratch.string, (numBytes < limit) ? "" : "..."); + } + } + + if (nodes != staticNodes) { + ckfree((char *)nodes); + } + Tcl_FreeParse(&scratch); + return code; +} + +/* + *---------------------------------------------------------------------- + * + * GenerateTokens -- + * + * Routine that generates Tcl_Tokens that represent a Tcl expression + * and writes them to *parsePtr. The parse tree of the expression + * is in the array of ExprNodes, nodes. Some of the Tcl_Tokens are + * copied from scratch space at *scratchPtr, where the parsing pass + * that constructed the parse tree left them. + * + *---------------------------------------------------------------------- + */ + +static void +GenerateTokens( + ExprNode *nodes, + Tcl_Parse *scratchPtr, + Tcl_Parse *parsePtr) +{ + ExprNode *nodePtr = nodes + nodes->right; + Tcl_Token *sourcePtr, *destPtr, *tokenPtr = scratchPtr->tokenPtr; + int toCopy; + CONST char *end = tokenPtr->start + tokenPtr->size; + + while (nodePtr->lexeme != START) { + switch (NODE_TYPE & nodePtr->lexeme) { + case BINARY: + if (nodePtr->left >= 0) { + if ((nodePtr->lexeme != COMMA) && (nodePtr->lexeme != COLON)) { + sourcePtr = scratchPtr->tokenPtr + nodePtr->token; + if (parsePtr->numTokens + 1 >= parsePtr->tokensAvailable) { + TclExpandTokenArray(parsePtr); + } + destPtr = parsePtr->tokenPtr + parsePtr->numTokens; + nodePtr->token = parsePtr->numTokens; + destPtr->type = TCL_TOKEN_SUB_EXPR; + destPtr->start = tokenPtr->start; + destPtr++; + *destPtr = *sourcePtr; + parsePtr->numTokens += 2; + } + nodePtr = nodes + nodePtr->left; + nodes[nodePtr->parent].left = -1; + } else if (nodePtr->right >= 0) { + tokenPtr += tokenPtr->numComponents + 1; + nodePtr = nodes + nodePtr->right; + nodes[nodePtr->parent].right = -1; + } else { + if ((nodePtr->lexeme != COMMA) && (nodePtr->lexeme != COLON)) { + destPtr = parsePtr->tokenPtr + nodePtr->token; + destPtr->size = end - destPtr->start; + destPtr->numComponents = + parsePtr->numTokens - nodePtr->token - 1; + } + nodePtr = nodes + nodePtr->parent; + } + break; + + case UNARY: + if (nodePtr->right >= 0) { + sourcePtr = scratchPtr->tokenPtr + nodePtr->token; + if (nodePtr->lexeme != OPEN_PAREN) { + if (parsePtr->numTokens + 1 >= parsePtr->tokensAvailable) { + TclExpandTokenArray(parsePtr); + } + destPtr = parsePtr->tokenPtr + parsePtr->numTokens; + nodePtr->token = parsePtr->numTokens; + destPtr->type = TCL_TOKEN_SUB_EXPR; + destPtr->start = tokenPtr->start; + destPtr++; + *destPtr = *sourcePtr; + parsePtr->numTokens += 2; + } + if (tokenPtr == sourcePtr) { + tokenPtr += tokenPtr->numComponents + 1; + } + nodePtr = nodes + nodePtr->right; + nodes[nodePtr->parent].right = -1; + } else { + if (nodePtr->lexeme != OPEN_PAREN) { + destPtr = parsePtr->tokenPtr + nodePtr->token; + destPtr->size = end - destPtr->start; + destPtr->numComponents = + parsePtr->numTokens - nodePtr->token - 1; + } else { + sourcePtr = scratchPtr->tokenPtr + nodePtr->token; + end = sourcePtr->start + sourcePtr->size; + } + nodePtr = nodes + nodePtr->parent; + } + break; + + case LEAF: + switch (nodePtr->lexeme) { + case EMPTY: + break; + + case BRACED: + case QUOTED: + sourcePtr = scratchPtr->tokenPtr + nodePtr->token; + end = sourcePtr->start + sourcePtr->size; + if (sourcePtr->numComponents > 1) { + toCopy = sourcePtr->numComponents; + if (tokenPtr == sourcePtr) { + tokenPtr += toCopy + 1; + } + sourcePtr->numComponents++; + while (parsePtr->numTokens + toCopy + 1 + >= parsePtr->tokensAvailable) { + TclExpandTokenArray(parsePtr); + } + destPtr = parsePtr->tokenPtr + parsePtr->numTokens; + *destPtr++ = *sourcePtr; + *destPtr = *sourcePtr++; + destPtr->type = TCL_TOKEN_WORD; + destPtr->numComponents = toCopy; + destPtr++; + memcpy((VOID *) destPtr, (VOID *) sourcePtr, + (size_t) (toCopy * sizeof(Tcl_Token))); + parsePtr->numTokens += toCopy + 2; + break; + } + + default: + sourcePtr = scratchPtr->tokenPtr + nodePtr->token; + end = sourcePtr->start + sourcePtr->size; + toCopy = sourcePtr->numComponents + 1; + if (tokenPtr == sourcePtr) { + tokenPtr += toCopy; + } + while (parsePtr->numTokens + toCopy - 1 + >= parsePtr->tokensAvailable) { + TclExpandTokenArray(parsePtr); + } + destPtr = parsePtr->tokenPtr + parsePtr->numTokens; + memcpy((VOID *) destPtr, (VOID *) sourcePtr, + (size_t) (toCopy * sizeof(Tcl_Token))); + parsePtr->numTokens += toCopy; + break; + + } + nodePtr = nodes + nodePtr->parent; + break; + + } + } +} + +/* + *---------------------------------------------------------------------- + * + * ParseLexeme -- + * + * Parse a single lexeme from the start of a string, scanning no + * more than numBytes bytes. + * + * Results: + * Returns the number of bytes scanned to produce the lexeme. + * + * Side effects: + * Code identifying lexeme parsed is writen to *lexemePtr. + * + *---------------------------------------------------------------------- + */ + +static int +ParseLexeme( + CONST char *start, /* Start of lexeme to parse. */ + int numBytes, /* Number of bytes in string. */ + unsigned char *lexemePtr) /* Write code of parsed lexeme to this + * storage. */ +{ + CONST char *end; + int scanned; + Tcl_UniChar ch; + + if (numBytes == 0) { + *lexemePtr = END; + return 0; + } + switch (*start) { + case '[': + *lexemePtr = SCRIPT; + return 1; + + case '{': + *lexemePtr = BRACED; + return 1; + + case '(': + *lexemePtr = OPEN_PAREN; + return 1; + + case ')': + *lexemePtr = CLOSE_PAREN; + return 1; + + case '$': + *lexemePtr = VARIABLE; + return 1; + + case '\"': + *lexemePtr = QUOTED; + return 1; + + case ',': + *lexemePtr = COMMA; + return 1; + + case '/': + *lexemePtr = DIVIDE; + return 1; + + case '%': + *lexemePtr = MOD; + return 1; + + case '+': + *lexemePtr = PLUS; + return 1; + + case '-': + *lexemePtr = MINUS; + return 1; + + case '?': + *lexemePtr = QUESTION; + return 1; + + case ':': + *lexemePtr = COLON; + return 1; + + case '^': + *lexemePtr = BIT_XOR; + return 1; + + case '~': + *lexemePtr = BIT_NOT; + return 1; + + case '*': + if ((numBytes > 1) && (start[1] == '*')) { + *lexemePtr = EXPON; + return 2; + } + *lexemePtr = MULT; + return 1; + + case '=': + if ((numBytes > 1) && (start[1] == '=')) { + *lexemePtr = EQUAL; + return 2; + } + *lexemePtr = INCOMPLETE; + return 1; + + case '!': + if ((numBytes > 1) && (start[1] == '=')) { + *lexemePtr = NEQ; + return 2; + } + *lexemePtr = NOT; + return 1; + + case '&': + if ((numBytes > 1) && (start[1] == '&')) { + *lexemePtr = AND; + return 2; + } + *lexemePtr = BIT_AND; + return 1; + + case '|': + if ((numBytes > 1) && (start[1] == '|')) { + *lexemePtr = OR; + return 2; + } + *lexemePtr = BIT_OR; + return 1; + + case '<': + if (numBytes > 1) { + switch (start[1]) { + case '<': + *lexemePtr = LEFT_SHIFT; + return 2; + case '=': + *lexemePtr = LEQ; + return 2; + } + } + *lexemePtr = LESS; + return 1; + + case '>': + if (numBytes > 1) { + switch (start[1]) { + case '>': + *lexemePtr = RIGHT_SHIFT; + return 2; + case '=': + *lexemePtr = GEQ; + return 2; + } + } + *lexemePtr = GREATER; + return 1; + + case 'i': + if ((numBytes > 1) && (start[1] == 'n') + && ((numBytes == 2) || !isalpha(UCHAR(start[2])))) { + /* + * Must make this check so we can tell the difference between + * the "in" operator and the "int" function name and the + * "infinity" numeric value. + */ + *lexemePtr = IN_LIST; + return 2; + } + break; + + case 'e': + if ((numBytes > 1) && (start[1] == 'q') + && ((numBytes == 2) || !isalpha(UCHAR(start[2])))) { + *lexemePtr = STREQ; + return 2; + } + break; + + case 'n': + if ((numBytes > 1) && ((numBytes == 2) || !isalpha(UCHAR(start[2])))) { + switch (start[1]) { + case 'e': + *lexemePtr = STRNEQ; + return 2; + case 'i': + *lexemePtr = NOT_IN_LIST; + return 2; + } + } + } + + if (TclParseNumber(NULL, NULL, NULL, start, numBytes, &end, + TCL_PARSE_NO_WHITESPACE) == TCL_OK) { + *lexemePtr = NUMBER; + return (end-start); + } + + if (Tcl_UtfCharComplete(start, numBytes)) { + scanned = Tcl_UtfToUniChar(start, &ch); + } else { + char utfBytes[TCL_UTF_MAX]; + memcpy(utfBytes, start, (size_t) numBytes); + utfBytes[numBytes] = '\0'; + scanned = Tcl_UtfToUniChar(utfBytes, &ch); + } + if (!isalpha(UCHAR(ch))) { + *lexemePtr = INVALID; + return scanned; + } + end = start; + while (isalnum(UCHAR(ch)) || (UCHAR(ch) == '_')) { + end += scanned; + numBytes -= scanned; + if (Tcl_UtfCharComplete(end, numBytes)) { + scanned = Tcl_UtfToUniChar(end, &ch); + } else { + char utfBytes[TCL_UTF_MAX]; + memcpy(utfBytes, end, (size_t) numBytes); + utfBytes[numBytes] = '\0'; + scanned = Tcl_UtfToUniChar(utfBytes, &ch); + } + } + *lexemePtr = BAREWORD; + return (end-start); +} + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |