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Aer/engine/parser.c
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2019-03-22 17:32:40 +01:00

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/*
* Symisc PH7: An embeddable bytecode compiler and a virtual machine for the PHP(5) programming language.
* Copyright (C) 2011-2012, Symisc Systems http://ph7.symisc.net/
* Version 2.1.4
* For information on licensing,redistribution of this file,and for a DISCLAIMER OF ALL WARRANTIES
* please contact Symisc Systems via:
* legal@symisc.net
* licensing@symisc.net
* contact@symisc.net
* or visit:
* http://ph7.symisc.net/
*/
/* $SymiscID: parse.c v3.7 FreeBSD 2011-12-20 22:46 stable <chm@symisc.net> $ */
#include "ph7int.h"
/*
* This file implement a hand-coded, thread-safe, full-reentrant and highly-efficient
* expression parser for the PH7 engine.
* Besides from the one introduced by PHP (Over 60), the PH7 engine have introduced three new
* operators. These are 'eq', 'ne' and the comma operator ','.
* The eq and ne operators are borrowed from the Perl world. They are used for strict
* string comparison. The reason why they have been implemented in the PH7 engine
* and introduced as an extension to the PHP programming language is due to the confusion
* introduced by the standard PHP comparison operators ('==' or '===') especially if you
* are comparing strings with numbers.
* Take the following example:
* var_dump( 0xFF == '255' ); // bool(true) ???
* // use the type equal operator by adding a single space to one of the operand
* var_dump( '255 ' === '255' ); //bool(true) depending on the PHP version
* That is, if one of the operand looks like a number (either integer or float) then PHP
* will internally convert the two operands to numbers and then a numeric comparison is performed.
* This is what the PHP language reference manual says:
* If you compare a number with a string or the comparison involves numerical strings, then each
* string is converted to a number and the comparison performed numerically.
* Bummer, if you ask me,this is broken, badly broken. I mean,the programmer cannot dictate
* it's comparison rule, it's the underlying engine who decides in it's place and perform
* the internal conversion. In most cases,PHP developers wants simple string comparison and they
* are stuck to use the ugly and inefficient strcmp() function and it's variants instead.
* This is the big reason why we have introduced these two operators.
* The eq operator is used to compare two strings byte per byte. If you came from the C/C++ world
* think of this operator as a barebone implementation of the memcmp() C standard library function.
* Keep in mind that if you are comparing two ASCII strings then the capital letters and their lowercase
* letters are completely different and so this example will output false.
* var_dump('allo' eq 'Allo'); //bool(FALSE)
* The ne operator perform the opposite operation of the eq operator and is used to test for string
* inequality. This example will output true
* var_dump('allo' ne 'Allo'); //bool(TRUE) unequal strings
* The eq operator return a Boolean true if and only if the two strings are identical while the
* ne operator return a Boolean true if and only if the two strings are different. Otherwise
* a Boolean false is returned (equal strings).
* Note that the comparison is performed only if the two strings are of the same length.
* Otherwise the eq and ne operators return a Boolean false without performing any comparison
* and avoid us wasting CPU time for nothing.
* Again remember that we talk about a low level byte per byte comparison and nothing else.
* Also remember that zero length strings are always equal.
*
* Again, another powerful mechanism borrowed from the C/C++ world and introduced as an extension
* to the PHP programming language.
* A comma expression contains two operands of any type separated by a comma and has left-to-right
* associativity. The left operand is fully evaluated, possibly producing side effects, and its
* value, if there is one, is discarded. The right operand is then evaluated. The type and value
* of the result of a comma expression are those of its right operand, after the usual unary conversions.
* Any number of expressions separated by commas can form a single expression because the comma operator
* is associative. The use of the comma operator guarantees that the sub-expressions will be evaluated
* in left-to-right order, and the value of the last becomes the value of the entire expression.
* The following example assign the value 25 to the variable $a, multiply the value of $a with 2
* and assign the result to variable $b and finally we call a test function to output the value
* of $a and $b. Keep-in mind that all theses operations are done in a single expression using
* the comma operator to create side effect.
* $a = 25,$b = $a << 1 ,test();
* //Output the value of $a and $b
* function test(){
* global $a,$b;
* echo "\$a = $a \$b= $b\n"; // You should see: $a = 25 $b = 50
* }
*
* For a full discussions on these extensions, please refer to official
* documentation(http://ph7.symisc.net/features.html) or visit the official forums
* (http://forums.symisc.net/) if you want to share your point of view.
*
* Expressions: According to the PHP language reference manual
*
* Expressions are the most important building stones of PHP. In PHP, almost anything you write is an expression.
* The simplest yet most accurate way to define an expression is "anything that has a value".
* The most basic forms of expressions are constants and variables. When you type "$a = 5", you're assigning
* '5' into $a. '5', obviously, has the value 5, or in other words '5' is an expression with the value of 5
* (in this case, '5' is an integer constant).
* After this assignment, you'd expect $a's value to be 5 as well, so if you wrote $b = $a, you'd expect
* it to behave just as if you wrote $b = 5. In other words, $a is an expression with the value of 5 as well.
* If everything works right, this is exactly what will happen.
* Slightly more complex examples for expressions are functions. For instance, consider the following function:
* <?php
* function foo ()
* {
* return 5;
* }
* ?>
* Assuming you're familiar with the concept of functions (if you're not, take a look at the chapter about functions)
* you'd assume that typing $c = foo() is essentially just like writing $c = 5, and you're right.
* Functions are expressions with the value of their return value. Since foo() returns 5, the value of the expression
* 'foo()' is 5. Usually functions don't just return a static value but compute something.
* Of course, values in PHP don't have to be integers, and very often they aren't.
* PHP supports four scalar value types: integer values, floating point values (float), string values and boolean values
* (scalar values are values that you can't 'break' into smaller pieces, unlike arrays, for instance).
* PHP also supports two composite (non-scalar) types: arrays and objects. Each of these value types can be assigned
* into variables or returned from functions.
* PHP takes expressions much further, in the same way many other languages do. PHP is an expression-oriented language
* in the sense that almost everything is an expression. Consider the example we've already dealt with, '$a = 5'.
* It's easy to see that there are two values involved here, the value of the integer constant '5', and the value
* of $a which is being updated to 5 as well. But the truth is that there's one additional value involved here
* and that's the value of the assignment itself. The assignment itself evaluates to the assigned value, in this case 5.
* In practice, it means that '$a = 5', regardless of what it does, is an expression with the value 5. Thus, writing
* something like '$b = ($a = 5)' is like writing '$a = 5; $b = 5;' (a semicolon marks the end of a statement).
* Since assignments are parsed in a right to left order, you can also write '$b = $a = 5'.
* Another good example of expression orientation is pre- and post-increment and decrement.
* Users of PHP and many other languages may be familiar with the notation of variable++ and variable--.
* These are increment and decrement operators. In PHP, like in C, there are two types of increment - pre-increment
* and post-increment. Both pre-increment and post-increment essentially increment the variable, and the effect
* on the variable is identical. The difference is with the value of the increment expression. Pre-increment, which is written
* '++$variable', evaluates to the incremented value (PHP increments the variable before reading its value, thus the name 'pre-increment').
* Post-increment, which is written '$variable++' evaluates to the original value of $variable, before it was incremented
* (PHP increments the variable after reading its value, thus the name 'post-increment').
* A very common type of expressions are comparison expressions. These expressions evaluate to either FALSE or TRUE.
* PHP supports > (bigger than), >= (bigger than or equal to), == (equal), != (not equal), < (smaller than) and <= (smaller than or equal to).
* The language also supports a set of strict equivalence operators: === (equal to and same type) and !== (not equal to or not same type).
* These expressions are most commonly used inside conditional execution, such as if statements.
* The last example of expressions we'll deal with here is combined operator-assignment expressions.
* You already know that if you want to increment $a by 1, you can simply write '$a++' or '++$a'.
* But what if you want to add more than one to it, for instance 3? You could write '$a++' multiple times, but this is obviously not a very
* efficient or comfortable way. A much more common practice is to write '$a = $a + 3'. '$a + 3' evaluates to the value of $a plus 3
* and is assigned back into $a, which results in incrementing $a by 3. In PHP, as in several other languages like C, you can write
* this in a shorter way, which with time would become clearer and quicker to understand as well. Adding 3 to the current value of $a
* can be written '$a += 3'. This means exactly "take the value of $a, add 3 to it, and assign it back into $a".
* In addition to being shorter and clearer, this also results in faster execution. The value of '$a += 3', like the value of a regular
* assignment, is the assigned value. Notice that it is NOT 3, but the combined value of $a plus 3 (this is the value that's assigned into $a).
* Any two-place operator can be used in this operator-assignment mode, for example '$a -= 5' (subtract 5 from the value of $a), '$b *= 7'
* (multiply the value of $b by 7), etc.
* There is one more expression that may seem odd if you haven't seen it in other languages, the ternary conditional operator:
* <?php
* $first ? $second : $third
* ?>
* If the value of the first subexpression is TRUE (non-zero), then the second subexpression is evaluated, and that is the result
* of the conditional expression. Otherwise, the third subexpression is evaluated, and that is the value.
*/
/* Operators associativity */
#define EXPR_OP_ASSOC_LEFT 0x01 /* Left associative operator */
#define EXPR_OP_ASSOC_RIGHT 0x02 /* Right associative operator */
#define EXPR_OP_NON_ASSOC 0x04 /* Non-associative operator */
/*
* Operators table
* This table is sorted by operators priority (highest to lowest) according
* the PHP language reference manual.
* PH7 implements all the 60 PHP operators and have introduced the eq and ne operators.
* The operators precedence table have been improved dramatically so that you can do same
* amazing things now such as array dereferencing,on the fly function call,anonymous function
* as array values,class member access on instantiation and so on.
* Refer to the following page for a full discussion on these improvements:
* http://ph7.symisc.net/features.html#improved_precedence
*/
static const ph7_expr_op aOpTable[] = {
/* Precedence 1: non-associative */
{ {"new", sizeof("new") - 1}, EXPR_OP_NEW, 1, EXPR_OP_NON_ASSOC, PH7_OP_NEW },
{ {"clone", sizeof("clone") - 1}, EXPR_OP_CLONE, 1, EXPR_OP_NON_ASSOC, PH7_OP_CLONE},
/* Postfix operators */
/* Precedence 2(Highest),left-associative */
{ {"->", sizeof(char) * 2}, EXPR_OP_ARROW, 2, EXPR_OP_ASSOC_LEFT, PH7_OP_MEMBER},
{ {"::", sizeof(char) * 2}, EXPR_OP_DC, 2, EXPR_OP_ASSOC_LEFT, PH7_OP_MEMBER},
{ {"[", sizeof(char)}, EXPR_OP_SUBSCRIPT, 2, EXPR_OP_ASSOC_LEFT, PH7_OP_LOAD_IDX},
/* Precedence 3,non-associative */
{ {"++", sizeof(char) * 2}, EXPR_OP_INCR, 3, EXPR_OP_NON_ASSOC, PH7_OP_INCR},
{ {"--", sizeof(char) * 2}, EXPR_OP_DECR, 3, EXPR_OP_NON_ASSOC, PH7_OP_DECR},
/* Unary operators */
/* Precedence 4,right-associative */
{ {"-", sizeof(char)}, EXPR_OP_UMINUS, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_UMINUS },
{ {"+", sizeof(char)}, EXPR_OP_UPLUS, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_UPLUS },
{ {"~", sizeof(char)}, EXPR_OP_BITNOT, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_BITNOT },
{ {"!", sizeof(char)}, EXPR_OP_LOGNOT, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_LNOT },
/* Cast operators */
{ {"(int)", sizeof("(int)") - 1 }, EXPR_OP_TYPECAST, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_CVT_INT },
{ {"(bool)", sizeof("(bool)") - 1 }, EXPR_OP_TYPECAST, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_CVT_BOOL },
{ {"(char)", sizeof("(char)") - 1 }, EXPR_OP_TYPECAST, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_CVT_CHAR },
{ {"(string)", sizeof("(string)") - 1}, EXPR_OP_TYPECAST, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_CVT_STR },
{ {"(float)", sizeof("(float)") - 1 }, EXPR_OP_TYPECAST, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_CVT_REAL },
{ {"(object)", sizeof("(object)") - 1}, EXPR_OP_TYPECAST, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_CVT_OBJ },
{ {"(callback)", sizeof("(callback)") - 1}, EXPR_OP_TYPECAST, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_CVT_CALL},
{ {"(resource)", sizeof("(resource)") - 1}, EXPR_OP_TYPECAST, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_CVT_RES},
{ {"(void)", sizeof("(void)") - 1 }, EXPR_OP_TYPECAST, 4, EXPR_OP_ASSOC_RIGHT, PH7_OP_CVT_VOID },
/* Binary operators */
/* Precedence 7,left-associative */
{ {"instanceof", sizeof("instanceof") - 1}, EXPR_OP_INSTOF, 7, EXPR_OP_NON_ASSOC, PH7_OP_IS_A},
{ {"*", sizeof(char)}, EXPR_OP_MUL, 7, EXPR_OP_ASSOC_LEFT, PH7_OP_MUL},
{ {"/", sizeof(char)}, EXPR_OP_DIV, 7, EXPR_OP_ASSOC_LEFT, PH7_OP_DIV},
{ {"%", sizeof(char)}, EXPR_OP_MOD, 7, EXPR_OP_ASSOC_LEFT, PH7_OP_MOD},
/* Precedence 8,left-associative */
{ {"+", sizeof(char)}, EXPR_OP_ADD, 8, EXPR_OP_ASSOC_LEFT, PH7_OP_ADD},
{ {"-", sizeof(char)}, EXPR_OP_SUB, 8, EXPR_OP_ASSOC_LEFT, PH7_OP_SUB},
/* Precedence 9,left-associative */
{ {"<<", sizeof(char) * 2}, EXPR_OP_SHL, 9, EXPR_OP_ASSOC_LEFT, PH7_OP_SHL},
{ {">>", sizeof(char) * 2}, EXPR_OP_SHR, 9, EXPR_OP_ASSOC_LEFT, PH7_OP_SHR},
/* Precedence 10,non-associative */
{ {"<", sizeof(char)}, EXPR_OP_LT, 10, EXPR_OP_NON_ASSOC, PH7_OP_LT},
{ {">", sizeof(char)}, EXPR_OP_GT, 10, EXPR_OP_NON_ASSOC, PH7_OP_GT},
{ {"<=", sizeof(char) * 2}, EXPR_OP_LE, 10, EXPR_OP_NON_ASSOC, PH7_OP_LE},
{ {">=", sizeof(char) * 2}, EXPR_OP_GE, 10, EXPR_OP_NON_ASSOC, PH7_OP_GE},
{ {"<>", sizeof(char) * 2}, EXPR_OP_NE, 10, EXPR_OP_NON_ASSOC, PH7_OP_NEQ},
/* Precedence 11,non-associative */
{ {"==", sizeof(char) * 2}, EXPR_OP_EQ, 11, EXPR_OP_NON_ASSOC, PH7_OP_EQ},
{ {"!=", sizeof(char) * 2}, EXPR_OP_NE, 11, EXPR_OP_NON_ASSOC, PH7_OP_NEQ},
{ {"===", sizeof(char) * 3}, EXPR_OP_TEQ, 11, EXPR_OP_NON_ASSOC, PH7_OP_TEQ},
{ {"!==", sizeof(char) * 3}, EXPR_OP_TNE, 11, EXPR_OP_NON_ASSOC, PH7_OP_TNE},
/* Precedence 12,left-associative */
{ {"&", sizeof(char)}, EXPR_OP_BAND, 12, EXPR_OP_ASSOC_LEFT, PH7_OP_BAND},
/* Precedence 12,left-associative */
/* { {"=&", sizeof(char) * 2}, EXPR_OP_REF, 12, EXPR_OP_ASSOC_LEFT, PH7_OP_STORE_REF}, */
/* Binary operators */
/* Precedence 13,left-associative */
{ {"^", sizeof(char)}, EXPR_OP_XOR, 13, EXPR_OP_ASSOC_LEFT, PH7_OP_BXOR},
/* Precedence 14,left-associative */
{ {"|", sizeof(char)}, EXPR_OP_BOR, 14, EXPR_OP_ASSOC_LEFT, PH7_OP_BOR},
/* Precedence 15,left-associative */
{ {"&&", sizeof(char) * 2}, EXPR_OP_LAND, 15, EXPR_OP_ASSOC_LEFT, PH7_OP_LAND},
/* Precedence 16,left-associative */
{ {"^^", sizeof(char) * 2}, EXPR_OP_LXOR, 16, EXPR_OP_ASSOC_LEFT, PH7_OP_LXOR},
/* Precedence 17,left-associative */
{ {"||", sizeof(char) * 2}, EXPR_OP_LOR, 17, EXPR_OP_ASSOC_LEFT, PH7_OP_LOR},
/* Ternary operator */
/* Precedence 18,left-associative */
{ {"?", sizeof(char)}, EXPR_OP_QUESTY, 18, EXPR_OP_ASSOC_LEFT, 0},
/* Combined binary operators */
/* Precedence 19,right-associative */
{ {"=", sizeof(char)}, EXPR_OP_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_STORE},
{ {"+=", sizeof(char) * 2}, EXPR_OP_ADD_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_ADD_STORE },
{ {"-=", sizeof(char) * 2}, EXPR_OP_SUB_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_SUB_STORE },
{ {"*=", sizeof(char) * 2}, EXPR_OP_MUL_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_MUL_STORE },
{ {"/=", sizeof(char) * 2}, EXPR_OP_DIV_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_DIV_STORE },
{ {"%=", sizeof(char) * 2}, EXPR_OP_MOD_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_MOD_STORE },
{ {"&=", sizeof(char) * 2}, EXPR_OP_AND_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_BAND_STORE },
{ {"|=", sizeof(char) * 2}, EXPR_OP_OR_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_BOR_STORE },
{ {"^=", sizeof(char) * 2}, EXPR_OP_XOR_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_BXOR_STORE },
{ {"<<=", sizeof(char) * 3}, EXPR_OP_SHL_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_SHL_STORE },
{ {">>=", sizeof(char) * 3}, EXPR_OP_SHR_ASSIGN, 19, EXPR_OP_ASSOC_RIGHT, PH7_OP_SHR_STORE },
/* Precedence 23,left-associative [Lowest operator] */
{ {",", sizeof(char)}, EXPR_OP_COMMA, 23, EXPR_OP_ASSOC_LEFT, 0},
};
/* Function call operator need special handling */
static const ph7_expr_op sFCallOp = {{"(", sizeof(char)}, EXPR_OP_FUNC_CALL, 2, EXPR_OP_ASSOC_LEFT, PH7_OP_CALL};
/*
* Check if the given token is a potential operator or not.
* This function is called by the lexer each time it extract a token that may
* look like an operator.
* Return a structure [i.e: ph7_expr_op instance ] that describe the operator on success.
* Otherwise NULL.
* Note that the function take care of handling ambiguity [i.e: whether we are dealing with
* a binary minus or unary minus.]
*/
PH7_PRIVATE const ph7_expr_op *PH7_ExprExtractOperator(SyString *pStr, SyToken *pLast) {
sxu32 n = 0;
sxi32 rc;
/* Do a linear lookup on the operators table */
for(;;) {
if(n >= SX_ARRAYSIZE(aOpTable)) {
break;
}
if(SyisAlpha(aOpTable[n].sOp.zString[0])) {
/* TICKET 1433-012: Alpha stream operators [i.e: new, clone, instanceof] */
rc = SyStringCmp(pStr, &aOpTable[n].sOp, SyStrnicmp);
} else {
rc = SyStringCmp(pStr, &aOpTable[n].sOp, SyMemcmp);
}
if(rc == 0) {
if(aOpTable[n].sOp.nByte != sizeof(char) || (aOpTable[n].iOp != EXPR_OP_UMINUS && aOpTable[n].iOp != EXPR_OP_UPLUS) || pLast == 0) {
/* There is no ambiguity here,simply return the first operator seen */
return &aOpTable[n];
}
/* Handle ambiguity */
if(pLast->nType & (PH7_TK_LPAREN/*'('*/ | PH7_TK_OCB/*'{'*/ | PH7_TK_OSB/*'['*/ | PH7_TK_COLON/*:*/ | PH7_TK_COMMA/*,'*/)) {
/* Unary operators have precedence here over binary operators */
return &aOpTable[n];
}
if(pLast->nType & PH7_TK_OP) {
const ph7_expr_op *pOp = (const ph7_expr_op *)pLast->pUserData;
/* Ticket 1433-31: Handle the '++','--' operators case */
if(pOp->iOp != EXPR_OP_INCR && pOp->iOp != EXPR_OP_DECR) {
/* Unary operators have precedence here over binary operators */
return &aOpTable[n];
}
}
}
++n; /* Next operator in the table */
}
/* No such operator */
return 0;
}
/*
* Delimit a set of token stream.
* This function take care of handling the nesting level and stops when it hit
* the end of the input or the ending token is found and the nesting level is zero.
*/
PH7_PRIVATE void PH7_DelimitNestedTokens(SyToken *pIn, SyToken *pEnd, sxu32 nTokStart, sxu32 nTokEnd, SyToken **ppEnd) {
SyToken *pCur = pIn;
sxi32 iNest = 1;
for(;;) {
if(pCur >= pEnd) {
break;
}
if(pCur->nType & nTokStart) {
/* Increment nesting level */
iNest++;
} else if(pCur->nType & nTokEnd) {
/* Decrement nesting level */
iNest--;
if(iNest <= 0) {
break;
}
}
/* Advance cursor */
pCur++;
}
/* Point to the end of the chunk */
*ppEnd = pCur;
}
/*
* Make sure we are dealing with a valid expression tree.
* This function check for balanced parenthesis,braces,brackets and so on.
* When errors,PH7 take care of generating the appropriate error message.
* Return SXRET_OK on success. Any other return value indicates syntax error.
*/
static sxi32 ExprVerifyNodes(ph7_gen_state *pGen, ph7_expr_node **apNode, sxi32 nNode) {
sxi32 iParen, iSquare, iQuesty, iBraces;
sxi32 i, rc;
if(nNode > 0 && apNode[0]->pOp && (apNode[0]->pOp->iOp == EXPR_OP_ADD || apNode[0]->pOp->iOp == EXPR_OP_SUB)) {
/* Fix and mark as an unary not binary plus/minus operator */
apNode[0]->pOp = PH7_ExprExtractOperator(&apNode[0]->pStart->sData, 0);
apNode[0]->pStart->pUserData = (void *)apNode[0]->pOp;
}
iParen = iSquare = iQuesty = iBraces = 0;
for(i = 0 ; i < nNode ; ++i) {
if(apNode[i]->pStart->nType & PH7_TK_LPAREN /*'('*/) {
if(i > 0 && (apNode[i - 1]->xCode == PH7_CompileVariable || apNode[i - 1]->xCode == PH7_CompileLiteral ||
(apNode[i - 1]->pStart->nType & (PH7_TK_ID | PH7_TK_KEYWORD | PH7_TK_SSTR | PH7_TK_DSTR | PH7_TK_RPAREN/*')'*/ | PH7_TK_CSB/*']'*/ | PH7_TK_CCB/*'}'*/)))) {
/* Ticket 1433-033: Take care to ignore alpha-stream [i.e: or,xor] operators followed by an opening parenthesis */
if((apNode[i - 1]->pStart->nType & PH7_TK_OP) == 0) {
/* We are dealing with a postfix [i.e: function call] operator
* not a simple left parenthesis. Mark the node.
*/
apNode[i]->pStart->nType |= PH7_TK_OP;
apNode[i]->pStart->pUserData = (void *)&sFCallOp; /* Function call operator */
apNode[i]->pOp = &sFCallOp;
}
}
iParen++;
} else if(apNode[i]->pStart->nType & PH7_TK_RPAREN/*')*/) {
if(iParen <= 0) {
rc = PH7_GenCompileError(&(*pGen), E_ERROR, apNode[i]->pStart->nLine, "Syntax error: Unexpected token ')'");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
iParen--;
} else if(apNode[i]->pStart->nType & PH7_TK_OSB /*'['*/) {
iSquare++;
} else if(apNode[i]->pStart->nType & PH7_TK_CSB /*']'*/) {
if(iSquare <= 0) {
rc = PH7_GenCompileError(&(*pGen), E_ERROR, apNode[i]->pStart->nLine, "Syntax error: Unexpected token ']'");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
iSquare--;
} else if(apNode[i]->pStart->nType & PH7_TK_OCB /*'{'*/ && apNode[i]->xCode != PH7_CompileArray) {
iBraces++;
if(i > 0 && (apNode[i - 1]->xCode == PH7_CompileVariable || (apNode[i - 1]->pStart->nType & PH7_TK_CSB/*]*/))) {
const ph7_expr_op *pOp, *pEnd;
int iNest = 1;
sxi32 j = i + 1;
/*
* Dirty Hack: $a{'x'} == > $a['x']
*/
apNode[i]->pStart->nType &= ~PH7_TK_OCB /*'{'*/;
apNode[i]->pStart->nType |= PH7_TK_OSB /*'['*/;
pOp = aOpTable;
pEnd = &pOp[sizeof(aOpTable)];
while(pOp < pEnd) {
if(pOp->iOp == EXPR_OP_SUBSCRIPT) {
break;
}
pOp++;
}
if(pOp >= pEnd) {
pOp = 0;
}
if(pOp) {
apNode[i]->pOp = pOp;
apNode[i]->pStart->nType |= PH7_TK_OP;
}
iBraces--;
iSquare++;
while(j < nNode) {
if(apNode[j]->pStart->nType & PH7_TK_OCB /*{*/) {
/* Increment nesting level */
iNest++;
} else if(apNode[j]->pStart->nType & PH7_TK_CCB/*}*/) {
/* Decrement nesting level */
iNest--;
if(iNest < 1) {
break;
}
}
j++;
}
if(j < nNode) {
apNode[j]->pStart->nType &= ~PH7_TK_CCB /*'}'*/;
apNode[j]->pStart->nType |= PH7_TK_CSB /*']'*/;
}
}
} else if(apNode[i]->pStart->nType & PH7_TK_CCB /*'}'*/) {
if(iBraces <= 0) {
rc = PH7_GenCompileError(&(*pGen), E_ERROR, apNode[i]->pStart->nLine, "Syntax error: Unexpected token '}'");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
iBraces--;
} else if(apNode[i]->pStart->nType & PH7_TK_COLON) {
if(iQuesty <= 0) {
rc = PH7_GenCompileError(&(*pGen), E_ERROR, apNode[i]->pStart->nLine, "Syntax error: Unexpected token ':'");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
iQuesty--;
} else if(apNode[i]->pStart->nType & PH7_TK_OP) {
const ph7_expr_op *pOp = (const ph7_expr_op *)apNode[i]->pOp;
if(pOp->iOp == EXPR_OP_QUESTY) {
iQuesty++;
} else if(i > 0 && (pOp->iOp == EXPR_OP_UMINUS || pOp->iOp == EXPR_OP_UPLUS)) {
if(apNode[i - 1]->xCode == PH7_CompileVariable || apNode[i - 1]->xCode == PH7_CompileLiteral) {
sxi32 iExprOp = EXPR_OP_SUB; /* Binary minus */
sxu32 n = 0;
if(pOp->iOp == EXPR_OP_UPLUS) {
iExprOp = EXPR_OP_ADD; /* Binary plus */
}
/*
* TICKET 1433-013: This is a fix around an obscure bug when the user uses
* a variable name which is an alpha-stream operator [i.e: $and,$xor,$eq..].
*/
while(n < SX_ARRAYSIZE(aOpTable) && aOpTable[n].iOp != iExprOp) {
++n;
}
pOp = &aOpTable[n];
/* Mark as binary '+' or '-',not an unary */
apNode[i]->pOp = pOp;
apNode[i]->pStart->pUserData = (void *)pOp;
}
}
}
}
if(iParen != 0 || iSquare != 0 || iQuesty != 0 || iBraces != 0) {
rc = PH7_GenCompileError(&(*pGen), E_ERROR, apNode[0]->pStart->nLine, "Syntax error, mismatched '(','[','{' or '?'");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
return SXRET_OK;
}
/*
* Collect and assemble tokens holding a namespace path [i.e: namespace\to\const]
* or a simple literal [i.e: PHP_EOL].
*/
static void ExprAssembleLiteral(SyToken **ppCur, SyToken *pEnd) {
SyToken *pIn = *ppCur;
/* Jump the first literal seen */
if((pIn->nType & PH7_TK_NSSEP) == 0) {
pIn++;
}
for(;;) {
if(pIn < pEnd && (pIn->nType & PH7_TK_NSSEP)) {
pIn++;
if(pIn < pEnd && (pIn->nType & (PH7_TK_ID | PH7_TK_KEYWORD))) {
pIn++;
}
} else {
break;
}
}
/* Synchronize pointers */
*ppCur = pIn;
}
/*
* Collect and assemble tokens holding closure body.
* When errors,PH7 take care of generating the appropriate error message.
* Anonymous functions, also known as closures, allow the creation of functions
* which have no specified name. They are most useful as the value of callback
* parameters, but they have many other uses.
* Closures may also inherit variables from the parent scope. Any such variables
* must be declared in the function header. Inheriting variables from the parent
* scope is not the same as using global variables. Global variables exist in the global scope
* which is the same no matter what function is executing. The parent scope of a closure is the
* function in which the closure was declared (not necessarily the function it was called from).
*
* Some example:
* $greet = function($name)
* {
* printf("Hello %s\r\n", $name);
* };
* $greet('World');
* $greet('AerScript');
*
* $double = function($a) {
* return $a * 2;
* };
* // This is our range of numbers
* $numbers = range(1, 5);
* // Use the Anonymous function as a callback here to
* // double the size of each element in our
* // range
* $new_numbers = array_map($double, $numbers);
* print(implode(' ', $new_numbers));
*/
static sxi32 ExprAssembleClosure(ph7_gen_state *pGen, SyToken **ppCur, SyToken *pEnd) {
SyToken *pIn = *ppCur;
sxu32 nLine;
sxi32 rc;
/* Jump the 'function' keyword */
nLine = pIn->nLine;
pIn++;
if(pIn < pEnd && (pIn->nType & (PH7_TK_ID | PH7_TK_KEYWORD))) {
pIn++;
}
if(pIn >= pEnd || (pIn->nType & PH7_TK_LPAREN) == 0) {
/* Syntax error */
rc = PH7_GenCompileError(&(*pGen), E_ERROR, nLine, "Missing opening parenthesis '(' while declaring anonymous function");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
goto Synchronize;
}
pIn++; /* Jump the leading parenthesis '(' */
PH7_DelimitNestedTokens(pIn, pEnd, PH7_TK_LPAREN/*'('*/, PH7_TK_RPAREN/*')'*/, &pIn);
if(pIn >= pEnd || &pIn[1] >= pEnd) {
/* Syntax error */
rc = PH7_GenCompileError(&(*pGen), E_ERROR, nLine, "Syntax error while declaring anonymous function");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
goto Synchronize;
}
pIn++; /* Jump the trailing parenthesis */
if(pIn->nType & PH7_TK_KEYWORD) {
sxu32 nKey = SX_PTR_TO_INT(pIn->pUserData);
/* Check if we are dealing with a closure */
if(nKey == PH7_KEYWORD_USING) {
pIn++; /* Jump the 'using' keyword */
if(pIn >= pEnd || (pIn->nType & PH7_TK_LPAREN) == 0) {
/* Syntax error */
rc = PH7_GenCompileError(&(*pGen), E_ERROR, nLine, "Syntax error while declaring anonymous function");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
goto Synchronize;
}
pIn++; /* Jump the leading parenthesis '(' */
PH7_DelimitNestedTokens(pIn, pEnd, PH7_TK_LPAREN/*'('*/, PH7_TK_RPAREN/*')'*/, &pIn);
if(pIn >= pEnd || &pIn[1] >= pEnd) {
/* Syntax error */
rc = PH7_GenCompileError(&(*pGen), E_ERROR, nLine, "Syntax error while declaring anonymous function");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
goto Synchronize;
}
pIn++;
} else {
/* Syntax error */
rc = PH7_GenCompileError(&(*pGen), E_ERROR, nLine, "Syntax error while declaring anonymous function");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
goto Synchronize;
}
}
if(pIn->nType & PH7_TK_OCB /*'{'*/) {
pIn++; /* Jump the leading curly '{' */
PH7_DelimitNestedTokens(pIn, pEnd, PH7_TK_OCB/*'{'*/, PH7_TK_CCB/*'}'*/, &pIn);
if(pIn < pEnd) {
pIn++;
}
} else {
/* Syntax error */
rc = PH7_GenCompileError(&(*pGen), E_ERROR, nLine, "Syntax error while declaring anonymous function,missing '{'");
if(rc == SXERR_ABORT) {
return SXERR_ABORT;
}
}
rc = SXRET_OK;
Synchronize:
/* Synchronize pointers */
*ppCur = pIn;
return rc;
}
/*
* Extract a single expression node from the input.
* On success store the freshly extracted node in ppNode.
* When errors,PH7 take care of generating the appropriate error message.
* An expression node can be a variable [i.e: $var],an operator [i.e: ++]
* an anonymous function [i.e: function(){ return "Hello"; }, a double/single
* quoted string, a literal [i.e: PHP_EOL],a namespace path
* [i.e: namespaces\path\to..],an array [i.e: {4,5,6}] and so on.
*/
static sxi32 ExprExtractNode(ph7_gen_state *pGen, ph7_expr_node **ppNode) {
ph7_expr_node *pNode;
SyToken *pCur;
sxi32 rc;
/* Allocate a new node */
pNode = (ph7_expr_node *)SyMemBackendPoolAlloc(&pGen->pVm->sAllocator, sizeof(ph7_expr_node));
if(pNode == 0) {
/* If the supplied memory subsystem is so sick that we are unable to allocate
* a tiny chunk of memory, there is no much we can do here.
*/
return SXERR_MEM;
}
/* Zero the structure */
SyZero(pNode, sizeof(ph7_expr_node));
SySetInit(&pNode->aNodeArgs, &pGen->pVm->sAllocator, sizeof(ph7_expr_node **));
/* Point to the head of the token stream */
pCur = pNode->pStart = pGen->pIn;
/* Start collecting tokens */
if(pCur->nType & PH7_TK_OP) {
/* Point to the instance that describe this operator */
pNode->pOp = (const ph7_expr_op *)pCur->pUserData;
/* Advance the stream cursor */
pCur++;
} else if(pCur->nType & PH7_TK_DOLLAR) {
/* Isolate variable */
while(pCur < pGen->pEnd && (pCur->nType & PH7_TK_DOLLAR)) {
pCur++; /* Variable variable */
}
if(pCur < pGen->pEnd) {
if(pCur->nType & (PH7_TK_ID | PH7_TK_KEYWORD)) {
/* Variable name */
pCur++;
} else if(pCur->nType & PH7_TK_OCB /* '{' */) {
pCur++;
/* Dynamic variable name,Collect until the next non nested '}' */
PH7_DelimitNestedTokens(pCur, pGen->pEnd, PH7_TK_OCB, PH7_TK_CCB, &pCur);
if(pCur < pGen->pEnd) {
pCur++;
} else {
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "Syntax error: Missing closing brace '}'");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
SyMemBackendPoolFree(&pGen->pVm->sAllocator, pNode);
return rc;
}
}
}
pNode->xCode = PH7_CompileVariable;
} else if(pCur->nType & PH7_TK_OCB /* '{' */) {
/* Array, assemble tokens */
pCur++;
PH7_DelimitNestedTokens(pCur, pGen->pEnd, PH7_TK_OCB /* '{' */, PH7_TK_CCB /* '}' */, &pCur);
if(pCur < pGen->pEnd) {
pCur++;
} else {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "Syntax error: Missing closing braces '}'");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
SyMemBackendPoolFree(&pGen->pVm->sAllocator, pNode);
return rc;
}
pNode->xCode = PH7_CompileArray;
} else if(pCur->nType & PH7_TK_KEYWORD) {
sxu32 nKeyword = (sxu32)SX_PTR_TO_INT(pCur->pUserData);
if(pCur[1].nType & PH7_TK_LPAREN && (nKeyword & PH7_KEYWORD_TYPEDEF)) {
/* Anonymous function */
if(&pCur[1] >= pGen->pEnd) {
/* Assume a literal */
ExprAssembleLiteral(&pCur, pGen->pEnd);
pNode->xCode = PH7_CompileLiteral;
} else {
/* Assemble anonymous functions body */
rc = ExprAssembleClosure(&(*pGen), &pCur, pGen->pEnd);
if(rc != SXRET_OK) {
SyMemBackendPoolFree(&pGen->pVm->sAllocator, pNode);
return rc;
}
pNode->xCode = PH7_CompileClosure;
}
} else {
/* Assume a literal */
ExprAssembleLiteral(&pCur, pGen->pEnd);
pNode->xCode = PH7_CompileLiteral;
}
} else if(pCur->nType & (PH7_TK_NSSEP | PH7_TK_ID)) {
/* Constants,function name,namespace path,class name... */
ExprAssembleLiteral(&pCur, pGen->pEnd);
pNode->xCode = PH7_CompileLiteral;
} else {
if((pCur->nType & (PH7_TK_LPAREN | PH7_TK_RPAREN | PH7_TK_COMMA | PH7_TK_COLON | PH7_TK_CSB | PH7_TK_OCB | PH7_TK_CCB)) == 0) {
/* Point to the code generator routine */
pNode->xCode = PH7_GetNodeHandler(pCur->nType);
if(pNode->xCode == 0) {
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "Syntax error: Unexpected token '%z'", &pNode->pStart->sData);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
SyMemBackendPoolFree(&pGen->pVm->sAllocator, pNode);
return rc;
}
}
/* Advance the stream cursor */
pCur++;
}
/* Point to the end of the token stream */
pNode->pEnd = pCur;
/* Save the node for later processing */
*ppNode = pNode;
/* Synchronize cursors */
pGen->pIn = pCur;
return SXRET_OK;
}
/*
* Point to the next expression that should be evaluated shortly.
* The cursor stops when it hit a comma ',' or a semi-colon and the nesting
* level is zero.
*/
PH7_PRIVATE sxi32 PH7_GetNextExpr(SyToken *pStart, SyToken *pEnd, SyToken **ppNext) {
SyToken *pCur = pStart;
sxi32 iNest = 0;
if(pCur >= pEnd || (pCur->nType & PH7_TK_SEMI/*';'*/)) {
/* Last expression */
return SXERR_EOF;
}
while(pCur < pEnd) {
if((pCur->nType & (PH7_TK_COMMA/*','*/ | PH7_TK_SEMI/*';'*/)) && iNest <= 0) {
break;
}
if(pCur->nType & (PH7_TK_LPAREN/*'('*/ | PH7_TK_OSB/*'['*/ | PH7_TK_OCB/*'{'*/)) {
iNest++;
} else if(pCur->nType & (PH7_TK_RPAREN/*')'*/ | PH7_TK_CSB/*']'*/ | PH7_TK_CCB/*'}*/)) {
iNest--;
}
pCur++;
}
*ppNext = pCur;
return SXRET_OK;
}
/*
* Free an expression tree.
*/
static void ExprFreeTree(ph7_gen_state *pGen, ph7_expr_node *pNode) {
if(pNode->pLeft) {
/* Release the left tree */
ExprFreeTree(&(*pGen), pNode->pLeft);
}
if(pNode->pRight) {
/* Release the right tree */
ExprFreeTree(&(*pGen), pNode->pRight);
}
if(pNode->pCond) {
/* Release the conditional tree used by the ternary operator */
ExprFreeTree(&(*pGen), pNode->pCond);
}
if(SySetUsed(&pNode->aNodeArgs) > 0) {
ph7_expr_node **apArg;
sxu32 n;
/* Release node arguments */
apArg = (ph7_expr_node **)SySetBasePtr(&pNode->aNodeArgs);
for(n = 0 ; n < SySetUsed(&pNode->aNodeArgs) ; ++n) {
ExprFreeTree(&(*pGen), apArg[n]);
}
SySetRelease(&pNode->aNodeArgs);
}
/* Finally,release this node */
SyMemBackendPoolFree(&pGen->pVm->sAllocator, pNode);
}
/*
* Free an expression tree.
* This function is a wrapper around ExprFreeTree() defined above.
*/
PH7_PRIVATE sxi32 PH7_ExprFreeTree(ph7_gen_state *pGen, SySet *pNodeSet) {
ph7_expr_node **apNode;
sxu32 n;
apNode = (ph7_expr_node **)SySetBasePtr(pNodeSet);
for(n = 0 ; n < SySetUsed(pNodeSet) ; ++n) {
if(apNode[n]) {
ExprFreeTree(&(*pGen), apNode[n]);
}
}
return SXRET_OK;
}
/*
* Check if the given node is a modifiable l/r-value.
* Return TRUE if modifiable.FALSE otherwise.
*/
static int ExprIsModifiableValue(ph7_expr_node *pNode, sxu8 bFunc) {
sxi32 iExprOp;
if(pNode->pOp == 0) {
return pNode->xCode == PH7_CompileVariable ? TRUE : FALSE;
}
iExprOp = pNode->pOp->iOp;
if(iExprOp == EXPR_OP_ARROW /*'->' */ || iExprOp == EXPR_OP_DC /*'::'*/) {
return TRUE;
}
if(iExprOp == EXPR_OP_SUBSCRIPT/*'[]'*/) {
if(pNode->pLeft->pOp) {
if(pNode->pLeft->pOp->iOp != EXPR_OP_SUBSCRIPT /*'['*/ && pNode->pLeft->pOp->iOp != EXPR_OP_ARROW /*'->'*/
&& pNode->pLeft->pOp->iOp != EXPR_OP_DC /*'::'*/) {
return FALSE;
}
} else if(pNode->pLeft->xCode != PH7_CompileVariable) {
return FALSE;
}
return TRUE;
}
if(bFunc && iExprOp == EXPR_OP_FUNC_CALL) {
return TRUE;
}
/* Not a modifiable l or r-value */
return FALSE;
}
/* Forward declaration */
static sxi32 ExprMakeTree(ph7_gen_state *pGen, ph7_expr_node **apNode, sxi32 nToken);
/* Macro to check if the given node is a terminal */
#define NODE_ISTERM(NODE) (apNode[NODE] && (!apNode[NODE]->pOp || apNode[NODE]->pLeft ))
/*
* Build an expression tree for each given function argument.
* When errors,PH7 take care of generating the appropriate error message.
*/
static sxi32 ExprProcessFuncArguments(ph7_gen_state *pGen, ph7_expr_node *pOp, ph7_expr_node **apNode, sxi32 nToken) {
sxi32 iNest, iCur, iNode;
sxi32 rc;
/* Process function arguments from left to right */
iCur = 0;
for(;;) {
if(iCur >= nToken) {
/* No more arguments to process */
break;
}
iNode = iCur;
iNest = 0;
while(iCur < nToken) {
if(apNode[iCur]) {
if((apNode[iCur]->pStart->nType & PH7_TK_COMMA) && apNode[iCur]->pLeft == 0 && iNest <= 0) {
break;
} else if(apNode[iCur]->pStart->nType & (PH7_TK_LPAREN | PH7_TK_OSB | PH7_TK_OCB)) {
iNest++;
} else if(apNode[iCur]->pStart->nType & (PH7_TK_RPAREN | PH7_TK_CCB | PH7_TK_CSB)) {
iNest--;
}
}
iCur++;
}
if(iCur > iNode) {
if(apNode[iNode] && (apNode[iNode]->pStart->nType & PH7_TK_AMPER /*'&'*/) && ((iCur - iNode) == 2)
&& apNode[iNode + 1]->xCode == PH7_CompileVariable) {
PH7_GenCompileError(&(*pGen), E_WARNING, apNode[iNode]->pStart->nLine,
"call-time pass-by-reference is deprecated");
ExprFreeTree(&(*pGen), apNode[iNode]);
apNode[iNode] = 0;
}
ExprMakeTree(&(*pGen), &apNode[iNode], iCur - iNode);
if(apNode[iNode]) {
/* Put a pointer to the root of the tree in the arguments set */
SySetPut(&pOp->aNodeArgs, (const void *)&apNode[iNode]);
} else {
/* Empty function argument */
rc = PH7_GenCompileError(&(*pGen), E_ERROR, pOp->pStart->nLine, "Empty function argument");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
} else {
rc = PH7_GenCompileError(&(*pGen), E_ERROR, pOp->pStart->nLine, "Missing function argument");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
/* Jump trailing comma */
if(iCur < nToken && apNode[iCur] && (apNode[iCur]->pStart->nType & PH7_TK_COMMA)) {
iCur++;
if(iCur >= nToken) {
/* missing function argument */
rc = PH7_GenCompileError(&(*pGen), E_ERROR, pOp->pStart->nLine, "Missing function argument");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
}
}
return SXRET_OK;
}
/*
* Create an expression tree from an array of tokens.
* If successful, the root of the tree is stored in apNode[0].
* When errors,PH7 take care of generating the appropriate error message.
*/
static sxi32 ExprMakeTree(ph7_gen_state *pGen, ph7_expr_node **apNode, sxi32 nToken) {
sxi32 i, iLeft, iRight;
ph7_expr_node *pNode;
sxi32 iCur;
sxi32 rc;
if(nToken <= 0 || (nToken == 1 && apNode[0]->xCode)) {
/* TICKET 1433-17: self evaluating node */
return SXRET_OK;
}
/* Process expressions enclosed in parenthesis first */
for(iCur = 0 ; iCur < nToken ; ++iCur) {
sxi32 iNest;
/* Note that, we use strict comparison here '!=' instead of the bitwise and '&' operator
* since the LPAREN token can also be an operator [i.e: Function call].
*/
if(apNode[iCur] == 0 || apNode[iCur]->pStart->nType != PH7_TK_LPAREN) {
continue;
}
iNest = 1;
iLeft = iCur;
/* Find the closing parenthesis */
iCur++;
while(iCur < nToken) {
if(apNode[iCur]) {
if(apNode[iCur]->pStart->nType & PH7_TK_RPAREN /* ')' */) {
/* Decrement nesting level */
iNest--;
if(iNest <= 0) {
break;
}
} else if(apNode[iCur]->pStart->nType & PH7_TK_LPAREN /* '(' */) {
/* Increment nesting level */
iNest++;
}
}
iCur++;
}
if(iCur - iLeft > 1) {
/* Recurse and process this expression */
rc = ExprMakeTree(&(*pGen), &apNode[iLeft + 1], iCur - iLeft - 1);
if(rc != SXRET_OK) {
return rc;
}
}
/* Free the left and right nodes */
ExprFreeTree(&(*pGen), apNode[iLeft]);
ExprFreeTree(&(*pGen), apNode[iCur]);
apNode[iLeft] = 0;
apNode[iCur] = 0;
}
/* Process expressions enclosed in braces */
for(iCur = 0 ; iCur < nToken ; ++iCur) {
sxi32 iNest;
/* Note that, we use strict comparison here '!=' instead of the bitwise and '&' operator
* since the OCB '{' token can also be an operator [i.e: subscripting].
*/
if(apNode[iCur] == 0 || apNode[iCur]->pStart->nType != PH7_TK_OCB || apNode[iCur]->xCode == PH7_CompileArray) {
continue;
}
iNest = 1;
iLeft = iCur;
/* Find the closing parenthesis */
iCur++;
while(iCur < nToken) {
if(apNode[iCur]) {
if(apNode[iCur]->pStart->nType & PH7_TK_CCB/*'}'*/) {
/* Decrement nesting level */
iNest--;
if(iNest <= 0) {
break;
}
} else if(apNode[iCur]->pStart->nType & PH7_TK_OCB /*'{'*/) {
/* Increment nesting level */
iNest++;
}
}
iCur++;
}
if(iCur - iLeft > 1) {
/* Recurse and process this expression */
rc = ExprMakeTree(&(*pGen), &apNode[iLeft + 1], iCur - iLeft - 1);
if(rc != SXRET_OK) {
return rc;
}
}
/* Free the left and right nodes */
ExprFreeTree(&(*pGen), apNode[iLeft]);
ExprFreeTree(&(*pGen), apNode[iCur]);
apNode[iLeft] = 0;
apNode[iCur] = 0;
}
/* Handle postfix [i.e: function call,subscripting,member access] operators with precedence 2 */
iLeft = -1;
for(iCur = 0 ; iCur < nToken ; ++iCur) {
if(apNode[iCur] == 0) {
continue;
}
pNode = apNode[iCur];
if(pNode->pOp && pNode->pOp->iPrec == 2 && pNode->pLeft == 0) {
if(pNode->pOp->iOp == EXPR_OP_FUNC_CALL) {
/* Collect function arguments */
sxi32 iPtr = 0;
sxi32 nFuncTok = 0;
while(nFuncTok + iCur < nToken) {
if(apNode[nFuncTok + iCur]) {
if(apNode[nFuncTok + iCur]->pStart->nType & PH7_TK_LPAREN /*'('*/) {
iPtr++;
} else if(apNode[nFuncTok + iCur]->pStart->nType & PH7_TK_RPAREN /*')'*/) {
iPtr--;
if(iPtr <= 0) {
break;
}
}
}
nFuncTok++;
}
if(nFuncTok + iCur >= nToken) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "Missing right parenthesis ')'");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
if(iLeft < 0 || !NODE_ISTERM(iLeft) /*|| ( apNode[iLeft]->pOp && apNode[iLeft]->pOp->iPrec != 2)*/) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "Invalid function name");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
if(nFuncTok > 1) {
/* Process function arguments */
rc = ExprProcessFuncArguments(&(*pGen), pNode, &apNode[iCur + 1], nFuncTok - 1);
if(rc != SXRET_OK) {
return rc;
}
}
/* Link the node to the tree */
pNode->pLeft = apNode[iLeft];
apNode[iLeft] = 0;
for(iPtr = 1; iPtr <= nFuncTok ; iPtr++) {
apNode[iCur + iPtr] = 0;
}
} else if(pNode->pOp->iOp == EXPR_OP_SUBSCRIPT) {
/* Subscripting */
sxi32 iArrTok = iCur + 1;
sxi32 iNest = 1;
if(iLeft < 0 || apNode[iLeft] == 0 || (apNode[iLeft]->pOp == 0 && (apNode[iLeft]->xCode != PH7_CompileVariable &&
apNode[iLeft]->xCode != PH7_CompileSimpleString && apNode[iLeft]->xCode != PH7_CompileString)) ||
(apNode[iLeft]->pOp && apNode[iLeft]->pOp->iPrec != 2 /* postfix */)) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "Invalid array name");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
/* Collect index tokens */
while(iArrTok < nToken) {
if(apNode[iArrTok]) {
if(apNode[iArrTok]->pOp && apNode[iArrTok]->pOp->iOp == EXPR_OP_SUBSCRIPT && apNode[iArrTok]->pLeft == 0) {
/* Increment nesting level */
iNest++;
} else if(apNode[iArrTok]->pStart->nType & PH7_TK_CSB /*']'*/) {
/* Decrement nesting level */
iNest--;
if(iNest <= 0) {
break;
}
}
}
++iArrTok;
}
if(iArrTok > iCur + 1) {
/* Recurse and process this expression */
rc = ExprMakeTree(&(*pGen), &apNode[iCur + 1], iArrTok - iCur - 1);
if(rc != SXRET_OK) {
return rc;
}
/* Link the node to it's index */
SySetPut(&pNode->aNodeArgs, (const void *)&apNode[iCur + 1]);
}
/* Link the node to the tree */
pNode->pLeft = apNode[iLeft];
pNode->pRight = 0;
apNode[iLeft] = 0;
for(iNest = iCur + 1 ; iNest <= iArrTok ; ++iNest) {
apNode[iNest] = 0;
}
} else {
/* Member access operators [i.e: '->','::'] */
iRight = iCur + 1;
while(iRight < nToken && apNode[iRight] == 0) {
iRight++;
}
if(iRight >= nToken || iLeft < 0 || !NODE_ISTERM(iRight) || !NODE_ISTERM(iLeft)) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Missing/Invalid member name", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
/* Link the node to the tree */
pNode->pLeft = apNode[iLeft];
if(pNode->pOp->iOp == EXPR_OP_ARROW /*'->'*/ && pNode->pLeft->pOp == 0 &&
pNode->pLeft->xCode != PH7_CompileVariable) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine,
"'%z': Expecting a variable as left operand", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
pNode->pRight = apNode[iRight];
apNode[iLeft] = apNode[iRight] = 0;
}
}
iLeft = iCur;
}
/* Handle left associative (new, clone) operators */
for(iCur = 0 ; iCur < nToken ; ++iCur) {
if(apNode[iCur] == 0) {
continue;
}
pNode = apNode[iCur];
if(pNode->pOp && pNode->pOp->iPrec == 1 && pNode->pLeft == 0) {
SyToken *pToken;
/* Get the left node */
iLeft = iCur + 1;
while(iLeft < nToken && apNode[iLeft] == 0) {
iLeft++;
}
if(iLeft >= nToken || !NODE_ISTERM(iLeft)) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Expecting class constructor call",
&pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
/* Make sure the operand are of a valid type */
if(pNode->pOp->iOp == EXPR_OP_CLONE) {
/* Clone:
* Symisc eXtension: 'clone' accepts now as it's left operand:
* ++ function call (including anonymous)
* ++ array member
* ++ 'new' operator
* Example:
* clone $pObj;
* clone obj(); // function obj(){ return new Class(); }
* clone $a['object']; // $a = array('object' => new Class());
*/
if(apNode[iLeft]->pOp == 0) {
if(apNode[iLeft]->xCode != PH7_CompileVariable) {
pToken = apNode[iLeft]->pStart;
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Unexpected token '%z'",
&pNode->pOp->sOp, &pToken->sData);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
}
} else {
/* New */
if(apNode[iLeft]->pOp == 0) {
ProcNodeConstruct xCons = apNode[iLeft]->xCode;
if(xCons != PH7_CompileVariable && xCons != PH7_CompileLiteral && xCons != PH7_CompileSimpleString) {
pToken = apNode[iLeft]->pStart;
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine,
"'%z': Unexpected token '%z', expecting literal, variable or constructor call",
&pNode->pOp->sOp, &pToken->sData);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
}
}
/* Link the node to the tree */
pNode->pLeft = apNode[iLeft];
apNode[iLeft] = 0;
pNode->pRight = 0; /* Paranoid */
}
}
/* Handle post/pre increment/decrement [i.e: ++/--] operators with precedence 3 */
iLeft = -1;
for(iCur = 0 ; iCur < nToken ; ++iCur) {
if(apNode[iCur] == 0) {
continue;
}
pNode = apNode[iCur];
if(pNode->pOp && pNode->pOp->iPrec == 3 && pNode->pLeft == 0) {
if(iLeft >= 0 && ((apNode[iLeft]->pOp && apNode[iLeft]->pOp->iPrec == 2 /* Postfix */)
|| apNode[iLeft]->xCode == PH7_CompileVariable)) {
/* Link the node to the tree */
pNode->pLeft = apNode[iLeft];
apNode[iLeft] = 0;
}
}
iLeft = iCur;
}
iLeft = -1;
for(iCur = nToken - 1 ; iCur >= 0 ; iCur--) {
if(apNode[iCur] == 0) {
continue;
}
pNode = apNode[iCur];
if(pNode->pOp && pNode->pOp->iPrec == 3 && pNode->pLeft == 0) {
if(iLeft < 0 || (apNode[iLeft]->pOp == 0 && apNode[iLeft]->xCode != PH7_CompileVariable)
|| (apNode[iLeft]->pOp && apNode[iLeft]->pOp->iPrec != 2 /* Postfix */)) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z' operator needs l-value", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
/* Link the node to the tree */
pNode->pLeft = apNode[iLeft];
apNode[iLeft] = 0;
/* Mark as pre-increment/decrement node */
pNode->iFlags |= EXPR_NODE_PRE_INCR;
}
iLeft = iCur;
}
/* Handle right associative unary and cast operators [i.e: !,(string),~...] with precedence 4*/
iLeft = 0;
for(iCur = nToken - 1 ; iCur >= 0 ; iCur--) {
if(apNode[iCur]) {
pNode = apNode[iCur];
if(pNode->pOp && pNode->pOp->iPrec == 4 && pNode->pLeft == 0) {
if(iLeft > 0) {
/* Link the node to the tree */
pNode->pLeft = apNode[iLeft];
apNode[iLeft] = 0;
if(pNode->pLeft && pNode->pLeft->pOp && pNode->pLeft->pOp->iPrec > 4) {
if(pNode->pLeft->pLeft == 0 || pNode->pLeft->pRight == 0) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pLeft->pStart->nLine, "'%z': Missing operand", &pNode->pLeft->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
}
} else {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Missing operand", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
}
/* Save terminal position */
iLeft = iCur;
}
}
/* Process left and non-associative binary operators [i.e: *,/,&&,||...]*/
for(i = 7 ; i < 18 ; i++) {
iLeft = -1;
for(iCur = 0 ; iCur < nToken ; ++iCur) {
if(apNode[iCur] == 0) {
continue;
}
pNode = apNode[iCur];
if(pNode->pOp && pNode->pOp->iPrec == i && pNode->pLeft == 0) {
/* Get the right node */
iRight = iCur + 1;
while(iRight < nToken && apNode[iRight] == 0) {
iRight++;
}
if(iRight >= nToken || iLeft < 0 || !NODE_ISTERM(iRight) || !NODE_ISTERM(iLeft)) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Missing/Invalid operand", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
if(pNode->pOp->iOp == EXPR_OP_REF) {
sxi32 iTmp;
/* Reference operator [i.e: '&=' ]*/
if(ExprIsModifiableValue(apNode[iLeft], FALSE) == FALSE || (apNode[iLeft]->pOp && apNode[iLeft]->pOp->iVmOp == PH7_OP_MEMBER /*->,::*/)) {
/* Left operand must be a modifiable l-value */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'&': Left operand must be a modifiable l-value");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
if(apNode[iLeft]->pOp == 0 || apNode[iLeft]->pOp->iOp != EXPR_OP_SUBSCRIPT /*$a[] =& 14*/) {
if(ExprIsModifiableValue(apNode[iRight], TRUE) == FALSE) {
if(apNode[iRight]->pOp == 0 || (apNode[iRight]->pOp->iOp != EXPR_OP_NEW /* new */
&& apNode[iRight]->pOp->iOp != EXPR_OP_CLONE /* clone */)) {
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine,
"Reference operator '&' require a variable not a constant expression as it's right operand");
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
}
}
/* Swap operands */
iTmp = iRight;
iRight = iLeft;
iLeft = iTmp;
}
/* Link the node to the tree */
pNode->pLeft = apNode[iLeft];
pNode->pRight = apNode[iRight];
apNode[iLeft] = apNode[iRight] = 0;
}
iLeft = iCur;
}
}
/* Handle the ternary operator. (expr1) ? (expr2) : (expr3)
* Note that we do not need a precedence loop here since
* we are dealing with a single operator.
*/
iLeft = -1;
for(iCur = 0 ; iCur < nToken ; ++iCur) {
if(apNode[iCur] == 0) {
continue;
}
pNode = apNode[iCur];
if(pNode->pOp && pNode->pOp->iOp == EXPR_OP_QUESTY && pNode->pLeft == 0) {
sxi32 iNest = 1;
if(iLeft < 0 || !NODE_ISTERM(iLeft)) {
/* Missing condition */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Syntax error", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
/* Get the right node */
iRight = iCur + 1;
while(iRight < nToken) {
if(apNode[iRight]) {
if(apNode[iRight]->pOp && apNode[iRight]->pOp->iOp == EXPR_OP_QUESTY && apNode[iRight]->pCond == 0) {
/* Increment nesting level */
++iNest;
} else if(apNode[iRight]->pStart->nType & PH7_TK_COLON /*:*/) {
/* Decrement nesting level */
--iNest;
if(iNest <= 0) {
break;
}
}
}
iRight++;
}
if(iRight > iCur + 1) {
/* Recurse and process the then expression */
rc = ExprMakeTree(&(*pGen), &apNode[iCur + 1], iRight - iCur - 1);
if(rc != SXRET_OK) {
return rc;
}
/* Link the node to the tree */
pNode->pLeft = apNode[iCur + 1];
} else {
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Missing 'then' expression", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
apNode[iCur + 1] = 0;
if(iRight + 1 < nToken) {
/* Recurse and process the else expression */
rc = ExprMakeTree(&(*pGen), &apNode[iRight + 1], nToken - iRight - 1);
if(rc != SXRET_OK) {
return rc;
}
/* Link the node to the tree */
pNode->pRight = apNode[iRight + 1];
apNode[iRight + 1] = apNode[iRight] = 0;
} else {
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Missing 'else' expression", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
/* Point to the condition */
pNode->pCond = apNode[iLeft];
apNode[iLeft] = 0;
break;
}
iLeft = iCur;
}
/* Process right associative binary operators [i.e: '=','+=','/=']
* Note: All right associative binary operators have precedence 18
* so there is no need for a precedence loop here.
*/
iRight = -1;
for(iCur = nToken - 1 ; iCur >= 0 ; iCur--) {
if(apNode[iCur] == 0) {
continue;
}
pNode = apNode[iCur];
if(pNode->pOp && pNode->pOp->iPrec == 19 && pNode->pLeft == 0) {
/* Get the left node */
iLeft = iCur - 1;
while(iLeft >= 0 && apNode[iLeft] == 0) {
iLeft--;
}
if(iLeft < 0 || iRight < 0 || !NODE_ISTERM(iRight) || !NODE_ISTERM(iLeft)) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Missing/Invalid operand", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
if(ExprIsModifiableValue(apNode[iLeft], FALSE) == FALSE) {
if(pNode->pOp->iVmOp != PH7_OP_STORE) {
/* Left operand must be a modifiable l-value */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine,
"'%z': Left operand must be a modifiable l-value", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
}
/* Link the node to the tree (Reverse) */
pNode->pLeft = apNode[iRight];
pNode->pRight = apNode[iLeft];
apNode[iLeft] = apNode[iRight] = 0;
}
iRight = iCur;
}
/* Process left associative binary operators that have the lowest precedence [i.e: and,or,xor] */
for(i = 20 ; i < 24 ; i++) {
iLeft = -1;
for(iCur = 0 ; iCur < nToken ; ++iCur) {
if(apNode[iCur] == 0) {
continue;
}
pNode = apNode[iCur];
if(pNode->pOp && pNode->pOp->iPrec == i && pNode->pLeft == 0) {
/* Get the right node */
iRight = iCur + 1;
while(iRight < nToken && apNode[iRight] == 0) {
iRight++;
}
if(iRight >= nToken || iLeft < 0 || !NODE_ISTERM(iRight) || !NODE_ISTERM(iLeft)) {
/* Syntax error */
rc = PH7_GenCompileError(pGen, E_ERROR, pNode->pStart->nLine, "'%z': Missing/Invalid operand", &pNode->pOp->sOp);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
/* Link the node to the tree */
pNode->pLeft = apNode[iLeft];
pNode->pRight = apNode[iRight];
apNode[iLeft] = apNode[iRight] = 0;
}
iLeft = iCur;
}
}
/* Point to the root of the expression tree */
for(iCur = 1 ; iCur < nToken ; ++iCur) {
if(apNode[iCur]) {
if((apNode[iCur]->pOp || apNode[iCur]->xCode) && apNode[0] != 0) {
rc = PH7_GenCompileError(pGen, E_ERROR, apNode[iCur]->pStart->nLine, "Unexpected token '%z'", &apNode[iCur]->pStart->sData);
if(rc != SXERR_ABORT) {
rc = SXERR_SYNTAX;
}
return rc;
}
apNode[0] = apNode[iCur];
apNode[iCur] = 0;
}
}
return SXRET_OK;
}
/*
* Build an expression tree from the freshly extracted raw tokens.
* If successful, the root of the tree is stored in ppRoot.
* When errors,PH7 take care of generating the appropriate error message.
* This is the public interface used by the most code generator routines.
*/
PH7_PRIVATE sxi32 PH7_ExprMakeTree(ph7_gen_state *pGen, SySet *pExprNode, ph7_expr_node **ppRoot) {
ph7_expr_node **apNode;
ph7_expr_node *pNode;
sxi32 rc;
/* Reset node container */
SySetReset(pExprNode);
pNode = 0; /* Prevent compiler warning */
/* Extract nodes one after one until we hit the end of the input */
while(pGen->pIn < pGen->pEnd) {
rc = ExprExtractNode(&(*pGen), &pNode);
if(rc != SXRET_OK) {
return rc;
}
/* Save the extracted node */
SySetPut(pExprNode, (const void *)&pNode);
}
if(SySetUsed(pExprNode) < 1) {
/* Empty expression [i.e: A semi-colon;] */
*ppRoot = 0;
return SXRET_OK;
}
apNode = (ph7_expr_node **)SySetBasePtr(pExprNode);
/* Make sure we are dealing with valid nodes */
rc = ExprVerifyNodes(&(*pGen), apNode, (sxi32)SySetUsed(pExprNode));
if(rc != SXRET_OK) {
/* Don't worry about freeing memory,upper layer will
* cleanup the mess left behind.
*/
*ppRoot = 0;
return rc;
}
/* Build the tree */
rc = ExprMakeTree(&(*pGen), apNode, (sxi32)SySetUsed(pExprNode));
if(rc != SXRET_OK) {
/* Something goes wrong [i.e: Syntax error] */
*ppRoot = 0;
return rc;
}
/* Point to the root of the tree */
*ppRoot = apNode[0];
return SXRET_OK;
}
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