jsscan.h

java script test programing source code

};

struct JSToken {
    JSTokenType         type;           /* char value or above enumerator */
    JSTokenPos          pos;            /* token position in file */
    jschar              *ptr;           /* beginning of token in line buffer */
    union {
        struct {                        /* non-numeric literal */
            JSOp        op;             /* operator, for minimal parser */
            JSAtom      *atom;          /* atom table entry */
        } s;
        struct {                        /* atom pair, for XML PIs */
            JSAtom      *atom2;         /* auxiliary atom table entry */
            JSAtom      *atom;          /* main atom table entry */
        } p;
        jsdouble        dval;           /* floating point number */
    } u;
};

#define t_op            u.s.op
#define t_atom          u.s.atom
#define t_atom2         u.p.atom2
#define t_dval          u.dval

typedef struct JSTokenBuf {
    jschar              *base;          /* base of line or stream buffer */
    jschar              *limit;         /* limit for quick bounds check */
    jschar              *ptr;           /* next char to get, or slot to use */
} JSTokenBuf;

#define JS_LINE_LIMIT   256             /* logical line buffer size limit --
                                           physical line length is unlimited */
#define NTOKENS         4               /* 1 current + 2 lookahead, rounded */
#define NTOKENS_MASK    (NTOKENS-1)     /* to power of 2 to avoid divmod by 3 */

struct JSTokenStream {
    JSToken             tokens[NTOKENS];/* circular token buffer */
    uintN               cursor;         /* index of last parsed token */
    uintN               lookahead;      /* count of lookahead tokens */
    uintN               lineno;         /* current line number */
    uintN               ungetpos;       /* next free char slot in ungetbuf */
    jschar              ungetbuf[6];    /* at most 6, for \uXXXX lookahead */
    uintN               flags;          /* flags -- see below */
    ptrdiff_t           linelen;        /* physical linebuf segment length */
    ptrdiff_t           linepos;        /* linebuf offset in physical line */
    JSTokenBuf          linebuf;        /* line buffer for diagnostics */
    JSTokenBuf          userbuf;        /* user input buffer if !file */
    JSStringBuffer      tokenbuf;       /* current token string buffer */
    const char          *filename;      /* input filename or null */
    FILE                *file;          /* stdio stream if reading from file */
    JSPrincipals        *principals;    /* principals associated with source */
    JSSourceHandler     listener;       /* callback for source; eg debugger */
    void                *listenerData;  /* listener 'this' data */
    void                *listenerTSData;/* listener data for this TokenStream */
    jschar              *saveEOL;       /* save next end of line in userbuf, to
                                           optimize for very long lines */
};

#define CURRENT_TOKEN(ts)       ((ts)->tokens[(ts)->cursor])
#define ON_CURRENT_LINE(ts,pos) ((uint16)(ts)->lineno == (pos).end.lineno)

/* JSTokenStream flags */
#define TSF_ERROR       0x01            /* fatal error while compiling */
#define TSF_EOF         0x02            /* hit end of file */
#define TSF_NEWLINES    0x04            /* tokenize newlines */
#define TSF_OPERAND     0x08            /* looking for operand, not operator */
#define TSF_NLFLAG      0x20            /* last linebuf ended with \n */
#define TSF_CRFLAG      0x40            /* linebuf would have ended with \r */
#define TSF_DIRTYLINE   0x80            /* non-whitespace since start of line */
#define TSF_OWNFILENAME 0x100           /* ts->filename is malloc'd */
#define TSF_XMLTAGMODE  0x200           /* scanning within an XML tag in E4X */
#define TSF_XMLTEXTMODE 0x400           /* scanning XMLText terminal from E4X */
#define TSF_XMLONLYMODE 0x800           /* don't scan {expr} within text/tag */

/* Flag indicating unexpected end of input, i.e. TOK_EOF not at top-level. */
#define TSF_UNEXPECTED_EOF 0x1000

/*
 * To handle the hard case of contiguous HTML comments, we want to clear the
 * TSF_DIRTYINPUT flag at the end of each such comment.  But we'd rather not
 * scan for --> within every //-style comment unless we have to.  So we set
 * TSF_IN_HTML_COMMENT when a <!-- is scanned as an HTML begin-comment, and
 * clear it (and TSF_DIRTYINPUT) when we scan --> either on a clean line, or
 * only if (ts->flags & TSF_IN_HTML_COMMENT), in a //-style comment.
 *
 * This still works as before given a malformed comment hiding hack such as:
 *
 *    <script>
 *      <!-- comment hiding hack #1
 *      code goes here
 *      // --> oops, markup for script-unaware browsers goes here!
 *    </script>
 *
 * It does not cope with malformed comment hiding hacks where --> is hidden
 * by C-style comments, or on a dirty line.  Such cases are already broken.
 */
#define TSF_IN_HTML_COMMENT 0x2000

/* Ignore keywords and return TOK_NAME instead to the parser. */
#define TSF_KEYWORD_IS_NAME 0x4000

/* Unicode separators that are treated as line terminators, in addition to \n, \r */
#define LINE_SEPARATOR  0x2028
#define PARA_SEPARATOR  0x2029

/*
 * Create a new token stream, either from an input buffer or from a file.
 * Return null on file-open or memory-allocation failure.
 *
 * NB: All of js_New{,Buffer,File}TokenStream() return a pointer to transient
 * memory in the current context's temp pool.  This memory is deallocated via
 * JS_ARENA_RELEASE() after parsing is finished.
 */
extern JSTokenStream *
js_NewTokenStream(JSContext *cx, const jschar *base, size_t length,
                  const char *filename, uintN lineno, JSPrincipals *principals);

extern JS_FRIEND_API(JSTokenStream *)
js_NewBufferTokenStream(JSContext *cx, const jschar *base, size_t length);

extern JS_FRIEND_API(JSTokenStream *)
js_NewFileTokenStream(JSContext *cx, const char *filename, FILE *defaultfp);

extern JS_FRIEND_API(JSBool)
js_CloseTokenStream(JSContext *cx, JSTokenStream *ts);

extern JS_FRIEND_API(int)
js_fgets(char *buf, int size, FILE *file);

/*
 * If the given char array forms JavaScript keyword, return corresponding
 * token. Otherwise return TOK_EOF.
 */
extern JSTokenType
js_CheckKeyword(const jschar *chars, size_t length);

#define js_IsKeyword(chars, length) \
    (js_CheckKeyword(chars, length) != TOK_EOF)

/*
 * Friend-exported API entry point to call a mapping function on each reserved
 * identifier in the scanner's keyword table.
 */
extern JS_FRIEND_API(void)
js_MapKeywords(void (*mapfun)(const char *));

/*
 * Report a compile-time error by its number, using ts or cg to show context.
 * Return true for a warning, false for an error.
 */
extern JSBool
js_ReportCompileErrorNumber(JSContext *cx, void *handle, uintN flags,
                            uintN errorNumber, ...);

extern JSBool
js_ReportCompileErrorNumberUC(JSContext *cx, void *handle, uintN flags,
                              uintN errorNumber, ...);

/* Steal some JSREPORT_* bits (see jsapi.h) to tell handle's type. */
#define JSREPORT_HANDLE 0x300
#define JSREPORT_TS     0x000
#define JSREPORT_CG     0x100
#define JSREPORT_PN     0x200

/*
 * Look ahead one token and return its type.
 */
extern JSTokenType
js_PeekToken(JSContext *cx, JSTokenStream *ts);

extern JSTokenType
js_PeekTokenSameLine(JSContext *cx, JSTokenStream *ts);

/*
 * Get the next token from ts.
 */
extern JSTokenType
js_GetToken(JSContext *cx, JSTokenStream *ts);

/*
 * Push back the last scanned token onto ts.
 */
extern void
js_UngetToken(JSTokenStream *ts);

/*
 * Get the next token from ts if its type is tt.
 */
extern JSBool
js_MatchToken(JSContext *cx, JSTokenStream *ts, JSTokenType tt);

JS_END_EXTERN_C

#endif /* jsscan_h___ */