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/* Copyright (C) 1989, 2000 Aladdin Enterprises.  All rights reserved.

  This software is provided AS-IS with no warranty, either express or

  implied.

  This software is distributed under license and may not be copied,

  modified or distributed except as expressly authorized under the terms

  of the license contained in the file LICENSE in this distribution.

  For more information about licensing, please refer to

  http://www.ghostscript.com/licensing/. For information on

  commercial licensing, go to http://www.artifex.com/licensing/ or

  contact Artifex Software, Inc., 101 Lucas Valley Road #110,

  San Rafael, CA  94903, U.S.A., +1(415)492-9861.

*/

/* $Id: iscan.c,v 1.20 2005/04/25 12:28:49 igor Exp $ */

/* Token scanner for Ghostscript interpreter */

#include "ghost.h"

#include "memory_.h"

#include "stream.h"

#include "ierrors.h"

#include "btoken.h"		/* for ref_binary_object_format */

#include "files.h"		/* for fptr */

#include "ialloc.h"

#include "idict.h"		/* for //name lookup */

#include "dstack.h"		/* ditto */

#include "ilevel.h"

#include "iname.h"

#include "ipacked.h"

#include "iparray.h"

#include "strimpl.h"		/* for string decoding */

#include "sa85d.h"		/* ditto */

#include "sfilter.h"		/* ditto */

#include "ostack.h"		/* for accumulating proc bodies; */

					/* must precede iscan.h */

#include "iscan.h"		/* defines interface */

#include "iscanbin.h"

#include "iscannum.h"

#include "istream.h"

#include "istruct.h"		/* for RELOC_REF_VAR */

#include "iutil.h"

#include "ivmspace.h"

#include "store.h"

#include "scanchar.h"

#define recognize_btokens()\

  (ref_binary_object_format.value.intval != 0 && level2_enabled)

/* Procedure for handling DSC comments if desired. */

/* Set at initialization if a DSC handling module is included. */

int (*scan_dsc_proc) (const byte *, uint) = NULL;

/* Procedure for handling all comments if desired. */

/* Set at initialization if a comment handling module is included. */

/* If both scan_comment_proc and scan_dsc_proc are set, */

/* scan_comment_proc is called only for non-DSC comments. */

int (*scan_comment_proc) (const byte *, uint) = NULL;

/*

 * Level 2 includes some changes in the scanner:

 *      - \ is always recognized in strings, regardless of the data source;

 *      - << and >> are legal tokens;

 *      - <~ introduces an ASCII85 encoded string (terminated by ~>);

 *      - Character codes above 127 introduce binary objects.

 * We explicitly enable or disable these changes here.

 */

#define scan_enable_level2 level2_enabled	/* from ilevel.h */

/* ------ Dynamic strings ------ */

/* Begin collecting a dynamically allocated string. */

inline private void

dynamic_init(da_ptr pda, gs_memory_t *mem)

{

    pda->is_dynamic = false;

    pda->limit = pda->buf + da_buf_size;

    pda->next = pda->base = pda->buf;

    pda->memory = mem;

}

/* Free a dynamic string. */

private void

dynamic_free(da_ptr pda)

{

    if (pda->is_dynamic)

	gs_free_string(pda->memory, pda->base, da_size(pda), "scanner");

}

/* Resize a dynamic string. */

/* If the allocation fails, return e_VMerror; otherwise, return 0. */

private int

dynamic_resize(da_ptr pda, uint new_size)

{

    uint old_size = da_size(pda);

    uint pos = pda->next - pda->base;

    gs_memory_t *mem = pda->memory;

    byte *base;

    if (pda->is_dynamic) {

	base = gs_resize_string(mem, pda->base, old_size,

				new_size, "scanner");

	if (base == 0)

	    return_error(e_VMerror);

    } else {			/* switching from static to dynamic */

	base = gs_alloc_string(mem, new_size, "scanner");

	if (base == 0)

	    return_error(e_VMerror);

	memcpy(base, pda->base, min(old_size, new_size));

	pda->is_dynamic = true;

    }

    pda->base = base;

    pda->next = base + pos;

    pda->limit = base + new_size;

    return 0;

}

/* Grow a dynamic string. */

/* Return 0 if the allocation failed, the new 'next' ptr if OK. */

/* Return 0 or an error code, updating pda->next to point to the first */

/* available byte after growing. */

private int

dynamic_grow(da_ptr pda, byte * next, uint max_size)

{

    uint old_size = da_size(pda);

    uint new_size = (old_size < 10 ? 20 :

		     old_size >= (max_size >> 1) ? max_size :

		     old_size << 1);

    int code;

    pda->next = next;

    if (old_size == max_size)

	return_error(e_limitcheck);

    while ((code = dynamic_resize(pda, new_size)) < 0 &&

	   new_size > old_size

	) {			/* Try trimming down the requested new size. */

	new_size -= (new_size - old_size + 1) >> 1;

    }

    return code;

}

/* Ensure that a dynamic string is either on the heap or in the */

/* private buffer. */

private void

dynamic_save(da_ptr pda)

{

    if (!pda->is_dynamic && pda->base != pda->buf) {

	memcpy(pda->buf, pda->base, da_size(pda));

	pda->next = pda->buf + da_size(pda);

	pda->base = pda->buf;

    }

}

/* Finish collecting a dynamic string. */

private int

dynamic_make_string(i_ctx_t *i_ctx_p, ref * pref, da_ptr pda, byte * next)

{

    uint size = (pda->next = next) - pda->base;

    int code = dynamic_resize(pda, size);

    if (code < 0)

	return code;

    make_tasv_new(pref, t_string,

		  a_all | imemory_space((gs_ref_memory_t *) pda->memory),

		  size, bytes, pda->base);

    return 0;

}

/* ------ Main scanner ------ */

/* GC procedures */

#define ssarray ssptr->s_ss.binary.bin_array

private 

CLEAR_MARKS_PROC(scanner_clear_marks)

{

    scanner_state *const ssptr = vptr;

    r_clear_attrs(&ssarray, l_mark);

}

private 

ENUM_PTRS_WITH(scanner_enum_ptrs, scanner_state *ssptr) return 0;

case 0:

    if (ssptr->s_scan_type == scanning_none ||

	!ssptr->s_da.is_dynamic

	)

	ENUM_RETURN(0);

    return ENUM_STRING2(ssptr->s_da.base, da_size(&ssptr->s_da));

case 1:

    if (ssptr->s_scan_type != scanning_binary)

	return 0;

    ENUM_RETURN_REF(&ssarray);

ENUM_PTRS_END

private RELOC_PTRS_WITH(scanner_reloc_ptrs, scanner_state *ssptr)

{

    if (ssptr->s_scan_type != scanning_none && ssptr->s_da.is_dynamic) {

	gs_string sda;

	sda.data = ssptr->s_da.base;

	sda.size = da_size(&ssptr->s_da);

	RELOC_STRING_VAR(sda);

	ssptr->s_da.limit = sda.data + sda.size;

	ssptr->s_da.next = sda.data + (ssptr->s_da.next - ssptr->s_da.base);

	ssptr->s_da.base = sda.data;

    }

    if (ssptr->s_scan_type == scanning_binary) {

	RELOC_REF_VAR(ssarray);

	r_clear_attrs(&ssarray, l_mark);

    }

}

RELOC_PTRS_END

/* Structure type */

public_st_scanner_state();

/* Initialize a scanner. */

void

scanner_state_init_options(scanner_state *sstate, int options)

{

    sstate->s_scan_type = scanning_none;

    sstate->s_pstack = 0;

    sstate->s_options = options;

}

/* Handle a scan_Refill return from scan_token. */

/* This may return o_push_estack, 0 (meaning just call scan_token again), */

/* or an error code. */

int

scan_handle_refill(i_ctx_t *i_ctx_p, const ref * fop, scanner_state * sstate,

		   bool save, bool push_file, op_proc_t cont)

{

    stream *s = fptr(fop);

    uint avail = sbufavailable(s);

    int status;

    if (s->end_status == EOFC) {

	/* More data needed, but none available, so this is a syntax error. */

	return_error(e_syntaxerror);

    }

    status = s_process_read_buf(s);

    if (sbufavailable(s) > avail)

	return 0;

    if (status == 0)

	status = s->end_status;

    switch (status) {

	case EOFC:

	    /* We just discovered that we're at EOF. */

	    /* Let the caller find this out. */

	    return 0;

	case ERRC:

	    return_error(e_ioerror);

	case INTC:

	case CALLC:

	    {

		ref rstate[2];

		scanner_state *pstate;

		int nstate = (push_file ? 2 : 1);

		if (save) {

		    pstate =

			ialloc_struct(scanner_state, &st_scanner_state,

				      "scan_handle_refill");

		    if (pstate == 0)

			return_error(e_VMerror);

		    *pstate = *sstate;

		} else

		    pstate = sstate;

		/* If push_file is true, we want to push the file on the */

		/* o-stack before the state, for the continuation proc. */

		/* Since the refs passed to s_handle_read_exception */

		/* are pushed on the e-stack, we must ensure they are */

		/* literal, and also pass them in the opposite order! */

		make_istruct(&rstate[0], 0, pstate);

		rstate[1] = *fop;

		r_clear_attrs(&rstate[1], a_executable);

		return s_handle_read_exception(i_ctx_p, status, fop,

					       rstate, nstate, cont);

	    }

    }

    /* No more data available, but no exception.  How can this be? */

    lprintf("Can't refill scanner input buffer!");

    return_error(e_Fatal);

}

/*

 * Handle a comment.  The 'saved' argument is needed only for

 * tracing printout.

 */

private int

scan_comment(i_ctx_t *i_ctx_p, ref *pref, scanner_state *pstate,

	     const byte * base, const byte * end, bool saved)

{

    uint len = (uint) (end - base);

    int code;

#ifdef DEBUG

    const char *sstr = (saved ? ">" : "");

#endif

    if (len > 1 && (base[1] == '%' || base[1] == '!')) {

	/* Process as a DSC comment if requested. */

#ifdef DEBUG

	if (gs_debug_c('%')) {

	    dlprintf2("[%%%%%s%c]", sstr, (len >= 3 ? '+' : '-'));

	    debug_print_string(base, len);

	    dputs("\n");

	}

#endif

	if (scan_dsc_proc != NULL) {

	    code = scan_dsc_proc(base, len);

	    return (code < 0 ? code : 0);

	}

	if (pstate->s_options & SCAN_PROCESS_DSC_COMMENTS) {

	    code = scan_DSC_Comment;

	    goto comment;

	}

	/* Treat as an ordinary comment. */

    }

#ifdef DEBUG

    else {

	if (gs_debug_c('%')) {

	    dlprintf2("[%% %s%c]", sstr, (len >= 2 ? '+' : '-'));

	    debug_print_string(base, len);

	    dputs("\n");

	}

    }

#endif

    if (scan_comment_proc != NULL) {

	code = scan_comment_proc(base, len);

	return (code < 0 ? code : 0);

    }

    if (pstate->s_options & SCAN_PROCESS_COMMENTS) {

	code = scan_Comment;

	goto comment;

    }

    return 0;

 comment:

    {

	byte *cstr = ialloc_string(len, "scan_comment");

	if (cstr == 0)

	    return_error(e_VMerror);

	memcpy(cstr, base, len);

	make_string(pref, a_all | icurrent_space, len, cstr);

    }

    return code;

}

/* Read a token from a string. */

/* Update the string if succesful. */

int

scan_string_token_options(i_ctx_t *i_ctx_p, ref * pstr, ref * pref,

			  int options)

{

    stream st;

    stream *s = &st;

    scanner_state state;

    int code;

    if (!r_has_attr(pstr, a_read))

	return_error(e_invalidaccess);

    s_init(s, NULL);

    sread_string(s, pstr->value.bytes, r_size(pstr));

    scanner_state_init_options(&state, options | SCAN_FROM_STRING);

    switch (code = scan_token(i_ctx_p, s, pref, &state)) {

	default:		/* error or comment */

	    if (code < 0)

		break;

	    /* falls through */

	case 0:		/* read a token */

	case scan_BOS:

	    {

		uint pos = stell(s);

		pstr->value.bytes += pos;

		r_dec_size(pstr, pos);

	    }

	    break;

	case scan_Refill:	/* error */

	    code = gs_note_error(e_syntaxerror);

	case scan_EOF:

	    break;

    }

    return code;

}

/*

 * Read a token from a stream.  Return 0 if an ordinary token was read,

 * >0 for special situations (see iscan.h).

 * If the token required a terminating character (i.e., was a name or

 * number) and the next character was whitespace, read and discard

 * that character.  Note that the state is relevant for e_VMerror

 * as well as for scan_Refill.

 */

int

scan_token(i_ctx_t *i_ctx_p, stream * s, ref * pref, scanner_state * pstate)

{

    ref *myref = pref;

    int retcode = 0;

    int c;

    s_declare_inline(s, sptr, endptr);

#define scan_begin_inline() s_begin_inline(s, sptr, endptr)

#define scan_getc() sgetc_inline(s, sptr, endptr)

#define scan_putback() sputback_inline(s, sptr, endptr)

#define scan_end_inline() s_end_inline(s, sptr, endptr)

    const byte *newptr;

    byte *daptr;

#define sreturn(code)\

  { retcode = gs_note_error(code); goto sret; }

#define sreturn_no_error(code)\

  { scan_end_inline(); return(code); }

#define if_not_spush1()\

  if ( osp < ostop ) osp++;\

  else if ( (retcode = ref_stack_push(&o_stack, 1)) >= 0 )\

    ;\

  else

#define spop1()\

  if ( osp >= osbot ) osp--;\

  else ref_stack_pop(&o_stack, 1)

    int max_name_ctype =

    (recognize_btokens()? ctype_name : ctype_btoken);

#define scan_sign(sign, ptr)\

  switch ( *ptr ) {\

    case '-': sign = -1; ptr++; break;\

    case '+': sign = 1; ptr++; break;\

    default: sign = 0;\

  }

#define ensure2_back(styp,nback)\

  if ( sptr >= endptr ) { sptr -= nback; scan_type = styp; goto pause; }

#define ensure2(styp) ensure2_back(styp, 1)

    byte s1[2];

    const byte *const decoder = scan_char_decoder;

    int status;

    int sign;

    const bool check_only = (pstate->s_options & SCAN_CHECK_ONLY) != 0;

    const bool PDFScanRules = (i_ctx_p->scanner_options & SCAN_PDF_RULES) != 0;

    const bool PDFScanInvNum = (i_ctx_p->scanner_options & SCAN_PDF_INV_NUM) != 0;

    scanner_state sstate;

#define pstack sstate.s_pstack

#define pdepth sstate.s_pdepth

#define scan_type sstate.s_scan_type

#define da sstate.s_da

#define name_type sstate.s_ss.s_name.s_name_type

#define try_number sstate.s_ss.s_name.s_try_number

    sptr = endptr = NULL; /* Quiet compiler */

    if (pstate->s_pstack != 0) {

	if_not_spush1()

	    return retcode;

	myref = osp;

    }

    /* Check whether we are resuming after an interruption. */

    if (pstate->s_scan_type != scanning_none) {

	sstate = *pstate;

	if (!da.is_dynamic && da.base != da.buf) {

	    /* The da contains some self-referencing pointers. */

	    /* Fix them up now. */

	    uint next = da.next - da.base;

	    uint limit = da.limit - da.base;

	    da.base = da.buf;

	    da.next = da.buf + next;

	    da.limit = da.buf + limit;

	}

	daptr = da.next;

	switch (scan_type) {

	    case scanning_binary:

		retcode = (*sstate.s_ss.binary.cont)

		    (i_ctx_p, s, myref, &sstate);

		scan_begin_inline();

		if (retcode == scan_Refill)

		    goto pause;

		goto sret;

	    case scanning_comment:

		scan_begin_inline();

		goto cont_comment;

	    case scanning_name:

		goto cont_name;

	    case scanning_string:

		goto cont_string;

	    default:

		return_error(e_Fatal);

	}

    }

    /* Fetch any state variables that are relevant even if */

    /* scan_type == scanning_none. */

    pstack = pstate->s_pstack;

    pdepth = pstate->s_pdepth;

    sstate.s_options = pstate->s_options;

    scan_begin_inline();

    /*

     * Loop invariants:

     *      If pstack != 0, myref = osp, and *osp is a valid slot.

     */

  top:c = scan_getc();

    if_debug1('S', (c >= 32 && c <= 126 ? "`%c'" : c >= 0 ? "`\\%03o'" : "`%d'"), c);

    switch (c) {

	case ' ':

	case '\f':

	case '\t':

	case char_CR:

	case char_EOL:

	case char_NULL:

	    goto top;

        case 0x4:	/* ^D is a self-delimiting token */

	case '[':

	case ']':

	    s1[0] = (byte) c;

	    retcode = name_ref(imemory, s1, 1, myref, 1);	/* can't fail */

	    r_set_attrs(myref, a_executable);

	    break;

	case '<':

	    if (scan_enable_level2) {

		ensure2(scanning_none);

		c = scan_getc();

		switch (c) {

		    case '<':

			scan_putback();

			name_type = 0;

			try_number = false;

			goto try_funny_name;

		    case '~':

			s_A85D_init_inline(&sstate.s_ss.a85d);

			sstate.s_ss.st.template = &s_A85D_template;

			goto str;

		}

		scan_putback();

	    }

	    s_AXD_init_inline(&sstate.s_ss.axd);

	    sstate.s_ss.st.template = &s_AXD_template;

	  str:scan_end_inline();

	    dynamic_init(&da, imemory);

	  cont_string:for (;;) {

		stream_cursor_write w;

		w.ptr = da.next - 1;

		w.limit = da.limit - 1;

		status = (*sstate.s_ss.st.template->process)

		    (&sstate.s_ss.st, &s->cursor.r, &w,

		     s->end_status == EOFC);

		if (!check_only)

		    da.next = w.ptr + 1;

		switch (status) {

		    case 0:

			status = s->end_status;

			if (status < 0) {

			    if (status == EOFC) {

				if (check_only) {

				    retcode = scan_Refill;

				    scan_type = scanning_string;

				    goto suspend;

				} else

				    sreturn(e_syntaxerror);

			    }

			    break;

			}

			s_process_read_buf(s);

			continue;

		    case 1:

			if (!check_only) {

			    retcode = dynamic_grow(&da, da.next, max_string_size);

			    if (retcode == e_VMerror) {

				scan_type = scanning_string;

				goto suspend;

			    } else if (retcode < 0)

				sreturn(retcode);

			}

			continue;

		}

		break;

	    }

	    scan_begin_inline();

	    switch (status) {

		default:

		    /*case ERRC: */

		    sreturn(e_syntaxerror);

		case INTC:

		case CALLC:

		    scan_type = scanning_string;

		    goto pause;

		case EOFC:

		    ;

	    }

	    retcode = dynamic_make_string(i_ctx_p, myref, &da, da.next);

	    if (retcode < 0) {	/* VMerror */

		sputback(s);	/* rescan ) */

		scan_type = scanning_string;

		goto suspend;

	    }

	    break;

	case '(':

	    sstate.s_ss.pssd.from_string =

		((pstate->s_options & SCAN_FROM_STRING) != 0) &&

		!scan_enable_level2;

	    s_PSSD_partially_init_inline(&sstate.s_ss.pssd);

	    sstate.s_ss.st.template = &s_PSSD_template;

	    goto str;

	case '{':

	    if (pstack == 0) {	/* outermost procedure */

		if_not_spush1() {

		    scan_putback();

		    scan_type = scanning_none;

		    goto pause_ret;

		}

		pdepth = ref_stack_count_inline(&o_stack);

	    }

	    make_int(osp, pstack);

	    pstack = ref_stack_count_inline(&o_stack);

	    if_debug3('S', "[S{]d=%d, s=%d->%d\n",

		      pdepth, (int)osp->value.intval, pstack);

	    goto snext;

	case '>':

	    if (scan_enable_level2) {

		ensure2(scanning_none);

		name_type = 0;

		try_number = false;

		goto try_funny_name;

	    }

	    /* falls through */

	case ')':

	    sreturn(e_syntaxerror);

	case '}':

	    if (pstack == 0)

		sreturn(e_syntaxerror);

	    osp--;

	    {

		uint size = ref_stack_count_inline(&o_stack) - pstack;

		ref arr;

		if_debug4('S', "[S}]d=%d, s=%d->%ld, c=%d\n",

			  pdepth, pstack,

			  (pstack == pdepth ? 0 :

			   ref_stack_index(&o_stack, size)->value.intval),

			  size + pstack);

		myref = (pstack == pdepth ? pref : &arr);

		if (check_only) {

		    make_empty_array(myref, 0);

		    ref_stack_pop(&o_stack, size);

		} else if (ref_array_packing.value.boolval) {

		    retcode = make_packed_array(myref, &o_stack, size,

						idmemory, "scanner(packed)");

		    if (retcode < 0) {	/* must be VMerror */

			osp++;

			scan_putback();

			scan_type = scanning_none;

			goto pause_ret;

		    }

		    r_set_attrs(myref, a_executable);

		} else {

		    retcode = ialloc_ref_array(myref,

					       a_executable + a_all, size,

					       "scanner(proc)");

		    if (retcode < 0) {	/* must be VMerror */

			osp++;

			scan_putback();

			scan_type = scanning_none;

			goto pause_ret;

		    }

		    retcode = ref_stack_store(&o_stack, myref, size, 0, 1,

					      false, idmemory, "scanner");

		    if (retcode < 0) {

			ifree_ref_array(myref, "scanner(proc)");

			sreturn(retcode);

		    }

		    ref_stack_pop(&o_stack, size);

		}

		if (pstack == pdepth) {		/* This was the top-level procedure. */

		    spop1();

		    pstack = 0;

		} else {

		    if (osp < osbot)

			ref_stack_pop_block(&o_stack);

		    pstack = osp->value.intval;

		    *osp = arr;

		    goto snext;

		}

	    }

	    break;

	case '/':

	    ensure2(scanning_none);

	    c = scan_getc();

	    if (!PDFScanRules && (c == '/')) {

		name_type = 2;

		c = scan_getc();

	    } else

		name_type = 1;

	    try_number = false;

	    switch (decoder[c]) {

		case ctype_name:

		default:

		    goto do_name;

		case ctype_btoken:

		    if (!recognize_btokens())

			goto do_name;

		    /* otherwise, an empty name */

		case ctype_exception:

		case ctype_space:

		    /*

		     * Amazingly enough, the Adobe implementations don't accept

		     * / or // followed by [, ], <<, or >>, so we do the same.

		     * (Older versions of our code had a ctype_other case here

		     * that handled these specially.)

		     */

		case ctype_other:

		    da.base = da.limit = daptr = 0;

		    da.is_dynamic = false;

		    goto nx;

	    }

	case '%':

	    {			/* Scan as much as possible within the buffer. */

		const byte *base = sptr;

		const byte *end;

		while (++sptr < endptr)		/* stop 1 char early */

		    switch (*sptr) {

			case char_CR:

			    end = sptr;

			    if (sptr[1] == char_EOL)

				sptr++;

			  cend:	/* Check for externally processed comments. */

			    retcode = scan_comment(i_ctx_p, myref, &sstate,

						   base, end, false);

			    if (retcode != 0)

				goto comment;

			    goto top;

			case char_EOL:

			case '\f':

			    end = sptr;

			    goto cend;

		    }

		/*

		 * We got to the end of the buffer while inside a comment.

		 * If there is a possibility that we must pass the comment

		 * to an external procedure, move what we have collected

		 * so far into a private buffer now.

		 */

#define comment_line da.buf

		--sptr;

		comment_line[1] = 0;

		{

		    /* Could be an externally processable comment. */

		    uint len = sptr + 1 - base;

		    if (len > sizeof(comment_line))

			len = sizeof(comment_line);

		    memcpy(comment_line, base, len);

		    daptr = comment_line + len;

		}

		da.base = comment_line;

		da.is_dynamic = false;

	    }

	    /* Enter here to continue scanning a comment. */

	    /* daptr must be set. */

	  cont_comment:for (;;) {

		switch ((c = scan_getc())) {

		    default:

			if (c < 0)

			    switch (c) {

				case INTC:

				case CALLC:

				    da.next = daptr;

				    scan_type = scanning_comment;

				    goto pause;

				case EOFC:

				    /*

				     * One would think that an EOF in a comment

				     * should be a syntax error, but there are

				     * quite a number of files that end that way.

				     */

				    goto end_comment;

				default:

				    sreturn(e_syntaxerror);

			    }

			if (daptr < comment_line + max_comment_line)

			    *daptr++ = c;

			continue;

		    case char_CR:

		    case char_EOL:

		    case '\f':

		      end_comment:

			retcode = scan_comment(i_ctx_p, myref, &sstate,

					       comment_line, daptr, true);

			if (retcode != 0)

			    goto comment;

			goto top;

		}

	    }

#undef comment_line

	    /*NOTREACHED */

	case EOFC:

	    if (pstack != 0) {

		if (check_only)

		    goto pause;

		sreturn(e_syntaxerror);

	    }

	    retcode = scan_EOF;

	    break;

	case ERRC:

	    sreturn(e_ioerror);

	    /* Check for a Level 2 funny name (<< or >>). */

	    /* c is '<' or '>'.  We already did an ensure2. */

	  try_funny_name:

	    {

		int c1 = scan_getc();

		if (c1 == c) {

		    s1[0] = s1[1] = c;

		    name_ref(imemory, s1, 2, myref, 1);	/* can't fail */

		    goto have_name;

		}

		scan_putback();

	    }

	    sreturn(e_syntaxerror);

	    /* Handle separately the names that might be a number. */

	case '0':

	case '1':

	case '2':

	case '3':

	case '4':

	case '5':

	case '6':

	case '7':

	case '8':

	case '9':

	case '.':

	    sign = 0;