gvcdll.c

GSview 4.6 PostScript previewer。Ghostscript在MS-Windows, OS/2 and Unix下的图形化接口

static int GSDLLCALL
gsdll_stdin(void *instance, char *buf, int len)
{
    char mess[MAXSTR];
    sprintf(mess,"stdin callback not supported: %p %d\n", buf, len);
    gs_addmess(mess);
    return 0; /* EOF */
}

static int GSDLLCALL
gsdll_stdout(void *instance, const char *str, int len)
{
#ifndef VIEWONLY
#ifndef UNIX
    if (callback_pstotext(str, len))
	return len;
#endif
#endif
    if (!pending.abort)
	pdf_checktag(str, len);
    gs_addmess_count(str, len);
    return len;
}

static int GSDLLCALL
gsdll_stderr(void *instance, const char *str, int len)
{
    gs_addmess_count(str, len);
    return len;
}
/*********************************************************************/

/* called from gs_process */
int
gs_dll_init(char *devname)
{
char buf[1024];
char *p, *q;
int code;
int depth;
int i, argc;
char **argv;

	/* build options list */
	p = buf;
	buf[0] = '\0';
	buf[1] = '\0';

	/* add include path */
	if (option.gsinclude[0] != '\0') {
	    strcpy(buf, "-I");
	    strcat(buf, option.gsinclude);
	    p += strlen(p)+1;
	    *p = '\0';
	}

	/* add initial device */
	if (devname) {
	    strcpy(p, "-sDEVICE=");
	    p += strlen(p);
	    strcpy(p, devname);
	    p += strlen(p)+1;
	    *p = '\0';
	    /* restrict depth to values supported by Ghostscript */
	    depth = display.planes * display.bitcount;
	    if (depth > 8)
		depth = 24;
	    else if (depth >=8)
		depth = 8;
	    else if (depth >=4)
		depth = 4;
	    else 
		depth = 1;
	    strcpy(p, "-dBitsPerPixel=");
	    p += strlen(p);
	    sprintf(p, "%d", option.depth ? option.depth : depth);
	    p += strlen(p)+1;
	    *p = '\0';
	}
	else {
	    /* no device at all */
	    strcpy(p, "-dNODISPLAY");
	    p += strlen(p)+1;
	    *p = '\0';
	}

	strcpy(p, "-dNOPAUSE");
	p += strlen(p)+1;
	*p = '\0';

        if (gsdll.revision_number > GS_UNSAFE) {
	    /* after selecting the initial device, we need to execute 
	     * .locksafe
	     */
	    strcpy(p, "-dNOSAFER");
	    p += strlen(p)+1;
	    *p = '\0';
	}
	else {
	    if (option.safer) {
		strcpy(p, "-dSAFER");
		p += strlen(p)+1;
		*p = '\0';
	    }
	}

	if (option.alpha_text > 1) {
	    strcpy(p, "-dNOPLATFONTS");
	    p += strlen(p)+1;
	    *p = '\0';
	}

	/* Ghostscript 7.0 won't execute pdfmark for links unless
	 * the device has /pdfmark as a parameter.  This isn't the
	 * case for any device other than pdfwrite, so we need
	 * to force it to procedd pdfmarks.
	 */
	strcpy(p, "-dDOPDFMARKS");
	p += strlen(p)+1;
	*p = '\0';

	if (pending.text) {
	    /* pstotext needs to make some changes to the systemdict */
	    strcpy(p, "-dDELAYBIND");
	    p += strlen(p)+1;
	    *p = '\0';
 	    strcpy(p, "-dWRITESYSTEMDICT");
	    p += strlen(p)+1;
	    *p = '\0';
	    strcpy(p, "-q");
	    p += strlen(p)+1;
	    *p = '\0';
	    /* GS 5.50 incorrectly allows the page size of nullpage */
	    /* device to be changed.  We must disable this. */
	    strcpy(p, "-dFIXEDMEDIA");
	    p += strlen(p)+1;
	    *p = '\0';
	}

	/* add other options */
	/* option.gsother must have options separated by one or more spaces */
	/* quotes may be put around embedded spaces, but are not copied */
	q = option.gsother;
	while ((q = gs_argnext(q, p, FALSE)) != NULL) {
	    p += strlen(p)+1;
	    *p = '\0';
	}

/* convert buf back to argv */
for (argc=1, p=buf; *p; argc++)
	p += strlen(p)+1;
argv = (char **)malloc((argc+2) * sizeof(char *));
argv[0] = option.gsdll;
for (i=1, p=buf; i<=argc; i++) {
    argv[i] = p;
    p+=strlen(p)+1;
}
argv[i] = NULL;

	if (debug & DEBUG_GENERAL) {
	    gs_addmess("Ghostscript options are:\n");
	    for (i=1; i<=argc; i++) {
		gs_addmess("  ");
		gs_addmess(argv[i]);
		gs_addmess("\n");
	    }
	}

	if (gsdll.minst == NULL) {
	    code = gsdll.new_instance(&gsdll.minst, NULL);
	    if (code) {
		sprintf(buf,"gsapi_new_instance returns %d\n", code);
		gs_addmess(buf);
		return code;
	    }
	    if (image.open) {
		if (debug & DEBUG_GENERAL)
		    gs_addmess("Ghostscript didn't close display when it exited.\n");
	    }
	    gsdll.set_stdio(gsdll.minst, gsdll_stdin, gsdll_stdout, gsdll_stderr);
	    gsdll.set_poll(gsdll.minst, gsdll_poll);
	    gsdll.set_display_callback(gsdll.minst, &gsdisplay);
	}
	code = gsdll.init_with_args(gsdll.minst, argc, argv);
free((void *)argv);
	if (code) {
	    sprintf(buf,"gsapi_init_with_args returns %d\n", code);
	    gs_addmess(buf);
	}

/*
	zoom = FALSE;
*/
	display.epsf_clipped = FALSE;
	gsdll.open = TRUE;
	return code;
}

#ifndef UNIX
/******************************************************************/
/* for pstotext */
HMODULE pstotextModule;
FILE *pstotextOutfile;
void *pstotextInstance;
#ifdef __cplusplus
extern "C" {
#endif
PFN_pstotextInit pstotextInit;
PFN_pstotextFilter pstotextFilter;
PFN_pstotextExit pstotextExit;
PFN_pstotextSetCork pstotextSetCork;
#ifdef __cplusplus
}
#endif
char pstotextLine[2048];
int pstotextCount;


#ifndef VIEWONLY
int
callback_pstotext(const char *str, unsigned long count)
{
    if (pstotextInstance) {
	if (debug & DEBUG_GENERAL)
	    gs_addmess_count(str, (int)count);
	if (pstotextOutfile) {
	    char *d, *e;
	    char *pre, *post;
	    int llx, lly, urx, ury;
	    int status;
	    char ch;
	    if (sizeof(pstotextLine) > count + pstotextCount) { 
		memcpy(pstotextLine+pstotextCount, str, (int)count);
		pstotextCount += (int)count;
		pstotextLine[pstotextCount] = '\0';
		/* can't use strchr, because line may include null char */
		e = (char *)memchr(pstotextLine, '\n', pstotextCount);
		while ( e != NULL ) {
		    ch = *(++e);	/* save character after \n */
		    *e = '\0';
		    d = pre = post = (char *)NULL;
		    llx = lly = urx = ury = 0;
		    status = pstotextFilter(pstotextInstance, pstotextLine, 
			&pre, &d, &post,
			&llx, &lly, &urx, &ury);
		    *e = ch;	/* restore character after \n */
		    memmove(pstotextLine, e, (int)(pstotextCount - (e-pstotextLine)));
		    pstotextCount -= (int)(e-pstotextLine);
		    pstotextLine[pstotextCount] = '\0';
		    /* can't use strchr, because line may include null char */
		    e = (char *)memchr(pstotextLine, '\n', pstotextCount);
		    if (status) {
			char buf[MAXSTR];
			sprintf(buf, "\npstotextFilter error %d\n", status);
			gs_addmess(buf);
			return 1;
		    }
		    if (d) {
			if (pre) {
			    if (*pre == ' ')
				pre++;
			    fputs(pre, pstotextOutfile);
			}
		        fprintf(pstotextOutfile, "%d %d %d %d %s\n",
			    llx, lly, urx, ury, d);
			if (post)
			    fputs(post, pstotextOutfile);
		    }
		}
	    }
	    else
		pstotextCount = 0;	/* buffer overflow */
	}
        return 1;
    }
    return 0;
}
#endif

void
gs_error_code(int code)
{
char buf[MAXSTR];
    sprintf(buf, "Ghostscript returns error code %d\n", code);
    gs_addmess(buf);
}

#ifndef VIEWONLY
/* This handles extracting text from PS or PDF file */
int 
gs_process_pstotext(void)
{
int code;
char buf[MAXSTR];
int angle = 0;
int len;
long lsize, ldone;
int pcdone;
int real_orientation;
    if (load_pstotext())
	return 1;
  
    in_pstotext = TRUE;
    if (option.pstotext == IDM_PSTOTEXTCORK - IDM_PSTOTEXTMENU - 1)
        pstotextSetCork(pstotextInstance, TRUE);

    gs_addmess("Extracting text using pstotext...\n");

    /* open output file */
    if ( (pstotextOutfile = gp_open_scratch_file(szScratch, psfile.text_name, "w")) == (FILE *)NULL) {
	gs_addmess("Can't open temporary file for text extraction\n");
        in_pstotext = FALSE;
	unload_pstotext();
	return 1;
    }
    if (debug & DEBUG_GENERAL)
        gs_addmessf("Writing text index to \042%s\042\n", psfile.text_name);

    percent_pending = FALSE;
    percent_done = 0;
    post_img_message(WM_GSWAIT, IDS_WAITTEXT);

    switch(d_orientation(psfile.pagenum)) {
	default:
	case 0:
	    real_orientation = IDM_PORTRAIT;
	    break;
	case 1:
	    real_orientation = IDM_SEASCAPE;
	    break;
	case 2:
	    real_orientation = IDM_UPSIDEDOWN;
	    break;
	case 3:
	    real_orientation = IDM_LANDSCAPE;
	    break;
    }

    if (psfile.ispdf)
	real_orientation = pdf_orientation(psfile.pagenum);

    switch (real_orientation) {
	case IDM_LANDSCAPE:
	    angle = 270;
	    break;
	case IDM_SEASCAPE:
	    angle = 90;
	    break;
	case IDM_PORTRAIT:
	    angle = 0;
	    break;
	case IDM_UPSIDEDOWN:
	    angle = 180;
	    break;
    }

    /* send pstotext prolog to GS */
    if ((angle==270) && (code = send_pstotext_prolog(pstotextModule, 2)) != 0 ) {
	gs_addmess("Error processing rot270 prolog\n");
	gs_error_code(code);
        in_pstotext = FALSE;
	unload_pstotext();
	return code;
    }
    if ((angle==90) && (code = send_pstotext_prolog(pstotextModule, 3)) != 0 ) {
	gs_addmess("Error processing rot90 prolog\n");
	gs_error_code(code);
        in_pstotext = FALSE;
	unload_pstotext();
	return code;
    }

    if ( (code = send_pstotext_prolog(pstotextModule, 1)) != 0 ) {
	gs_addmess("Error processing ocr prolog\n");
	gs_error_code(code);
        in_pstotext = FALSE;
	unload_pstotext();
	return code;
    }

    /* Don't let anyone stuff around with the page size now */
    gs_printf("/setpagedevice { pop } def\n");

    if (option.safer && (gsdll.revision_number > GS_UNSAFE)) {
	d_permitread();
	gs_printf(".locksafe\n");
    }

    if (psfile.ispdf) {
	int i;
	if ( (code = pdf_head()) != 0 ) {
	    gs_addmess("PDF prolog failed\n");
	    gs_error_code(code);
	    in_pstotext = FALSE;
	    unload_pstotext();
	    return code;
	}
	if ( psfile.dsc == (CDSC *)NULL ) {
	    gs_addmess("Couldn't get PDF page count\n");
	    in_pstotext = FALSE;
	    unload_pstotext();
	    return 1;
	}
	if ( (code = d_init1()) != 0) {
	    gs_addmess("Error creating GSview dictionary\n");
	    gs_error_code(code);
	    in_pstotext = FALSE;
	    unload_pstotext();
	    return 1;
	}

	lsize = psfile.dsc->page_count;
	i = 1;
	while (!pending.abort && !pending.unload && i <= (int)psfile.dsc->page_count) {
	    if ( (code = d_pdf_page(i)) != 0 ) {
		gs_error_code(code);
		in_pstotext = FALSE;
		unload_pstotext();
		return code;
	    }
	    pcdone = (int)(i * 100 / lsize);
	    if ((pcdone != percent_done) && !percent_pending) {
		percent_done = pcdone;
		percent_pending = TRUE;
		post_img_message(WM_GSPERCENT, 0);
	    }
	    i++;
	    if (!multithread) {
		/* peek message loop */
		peek_message();
	    }
	    if (pending.now)
		pending.abort = TRUE;	/* user wants to do something else */
	}
	if ((code = pdf_trailer()) != 0) {
	    gs_addmess("Error in PDF trailer\n");
	    gs_error_code(code);
	    in_pstotext = FALSE;
	    unload_pstotext();
	    return code;
	}
    }
    else {
	if (dfreopen() != 0) {
	    gs_addmess("File changed or missing\n");
	    in_pstotext = FALSE;
	    unload_pstotext();
	    return 1;
	}

	/* get file length */
	lsize = gfile_get_length(psfile.file);
	if (lsize <= 0)
	    lsize = 1;
	gfile_seek(psfile.file, 0, gfile_begin);
	ldone = 0;

	/* send document to GS */
	while (!pending.abort && !pending.unload
	    && ((len = gfile_read(psfile.file, buf, sizeof(buf)))!=0)) {
	    code = gs_execute(buf, len);
	    if (code) {
		dfclose();
	        gs_error_code(code);
		in_pstotext = FALSE;
		unload_pstotext();
		unlink(psfile.text_name);
		psfile.text_name[0] = '\0';
		if (pending.abort) {
		    gs_addmess("\n--- Aborted ---\n");
		    return 0;
		}
		else {
		    gs_addmess("\n--- Begin offending input ---\n");
		    gs_addmess_count(buf, len);
		    gs_addmess("\n--- End offending input ---\n");
		    sprintf(buf, "gsapi_run_string_continue returns %d\n", code);
		    gs_addmess(buf);
		}
		return code;
	    }
	    ldone += len;
	    pcdone = (int)(ldone * 100.0 / lsize);
	    if ((pcdone != percent_done) && !percent_pending) {
		percent_done = pcdone;
		percent_pending = TRUE;
		post_img_message(WM_GSPERCENT, 0);
	    }
	    if (!multithread) {
		/* peek message loop */
		peek_message();
	    }
	    if (pending.now)
		pending.abort = TRUE;	/* user wants to do something else */
	}
	dfclose();
    }


    /* close output file */
    fclose(pstotextOutfile);

    /* unload pstotext DLL */
    in_pstotext = FALSE;
    unload_pstotext();

    /* if successful, restart extract or find */
    if (!pending.unload && !pending.abort) {
        gs_addmess("\npstotext successful\n");
	if (psfile.text_extract)
	    post_img_message(WM_COMMAND, IDM_TEXTEXTRACT_SLOW);
	else
	    post_img_message(WM_COMMAND, IDM_TEXTFINDNEXT);
    }
    else {
        gs_addmess("\npstotext aborted\n");
	unlink(psfile.text_name);
	psfile.text_name[0] = '\0';
    }
    pending.abort = TRUE;    /* ignore errors */
    return 0;
}
#endif
#endif /* !VIEWONLY */