Subversion Repositories planix.SVN

/*
 * pdf.c
 * 
 * pdf file support for page
 */

#include <u.h>
#include <libc.h>
#include <draw.h>
#include <event.h>
#include <bio.h>
#include "page.h"

typedef struct PDFInfo  PDFInfo;
struct PDFInfo {
        GSInfo;
        Rectangle *pagebbox;
};

static Image*   pdfdrawpage(Document *d, int page);
static char*    pdfpagename(Document*, int);

char *pdfprolog = 
#include "pdfprolog.c"
        ;

Rectangle
pdfbbox(GSInfo *gs)
{
        char *p;
        char *f[4];
        Rectangle r;
        
        r = Rect(0,0,0,0);
        waitgs(gs);
        gscmd(gs, "/CropBox knownoget {} {[0 0 0 0]} ifelse PAGE==\n");
        p = Brdline(&gs->gsrd, '\n');
        p[Blinelen(&gs->gsrd)-1] ='\0';
        if(p[0] != '[')
                return r;
        if(tokenize(p+1, f, 4) != 4)
                return r;
        r = Rect(atoi(f[0]), atoi(f[1]), atoi(f[2]), atoi(f[3]));
        waitgs(gs);
        return r;
}

Document*
initpdf(Biobuf *b, int argc, char **argv, uchar *buf, int nbuf)
{
        Document *d;
        PDFInfo *pdf;
        char *p;
        char *fn;
        char fdbuf[20];
        int fd;
        int i, npage;
        Rectangle bbox;

        if(argc > 1) {
                fprint(2, "can only view one pdf file at a time\n");
                return nil;
        }

        fprint(2, "reading through pdf...\n");
        if(b == nil){   /* standard input; spool to disk (ouch) */
                fd = spooltodisk(buf, nbuf, &fn);
                sprint(fdbuf, "/fd/%d", fd);
                b = Bopen(fdbuf, OREAD);
                if(b == nil){
                        fprint(2, "cannot open disk spool file\n");
                        wexits("Bopen temp");
                }
        }else
                fn = argv[0];

        /* sanity check */
        Bseek(b, 0, 0);
        if(!(p = Brdline(b, '\n')) && !(p = Brdline(b, '\r'))) {
                fprint(2, "cannot find end of first line\n");
                wexits("initps");
        }
        if(strncmp(p, "%PDF-", 5) != 0) {
                werrstr("not pdf");
                return nil;
        }

        /* setup structures so one free suffices */
        p = emalloc(sizeof(*d) + sizeof(*pdf));
        d = (Document*) p;
        p += sizeof(*d);
        pdf = (PDFInfo*) p;

        d->extra = pdf;
        d->b = b;
        d->drawpage = pdfdrawpage;
        d->pagename = pdfpagename;
        d->fwdonly = 0;

        if(spawngs(pdf, "-dDELAYSAFER") < 0)
                return nil;

        gscmd(pdf, "%s", pdfprolog);
        waitgs(pdf);

        setdim(pdf, Rect(0,0,0,0), ppi, 0);
        gscmd(pdf, "(%s) (r) file { DELAYSAFER { .setsafe } if } stopped pop pdfopen begin\n", fn);
        gscmd(pdf, "pdfpagecount PAGE==\n");
        p = Brdline(&pdf->gsrd, '\n');
        npage = (p != nil? atoi(p): 0);
        if(npage < 1) {
                fprint(2, "no pages?\n");
                return nil;
        }
        d->npage = npage;
        d->docname = argv[0];

        gscmd(pdf, "Trailer\n");
        bbox = pdfbbox(pdf);

        pdf->pagebbox = emalloc(sizeof(Rectangle)*npage);
        for(i=0; i<npage; i++) {
                gscmd(pdf, "%d pdfgetpage\n", i+1);
                pdf->pagebbox[i] = pdfbbox(pdf);
                if(Dx(pdf->pagebbox[i]) <= 0)
                        pdf->pagebbox[i] = bbox;
        }
        return d;
}

static Image*
pdfdrawpage(Document *doc, int page)
{
        PDFInfo *pdf = doc->extra;
        Image *im;

        gscmd(pdf, "%d DoPDFPage\n", page+1);
        im = readimage(display, pdf->gsdfd, 0);
        if(im == nil) {
                fprint(2, "fatal: readimage error %r\n");
                wexits("readimage");
        }
        waitgs(pdf);
        return im;
}

static char*
pdfpagename(Document*, int page)
{
        static char str[15];
        sprint(str, "p %d", page+1);
        return str;
}