gvloadimage_poppler.c

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/*************************************************************************
 * Copyright (c) 2011 AT&T Intellectual Property 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors: Details at https://graphviz.org
 *************************************************************************/
 
#include "config.h"
 
#include <stdbool.h>
#include <stdlib.h>
#include <sys/stat.h>
 
#include <gvc/gvplugin_loadimage.h>
 
#ifdef HAVE_PANGOCAIRO
#ifdef HAVE_POPPLER
#include <poppler.h>
#include <cairo.h>
 
enum {
    FORMAT_PDF_CAIRO,
};
 
static void gvloadimage_poppler_free(usershape_t *us)
{
    g_object_unref(us->data);
}
 
static PopplerDocument* gvloadimage_poppler_load(GVJ_t * job, usershape_t *us)
{
    PopplerDocument *document = NULL;
    int num_pages;
 
    assert(job);
    assert(us);
    assert(us->name);
 
    if (us->data) {
        if (us->datafree == gvloadimage_poppler_free)
             document = us->data; /* use cached data */
        else {
             us->datafree(us);        /* free incompatible cache data */
             us->data = NULL;
             us->datafree = NULL;
        }
 
    }
 
    if (!document) { /* read file into cache */
        if (!gvusershape_file_access(us))
            return NULL;
        switch (us->type) {
            case FT_PDF: {
 
                char *absolute;
                if (g_path_is_absolute(us->name)) {
                    absolute = g_strdup (us->name);
                } else {
                    char *dir = g_get_current_dir();
                    absolute = g_build_filename(dir, us->name, NULL);
                    free (dir);
                }
 
                GError *error = NULL;
                char *uri = g_filename_to_uri(absolute, NULL, &error);
 
                g_free(absolute);
                if (uri == NULL) {
                    printf("%s\n", error->message);
                    g_error_free(error);
                    return NULL;
                }
 
                document = poppler_document_new_from_file (uri, NULL, &error);
                g_free(uri);
                if (document == NULL) {
                    printf("%s\n", error->message);
                    g_error_free(error);
                    return NULL;
                }
 
                // check page 1 exists
 
                num_pages = poppler_document_get_n_pages (document);
                if (num_pages < 1) {
                    printf("poppler fail: num_pages %d,  must be at least 1", num_pages);
                    return NULL;
                }
                break;
            }
 
            default:
                break;
        }
 
        if (document) {
            us->data = document;
            us->datafree = gvloadimage_poppler_free;
        }
 
        gvusershape_file_release(us);
    }
 
    return document;
}
 
static void gvloadimage_poppler_cairo(GVJ_t * job, usershape_t *us, boxf b, bool filled)
{
    (void)filled;
 
    PopplerDocument* document = gvloadimage_poppler_load(job, us);
    PopplerPage* page;
 
    cairo_t *cr = job->context; /* target context */
    cairo_surface_t *surface;    /* source surface */
 
    if (document) {
    
        // already done this once, so no err checking
        page = poppler_document_get_page (document, 0);
 
        cairo_save(cr);
 
        surface = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, (int)us->w, (int)us->h);
        cairo_surface_reference(surface);
 
        cairo_set_source_surface(cr, surface, 0, 0);
        cairo_translate(cr, b.LL.x, -b.UR.y);
        cairo_scale(cr, (b.UR.x - b.LL.x)/(us->w), (b.UR.y - b.LL.y)/(us->h)); 
        poppler_page_render (page, cr);
        cairo_paint (cr);
 
        cairo_restore(cr);
    }
}
 
static gvloadimage_engine_t engine_cairo = {
    gvloadimage_poppler_cairo
};
#endif
#endif
 
gvplugin_installed_t gvloadimage_poppler_types[] = {
#ifdef HAVE_PANGOCAIRO
#ifdef HAVE_POPPLER
    {FORMAT_PDF_CAIRO, "pdf:cairo", 1, &engine_cairo, NULL},
#endif
#endif
    {0, NULL, 0, NULL, NULL}
};