clean up after errors

make error messages more informative

diff --git a/plugin/gs/gvloadimage_gs.c b/plugin/gs/gvloadimage_gs.c
index f1ef79ecff590f0388e82a8ca66d99beadece25b..be8823c035f7681c6992c9ab282328cc4b2d70f6 100644 (file)
--- a/plugin/gs/gvloadimage_gs.c
+++ b/plugin/gs/gvloadimage_gs.c
@@ -50,9 +50,8 @@ static void gvloadimage_gs_free(usershape_t *us)
 {
     gs_t *gs = (gs_t*)us->data;
 
-    cairo_pattern_destroy(gs->pattern);
+    if (gs->pattern) cairo_pattern_destroy(gs->pattern);
     cairo_surface_destroy(gs->surface);
-    cairo_destroy(gs->cr);
     free(gs);
 }
 
@@ -67,8 +66,21 @@ static int gs_writer(void *caller_handle, const char *str, int len)
 
 static void gs_error(GVJ_t * job, const char *funstr, int err)
 {
+    const char *errsrc;
+
     assert (err < 0);
-    job->common->errorfn("%s() returned: %s\n", funstr, gs_error_names[-err - 1]);
+
+    if (err >= e_VMerror) 
+       errsrc = "PostScript Level 1"; 
+    else if (err >= e_unregistered)
+       errsrc = "PostScript Level 2";
+    else if (err >= e_invalidid)
+       errsrc = "DPS error";
+    else
+       errsrc = "Ghostscript internal error";
+
+    job->common->errorfn("%s() returned: %d \"%s\" (%s)\n",
+               funstr, err, gs_error_names[-err - 1], errsrc);
 }
 
 static cairo_pattern_t* gvloadimage_gs_load(GVJ_t * job, usershape_t *us)
@@ -107,18 +119,7 @@ static cairo_pattern_t* gvloadimage_gs_load(GVJ_t * job, usershape_t *us)
            job->common->errorfn("Failure to read shape file\n");
            return NULL;
        }
-       gs = (gs_t *)malloc(sizeof(gs_t));
-       if (!gs) {
-           job->common->errorfn("malloc() failure\n");
-           return NULL;
-       }
-       gs->cr = (cairo_t *)job->context;
-       gs->surface = cairo_surface_create_similar( 
-                       cairo_get_target(gs->cr),
-                       CAIRO_CONTENT_COLOR_ALPHA,
-                       us->x + us->w,
-                       us->y + us->h);
-       gs->pattern = cairo_pattern_create_for_surface (gs->surface);
+
 #define GSAPI_REVISION_REQUIRED 863
        rc = gsapi_revision(&gsapi_revision_info, sizeof(gsapi_revision_t));
         if (rc && rc < sizeof(gsapi_revision_t)) {
@@ -130,42 +131,65 @@ static cairo_pattern_t* gvloadimage_gs_load(GVJ_t * job, usershape_t *us)
                gsapi_revision_info.revision);
            return NULL;
        }
+
        rc = gsapi_new_instance(&instance, (void*)job);
        if (rc) {
            gs_error(job, "gsapi_new_instance", rc);
            return NULL;
        }
+
        rc = gsapi_set_stdio(instance, NULL, gs_writer, gs_writer);
        if (rc) {
            gs_error(job, "gsapi_set_stdio", rc);
            gsapi_delete_instance(instance);
            return NULL;
        }
+
+       gs = (gs_t *)malloc(sizeof(gs_t));
+       if (!gs) {
+           job->common->errorfn("malloc() failure\n");
+           return NULL;
+       }
+       gs->cr = (cairo_t *)job->context;
+       gs->surface = cairo_surface_create_similar( 
+                       cairo_get_target(gs->cr),
+                       CAIRO_CONTENT_COLOR_ALPHA,
+                       us->x + us->w,
+                       us->y + us->h);
+       gs->pattern = cairo_pattern_create_for_surface (gs->surface);
+
        sprintf(width_height, "-g%dx%d", us->x + us->w, us->y + us->h);
        sprintf(dpi, "-r%d", us->dpi);
-       cr = cairo_create(gs->surface);
+       cr = cairo_create(gs->surface);  /* temp context for gs */
        sprintf(cairo_context, "-sCairoContext=%p", cr);
        rc = gsapi_init_with_args(instance, GS_ARGC, gs_args);
-       cairo_destroy(cr);
+       cairo_destroy(cr); /* finished with temp context */
        if (rc) {
            gs_error(job, "gsapi_init_with_args", rc);
+           gsapi_delete_instance(instance);
+           cairo_surface_destroy(gs->surface);
+           cairo_pattern_destroy(gs->pattern);
+           free(gs);
            return NULL;
        }
+
        rc = gsapi_run_file(instance, us->name, -1, &exit_code); 
        if (rc) {
            gs_error(job, "gsapi_run_file", rc);
-           rc = gsapi_exit(instance);
-           if (rc) {
-               gs_error(job, "gsapi_exit", rc);
-               return NULL;
-           }
-           gsapi_delete_instance(instance);
-           return NULL;
+           /* cache the result anyway, so that we don't repeat */
+           cairo_surface_destroy(gs->surface);
+           gs->surface = NULL;
+           cairo_pattern_destroy(gs->pattern);
+           gs->pattern = NULL;
        }
        rc = gsapi_exit(instance);
        if (rc) {
            gs_error(job, "gsapi_exit", rc);
-           return NULL;
+           /* cache the result anyway, so that we don't repeat */
+           cairo_surface_destroy(gs->surface);
+           gs->surface = NULL;
+           cairo_pattern_destroy(gs->pattern);
+           gs->pattern = NULL;
        }
        gsapi_delete_instance(instance);