diff options
Diffstat (limited to 'source/pdf/pdf-write.c')
| -rw-r--r-- | source/pdf/pdf-write.c | 47 |
1 files changed, 36 insertions, 11 deletions
diff --git a/source/pdf/pdf-write.c b/source/pdf/pdf-write.c index 6f5088c6..dc063762 100644 --- a/source/pdf/pdf-write.c +++ b/source/pdf/pdf-write.c @@ -504,13 +504,22 @@ objects_dump(fz_context *ctx, pdf_document *doc, pdf_write_options *opts) * Garbage collect objects not reachable from the trailer. */ -static pdf_obj *sweepref(fz_context *ctx, pdf_document *doc, pdf_write_options *opts, pdf_obj *obj) +/* Mark a reference. If it's been marked already, return NULL (as no further + * processing is required). If it's not, return the resolved object so + * that we can continue our recursive marking. If it's a duff reference + * return the fact so that we can remove the reference at source. + */ +static pdf_obj *markref(fz_context *ctx, pdf_document *doc, pdf_write_options *opts, pdf_obj *obj, int *duff) { int num = pdf_to_num(ctx, obj); int gen = pdf_to_gen(ctx, obj); if (num <= 0 || num >= pdf_xref_len(ctx, doc)) + { + *duff = 1; return NULL; + } + *duff = 0; if (opts->use_list[num]) return NULL; @@ -536,29 +545,47 @@ static pdf_obj *sweepref(fz_context *ctx, pdf_document *doc, pdf_write_options * /* Leave broken */ } - return pdf_resolve_indirect(ctx, obj); + obj = pdf_resolve_indirect(ctx, obj); + if (obj == NULL || pdf_is_null(ctx, obj)) + { + *duff = 1; + opts->use_list[num] = 0; + } + + return obj; } -static void sweepobj(fz_context *ctx, pdf_document *doc, pdf_write_options *opts, pdf_obj *obj) +/* Recursively mark an object. If any references found are duff, then + * replace them with nulls. */ +static int markobj(fz_context *ctx, pdf_document *doc, pdf_write_options *opts, pdf_obj *obj) { int i; if (pdf_is_indirect(ctx, obj)) - obj = sweepref(ctx, doc, opts, obj); + { + int duff; + obj = markref(ctx, doc, opts, obj, &duff); + if (duff) + return 1; + } if (pdf_is_dict(ctx, obj)) { int n = pdf_dict_len(ctx, obj); for (i = 0; i < n; i++) - sweepobj(ctx, doc, opts, pdf_dict_get_val(ctx, obj, i)); + if (markobj(ctx, doc, opts, pdf_dict_get_val(ctx, obj, i))) + pdf_dict_put_val_drop(ctx, obj, i, pdf_new_null(ctx, doc)); } else if (pdf_is_array(ctx, obj)) { int n = pdf_array_len(ctx, obj); for (i = 0; i < n; i++) - sweepobj(ctx, doc, opts, pdf_array_get(ctx, obj, i)); + if (markobj(ctx, doc, opts, pdf_array_get(ctx, obj, i))) + pdf_array_put_drop(ctx, obj, i, pdf_new_null(ctx, doc)); } + + return 0; } /* @@ -2626,8 +2653,8 @@ void pdf_write_document(fz_context *ctx, pdf_document *doc, char *filename, fz_w } /* Sweep & mark objects from the trailer */ - if (opts.do_garbage >= 1) - sweepobj(ctx, doc, &opts, pdf_trailer(ctx, doc)); + if (opts.do_garbage >= 1 || opts.do_linear) + (void)markobj(ctx, doc, &opts, pdf_trailer(ctx, doc)); else for (num = 0; num < xref_len; num++) opts.use_list[num] = 1; @@ -2645,14 +2672,12 @@ void pdf_write_document(fz_context *ctx, pdf_document *doc, char *filename, fz_w renumberobjs(ctx, doc, &opts); /* Truncate the xref after compacting and renumbering */ - if (opts.do_garbage >= 2 && !opts.do_incremental) + if ((opts.do_garbage >= 2 || opts.do_linear) && !opts.do_incremental) while (xref_len > 0 && !opts.use_list[xref_len-1]) xref_len--; if (opts.do_linear) - { linearize(ctx, doc, &opts); - } writeobjects(ctx, doc, &opts, 0); |