Commit 39df5936fea3edd90e1cfeb568098a32510e6a3d

Authored by m-holger
1 parent ed656194

Refactor Xref_table::read_table

Rename to Xref_table::process_section.
Process trailer processing subsection entries.
libqpdf/QPDF.cc
... ... @@ -732,7 +732,7 @@ QPDF::Xref_table::read(qpdf_offset_t xref_offset)
732 732 while (QUtil::is_space(buf[skip])) {
733 733 ++skip;
734 734 }
735   - xref_offset = read_table(xref_offset + skip);
  735 + xref_offset = process_section(xref_offset + skip);
736 736 } else {
737 737 xref_offset = read_stream(xref_offset);
738 738 }
... ... @@ -994,11 +994,32 @@ QPDF::Xref_table::read_entry(qpdf_offset_t& f1, int& f2, char& type)
994 994  
995 995 // Read a single cross-reference table section and associated trailer.
996 996 qpdf_offset_t
997   -QPDF::Xref_table::read_table(qpdf_offset_t xref_offset)
  997 +QPDF::Xref_table::process_section(qpdf_offset_t xref_offset)
998 998 {
999 999 file->seek(xref_offset, SEEK_SET);
1000 1000 std::string line;
1001 1001 auto subs = subsections(line);
  1002 +
  1003 + auto cur_trailer_offset = file->tell();
  1004 + auto cur_trailer = read_trailer();
  1005 + if (!cur_trailer.isDictionary()) {
  1006 + QTC::TC("qpdf", "QPDF missing trailer");
  1007 + throw qpdf.damagedPDF("", "expected trailer dictionary");
  1008 + }
  1009 +
  1010 + if (!trailer_) {
  1011 + trailer_ = cur_trailer;
  1012 +
  1013 + if (!trailer_.hasKey("/Size")) {
  1014 + QTC::TC("qpdf", "QPDF trailer lacks size");
  1015 + throw qpdf.damagedPDF("trailer", "trailer dictionary lacks /Size key");
  1016 + }
  1017 + if (!trailer_.getKey("/Size").isInteger()) {
  1018 + QTC::TC("qpdf", "QPDF trailer size not integer");
  1019 + throw qpdf.damagedPDF("trailer", "/Size key in trailer dictionary is not an integer");
  1020 + }
  1021 + }
  1022 +
1002 1023 for (auto [obj, num, offset]: subs) {
1003 1024 file->seek(offset, SEEK_SET);
1004 1025 for (qpdf_offset_t i = obj; i - num < obj; ++i) {
... ... @@ -1027,26 +1048,6 @@ QPDF::Xref_table::read_table(qpdf_offset_t xref_offset)
1027 1048 }
1028 1049 }
1029 1050  
1030   - // Set offset to previous xref table if any
1031   - auto cur_trailer = read_trailer();
1032   - if (!cur_trailer.isDictionary()) {
1033   - QTC::TC("qpdf", "QPDF missing trailer");
1034   - throw qpdf.damagedPDF("", "expected trailer dictionary");
1035   - }
1036   -
1037   - if (!trailer_) {
1038   - trailer_ = cur_trailer;
1039   -
1040   - if (!trailer_.hasKey("/Size")) {
1041   - QTC::TC("qpdf", "QPDF trailer lacks size");
1042   - throw qpdf.damagedPDF("trailer", "trailer dictionary lacks /Size key");
1043   - }
1044   - if (!trailer_.getKey("/Size").isInteger()) {
1045   - QTC::TC("qpdf", "QPDF trailer size not integer");
1046   - throw qpdf.damagedPDF("trailer", "/Size key in trailer dictionary is not an integer");
1047   - }
1048   - }
1049   -
1050 1051 if (cur_trailer.hasKey("/XRefStm")) {
1051 1052 if (ignore_streams_) {
1052 1053 QTC::TC("qpdf", "QPDF ignoring XRefStm in trailer");
... ... @@ -1056,7 +1057,7 @@ QPDF::Xref_table::read_table(qpdf_offset_t xref_offset)
1056 1057 // /Prev key instead of the xref stream's.
1057 1058 (void)read_stream(cur_trailer.getKey("/XRefStm").getIntValue());
1058 1059 } else {
1059   - throw qpdf.damagedPDF("xref stream", xref_offset, "invalid /XRefStm");
  1060 + throw qpdf.damagedPDF("xref stream", cur_trailer_offset, "invalid /XRefStm");
1060 1061 }
1061 1062 }
1062 1063 }
... ... @@ -1064,7 +1065,8 @@ QPDF::Xref_table::read_table(qpdf_offset_t xref_offset)
1064 1065 if (cur_trailer.hasKey("/Prev")) {
1065 1066 if (!cur_trailer.getKey("/Prev").isInteger()) {
1066 1067 QTC::TC("qpdf", "QPDF trailer prev not integer");
1067   - throw qpdf.damagedPDF("trailer", "/Prev key in trailer dictionary is not an integer");
  1068 + throw qpdf.damagedPDF(
  1069 + "trailer", cur_trailer_offset, "/Prev key in trailer dictionary is not an integer");
1068 1070 }
1069 1071 QTC::TC("qpdf", "QPDF prev key in trailer dictionary");
1070 1072 return cur_trailer.getKey("/Prev").getIntValue();
... ...
libqpdf/qpdf/QPDF_private.hh
... ... @@ -124,7 +124,7 @@ class QPDF::Xref_table
124 124 void read(qpdf_offset_t offset);
125 125  
126 126 // Methods to parse tables
127   - qpdf_offset_t read_table(qpdf_offset_t offset);
  127 + qpdf_offset_t process_section(qpdf_offset_t offset);
128 128 std::vector<Subsection> subsections(std::string& line);
129 129 Subsection subsection(std::string const& line);
130 130 bool read_entry(qpdf_offset_t& f1, int& f2, char& type);
... ...