cpdf-source/cpdfbookmarks.ml

397 lines
16 KiB
OCaml

open Pdfutil
open Cpdferror
(* Verify a list of bookmarks. Positive jumps of > 1 not allowed, no numbers
smaller than 0. *)
let rec verify_bookmarks pdf lastlevel fastrefnums endpage = function
| [] -> true
| {Pdfmarks.level = level; Pdfmarks.target = target}::more ->
let page = Pdfpage.pagenumber_of_target pdf ~fastrefnums target in
level < lastlevel + 2 &&
level >= 0 &&
page <= endpage &&
page >= 0 &&
verify_bookmarks pdf level fastrefnums endpage more
let verify_bookmarks pdf lastlevel endpage marks =
let refnums = Pdf.page_reference_numbers pdf in
let fastrefnums = hashtable_of_dictionary (combine refnums (indx refnums)) in
match marks with
| [] -> true
| m::more -> m.Pdfmarks.level = 0 && verify_bookmarks pdf lastlevel fastrefnums endpage more
(* Parse a line of the bookmarks file. *)
(* Un-escape things which are escaped. Quotes, newlines and backslashes *)
let rec fixup_characters prev = function
| [] -> rev prev
| '\\'::'\\'::t -> fixup_characters ('\\'::prev) t
| '\\'::'"'::t -> fixup_characters ('"'::prev) t
| '\\'::'n'::t -> fixup_characters ('\n'::prev) t
| h::t -> fixup_characters (h::prev) t
(* If optionaldest = [Pdfgenlex.LexString s], we parse the string, convert the
* integer to an indirect of the real page target, and then put it in. *)
let target_of_markfile_obj pdf i' pdfobj =
(*Printf.printf "Parsed %s\n" (Pdfwrite.string_of_pdf pdfobj);*)
match pdfobj with
Pdf.Array (Pdf.Integer x::more) ->
let pageobjnum = Pdfpage.page_object_number pdf i' in
begin match pageobjnum with
None ->
raise (Pdf.PDFError "bookmark_of_data: page obj num not found")
| Some p ->
Pdfdest.read_destination pdf (Pdf.Array (Pdf.Indirect p::more))
end
(* Need to deal with "null", "(string)", and "<<other thing like action" *)
| Pdf.Null -> Pdfdest.NullDestination
| Pdf.String s -> Pdfdest.read_destination pdf (Pdf.String s)
| x -> Pdfdest.Action x
let target_of_markfile_target pdf i' = function
| [Pdfgenlex.LexString s] ->
let pdfobj = Pdfread.parse_single_object s in
target_of_markfile_obj pdf i' pdfobj
| _ -> Pdfpage.target_of_pagenumber pdf i'
let bookmark_of_data pdf i s i' isopen optionaldest =
{Pdfmarks.level = i;
Pdfmarks.text = Pdftext.pdfdocstring_of_utf8 (implode (fixup_characters [] (explode s)));
Pdfmarks.target = target_of_markfile_target pdf i' optionaldest;
Pdfmarks.isopen = isopen}
let target_of_json_target pdf pagenumber target =
target_of_markfile_obj pdf pagenumber (Cpdfjson.object_of_json target)
let mark_of_json pdf = function
| `Assoc [("level", `Int level);
("text", `String text);
("page", `Int pagenumber);
("open", `Bool openstatus);
("target", target)] ->
{Pdfmarks.level = level;
Pdfmarks.text = Pdftext.pdfdocstring_of_utf8 text;
Pdfmarks.target = target_of_json_target pdf pagenumber target;
Pdfmarks.isopen = openstatus}
| _ -> error "malformed mark in mark_of_json"
let marks_of_json pdf = function
| `List ms -> map (mark_of_json pdf) ms
| _ -> error "top level of JSON boomark file not a list"
let parse_bookmark_file_json verify pdf i =
let module J = Cpdfyojson.Safe in
try
let json =
match i.Pdfio.caml_channel with
| Some ch -> J.from_channel ch
| None ->
let content = Pdfio.string_of_input i in
J.from_string content
in
let marks = marks_of_json pdf json in
if verify then
if verify_bookmarks pdf 0 (Pdfpage.endpage pdf) marks then marks else
error "Bad bookmark file (References non-existant pages or is malformed)"
else
marks
with
e ->
error (Printf.sprintf "Malformed JSON bookmark file (%s)" (Printexc.to_string e))
let parse_bookmark_file verify pdf input =
let currline = ref 0 in
try
let lines = Pdfio.read_lines input in
let currline = ref 0 in
let bookmarks = ref [] in
iter
(function line ->
match
incr currline;
Pdfgenlex.lex_string line
with
| Pdfgenlex.LexInt i::Pdfgenlex.LexString s::Pdfgenlex.LexInt i'::Pdfgenlex.LexName "open"::optionaldest ->
bookmarks =| bookmark_of_data pdf i s i' true optionaldest
| Pdfgenlex.LexInt i::Pdfgenlex.LexString s::Pdfgenlex.LexInt i'::optionaldest ->
bookmarks =| bookmark_of_data pdf i s i' false optionaldest
| [] -> () (* ignore blank lines *)
| _ ->
error ("Bad bookmark file, line " ^ (string_of_int !currline)))
lines;
let bookmarks = rev !bookmarks in
if verify then
if verify_bookmarks pdf 0 (Pdfpage.endpage pdf) bookmarks
then bookmarks
else
error
"Bad bookmark file (References non-existant pages or is malformed)"
else
bookmarks
with
e ->
error
(Printf.sprintf
"Bad bookmark file (syntax) at line %i (error was %s)"
!currline
(Printexc.to_string e))
let add_bookmarks ~json verify input pdf =
let parsed =
(if json then parse_bookmark_file_json else parse_bookmark_file) verify pdf input in
(*iter (fun b -> flprint (Pdfmarks.string_of_bookmark b); flprint "\n") parsed;*)
Pdfmarks.add_bookmarks parsed pdf
(* List bookmarks *)
let output_string_of_target pdf fastrefnums x =
match Pdfdest.pdfobject_of_destination x with
| Pdf.Array (_::more) ->
let a =
Pdf.Array (Pdf.Integer (Pdfpage.pagenumber_of_target ~fastrefnums pdf x)::more)
in
"\"" ^ Pdfwrite.string_of_pdf a ^ "\""
| x -> "\"" ^ Pdfwrite.string_of_pdf x ^ "\""
let json_of_target pdf fastrefnums x =
match Pdfdest.pdfobject_of_destination x with
| Pdf.Array (_::more) ->
let a =
Pdf.Array (Pdf.Integer (Pdfpage.pagenumber_of_target ~fastrefnums pdf x)::more)
in
Cpdfjson.json_of_object pdf (fun _ -> ()) ~utf8:false ~no_stream_data:false ~parse_content:false a
| x -> Cpdfjson.json_of_object pdf (fun _ -> ()) ~utf8:false ~no_stream_data:false ~parse_content:false x
let output_json_marks output calculate_page_number pdf fastrefnums marks =
let module J = Cpdfyojson.Safe in
let json_of_mark m =
`Assoc
[("level", `Int m.Pdfmarks.level);
("text", `String (Pdftext.utf8_of_pdfdocstring (Pdftext.simplify_utf16be m.Pdfmarks.text)));
("page", `Int (calculate_page_number m));
("open", `Bool m.Pdfmarks.isopen);
("target", json_of_target pdf fastrefnums m.Pdfmarks.target)]
in
let json = `List (map json_of_mark marks) in
output.Pdfio.output_string (J.pretty_to_string json)
let process_string encoding s =
let rec replace c x y = function
| [] -> []
| h::t when h = c -> x::y::replace c x y t
| h::t -> h::replace c x y t
in
(* Convert to UTF8, raw, or stripped, and escape backslashed and quotation marks *)
let codepoints = Pdftext.codepoints_of_pdfdocstring s in
let escaped =
let bs = int_of_char '\\'
and nl = int_of_char '\n'
and n = int_of_char 'n'
and q = int_of_char '\"' in
replace q bs q (replace nl bs n (replace bs bs bs codepoints))
in
let process_stripped escaped =
let b = Buffer.create 200 in
iter
(fun x ->
if x <= 127 then Buffer.add_char b (char_of_int x))
escaped;
Buffer.contents b
in
match encoding with
| Cpdfmetadata.UTF8 -> Pdftext.utf8_of_codepoints escaped
| Cpdfmetadata.Stripped -> process_stripped escaped
| Cpdfmetadata.Raw -> s
(* List the bookmarks in the given range to the given output *)
let list_bookmarks ~json encoding range pdf output =
let bookmarks = Pdfmarks.read_bookmarks pdf in
let refnums = Pdf.page_reference_numbers pdf in
let rangetable = hashset_of_list range in
let range_is_all = range = ilist 1 (Pdfpage.endpage pdf) in
let fastrefnums = hashtable_of_dictionary (combine refnums (indx refnums)) in
(* Find the pagenumber of each bookmark target. If it is in the range,
* keep that bookmark. Also keep the bookmark if its target is the null
* destination. *)
let inrange =
keep
(function x ->
range_is_all ||
x.Pdfmarks.target = Pdfdest.NullDestination ||
(match x.Pdfmarks.target with Pdfdest.NamedDestinationElsewhere _ -> true | _ -> false) ||
Hashtbl.mem rangetable (Pdfpage.pagenumber_of_target ~fastrefnums pdf x.Pdfmarks.target)) bookmarks
in
let calculate_page_number mark =
(* Some buggy PDFs use integers for page numbers instead of page
* object references. Adobe Reader and Preview seem to support
* this, for presumably historical reasons. So if we see a
* OtherDocPageNumber (which is what Pdfdest parses these as,
* because that's what they are legitimately, we use this as the
* page number. It is zero based, though, and we are one-based, so
* we add one. Pdfpage.pagenumber_of_target has been modified to support this.*)
Pdfpage.pagenumber_of_target ~fastrefnums pdf mark.Pdfmarks.target
in
if json then
output_json_marks output calculate_page_number pdf fastrefnums inrange
else
iter
(function mark ->
output.Pdfio.output_string
(Printf.sprintf "%i \"%s\" %i%s %s\n"
mark.Pdfmarks.level
(process_string encoding mark.Pdfmarks.text)
(calculate_page_number mark)
(if mark.Pdfmarks.isopen then " open" else "")
(output_string_of_target pdf fastrefnums mark.Pdfmarks.target)))
inrange
let get_bookmarks_json pdf =
let o, br = Pdfio.input_output_of_bytes (20 * 1024) in
list_bookmarks ~json:true Cpdfmetadata.UTF8 (ilist 1 (Pdfpage.endpage pdf)) pdf o;
Pdfio.extract_bytes_from_input_output o br
let get_bookmark_name encoding pdf marks splitlevel n _ =
let refnums = Pdf.page_reference_numbers pdf in
let fastrefnums = hashtable_of_dictionary (combine refnums (indx refnums)) in
match keep (function m -> n = Pdfpage.pagenumber_of_target ~fastrefnums pdf m.Pdfmarks.target && m.Pdfmarks.level <= splitlevel) marks with
| {Pdfmarks.text = title}::_ -> Cpdfattach.remove_unsafe_characters encoding title
| _ -> ""
(* @F means filename without extension *)
(* @N means sequence number with no padding *)
(* @S means start page of this section *)
(* @E means end page of this section *)
(* @B means bookmark name at start page *)
(* @b52| means bookmark name at start page truncated to 52 characters using crude UTF8 truncation. *)
let process_others encoding marks pdf splitlevel filename sequence startpage endpage s =
let trim_utf8 len l =
(* This truncator is far from perfect, but it does yield a valid UTF8 string, when given one. *)
match rev l with
| b2::b1::b0::t ->
if int_of_char b2 land 0x80 > 0 then
begin
if int_of_char b2 land 0x40 > 0 then rev (b1::b0::t)
else if int_of_char b1 land 0xe0 = 0xe0 then rev (b0::t)
else if int_of_char b0 land 0xf0 = 0xf0 then rev t
else l
end
else
l
| _ -> l
in
let rec find_ats p = function
'@'::r -> find_ats (p + 1) r
| r -> (p, r)
in
let string_of_int_width w i =
if w < 0 then raise (Pdf.PDFError "width of field too narrow")
else if w > 8 then raise (Pdf.PDFError "width of field too broad") else
let formats =
[|format_of_string "%i";
format_of_string "%i";
format_of_string "%02i";
format_of_string "%03i";
format_of_string "%04i";
format_of_string "%05i";
format_of_string "%06i";
format_of_string "%07i";
format_of_string "%08i"|]
in
Printf.sprintf formats.(w) i
in
let rec procss prev = function
| [] -> rev prev
| '@'::'F'::t -> procss (rev (explode filename) @ prev) t
| '@'::'N'::t ->
let width, rest = find_ats 0 t in
procss (rev (explode (string_of_int_width width sequence)) @ prev) rest
| '@'::'S'::t ->
let width, rest = find_ats 0 t in
procss (rev (explode (string_of_int_width width startpage)) @ prev) rest
| '@'::'E'::t ->
let width, rest = find_ats 0 t in
procss (rev (explode (string_of_int_width width endpage)) @ prev) rest
| '@'::'B'::t -> procss (rev (explode (get_bookmark_name encoding pdf marks splitlevel startpage pdf)) @ prev) t
| '@'::'b'::t ->
let number, rest = cleavewhile (function '0'..'9' -> true | _ -> false) t in
let text = trim_utf8 (int_of_string (implode number)) (explode (get_bookmark_name encoding pdf marks splitlevel startpage pdf)) in
procss ((rev text) @ prev) (tl rest)
| h::t -> procss (h::prev) t
in
implode (procss [] (explode s))
let name_of_spec encoding marks (pdf : Pdf.t) splitlevel spec n filename startpage endpage =
let fill l n =
let chars = explode (string_of_int n) in
if length chars > l
then implode (drop chars (length chars - l))
else implode ((many '0' (l - length chars)) @ chars)
in
let chars = explode spec in
let before, including = cleavewhile (neq '%') chars in
let percents, after = cleavewhile (eq '%') including in
if percents = []
then
process_others encoding marks pdf splitlevel filename n startpage endpage spec
else
process_others encoding marks pdf splitlevel filename n startpage endpage
(implode before ^ fill (length percents) n ^ implode after)
(* Indent bookmarks in each file by one and add a title bookmark pointing to the first page. *)
let add_bookmark_title filename use_title pdf =
let title =
if use_title then
match Cpdfmetadata.get_info_utf8 pdf "/Title", Cpdfmetadata.get_xmp_info pdf "/Title" with
"", x | x, "" | _, x -> x
else
Filename.basename filename
in
let marks = Pdfmarks.read_bookmarks pdf in
let page1objnum =
match Pdfpage.page_object_number pdf 1 with
None -> error "add_bookmark_title: page not found"
| Some x -> x
in
let newmarks =
{Pdfmarks.level = 0;
Pdfmarks.text = Pdftext.pdfdocstring_of_utf8 title;
Pdfmarks.target = Pdfdest.XYZ (Pdfdest.PageObject page1objnum, None, None, None);
Pdfmarks.isopen = false}
::map (function m -> {m with Pdfmarks.level = m.Pdfmarks.level + 1}) marks
in
Pdfmarks.add_bookmarks newmarks pdf
let bookmarks_open_to_level n pdf =
let marks = Pdfmarks.read_bookmarks pdf in
let newmarks =
map
(fun m -> {m with Pdfmarks.isopen = m.Pdfmarks.level < n})
marks
in
Pdfmarks.add_bookmarks newmarks pdf
(* Alter bookmark destinations given a hash table of (old page reference
* number, new page reference number) pairings *)
let change_destination t = function
Pdfdest.XYZ (Pdfdest.PageObject p, a, b, c) ->
Pdfdest.XYZ (Pdfdest.PageObject (Hashtbl.find t p), a, b, c)
| Pdfdest.Fit (Pdfdest.PageObject p) ->
Pdfdest.Fit (Pdfdest.PageObject (Hashtbl.find t p))
| Pdfdest.FitH (Pdfdest.PageObject p, x) ->
Pdfdest.FitH (Pdfdest.PageObject (Hashtbl.find t p), x)
| Pdfdest.FitV (Pdfdest.PageObject p, x) ->
Pdfdest.FitV (Pdfdest.PageObject (Hashtbl.find t p), x)
| Pdfdest.FitR (Pdfdest.PageObject p, a, b, c, d) ->
Pdfdest.FitR (Pdfdest.PageObject (Hashtbl.find t p), a, b, c, d)
| Pdfdest.FitB (Pdfdest.PageObject p) ->
Pdfdest.Fit (Pdfdest.PageObject (Hashtbl.find t p))
| Pdfdest.FitBH (Pdfdest.PageObject p, x) ->
Pdfdest.FitBH (Pdfdest.PageObject (Hashtbl.find t p), x)
| Pdfdest.FitBV (Pdfdest.PageObject p, x) ->
Pdfdest.FitBV (Pdfdest.PageObject (Hashtbl.find t p), x)
| x -> x
let change_bookmark t m =
{m with Pdfmarks.target =
try change_destination t m.Pdfmarks.target with Not_found -> m.Pdfmarks.target}