ref: 800f77dcdb74497de6a64d48069b8c701ab98dff
parent: fdd132556d3330e9557c36c7e5631844d7cddb37
author: Ali Gholami Rudi <ali@rudi.ir>
date: Sun Apr 15 14:54:26 EDT 2018
pdf: recursively import resources from an external PDF
--- a/pdf.c
+++ b/pdf.c
@@ -1,4 +1,4 @@
-/* PDF post processor functions */
+/* PDF post-processor functions */
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
@@ -512,10 +512,10 @@
return src;
}
-/* return a copy of a pdf object; returns a static buffer */
+/* return a copy of a PDF object; returns a static buffer */
static char *pdf_copy(char *pdf, int len, int pos)
{- static char buf[256];
+ static char buf[1 << 12];
int datlen;
pos += pdf_ws(pdf, len, pos);
datlen = pdf_len(pdf, len, pos);
@@ -526,61 +526,153 @@
return buf;
}
-/* return stream length */
-static int pdf_slen(char *pdf, int len, int pos, int slen)
+static void pdf_dictcopy(char *pdf, int len, int pos, struct sbuf *sb);
+
+/* write stream to sb */
+static int pdf_strcopy(char *pdf, int len, int pos, struct sbuf *sb)
{- int old = pos;
+ int slen, val;
+ int beg;
+ if ((val = pdf_dval_val(pdf, len, pos, "/Length")) < 0)
+ return -1;
+ slen = atoi(pdf + val);
+ pos = pos + pdf_len(pdf, len, pos);
pos += pdf_ws(pdf, len, pos);
+ if (pos + slen + 15 > len)
+ return -1;
+ beg = pos;
pos += strlen("stream");if (pdf[pos] == '\r')
pos++;
pos += 1 + slen;
+ if (pdf[pos] == '\r' || pdf[pos] == ' ')
+ pos++;
if (pdf[pos] == '\n')
pos++;
- pos += strlen("endstream");- return pos - old;
+ pos += strlen("endstream") + 1;+ sbuf_mem(sb, pdf + beg, pos - beg);
+ return 0;
}
+/* copy a PDF object and return its new identifier */
+static int pdf_objcopy(char *pdf, int len, int pos)
+{+ int id;
+ if ((pos = pdf_ref(pdf, len, pos)) < 0)
+ return -1;
+ if (pdf_type(pdf, len, pos) == 'd') {+ struct sbuf *sb = sbuf_make();
+ pdf_dictcopy(pdf, len, pos, sb);
+ sbuf_chr(sb, '\n');
+ if (pdf_dval(pdf, len, pos, "/Length") >= 0)
+ pdf_strcopy(pdf, len, pos, sb);
+ id = obj_beg(0);
+ pdfmem(sbuf_buf(sb), sbuf_len(sb));
+ obj_end();
+ sbuf_free(sb);
+ } else {+ id = obj_beg(0);
+ pdfmem(pdf + pos, pdf_len(pdf, len, pos));
+ pdfout("\n");+ obj_end();
+ }
+ return id;
+}
+
+/* copy a PDF dictionary recursively */
+static void pdf_dictcopy(char *pdf, int len, int pos, struct sbuf *sb)
+{+ int i;
+ int key, val, id;
+ sbuf_printf(sb, "<<");
+ for (i = 0; ; i++) {+ if ((key = pdf_dkey(pdf, len, pos, i)) < 0)
+ break;
+ sbuf_printf(sb, " %s", pdf_copy(pdf, len, key));
+ val = pdf_dval(pdf, len, pos, pdf_copy(pdf, len, key));
+ if (pdf_type(pdf, len, val) == 'r') {+ if ((id = pdf_objcopy(pdf, len, val)) >= 0)
+ sbuf_printf(sb, " %d 0 R", id);
+ } else {+ sbuf_printf(sb, " %s", pdf_copy(pdf, len, val));
+ }
+ }
+ sbuf_printf(sb, " >>");
+}
+
+/* copy resources dictionary */
+static void pdf_rescopy(char *pdf, int len, int pos, struct sbuf *sb)
+{+ char *res_fields[] = {"/ProcSet", "/ExtGState", "/ColorSpace",+ "/Pattern", "/Shading", "/Properties", "/Font", "/XObject"};
+ int res, i;
+ sbuf_printf(sb, " /Resources <<\n");
+ for (i = 0; i < LEN(res_fields); i++) {+ if ((res = pdf_dval_val(pdf, len, pos, res_fields[i])) >= 0) {+ if (pdf_type(pdf, len, res) == 'd') {+ sbuf_printf(sb, " %s ", res_fields[i]);
+ pdf_dictcopy(pdf, len, res, sb);
+ sbuf_printf(sb, "\n");
+ } else {+ sbuf_printf(sb, " %s %s\n", res_fields[i],
+ pdf_copy(pdf, len, res));
+ }
+ }
+ }
+ sbuf_printf(sb, " >>\n");
+}
+
static int pdfext(char *pdf, int len)
{ char *cont_fields[] = {"/Filter", "/DecodeParms"};- int trailer = pdf_trailer(pdf, len);
- int root, cont, pages, page1, stream;
+ int trailer, root, cont, pages, page1, res;
int kids_val, page1_val, val;
int xobj_id, length;
int bbox;
+ struct sbuf *sb;
int i;
- root = pdf_dval_obj(pdf, len, trailer, "/Root");
- pages = pdf_dval_obj(pdf, len, root, "/Pages");
- kids_val = pdf_dval_val(pdf, len, pages, "/Kids");
- page1_val = pdf_lval(pdf, len, kids_val, 0);
- page1 = pdf_ref(pdf, len, page1_val);
- cont = pdf_dval_obj(pdf, len, page1, "/Contents");
- val = pdf_dval_val(pdf, len, cont, "/Length");
+ if ((trailer = pdf_trailer(pdf, len)) < 0)
+ return -1;
+ if ((root = pdf_dval_obj(pdf, len, trailer, "/Root")) < 0)
+ return -1;
+ if ((pages = pdf_dval_obj(pdf, len, root, "/Pages")) < 0)
+ return -1;
+ if ((kids_val = pdf_dval_val(pdf, len, pages, "/Kids")) < 0)
+ return -1;
+ if ((page1_val = pdf_lval(pdf, len, kids_val, 0)) < 0)
+ return -1;
+ if ((page1 = pdf_ref(pdf, len, page1_val)) < 0)
+ return -1;
+ if ((cont = pdf_dval_obj(pdf, len, page1, "/Contents")) < 0)
+ return -1;
+ if ((val = pdf_dval_val(pdf, len, cont, "/Length")) < 0)
+ return -1;
+ res = pdf_dval_val(pdf, len, page1, "/Resources");
length = atoi(pdf + val);
bbox = pdf_dval_val(pdf, len, page1, "/MediaBox");
if (bbox < 0)
bbox = pdf_dval_val(pdf, len, pages, "/MediaBox");
- xobj_id = obj_beg(0);
- pdfout("<<\n");- pdfout(" /Type /XObject\n");- pdfout(" /Subtype /Form\n");- pdfout(" /FormType 1\n");+ sb = sbuf_make();
+ sbuf_printf(sb, "<<\n");
+ sbuf_printf(sb, " /Type /XObject\n");
+ sbuf_printf(sb, " /Subtype /Form\n");
+ sbuf_printf(sb, " /FormType 1\n");
if (bbox >= 0)
- pdfout(" /BBox %s\n", pdf_copy(pdf, len, bbox));- pdfout(" /Matrix [1 0 0 1 %s]\n", pdfpos(o_h, o_v));- pdfout(" /Resources << /ProcSet [/PDF] >>\n");- pdfout(" /Length %d\n", length);+ sbuf_printf(sb, " /BBox %s\n", pdf_copy(pdf, len, bbox));
+ sbuf_printf(sb, " /Matrix [1 0 0 1 %s]\n", pdfpos(o_h, o_v));
+ if (res >= 0)
+ pdf_rescopy(pdf, len, res, sb);
+ sbuf_printf(sb, " /Length %d\n", length);
for (i = 0; i < LEN(cont_fields); i++)
if ((val = pdf_dval_val(pdf, len, cont, cont_fields[i])) >= 0)
- pdfout(" %s %s\n", cont_fields[i],+ sbuf_printf(sb, " %s %s\n", cont_fields[i],
pdf_copy(pdf, len, val));
- pdfout(">>\n");- stream = cont + pdf_len(pdf, len, cont);
- stream += pdf_ws(pdf, len, stream);
- pdfmem(pdf + stream, pdf_slen(pdf, len, stream, length));
- pdfout("\n");+ sbuf_printf(sb, ">>\n");
+ pdf_strcopy(pdf, len, cont, sb);
+ xobj_id = obj_beg(0);
+ pdfmem(sbuf_buf(sb), sbuf_len(sb));
obj_end();
+ sbuf_free(sb);
if (xobj_n == xobj_sz) {xobj_sz += 8;
xobj = mextend(xobj, xobj_n, xobj_sz, sizeof(xobj[0]));
--- a/pdfext.c
+++ b/pdfext.c
@@ -132,7 +132,7 @@
pos += 2;
while (pos + 2 < len && (pdf[pos] != '>' || pdf[pos + 1] != '>')) {pos += pdf_ws(pdf, len, pos);
- if (startswith(key, pdf + pos)) {+ if (pdf_len(pdf, len, pos) == strlen(key) && startswith(key, pdf + pos)) {pos += pdf_len(pdf, len, pos);
pos += pdf_ws(pdf, len, pos);
return pos;