From fb3cf89cbbf5ba7a2844f6016a88c6c4429ecda1 Mon Sep 17 00:00:00 2001
From: Vincent Sanders <vince@kyllikki.org>
Date: Sun, 24 Dec 2017 22:32:59 +0000
Subject: decode indirect objects

---
 src/cos_decode.c | 94 +++++++++++++++++++++++++++++++++++++++++---------------
 src/cos_object.c |  1 +
 src/pdf_doc.c    |  2 +-
 3 files changed, 71 insertions(+), 26 deletions(-)

diff --git a/src/cos_decode.c b/src/cos_decode.c
index a1ca318..8873060 100644
--- a/src/cos_decode.c
+++ b/src/cos_decode.c
@@ -396,7 +396,7 @@ cos_decode_list(struct pdf_doc *doc,
         return res;
     }
 
-    printf("found a list\n");
+    //printf("found a list\n");
 
     cosobj = calloc(1, sizeof(struct cos_object));
     if (cosobj == NULL) {
@@ -647,13 +647,12 @@ cos_attempt_decode_reference(struct pdf_doc *doc,
     nspdferror res;
     uint64_t offset;
     uint8_t c;
-    struct cos_object *generation; /* generation object, reused for output */
-    struct cos_reference *nref; /* new reference */
+    struct cos_object *generation; /* generation object */
 
     offset = *offset_out;
 
     res = cos_decode_number(doc, &offset, &generation);
-    if (res != 0) {
+    if (res != NSPDFERROR_OK) {
         /* no error if next token could not be decoded as a number */
         return NSPDFERROR_OK;
     }
@@ -673,36 +672,81 @@ cos_attempt_decode_reference(struct pdf_doc *doc,
     }
 
     /* two int in a row, look for the R */
-    c = DOC_BYTE(doc, offset++);
-    if (c != 'R') {
-        /* no R so not a reference */
-        cos_free_object(generation);
-        return NSPDFERROR_OK;
-    }
+    c = DOC_BYTE(doc, offset);
+    if (c == 'R') {
+        struct cos_reference *nref; /* new reference */
 
-    /* found reference */
+        //printf("found object reference\n");
+        offset ++;
 
-    //printf("found reference\n");
-    doc_skip_ws(doc, &offset);
+        doc_skip_ws(doc, &offset);
 
-    nref = calloc(1, sizeof(struct cos_reference));
-    if (nref == NULL) {
-        /** \todo free objects */
-        return NSPDFERROR_NOMEM; /* memory error */
-    }
+        nref = calloc(1, sizeof(struct cos_reference));
+        if (nref == NULL) {
+            cos_free_object(generation);
+            return NSPDFERROR_NOMEM; /* memory error */
+        }
 
-    nref->id = (*cosobj_out)->u.i;
-    nref->generation = generation->u.i;
+        nref->id = (*cosobj_out)->u.i;
+        nref->generation = generation->u.i;
 
-    cos_free_object(*cosobj_out);
+        /* overwrite input object for output (it has to be an int which has no
+         * allocation to free)
+         */
+        (*cosobj_out)->type = COS_TYPE_REFERENCE;
+        (*cosobj_out)->u.reference = nref;
 
-    generation->type = COS_TYPE_REFERENCE;
-    generation->u.reference = nref;
+        *offset_out = offset;
 
-    *cosobj_out = generation;
+    } else if ((c == 'o') &&
+               (DOC_BYTE(doc, offset + 1) == 'b') &&
+               (DOC_BYTE(doc, offset + 2) == 'j')) {
+        struct cos_object *indirect; /* indirect object */
+        //printf("indirect\n");
+        offset += 3;
 
-    *offset_out = offset;
+        res = doc_skip_ws(doc, &offset);
+        if (res != NSPDFERROR_OK) {
+            cos_free_object(generation);
+            return res;
+        }
+        //printf("decoding\n");
+
+        res = cos_decode_object(doc, &offset, &indirect);
+        if (res != NSPDFERROR_OK) {
+            cos_free_object(generation);
+            return res;
+        }
+        //printf("parsed object type %d\nendobj\n",indirect->type);
+
+        if ((DOC_BYTE(doc, offset    ) != 'e') &&
+            (DOC_BYTE(doc, offset + 1) != 'n') &&
+            (DOC_BYTE(doc, offset + 2) != 'd') &&
+            (DOC_BYTE(doc, offset + 1) != 'o') &&
+            (DOC_BYTE(doc, offset + 2) != 'b') &&
+            (DOC_BYTE(doc, offset + 3) != 'j')) {
+            cos_free_object(indirect);
+            cos_free_object(generation);
+            return NSPDFERROR_SYNTAX;
+        }
+        offset += 6;
+        //printf("skipping\n");
+
+        res = doc_skip_ws(doc, &offset);
+        if (res != NSPDFERROR_OK) {
+            cos_free_object(indirect);
+            cos_free_object(generation);
+            return res;
+        }
+
+        cos_free_object(*cosobj_out);
+
+        *cosobj_out = indirect;
+
+        *offset_out = offset;
+    }
 
+    cos_free_object(generation);
     return NSPDFERROR_OK;
 }
 
diff --git a/src/cos_object.c b/src/cos_object.c
index 3abe7e8..5ec41a9 100644
--- a/src/cos_object.c
+++ b/src/cos_object.c
@@ -59,6 +59,7 @@ nspdferror cos_free_object(struct cos_object *cos_obj)
             aentry = aentry->next;
             free(oaentry);
         }
+        break;
 
     case COS_TYPE_STREAM:
         free(cos_obj->u.stream);
diff --git a/src/pdf_doc.c b/src/pdf_doc.c
index 7bba54f..4a5cad1 100644
--- a/src/pdf_doc.c
+++ b/src/pdf_doc.c
@@ -99,7 +99,7 @@ xref_get_referenced(struct pdf_doc *doc, struct cos_object **cobj_out)
         entry->object = indirect;
     }
 
-    cobj = entry->object;
+    *cobj_out = entry->object;
 
     return NSPDFERROR_OK;
 }
-- 
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