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Diffstat (limited to 'source/pdf/pdf-xref.c')
-rw-r--r--source/pdf/pdf-xref.c73
1 files changed, 35 insertions, 38 deletions
diff --git a/source/pdf/pdf-xref.c b/source/pdf/pdf-xref.c
index 6284e70b..acb31c29 100644
--- a/source/pdf/pdf-xref.c
+++ b/source/pdf/pdf-xref.c
@@ -707,12 +707,12 @@ pdf_xref_size_from_old_trailer(fz_context *ctx, pdf_document *doc, pdf_lexbuf *b
fz_read_line(ctx, doc->file, buf->scratch, buf->size);
s = buf->scratch;
- fz_strsep(&s, " "); /* ignore ofs */
+ fz_strsep(&s, " "); /* ignore start */
if (!s)
- fz_throw(ctx, FZ_ERROR_GENERIC, "invalid range marker in xref");
+ fz_throw(ctx, FZ_ERROR_GENERIC, "xref subsection length missing");
len = fz_atoi64(fz_strsep(&s, " "));
if (len < 0)
- fz_throw(ctx, FZ_ERROR_GENERIC, "xref range marker must be positive");
+ fz_throw(ctx, FZ_ERROR_GENERIC, "xref subsection length must be positive");
/* broken pdfs where the section is not on a separate line */
if (s && *s != '\0')
@@ -738,7 +738,7 @@ pdf_xref_size_from_old_trailer(fz_context *ctx, pdf_document *doc, pdf_lexbuf *b
if (len > (int64_t)((INT64_MAX - t) / n))
fz_throw(ctx, FZ_ERROR_GENERIC, "xref has too many entries");
- fz_seek(ctx, doc->file, (int64_t)(t + n * len), SEEK_SET);
+ fz_seek(ctx, doc->file, t + n * len, SEEK_SET);
}
fz_try(ctx)
@@ -772,11 +772,11 @@ pdf_xref_size_from_old_trailer(fz_context *ctx, pdf_document *doc, pdf_lexbuf *b
}
static pdf_xref_entry *
-pdf_xref_find_subsection(fz_context *ctx, pdf_document *doc, int64_t ofs, int len)
+pdf_xref_find_subsection(fz_context *ctx, pdf_document *doc, int64_t start, int len)
{
pdf_xref *xref = &doc->xref_sections[doc->num_xref_sections-1];
pdf_xref_subsec *sub;
- int new_max;
+ int num_objects;
/* Different cases here. Case 1) We might be asking for a
* subsection (or a subset of a subsection) that we already
@@ -788,15 +788,15 @@ pdf_xref_find_subsection(fz_context *ctx, pdf_document *doc, int64_t ofs, int le
/* Sanity check */
for (sub = xref->subsec; sub != NULL; sub = sub->next)
{
- if (ofs >= sub->start && ofs + len <= sub->start + sub->len)
- return &sub->table[ofs-sub->start]; /* Case 1 */
- if (ofs + len > sub->start && ofs <= sub->start + sub->len)
+ if (start >= sub->start && start + len <= sub->start + sub->len)
+ return &sub->table[start-sub->start]; /* Case 1 */
+ if (start + len > sub->start && start <= sub->start + sub->len)
break; /* Case 3 */
}
- new_max = xref->num_objects;
- if (new_max < ofs + len)
- new_max = ofs + len;
+ num_objects = xref->num_objects;
+ if (num_objects < start + len)
+ num_objects = start + len;
if (sub == NULL)
{
@@ -805,7 +805,7 @@ pdf_xref_find_subsection(fz_context *ctx, pdf_document *doc, int64_t ofs, int le
fz_try(ctx)
{
sub->table = fz_calloc(ctx, len, sizeof(pdf_xref_entry));
- sub->start = ofs;
+ sub->start = start;
sub->len = len;
sub->next = xref->subsec;
xref->subsec = sub;
@@ -815,35 +815,32 @@ pdf_xref_find_subsection(fz_context *ctx, pdf_document *doc, int64_t ofs, int le
fz_free(ctx, sub);
fz_rethrow(ctx);
}
- xref->num_objects = new_max;
- if (doc->max_xref_len < new_max)
- extend_xref_index(ctx, doc, new_max);
+ xref->num_objects = num_objects;
+ if (doc->max_xref_len < num_objects)
+ extend_xref_index(ctx, doc, num_objects);
}
else
{
/* Case 3 */
- ensure_solid_xref(ctx, doc, new_max, doc->num_xref_sections-1);
+ ensure_solid_xref(ctx, doc, num_objects, doc->num_xref_sections-1);
xref = &doc->xref_sections[doc->num_xref_sections-1];
sub = xref->subsec;
}
- return &sub->table[ofs-sub->start];
+ return &sub->table[start-sub->start];
}
static pdf_obj *
pdf_read_old_xref(fz_context *ctx, pdf_document *doc, pdf_lexbuf *buf)
{
+ int len, c, xref_len, carried;
fz_stream *file = doc->file;
-
- int64_t ofs;
- int len;
- char *s;
- size_t n;
- pdf_token tok;
- int64_t i;
- int c;
- int xref_len = pdf_xref_size_from_old_trailer(ctx, doc, buf);
pdf_xref_entry *table;
- int carried;
+ int64_t start, i;
+ pdf_token tok;
+ size_t n;
+ char *s;
+
+ xref_len = pdf_xref_size_from_old_trailer(ctx, doc, buf);
fz_skip_space(ctx, doc->file);
if (fz_skip_string(ctx, doc->file, "xref"))
@@ -858,37 +855,37 @@ pdf_read_old_xref(fz_context *ctx, pdf_document *doc, pdf_lexbuf *buf)
fz_read_line(ctx, file, buf->scratch, buf->size);
s = buf->scratch;
- ofs = fz_atoi64(fz_strsep(&s, " "));
+ start = fz_atoi64(fz_strsep(&s, " "));
len = fz_atoi(fz_strsep(&s, " "));
/* broken pdfs where the section is not on a separate line */
if (s && *s != '\0')
{
- fz_warn(ctx, "broken xref section. proceeding anyway.");
+ fz_warn(ctx, "broken xref subsection. proceeding anyway.");
fz_seek(ctx, file, -(2 + (int)strlen(s)), SEEK_CUR);
}
- if (ofs < 0 || ofs > PDF_MAX_OBJECT_NUMBER
+ if (start < 0 || start > PDF_MAX_OBJECT_NUMBER
|| len < 0 || len > PDF_MAX_OBJECT_NUMBER
- || ofs + len - 1 > PDF_MAX_OBJECT_NUMBER)
+ || start + len - 1 > PDF_MAX_OBJECT_NUMBER)
{
fz_throw(ctx, FZ_ERROR_GENERIC, "xref subsection object numbers are out of range");
}
/* broken pdfs where size in trailer undershoots entries in xref sections */
- if (ofs + len > xref_len)
+ if (start + len > xref_len)
{
- fz_warn(ctx, "broken xref section, proceeding anyway.");
+ fz_warn(ctx, "broken xref subsection, proceeding anyway.");
}
- table = pdf_xref_find_subsection(ctx, doc, ofs, len);
+ table = pdf_xref_find_subsection(ctx, doc, start, len);
/* Xref entries SHOULD be 20 bytes long, but we see 19 byte
* ones more frequently than we'd like (e.g. PCLm drivers).
* Cope with this by 'carrying' data forward. */
carried = 0;
- for (i = ofs; i < ofs + len; i++)
+ for (i = 0; i < len; i++)
{
- pdf_xref_entry *entry = &table[i-ofs];
+ pdf_xref_entry *entry = &table[i];
n = fz_read(ctx, file, (unsigned char *) buf->scratch + carried, 20-carried);
if (n != 20-carried)
fz_throw(ctx, FZ_ERROR_GENERIC, "unexpected EOF in xref table");
@@ -903,7 +900,7 @@ pdf_read_old_xref(fz_context *ctx, pdf_document *doc, pdf_lexbuf *buf)
entry->ofs = fz_atoi64(s);
entry->gen = fz_atoi(s + 11);
- entry->num = (int)i;
+ entry->num = start + i;
entry->type = s[17];
if (s[17] != 'f' && s[17] != 'n' && s[17] != 'o')
fz_throw(ctx, FZ_ERROR_GENERIC, "unexpected xref type: 0x%x (%d %d R)", s[17], entry->num, entry->gen);
generated by cgit v1.2.3 (git 2.25.1) at 2025-03-31 21:35:15 +0000