From 466cb473d1600f6951baf7687e1b62932f41e026 Mon Sep 17 00:00:00 2001
From: Michael R Sweet <msweet@msweet.org>
Date: Thu, 10 Jun 2021 10:58:07 -0400
Subject: [PATCH] Fix _pdfioFileRead/Seek to fix test suite-reported error
 loading an object.

---
 pdfio-common.c | 16 ++++++++++++++++
 pdfio-object.c |  7 +++++++
 pdfio-stream.c |  1 -
 testpdfio.c    |  9 ++++++---
 4 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/pdfio-common.c b/pdfio-common.c
index dcf75b0..02f96d7 100644
--- a/pdfio-common.c
+++ b/pdfio-common.c
@@ -141,6 +141,8 @@ _pdfioFileGets(pdfio_file_t *pdf,	// I - PDF file
 	*bufend = buffer + bufsize - 1;	// Pointer to end of buffer
 
 
+  PDFIO_DEBUG("_pdfioFileGets(pdf=%p, buffer=%p, bufsize=%lu) bufpos=%ld, buffer=%p, bufptr=%p, bufend=%p\n", pdf, buffer, (unsigned long)bufsize, (long)pdf->bufpos, pdf->buffer, pdf->bufptr, pdf->bufend);
+
   while (!eol)
   {
     // If there are characters ready in the buffer, use them...
@@ -180,6 +182,8 @@ _pdfioFileGets(pdfio_file_t *pdf,	// I - PDF file
 
   *bufptr = '\0';
 
+  PDFIO_DEBUG("_pdfioFileGets: Returning %s, '%s'\n", eol ? "true" : "false", buffer);
+
   return (eol);
 }
 
@@ -310,6 +314,13 @@ _pdfioFileRead(pdfio_file_t *pdf,	// I - PDF file
     // Nothing buffered...
     if (bytes > 1024)
     {
+      // Advance current position in file as needed...
+      if (pdf->bufend)
+      {
+	pdf->bufpos += pdf->bufend - pdf->buffer;
+	pdf->bufptr = pdf->bufend = NULL;
+      }
+
       // Read directly from the file...
       if ((rbytes = read_buffer(pdf, bufptr, bytes)) > 0)
       {
@@ -356,6 +367,8 @@ _pdfioFileSeek(pdfio_file_t *pdf,	// I - PDF file
     {
       // Yes, seek within existing buffer...
       pdf->bufptr = pdf->buffer + offset - pdf->bufpos;
+      PDFIO_DEBUG("_pdfioFileSeek: Seek within buffer, bufpos=%ld.\n", (long)pdf->bufpos);
+      PDFIO_DEBUG("_pdfioFileSeek: buffer=%p, bufptr=%p, bufend=%p\n", pdf->buffer, pdf->bufptr, pdf->bufend);
       return (offset);
     }
 
@@ -381,6 +394,9 @@ _pdfioFileSeek(pdfio_file_t *pdf,	// I - PDF file
     return (-1);
   }
 
+  PDFIO_DEBUG("_pdfioFileSeek: Reset bufpos=%ld.\n", (long)pdf->bufpos);
+  PDFIO_DEBUG("_pdfioFileSeek: buffer=%p, bufptr=%p, bufend=%p\n", pdf->buffer, pdf->bufptr, pdf->bufend);
+
   pdf->bufpos = offset;
 
   return (offset);
diff --git a/pdfio-object.c b/pdfio-object.c
index 8ce8210..c8b26bf 100644
--- a/pdfio-object.c
+++ b/pdfio-object.c
@@ -360,6 +360,8 @@ _pdfioObjLoad(pdfio_obj_t *obj)		// I - Object
     return (false);
   }
 
+  PDFIO_DEBUG("_pdfioObjLoad: Header is '%s'.\n", line);
+
   if (strtoimax(line, &ptr, 10) != (intmax_t)obj->number)
   {
     _pdfioFileError(obj->pdf, "Bad header for object %lu.", (unsigned long)obj->number);
@@ -403,8 +405,13 @@ _pdfioObjLoad(pdfio_obj_t *obj)		// I - Object
   {
     // Yes, save its location...
     obj->stream_offset = _pdfioFileTell(obj->pdf);
+    PDFIO_DEBUG("_pdfioObjLoad: stream_offset=%lu.\n", (unsigned long)obj->stream_offset);
   }
 
+  PDFIO_DEBUG("_pdfioObjLoad: ");
+  PDFIO_DEBUG_VALUE(&obj->value);
+  PDFIO_DEBUG("\n");
+
   return (true);
 }
 
diff --git a/pdfio-stream.c b/pdfio-stream.c
index e241417..f9624dc 100644
--- a/pdfio-stream.c
+++ b/pdfio-stream.c
@@ -216,7 +216,6 @@ _pdfioStreamCreate(
       if (predictor >= 10)
 	st->pbsize ++;		// Add PNG predictor byte
 
-      fprintf(stderr, "colors=%d, bpc=%d, pbpixel=%u\n", colors, bpc, (unsigned)st->pbpixel);
       if ((st->prbuffer = calloc(1, st->pbsize - 1)) == NULL || (st->psbuffer = calloc(1, st->pbsize)) == NULL)
       {
 	_pdfioFileError(st->pdf, "Unable to allocate %lu bytes for Predictor buffers.", (unsigned long)st->pbsize);
diff --git a/testpdfio.c b/testpdfio.c
index f72e057..c694ca3 100644
--- a/testpdfio.c
+++ b/testpdfio.c
@@ -274,7 +274,7 @@ do_unit_tests(void)
     return (1);
 
   // Write a page with test images...
-  first_image = pdfioFileGetNumObjs(outpdf);
+  first_image = pdfioFileGetNumObjs(outpdf) + 1;
   if (write_images(outpdf, 7, helvetica))
     return (1);
 
@@ -328,7 +328,10 @@ do_unit_tests(void)
 
   // Verify the images
   for (i = 0; i < 7; i ++)
-    verify_image(pdf, first_image + (size_t)i);
+  {
+    if (verify_image(pdf, first_image + (size_t)i))
+      return (1);
+  }
 
   // Close the new PDF file...
   fputs("pdfioFileClose(\"testpdfio-out.pdf\"): ", stdout);
@@ -401,7 +404,7 @@ draw_image(pdfio_stream_t *st,
 static bool				// O  - `true` to stop, `false` to continue
 error_cb(pdfio_file_t *pdf,		// I  - PDF file
          const char   *message,		// I  - Error message
-	 bool         *error)		// IO - Have we displayed an error? 
+	 bool         *error)		// IO - Have we displayed an error?
 {
   (void)pdf;