Revert "Return pdfium::span<char> from ByteString::GetBuffer()."

This reverts commit 80a6cbe0a427e155de8555bc867af745d10f9777.
Reason for revert: too many abrts in beta branch.

TBR: dsinclair@chromium.org
Bug: 832557, 832978, 832992, 833062, 833097
Change-Id: I7d511dbb224ddc644be96ea2f3770ad6f73debf5
Reviewed-on: https://pdfium-review.googlesource.com/30792
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 22 insertions, 28 deletions

diff --git a/core/fpdfapi/parser/fpdf_parser_utility.cpp b/core/fpdfapi/parser/fpdf_parser_utility.cpp
index b6b94aa84e..c486a76706 100644
--- a/core/fpdfapi/parser/fpdf_parser_utility.cpp
+++ b/core/fpdfapi/parser/fpdf_parser_utility.cpp
@@ -93,23 +93,20 @@ ByteString PDF_NameDecode(const ByteStringView& bstr) {
   if (!bstr.Contains('#'))
     return ByteString(bstr);
 
-  size_t src_size = bstr.GetLength();
-  size_t out_index = 0;
+  int size = bstr.GetLength();
   ByteString result;
-  {
-    // Span's lifetime must end before ReleaseBuffer() below.
-    pdfium::span<char> pDest = result.GetBuffer(src_size);
-    for (size_t i = 0; i < src_size; i++) {
-      if (bstr[i] == '#' && i < src_size - 2) {
-        pDest[out_index++] = FXSYS_HexCharToInt(bstr[i + 1]) * 16 +
-                             FXSYS_HexCharToInt(bstr[i + 2]);
-        i += 2;
-      } else {
-        pDest[out_index++] = bstr[i];
-      }
+  char* pDestStart = result.GetBuffer(size);
+  char* pDest = pDestStart;
+  for (int i = 0; i < size; i++) {
+    if (bstr[i] == '#' && i < size - 2) {
+      *pDest++ = FXSYS_HexCharToInt(bstr[i + 1]) * 16 +
+                 FXSYS_HexCharToInt(bstr[i + 2]);
+      i += 2;
+    } else {
+      *pDest++ = bstr[i];
     }
   }
-  result.ReleaseBuffer(out_index);
+  result.ReleaseBuffer(static_cast<size_t>(pDest - pDestStart));
   return result;
 }
 
@@ -131,23 +128,20 @@ ByteString PDF_NameEncode(const ByteString& orig) {
     return orig;
 
   ByteString res;
-  {
-    // Span's lifetime must end before ReleaseBuffer() below.
-    pdfium::span<char> dest_buf = res.GetBuffer(dest_len);
-    dest_len = 0;
-    for (i = 0; i < src_len; i++) {
-      uint8_t ch = src_buf[i];
-      if (ch >= 0x80 || PDFCharIsWhitespace(ch) || ch == '#' ||
-          PDFCharIsDelimiter(ch)) {
-        dest_buf[dest_len++] = '#';
-        FXSYS_IntToTwoHexChars(ch, &dest_buf[dest_len]);
-        dest_len += 2;
-        continue;
-      }
+  char* dest_buf = res.GetBuffer(dest_len);
+  dest_len = 0;
+  for (i = 0; i < src_len; i++) {
+    uint8_t ch = src_buf[i];
+    if (ch >= 0x80 || PDFCharIsWhitespace(ch) || ch == '#' ||
+        PDFCharIsDelimiter(ch)) {
+      dest_buf[dest_len++] = '#';
+      FXSYS_IntToTwoHexChars(ch, dest_buf + dest_len);
+      dest_len += 2;
+    } else {
       dest_buf[dest_len++] = ch;
     }
-    dest_buf[dest_len] = 0;
   }
+  dest_buf[dest_len] = 0;
   res.ReleaseBuffer(res.GetStringLength());
   return res;
 }