[gnumeric] Fix large strings export. [715110#]

[Jean Bréfort <jbrefort src gnome org>]

commit 9b82bf83fe676f8c6c998d94859f31b2b6284cfd
Author: Jean Brefort <jean brefort normalesup org>
Date:   Tue Nov 26 21:05:14 2013 +0100

    Fix large strings export. [715110#]

 plugins/excel/ChangeLog        |    5 ++++
 plugins/excel/ms-excel-write.c |   48 ++++++++++++++++++++++++++++++++-------
 2 files changed, 44 insertions(+), 9 deletions(-)
---
diff --git a/plugins/excel/ChangeLog b/plugins/excel/ChangeLog
index 0a5ed66..b667ed0 100644
--- a/plugins/excel/ChangeLog
+++ b/plugins/excel/ChangeLog
@@ -1,3 +1,8 @@
+2013-11-26  Jean Brefort  <jean brefort normalesup org>
+
+       * ms-excel-write.c (excel_write_string): fix large strings export. [715110#]
+       (excel_write_ClientTextbox): fix test.
+
 2013-11-25  Morten Welinder  <terra gnome org>
 
        * ms-excel-write.c (excel_write_string): Fix buffer allocation.
diff --git a/plugins/excel/ms-excel-write.c b/plugins/excel/ms-excel-write.c
index 68ebd00..1d4595f 100644
--- a/plugins/excel/ms-excel-write.c
+++ b/plugins/excel/ms-excel-write.c
@@ -300,7 +300,7 @@ excel_write_string (BiffPut *bp, WriteStringFlags flags,
                    guint8 const *txt)
 {
        size_t byte_len, out_bytes, offset = 0;
-       unsigned int char_len, output_len;
+       unsigned int char_len, output_len, avail;
        char *in_bytes = (char *)txt; /* bloody strict-aliasing is broken */
 
        g_return_val_if_fail (txt != NULL, 0);
@@ -335,7 +335,6 @@ excel_write_string (BiffPut *bp, WriteStringFlags flags,
                out_bytes = bp->buf_len - 3;
 
                tmp = (char *)(bp->buf + offset);
-
                g_iconv (bp->convert, &in_bytes, &byte_len, &tmp, &out_bytes);
                out_bytes = (guint8 *)tmp - bp->buf;
 
@@ -364,7 +363,26 @@ excel_write_string (BiffPut *bp, WriteStringFlags flags,
                case STR_FOUR_BYTE_LENGTH: GSF_LE_SET_GUINT32 (bp->buf, output_len); break;
                }
 
-               ms_biff_put_var_write (bp, bp->buf, out_bytes);
+               output_len = out_bytes;
+               tmp = bp->buf;
+               do {
+                       avail = ms_biff_max_record_len (bp);
+                       if (offset == 0 && bp->version >= MS_BIFF_V8 && !(flags & STR_SUPPRESS_HEADER)) {
+                               ms_biff_put_var_write (bp, "\1", 1);
+                               avail -= 2;
+                               out_bytes++;
+                       }
+                       avail = MIN (avail, output_len);
+                       avail = (avail - offset) / 2 * 2 + offset; /* we need to export an even byte number */
+                       ms_biff_put_var_write (bp, tmp, avail);
+                       output_len -= avail;
+                       tmp += avail;
+                       offset = 0;
+                       if (output_len > 0) {
+                               ms_biff_put_commit (bp);
+                               ms_biff_put_var_next (bp, BIFF_CONTINUE);
+                       }
+               } while (output_len > 0);
        } else {
                guint8 *tmp;
                /* char_len == byte_len here, so just use char_len */
@@ -384,11 +402,23 @@ excel_write_string (BiffPut *bp, WriteStringFlags flags,
                        tmp += 4;
                        break;
                }
-               if (bp->version >= MS_BIFF_V8 && !(flags & STR_SUPPRESS_HEADER))
-                       *tmp++ = 0;     /* flag as not unicode */
-               ms_biff_put_var_write (bp, bp->buf, tmp - bp->buf);
-               ms_biff_put_var_write (bp, txt, char_len);
-               out_bytes = char_len + tmp - bp->buf;
+               out_bytes =  tmp - bp->buf;
+               ms_biff_put_var_write (bp, bp->buf, out_bytes);
+               avail = ms_biff_max_record_len (bp) - out_bytes;
+               do {
+                       if (bp->version >= MS_BIFF_V8 && !(flags & STR_SUPPRESS_HEADER)) {
+                               *tmp++ = 0;     /* flag as not unicode */ /* Jean: MS docs say uncompressed */
+                               avail--;
+                               out_bytes++;
+                               ms_biff_put_var_write (bp, "\0", 1);
+                       }
+                       avail = MIN (avail, char_len);
+                       ms_biff_put_var_write (bp, txt, avail);
+                       out_bytes += avail;
+                       char_len -= avail;
+                       txt += avail;
+                       avail = ms_biff_max_record_len (bp);
+               } while (char_len > 0);
        }
 
        return out_bytes;
@@ -4252,7 +4282,7 @@ excel_write_ClientTextbox (ExcelWriteState *ewb, SheetObject *so,
 
        ms_biff_put_var_next (bp, BIFF_CONTINUE);
        memset (buf, 0, 8);
-       if (markup ) {
+       if (markup && markup->len > 0) {
                int n = markup->len / 2;
                int i;