b9396daf1c
The BMP index (font->bmp_idx) is designed as a reverse lookup table of char entries (font->char_index), in order to speed up lookups for BMP chars (i.e. code < 0x10000). The values in BMP index are the subscripts of the corresponding char entries, stored in grub_uint16_t, while 0xffff means not found. This patch fixes the problem of large subscript truncated to grub_uint16_t, leading BMP index to return wrong char entry or report false miss. The code now checks for bounds and uses BMP index as a hint, and fallbacks to binary-search if necessary. On the occasion add a comment about BMP index is initialized to 0xffff. Signed-off-by: Zhang Boyang <zhangboyang.id@gmail.com> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This is GRUB 2, the second version of the GRand Unified Bootloader. GRUB 2 is rewritten from scratch to make GNU GRUB cleaner, safer, more robust, more powerful, and more portable. See the file NEWS for a description of recent changes to GRUB 2. See the file INSTALL for instructions on how to build and install the GRUB 2 data and program files. See the file MAINTAINERS for information about the GRUB maintainers, etc. If you found a security vulnerability in the GRUB please check the SECURITY file to get more information how to properly report this kind of bugs to the maintainers. Please visit the official web page of GRUB 2, for more information. The URL is <http://www.gnu.org/software/grub/grub.html>. More extensive documentation is available in the Info manual, accessible using 'info grub' after building and installing GRUB 2. There are a number of important user-visible differences from the first version of GRUB, now known as GRUB Legacy. For a summary, please see: info grub Introduction 'Changes from GRUB Legacy'