On 25 June 2014 19:24, Stefan Fuhrmann <stefan.fuhrm...@wandisco.com> wrote: > On Wed, Jun 25, 2014 at 4:57 PM, Ivan Zhakov <i...@visualsvn.com> wrote: >> >> On 21 June 2014 17:15, <stef...@apache.org> wrote: >> > Author: stefan2 >> > Date: Sat Jun 21 15:15:30 2014 >> > New Revision: 1604421 >> > >> > URL: http://svn.apache.org/r1604421 >> > Log: >> > Append index data to the rev data file instead of using separate files. >> > >> > This gives unpacked FSFS format 7 similar I/O characteristics and disk >> > space usage as earlier formats. It also eliminates the need for retries >> > after a potential background pack run because each file is now always >> > consistent with itself (earlier, data or index files might already have >> > been deleted while the respective other was still valid). Overall, >> > most of this patch is removing code necessary to handle separate files. >> > >> > The new file format is simple: >> > >> > <rep data><l2p index><p2l index><footer><footer length> >> > >> > with the first three being identical what we had before. <footer length> >> > is a single byte giving the length of the preceding footer, so it's >> > easier to extract than the pre-f7 rev trailer and there is only one >> > per pack / rev file. >> > >> [..] >> >> >> >Modified: subversion/trunk/subversion/libsvn_fs_fs/fs_fs.c >> >URL: >> > http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_fs_fs/fs_fs.c?rev=1604421&r1=1604420&r2=1604421&view=diff >> >> > >============================================================================== >> >--- subversion/trunk/subversion/libsvn_fs_fs/fs_fs.c (original) >> >+++ subversion/trunk/subversion/libsvn_fs_fs/fs_fs.c Sat Jun 21 15:15:30 >> > 2014 >> >@@ -1449,15 +1449,35 @@ write_revision_zero(svn_fs_t *fs) >> >+ SVN_ERR(svn_io_file_create_binary(path_revision_zero, >> >+ "PLAIN\nEND\nENDREP\n" >> >+ "id: 0.0.r0/2\n" >> >+ "type: dir\n" >> >+ "count: 0\n" >> >+ "text: 0 3 4 4 " >> >+ "2d2977d1c96f487abe4a1e202dd03b4e\n" >> >+ "cpath: /\n" >> >+ "\n\n" >> >+ >> >+ /* L2P index */ >> >+ "\0\x80\x40" /* rev 0, 8k entries per page */ >> >+ "\1\1\1" /* 1 rev, 1 page, 1 page in 1st >> > rev */ >> >+ "\6\4" /* page size: bytes, count */ >> >+ "\0\xd6\1\xb1\1\x21" /* phys offsets + 1 */ >> >+ >> >+ /* P2L index */ >> >+ "\0\x6b" /* start rev, rev file size */ >> >+ "\x80\x80\4\1\x1D" /* 64k pages, 1 page using 29 >> > bytes */ >> >+ "\0" /* offset entry 0 page 1 */ >> >+ /* len, item & type, rev, >> > checksum */ >> >+ "\x11\x34\0\xf5\xd6\x8c\x81\x06" >> >+ "\x59\x09\0\xc8\xfc\xf6\x81\x04" >> >+ "\1\x0d\0\x9d\x9e\xa9\x94\x0f" >> >+ "\x95\xff\3\x1b\0\0" /* last entry fills up 64k page >> > */ >> >+ >> >+ /* Footer */ >> >+ "107 121\7", >> >+ 107 + 14 + 38 + 7 + 1, fs->pool)); >> This constant makes code unreadable, unmaintainable and very error prone. > > > How? > > To make it more obvious that I intend to follow > the svn_io_file_create_binary interface, I added > some commentary explaining where the numbers > come from. But even just placing the sum (without > its elements) in there would be fine already. > > Changing the rev 0 template has never been a fun > activity and wont become one in the foreseeable > future. > I believe that the committer should be responsible forcommitting readable and easy to maintain code, not the reviewer. So please fix or revert.
>> >> >> > Modified: subversion/trunk/subversion/libsvn_fs_fs/rev_file.c >> > URL: >> > http://svn.apache.org/viewvc/subversion/trunk/subversion/libsvn_fs_fs/rev_file.c?rev=1604421&r1=1604420&r2=1604421&view=diff >> > >> > ============================================================================== >> > --- subversion/trunk/subversion/libsvn_fs_fs/rev_file.c (original) >> > +++ subversion/trunk/subversion/libsvn_fs_fs/rev_file.c Sat Jun 21 >> > 15:15:30 2014 >> > @@ -23,6 +23,7 @@ >> > #include "rev_file.h" >> > #include "fs_fs.h" >> > #include "index.h" >> > +#include "low_level.h" >> > #include "util.h" >> > >> > #include "../libsvn_fs/fs-loader.h" >> > @@ -46,6 +47,10 @@ init_revision_file(svn_fs_fs__revision_f >> > file->stream = NULL; >> > file->p2l_stream = NULL; >> > file->l2p_stream = NULL; >> > + file->block_size = ffd->block_size; >> > + file->l2p_offset = -1; >> > + file->p2l_offset = -1; >> > + file->footer_offset = -1; >> > file->pool = pool; >> > } >> > >> > @@ -127,14 +132,40 @@ svn_fs_fs__open_pack_or_rev_file(svn_fs_ >> > } >> > >> > svn_error_t * >> > -svn_fs_fs__reopen_revision_file(svn_fs_fs__revision_file_t *file, >> > - svn_fs_t *fs, >> > - svn_revnum_t rev) >> > +svn_fs_fs__auto_read_footer(svn_fs_fs__revision_file_t *file) >> > { >> > - if (file->file) >> > - svn_fs_fs__close_revision_file(file); >> > + if (file->l2p_offset == -1) >> > + { >> > + apr_off_t filesize = 0; >> > + unsigned char footer_length; >> > + svn_stringbuf_t *footer; >> > + >> > + /* Determine file size. */ >> > + SVN_ERR(svn_io_file_seek(file->file, APR_END, &filesize, >> > file->pool)); >> > + >> > + /* Read last byte (containing the length of the footer). */ >> > + SVN_ERR(svn_io_file_aligned_seek(file->file, file->block_size, >> > NULL, >> > + filesize - 1, file->pool)); >> > + SVN_ERR(svn_io_file_read_full2(file->file, &footer_length, >> > + sizeof(footer_length), NULL, NULL, >> > + file->pool)); >> > + >> > + /* Read footer. */ >> > + footer = svn_stringbuf_create_ensure(footer_length, file->pool); >> > + SVN_ERR(svn_io_file_aligned_seek(file->file, file->block_size, >> > NULL, >> > + filesize - 1 - footer_length, >> > + file->pool)); >> > + SVN_ERR(svn_io_file_read_full2(file->file, footer->data, >> > footer_length, >> > + &footer->len, NULL, file->pool)); >> You're passing pointer to possible 32-bit value to function accepting >> pointer to 64-bit value. This will lead unpredictable results. > > > I assume you are referring to the &footer->len? > In that case, I think I'm passing an apr_size_t* > to an interface expecting an apr_size_t*. > What am I missing? > You're right. I confused svn_io_file_read_full2() with svn_io_file_seek(). The code above doesn't have problem I mentioned. -- Ivan Zhakov CTO | VisualSVN | http://www.visualsvn.com
