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. > > > 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? -- Stefan^2.
