diff options
Diffstat (limited to 'mysys')
| -rw-r--r-- | mysys/mf_iocache2.c | 61 |
1 files changed, 33 insertions, 28 deletions
diff --git a/mysys/mf_iocache2.c b/mysys/mf_iocache2.c index fa3b6e672d7..f3877331664 100644 --- a/mysys/mf_iocache2.c +++ b/mysys/mf_iocache2.c @@ -23,51 +23,56 @@ #include <stdarg.h> #include <m_ctype.h> -/* - Copy contents of an IO_CACHE to a file. - - SYNOPSIS - my_b_copy_to_file() - cache IO_CACHE to copy from - file File to copy to - - DESCRIPTION - Copy the contents of the cache to the file. The cache will be - re-inited to a read cache and will read from the beginning of the - cache. - - If a failure to write fully occurs, the cache is only copied - partially. +/** + Copy the cache to the file. Copying can be constrained to @c count + number of bytes when the parameter is less than SIZE_T_MAX. The + cache will be optionally re-inited to a read cache and will read + from the beginning of the cache. If a failure to write fully + occurs, the cache is only copied partially. TODO - Make this function solid by handling partial reads from the cache - in a correct manner: it should be atomic. - - RETURN VALUE - 0 All OK - 1 An error occurred + Make this function solid by handling partial reads from the cache + in a correct manner: it should be atomic. + + @param cache IO_CACHE to copy from + @param file File to copy to + @param count the copied size or the max of the type + when the whole cache is to be copied. + @return + 0 All OK + 1 An error occurred */ int -my_b_copy_to_file(IO_CACHE *cache, FILE *file) +my_b_copy_to_file(IO_CACHE *cache, FILE *file, + size_t count) { - size_t bytes_in_cache; + size_t curr_write, bytes_in_cache; DBUG_ENTER("my_b_copy_to_file"); - /* Reinit the cache to read from the beginning of the cache */ - if (reinit_io_cache(cache, READ_CACHE, 0L, FALSE, FALSE)) - DBUG_RETURN(1); bytes_in_cache= my_b_bytes_in_cache(cache); do { - if (my_fwrite(file, cache->read_pos, bytes_in_cache, + curr_write= MY_MIN(bytes_in_cache, count); + if (my_fwrite(file, cache->read_pos, curr_write, MYF(MY_WME | MY_NABP)) == (size_t) -1) DBUG_RETURN(1); - } while ((bytes_in_cache= my_b_fill(cache))); + + cache->read_pos += curr_write; + count -= curr_write; + } while (count && (bytes_in_cache= my_b_fill(cache))); if(cache->error == -1) DBUG_RETURN(1); DBUG_RETURN(0); } +int my_b_copy_all_to_file(IO_CACHE *cache, FILE *file) +{ + DBUG_ENTER("my_b_copy_all_to_file"); + /* Reinit the cache to read from the beginning of the cache */ + if (reinit_io_cache(cache, READ_CACHE, 0L, FALSE, FALSE)) + DBUG_RETURN(1); + DBUG_RETURN(my_b_copy_to_file(cache, file, SIZE_T_MAX)); +} my_off_t my_b_append_tell(IO_CACHE* info) { |