From f88269794e8e6ab4433fc4b34aea12e5de2dd86c Mon Sep 17 00:00:00 2001 From: unknown Date: Wed, 2 Mar 2005 18:14:58 -0800 Subject: Avoid calls to my_seek() and my_tell() on log files so that non-seekable files like FIFOs can be used for logs other than the binlog. (Bug #8271) include/my_sys.h: Add APPEND_CACHE cache type mysys/mf_iocache.c: Handle APPEND_CACHE cache type to avoid calling my_seek() and my_tell() on logs opened O_APPEND that we never read from (so they can be a non-seekable file like a FIFO). sql/mysqld.cc: Use APPEND_CACHE for log files not set to SEQ_READ_APPEND. --- mysys/mf_iocache.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'mysys') diff --git a/mysys/mf_iocache.c b/mysys/mf_iocache.c index a7937da0cc2..e8cef2a2529 100644 --- a/mysys/mf_iocache.c +++ b/mysys/mf_iocache.c @@ -88,7 +88,7 @@ static void my_aiowait(my_aio_result *result); void setup_io_cache(IO_CACHE* info) { /* Ensure that my_b_tell() and my_b_bytes_in_cache works */ - if (info->type == WRITE_CACHE) + if (info->type == WRITE_CACHE || info->type == APPEND_CACHE) { info->current_pos= &info->write_pos; info->current_end= &info->write_end; @@ -223,7 +223,7 @@ int init_io_cache(IO_CACHE *info, File file, uint cachesize, #endif } - if (type == WRITE_CACHE) + if (type == WRITE_CACHE || type == APPEND_CACHE) info->write_end= info->buffer+info->buffer_length- (seek_offset & (IO_SIZE-1)); else @@ -293,6 +293,7 @@ my_bool reinit_io_cache(IO_CACHE *info, enum cache_type type, /* One can't do reinit with the following types */ DBUG_ASSERT(type != READ_NET && info->type != READ_NET && type != WRITE_NET && info->type != WRITE_NET && + type != APPEND_CACHE && info->type != APPEND_CACHE && type != SEQ_READ_APPEND && info->type != SEQ_READ_APPEND); /* If the whole file is in memory, avoid flushing to disk */ @@ -1098,7 +1099,8 @@ int my_b_flush_io_cache(IO_CACHE *info, int need_append_buffer_lock) my_off_t pos_in_file; DBUG_ENTER("my_b_flush_io_cache"); - if (!(append_cache = (info->type == SEQ_READ_APPEND))) + if (!(append_cache = (info->type == SEQ_READ_APPEND || + info->type == APPEND_CACHE))) need_append_buffer_lock=0; if (info->type == WRITE_CACHE || append_cache) @@ -1145,7 +1147,13 @@ int my_b_flush_io_cache(IO_CACHE *info, int need_append_buffer_lock) else { info->end_of_file+=(info->write_pos-info->append_read_pos); - DBUG_ASSERT(info->end_of_file == my_tell(info->file,MYF(0))); + /* + We only need to worry that info->end_of_file is really accurate + for SEQ_READ_APPEND. For APPEND_CACHE, it is possible that the + file is non-seekable, like a FIFO. + */ + DBUG_ASSERT(info->type != SEQ_READ_APPEND || + info->end_of_file == my_tell(info->file,MYF(0))); } info->append_read_pos=info->write_pos=info->write_buffer; -- cgit v1.2.1