diff options
Diffstat (limited to 'mysql/mysys/my_file.c')
| -rw-r--r-- | mysql/mysys/my_file.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/mysql/mysys/my_file.c b/mysql/mysys/my_file.c new file mode 100644 index 0000000..b2faed0 --- /dev/null +++ b/mysql/mysys/my_file.c @@ -0,0 +1,144 @@ +/* Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ + +#include "mysys_priv.h" +#include "my_static.h" +#include <m_string.h> +#ifdef HAVE_SYS_RESOURCE_H +#include <sys/resource.h> /* RLIMIT_NOFILE */ +#endif + +/* + set how many open files we want to be able to handle + + SYNOPSIS + set_maximum_open_files() + max_file_limit Files to open + + NOTES + The request may not fulfilled becasue of system limitations + + RETURN + Files available to open. + May be more or less than max_file_limit! +*/ + +#if defined(HAVE_GETRLIMIT) + +/* + This value is certainly wrong on all 64bit platforms, + and also wrong on many 32bit platforms. + It is better to get a compile error, than to use a wrong value. +#ifndef RLIM_INFINITY +#define RLIM_INFINITY ((uint) 0xffffffff) +#endif +*/ + +static uint set_max_open_files(uint max_file_limit) +{ + struct rlimit rlimit; + uint old_cur; + DBUG_ENTER("set_max_open_files"); + DBUG_PRINT("enter",("files: %u", max_file_limit)); + + if (!getrlimit(RLIMIT_NOFILE,&rlimit)) + { + old_cur= (uint) rlimit.rlim_cur; + DBUG_PRINT("info", ("rlim_cur: %u rlim_max: %u", + (uint) rlimit.rlim_cur, + (uint) rlimit.rlim_max)); + if (rlimit.rlim_cur == (rlim_t) RLIM_INFINITY) + rlimit.rlim_cur = max_file_limit; + if (rlimit.rlim_cur >= max_file_limit) + DBUG_RETURN(rlimit.rlim_cur); /* purecov: inspected */ + rlimit.rlim_cur= rlimit.rlim_max= max_file_limit; + if (setrlimit(RLIMIT_NOFILE, &rlimit)) + max_file_limit= old_cur; /* Use original value */ + else + { + rlimit.rlim_cur= 0; /* Safety if next call fails */ + (void) getrlimit(RLIMIT_NOFILE,&rlimit); + DBUG_PRINT("info", ("rlim_cur: %u", (uint) rlimit.rlim_cur)); + if (rlimit.rlim_cur) /* If call didn't fail */ + max_file_limit= (uint) rlimit.rlim_cur; + } + } + DBUG_PRINT("exit",("max_file_limit: %u", max_file_limit)); + DBUG_RETURN(max_file_limit); +} + +#else +static uint set_max_open_files(uint max_file_limit) +{ + /* We don't know the limit. Return best guess */ + return MY_MIN(max_file_limit, OS_FILE_LIMIT); +} +#endif + + +/* + Change number of open files + + SYNOPSIS: + my_set_max_open_files() + files Number of requested files + + RETURN + number of files available for open +*/ + +uint my_set_max_open_files(uint files) +{ + struct st_my_file_info *tmp; + DBUG_ENTER("my_set_max_open_files"); + DBUG_PRINT("enter",("files: %u my_file_limit: %u", files, my_file_limit)); + + files+= MY_FILE_MIN; + files= set_max_open_files(MY_MIN(files, OS_FILE_LIMIT)); + if (files <= MY_NFILE) + DBUG_RETURN(files); + + if (!(tmp= (struct st_my_file_info*) my_malloc(key_memory_my_file_info, + sizeof(*tmp) * files, + MYF(MY_WME)))) + DBUG_RETURN(MY_NFILE); + + /* Copy any initialized files */ + memcpy((char*) tmp, (char*) my_file_info, + sizeof(*tmp) * MY_MIN(my_file_limit, files)); + memset((tmp + my_file_limit), 0, + MY_MAX((int) (files - my_file_limit), 0) * sizeof(*tmp)); + my_free_open_file_info(); /* Free if already allocated */ + my_file_info= tmp; + my_file_limit= files; + DBUG_PRINT("exit",("files: %u", files)); + DBUG_RETURN(files); +} + + +void my_free_open_file_info() +{ + DBUG_ENTER("my_free_file_info"); + if (my_file_info != my_file_info_default) + { + /* Copy data back for my_print_open_files */ + memcpy((char*) my_file_info_default, my_file_info, + sizeof(*my_file_info_default)* MY_NFILE); + my_free(my_file_info); + my_file_info= my_file_info_default; + my_file_limit= MY_NFILE; + } + DBUG_VOID_RETURN; +} |