/* Copyright (C) 2000 MySQL AB
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; either version 2 of the License, or
(at your option) any later version.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
More functions to be used with IO_CACHE files
*/
#define MAP_TO_USE_RAID
#include "mysys_priv.h"
#include <m_string.h>
#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.
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 occured
*/
int
my_b_copy_to_file(IO_CACHE *cache, FILE *file)
{
byte buf[IO_SIZE];
uint 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);
while (bytes_in_cache > 0) {
uint const read_bytes= min(bytes_in_cache, sizeof(buf));
DBUG_PRINT("debug", ("Remaining %u bytes - Reading %u bytes",
bytes_in_cache, read_bytes));
if (my_b_read(cache, buf, read_bytes))
DBUG_RETURN(1);
if (my_fwrite(file, buf, read_bytes, MYF(MY_WME | MY_NABP)) == (uint) -1)
DBUG_RETURN(1);
bytes_in_cache -= read_bytes;
}
DBUG_RETURN(0);
}
my_off_t my_b_append_tell(IO_CACHE* info)
{
/*
Prevent optimizer from putting res in a register when debugging
we need this to be able to see the value of res when the assert fails
*/
dbug_volatile my_off_t res;
/*
We need to lock the append buffer mutex to keep flush_io_cache()
from messing with the variables that we need in order to provide the
answer to the question.
*/
#ifdef THREAD
pthread_mutex_lock(&info->append_buffer_lock);
#endif
#ifndef DBUG_OFF
/*
Make sure EOF is where we think it is. Note that we cannot just use
my_tell() because we have a reader thread that could have left the
file offset in a non-EOF location
*/
{
volatile my_off_t save_pos;
save_pos = my_tell(info->file,MYF(0));
my_seek(info->file,(my_off_t)0,MY_SEEK_END,MYF(0));
/*
Save the value of my_tell in res so we can see it when studying coredump
*/
DBUG_ASSERT(info->end_of_file - (info->append_read_pos-info->write_buffer)
== (res=my_tell(info->file,MYF(0))));
my_seek(info->file,save_pos,MY_SEEK_SET,MYF(0));
}
#endif
res = info->end_of_file + (info->write_pos-info->append_read_pos);
#ifdef THREAD
pthread_mutex_unlock(&info->append_buffer_lock);
#endif
return res;
}
my_off_t my_b_safe_tell(IO_CACHE *info)
{
if (unlikely(info->type == SEQ_READ_APPEND))
return my_b_append_tell(info);
return my_b_tell(info);
}
/*
Make next read happen at the given position
For write cache, make next write happen at the given position
*/
void my_b_seek(IO_CACHE *info,my_off_t pos)
{
my_off_t offset;
DBUG_ENTER("my_b_seek");
DBUG_PRINT("enter",("pos: %lu", (ulong) pos));
/*
TODO:
Verify that it is OK to do seek in the non-append
area in SEQ_READ_APPEND cache
a) see if this always works
b) see if there is a better way to make it work
*/
if (info->type == SEQ_READ_APPEND)
VOID(flush_io_cache(info));
offset=(pos - info->pos_in_file);
if (info->type == READ_CACHE || info->type == SEQ_READ_APPEND)
{
/* TODO: explain why this works if pos < info->pos_in_file */
if ((ulonglong) offset < (ulonglong) (info->read_end - info->buffer))
{
/* The read is in the current buffer; Reuse it */
info->read_pos = info->buffer + offset;
DBUG_VOID_RETURN;
}
else
{
/* Force a new read on next my_b_read */
info->read_pos=info->read_end=info->buffer;
}
}
else if (info->type == WRITE_CACHE)
{
/* If write is in current buffer, reuse it */
if ((ulonglong) offset <
(ulonglong) (info->write_end - info->write_buffer))
{
info->write_pos = info->write_buffer + offset;
DBUG_VOID_RETURN;
}
VOID(flush_io_cache(info));
/* Correct buffer end so that we write in increments of IO_SIZE */
info->write_end=(info->write_buffer+info->buffer_length-
(pos & (IO_SIZE-1)));
}
info->pos_in_file=pos;
info->seek_not_done=1;
DBUG_VOID_RETURN;
}
/*
Fill buffer. Note that this assumes that you have already used
all characters in the CACHE, independent of the read_pos value!
return: 0 on error or EOF (info->error = -1 on error)
number of characters
*/
uint my_b_fill(IO_CACHE *info)
{
my_off_t pos_in_file=(info->pos_in_file+
(uint) (info->read_end - info->buffer));
my_off_t max_length;
uint diff_length,length;
if (info->seek_not_done)
{ /* File touched, do seek */
if (my_seek(info->file,pos_in_file,MY_SEEK_SET,MYF(0)) ==
MY_FILEPOS_ERROR)
{
info->error= 0;
return 0;
}
info->seek_not_done=0;
}
diff_length=(uint) (pos_in_file & (IO_SIZE-1));
max_length= (my_off_t) (info->end_of_file - pos_in_file);
if (max_length > (my_off_t) (info->read_length-diff_length))
max_length=(my_off_t) (info->read_length-diff_length);
if (!max_length)
{
info->error= 0;
return 0; /* EOF */
}
else if ((length=my_read(info->file,info->buffer,(uint) max_length,
info->myflags)) == (uint) -1)
{
info->error= -1;
return 0;
}
info->read_pos=info->buffer;
info->read_end=info->buffer+length;
info->pos_in_file=pos_in_file;
return length;
}
/*
Read a string ended by '\n' into a buffer of 'max_length' size.
Returns number of characters read, 0 on error.
last byte is set to '\0'
If buffer is full then to[max_length-1] will be set to \0.
*/
uint my_b_gets(IO_CACHE *info, char *to, uint max_length)
{
char *start = to;
uint length;
max_length--; /* Save place for end \0 */
/* Calculate number of characters in buffer */
if (!(length= my_b_bytes_in_cache(info)) &&
!(length= my_b_fill(info)))
return 0;
for (;;)
{
char *pos,*end;
if (length > max_length)
length=max_length;
for (pos=info->read_pos,end=pos+length ; pos < end ;)
{
if ((*to++ = *pos++) == '\n')
{
info->read_pos=pos;
*to='\0';
return (uint) (to-start);
}
}
if (!(max_length-=length))
{
/* Found enough charcters; Return found string */
info->read_pos=pos;
*to='\0';
return (uint) (to-start);
}
if (!(length=my_b_fill(info)))
return 0;
}
}
my_off_t my_b_filelength(IO_CACHE *info)
{
if (info->type == WRITE_CACHE)
{
return my_b_tell(info);
}
else
{
info->seek_not_done=1;
return my_seek(info->file,0L,MY_SEEK_END,MYF(0));
}
}
/*
Simple printf version. Supports '%s', '%d', '%u', "%ld" and "%lu"
Used for logging in MySQL
returns number of written character, or (uint) -1 on error
*/
uint my_b_printf(IO_CACHE *info, const char* fmt, ...)
{
int result;
va_list args;
va_start(args,fmt);
result=my_b_vprintf(info, fmt, args);
va_end(args);
return result;
}
uint my_b_vprintf(IO_CACHE *info, const char* fmt, va_list args)
{
uint out_length=0;
uint minimum_width; /* as yet unimplemented */
uint minimum_width_sign;
uint precision; /* as yet unimplemented for anything but %b */
/*
Store the location of the beginning of a format directive, for the
case where we learn we shouldn't have been parsing a format string
at all, and we don't want to lose the flag/precision/width/size
information.
*/
const char* backtrack;
for (; *fmt != '\0'; fmt++)
{
/* Copy everything until '%' or end of string */
const char *start=fmt;
uint length;
for (; (*fmt != '\0') && (*fmt != '%'); fmt++) ;
length= (uint) (fmt - start);
out_length+=length;
if (my_b_write(info, start, length))
goto err;
if (*fmt == '\0') /* End of format */
{
return out_length;
}
/*
By this point, *fmt must be a percent; Keep track of this location and
skip over the percent character.
*/
DBUG_ASSERT(*fmt == '%');
backtrack= fmt;
fmt++;
minimum_width= 0;
precision= 0;
minimum_width_sign= 1;
/* Skip if max size is used (to be compatible with printf) */
while (*fmt == '-') { fmt++; minimum_width_sign= -1; }
if (*fmt == '*') {
precision= (int) va_arg(args, int);
fmt++;
} else {
while (my_isdigit(&my_charset_latin1, *fmt)) {
minimum_width=(minimum_width * 10) + (*fmt - '0');
fmt++;
}
}
minimum_width*= minimum_width_sign;
if (*fmt == '.') {
fmt++;
if (*fmt == '*') {
precision= (int) va_arg(args, int);
fmt++;
} else {
while (my_isdigit(&my_charset_latin1, *fmt)) {
precision=(precision * 10) + (*fmt - '0');
fmt++;
}
}
}
if (*fmt == 's') /* String parameter */
{
reg2 char *par = va_arg(args, char *);
uint length = (uint) strlen(par);
/* TODO: implement minimum width and precision */
out_length+=length;
if (my_b_write(info, par, length))
goto err;
}
else if (*fmt == 'b') /* Sized buffer parameter, only precision makes sense */
{
char *par = va_arg(args, char *);
out_length+= precision;
if (my_b_write(info, par, precision))
goto err;
}
else if (*fmt == 'd' || *fmt == 'u') /* Integer parameter */
{
register int iarg;
uint length;
char buff[17];
iarg = va_arg(args, int);
if (*fmt == 'd')
length= (uint) (int10_to_str((long) iarg,buff, -10) - buff);
else
length= (uint) (int10_to_str((long) (uint) iarg,buff,10)- buff);
out_length+=length;
if (my_b_write(info, buff, length))
goto err;
}
else if ((*fmt == 'l' && fmt[1] == 'd') || fmt[1] == 'u')
/* long parameter */
{
register long iarg;
uint length;
char buff[17];
iarg = va_arg(args, long);
if (*++fmt == 'd')
length= (uint) (int10_to_str(iarg,buff, -10) - buff);
else
length= (uint) (int10_to_str(iarg,buff,10)- buff);
out_length+=length;
if (my_b_write(info, buff, length))
goto err;
}
else
{
/* %% or unknown code */
if (my_b_write(info, backtrack, fmt-backtrack))
goto err;
out_length+= fmt-backtrack;
}
}
return out_length;
err:
return (uint) -1;
}