From fa080de7afc95aa1c19a6e6fc0e0708ced2eadc4 Mon Sep 17 00:00:00 2001 From: Joseph Hunkeler Date: Wed, 8 Jul 2015 20:46:52 -0400 Subject: Initial commit --- pkg/tbtables/tbxsiz.x | 87 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 pkg/tbtables/tbxsiz.x (limited to 'pkg/tbtables/tbxsiz.x') diff --git a/pkg/tbtables/tbxsiz.x b/pkg/tbtables/tbxsiz.x new file mode 100644 index 00000000..bf74d467 --- /dev/null +++ b/pkg/tbtables/tbxsiz.x @@ -0,0 +1,87 @@ +include +include "tbtables.h" + +# tbxsiz -- X increase size +# Increase either the record size or the space for column descriptors +# for a table. If only the record size needs to be increased and no +# rows have yet been written to the table, this routine does nothing. +# Increasing the record size and/or space is done by copying the table +# data file to a temporary file, deleting the original table, and +# then renaming the temporary file to the name of the original table. +# The INDEF record buffer is copied to a local scratch buffer and then +# used for the I/O, so when this procedure returns, all existing rows should +# have the correct INDEF values set for the new columns. +# If the new row length is not the same as the previous value, the INDEF +# record buffer will be reallocated. +# The table must be open when this procedure is called. +# +# NOTE that the file channel number TB_FILE(tp) may be changed by this +# procedure. The values of TB_ROWLEN, TB_MAXPAR, TB_MAXCOLS and TB_BOD +# are assumed to have been updated by a calling routine (e.g. tbcdef). +# +# Phil Hodge, 28-Aug-1987 Flush file buffer after calling tbtwsi. +# Phil Hodge, 6-Nov-1987 Put temporary file in tmp. +# Phil Hodge, 24-Mar-1988 Save and restore FIO buffer size. +# Phil Hodge, 7-Mar-1989 Eliminate TB_CURROW. +# Phil Hodge, 1-May-1989 Realloc the INDEF record buffer. +# Phil Hodge, 30-Mar-1993 TB_INDEF is now TY_CHAR rather than TY_REAL. + +procedure tbxsiz (tp, old_maxpar, old_maxcols, + old_ncols, old_rowlen, old_colused) + +pointer tp # i: pointer to table descriptor +int old_maxpar # i: previous max number of user parameters +int old_maxcols # i: previous value for max number of columns +int old_ncols # i: previous number of columns +int old_rowlen # i: row length (=record len) in original table +int old_colused # i: previous number of char used in row +#-- +int iomode # I/O mode for reopening the table +int oldfd, newfd # channel numbers for old & new table files +int bufsize # save and restore FIO buffer size +char temp_file[SZ_FNAME] # name of temporary file for table data +int open(), fstati() +errchk realloc, tbtwsi, tbxscp, mktemp, open, close, delete, rename, flush + +begin + # Reallocate indef record if necessary. + if (TB_ROWLEN(tp) > old_rowlen) + call realloc (TB_INDEF(tp), TB_ROWLEN(tp), TY_CHAR) + + # First check whether we really have to do anything. + if ( (TB_NROWS(tp) <= 0) && (TB_MAXPAR(tp) == old_maxpar) && + (TB_MAXCOLS(tp) == old_maxcols) ) + return + + oldfd = TB_FILE(tp) + bufsize = fstati (oldfd, F_BUFSIZE) + + call mktemp ("tmp$tbl", temp_file, SZ_FNAME) + newfd = open (temp_file, NEW_FILE, BINARY_FILE) + + # Copy the contents of the table to the temporary file. + call tbxscp (tp, oldfd, newfd, old_maxpar, + old_maxcols, old_ncols, old_rowlen, old_colused) + + call close (oldfd) + call close (newfd) + + # Delete the original table that was too small, and rename the + # temporary table to the same name as the original. + call delete (TB_NAME(tp)) + call rename (temp_file, TB_NAME(tp)) + + # Reopen the new table. + if (TB_IOMODE(tp) == NEW_FILE) + iomode = READ_WRITE + else + iomode = TB_IOMODE(tp) + TB_FILE(tp) = open (TB_NAME(tp), iomode, BINARY_FILE) + + # Restore whatever buffer size the old table had. + call fseti (TB_FILE(tp), F_BUFSIZE, bufsize) + + # Update the size information record in the new table. + call tbtwsi (tp) # write size information + call flush (TB_FILE(tp)) +end -- cgit