printstat and awkprintf are very clear: print statement errors
are fatal.
In Jan 2020 [1], to prevent fatal print errors from masquerading
as fclose warnings, every WARNING in closefile and closeall became
FATAL. This broke awk's close and getline functions.
close no longer returns if there's an error, unless the stream
doesn't exist.
getline read errors still return -1, but they are no longer
ignorable. Eventually, one of the closing functions will inspect the
stream with ferror and call FATAL.
In Jul 2020 [2], fatal stdout write errors which had been detectable by
closefile for a few months became invisible, a consequence of switching
standard streams from fclose (which reports flush errors) to freopen
(which ignores them). The Jan 2020 changes which broke getline and
close were themselves partially broken.
The solution is to finish printing before closing. That is to flush
and ferror every stream opened for writing before calling fclose,
pclose, or freopen. A failure to write print statement data is
fatal. A failure to close a flushed stream is a warning. They must
be handled separately.
Every redirected print statement is finished in printstat or awkprintf.
The same is not true of unredirected print statements. To finish
these, stdout must be flushed at some point after the final such
statement. Any problem with that flush is fatal.
Though only stdout needs it, let's defensively finish every stream
opened for writing, so this bug won't recur if someone changes how
redirected streams are flushed.
Write errors on stderr by the implementation are never fatal. When
closing, we only warn of them. Write errors from an application
attempting a redirected print to /dev/stderr are as immediately fatal
as every other redirected print statement.
[1] fed1a562c3
[2] b82b649aa6
IEEE Std 1003.1-2008 mandates that -F str be treated the same as -v
FS=str. For a null string, this was not the case. Since awk(1) documents
that a null string for FS has a specific behavior, make -F '' behave
consistently with -v FS="".
PR:
upstream issue: https://github.com/onetrueawk/awk/issues/127
Sponsored by: Netflix
When awk reaches EOF parsing the program file, curpfile is incremented.
However, cursource() uses curpfile without checking it against npfile
which can cause an out of bounds access of pfile[] if there is a syntax
error at the end of the program file.
POSIX specifies a dprintf function that operates on an fd instead of
a stdio stream. Using upper case for macros is more idiomatic too.
We no longer need to use an extra set of parentheses for debugging
printf statements.
* LC_NUMERIC radix issue.
According to https://pubs.opengroup.org/onlinepubs/7990989775/xcu/awk.html
The period character is the character recognized in processing awk
programs. Make it so that during output we also print the period
character, since this is what other awk implementations do, and it
makes sense from an interoperability point of view.
* print "T.builtin" in the error message
* Fix backslash continuation line handling.
* Keep track of RS processing so we apply the regex properly only once
per record.
* - enhance fpe handler to print the error type
- cleanup argument parsing
- dynamically allocate program filename array
* bison uses enums now, not #define's, make it work with that.
* We need to use either the enums or the defines but not both. This
is because bison -y will create both enums and #defines, while bison
without -y produces only the enums, and byacc produces just #defines.
* fix indentation
* Set the tokentype when we have a match in the scan, and reset it later
when we decide that the match was bad. Fixes nbyacc.
* - don't use pattern rules for portability
- try to move both flavors of generated names for portability
* Amend tests for the new error messages
