* geesh/shell.scm (ignore-errexit?): New parameter.
(without-errexit): New function.
(errexit): New function.
(sh:exec-let, sh:set-redirects, sh:with-redirects, sh:subshell,
sh:substitute-command, sh:pipeline, sh:and, sh:or, sh:not, sh:while,
sh:cond): Use it to exit on nonzero status.
Instead of passing around references to the environment, just treat it
as a global. The old way was just the remains of an idea to make the
environment immutable and keep the interpreter from manipulating any
global state. By making everything global and mutable, we will have
less impedance mismatch with POSIX going forward.
The following changelog is only a sketch, since nearly every function
has changed.
* geesh/environment.scm: Replace this module with one that treats the
environment as a global resource.
* tests/environment.scm: Delete file.
* Makefile.am: Remove it from the list of tests.
* geesh/shell.scm, geesh/eval.scm, geesh/repl.scm, geesh/word.scm,
geesh/built-ins/break.scm, geesh/built-ins/continue.scm,
geesh/built-ins/echo.scm, geesh/built-ins/export.scm,
geesh/built-ins/false.scm, geesh/built-ins/read.scm,
geesh/built-ins/readonly.scm, geesh/built-ins/set.scm,
geesh/built-ins/true.scm, geesh/built-ins/unset.scm: Remove 'env'
parameters and use the new environment module.
* .dir-locals.el: Update indentation of functions that no longer take
an 'env' parameter and add with-arguments, with-environ, and
with-variables from the new environment module.
* tests/shell.scm, tests/word.scm: Update environment creation and
manipulation in tests.
* geesh/shell.scm (sh:set-redirects): New public function.
* geesh/eval.scm (eval-sh): Use it to handle 'exec' specially when
called with redirects but no arguments.
This was simply a mistake.
* geesh/shell.scm (sh:substitute-command): Leave 'current-input-port'
and 'current-error-port' alone.
* tests/shell.scm: Remove tests that check that input and error gets
ignored during substitutions.
Instead of saving and restoring redirects manually, if we let them all
be parameters (like 'current-input-port'), we can use 'parameterize'
and make Guile take of this for us. As a side-effect of this change,
redirect errors get handled.
* geesh/shell.scm (save-and-set-redirect): Rename this...
(redir->parameter+port): ...to this and change the return value to be
a pair consisting of a parameter and a port.
(restore-saved-port): Remove function.
(sh:with-redirects): Use 'parameterize' to effect redirects rather
than updating them and restoring them manually.
There are two issues that arise due to output port buffers and
forking. If we run Scheme code in a child process, we need to avoid
copying buffered output into the child process. Otherwise, the
buffered output could be written twice. If we run non-Scheme
code (i.e., exec), we need to flush the ports to ensure proper
sequencing of writes since the non-Scheme code will not know about the
buffered output and will write its output before the buffer gets
flushed.
* geesh/shell.scm (exec-utility): Flush all ports before forking.
(%subshell): Ditto.
Instead of using an environment variable named '?', we will use a
special environment field called 'status'. This lets us get rid of a
lot of number-string conversions (since an environment variable has to
have a string value).
* geesh/environment.scm (<environment>): Add a 'status' field.
(make-environment): Set it to 0 by default.
* geesh/repl.scm (run-repl): Use new field in place of '?' variable.
* geesh/shell.scm (exec-utility, sh:and, sh:exec-let, sh:for, sh:not,
sh:or, sh:pipeline, sh:subshell, sh:substitute-command): Ditto.
* geesh/word.scm (parameter-ref): New function that handles both
special parameters (e.g., '?') and variables.
(parameter-ref*): Like 'var-ref*', but for 'parameter-ref'.
(word->qword): Replace 'var-ref' and 'var-ref*' with 'parameter-ref'
and 'parameter-ref*' respectively.
* geesh/shell.scm (swap-and-shift-pairs): New function.
(make-pipes): New function.
(plumb): New function.
(sh:pipeline): New public function.
* tests/shell.scm: Test it.
Before, we were using raw file descriptors. This worked okay, but
there was interference caused by port buffering. Doing everything at
the port level avoids this problem, and has the added benefit of
allowing one to use the 'current-*-port' parameters with the shell
module (in a limited way, but there is room for improvement).
* geesh/shell.scm (*fd-count*): New variable.
(fd->current-port): New function.
(install-current-ports!): New function.
(exec-utility): Use it to set up file descriptors.
(save-and-install-redirect!): Rename this...
(save-and-set-redirect): ...to this and modify the current port
parameters instead of raw file descriptors.
(restore-saved-fdes!): Rename this...
(restore-saved-port): ...to this.
(sh:with-redirects): Adjust to use the renamed functions.
(sh:substitute-command): Parameterize the current ports directly
instead of using redirects.
* tests/shell.scm: Add tests to check if port buffers cause problems.
* geesh/shell.scm (%subshell): New function factored out from 'subshell'.
(subshell): Use it.
(substitute-command): New public function.
* tests/shell.scm: Test it.
* .dir-locals.el: Indent it nicely.
* geesh/shell.scm (save-and-install-redirect!): New function.
(restore-saved-fdes!): New function.
(with-redirects): New public function.
* tests/shell.scm: Test it.
* .dir-locals.el: Indent it nicely.
* geesh/built-ins/echo.scm: New file.
* geesh/built-ins.scm: New file.
* Makefile.scm: Add them.
* geesh/shell.scm (exec-let): Include built-ins in command search.
* tests/shell.scm: Add a test for this.
* geesh/shell.scm (slashless?) New function.
(split-search-path): New function.
(find-utility): New function.
(exec-let): Use them to search PATH for a utility when appropriate.
(exec): Update doc string.
* tests/shell.scm: Test it.
Timothy Sample