dwarvish.git, branch signal a (mostly) posix compliant shell and tiny functional programming language Replace ctrlc with signal-hook 2024-02-25T04:24:19+00:00 Rory Dudley 2024-02-25T04:24:19+00:00 b6fc81066cfcc29d4519191eae5ba19581ad2774 Replaced the 'ctrlc' crate with 'signal-hook' for handling of SIGINT. The 'signal_hook::low_level::register' function is actually unsafe. However, according to https://docs.rs/signal-hook/latest/signal_hook/low_level/fn.register.html, it is only unsafe in the case of multithreaded applications. There are some race conditions as well. For instance, it appears that even when we fork to a child process, SIGINT is captured on both that process, as well as the shell. 
Replaced the 'ctrlc' crate with 'signal-hook' for handling of SIGINT.
The 'signal_hook::low_level::register' function is actually unsafe.
However, according to
https://docs.rs/signal-hook/latest/signal_hook/low_level/fn.register.html,
it is only unsafe in the case of multithreaded applications. There are
some race conditions as well. For instance, it appears that even when we
fork to a child process, SIGINT is captured on both that process, as
well as the shell.
Reorganization and comments 2024-02-23T06:12:24+00:00 Rory Dudley 2024-02-23T06:12:24+00:00 536e250653e5c140a6d9e60f1cd652b79135e7a6 Broke out the structs for a poem into their own file: src/recite.rs. Also put the 'prefresh' function into it's own file: src/recite/path.rs. Commented most of the parser code (including structs and helper methods related to parsing (i.e. Verse, Stanza, Meter, Poem)). Renamed any instance of the 'paths' variable to 'path'. 
Broke out the structs for a poem into their own file: src/recite.rs.
Also put the 'prefresh' function into it's own file: src/recite/path.rs.
Commented most of the parser code (including structs and helper methods
related to parsing (i.e. Verse, Stanza, Meter, Poem)). Renamed any
instance of the 'paths' variable to 'path'.
Add back the 'cd' command 2024-02-21T06:18:42+00:00 Rory Dudley 2024-02-21T06:18:42+00:00 a14fdf8faa85628baf06399961eb1f9ab4c5f3eb Add back change directory functionality into the new parser. 
Add back change directory functionality into the new parser.
Parsing improvements 2024-02-20T23:29:29+00:00 Rory Dudley 2024-02-20T23:29:29+00:00 309a101a0e09ffe2bcd4f0032744f8532a5988d1 Now the parser goes char by char, since special characters like '|' and '&' don't necessarily have to be whitespace seperated. Also added some VERY basic error detection for the parser (revolving around special chars). 
Now the parser goes char by char, since special characters like '|' and
'&' don't necessarily have to be whitespace seperated. Also added some
VERY basic error detection for the parser (revolving around special
chars).
Pipes, forks, and consecutive calls 2024-02-20T09:49:20+00:00 Rory Dudley 2024-02-20T09:49:20+00:00 5d7e3646b7a267bdcf068d5667201033b3aa9207 This adds some preliminary support for pipes (|), forks (&), and consecutive command calls (&&) to the shell. 
This adds some preliminary support for pipes (|), forks (&), and
consecutive command calls (&&) to the shell.
Only print command name in error messages 2024-02-20T00:45:14+00:00 Rory Dudley 2024-02-20T00:45:14+00:00 de2fe9dd7f2836f89490b822ae4464dab3bc769c Only print out the command name in error messages, rather than printing out the full path to the command. 
Only print out the command name in error messages, rather than printing
out the full path to the command.
Merge pull request #2 from pinecat/evryloop 2024-02-20T00:29:54+00:00 Rory D 2024-02-20T00:29:54+00:00 52422d40316f4d836a96a15709c2f4fad7c96d3b Path refresh 
Path refresh
 Path refresh refactor, comments, and error messages 2024-02-20T00:09:07+00:00 Rory Dudley 2024-02-20T00:09:07+00:00 d98ab111eebfcf5e6327daaec17b5de578d64a41 The 'eval' function was renamed to 'repl'. The code to refresh the $PATH was moved into it's own function: 'prefresh', and is now being called in three locations: - At the beginning of 'repl', before the main loop - Inside the main loop, possibly during a path search if the command is not initially found - Inside the main loop, if the call to Command::spawn() throws an error, and the error is ErrorKind::NotFound Doc comments were added for each function, as well as a few more comments throughout that detail the program's control flow. The error messages in the main repl loop were cleaned up to have a more consistent style, and to provide more/better detail. 
The 'eval' function was renamed to 'repl'.

The code to refresh the $PATH was moved into it's own function:
'prefresh', and is now being called in three locations:
  - At the beginning of 'repl', before the main loop
  - Inside the main loop, possibly during a path search if the command
    is not initially found
  - Inside the main loop, if the call to Command::spawn() throws an
    error, and the error is ErrorKind::NotFound

Doc comments were added for each function, as well as a few more
comments throughout that detail the program's control flow.

The error messages in the main repl loop were cleaned up to have a more
consistent style, and to provide more/better detail.
Better handling of errors during the fork 2024-02-19T09:33:36+00:00 Rory Dudley 2024-02-19T09:33:36+00:00 08be85a2fc508450c6361af4ef38a7dcd3efbde5 Adds two additional error checks when the shell forks: 1. Checks for permission (+r, +x) 2. Checks if the file exists The first error may occur if the user does not have read access to the file, or if the file is not executable. The second error may occur if a file was removed from the $PATH, and the $PATH hasn't been refreshed yet. 
Adds two additional error checks when the shell forks:
1. Checks for permission (+r, +x)
2. Checks if the file exists

The first error may occur if the user does not have read access to the
file, or if the file is not executable. The second error may occur if a
file was removed from the $PATH, and the $PATH hasn't been refreshed
yet.
Refresh path only if command is not found 2024-02-19T08:40:58+00:00 Rory Dudley 2024-02-19T08:40:58+00:00 2e5cc53499947c32b01ea5e1787ed505bc286969 This is a modified implementation of the 'refresh path on every iteration of the loop' idea. It instead, only refreshes the path if the command is not found. After the first refresh, if the command still is not found, it throws and error. 
This is a modified implementation of the 'refresh path on every
iteration of the loop' idea. It instead, only refreshes the path if the
command is not found. After the first refresh, if the command still is
not found, it throws and error.