mm(1): rewritten in Rust

This commit is contained in:
Emma Tebibyte 2024-07-13 23:49:27 -06:00
parent 9addfc9284
commit 1b3b03cae0
Signed by untrusted user: emma
GPG Key ID: 06FA419A1698C270
3 changed files with 139 additions and 238 deletions

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@ -114,8 +114,8 @@ build/bin/intcmp: src/intcmp.c build
.PHONY: mm
mm: build/bin/mm
build/bin/mm: src/mm.c build
$(CC) $(CFLAGS) -o $@ src/mm.c
build/bin/mm: src/mm.rs build rustlibs
$(RUSTC) $(RUSTFLAGS) $(RUSTLIBS) -o $@ src/mm.rs
.PHONY: npc
npc: build/bin/npc

236
src/mm.c
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@ -1,236 +0,0 @@
/*
* Copyright (c) 2024 DTB <trinity@trinity.moe>
* SPDX-License-Identifier: AGPL-3.0-or-later
*
* This program is free software: you can redistribute it and/or modify it under
* the terms of the GNU Affero General Public License as published by the Free
* Software Foundation, either version 3 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 Affero General Public License for more
* details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see https://www.gnu.org/licenses/.
*/
#include <errno.h> /* errno */
#include <signal.h> /* signal(2), SIG_ERR, SIG_IGN, SIGINT */
#include <stdio.h> /* fclose(3), fopen(3), fprintf(3), getc(3), putc(3),
* setvbuf(3), size_t, _IONBF, NULL */
#include <stdlib.h> /* free(3), realloc(3) */
#include <string.h> /* strcmp(3), strerror(3) */
#include <unistd.h> /* getopt(3) */
#if !defined EX_IOERR || !defined EX_OK || !defined EX_OSERR \
|| !defined EX_USAGE
# include <sysexits.h>
#endif
extern int errno;
/* This structure is how open files are tracked. */
struct Files{
size_t a; /* allocation */
size_t s; /* used size */
char *mode; /* file opening mode */
char **names; /* file names */
FILE **files; /* file pointers */
};
/* How much to grow the allocation when it's saturated. */
#ifndef ALLOC_INCREMENT
# define ALLOC_INCREMENT 1
#endif
/* How much to grow the allocation at program start. */
#ifndef ALLOC_INITIAL
# define ALLOC_INITIAL 10
#endif
/* pre-allocated strings */
static char *program_name = "<no argv[0]>";
static char *stdin_name = "<stdin>";
static char *stdout_name = "<stdout>";
static char *stderr_name = "<stderr>";
static char *(fmode[]) = { (char []){"rb"}, (char []){"rb+"} };
static char *wharsh = "wb";
/* Adds the open FILE pointer for the file at the path s to the files struct,
* returning the FILE if successful and NULL if not, allocating more memory in
* the files buffers as needed. */
static FILE *
Files_append(struct Files *files, FILE *file, char *name){
if(file == NULL || (files->s == files->a
&& ((files->files = realloc(files->files,
(files->a += (files->a == 0)
? ALLOC_INITIAL
: ALLOC_INCREMENT)
* sizeof *(files->files))) == NULL
|| (files->names = realloc(files->names,
files->a * sizeof *(files->names))) == NULL)))
return NULL;
files->names[files->s] = name;
return files->files[files->s++] = file;
}
/* Opens the file at the path p and puts it in the files struct, returning NULL
* if either the opening or the placement of the open FILE pointer fail. */
#define Files_open(files, p) \
Files_append((files), fopen((p), (files)->mode), (p))
/* Prints a diagnostic message based on errno and returns an exit status
* appropriate for an OS error. */
static int
oserr(char *s, char *r){
fprintf(stderr, "%s: %s: %s\n", s, r, strerror(errno));
return EX_OSERR;
}
/* Hijacks i and j from main and destructs the files[2] struct used by main by
* closing its files and freeing its files and names arrays, returning retval
* from main. */
#define terminate \
for(i = 0; i < 2; ++i){ \
for(j = 0; j < files[i].s; ++j) \
if(files[i].files[j] != stdin \
&& files[i].files[j] != stdout \
&& files[i].files[j] != stderr) \
fclose(files[i].files[j]); \
free(files[i].files); \
free(files[i].names); \
} \
return retval
/* Prints a usage text, in which s is the program being run (i.e. argv[0]), and
* returns an exit status appropriate for a usage error. */
int usage(char *s){
fprintf(stderr, "Usage: %s [-aenu] [-i input]... [-o output]...\n", s);
return EX_USAGE;
}
int main(int argc, char *argv[]){
int c;
struct Files files[2]; /* {read, write} */
size_t i;
size_t j;
size_t k; /* loop index but also unbuffer status */
int retval;
/* Initializes the files structs with their default values, standard
* input and standard output. If an input or an output is specified
* these initial values will be overwritten, so to, say, use mm(1)
* equivalently to tee(1p), -o - will need to be specified before
* additional files to ensure standard output is still written. */
for(i = 0; i < 2; ++i){
files[i].a = 0;
files[i].s = 0;
files[i].mode = fmode[i];
files[i].files = NULL;
files[i].names = NULL;
Files_append(&files[i], i == 0 ? stdin : stdout,
i == 0 ? stdin_name : stdout_name);
files[i].s = 0;
}
k = 0;
if(argc > 0)
program_name = argv[0];
if(argc > 1)
while((c = getopt(argc, argv, "aehi:no:u")) != -1)
switch(c){
case 'a': /* "rb+" -> "ab" */
files[1].mode[0] = 'a';
files[1].mode[2] = '\0';
break;
case 'e':
if(Files_append(&files[1], stderr, stderr_name) != NULL)
break;
retval = oserr(argv[0], "-e");
terminate;
case 'i':
if((strcmp(optarg, "-") == 0 && Files_append(&files[0],
stdin, stdin_name) != NULL)
|| Files_open(&files[0], optarg) != NULL)
break;
retval = oserr(argv[0], optarg);
terminate;
case 'o':
if((strcmp(optarg, "-") == 0 && Files_append(&files[1],
stdout, stdout_name) != NULL)
|| Files_open(&files[1], optarg) != NULL)
break;
/* does not exist, so try to create it */
if(errno == ENOENT){
files[1].mode = wharsh;
if(Files_open(&files[1], optarg) != NULL){
files[1].mode = fmode[1];
break;
}
}
retval = oserr(argv[0], optarg);
terminate;
case 'n':
if(signal(SIGINT, SIG_IGN) != SIG_ERR)
break;
retval = oserr(argv[0], "-n");
terminate;
case 'u':
k = 1;
break;
default:
retval = usage(argv[0]);
terminate;
}
if(optind != argc){
retval = usage(argv[0]);
terminate;
}
files[0].s += files[0].s == 0;
files[1].s += files[1].s == 0;
/* Unbuffer files. */
if(k){
for(i = 0;
i < files[0].s;
setvbuf(files[0].files[i++], NULL, _IONBF, 0));
for(i = 0;
i < files[1].s;
setvbuf(files[1].files[i++], NULL, _IONBF, 0));
}
retval = EX_OK;
/* Actual program loop. */
for(i = 0; i < files[0].s; ++i) /* iterate ins */
while((c = getc(files[0].files[i])) != EOF) /* iterate chars */
for(j = 0; j < files[1].s; ++j) /* iterate outs */
if(putc(c, files[1].files[j]) == EOF){
/* notebook's full */
retval = EX_IOERR;
fprintf(stderr, "%s: %s: %s\n",
program_name, files[1].names[j], strerror(errno));
if(fclose(files[1].files[j]) == EOF)
fprintf(stderr, "%s: %s: %s\n",
program_name, files[1].names[j], strerror(errno));
/* massage out the tense muscle */
for(k = j--; k < files[1].s - 1; ++k){
files[1].files[k] = files[1].files[k+1];
files[1].names[k] = files[1].names[k+1];
}
if(--files[1].s == 0)
terminate;
}
terminate;
}

137
src/mm.rs Normal file
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@ -0,0 +1,137 @@
/*
* Copyright (c) 2024 Emma Tebibyte <emma@tebibyte.media>
* SPDX-License-Identifier: AGPL-3.0-or-later
*
* This program is free software: you can redistribute it and/or modify it under
* the terms of the GNU Affero General Public License as published by the Free
* Software Foundation, either version 3 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 Affero General Public License for more
* details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see https://www.gnu.org/licenses/.
*/
use std::{
env::args,
fs::File,
io::{ stdin, stdout, stderr, BufWriter, Read, Write },
os::fd::{ AsRawFd, FromRawFd },
process::{ exit, ExitCode },
};
extern crate getopt;
extern crate strerror;
extern crate sysexits;
use getopt::GetOpt;
use strerror::StrError;
use sysexits::{ EX_IOERR, EX_USAGE };
fn main() -> ExitCode {
let argv = args().collect::<Vec<_>>();
let usage = format!("Usage: {} [-aeu] [-i input] [-o output]", argv[0]);
let mut a = false; /* append rather than update */
let mut e = false; /* use stderr as an output */
let mut u = false; /* unbuffer i/o */
let mut ins = Vec::new(); /* initial inputs vector */
let mut outs = Vec::new(); /* initial outputs vector */
while let Some(opt) = argv.getopt("aei:o:u") {
match opt.opt() {
Ok("a") => a = true,
Ok("e") => e = true,
Ok("u") => u = true,
Ok("i") => { /* add input */
let input = opt.arg().unwrap();
ins.push(input);
},
Ok("o") => { /* add output */
let output = opt.arg().unwrap();
outs.push(output);
},
Err(_) | Ok(_) => {
eprintln!("{}", usage);
return ExitCode::from(EX_USAGE as u8);
},
};
}
/* use stdin if no inputs are specified */
if ins.is_empty() { ins.push("-".to_string()); }
/* use stdout if no outputs are specified */
if outs.is_empty() { outs.push("-".to_string()); }
/* map all path strings to files */
let inputs = ins.iter().map(|file| {
/* if a file is “-”, it is stdin */
if *file == "-" {
return unsafe { File::from_raw_fd(stdin().as_raw_fd()) }; /* fd0 = stdin */
}
match File::options().append(a).open(file) {
Ok(f) => f,
Err(e) => {
eprintln!("{}: {}", argv[0], e.strerror());
exit(EX_IOERR);
},
}
}).collect::<Vec<_>>();
/* map all path strings to files */
let mut outputs = outs.iter().map(|file| {
/* of a file is “-”, it is stdout */
if *file == "-" {
return unsafe { File::from_raw_fd(stdout().as_raw_fd()) }; /* fd1 = stdout */
}
match File::options().append(a).open(file) {
Ok(f) => return f,
Err(e) => {
eprintln!("{}: {}", argv[0], e.strerror());
exit(EX_IOERR);
},
};
}).collect::<Vec<_>>();
/* if -e is specified, use stderr */
if e {
outputs.push(unsafe { File::from_raw_fd(stderr().as_raw_fd()) }); /* fd2 = stderr */
}
let mut outputs = outputs.iter().map(|o| {
if u {
BufWriter::with_capacity(0, o)
} else {
BufWriter::new(o)
}
}).collect::<Vec<_>>();
for file in inputs {
for byte in file.bytes().map(|b| {
b.unwrap_or_else(|e| {
eprintln!("{}: {}", argv[0], e.strerror());
exit(EX_IOERR);
})
}) {
for out in &mut outputs {
if let Err(e) = out.write(&[byte]) {
eprintln!("{}: {}", argv[0], e.strerror());
return ExitCode::from(EX_IOERR as u8);
}
if let Err(e) = out.flush() {
eprintln!("{}: {}", argv[0], e.strerror());
return ExitCode::from(EX_IOERR as u8);
}
}
}
}
ExitCode::SUCCESS
}