dj(1): refactor source

Makefile

@@ -9,23 +9,13 @@
 # notice are preserved.  This file is offered as-is, without any warranty.
 
 .POSIX:
-
-# if using BSD make(1), remove these pragmas because they break it
 .PRAGMA: posix_202x # future POSIX standard support à la pdpmake(1)
 .PRAGMA: command_comment # breaks without this?
 
-DESTDIR ?= dist
-PREFIX ?= /usr/local
+PREFIX=/usr/local
 
-SYSEXITS != printf '\043include <sysexits.h>\n' | cpp -M - | sed 's/ /\n/g' \
-	| sed -n 's/sysexits\.h//p' || printf 'include\n'
-
-CC ?= cc
-RUSTC ?= rustc
-RUSTLIBS = --extern getopt=build/o/libgetopt.rlib \
-	--extern sysexits=build/o/libsysexits.rlib \
-	--extern strerror=build/o/libstrerror.rlib
-CFLAGS += -I$(SYSEXITS)
+CC=cc
+RUSTC=rustc
 
 .PHONY: all
 all: dj false fop hru intcmp mm npc rpn scrut str strcmp swab true
@@ -37,40 +27,36 @@ build:
 
 .PHONY: clean
 clean:
-	rm -rf build dist
+	rm -rf build/ dist/
 
 dist: all
-	mkdir -p $(DESTDIR)/$(PREFIX)/bin $(DESTDIR)/$(PREFIX)/share/man/man1
-	cp build/bin/* $(DESTDIR)/$(PREFIX)/bin
-	cp docs/*.1 $(DESTDIR)/$(PREFIX)/share/man/man1
+	mkdir -p dist/bin dist/share/man/man1
+	cp build/bin/* dist/bin/
+	cp docs/*.1 dist/share/man/man1/
 
 .PHONY: install
 install: dist
-	cp -r $(DESTDIR)/* /
+	mkdir -p $(PREFIX)
+	cp -r dist/* $(PREFIX)/
 
 .PHONY: test
 test: build
 	tests/posix-compat.sh
 	$(RUSTC) --test src/getopt-rs/lib.rs -o build/test/getopt
 
-.PHONY: rustlibs
-rustlibs: build/o/libsysexits.rlib build/o/libgetopt.rlib \
-	build/o/libstrerror.rlib
-
-build/o/libgetopt.rlib: build src/getopt-rs/lib.rs
-	$(RUSTC) $(RUSTFLAGS) --crate-type=lib --crate-name=getopt \
-		-o $@ src/getopt-rs/lib.rs
-
-build/o/libstrerror.rlib: build src/strerror.rs
-	$(RUSTC) $(RUSTFLAGS) --crate-type=lib -o $@ \
-		src/strerror.rs
-
-build/o/libsysexits.rlib: build $(SYSEXITS)sysexits.h
+build/o/libsysexits.rlib: build
 	# bandage solution until bindgen(1) gets stdin support
-	printf '#define EXIT_FAILURE 1\n' | cat - $(SYSEXITS)sysexits.h \
+	printf '#define EXIT_FAILURE 1\n' | cat - include/sysexits.h \
 		> build/include/sysexits.h 
 	bindgen --default-macro-constant-type signed --use-core --formatter=none \
-		build/include/sysexits.h | $(RUSTC) $(RUSTFLAGS) --crate-type lib -o $@ -
+		"$$(printf '#include <sysexits.h>\n' \
+			| cpp -M -idirafter "build/include" - \
+			| sed 's/ /\n/g' | grep sysexits.h)" \
+		| $(RUSTC) $(RUSTFLAGS) --crate-type lib -o build/o/libsysexits.rlib -
+
+build/o/libgetopt.rlib: src/getopt-rs/lib.rs
+	$(RUSTC) $(RUSTFLAGS) --crate-type=lib --crate-name=getopt \
+		-o build/o/libgetopt.rlib src/getopt-rs/lib.rs
 
 .PHONY: dj
 dj: build/bin/dj
@@ -84,13 +70,17 @@ build/bin/false: src/false.c build
 
 .PHONY: fop
 fop: build/bin/fop
-build/bin/fop: src/fop.rs build rustlibs
-	$(RUSTC) $(RUSTFLAGS) $(RUSTLIBS) -o $@ src/fop.rs
+build/bin/fop: src/fop.rs build build/o/libgetopt.rlib build/o/libsysexits.rlib
+	$(RUSTC) $(RUSTFLAGS) --extern getopt=build/o/libgetopt.rlib \
+		--extern sysexits=build/o/libsysexits.rlib \
+		-o $@ src/fop.rs
 
 .PHONY: hru
 hru: build/bin/hru
-build/bin/hru: src/hru.rs build rustlibs 
-	$(RUSTC) $(RUSTFLAGS) $(RUSTLIBS) -o $@ src/hru.rs
+build/bin/hru: src/hru.rs build build/o/libgetopt.rlib build/o/libsysexits.rlib
+	$(RUSTC) $(RUSTFLAGS) --extern getopt=build/o/libgetopt.rlib \
+		--extern sysexits=build/o/libsysexits.rlib \
+		-o $@ src/hru.rs
 
 .PHONY: intcmp
 intcmp: build/bin/intcmp
@@ -102,20 +92,18 @@ mm: build/bin/mm
 build/bin/mm: src/mm.c build
 	$(CC) $(CFLAGS) -o $@ src/mm.c
 
+
 .PHONY: npc
 npc: build/bin/npc
 build/bin/npc: src/npc.c build
-	$(CC) $(CFLAGS) -o $@ src/npc.c
-
-.PHONY: pg
-pg: build/bin/pg
-build/bin/pg: src/pg.c build
-	$(CC) $(CFLAGS) -o $@ src/pg.c
+	$(CC) $(CFLAGAS) -o $@ src/npc.c
 
 .PHONY: rpn
 rpn: build/bin/rpn
-build/bin/rpn: src/rpn.rs build rustlibs
-	$(RUSTC) $(RUSTFLAGS) $(RUSTLIBS) -o $@ src/rpn.rs
+build/bin/rpn: src/rpn.rs build build/o/libsysexits.rlib
+	$(RUSTC) $(RUSTFLAGS) \
+		--extern sysexits=build/o/libsysexits.rlib \
+		-o $@ src/rpn.rs
 
 .PHONY: scrut
 scrut: build/bin/scrut

docs/pg.1

@@ -1,41 +0,0 @@
-.\" Copyright (c) 2024 DTB <trinity@trinity.moe>
-.\"
-.\" This work is licensed under CC BY-SA 4.0. To see a copy of this license,
-.\" visit <http://creativecommons.org/licenses/by-sa/4.0/>.
-
-.TH PG 1
-
-.SH NAME
-
-pg \(en paginate
-
-.SH SYNOPSIS
-
-pg
-.RB ( -p
-.RB [ prompt ])
-
-.SH DESCRIPTION
-
-Pg prints standard input to standard output, accepting commands between pages.
-
-.SH OPTIONS
-
-.B -p
-.RS
-Replaces the default prompt (": ") with the next argument.
-.RE
-
-.SH DIAGNOSTICS
-
-Pg returns an unsuccessful exit code if the tty couldn't be opened or if pg was
-invoked incorrectly (with any arguments).
-
-.SH RATIONALE
-
-Plan 9 from Bell Labs had p(1), a similar "cooked"-mode paginator (as opposed
-to "raw" mode, which a vast majority of paginators use).
-
-.SH SEE ALSO
-
-more(1)

src/dj.c

@@ -46,31 +46,11 @@ struct Io{
 /* Additionally, the following global variables are used to store user options.
  */
 
-/* (-a)  */ static int align; /* Only the lower 8b are used but align is
-                               * negative if no alignment is being done. */
-
-/* (-c)  */ static int count; /* 0 if dj(1) runs until no more reads are
-                               * possible. */
-
 /* ASCII field separator delimited statistics */
-            static char *fmt_asv   = "%d\037%d\036%d\037%d\035%d\036%d\034";
-/* human-readable statistics */
-            static char *fmt_human = "%d+%d > %d+%d; %d > %d\n";
-/* pointer to chosen formatting */
-/* (-H)  */ static char *fmt_output; /* fmt_asv (default) or fmt_human (-H) */
+static char *fmt_asv   = "%d\037%d\036%d\037%d\035%d\036%d\034";
 
-/* (-dq) */ static char debug;       /*
- *  -d  increments             dj -qq | 0 - no diagnostic output whatsoever
- *   -q decrements             dj -q  | 1 - typical output without
- *                                    |     notifications on partial reads or
- *                                    |     writes
- *                             dj     | 2 - typical output (default)
- *                             dj -d  | 3 - verbose status messages */
-
-/* (-n)  */ static char noerror;     /* 0 - exits on partial reads or writes
-                                      *     (default)
-                                      * 1 - retries on partial reads/writes
-                                      *     (-n) */
+/* (-H) Human-readable statistics */
+static char *fmt_human = "%d+%d > %d+%d; %d > %d\n";
 
 /* Non-configurable defaults. */
 #define bs_default 1024 /* GNU dd(1) default; twice POSIX but a neat 2^10 */
@@ -80,19 +60,8 @@ static char *stdout_name = "<stdout>";
 static int read_flags = O_RDONLY; /* These flags are consistent with Busybox */
 static int write_flags = O_WRONLY | O_CREAT; /* dd(1). */
 
-/* Macro to set defaults for user-configurable options. */
-#define setdefaults do{ \
-	align = -1; \
-	count = 0; \
-	debug = 2; \
-	fmt_output = fmt_asv; \
-	noerror = 0; \
-	ep[0].fl = read_flags; \
-	Io_setdefaults(&ep[0]); \
-	ep[1].fl = write_flags; \
-	Io_setdefaults(&ep[1]); }while(0)
-
 #define MIN(a, b) (((a) < (b)) ? (a) : (b))
+#define MAX(a, b) (((a) > (b)) ? (a) : (b))
 
 /* Macro to check if fd is a std* file, e.g. stdin. */
 #define fdisstd(fd) \
@@ -104,43 +73,16 @@ static int write_flags = O_WRONLY | O_CREAT; /* dd(1). */
  * particular io[2] used in main. Error conditions are not checked because this
  * is only used when the program is about to terminate (hence its name). */
 #define terminate(io) do{ \
-	Io_buffree(&(io)[0]); \
-	Io_buffree(&(io)[1]); \
+	free((io)[0].buf); \
+	free((io)[1].buf); \
 	Io_fdclose(&(io)[0]); \
 	Io_fdclose(&(io)[1]); }while(0)
 
-/* Allocates *io's buffer. Returns NULL if unsuccessful. */
-static void *
-Io_bufalloc(struct Io *io){
-
-	return (io->buf = malloc(io->bs * (sizeof *io->buf)));
-}
-
-/* Frees *io's buffer. Returns io. */
-static struct Io *
-Io_buffree(struct Io *io){
-
-	free(io->buf);
-
-	return io;
-}
-
-/* Fills the unused portion of io's buffer with padding, updating io->bufuse.
- * Returns io. */
-static struct Io *
-Io_bufrpad(struct Io *io, int padding){
-	
-	memset(io->buf + io->bufuse, padding, io->bs - io->bufuse);
-	io->bufuse = io->bs;
-
-	return io;
-}
-
 /* Copies from the buffer in src as much as possible to the free space in the
  * dest buffer, removing the copied units from src and permuting the remaining
  * units in the src buffer to the start of the buffer, modifying both the src
  * and dest bufuse and returning dest. */
-static struct Io*
+static struct Io *
 Io_bufxapp(struct Io *dest, struct Io *src){
 	int n;
 
@@ -157,7 +99,7 @@ Io_bufxapp(struct Io *dest, struct Io *src){
  * removing the copied units from src and permuting the remaining units in the
  * src buffer to the start of the buffer, modifying both the src and dest
  * bufuse and returning dest. */
-static struct Io*
+static struct Io *
 Io_bufxfer(struct Io *dest, struct Io *src, int n){
 
 	memcpy(dest->buf, src->buf, (dest->bufuse = n));
@@ -167,13 +109,10 @@ Io_bufxfer(struct Io *dest, struct Io *src, int n){
 }
 
 /* Closes io->fn and returns -1 on error, otherwise io->fd. */
-static int
-Io_fdclose(struct Io *io){
-
-	return fdisstd(io->fd)
-		? 0
-		: close(io->fd);
-}
+#define Io_fdclose(io) \
+	(fdisstd((io)->fd) \
+		? 0 \
+		: close((io)->fd))
 
 /* Opens io->fn and saves the file descriptor into io->fd. Returns io->fd,
  * which will be -1 if an error occured. */
@@ -199,7 +138,6 @@ Io_fdopen(struct Io *io, char *fn){
  * be set to zero to indicate the seek occurred. */
 static int
 Io_fdseek(struct Io *io){
-	int (*op)(int, void *, size_t);
 
 	if(!fdisstd(io->fd) && lseek(io->fd, io->seek, SEEK_SET) != -1)
 		return -1;
@@ -283,19 +221,6 @@ oserr(char *s){
 	return EX_OSERR;
 }
 
-/* Prints statistics regarding the use of dj, particularly partially and
- * completely read and written records, accessing debug, ep, and fmt_output. */
-static void
-output(void){
-
-	if(debug >= 1)
-		fprintf(stderr, fmt_output,
-			ep[0].rec, ep[0].prec, ep[1].rec, ep[1].prec,
-			ep[0].bytes, ep[1].bytes);
-
-	return;
-}
-
 /* Parses the string s to an integer, returning either the integer or in the
  * case of an error a negative integer. This is used for argument parsing
  * (e.g. -B [int]) in dj and no negative integer would be valid anyway. */
@@ -321,11 +246,30 @@ usage(void){
 	return EX_USAGE;
 }
 
-int main(int argc, char *argv[]){
-	int c;
-	int i;
+/* For use in main only.
+ * Prints statistics regarding the use of dj, particularly partially and
+ * completely read and written records, accessing ep, and fmt_output. */
+#define output fprintf(stderr, fmt_output, \
+	ep[0].rec, ep[0].prec, ep[1].rec, ep[1].prec, ep[0].bytes, ep[1].bytes \
+)
 
-	setdefaults;
+int main(int argc, char *argv[]){
+	int align; /* Only the lower 8b are used, negative if no alignment. */
+	int count;
+	int c, i;
+	enum { QUIETER = 0, TYPICAL = 1, VERBOSE = 2 } debug;
+	enum { GIVEUP = 0, RETRY = 1 } error;
+	char *fmt_output = fmt_asv;
+
+	ep[0].fl = read_flags;
+	Io_setdefaults(&ep[0]);
+	ep[1].fl = write_flags;
+	Io_setdefaults(&ep[1]);
+
+	align = -1;
+	count = 0;
+	debug = TYPICAL;
+	error = GIVEUP;
 
 	if(argc > 0){
 		program_name = argv[0];
@@ -342,10 +286,10 @@ int main(int argc, char *argv[]){
 				terminate(ep);
 				return oserr(optarg);
 			case 'A': align = '\0'; break;
-			case 'd': ++debug; break;
-			case 'n': noerror = 1; break;
+			case 'd': debug = VERBOSE; break;
+			case 'n': error = RETRY; break;
 			case 'H': fmt_output = fmt_human; break;
-			case 'q': --debug; break;
+			case 'q': debug = QUIETER; break;
 			case 'a':
 				if(optarg[0] != '\0' && optarg[1] == '\0'){
 					align = optarg[0];
@@ -367,14 +311,15 @@ int main(int argc, char *argv[]){
 			}
 	}
 
-	if(debug >= 3)
+	if(debug >= VERBOSE)
 		fprintf(stderr,
 			"argv0=%s\n"
 			"in=%s\tibs=%d\tskip=%ld\talign=%hhx\tcount=%d\n"
-			"out=%s\tobs=%d\tseek=%ld\tdebug=%2d\tnoerror=%d\n",
+			"out=%s\tobs=%d\tseek=%ld\tdebug=%2d\terror=%s\n",
 			program_name,
 			ep[0].fn, ep[0].bs, ep[0].seek, align, count,
-			ep[1].fn, ep[1].bs, ep[1].seek, debug, noerror);
+			ep[1].fn, ep[1].bs, ep[1].seek, debug,
+		    error == GIVEUP ? "GIVEUP" : "RETRY");
 
 	if(argc > optind){
 		terminate(ep);
@@ -382,36 +327,37 @@ int main(int argc, char *argv[]){
 	}
 
 	for(i = 0; i <= 1; ++i){
-		if(Io_bufalloc(&ep[i]) == NULL){
+		if((ep[i].buf = malloc(ep[i].bs * (sizeof ep[i].buf))) == NULL){
 			fprintf(stderr, "%s: Failed to allocate %d bytes\n",
-				program_name, ep[i].bs);
+				program_name, ep[i].bs * (sizeof ep[i].buf));
 			terminate(ep);
 			return EX_OSERR;
-		}else if(ep[i].seek > 0)
-			switch(Io_fdseek(&ep[i])){
-			case EX_OK:
-				output();
+		}else if(ep[i].seek > 0 && (c = Io_fdseek(&ep[i])) != -1){
+			output;
 			terminate(ep);
-				return EX_OK;
+			return c;
 		}
 	}
 
 	do{	/* read */
 		Io_read(&ep[0]);
-		if(!noerror && ep[0].bufuse == 0)
+		if(error == RETRY && ep[0].bufuse == 0)
 			Io_read(&ep[0]); /* second chance */
 		if(ep[0].bufuse == 0) /* that's all she wrote */
 			break;
 		else if(ep[0].bufuse < ep[0].bs){
 			++ep[0].prec;
-			if(debug >= 2){
+			if(debug >= TYPICAL){
 				fprintf(stderr, "%s: Partial read:\n\t", program_name);
-				output();
+				output;
 			}
-			if(!noerror)
+			if(error == GIVEUP)
 				count = 1;
-			if(align >= 0)
-				Io_bufrpad(&ep[0], align);
+			if(align >= 0){
+				memset(ep[0].buf + ep[0].bufuse, align,
+					ep[0].bs - ep[0].bufuse);
+				ep[0].bufuse = ep[0].bs;
+			}
 		}else
 			++ep[0].rec;
 
@@ -425,18 +371,18 @@ int main(int argc, char *argv[]){
 
 			c = ep[1].bufuse;
 			Io_write(&ep[1]);
-			if(!noerror && ep[1].bufuse == c)
+			if(error == GIVEUP && ep[1].bufuse == c)
 				Io_write(&ep[1]); /* second chance */
 			if(c == ep[1].bufuse){ /* no more love */
 				count = 1;
 				break;
 			}else if(c > ep[1].bufuse && ep[1].bufuse > 0){
 				ep[1].prec += 1;
-				if(debug >= 2){
+				if(debug >= TYPICAL){
 					fprintf(stderr, "%s: Partial write:\n\t", program_name);
-					output();
+					output;
 				}
-				if(!noerror)
+				if(error == GIVEUP)
 					count = 1;
 			}else if(ep[1].bufuse == 0 && c < ep[1].bs)
 				++ep[1].prec;
@@ -445,7 +391,7 @@ int main(int argc, char *argv[]){
 		}while(ep[0].bufuse > 0);
 	}while(count == 0 || --count > 0);
 
-	output();
+	output;
 	terminate(ep);
 
 	return EX_OK;

src/fop.rs

@@ -22,12 +22,10 @@ use std::{
 	process::{ Command, exit, Stdio },
 };
 
-extern crate getopt;
-extern crate strerror;
 extern crate sysexits;
+extern crate getopt;
 
 use getopt::{ Opt, Parser };
-use strerror::StrError;
 use sysexits::{ EX_DATAERR, EX_IOERR, EX_UNAVAILABLE, EX_USAGE };
 
 fn main() {
@@ -57,7 +55,7 @@ fn main() {
 	});
 
 	let index = argv[index_arg].parse::<usize>().unwrap_or_else(|e| {
-		eprintln!("{}: {}: {}", argv[0], argv[1], e);
+		eprintln!("{}: {}: {}.", argv[0], argv[1], e);
 		exit(EX_DATAERR);
 	});
 
@@ -77,13 +75,13 @@ fn main() {
 		.stdout(Stdio::piped())
 		.spawn()
 		.unwrap_or_else( |e| {
-			eprintln!("{}: {}: {}", argv[0], argv[command_arg], e.strerror());
+			eprintln!("{}: {}: {}.", argv[0], argv[command_arg], e);
 			exit(EX_UNAVAILABLE);
 		});
 
 	let field = fields.get(index).unwrap_or_else(|| {
 		eprintln!(
-			"{}: {}: No such index in input",
+			"{}: {}: No such index in input.",
 			argv[0],
 			index.to_string(),
 		);
@@ -96,7 +94,7 @@ fn main() {
 	}
 
 	let output = spawned.wait_with_output().unwrap_or_else(|e| {
-		eprintln!("{}: {}: {}", argv[0], argv[command_arg], e.strerror());
+		eprintln!("{}: {}: {}.", argv[0], argv[command_arg], e);
 		exit(EX_IOERR);
 	});
 
@@ -105,7 +103,7 @@ fn main() {
 	if replace.pop() != Some(b'\n') { replace = output.stdout; }
 
 	let new_field = String::from_utf8(replace).unwrap_or_else(|e| {
-		eprintln!("{}: {}: {}", argv[0], argv[command_arg], e);
+		eprintln!("{}: {}: {}.", argv[0], argv[command_arg], e);
 		exit(EX_IOERR);
 	});
 
@@ -113,8 +111,8 @@ fn main() {
 
 	stdout().write_all(
 		fields.join(&d.to_string()).as_bytes()
-	).unwrap_or_else(|e| {
-		eprintln!("{}: {}", argv[0], e.strerror());
+	).unwrap_or_else(|e|{
+		eprintln!("{}: {}.", argv[0], e);
 		exit(EX_IOERR);
 	});
 }

src/hru.rs

@@ -23,10 +23,8 @@ use std::{
 	process::{ ExitCode, exit },
 };
 
-extern crate strerror;
 extern crate sysexits;
 
-use strerror::StrError;
 use sysexits::{ EX_DATAERR, EX_IOERR, EX_SOFTWARE };
 
 const LIST: [(u32, &str); 10] = [
@@ -51,7 +49,7 @@ fn convert(input: u128) -> Result<(f64, (u32, &'static str)), String> {
 		let c = match 10_u128.checked_pow(n) {
 			Some(c) => c,
 			None => {
-				return Err(format!("10^{}: Integer overflow", n.to_string()));
+				return Err(format!("10^{}: Integer overflow.", n.to_string()));
 			},
 		};
 
@@ -81,7 +79,7 @@ fn main() -> ExitCode {
 				f
 			},
 			Err(err) => {
-				eprintln!("{}: {}", argv[0], err);
+				eprintln!("{}: {}.", argv[0], err);
 				return ExitCode::from(EX_DATAERR as u8);
 			},
 		};
@@ -89,7 +87,7 @@ fn main() -> ExitCode {
 		let (number, prefix) = match convert(n) {
 			Ok(x) => x,
 			Err(err) => {
-				eprintln!("{}: {}", argv[0], err);
+				eprintln!("{}: {}.", argv[0], err);
 				return ExitCode::from(EX_SOFTWARE as u8);
 			},
 		};
@@ -100,7 +98,7 @@ fn main() -> ExitCode {
 
 		stdout().write_all(format!("{} {}\n", out, si_prefix).as_bytes())
 			.unwrap_or_else(|e| {
-				eprintln!("{}: {}", argv[0], e.strerror());
+				eprintln!("{}: {}.", argv[0], e);
 				exit(EX_IOERR);
 			});
 	}

src/pg.c

@@ -1,260 +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 <stdio.h> /* fclose(3), feof(3), fgetc(3), fgets(3), fopen(3),
-                    * fprintf(3), fputc(3), stderr, stdin, stdout, EOF, FILE,
-                    * NULL */
-#include <stdlib.h> /* size_t */
-#include <string.h> /* strchr(3), strcmp(3), strerror(3), strtok(3) */
-#include <unistd.h> /* getopt(3) */
-
-/* Commands start with cmd_. They take an argc and NULL-terminated argv, like
- * main, and return a status from <sysexits.h>. Return values other than EX_OK
- * and EX_USAGE cause pg(1) to exit with that value, except EX_UNAVAILABLE,
- * which causes pg(1) to exit with the status EX_OK. */
-#include <sysexits.h>
-
-#define CMDLINE_MAX 99+1 /* Maximum length of command line. */
-
-static char *whitespace = " \n\r\t\v";
-
-static struct {
-	size_t quantity;
-	enum { LINES = 0, BYTES = 1 } type;
-} default_page_unit = { 22, LINES } /* Plan 9 default */;
-static FILE *input;
-static char *prompt = ": ";
-static char *program_name = "pg";
-
-static char *permute_out(char *str, size_t index){
-	size_t j;
-
-	for(j = index; str[j - 1] != '\0'; ++j)
-		str[j - 1] = str[j];
-
-	return str;
-}
-
-/* strtok(3p), but supports double-quotes and escapes (but only for escaping
- * quotes). UTF-8 is safe only in str. Unmatched quotes in str are considered
- * literal. The behavior of strtok_quoted when '"' or '\\' are in sep is
- * undefined. */
-/* TODO: Seems to only ever return NULL. */
-static char *strtok_quoted(char *str, char *sep){
-	static char *s;
-	size_t i;
-	size_t j;
-
-	if(str != NULL)
-		s = str;
-
-	while(strchr(sep, *s) == NULL)
-		if(*++s == '\0')
-			return NULL; /* no remaining characters except seperators */
-
-	{
-		char in_escape;
-		int in_quotes;
-
-		in_escape = 0;
-		in_quotes = -1;
-		for(i = 0; s[i] != '\0'; ++i)
-			switch(s[i]){
-			case '\\':
-				if(in_escape)
-					permute_out(s, i--);
-				in_escape = !in_escape;
-				break;
-			case '"':
-				if(in_escape){
-					s[i] = s[i - 1];
-					permute_out(s, i--);
-				}else if(in_quotes != -1){
-					permute_out(s, in_quotes);
-					--i;
-					permute_out(s, i--);
-					in_quotes = -1;
-				}else
-					in_quotes = i;
-				break;
-			case '\0':
-				return s;
-			default:
-				if(!in_escape && strchr(sep, s[i]) != NULL){
-					s[i] = '\0';
-					return s;
-				}
-			}
-	}
-
-	return s;
-}
-
-/* Page at most l bytes from f without consideration of a buffer (print them to
- * stdout). */
-static int pg_b_u(FILE *f, size_t l){
-	int c;
-
-	while((c = fgetc(f)) != EOF)
-		if((c = fputc(c, stdout)) == EOF || --l == 0)
-			break;
-
-	return c;
-}
-
-/* Page at most l lines, which are lengths of characters terminated by nl, from
- * f without consideration of a buffer (print them to stdout). */
-static int pg_l_u(FILE *f, size_t l, char nl){
-	int c;
-
-	while((c = fgetc(f)) != EOF)
-		if((c = fputc(c, stdout)) == EOF || (l -= (c == nl)) == 0)
-			break;
-
-	return c;
-}
-
-static int cmd_quit(int argc, char **argv, char **envp){return EX_UNAVAILABLE;}
-static int cmd_default_page(int argc, char **argv, char **envp){
-
-	if(argc > 1) /* This shouldn't be possible. */
-		return EX_USAGE;
-	if(default_page_unit.type == BYTES)
-		return pg_b_u(input, default_page_unit.quantity) == EOF
-			? EX_UNAVAILABLE
-			: EX_OK;
-	else if(default_page_unit.type == LINES)
-		return pg_l_u(input, default_page_unit.quantity, '\n') == EOF
-			? EX_UNAVAILABLE
-			: EX_OK;
-	else
-		return EX_SOFTWARE;
-}
-static int cmd_page_down_lines(int argc, char **argv, char **envp){
-
-	switch(argc){
-	case 1:
-		return cmd_default_page(argc, argv, envp);
-	case 2: /* not implemented */
-	default:
-		fprintf(stderr, "Usage: %s" /*" (lines)"*/ "\n", argv[0]);
-		return EX_USAGE;
-	}
-}
-
-/* A CmdMap must be NULL-terminated. */
-static struct CmdMap{ char *name; int (*fn)(int, char **, char **); }
-builtins[] = {
-	{ "", cmd_default_page },
-	{ "+", cmd_page_down_lines },
-
-	/* don't make the user feel trapped */
-	{ ":q", cmd_quit }, { ":q!", cmd_quit },
-	{ "exit", cmd_quit }, { "q", cmd_quit }, { "Q", cmd_quit },
-	{ "quit", cmd_quit }, { "ZZ", cmd_quit },
-	
-	{ NULL, NULL }
-};
-
-#define ARGV_MAX 10
-/* Find and execute the command in the command map, given a corresponding
- * command line. */
-static int cmdline_exec(struct CmdMap *map, char *cmdline, char **envp){
-	/* Command line word splitting is naive and based on whitespace ONLY; no
-	 * fancy quoting or escaping here. Adding that would (ideally) entail
-	 * replacing strtok(3) with something specific to this task. */
-	static int argc;
-	static char *argv[ARGV_MAX];
-
-	if((argv[(argc = 0)] = strtok(cmdline, whitespace)) == NULL){
-		while(cmdline[0] != '\0')
-			cmdline = &cmdline[1];
-		argv[argc] = cmdline;
-		argv[++argc] = NULL;
-	}else{
-		while((argv[++argc] = strtok(NULL, whitespace)) != NULL
-		      && argc < ARGV_MAX);
-	}
-
-	for(; map->name != NULL; map = &map[1])
-		if(strcmp(map->name, argv[0]) == 0)
-			return map->fn(argc, argv, envp);
-
-	fprintf(stderr, "%s: %s: not found\n", program_name, argv[0]);
-	return EX_USAGE;
-}
-
-int usage(char *s){
-	fprintf(stderr, "Usage: %s (-p [prompt])\n", s);
-	return EX_USAGE;
-}
-
-int main(int argc, char *argv[]){
-	unsigned char cmd[CMDLINE_MAX];
-	FILE *t;
-
-	input = stdin;
-
-	if(argc < 1)
-		program_name = argv[0];
-	else{
-		int c;
-
-		while((c = getopt(argc, argv, "p:")) != -1)
-			switch(c){
-			case 'p': prompt = optarg; break;
-			default:
-				return usage(program_name);
-			}
-	}
-
-	if(argc > optind)
-		return usage(program_name);
-
-
-	if((t = fopen("/dev/tty", "rb")) == NULL){
-		fprintf(stderr, "%s: /dev/tty: %s\n", program_name, strerror(errno));
-		return EX_OSERR;
-	}
-
-	for(;;){
-		fputs(prompt, stderr);
-		fgets((char *)cmd, (sizeof cmd) / (sizeof *cmd), t);
-		if(strchr((char *)cmd, '\n') == NULL){ /* fast-forward stream */
-			int c;
-
-			while((c = fgetc(t)) != '\n')
-				if(c == EOF)
-					break;
-		}
-
-		if(feof(t))
-			return EX_OK;
-
-		{	int r;
-			switch((r = cmdline_exec(builtins, (char *)cmd, NULL))){
-			case EX_OK: case EX_USAGE: break;
-			case EX_UNAVAILABLE: return EX_OK;
-			default: return r;
-		}	}
-	}
-
-	/* UNREACHABLE */
-	return EX_SOFTWARE;
-}

src/rpn.rs

@@ -172,7 +172,7 @@ fn eval(
 					};
 				} else {
 					return Err(EvaluationError {
-						message: format!("{}: Unexpected operation", op),
+						message: format!("{}: Unexpected operation.", op),
 						code: EX_DATAERR,
 					})
 				}

src/strerror.rs

@@ -1,31 +0,0 @@
-/*
- * Copyright (c) 2024 Emma Tebibyte <emma@tebibyte.media>
- * SPDX-License-Identifier: FSFAP
- *
- * Copying and distribution of this file, with or without modification, are
- * permitted in any medium without royalty provided the copyright notice and
- * this notice are preserved.  This file is offered as-is, without any warranty.
- */
-
-use std::ffi::{ c_int, c_char, CStr };
-
-pub trait StrError { fn strerror(&self) -> String; }
-
-impl StrError for std::io::Error {
-	/* wrapper function for use in Rust */
-	fn strerror(&self) -> String {
-		/* Get the raw OS error. If it’s None, what the hell is going on‽ */
-		let errno = self.raw_os_error().unwrap_or(0) as c_int;
-
-		/* Get a CStr from the error message so that it’s referenced and then
-		 * convert it to an owned value. If the string is not valid UTF-8,
-		 * return that error instead. */
-		match unsafe { CStr::from_ptr(strerror(errno)) }.to_str() {
-			Ok(s) => s.to_owned(), // yay!! :D
-			Err(e) => e.to_string(), // awww :(
-		}
-	}
-}
-
-/* binding to strerror(3p) */
-extern "C" { fn strerror(errnum: c_int) -> *mut c_char; }

src/test.rs

@@ -1,10 +0,0 @@
-extern crate strerror;
-
-use strerror::raw_message;
-
-fn main() {
-	stdout.write_all(b"meow\n").unwrap_or_else(|e| {
-		eprintln!("{}", raw_message(e));
-		std::process::exit(1);
-	});
-}