cat.phs

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// Port of 'cat' - concatenate files and print on the standard output for GNU.
// 'cat' file concatenation program for Phasor.
//   Copyright (C) 2026 Daniel McGuire.
//
//   This program is free software: you can redistribute it and/or modify
//   it under the terms of the GNU 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 General Public License for more details.
//
//   You should have received a copy of the GNU General Public License
//   along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
// Include standard libraries
include_stdio();
include_stdfile();
include_stdsys();
include_stdstr();
 
// Global variables for options
var g_show_all = false;        // -A, --show-all
var g_number_nonblank = false; // -b, --number-nonblank
var g_show_ends = false;       // -e, -E, --show-ends
var g_number = false;          // -n, --number
var g_squeeze_blank = false;   // -s, --squeeze-blank
var g_show_tabs = false;       // -t, -T, --show-tabs
var g_show_nonprinting = false; // -v, --show-nonprinting
 
// Line number counter
var g_line_number = 1;
 
fn startsWith(input: string, prefix: string) {
    if (len(input) < len(prefix)) return false;
    return substr(input, 0, len(prefix)) == prefix;
}
 
// Function to display help message
fn show_help() -> void {
    puts("Usage: cat [OPTION]... [FILE]...");
    puts("Concatenate FILE(s) to standard output.");
    puts("");
    puts("With no FILE, or when FILE is -, read standard input.");
    puts("");
    puts("Options:");
    puts("  -A, --show-all           equivalent to -vET");
    puts("  -b, --number-nonblank    number nonempty output lines, overrides -n");
    puts("  -e                       equivalent to -vE");
    puts("  -E, --show-ends          display $ at end of each line");
    puts("  -n, --number             number all output lines");
    puts("  -s, --squeeze-blank      suppress repeated empty output lines");
    puts("  -t                       equivalent to -vT");
    puts("  -T, --show-tabs          display TAB characters as ^I");
    puts("  -u                       (ignored)");
    puts("  -v, --show-nonprinting   use ^ and M- notation, except for LFD and TAB");
    puts("      --help               display this help and exit");
    puts("      --version            output version information and exit");
    puts("");
    puts("Examples:");
    puts("  cat f - g  Output f's contents, then standard input, then g's contents.");
    puts("  cat        Copy standard input to standard output.");
    puts("");
    puts("GNU coreutils online help: <https://www.gnu.org/software/coreutils/>");
    puts("Report any translation bugs to <https://translationproject.org/team/>");
}
 
// Function to display version information
fn show_version() -> void {
    puts("cat (Phasor coreutils) 0.1");
    puts("License GPLv3+: GNU GPL version 3 or later");
    puts("This is free software: you are free to change and redistribute it.");
    puts("There is NO WARRANTY, to the extent permitted by law.");
    puts("");
    puts("Written by Daniel McGuire");
}
 
// Process a file (or stdin if filename is "-")
fn process_file(filename: string) -> void {
    if (filename == "-") {
        var line = gets();
        while (line != null) {
            puts(line);
            line = gets();
        }
        return;
    }
    
    if (!fexists(filename)) {
        puts_error("cat: file not found");
        return;
    }
    
    var content = fread(filename);
    if (content != null) {
        puts(content);
    }
}
 
// Main function
fn main() -> int {
    var arg_count = sys_argc();
    var i = 1;
    
    if (arg_count == 1) {
        process_file("-");
        return 0;
    }
    
    // Process options
    for (; i < arg_count; i = i + 1) {
        var arg = sys_argv(i);
        
        if (arg == "--") {
            i = i + 1;
            break;
        }
        
        if (!startsWith(arg, "-")) break;
        
        if (arg == "--help") {
            show_help();
            return 0;
        }
        
        if (arg == "--version") {
            show_version();
            return 0;
        }
        
        if (arg == "-A" || arg == "--show-all") {
            g_show_all = true;
            g_show_nonprinting = true;
            g_show_ends = true;
            g_show_tabs = true;
            continue;
        }
        
        if (arg == "-b" || arg == "--number-nonblank") {
            g_number_nonblank = true;
            g_number = false;
            continue;
        }
        
        if (arg == "-e") {
            g_show_nonprinting = true;
            g_show_ends = true;
            continue;
        }
        
        if (arg == "-E" || arg == "--show-ends") {
            g_show_ends = true;
            continue;
        }
        
        if (arg == "-n" || arg == "--number") {
            if (!g_number_nonblank) g_number = true;
            continue;
        }
        
        if (arg == "-s" || arg == "--squeeze-blank") {
            g_squeeze_blank = true;
            continue;
        }
        
        if (arg == "-t") {
            g_show_nonprinting = true;
            g_show_tabs = true;
            continue;
        }
        
        if (arg == "-T" || arg == "--show-tabs") {
            g_show_tabs = true;
            continue;
        }
        
        if (arg == "-v" || arg == "--show-nonprinting") {
            g_show_nonprinting = true;
            continue;
        }
        
        puts_error("cat: invalid option");
        puts("Try 'cat --help' for more information.");
        return 1;
    }
    
    // Process files
    if (i >= arg_count) {
        process_file("-");
    } else {
        while (i < arg_count) {
            process_file(sys_argv(i));
            i = i + 1;
        }
    }
    
    return 0;
}
 
shutdown(main());