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const std = @import("std");
const parser = @import("parser.zig");
const shell = @import("shell.zig");
const builtins = @import("builtins.zig");
const BUILTINS = [_][]const u8{ "echo", "exit" };
fn tryComplete(allocator: std.mem.Allocator, partial: []const u8) ?[]const u8 {
var matches: usize = 0;
var match: ?[]const u8 = null;
var match_is_builtin = false;
for (BUILTINS) |builtin| {
if (std.mem.startsWith(u8, builtin, partial)) {
matches += 1;
if (matches == 1) {
match = builtin;
match_is_builtin = true;
}
if (matches > 1) {
if (match != null and !match_is_builtin) {
allocator.free(match.?);
}
return null;
}
}
}
const path_env = std.posix.getenv("PATH") orelse {
if (matches == 1 and match != null) {
return allocator.dupe(u8, match.?) catch null;
}
return null;
};
var path_iter = std.mem.splitScalar(u8, path_env, ':');
while (path_iter.next()) |dir_path| {
if (dir_path.len == 0) continue;
var dir = std.fs.openDirAbsolute(dir_path, .{ .iterate = true }) catch continue;
defer dir.close();
var iter = dir.iterate();
while (iter.next() catch continue) |entry| {
if (entry.kind == .file or entry.kind == .sym_link) {
if (std.mem.startsWith(u8, entry.name, partial)) {
const stat = dir.statFile(entry.name) catch continue;
if (stat.mode & 0o111 != 0) {
if (match != null and match_is_builtin and std.mem.eql(u8, match.?, entry.name)) {
continue;
}
matches += 1;
if (matches == 1) {
match = allocator.dupe(u8, entry.name) catch continue;
match_is_builtin = false;
} else {
if (match != null and !match_is_builtin) {
allocator.free(match.?);
}
return null;
}
}
}
}
}
}
if (matches == 1 and match != null) {
if (match_is_builtin) {
return allocator.dupe(u8, match.?) catch null;
} else {
return match.?;
}
}
return null;
}
fn enableRawMode(fd: std.posix.fd_t) !std.posix.termios {
const original = try std.posix.tcgetattr(fd);
var raw = original;
raw.lflag.ICANON = false;
raw.lflag.ECHO = false;
raw.cc[@intFromEnum(std.posix.V.MIN)] = 1;
raw.cc[@intFromEnum(std.posix.V.TIME)] = 0;
try std.posix.tcsetattr(fd, .FLUSH, raw);
return original;
}
fn disableRawMode(fd: std.posix.fd_t, original: std.posix.termios) !void {
try std.posix.tcsetattr(fd, .FLUSH, original);
}
fn readCommand(allocator: std.mem.Allocator) !?[]const u8 {
const stdin = std.fs.File.stdin();
const stdout = std.fs.File.stdout();
const stdin_fd = stdin.handle;
const is_tty = std.posix.isatty(stdin_fd);
const original_termios = if (is_tty) try enableRawMode(stdin_fd) else null;
defer if (original_termios) |orig| disableRawMode(stdin_fd, orig) catch {};
var buffer = std.ArrayList(u8){};
defer buffer.deinit(allocator);
var byte: [1]u8 = undefined;
while (true) {
const bytes_read = try stdin.read(&byte);
if (bytes_read == 0) return null;
const c = byte[0];
if (c == '\n' or c == '\r') {
return try buffer.toOwnedSlice(allocator);
} else if (c == '\t' and is_tty) {
const partial = buffer.items;
if (partial.len > 0 and std.mem.indexOf(u8, partial, " ") == null) {
if (tryComplete(allocator, partial)) |completion| {
defer allocator.free(completion);
const remaining = completion[partial.len..];
try stdout.writeAll(remaining);
try stdout.writeAll(" ");
try buffer.appendSlice(allocator, remaining);
try buffer.append(allocator, ' ');
} else {
try stdout.writeAll("\x07");
}
}
} else if ((c == 127 or c == 8) and is_tty) {
if (buffer.items.len > 0) {
_ = buffer.pop();
try stdout.writeAll("\x08 \x08");
}
} else if (c >= 32 and c < 127) {
try buffer.append(allocator, c);
if (is_tty) {
try stdout.writeAll(&[_]u8{c});
}
} else if (c == '\t' and !is_tty) {
try buffer.append(allocator, c);
}
}
}
pub fn main() !void {
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
defer _ = gpa.deinit();
const allocator = gpa.allocator();
const stdout = std.fs.File.stdout();
while (true) {
try stdout.writeAll("$ ");
const command = try readCommand(allocator);
if (command) |cmd| {
defer allocator.free(cmd);
try stdout.writeAll("\n");
const parsed = parser.parseCommand(cmd);
var stdout_writer = std.fs.File.stdout().writerStreaming(&.{});
const stdout_iface = &stdout_writer.interface;
const result = try shell.executeCommand(allocator, stdout_iface, parsed.name, parsed.args, parsed.output_redirect, parsed.error_redirect, parsed.append_output, parsed.append_error);
if (result == .exit_shell) break;
} else {
break;
}
}
}
|
