dart-sdk/runtime/bin/stdio_macos.cc
Wesley Moy 4e047f2931 Add common terminals to ANSI heuristic
Today, Stdout and Stderr have a property supportsAnsiEscapes. The
documented purpose of this property is to inform the caller whether ANSI
escape sequences are supported - say, for colorizing terminal output
when the user is running the Dart program in a terminal emulator like
xterm.

The problem is that the heuristic used is a substring match for "xterm"
in the TERM environment variable. (See attached bug.) This
implementation omits a few significant populations of users:

* Users using screen or tmux. These commands set their TERM to "screen".
* Users using a non-xterm terminal like rxvt (especially rxvt-unicode).

The correct solution here is to query terminfo for terminal
capabilities. Until then, adding these two cases to the existing xterm
check unblocks users of two popular terminal multiplexers and a terminal
emulator.

Bug: https://github.com/dart-lang/sdk/issues/31606
Change-Id: I1a8a37d42f1895d7b1238c67ec86207fd4a38bbb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149940
Auto-Submit: Wesley Moy <wesleymoy@google.com>
Reviewed-by: Jonas Termansen <sortie@google.com>
Reviewed-by: Zichang Guo <zichangguo@google.com>
Commit-Queue: Jonas Termansen <sortie@google.com>
2020-06-09 21:33:35 +00:00

115 lines
2.7 KiB
C++

// Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "platform/globals.h"
#if defined(HOST_OS_MACOS)
#include "bin/stdio.h"
#include <errno.h> // NOLINT
#include <sys/ioctl.h> // NOLINT
#include <termios.h> // NOLINT
#include "bin/fdutils.h"
#include "platform/signal_blocker.h"
namespace dart {
namespace bin {
bool Stdin::ReadByte(intptr_t fd, int* byte) {
unsigned char b;
ssize_t s = TEMP_FAILURE_RETRY(read(fd, &b, 1));
if (s < 0) {
return false;
}
*byte = (s == 0) ? -1 : b;
return true;
}
bool Stdin::GetEchoMode(intptr_t fd, bool* enabled) {
struct termios term;
int status = NO_RETRY_EXPECTED(tcgetattr(fd, &term));
if (status != 0) {
return false;
}
*enabled = ((term.c_lflag & ECHO) != 0);
return true;
}
bool Stdin::SetEchoMode(intptr_t fd, bool enabled) {
struct termios term;
int status = NO_RETRY_EXPECTED(tcgetattr(fd, &term));
if (status != 0) {
return false;
}
if (enabled) {
term.c_lflag |= (ECHO | ECHONL);
} else {
term.c_lflag &= ~(ECHO | ECHONL);
}
status = NO_RETRY_EXPECTED(tcsetattr(fd, TCSANOW, &term));
return (status == 0);
}
bool Stdin::GetLineMode(intptr_t fd, bool* enabled) {
struct termios term;
int status = NO_RETRY_EXPECTED(tcgetattr(fd, &term));
if (status != 0) {
return false;
}
*enabled = ((term.c_lflag & ICANON) != 0);
return true;
}
bool Stdin::SetLineMode(intptr_t fd, bool enabled) {
struct termios term;
int status = NO_RETRY_EXPECTED(tcgetattr(fd, &term));
if (status != 0) {
return false;
}
if (enabled) {
term.c_lflag |= ICANON;
} else {
term.c_lflag &= ~(ICANON);
}
status = NO_RETRY_EXPECTED(tcsetattr(fd, TCSANOW, &term));
return (status == 0);
}
static bool TermIsKnownToSupportAnsi() {
const char* term = getenv("TERM");
if (term == NULL) {
return false;
}
return strstr(term, "xterm") != NULL || strstr(term, "screen") != NULL ||
strstr(term, "rxvt") != NULL;
}
bool Stdin::AnsiSupported(intptr_t fd, bool* supported) {
*supported = isatty(fd) && TermIsKnownToSupportAnsi();
return true;
}
bool Stdout::GetTerminalSize(intptr_t fd, int size[2]) {
struct winsize w;
int status = NO_RETRY_EXPECTED(ioctl(fd, TIOCGWINSZ, &w));
if ((status == 0) && ((w.ws_col != 0) || (w.ws_row != 0))) {
size[0] = w.ws_col;
size[1] = w.ws_row;
return true;
}
return false;
}
bool Stdout::AnsiSupported(intptr_t fd, bool* supported) {
*supported = isatty(fd) && TermIsKnownToSupportAnsi();
return true;
}
} // namespace bin
} // namespace dart
#endif // defined(HOST_OS_MACOS)