diff options
| -rw-r--r-- | libbutl/fdstream.cxx | 55 | ||||
| -rw-r--r-- | libbutl/fdstream.hxx | 8 |
2 files changed, 61 insertions, 2 deletions
diff --git a/libbutl/fdstream.cxx b/libbutl/fdstream.cxx index 8098e50..07cb9f2 100644 --- a/libbutl/fdstream.cxx +++ b/libbutl/fdstream.cxx @@ -17,6 +17,10 @@ #else # include <libbutl/win32-utility.hxx> +# ifndef ENABLE_VIRTUAL_TERMINAL_PROCESSING +# define ENABLE_VIRTUAL_TERMINAL_PROCESSING 0x04 +# endif + # include <io.h> // _close(), _read(), _write(), _setmode(), _sopen(), // _lseek(), _dup(), _pipe(), _chsize_s, // _get_osfhandle() @@ -42,7 +46,8 @@ #include <new> // bad_alloc #include <limits> // numeric_limits #include <cassert> -#include <cstring> // memcpy(), memmove(), memchr() +#include <cstring> // memcpy(), memmove(), memchr(), strcmp() +#include <cstdlib> // getenv() #include <iostream> // cin, cout #include <exception> // uncaught_exception[s]() #include <stdexcept> // invalid_argument @@ -1439,6 +1444,16 @@ namespace butl throw_generic_ios_failure (errno); } + bool + fdterm_color (int, bool) + { + const char* t (std::getenv ("TERM")); + + // This test was lifted from GCC (Emacs shell sets TERM=dumb). + // + return t != nullptr && strcmp (t, "dumb") != 0; + } + static pair<size_t, size_t> fdselect (fdselect_set& read, fdselect_set& write, @@ -1859,7 +1874,7 @@ namespace butl fdterm (int fd) { // @@ Both GCC and Clang simply call GetConsoleMode() for this check. I - // wonder why we don't do the same? + // wonder why we don't do the same? See also fdterm_color() below. // We don't need to close it (see fd_to_handle()). // @@ -1946,6 +1961,42 @@ namespace butl return false; } + bool + fdterm_color (int fd, bool enable) + { + // We don't need to close it (see fd_to_handle()). + // + HANDLE h (fd_to_handle (fd)); + + // See GH issue #312 for background on this logic. + // + DWORD m; + if (!GetConsoleMode (h, &m)) + throw_system_ios_failure (GetLastError ()); + + // Some terminals (e.g. Windows Terminal) enable VT processing by default. + // + if ((m & ENABLE_VIRTUAL_TERMINAL_PROCESSING) != 0) + return true; + + if (enable) + { + // If SetConsoleMode() fails, assume VT processing is unsupported (it + // is only supported from a certain build of Windows 10). + // + // Note that Wine pretends to support this but doesn't handle the escape + // sequences. See https://bugs.winehq.org/show_bug.cgi?id=49780. + // + if (SetConsoleMode (h, + (m | + ENABLE_PROCESSED_OUTPUT | + ENABLE_VIRTUAL_TERMINAL_PROCESSING))) + return true; + } + + return false; + } + static pair<size_t, size_t> fdselect (fdselect_set& read, fdselect_set& write, diff --git a/libbutl/fdstream.hxx b/libbutl/fdstream.hxx index 683a2f2..9c8f786 100644 --- a/libbutl/fdstream.hxx +++ b/libbutl/fdstream.hxx @@ -901,6 +901,14 @@ namespace butl LIBBUTL_SYMEXPORT bool fdterm (int); + // Test whether a terminal file descriptor supports ANSI color output. If + // the enable argument is true, then also try to enable color output (only + // applicable on some platforms, such as Windows). Throw ios::failure on the + // underlying OS error. + // + LIBBUTL_SYMEXPORT bool + fdterm_color (int, bool enable); + // Wait until one or more file descriptors becomes ready for input (reading) // or output (writing). Return the pair of numbers of descriptors that are // ready. Throw std::invalid_argument if anything is wrong with arguments |