merge(third_party/git): Merge squashed git subtree at v2.23.0

Merge commit '1b593e1ea4' as 'third_party/git'

third_party/git/compat/terminal.c

@@ -0,0 +1,147 @@
+#include "git-compat-util.h"
+#include "compat/terminal.h"
+#include "sigchain.h"
+#include "strbuf.h"
+
+#if defined(HAVE_DEV_TTY) || defined(GIT_WINDOWS_NATIVE)
+
+static void restore_term(void);
+
+static void restore_term_on_signal(int sig)
+{
+	restore_term();
+	sigchain_pop(sig);
+	raise(sig);
+}
+
+#ifdef HAVE_DEV_TTY
+
+#define INPUT_PATH "/dev/tty"
+#define OUTPUT_PATH "/dev/tty"
+
+static int term_fd = -1;
+static struct termios old_term;
+
+static void restore_term(void)
+{
+	if (term_fd < 0)
+		return;
+
+	tcsetattr(term_fd, TCSAFLUSH, &old_term);
+	close(term_fd);
+	term_fd = -1;
+}
+
+static int disable_echo(void)
+{
+	struct termios t;
+
+	term_fd = open("/dev/tty", O_RDWR);
+	if (tcgetattr(term_fd, &t) < 0)
+		goto error;
+
+	old_term = t;
+	sigchain_push_common(restore_term_on_signal);
+
+	t.c_lflag &= ~ECHO;
+	if (!tcsetattr(term_fd, TCSAFLUSH, &t))
+		return 0;
+
+error:
+	close(term_fd);
+	term_fd = -1;
+	return -1;
+}
+
+#elif defined(GIT_WINDOWS_NATIVE)
+
+#define INPUT_PATH "CONIN$"
+#define OUTPUT_PATH "CONOUT$"
+#define FORCE_TEXT "t"
+
+static HANDLE hconin = INVALID_HANDLE_VALUE;
+static DWORD cmode;
+
+static void restore_term(void)
+{
+	if (hconin == INVALID_HANDLE_VALUE)
+		return;
+
+	SetConsoleMode(hconin, cmode);
+	CloseHandle(hconin);
+	hconin = INVALID_HANDLE_VALUE;
+}
+
+static int disable_echo(void)
+{
+	hconin = CreateFile("CONIN$", GENERIC_READ | GENERIC_WRITE,
+	    FILE_SHARE_READ, NULL, OPEN_EXISTING,
+	    FILE_ATTRIBUTE_NORMAL, NULL);
+	if (hconin == INVALID_HANDLE_VALUE)
+		return -1;
+
+	GetConsoleMode(hconin, &cmode);
+	sigchain_push_common(restore_term_on_signal);
+	if (!SetConsoleMode(hconin, cmode & (~ENABLE_ECHO_INPUT))) {
+		CloseHandle(hconin);
+		hconin = INVALID_HANDLE_VALUE;
+		return -1;
+	}
+
+	return 0;
+}
+
+#endif
+
+#ifndef FORCE_TEXT
+#define FORCE_TEXT
+#endif
+
+char *git_terminal_prompt(const char *prompt, int echo)
+{
+	static struct strbuf buf = STRBUF_INIT;
+	int r;
+	FILE *input_fh, *output_fh;
+
+	input_fh = fopen(INPUT_PATH, "r" FORCE_TEXT);
+	if (!input_fh)
+		return NULL;
+
+	output_fh = fopen(OUTPUT_PATH, "w" FORCE_TEXT);
+	if (!output_fh) {
+		fclose(input_fh);
+		return NULL;
+	}
+
+	if (!echo && disable_echo()) {
+		fclose(input_fh);
+		fclose(output_fh);
+		return NULL;
+	}
+
+	fputs(prompt, output_fh);
+	fflush(output_fh);
+
+	r = strbuf_getline_lf(&buf, input_fh);
+	if (!echo) {
+		putc('\n', output_fh);
+		fflush(output_fh);
+	}
+
+	restore_term();
+	fclose(input_fh);
+	fclose(output_fh);
+
+	if (r == EOF)
+		return NULL;
+	return buf.buf;
+}
+
+#else
+
+char *git_terminal_prompt(const char *prompt, int echo)
+{
+	return getpass(prompt);
+}
+
+#endif