Add initial versionHEADmastermain

1 files changed, 119 insertions, 0 deletions

diff --git a/taketty.c b/taketty.c
new file mode 100644
index 0000000..31fb25e
--- /dev/null
+++ b/taketty.c
@@ -0,0 +1,119 @@
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <termios.h>
+#include <sys/select.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+#include <string.h>
+
+static void set_raw_mode(int fd) {
+    struct termios tios;
+
+    if (tcgetattr(fd, &tios) < 0) {
+        perror("tcgetattr");
+        exit(1);
+    }
+
+    tios.c_lflag &= ~(ICANON | ISIG | IEXTEN | ECHO);
+    tios.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
+    tios.c_cflag &= ~(CSIZE | PARENB);
+    tios.c_cflag |= CS8;
+    tios.c_oflag &= ~(OPOST);
+
+    tios.c_cc[VMIN] = 1;
+    tios.c_cc[VTIME] = 0;
+
+    if (tcsetattr(fd, TCSAFLUSH, &tios) < 0) {
+        perror("tcsetattr");
+        exit(1);
+    }
+}
+
+static void forward_io(int master_fd) {
+    fd_set rfds;
+    char buf[4096];
+    ssize_t n;
+
+    while (1) {
+        FD_ZERO(&rfds);
+        FD_SET(STDIN_FILENO, &rfds);
+        FD_SET(master_fd, &rfds);
+
+        int maxfd = (master_fd > STDIN_FILENO) ? master_fd : STDIN_FILENO;
+
+        if (select(maxfd + 1, &rfds, NULL, NULL, NULL) < 0) {
+            if (errno == EINTR) continue;
+            perror("select");
+            exit(1);
+        }
+
+        if (FD_ISSET(STDIN_FILENO, &rfds)) {
+            n = read(STDIN_FILENO, buf, sizeof(buf));
+            if (n <= 0) {
+                if (n < 0) perror("read stdin");
+                break;
+            }
+            if (write(master_fd, buf, n) != n) {
+                perror("write to master");
+                exit(1);
+            }
+        }
+
+        if (FD_ISSET(master_fd, &rfds)) {
+            n = read(master_fd, buf, sizeof(buf));
+            if (n <= 0) {
+                if (n < 0 && errno != EIO) perror("read master");
+                break;
+            }
+            if (write(STDOUT_FILENO, buf, n) != n) {
+                perror("write to stdout");
+                exit(1);
+            }
+        }
+    }
+}
+
+int main(int argc, char *argv[]) {
+    int master_fd;
+    char *slave_name;
+    struct winsize ws;
+
+    master_fd = posix_openpt(O_RDWR | O_NOCTTY);
+    if (master_fd < 0) {
+        perror("posix_openpt");
+        exit(1);
+    }
+
+    if (grantpt(master_fd) < 0) {
+        perror("grantpt");
+        exit(1);
+    }
+
+    if (unlockpt(master_fd) < 0) {
+        perror("unlockpt");
+        exit(1);
+    }
+
+    slave_name = ptsname(master_fd);
+    if (!slave_name) {
+        perror("ptsname");
+        exit(1);
+    }
+
+    if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) == 0) {
+        ioctl(master_fd, TIOCSWINSZ, &ws);
+    }
+
+    fprintf(stderr, "TAKETTY_PTY=%s\n", slave_name);
+    fflush(stderr);
+
+    set_raw_mode(STDIN_FILENO);
+
+    forward_io(master_fd);
+
+    close(master_fd);
+    return 0;
+}