ndk-patches: implement getpass()

6 years ago · 5a8b31b3a6
1 changed files with 77 additions and 0 deletions
--- a/ndk-patches/unistd.h.patch
+++ b/ndk-patches/unistd.h.patch
@ -0,0 +1,77 @@
+--- sysroot/usr/include/unistd.h	2018-04-30 19:24:22.000000000 +0000
+++ usr/include/unistd.h	2018-08-16 10:42:51.158596753 +0000
+@@ -302,6 +302,74 @@
+ #include <bits/fortify/unistd.h>
+ #endif
+ 
+#if !defined GETPASS_H && !defined getpass && !defined HAVE_GETPASS && !defined HAS_GETPASS && !defined NO_INLINE_GETPASS
+#define GETPASS_H 1
+#define HAVE_GETPASS 1
+#define HAS_GETPASS 1
+#define PASSWORDLEN 512
+
+static __inline__ char* getpass(const char* prompt) {
+    // termios struct as in asm-generic/termbits.h
+    struct _termios {
+        unsigned int c_iflag;              /* input mode flags */
+        unsigned int c_oflag;              /* output mode flags */
+        unsigned int c_cflag;              /* control mode flags */
+        unsigned int c_lflag;              /* local mode flags */
+        unsigned char c_line;              /* line discipline */
+        unsigned char c_cc[19/* NCCS */];  /* control characters */
+    };
+
+    struct _termios term_old, term_new;
+    static char password[513] = { 0 }; /* 512 1-byte charactes and '0' */
+    int len = 0, tty_changed = 0;
+
+    // print prompt
+    while (*prompt) {
+        write(1, prompt, 1);
+        prompt++;
+    }
+
+    // try to disable echoing on terminal
+    if (ioctl(0, 0x5401 /* TCGETS */, &term_old) == 0) {
+        term_new = term_old;
+        term_new.c_lflag &= ~0000010;/* ~ECHO */
+
+        if (ioctl(0, 0x5402+0 /* TCSETS+TCSANOW */, &term_new) == 0) {
+            tty_changed = 1;
+        } else {
+            tty_changed = 0;
+        }
+    }
+
+    // read password
+    char chr;
+    while (read(0, &chr, sizeof(char)) > 0) {
+        if (chr == '\r' || chr == '\n' || chr == 0) {
+            break;
+        }
+
+        if (len == sizeof(password)-1) {
+            // we should consume all entered characters even
+            // if maximal input length reached
+            continue;
+        } else {
+            password[len++] = chr;
+        }
+    }
+    password[len] = 0;
+
+    // restore terminal to previous state if needed
+    if (tty_changed) {
+        ioctl(0, 0x5402+0 /* TCSETS+TCSANOW */, &term_old);
+    }
+
+    // force new line
+    write(1, "\n", 1);
+
+    return password;
+}
+#endif
+
+ __END_DECLS
+ 
+ #endif