ash: Expand here-documents in the current shell environment

[oweals/busybox.git] / libbb / bb_askpass.c

diff --git a/libbb/bb_askpass.c b/libbb/bb_askpass.c
index f9b918cecef643a070d35a33d6d7aec88f25524d..2dcead35ab2149d47de280f562259f81edf67f4e 100644 (file)
--- a/libbb/bb_askpass.c
+++ b/libbb/bb_askpass.c
@@ -1,13 +1,11 @@
 /* vi: set sw=4 ts=4: */
 /*
  * Ask for a password
- * I use a static buffer in this function.  Plan accordingly.
  *
  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
-
 #include "libbb.h"
 
 /* do nothing signal handler */
@@ -15,38 +13,40 @@ static void askpass_timeout(int UNUSED_PARAM ignore)
 {
 }
 
-char* FAST_FUNC bb_ask_stdin(const char *prompt)
-{
-       return bb_ask(STDIN_FILENO, 0, prompt);
-}
-char* FAST_FUNC bb_ask(const int fd, int timeout, const char *prompt)
+char* FAST_FUNC bb_ask_noecho(int fd, int timeout, const char *prompt)
 {
-       /* Was static char[BIGNUM] */
-       enum { sizeof_passwd = 128 };
-       static char *passwd;
-
+#define MAX_LINE 0xfff
        char *ret;
        int i;
        struct sigaction sa, oldsa;
        struct termios tio, oldtio;
 
-       if (!passwd)
-               passwd = xmalloc(sizeof_passwd);
-       memset(passwd, 0, sizeof_passwd);
+       tcflush(fd, TCIFLUSH);
+       /* Was buggy: was printing prompt *before* flushing input,
+        * which was upsetting "expect" based scripts of some users.
+        */
+       fputs(prompt, stdout);
+       fflush_all();
 
        tcgetattr(fd, &oldtio);
-       tcflush(fd, TCIFLUSH);
        tio = oldtio;
-#ifndef IUCLC
-# define IUCLC 0
-#endif
-       tio.c_iflag &= ~(IUCLC|IXON|IXOFF|IXANY);
-       tio.c_lflag &= ~(ECHO|ECHOE|ECHOK|ECHONL|TOSTOP);
-       tcsetattr_stdin_TCSANOW(&tio);
+       /* Switch off echo. ECHOxyz meaning:
+        * ECHO    echo input chars
+        * ECHOE   echo BS-SP-BS on erase character
+        * ECHOK   echo kill char specially, not as ^c (ECHOKE controls how exactly)
+        * ECHOKE  erase all input via BS-SP-BS on kill char (else go to next line)
+        * ECHOCTL Echo ctrl chars as ^c (else echo verbatim:
+        *         e.g. up arrow emits "ESC-something" and thus moves cursor up!)
+        * ECHONL  Echo NL even if ECHO is not set
+        * ECHOPRT On erase, echo erased chars
+        *         [qwe<BS><BS><BS> input looks like "qwe\ewq/" on screen]
+        */
+       tio.c_lflag &= ~(ECHO|ECHOE|ECHOK|ECHONL);
+       tcsetattr(fd, TCSANOW, &tio);
 
        memset(&sa, 0, sizeof(sa));
        /* sa.sa_flags = 0; - no SA_RESTART! */
-       /* SIGINT and SIGALRM will interrupt read below */
+       /* SIGINT and SIGALRM will interrupt reads below */
        sa.sa_handler = askpass_timeout;
        sigaction(SIGINT, &sa, &oldsa);
        if (timeout) {
@@ -54,29 +54,46 @@ char* FAST_FUNC bb_ask(const int fd, int timeout, const char *prompt)
                alarm(timeout);
        }
 
-       fputs(prompt, stdout);
-       fflush_all();
        ret = NULL;
-       /* On timeout or Ctrl-C, read will hopefully be interrupted,
-        * and we return NULL */
-       if (read(fd, passwd, sizeof_passwd - 1) > 0) {
-               ret = passwd;
-               i = 0;
-               /* Last byte is guaranteed to be 0
-                  (read did not overwrite it) */
-               do {
-                       if (passwd[i] == '\r' || passwd[i] == '\n')
-                               passwd[i] = '\0';
-               } while (passwd[i++]);
+       i = 0;
+       while (1) {
+               int r;
+
+               /* User input is uber-slow, no need to optimize reallocs.
+                * Grow it on every char.
+                */
+               ret = xrealloc(ret, i + 2);
+               r = read(fd, &ret[i], 1);
+
+               if ((i == 0 && r == 0) /* EOF (^D) with no password */
+                || r < 0 /* read is interrupted by timeout or ^C */
+               ) {
+                       ret[i] = '\0'; /* paranoia */
+                       nuke_str(ret); /* paranoia */
+                       free(ret);
+                       ret = NULL;
+                       break;
+               }
+
+               if (r == 0 /* EOF */
+                || ret[i] == '\r' || ret[i] == '\n' /* EOL */
+                || ++i == MAX_LINE /* line limit */
+               ) {
+                       ret[i] = '\0';
+                       break;
+               }
        }
 
        if (timeout) {
                alarm(0);
        }
        sigaction_set(SIGINT, &oldsa);
-
-       tcsetattr_stdin_TCSANOW(&oldtio);
+       tcsetattr(fd, TCSANOW, &oldtio);
        bb_putchar('\n');
        fflush_all();
        return ret;
 }
+char* FAST_FUNC bb_ask_noecho_stdin(const char *prompt)
+{
+       return bb_ask_noecho(STDIN_FILENO, 0, prompt);
+}