Add error reporting to get_console_input_win32().

When the function setup fails due to invalid file handles, or because
WriteFile(err, ...) fails (due to file handle corruption elsewhere),
the function used to silently "return false"

Change this to print a M_WARN|M_ERRNO message.

Also, change the function style to early-return style (= large diff, but
most are indent changes only).

v2: fix spurious "}" that was left over from change to early-return.

Signed-off-by: Gert Doering <gert@greenie.muc.de>
Acked-by: Lev Stipakov <lstipakov@gmail.com>
Message-Id: <20210618181246.30769-1-gert@greenie.muc.de>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg22577.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>

diff --git a/src/openvpn/console_builtin.c b/src/openvpn/console_builtin.c
index 3214cb5fd402ebf0497345e968027e959c6b8008..9bf36347807a20e28bfd2ff6e77c0a9f08457a08 100644 (file)
--- a/src/openvpn/console_builtin.c
+++ b/src/openvpn/console_builtin.c
@@ -75,65 +75,68 @@ get_console_input_win32(const char *prompt, const bool echo, char *input, const
     in = GetStdHandle(STD_INPUT_HANDLE);
     err = get_orig_stderr();
 
-    if (in != INVALID_HANDLE_VALUE
-        && err != INVALID_HANDLE_VALUE
-        && !win32_service_interrupt(&win32_signal)
-        && WriteFile(err, prompt, strlen(prompt), &len, NULL))
+    if (in == INVALID_HANDLE_VALUE
+        || err == INVALID_HANDLE_VALUE
+        || win32_service_interrupt(&win32_signal)
+        || !WriteFile(err, prompt, strlen(prompt), &len, NULL))
     {
-        bool is_console = (GetFileType(in) == FILE_TYPE_CHAR);
-        DWORD flags_save = 0;
-        int status = 0;
-        WCHAR *winput;
+        msg(M_WARN|M_ERRNO, "get_console_input_win32(): unexpected error");
+        return false;
+    }
 
-        if (is_console)
-        {
-            if (GetConsoleMode(in, &flags_save))
-            {
-                DWORD flags = ENABLE_LINE_INPUT | ENABLE_PROCESSED_INPUT;
-                if (echo)
-                {
-                    flags |= ENABLE_ECHO_INPUT;
-                }
-                SetConsoleMode(in, flags);
-            }
-            else
-            {
-                is_console = 0;
-            }
-        }
+    bool is_console = (GetFileType(in) == FILE_TYPE_CHAR);
+    DWORD flags_save = 0;
+    int status = 0;
+    WCHAR *winput;
 
-        if (is_console)
+    if (is_console)
+    {
+        if (GetConsoleMode(in, &flags_save))
         {
-            winput = malloc(capacity * sizeof(WCHAR));
-            if (winput == NULL)
+            DWORD flags = ENABLE_LINE_INPUT | ENABLE_PROCESSED_INPUT;
+            if (echo)
             {
-                return false;
+                flags |= ENABLE_ECHO_INPUT;
             }
-
-            status = ReadConsoleW(in, winput, capacity, &len, NULL);
-            WideCharToMultiByte(CP_UTF8, 0, winput, len, input, capacity, NULL, NULL);
-            free(winput);
+            SetConsoleMode(in, flags);
         }
         else
         {
-            status = ReadFile(in, input, capacity, &len, NULL);
+            is_console = 0;
         }
+    }
 
-        string_null_terminate(input, (int)len, capacity);
-        chomp(input);
-
-        if (!echo)
-        {
-            WriteFile(err, "\r\n", 2, &len, NULL);
-        }
-        if (is_console)
-        {
-            SetConsoleMode(in, flags_save);
-        }
-        if (status && !win32_service_interrupt(&win32_signal))
+    if (is_console)
+    {
+        winput = malloc(capacity * sizeof(WCHAR));
+        if (winput == NULL)
         {
-            return true;
+            return false;
         }
+
+        status = ReadConsoleW(in, winput, capacity, &len, NULL);
+        WideCharToMultiByte(CP_UTF8, 0, winput, len, input, capacity, NULL, NULL);
+        free(winput);
+    }
+    else
+    {
+        status = ReadFile(in, input, capacity, &len, NULL);
+    }
+
+    string_null_terminate(input, (int)len, capacity);
+    chomp(input);
+
+    if (!echo)
+    {
+        WriteFile(err, "\r\n", 2, &len, NULL);
+    }
+    if (is_console)
+    {
+        SetConsoleMode(in, flags_save);
+    }
+    if (status && !win32_service_interrupt(&win32_signal))
+    {
+        return true;
     }
 
     return false;