Introduce a sane interface function, from_backend(), for backends to

use when they have data from the network. Replaces the utterly daft
inbuf / inbuf_head / term_out() interface, which only made sense
when feeding to terminal.c. (terminal.c now implements
from_backend() as a small function that gateways to the old
interface.)

As a side effect, from_backend() also has an `is_stderr' parameter,
so scp can once again separate the server's pronouncements on stderr
from the actual protocol progress on stdout.

[originally from svn r729]

ldisc.c

@@ -16,8 +16,11 @@
  */
 
 static void c_write (char *buf, int len) {
-    while (len--) 
-        c_write1(*buf++);
+    from_backend(0, buf, len);
+}
+
+static void c_write1 (char c) {
+    c_write(&c, 1);
 }
 
 static char *term_buf = NULL;

plink.c

@@ -118,7 +118,7 @@ void verify_ssh_host_key(char *host, int port, char *keytype,
     }
 }
 
-HANDLE outhandle;
+HANDLE outhandle, errhandle;
 DWORD orig_console_mode;
 
 void begin_session(void) {
@@ -128,17 +128,17 @@ void begin_session(void) {
         SetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), orig_console_mode);
 }
 
-void term_out(void)
-{
-    int reap;
+void from_backend(int is_stderr, char *data, int len) {
+    int pos;
     DWORD ret;
-    reap = 0;
-    while (reap < inbuf_head) {
-        if (!WriteFile(outhandle, inbuf+reap, inbuf_head-reap, &ret, NULL))
+    HANDLE h = (is_stderr ? errhandle : outhandle);
+
+    pos = 0;
+    while (pos < len) {
+        if (!WriteFile(h, data+pos, len-pos, &ret, NULL))
             return;                    /* give up in panic */
-        reap += ret;
+        pos += ret;
     }
-    inbuf_head = 0;
 }
 
 struct input_data {
@@ -450,6 +450,7 @@ int main(int argc, char **argv) {
     GetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), &orig_console_mode);
     SetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), ENABLE_PROCESSED_INPUT);
     outhandle = GetStdHandle(STD_OUTPUT_HANDLE);
+    errhandle = GetStdHandle(STD_ERROR_HANDLE);
 
     /*
      * Now we must send the back end oodles of stuff.
@@ -504,7 +505,6 @@ int main(int argc, char **argv) {
                     break;
                 }
             }
-            term_out();
         } else if (n == 1) {
             if (idata.len > 0) {
                 back->send(idata.buffer, idata.len);

putty.h

@@ -57,8 +57,6 @@ GLOBAL int rows, cols, savelines;
 
 GLOBAL int font_width, font_height;
 
-#define c_write1(_C) do { if (inbuf_head >= INBUF_SIZE) term_out(); \
-			  inbuf[inbuf_head++] = (_C) ; } while(0)
 #define INBUF_SIZE 2048
 GLOBAL unsigned char inbuf[INBUF_SIZE];
 GLOBAL int inbuf_head;
@@ -306,6 +304,7 @@ void term_invalidate(void);
 void term_blink(int set_cursor);
 void term_paste(void);
 void term_nopaste(void);
+void from_backend(int is_stderr, char *data, int len);
 
 /*
  * Exports from raw.c.

raw.c

@@ -54,8 +54,7 @@ static void s_write (void *buf, int len) {
 }
 
 static void c_write (char *buf, int len) {
-    while (len--) 
-        c_write1(*buf++);
+    from_backend(0, buf, len);
 }
 
 /*

scp.c

@@ -246,20 +246,25 @@ void connection_fatal(char *fmt, ...)
  * is available.
  *
  * To do this, we repeatedly call the SSH protocol module, with our
- * own trap in term_out() to catch the data that comes back. We do
- * this until we have enough data.
+ * own trap in from_backend() to catch the data that comes back. We
+ * do this until we have enough data.
  */
 static unsigned char *outptr;          /* where to put the data */
 static unsigned outlen;                /* how much data required */
 static unsigned char *pending = NULL;  /* any spare data */
 static unsigned pendlen=0, pendsize=0; /* length and phys. size of buffer */
-void term_out(void) {
+void from_backend(int is_stderr, char *data, int datalen) {
+    unsigned char *p = (unsigned char *)data;
+    unsigned len = (unsigned)datalen;
+
     /*
-     * Here we must deal with a block of data, in `inbuf', size
-     * `inbuf_head'.
+     * stderr data is just spouted to local stderr and otherwise
+     * ignored.
      */
-    unsigned char *p = inbuf;
-    unsigned len = inbuf_head;
+    if (is_stderr) {
+	fwrite(data, 1, len, stderr);
+	return;
+    }
 
     inbuf_head = 0;
 
@@ -329,7 +334,6 @@ static int ssh_scp_recv(unsigned char *buf, int len) {
         if (select(1, &readfds, NULL, NULL, NULL) < 0)
             return 0;                  /* doom */
         back->msg(0, FD_READ);
-        term_out();
     }
 
     return len;
@@ -351,7 +355,6 @@ static void ssh_scp_init(void) {
         if (select(1, &readfds, NULL, NULL, NULL) < 0)
             return;                    /* doom */
         back->msg(0, FD_READ);
-        term_out();
     }
 }
 

ssh.c

@@ -322,13 +322,7 @@ static void c_write (char *buf, int len) {
                 fputc(buf[i], stderr);
 	return;
     }
-    while (len--) 
-        c_write1(*buf++);
-}
-
-static void c_writedata (char *buf, int len) {
-    while (len--)
-        c_write1(*buf++);
+    from_backend(1, buf, len);
 }
 
 /*
@@ -1674,7 +1668,8 @@ static void ssh1_protocol(unsigned char *in, int inlen, int ispkt) {
 	    if (pktin.type == SSH1_SMSG_STDOUT_DATA ||
                 pktin.type == SSH1_SMSG_STDERR_DATA) {
 		long len = GET_32BIT(pktin.body);
-		c_writedata(pktin.body+4, len);
+		from_backend(pktin.type == SSH1_SMSG_STDERR_DATA,
+			     pktin.body+4, len);
 	    } else if (pktin.type == SSH1_MSG_DISCONNECT) {
                 ssh_state = SSH_STATE_CLOSED;
 		logevent("Received disconnect request");
@@ -2414,7 +2409,8 @@ static void do_ssh2_authconn(unsigned char *in, int inlen, int ispkt)
                     continue;          /* extended but not stderr */
                 ssh2_pkt_getstring(&data, &length);
                 if (data) {
-                    c_writedata(data, length);
+                    from_backend(pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA,
+				 data, length);
                     /*
                      * Enlarge the window again at the remote side,
                      * just in case it ever runs down and they fail

telnet.c

@@ -171,6 +171,11 @@ static void s_write (void *buf, int len) {
     try_write();
 }
 
+static void c_write1(int c) {
+    char cc = (char)c;
+    from_backend(0, &cc, 1);
+}
+
 static void log_option (char *sender, int cmd, int option) {
     char buf[50];
     sprintf(buf, "%s:\t%s %s", sender,

terminal.c

@@ -2188,3 +2188,14 @@ void term_deselect (void) {
     deselect();
     term_update();
 }
+
+/*
+ * from_backend(), to get data from the backend for the terminal.
+ */
+void from_backend(int is_stderr, char *data, int len) {
+    while (len--) {
+	if (inbuf_head >= INBUF_SIZE)
+	    term_out();
+	inbuf[inbuf_head++] = *data++;
+    }
+}

window.c

@@ -1748,15 +1748,6 @@ static int check_compose(int first, int second) {
     static int recurse = 0;
     int nc = -1;
 
-    if(0)
-    {
-	char buf[256];
-	char * p;
-	sprintf(buf, "cc(%d,%d)", first, second);
-	for(p=buf; *p; p++)
-	    c_write1(*p);
-    }
-
     for(c=composetbl; *c; c++) {
 	if( (*c)[0] == first && (*c)[1] == second)
 	{
@@ -2219,7 +2210,7 @@ static int TranslateKey(UINT message, WPARAM wParam, LPARAM lParam, unsigned cha
 
 		    if ((nc=check_compose(compose_char,ch)) == -1)
 		    {
-			c_write1('\007');
+			MessageBeep(MB_ICONHAND);
 			return 0;
 		    }
 		    *p++ = xlat_kbd2tty((unsigned char)nc);