Workarounds for compiling with -D_FORTIFY_SOURCE=2 (as Ubuntu does), which

[u/mdw/putty] / unix / uxplink.c

diff --git a/unix/uxplink.c b/unix/uxplink.c
index a1dac9a..cbfcc71 100644 (file)
--- a/unix/uxplink.c
+++ b/unix/uxplink.c
@@ -107,8 +107,8 @@ char *platform_default_s(const char *name)
 {
     if (!strcmp(name, "TermType"))
        return dupstr(getenv("TERM"));
-    if (!strcmp(name, "UserName"))
-       return get_username();
+     if (!strcmp(name, "UserName"))
+       return get_username();
     if (!strcmp(name, "SerialLine"))
        return dupstr("/dev/ttyS0");
     return NULL;
@@ -384,43 +384,44 @@ void cleanup_termios(void)
 
 bufchain stdout_data, stderr_data;
 
-void try_output(int is_stderr)
+int try_output(int is_stderr)
 {
     bufchain *chain = (is_stderr ? &stderr_data : &stdout_data);
     int fd = (is_stderr ? STDERR_FILENO : STDOUT_FILENO);
     void *senddata;
-    int sendlen, ret;
+    int sendlen, ret, fl;
 
     if (bufchain_size(chain) == 0)
-        return;
-
-    bufchain_prefix(chain, &senddata, &sendlen);
-    ret = write(fd, senddata, sendlen);
-    if (ret > 0)
-       bufchain_consume(chain, ret);
-    else if (ret < 0) {
+        return bufchain_size(&stdout_data) + bufchain_size(&stderr_data);
+
+    fl = fcntl(fd, F_GETFL);
+    if (fl != -1 && !(fl & O_NONBLOCK))
+       fcntl(fd, F_SETFL, fl | O_NONBLOCK);
+    do {
+       bufchain_prefix(chain, &senddata, &sendlen);
+       ret = write(fd, senddata, sendlen);
+       if (ret > 0)
+           bufchain_consume(chain, ret);
+    } while (ret == sendlen && bufchain_size(chain) != 0);
+    if (fl != -1 && !(fl & O_NONBLOCK))
+       fcntl(fd, F_SETFL, fl);
+    if (ret < 0 && errno != EAGAIN) {
        perror(is_stderr ? "stderr: write" : "stdout: write");
        exit(1);
     }
+    return bufchain_size(&stdout_data) + bufchain_size(&stderr_data);
 }
 
 int from_backend(void *frontend_handle, int is_stderr,
                 const char *data, int len)
 {
-    int osize, esize;
-
     if (is_stderr) {
        bufchain_add(&stderr_data, data, len);
-       try_output(TRUE);
+       return try_output(TRUE);
     } else {
        bufchain_add(&stdout_data, data, len);
-       try_output(FALSE);
+       return try_output(FALSE);
     }
-
-    osize = bufchain_size(&stdout_data);
-    esize = bufchain_size(&stderr_data);
-
-    return osize + esize;
 }
 
 int from_backend_untrusted(void *frontend_handle, const char *data, int len)
@@ -512,7 +513,8 @@ int signalpipe[2];
 
 void sigwinch(int signum)
 {
-    write(signalpipe[1], "x", 1);
+    if (write(signalpipe[1], "x", 1) <= 0)
+       /* not much we can do about it */;
 }
 
 /*
@@ -868,6 +870,14 @@ int main(int argc, char **argv)
     uxsel_init();
 
     /*
+     * Unix Plink doesn't provide any way to add forwardings after the
+     * connection is set up, so if there are none now, we can safely set
+     * the "simple" flag.
+     */
+    if (cfg.protocol == PROT_SSH && !cfg.x11_forward &&        !cfg.agentfwd &&
+       cfg.portfwd[0] == '\0' && cfg.portfwd[1] == '\0')
+       cfg.ssh_simple = TRUE;
+    /*
      * Start up the connection.
      */
     logctx = log_init(NULL, &cfg);
@@ -1021,7 +1031,9 @@ int main(int argc, char **argv)
        if (FD_ISSET(signalpipe[0], &rset)) {
            char c[1];
            struct winsize size;
-           read(signalpipe[0], c, 1); /* ignore its value; it'll be `x' */
+           if (read(signalpipe[0], c, 1) <= 0)
+               /* ignore error */;
+           /* ignore its value; it'll be `x' */
            if (ioctl(0, TIOCGWINSZ, (void *)&size) >= 0)
                back->size(backhandle, size.ws_col, size.ws_row);
        }
@@ -1048,11 +1060,11 @@ int main(int argc, char **argv)
        }
 
        if (FD_ISSET(STDOUT_FILENO, &wset)) {
-           try_output(FALSE);
+           back->unthrottle(backhandle, try_output(FALSE));
        }
 
        if (FD_ISSET(STDERR_FILENO, &wset)) {
-           try_output(TRUE);
+           back->unthrottle(backhandle, try_output(TRUE));
        }
 
        if ((!connopen || !back->connected(backhandle)) &&