vtysh: use poll/callback-driven readline interface

Create a thread_master and funnel readline terminal I/O through it.
This allows processing other input in parallel, e.g. log messages.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

diff --git a/vtysh/vtysh.h b/vtysh/vtysh.h
index 757b832a90d7fbb6866e26d345b78fe022a2bc5b..8fb85293e559ac8aee5d094a326e83cf52b71fac 100644 (file)
--- a/vtysh/vtysh.h
+++ b/vtysh/vtysh.h
@@ -73,6 +73,7 @@ extern enum vtysh_write_integrated vtysh_write_integrated;
 
 extern char frr_config[];
 extern char vtydir[];
+extern bool vtysh_loop_exited;
 
 void vtysh_init_vty(void);
 void vtysh_uninit(void);

diff --git a/vtysh/vtysh_main.c b/vtysh/vtysh_main.c
index a4f27b61cb3fafa31bcd8e9c78456d9c69012ebe..04eb47feeb8a5529ed658a3d65c8bb3080f4fd9c 100644 (file)
--- a/vtysh/vtysh_main.c
+++ b/vtysh/vtysh_main.c
@@ -84,9 +84,6 @@ static sigjmp_buf jmpbuf;
 /* Flag for avoid recursive siglongjmp() call. */
 static int jmpflag = 0;
 
-/* A static variable for holding the line. */
-static char *line_read;
-
 /* Master of threads. */
 struct thread_master *master;
 
@@ -208,23 +205,22 @@ struct option longopts[] = {
        {"timestamp", no_argument, NULL, 't'},
        {0}};
 
-/* Read a string, and return a pointer to it.  Returns NULL on EOF. */
-static char *vtysh_rl_gets(void)
+bool vtysh_loop_exited;
+
+static void vtysh_rl_callback(char *line_read)
 {
        HIST_ENTRY *last;
-       /* If the buffer has already been allocated, return the memory
-        * to the free pool. */
-       if (line_read) {
-               free(line_read);
-               line_read = NULL;
-       }
 
-       /* Get a line from the user.  Change prompt according to node.  XXX. */
-       line_read = readline(vtysh_prompt());
+       rl_callback_handler_remove();
+
+       if (!line_read) {
+               vtysh_loop_exited = true;
+               return;
+       }
 
        /* If the line has any text in it, save it on the history. But only if
         * last command in history isn't the same one. */
-       if (line_read && *line_read) {
+       if (*line_read) {
                using_history();
                last = previous_history();
                if (!last || strcmp(last->line, line_read) != 0) {
@@ -233,7 +229,39 @@ static char *vtysh_rl_gets(void)
                }
        }
 
-       return (line_read);
+       vtysh_execute(line_read);
+
+       if (!vtysh_loop_exited)
+               rl_callback_handler_install(vtysh_prompt(), vtysh_rl_callback);
+}
+
+static struct thread *vtysh_rl_read_thread;
+
+static void vtysh_rl_read(struct thread *thread)
+{
+       thread_add_read(master, vtysh_rl_read, NULL, STDIN_FILENO,
+                       &vtysh_rl_read_thread);
+       rl_callback_read_char();
+}
+
+/* Read a string, and return a pointer to it.  Returns NULL on EOF. */
+static void vtysh_rl_run(void)
+{
+       struct thread thread;
+
+       master = thread_master_create(NULL);
+
+       rl_callback_handler_install(vtysh_prompt(), vtysh_rl_callback);
+       thread_add_read(master, vtysh_rl_read, NULL, STDIN_FILENO,
+                       &vtysh_rl_read_thread);
+
+       while (!vtysh_loop_exited && thread_fetch(master, &thread))
+               thread_call(&thread);
+
+       if (!vtysh_loop_exited)
+               rl_callback_handler_remove();
+
+       thread_master_free(master);
 }
 
 static void log_it(const char *line)
@@ -458,7 +486,6 @@ int main(int argc, char **argv, char **env)
        }
 
        /* Initialize user input buffer. */
-       line_read = NULL;
        setlinebuf(stdout);
 
        /* Signal and others. */
@@ -730,8 +757,7 @@ int main(int argc, char **argv, char **env)
        jmpflag = 1;
 
        /* Main command loop. */
-       while (vtysh_rl_gets())
-               vtysh_execute(line_read);
+       vtysh_rl_run();
 
        vtysh_uninit();