sysdb: Use the asynchronous readline interface; handle asynch server replies.

[sysdb.git] / src / tools / sysdb / input.c

diff --git a/src/tools/sysdb/input.c b/src/tools/sysdb/input.c
index e08ad5b40da52d63ce9b16ebda9e0916193b6db0..c42390f2d1fafd29801523449bbaa1a0c7192e7e 100644 (file)
--- a/src/tools/sysdb/input.c
+++ b/src/tools/sysdb/input.c
@@ -34,11 +34,16 @@
 
 #include "utils/strbuf.h"
 
+#include <sys/select.h>
+
 #include <stdio.h>
 #include <stdlib.h>
 
 #include <string.h>
 
+#include <termios.h>
+#include <unistd.h>
+
 #if HAVE_EDITLINE_READLINE_H
 #      include <editline/readline.h>
 #      if HAVE_EDITLINE_HISTORY_H
@@ -62,32 +67,109 @@
 
 sdb_input_t *sysdb_input = NULL;
 
+/*
+ * private variables
+ */
+
+static struct termios orig_term_attrs;
+
 /*
  * private helper functions
  */
 
-static size_t
-input_readline(void)
+static void
+reset_term_attrs(void)
 {
-       const char *prompt = "sysdb=> ";
-       char *line;
+       tcsetattr(STDIN_FILENO, TCSANOW, &orig_term_attrs);
+} /* reset_term_attrs */
+
+static void
+term_rawmode(void)
+{
+       struct termios attrs;
+
+       /* setup terminal to operate in non-canonical mode
+        * and single character input */
+       memset(&orig_term_attrs, 0, sizeof(orig_term_attrs));
+       tcgetattr(STDIN_FILENO, &orig_term_attrs);
+       atexit(reset_term_attrs);
+
+       memset(&attrs, 0, sizeof(attrs));
+       tcgetattr(STDIN_FILENO, &attrs);
+       attrs.c_lflag &= (tcflag_t)(~ICANON);
+       attrs.c_cc[VMIN] = 1;
+       tcsetattr(STDIN_FILENO, TCSANOW, &attrs);
+} /* term_rawmode */
+
+static void
+handle_input(char *line)
+{
+       if (! line) {
+               sysdb_input->eof = 1;
+               return;
+       }
 
+       sdb_strbuf_append(sysdb_input->input, line);
+       sdb_strbuf_append(sysdb_input->input, "\n");
+       free(line);
+
+       rl_callback_handler_remove();
+} /* handle_input */
+
+/* wait for a new line of data to be available */
+static ssize_t
+input_readline(void)
+{
        size_t len;
 
+       fd_set fds;
+       int client_fd;
+
+       const char *prompt = "sysdb=> ";
+
        if (sysdb_input->query_len)
                prompt = "sysdb-> ";
 
-       line = readline(prompt);
+       rl_callback_handler_install(prompt, handle_input);
+       client_fd = sdb_client_sockfd(sysdb_input->client);
 
-       if (! line)
-               return 0;
+       len = sdb_strbuf_len(sysdb_input->input);
+       while ((sdb_strbuf_len(sysdb_input->input) == len)
+                       && (! sysdb_input->eof)) {
+               int n;
 
-       len = strlen(line) + 1;
+               /* XXX: some versions of libedit don't properly reset the terminal in
+                * rl_callback_read_char(); detect those versions */
+               term_rawmode();
 
-       sdb_strbuf_append(sysdb_input->input, line);
-       sdb_strbuf_append(sysdb_input->input, "\n");
-       free(line);
-       return len;
+               FD_ZERO(&fds);
+               FD_SET(STDIN_FILENO, &fds);
+               FD_SET(client_fd, &fds);
+
+               n = select(client_fd + 1, &fds, NULL, NULL, /* timeout = */ NULL);
+               if (n < 0)
+                       return (ssize_t)n;
+               else if (! n)
+                       continue;
+
+               /* handle user input with highest priority */
+               if (FD_ISSET(STDIN_FILENO, &fds)) {
+                       rl_callback_read_char();
+                       continue;
+               }
+
+               if (! FD_ISSET(client_fd, &fds))
+                       continue;
+
+               /* some response / error message from the server pending */
+               /* XXX: clear current line */
+               printf("\n");
+               sdb_command_print_reply(sysdb_input);
+               rl_forced_update_display();
+       }
+
+       /* new data available */
+       return (ssize_t)(sdb_strbuf_len(sysdb_input->input) - len);
 } /* input_readline */
 
 /*
@@ -99,6 +181,11 @@ sdb_input_init(sdb_input_t *input)
 {
        /* register input handler */
        sysdb_input = input;
+
+       if (! isatty(STDIN_FILENO))
+               return -1;
+
+       term_rawmode();
        return 0;
 } /* sdb_input_init */
 
@@ -111,12 +198,12 @@ sdb_input_readline(char *buf, int *n_chars, size_t max_chars)
        len = sdb_strbuf_len(sysdb_input->input) - sysdb_input->tokenizer_pos;
 
        if (! len) {
-               size_t n = input_readline();
-               if (! n) {
+               ssize_t n = input_readline();
+               if (n <= 0) {
                        *n_chars = 0; /* YY_NULL */
-                       return 0;
+                       return n;
                }
-               len += n;
+               len += (size_t)n;
        }
 
        len = (len < max_chars) ? len : max_chars;
@@ -130,7 +217,7 @@ sdb_input_readline(char *buf, int *n_chars, size_t max_chars)
 } /* sdb_input_readline */
 
 int
-sdb_input_exec_query()
+sdb_input_exec_query(void)
 {
        char *query = sdb_command_exec(sysdb_input);