consoleprogress: New class for writing to the console

Some influence from both systemd and packagekit-glib2.

Makefile-rpm-ostree.am

@@ -20,6 +20,8 @@ bin_PROGRAMS += rpm-ostree
 noinst_LTLIBRARIES += librpmostree.la
 
 librpmostree_la_SOURCES = \
+	src/rpmostree-console-progress.c \
+	src/rpmostree-console-progress.h \
 	src/rpmostree-postprocess.c \
 	src/rpmostree-postprocess.h \
 	src/rpmostree-json-parsing.c \

src/rpmostree-console-progress.c

@@ -0,0 +1,220 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
+ *
+ * Copyright (C) 2013,2014 Colin Walters <walters@verbum.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; either version 2 of the licence or (at
+ * your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General
+ * Public License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include "config.h"
+
+#include "rpmostree-console-progress.h"
+
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+
+static char *current_text = NULL;
+static gint current_percent = -1;
+
+static volatile guint cached_columns = 0;
+static volatile guint cached_lines = 0;
+
+static int
+fd_columns (int fd)
+{
+  struct winsize ws = {};
+
+  if (ioctl (fd, TIOCGWINSZ, &ws) < 0)
+    return -errno;
+
+  if (ws.ws_col <= 0)
+    return -EIO;
+
+  return ws.ws_col;
+}
+
+static guint
+columns (void)
+{
+  if (G_UNLIKELY (cached_columns == 0))
+    {
+      int c;
+
+      c = fd_columns (STDOUT_FILENO);
+
+      if (c <= 0)
+        c = 80;
+
+      if (c > 256)
+        c = 256;
+
+      cached_columns = c;
+    }
+
+  return cached_columns;
+}
+
+#if 0
+static int
+fd_lines (int fd)
+{
+  struct winsize ws = {};
+
+  if (ioctl (fd, TIOCGWINSZ, &ws) < 0)
+    return -errno;
+
+  if (ws.ws_row <= 0)
+    return -EIO;
+
+  return ws.ws_row;
+}
+
+static guint
+lines (void)
+{
+  if (G_UNLIKELY (cached_lines == 0))
+    {
+      int l;
+
+      l = fd_lines (STDOUT_FILENO);
+
+      if (l <= 0)
+        l = 24;
+
+      cached_lines = l;
+    }
+
+  return cached_lines;
+}
+#endif
+
+static void
+on_sigwinch (int signum)
+{
+  cached_columns = 0;
+  cached_lines = 0;
+}
+
+void
+rpmostree_console_progress_start (void)
+{
+  GSConsole *console = gs_console_get ();
+  static gsize sigwinch_initialized = 0;
+
+  if (!console)
+    return;
+  
+  current_percent = 0;
+
+  if (g_once_init_enter (&sigwinch_initialized))
+    {
+      signal (SIGWINCH, on_sigwinch);
+      g_once_init_leave (&sigwinch_initialized, 1);
+    }
+
+  { static const char initbuf[] = { '\n', 0x1B, 0x37 };
+    (void) fwrite (initbuf, 1, sizeof (initbuf), stdout);
+  }
+}
+
+static void
+printpad (const char *padbuf,
+          guint       padbuf_len,
+          guint       n)
+{
+  const guint d = n / padbuf_len;
+  const guint r = n % padbuf_len;
+  guint i;
+
+  for (i = 0; i < d; i++)
+    fwrite (padbuf, 1, padbuf_len, stdout);
+  fwrite (padbuf, 1, r, stdout);
+}
+
+void
+rpmostree_console_progress_text_percent (const char *text,
+                                         guint percentage)
+{
+  static const char equals[] = "====================";
+  const guint n_equals = sizeof (equals) - 1;
+  static const char spaces[] = "                    ";
+  const guint n_spaces = sizeof (spaces) - 1;
+  GSConsole *console = gs_console_get ();
+  const guint ncolumns = columns ();
+  const guint bar_min = 10;
+  const guint input_textlen = text ? strlen (text) : 0;
+  guint textlen;
+  guint barlen;
+
+  if (!console)
+    return;
+
+  g_return_if_fail (percentage <= 100);
+  if (text && !*text)
+    text = NULL;
+
+  if (percentage == current_percent
+      && g_strcmp0 (text, current_text) == 0)
+    return;
+
+  if (ncolumns < bar_min)
+    return; /* TODO: spinner */
+
+  /* Restore cursor */
+  { const char beginbuf[2] = { 0x1B, 0x38 };
+    (void) fwrite (beginbuf, 1, sizeof (beginbuf), stdout);
+  }
+
+  textlen = MIN (input_textlen, ncolumns - bar_min);
+  barlen = ncolumns - textlen;
+
+  if (textlen > 0)
+    {
+      fwrite (text, 1, textlen - 1, stdout);
+      fputc (' ', stdout);
+    }
+  
+  { 
+    const guint nbraces = 2;
+    const guint textpercent_len = 5;
+    const guint bar_internal_len = barlen - nbraces - textpercent_len;
+    const guint eqlen = bar_internal_len * (percentage / 100.0);
+    const guint spacelen = bar_internal_len - eqlen; 
+
+    fputc ('[', stdout);
+    printpad (equals, n_equals, eqlen);
+    printpad (spaces, n_spaces, spacelen);
+    fputc (']', stdout);
+    fprintf (stdout, " %3d%%", percentage);
+  }
+
+  { const guint spacelen = ncolumns - textlen - barlen;
+    printpad (spaces, n_spaces, spacelen);
+  }
+
+  fflush (stdout);
+}
+
+void
+rpmostree_console_progress_end (void)
+{
+  current_percent = -1;
+  g_clear_pointer (&current_text, g_free);
+  fputc ('\n', stdout);
+}

src/rpmostree-console-progress.h

@@ -0,0 +1,42 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
+ *
+ * Copyright (C) 2013,2014 Colin Walters <walters@verbum.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation; either version 2 of the licence or (at
+ * your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General
+ * Public License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#pragma once
+
+#include <libgsystem.h>
+
+G_BEGIN_DECLS
+
+void	 rpmostree_console_progress_start		(void);
+
+void	 rpmostree_console_progress_text_percent        (const char     *text,
+                                                         guint		 percentage);
+
+void	 rpmostree_console_progress_end			(void);
+
+static inline void
+rpmostree_console_progress_cleanup (void **p)
+{
+  rpmostree_console_progress_end ();
+}
+
+#define _cleanup_rpmostree_console_progress_ __attribute__((cleanup(rpmostree_console_progress_cleanup)))
+
+G_END_DECLS