Split line editing functions into separate file

Move getstring() related stuff into a separate file as a first step on
our way to UTF-8 support for line editing helpers.

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>

1 files changed, 220 insertions, 0 deletions

diff --git a/src/getstring.c b/src/getstring.c
new file mode 100644
index 0000000..4df1d66
--- /dev/null
+++ b/src/getstring.c
@@ -0,0 +1,220 @@
+/*
+ * Calcurse - text-based organizer
+ *
+ * Copyright (c) 2004-2011 calcurse Development Team <misc@calcurse.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the
+ *        following disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the
+ *        following disclaimer in the documentation and/or other
+ *        materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Send your feedback or comments to : misc@calcurse.org
+ * Calcurse home page : http://calcurse.org
+ *
+ */
+
+#include "calcurse.h"
+
+/* Print the string at the desired position. */
+static void
+showstring (WINDOW *win, int x, int y, char *str, int len, int scroff,
+            int curpos)
+{
+  char c = 0;
+
+  /* print string */
+  mvwaddnstr (win, y, x, &str[scroff], -1);
+  wclrtoeol (win);
+
+  /* print scrolling indicator */
+  if (scroff > 0 && scroff < len - col)
+    c = '*';
+  else if (scroff > 0)
+    c = '<';
+  else if (scroff < len - col)
+    c = '>';
+  mvwprintw (win, y, col - 1, "%c", c);
+
+  /* print cursor */
+  wmove (win, y, curpos - scroff);
+
+  if (curpos >= len)
+    waddch (win, SPACE | A_REVERSE);
+  else
+    waddch (win, str[curpos] | A_REVERSE);
+}
+
+/* Delete a character at the given position in string. */
+static void
+del_char (int pos, char *str)
+{
+  str += pos;
+  memmove (str, str + 1, strlen (str) + 1);
+}
+
+/* Add a character at the given position in string. */
+static void
+ins_char (int pos, int ch, char *str)
+{
+  str += pos;
+  memmove (str + 1, str, strlen (str) + 1);
+  *str = ch;
+}
+
+static void
+bell (void)
+{
+  printf ("\a");
+}
+
+/*
+ * Getstring allows to get user input and to print it on a window,
+ * even if noecho() is on. This function is also used to modify an existing
+ * text (the variable string can be non-NULL).
+ * We need to do the echoing manually because of the multi-threading
+ * environment, otherwise the cursor would move from place to place without
+ * control.
+ */
+enum getstr
+getstring (WINDOW *win, char *str, int l, int x, int y)
+{
+  const int pgsize = col / 3;
+
+  int len = strlen (str);
+  int curpos = len;
+  int scroff = 0;
+  int ch;
+
+  custom_apply_attr (win, ATTR_HIGHEST);
+
+  for (;;) {
+    while (curpos < scroff)
+      scroff -= pgsize;
+    while (curpos >= scroff + col - 1)
+      scroff += pgsize;
+
+    showstring (win, x, y, str, len, scroff, curpos);
+    wins_doupdate ();
+
+    if ((ch = wgetch (win)) == '\n') break;
+    switch (ch)
+      {
+        case KEY_BACKSPACE:     /* delete one character */
+        case 330:
+        case 127:
+        case CTRL ('H'):
+          if (curpos > 0)
+            {
+              del_char ((--curpos), str);
+              len--;
+            }
+          else
+            bell ();
+          break;
+        case CTRL ('D'):        /* delete next character */
+          if (curpos < len)
+            {
+              del_char (curpos, str);
+              len--;
+            }
+          else
+            bell ();
+          break;
+        case CTRL ('W'):        /* delete a word */
+          if (curpos > 0) {
+            while (curpos && str[curpos - 1] == ' ')
+              {
+                del_char ((--curpos), str);
+                len--;
+              }
+            while (curpos && str[curpos - 1] != ' ')
+              {
+                del_char ((--curpos), str);
+                len--;
+              }
+          }
+          else
+            bell ();
+          break;
+        case CTRL ('K'):        /* delete to end-of-line */
+          str[curpos] = 0;
+          len = curpos;
+          break;
+        case CTRL ('A'):        /* go to begginning of string */
+          curpos = 0;
+          break;
+        case CTRL ('E'):        /* go to end of string */
+          curpos = len;
+          break;
+        case KEY_LEFT:          /* move one char backward  */
+        case CTRL ('B'):
+          if (curpos > 0) curpos--;
+          break;
+        case KEY_RIGHT:         /* move one char forward */
+        case CTRL ('F'):
+          if (curpos < len) curpos++;
+          break;
+        case ESCAPE:            /* cancel editing */
+          return (GETSTRING_ESC);
+          break;
+        default:                /* insert one character */
+          if (len < l - 1)
+            {
+              ins_char ((curpos++), ch, str);
+              len++;
+            }
+      }
+  }
+
+  custom_remove_attr (win, ATTR_HIGHEST);
+
+  return (len == 0 ? GETSTRING_RET : GETSTRING_VALID);
+}
+
+/* Update an already existing string. */
+int
+updatestring (WINDOW *win, char **str, int x, int y)
+{
+  int len = strlen (*str);
+  char *buf;
+  enum getstr ret;
+
+  EXIT_IF (len + 1 > BUFSIZ, _("Internal error: line too long"));
+
+  buf = mem_malloc (BUFSIZ);
+  (void)memcpy (buf, *str, len + 1);
+
+  ret = getstring (win, buf, BUFSIZ, x, y);
+
+  if (ret == GETSTRING_VALID)
+    {
+      len = strlen (buf);
+      *str = mem_realloc (*str, len + 1, 1);
+      EXIT_IF (*str == NULL, _("out of memory"));
+      (void)memcpy (*str, buf, len + 1);
+    }
+
+  mem_free (buf);
+  return ret;
+}