add paragraph searching ability

git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@1538 35c25a1d-7b9e-4130-9fde-d3aeb78583b8

ChangeLog

@@ -23,6 +23,12 @@ CVS code -
 	- Add the ability to repeat the last search without prompting
 	  via Meta-W, and move the line wrapping toggle to Meta-L.  New
 	  function do_research(). (Wouter van Hemel)
+	- Added the ability to move to the beginning or end of the
+	  paragraph, which Pico has via ^W^W (previous paragraph)
+	  and ^W^O (next paragraph).  Modifications to do_justify(),
+	  new functions do_para_operation(), do_para_begin(), and
+	  do_para_end().  Note that the last three functions are
+	  disabled if justification is disabled. (DLR)
 - files.c:
   do_browser()
 	- Some of the Pico compatibility options in the file browser

TODO

@@ -3,7 +3,7 @@ TODO file (? means the feature may be implemented, but not definitely)
 
 For version 1.4:
 - UTF-8 support.
-- Support for Pico's paragraph searching ability.
+- Support for Pico's paragraph searching ability. [DONE]
 - Undo/Redo key?
 - Rebindable keys?
 - Keystroke to implement "Add next sequence as raw" like vi's ^V.

global.c

@@ -337,7 +337,8 @@ void shortcut_init(int unjustify)
 	"", *nano_gotodir_msg = "", *nano_case_msg =
 	"", *nano_reverse_msg = "", *nano_execute_msg =
 	"", *nano_dos_msg = "", *nano_mac_msg =
-	"", *nano_backup_msg = "", *nano_editstr_msg = "";
+	"", *nano_backup_msg = "", *nano_editstr_msg =
+	"", *nano_parabegin_msg = "", *nano_paraend_msg = "";
 
 #ifdef ENABLE_MULTIBUFFER
     const char *nano_openprev_msg = "", *nano_opennext_msg =
@@ -395,6 +396,8 @@ void shortcut_init(int unjustify)
     nano_mac_msg = _("Write file out in Mac format");
     nano_backup_msg = _("Back up original file when saving");
     nano_editstr_msg = _("Edit the previous search/replace strings");
+    nano_parabegin_msg = _("Go to the beginning of the current paragraph");
+    nano_paraend_msg = _("Go to the end of the current paragraph");
 #ifdef HAVE_REGEX_H
     nano_regexp_msg = _("Use regular expressions");
     nano_bracket_msg = _("Find other bracket");
@@ -585,44 +588,54 @@ void shortcut_init(int unjustify)
     sc_init_one(&whereis_list, NANO_HELP_KEY, _("Get Help"),
 		IFHELP(nano_help_msg, 0), 0, 0, VIEW, do_help);
 
-    /* Translators: try to keep this string under 12 characters long */
+    /* Translators: try to keep this string under 10 characters long */
     sc_init_one(&whereis_list, NANO_CANCEL_KEY, _("Cancel"),
 		IFHELP(nano_cancel_msg, 0), 0, 0, VIEW, 0);
 
-    /* Translators: try to keep this string under 12 characters long */
+    /* Translators: try to keep this string under 10 characters long */
     sc_init_one(&whereis_list, NANO_FIRSTLINE_KEY, _("First Line"),
 		IFHELP(nano_firstline_msg, 0),
 		0, 0, VIEW, do_first_line);
 
-    /* Translators: try to keep this string under 12 characters long */
+    /* Translators: try to keep this string under 10 characters long */
     sc_init_one(&whereis_list, NANO_LASTLINE_KEY, _("Last Line"),
 		IFHELP(nano_lastline_msg, 0), 0, 0, VIEW, do_last_line);
 
-    /* Translators: try to keep this string under 12 characters long */
+    /* Translators: try to keep this string under 10 characters long */
     sc_init_one(&whereis_list, NANO_OTHERSEARCH_KEY, _("Replace"),
 		IFHELP(nano_replace_msg, 0), 0, 0, VIEW, do_replace);
 
-    /* Translators: try to keep this string under 12 characters long */
+    /* Translators: try to keep this string under 10 characters long */
     sc_init_one(&whereis_list, NANO_FROMSEARCHTOGOTO_KEY, _("Go To Line"),
 		IFHELP(nano_goto_msg, 0), 0, 0, VIEW, do_gotoline_void);
 
+#ifndef DISABLE_JUSTIFY
+    /* Translators: try to keep this string under 10 characters long */
+    sc_init_one(&whereis_list, NANO_PARABEGIN_KEY, _("Beg of Par"),
+		IFHELP(nano_parabegin_msg, 0), 0, 0, VIEW, do_para_begin);
+
+    /* Translators: try to keep this string under 10 characters long */
+    sc_init_one(&whereis_list, NANO_PARAEND_KEY, _("End of Par"),
+		IFHELP(nano_paraend_msg, 0), 0, 0, VIEW, do_para_end);
+#endif
+
 #ifndef NANO_SMALL
-    /* Translators: try to keep this string under 12 characters long */
+    /* Translators: try to keep this string under 10 characters long */
     sc_init_one(&whereis_list, TOGGLE_CASE_KEY, _("Case Sens"),
 		IFHELP(nano_case_msg, 0), 0, 0, VIEW, 0);
 
-    /* Translators: try to keep this string under 12 characters long */
+    /* Translators: try to keep this string under 10 characters long */
     sc_init_one(&whereis_list, TOGGLE_BACKWARDS_KEY, _("Direction"),
 		IFHELP(nano_reverse_msg, 0), 0, 0, VIEW, 0);
 
 #ifdef HAVE_REGEX_H
-    /* Translators: try to keep this string under 12 characters long */
+    /* Translators: try to keep this string under 10 characters long */
     sc_init_one(&whereis_list, TOGGLE_REGEXP_KEY, _("Regexp"),
 		IFHELP(nano_regexp_msg, 0), 0, 0, VIEW, 0);
 #endif
 
 #ifndef NANO_SMALL
-    /* Translators: try to keep this string under 12 characters long */
+    /* Translators: try to keep this string under 10 characters long */
     sc_init_one(&whereis_list, KEY_UP, _("History"),
 		IFHELP(nano_editstr_msg, 0), NANO_UP_KEY, 0, VIEW, 0);
 #endif

nano.c

@@ -2244,17 +2244,17 @@ int break_line(const char *line, int goal, int force)
 	space_loc++;
     return space_loc;
 }
-#endif /* !DISABLE_JUSTIFY */
 
-/* This function justifies the current paragraph. */
-int do_justify(void)
+/* This function performs operations on paragraphs: justify, go to
+ * beginning, and go to end. */
+int do_para_operation(int operation)
 {
-#ifdef DISABLE_JUSTIFY
-    nano_disabled_msg();
-    return 1;
-#else
-
-/* To explain the justifying algorithm, I first need to define some
+/* operation == 0 means we're justifying the paragraph, operation == 1
+ * means we're moving to the beginning line of the paragraph, and
+ * operation == 2 means we're moving to the ending line of the
+ * paragraph.
+ *
+ * To explain the justifying algorithm, I first need to define some
  * phrases about paragraphs and quotation:
  *   A line of text consists of a "quote part", followed by an
  *   "indentation part", followed by text.  The functions quote_length()
@@ -2314,6 +2314,10 @@ int do_justify(void)
     filestruct *line;	/* generic line of text */
     size_t i;		/* generic loop variable */
 
+    static int no_restart = 0;
+    	/* whether we're blocking restarting when searching for the
+    	 * beginning line of the paragraph */
+
 #ifdef HAVE_REGEX_H
     regex_t qreg;	/* qreg is the compiled quotation regexp. 
 			 * We no longer care about quotestr. */
@@ -2333,13 +2337,15 @@ int do_justify(void)
     /* Here is an assumption that is always true anyway. */
     assert(current != NULL);
 
+    current_x = 0;
+
+  restart_bps:
 /* Here we find the first line of the paragraph to justify.  If the
  * current line is in a paragraph, then we move back to the first line. 
  * Otherwise we move down to the first line that is in a paragraph. */
     quote_len = quote_length(IFREG(current->data, &qreg));
     indent_len = indent_length(current->data + quote_len);
 
-    current_x = 0;
     if (current->data[quote_len + indent_len] != '\0') {
 	/* This line is part of a paragraph.  So we must search back to
 	 * the first line of this paragraph.  First we check items 1) and
@@ -2365,6 +2371,25 @@ int do_justify(void)
 	    current = current->prev;
 	    current_y--;
 	}
+    } else if (operation == 1) {
+	/* This line is not part of a paragraph.  Move up until we get
+	 * to a non "blank" line, and then move down once. */
+	do {
+	    /* There is no previous paragraph, so nothing to move to. */
+	    if (current->prev == NULL) {
+		placewewant = 0;
+		if (current_y < 0)
+		    edit_update(current, CENTER);
+		else
+		    edit_refresh();
+		return 0;
+	    }
+	    current = current->prev;
+	    current_y--;
+	    quote_len = quote_length(IFREG(current->data, &qreg));
+	    indent_len = indent_length(current->data + quote_len);
+	} while (current->data[quote_len + indent_len] == '\0');
+	current = current->next;
     } else {
 	/* This line is not part of a paragraph.  Move down until we get
 	 * to a non "blank" line. */
@@ -2410,12 +2435,29 @@ int do_justify(void)
 	par_len++;
     }
 #ifdef HAVE_REGEX_H
-    /* We no longer need to check quotation. */
-    regfree(&qreg);
+    /* We no longer need to check quotation, unless we're searching for
+       the beginning of the paragraph. */
+    if (operation != 1)
+	regfree(&qreg);
 #endif
 /* Now par_len is the number of lines in this paragraph.  Should never
  * call quotes_match() or quote_length() again. */
 
+    /* If operation is nonzero, skip the justification, since we're only
+     * searching through the paragraph.  If operation is 2, move down the
+     * number of lines in the paragraph, so that we end up at the
+     * paragraph's end. */
+    if (operation != 0) {
+	if (operation == 2) {
+	    while (par_len > 0) {
+		current = current->next;
+		current_y++;
+		par_len--;
+	    }
+	}
+	goto skip_justify;
+    }
+
 /* Next step, we loop through the lines of this paragraph, justifying
  * each one individually. */
     SET(JUSTIFY_MODE);
@@ -2572,8 +2614,8 @@ int do_justify(void)
     }
     UNSET(JUSTIFY_MODE);
 
-/* We are now done justifying the paragraph.  There are cleanup things to
- * do, and we check for unjustify. */
+/* We are now done justifying the paragraph.  There are cleanup things
+ * to do, and we check for unjustify. */
 
     /* totlines, totsize, and current_y have been maintained above.  We
      * now set last_par_line to the new end of the paragraph, update
@@ -2586,6 +2628,67 @@ int do_justify(void)
 	renumber(first_mod_line);
     }
 
+  skip_justify:
+    if (operation != 0) {
+	switch (operation) {
+	    case 1:
+		/* We're on the same line we started on.  Search for the
+		 * first non-"blank" line before the line we're on (if
+		 * there is one), continually restart that search from
+		 * the current position until we find a line that's part
+		 * of a paragraph, and then search once more from there,
+		 * so that we end up on the first line of that
+		 * paragraph.  In the process, skip over lines
+		 * consisting only of spacing characters, as searching
+		 * for the end of the paragraph does.  Then update the
+		 * screen. */
+		if (current != fileage && current == current_save &&
+			!no_restart) {
+		    while (current->prev != NULL) {
+			int j, j_space = 0;
+			current = current->prev;
+			current_y--;
+			for (j = 0; j < strlen(current->data); j++) {
+			    if (isspace(current->data[j]))
+				j_space++;
+			    else {
+				j = -1;
+				break;
+			    }
+			}
+			if (j != j_space && strlen(current->data) >=
+				(quote_len + indent_len) &&
+				current->data[quote_len + indent_len] != '\0') {
+			    no_restart = 1;
+			    break;
+			}
+		    }
+		    goto restart_bps;
+		} else
+		    no_restart = 0;
+#ifdef HAVE_REGEX_H
+		/* We no longer need to check quotation, if we were
+		   searching for the beginning of the paragraph. */
+		regfree(&qreg);
+#endif
+		if (current_y < 0)
+		    edit_update(current, CENTER);
+		else
+		    edit_refresh();
+		break;
+	    case 2:
+		/* We've already moved to the end of the paragraph.
+		 * Update the screen. */
+		if (current_y > editwinrows - 1)
+		    edit_update(current, CENTER);
+		else
+		    edit_refresh();
+		break;
+	}
+	if (operation != 0)
+	    return 0;
+    }
+
     if (current_y > editwinrows - 1)
 	edit_update(current, CENTER);
     else
@@ -2663,9 +2766,31 @@ int do_justify(void)
     display_main_list();
 
     return 0;
+}
+#endif /* !DISABLE_JUSTIFY */
+
+int do_justify(void)
+{
+#ifdef DISABLE_JUSTIFY
+    nano_disabled_msg();
+    return 1;
+#else
+    return do_para_operation(0);
 #endif
 }
 
+#ifndef DISABLE_JUSTIFY
+int do_para_begin(void)
+{
+    return do_para_operation(1);
+}
+
+int do_para_end(void)
+{
+    return do_para_operation(2);
+}
+#endif
+
 int do_exit(void)
 {
     int i;

nano.h

@@ -389,6 +389,8 @@ know what you're doing */
 #define NANO_EXTCMD_KEY		NANO_CONTROL_X
 #define NANO_NEXTWORD_KEY	NANO_CONTROL_SPACE
 #define NANO_PREVWORD_KEY	NANO_ALT_SPACE
+#define NANO_PARABEGIN_KEY	NANO_CONTROL_W
+#define NANO_PARAEND_KEY	NANO_CONTROL_O
 
 #ifndef NANO_SMALL
 /* Toggles do not exist with NANO_SMALL. */

proto.h

@@ -311,8 +311,13 @@ filestruct *backup_lines(filestruct *first_line, size_t par_len,
 			size_t quote_len);
 int breakable(const char *line, int goal);
 int break_line(const char *line, int goal, int force);
+int do_para_operation(int operation);
 #endif /* !DISABLE_JUSTIFY */
 int do_justify(void);
+#ifndef DISABLE_JUSTIFY
+int do_para_begin(void);
+int do_para_end(void);
+#endif
 int do_exit(void);
 void signal_init(void);
 RETSIGTYPE handle_hupterm(int signal);

winio.c

@@ -1447,6 +1447,16 @@ int statusq(int tabs, const shortcut *s, const char *def,
 	do_last_line();
 	resetstatuspos = 1;
 	break;
+#ifndef DISABLE_JUSTIFY
+    case NANO_PARABEGIN_KEY:
+	do_para_begin();
+	resetstatuspos = 1;
+	break;
+    case NANO_PARAEND_KEY:
+	do_para_end();
+	resetstatuspos = 1;
+	break;
+#endif
     case NANO_CANCEL_KEY:
 	ret = -1;
 	resetstatuspos = 1;