Minor change for new isearch code

Minor change for new isearch code

[Wayne Davison]

Here's a minor tweak for the incremental search code based on my last
patch.  It just makes the startup case where you begin the search from
somewhere in the history a little more efficient by using the metafied
history entry directly rather than building one from "line".

Index: zle_hist.c
@@ -637,7 +637,7 @@
 	s = curhistline = metafy(UTOSCP(line), ll, META_DUP);
     }
     else
-	s = metafy(UTOSCP(line), ll, META_USEHEAP);
+	s = qgetevent(histline);
     bindtab = mainbindtab;
     pos = metalen(s, cs);
     for (;;) {

..wayne..

Re: Minor change for new isearch code

[Zoltan Hidvegi]

[-- Attachment #1: Type: application/pgp, Size: 5198 bytes --]

Re: Minor change for new isearch code

[Wayne Davison]

Zoltan Hidvegi writes:
> If I go back in the history, modify a line and start an isearch the
> modifications will disappear.

This is actually a more widespread problem in zsh than just the isearch
code.  If I start to edit a history line and go to another history line
via something like Ctrl-P (previous line in emacs mode) my modifications
will also disappear.  I would like to see this fixed for all functions.

How about this.  Unapply your last patch to zle_hist.c and apply this one
instead.  This code creates a function remember_edits() that remembers
the edits to whatever history line we're on and stashes the real history
line in a linked list for later retrieval (I used a linked list just
because it was memory efficient).  When the user presses return a new
function called forget_edits() restores all the edited history lines to
their original values.

I put a call to remember_edits() in quite a few functions in zle_hist.c,
but if you like this code, there are undoubtedly more functions that will
need to call it.  Also, there may be other functions besides the ones
that had "accept" in their name that require the forget_edits() call.

..wayne..
---8<------8<------8<------8<---cut here--->8------>8------>8------>8---
Index: zle_hist.c
@@ -32,6 +32,62 @@
 #define ZLE
 #include "zsh.h"
 
+struct modified {
+    struct modified *next;
+    char *text;
+    int histnum;
+} *hist_mods;
+
+/**/
+void
+remember_edits(void)
+{
+    if (histline == curhist) {
+	zsfree(curhistline);
+	curhistline = metafy(UTOSCP(line), ll, META_DUP);
+    }
+    else {
+	struct modified *node = hist_mods, *prev = NULL;
+	Histent ent = gethistent(histline);
+
+	while (node && node->histnum < histline) {
+	    prev = node;
+	    node = node->next;
+	}
+	if (!node || node->histnum != histline) {
+	    struct modified *newnode = (struct modified *)zalloc(sizeof *node);
+
+	    newnode->next = node;
+	    newnode->histnum = histline;
+	    newnode->text = ent->text;
+	    if (!prev)
+		hist_mods = newnode;
+	    else
+		prev->next = newnode;
+	} else
+	    free(ent->text);
+
+	ent->text = metafy(UTOSCP(line), ll, META_DUP);
+    }
+}
+
+/**/
+void
+forget_edits(void)
+{
+    struct modified *node, *next;
+    Histent ent;
+
+    for (node = hist_mods; node; node = next) {
+	next = node->next;
+	ent = gethistent(node->histnum);
+	free(ent->text);
+	ent->text = node->text;
+	free((char*)node);
+    }
+    hist_mods = NULL;
+}
+
 /**/
 void
 uphistory(void)
@@ -43,10 +99,7 @@
 	downhistory();
 	return;
     }
-    if (histline == curhist) {
-	zsfree(curhistline);
-	curhistline = metafy(UTOSCP(line), ll, META_DUP);
-    }
+    remember_edits();
     histline -= mult;
     if (!(s = qgetevent(histline))) {
 	if (unset(NOHISTBEEP))
@@ -281,6 +334,7 @@
 {
     char *s;
 
+    forget_edits();
     if (!(s = qgetevent(histline + 1))) {
 	feep();
 	return;
@@ -301,6 +355,7 @@
 	uphistory();
 	return;
     }
+    remember_edits();
     histline += mult;
     if (!(s = qgetevent(histline))) {
 	if (unset(NOHISTBEEP))
@@ -320,10 +375,7 @@
     int t0, ohistline = histline;
     char *s;
 
-    if (histline == curhist) {
-	zsfree(curhistline);
-	curhistline = metafy(UTOSCP(line), ll, META_DUP);
-    }
+    remember_edits();
     if (lastcmd & ZLE_HISTSEARCH)
 	t0 = histpos;
     else {
@@ -353,10 +405,7 @@
     int t0, ohistline = histline;
     char *s;
 
-    if (histline == curhist) {
-	zsfree(curhistline);
-	curhistline = metafy(UTOSCP(line), ll, META_DUP);
-    }
+    remember_edits();
     if (lastcmd & ZLE_HISTSEARCH)
 	t0 = histpos;
     else {
@@ -395,10 +444,7 @@
 {
     char *s;
 
-    if (histline == curhist) {
-	zsfree(curhistline);
-	curhistline = metafy(UTOSCP(line), ll, META_DUP);
-    }
+    remember_edits();
     if (!(s = qgetevent(firsthist()))) {
 	if (unset(NOHISTBEEP))
 	    feep();
@@ -632,12 +678,8 @@
 
     strcpy(ibuf, ISEARCH_PROMPT);
     memcpy(ibuf + NORM_PROMPT_POS, (dir == 1) ? "fwd" : "bck", 3);
-    if (histline == curhist) {
-	zsfree(curhistline);
-	s = curhistline = metafy(UTOSCP(line), ll, META_DUP);
-    }
-    else
-	s = qgetevent(histline);
+    remember_edits();
+    s = qgetevent(histline);
     bindtab = mainbindtab;
     pos = metalen(s, cs);
     for (;;) {
@@ -834,6 +876,7 @@
     int t0;
     char *s;
 
+    forget_edits();
     done = 1;
     for (t0 = histline - 2;; t0--) {
 	if (!(s = qgetevent(t0)))
@@ -1024,10 +1067,7 @@
 	return;
     }
     t0 = strlen(visrchstr);
-    if (histline == curhist) {
-	zsfree(curhistline);
-	curhistline = metafy(UTOSCP(line), ll, META_DUP);
-    }
+    remember_edits();
     for (;;) {
 	histline += visrchsense;
 	if (!(s = qgetevent(histline))) {
@@ -1067,10 +1107,7 @@
     int ohistline = histline;
     char *s;
 
-    if (histline == curhist) {
-	zsfree(curhistline);
-	curhistline = metafy(UTOSCP(line), ll, META_DUP);
-    }
+    remember_edits();
     for (;;) {
 	histline--;
 	if (!(s = qgetevent(histline))) {
@@ -1098,10 +1135,7 @@
     int ohistline = histline;
     char *s;
 
-    if (histline == curhist) {
-	zsfree(curhistline);
-	curhistline = metafy(UTOSCP(line), ll, META_DUP);
-    }
+    remember_edits();
     for (;;) {
 	histline++;
 	if (!(s = qgetevent(histline))) {
Index: zle_misc.c
@@ -256,6 +256,7 @@
 void
 acceptline(void)
 {
+    forget_edits();
     done = 1;
 }
 
@@ -265,6 +266,7 @@
 {
     pushnode(bufstack, ztrdup((char *)line));
     stackcs = cs;
+    forget_edits();
     done = 1;
 }
 
---8<------8<------8<------8<---cut here--->8------>8------>8------>8---

Re: Minor change for new isearch code

[Zoltan Hidvegi]

[-- Attachment #1: Type: application/pgp, Size: 14747 bytes --]

Re: Minor change for new isearch code

[Wayne Davison]

Zoltan Hidvegi writes:
> Here is a complete revision of the patches in articles 1062 and 1063
> from Wayne.

Fair enough.  You missed a couple strlen() -> ztrlen() changes
in the history-search-* functions, however.  BUT, since your
new metadiffer() function can differentiate between an exact match
and a substring match, the ztrlen() call isn't even needed if we
disallow the 0 return value.  My patch is appended.

This patch also corrects a minor typo in the comment prior to
metadiffer() and moves the assignment of histpos (a trivial
optimization).

..wayne..
---8<------8<------8<------8<---cut here--->8------>8------>8------>8---
Index: utils.c
@@ -2948,7 +2948,7 @@
 	return 1;
 }
 
-/* Return zero if the metafied string s differs and the non-metafied, *
+/* Return zero if the metafied string s and the non-metafied,         *
  * len-long string r are the same.  Return -1 if r is a prefix of s   *
  * and return 1 otherwise.                                            */
 
Index: zle_hist.c
@@ -355,8 +355,8 @@
 	for (t0 = 0; t0 < ll && !iblank(line[t0]); t0++);
 	if (t0 < ll)
 	    t0++;
+	histpos = t0;
     }
-    histpos = t0;
     for (;;) {
 	histline--;
 	if (!(s = zle_get_event(histline))) {
@@ -364,8 +364,7 @@
 	    histline = ohistline;
 	    return;
 	}
-	if (strlen(UTOSCP(s)) > t0 &&
-	    metadiffer(s, UTOSCP(line), t0) < 1 &&
+	if (metadiffer(s, UTOSCP(line), t0) < 0 &&
 	    metadiffer(s, UTOSCP(line), ll))
 	    break;
     }
@@ -386,8 +385,8 @@
 	for (t0 = 0; t0 < ll && !iblank(line[t0]); t0++);
 	if (t0 < ll)
 	    t0++;
+	histpos = t0;
     }
-    histpos = t0;
     for (;;) {
 	histline++;
 	if (!(s = zle_get_event(histline))) {
@@ -395,8 +394,7 @@
 	    histline = ohistline;
 	    return;
 	}
-	if ((histline == curhist || strlen(UTOSCP(s)) > t0) && 
-	    metadiffer(s, UTOSCP(line), t0) < 1 &&
+	if (metadiffer(s, UTOSCP(line), t0) < (histline == curhist) &&
 	    metadiffer(s, UTOSCP(line), ll))
 	    break;
     }
@@ -1101,8 +1099,7 @@
 	    histline = ohistline;
 	    return;
 	}
-	if (ztrlen((char *)s) > cs &&
-	    metadiffer(s, (char *)line, cs) < 1 &&
+	if (metadiffer(s, (char *)line, cs) < 0 &&
 	    metadiffer(s, (char *)line, ll))
 	    break;
     }
@@ -1130,8 +1127,7 @@
 	    histline = ohistline;
 	    return;
 	}
-	if ((histline == curhist || ztrlen((char *)s) > cs) &&
-	    metadiffer(s, (char *)line, cs) < 1 &&
+	if (metadiffer(s, (char *)line, cs) < (histline == curhist) &&
 	    metadiffer(s, (char *)line, ll))
 	    break;
     }
---8<------8<------8<------8<---cut here--->8------>8------>8------>8---