bash-ctrlr: Improve reverse bash search performance

Remove hack that only starts searching when two chars have been entered

Improve performance by adding LIMIT clause instead.

README.md

@@ -2,15 +2,33 @@
 hs9001 (history search 9001) is an easy, quite simple bash history enhancement. It simply writes all
 your bash commands into an sqlite database. You can then search this database.
 
+It improves over bash's built-in history mechanism as it'll aggregate the shell history of all open shells,
+timestamp them and also record additional information such as the directory a command was executed in.
+
+## Usage / Examples
+### Search
+
+```
+hs [search terms]
+```
+You can further filter with options like `-cwd`, `-after` and so on...
+For a full list, see `-help`.
+
+```
+hs -cwd . 
+``` 
+Lists all commands ever entered in this directory
+
+```
+hs -after yesterday -cwd . git
+``` 
+Lists all git commands in the current directory which have been entered today.
+
+Also, it (by default) replaces bash's built-in CTRL-R mechanism, so hs9001's database will be used instead
+of bash's limited history files. 
 
 ## Install
 
-### From source
-```
-go build
-#move hs9001 to a PATH location
-```
-
 ### Debian / Ubuntu
 Latest release can be installed using apt
 ```
@@ -28,31 +46,26 @@ apk update
 apk add hs9001
 ```
 
+### From source
+```
+go build
+#move hs9001 to a PATH location
+```
 
-### Setup / Config
+## Setup / Config
 
 Add this to .bashrc
 
 ```
 eval "$(hs9001 bash-enable)"
 ```
+
+This will also create a `hs`alias so you have to type less in everyday usage.
+
 By default, every system user gets his own database. You can override this by setting the environment variable
 for all users that should write to your unified database.
-
 ```
 export HS9001_DB_PATH="/home/db/history.sqlite"
 ```
 
-## Usage
-### Search
-
-```
-hs9001 search [search terms]
-```
-
-It is recommended to create an alias for search to make life easier, e. g.:
-
-```
-alias searchh='hs9001 search'
-```
 

history.go

@@ -12,16 +12,15 @@ type history struct {
 }
 
 func (h *history) GetHistoryByPrefix(prefix string) (ph []string) {
-	/* Hack for performance reasons */
-	if len(prefix) < 2 {
-		return
-	}
 	opts := searchopts{}
-	opts.order = "DESC"
+	o := "DESC"
+	opts.order = &o
+	lim := 100
+	opts.limit = &lim
 	cmdqry := prefix + "%"
 	opts.command = &cmdqry
 	results := search(h.conn, opts)
-	for e := results.Front(); e != nil; e = e.Next() {
+	for e := results.Back(); e != nil; e = e.Prev() {
 		entry, ok := e.Value.(*HistoryEntry)
 		if !ok {
 			log.Panic("Failed to retrieve entries")
@@ -31,16 +30,15 @@ func (h *history) GetHistoryByPrefix(prefix string) (ph []string) {
 	return
 }
 func (h *history) GetHistoryByPattern(pattern string) (ph []string, pos []int) {
-	/* Hack for performance reasons */
-	if len(pattern) < 2 {
-		return
-	}
 	opts := searchopts{}
-	opts.order = "DESC"
+	o := "DESC"
+	opts.order = &o
+	lim := 100
+	opts.limit = &lim
 	cmdqry := "%" + pattern + "%"
 	opts.command = &cmdqry
 	results := search(h.conn, opts)
-	for e := results.Front(); e != nil; e = e.Next() {
+	for e := results.Back(); e != nil; e = e.Prev() {
 		entry, ok := e.Value.(*HistoryEntry)
 		if !ok {
 			log.Panic("Failed to retrieve entries")

main.go

@@ -157,7 +157,8 @@ type searchopts struct {
 	after   *time.Time
 	before  *time.Time
 	retval  *int
-	order   string
+	order   *string
+	limit   *int
 }
 
 func search(conn *sql.DB, opts searchopts) list.List {
@@ -188,7 +189,18 @@ func search(conn *sql.DB, opts searchopts) list.List {
 		args = append(args, opts.retval)
 	}
 	sb.WriteString("ORDER BY timestamp ")
-	sb.WriteString("ASC ")
+	if opts.order != nil {
+		sb.WriteString(*opts.order)
+		sb.WriteRune(' ')
+	} else {
+		sb.WriteString("ASC ")
+	}
+
+	if opts.limit != nil {
+		sb.WriteString("LIMIT ")
+		sb.WriteString(strconv.Itoa(*opts.limit))
+		sb.WriteRune(' ')
+	}
 
 	queryStmt := sb.String()
 
@@ -309,6 +321,7 @@ func main() {
 				PROMPT_COMMAND='hs9001 add -ret $? "$(history 1)"'
 				bind -x '"\C-r": " READLINE_LINE=$(hs9001 bash-ctrlr 3>&1 1>&2 2>&3) READLINE_POINT=0"'
 			fi
+			alias hs='hs9001 search'
 		`)
 	case "bash-disable":
 		fmt.Printf("unset PROMPT_COMMAND\n")
@@ -352,7 +365,8 @@ func main() {
 		q := strings.Join(args, " ")
 
 		opts := searchopts{}
-		opts.order = "ASC"
+		o := "ASC"
+		opts.order = &o
 		if q != "" {
 			cmd := "%" + q + "%"
 			opts.command = &cmd