libbb/lineedit: implement optional Ctrl-R history search
function old new delta
read_line_input 3433 3957 +524
load_string 77 90 +13
input_tab 1086 1069 -17
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 537/-17) Total: 520 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/libbb/Config.src b/libbb/Config.src
index 0ea8f43..aa44236 100644
--- a/libbb/Config.src
+++ b/libbb/Config.src
@@ -94,6 +94,14 @@
help
Enable history saving in shells.
+config FEATURE_REVERSE_SEARCH
+ bool "Reverse history search"
+ default y
+ depends on FEATURE_EDITING_SAVEHISTORY
+ help
+ Enable readline-like Ctrl-R combination for reverse history search.
+ Increases code by about 0.5k.
+
config FEATURE_TAB_COMPLETION
bool "Tab completion"
default y
diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index 4e3bc0e..1026519 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -207,18 +207,21 @@
#if ENABLE_UNICODE_SUPPORT
-static size_t load_string(const char *src, int maxsize)
+static size_t load_string(const char *src)
{
if (unicode_status == UNICODE_ON) {
- ssize_t len = mbstowcs(command_ps, src, maxsize - 1);
+ ssize_t len = mbstowcs(command_ps, src, S.maxsize - 1);
if (len < 0)
len = 0;
command_ps[len] = BB_NUL;
return len;
} else {
unsigned i = 0;
- while ((command_ps[i] = src[i]) != 0)
+ while (src[i] && i < S.maxsize - 1) {
+ command_ps[i] = src[i];
i++;
+ }
+ command_ps[i] = BB_NUL;
return i;
}
}
@@ -319,9 +322,9 @@
return wc;
}
#else /* !UNICODE */
-static size_t load_string(const char *src, int maxsize)
+static size_t load_string(const char *src)
{
- safe_strncpy(command_ps, src, maxsize);
+ safe_strncpy(command_ps, src, S.maxsize);
return strlen(command_ps);
}
# if ENABLE_FEATURE_TAB_COMPLETION
@@ -1224,10 +1227,10 @@
strcpy(match_buf, &command[cursor_mb]);
/* where do we want to have cursor after all? */
strcpy(&command[cursor_mb], chosen_match + match_pfx_len);
- len = load_string(command, S.maxsize);
+ len = load_string(command);
/* add match and tail */
sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf);
- command_len = load_string(command, S.maxsize);
+ command_len = load_string(command);
/* write out the matched command */
/* paranoia: load_string can return 0 on conv error,
* prevent passing pos = (0 - 12) to redraw */
@@ -1948,6 +1951,140 @@
#undef CTRL
#define CTRL(a) ((a) & ~0x40)
+enum {
+ VI_CMDMODE_BIT = 0x40000000,
+ /* 0x80000000 bit flags KEYCODE_xxx */
+};
+
+#if ENABLE_FEATURE_REVERSE_SEARCH
+/* Mimic readline Ctrl-R reverse history search.
+ * When invoked, it shows the following prompt:
+ * (reverse-i-search)'': user_input [cursor pos unchanged by Ctrl-R]
+ * and typing results in search being performed:
+ * (reverse-i-search)'tmp': cd /tmp [cursor under t in /tmp]
+ * Search is performed by looking at progressively older lines in history.
+ * Ctrl-R again searches for the next match in history.
+ * Backspace deletes last matched char.
+ * Control keys exit search and return to normal editing (at current history line).
+ */
+static int32_t reverse_i_search(void)
+{
+ char match_buf[128]; /* for user input */
+ char read_key_buffer[KEYCODE_BUFFER_SIZE];
+ const char *matched_history_line;
+ const char *saved_prompt;
+ int32_t ic;
+
+ matched_history_line = NULL;
+ read_key_buffer[0] = 0;
+ match_buf[0] = '\0';
+
+ /* Save and replace the prompt */
+ saved_prompt = cmdedit_prompt;
+ goto set_prompt;
+
+ while (1) {
+ int h;
+ unsigned match_buf_len = strlen(match_buf);
+
+ fflush_all();
+//FIXME: correct timeout?
+ ic = lineedit_read_key(read_key_buffer, -1);
+
+ switch (ic) {
+ case CTRL('R'): /* searching for the next match */
+ break;
+
+ case '\b':
+ case '\x7f':
+ /* Backspace */
+ if (unicode_status == UNICODE_ON) {
+ while (match_buf_len != 0) {
+ uint8_t c = match_buf[--match_buf_len];
+ if ((c & 0xc0) != 0x80) /* start of UTF-8 char? */
+ break; /* yes */
+ }
+ } else {
+ if (match_buf_len != 0)
+ match_buf_len--;
+ }
+ match_buf[match_buf_len] = '\0';
+ break;
+
+ default:
+ if (ic < ' '
+ || (!ENABLE_UNICODE_SUPPORT && ic >= 256)
+ || (ENABLE_UNICODE_SUPPORT && ic >= VI_CMDMODE_BIT)
+ ) {
+ goto ret;
+ }
+
+ /* Append this char */
+#if ENABLE_UNICODE_SUPPORT
+ if (unicode_status == UNICODE_ON) {
+ mbstate_t mbstate = { 0 };
+ char buf[MB_CUR_MAX + 1];
+ int len = wcrtomb(buf, ic, &mbstate);
+ if (len > 0) {
+ buf[len] = '\0';
+ if (match_buf_len + len < sizeof(match_buf))
+ strcpy(match_buf + match_buf_len, buf);
+ }
+ } else
+#endif
+ if (match_buf_len < sizeof(match_buf) - 1) {
+ match_buf[match_buf_len] = ic;
+ match_buf[match_buf_len + 1] = '\0';
+ }
+ break;
+ } /* switch (ic) */
+
+ /* Search in history for match_buf */
+ h = state->cur_history;
+ if (ic == CTRL('R'))
+ h--;
+ while (h >= 0) {
+ if (state->history[h]) {
+ char *match = strstr(state->history[h], match_buf);
+ if (match) {
+ state->cur_history = h;
+ matched_history_line = state->history[h];
+ command_len = load_string(matched_history_line);
+ cursor = match - matched_history_line;
+//FIXME: cursor position for Unicode case
+
+ free((char*)cmdedit_prompt);
+ set_prompt:
+ cmdedit_prompt = xasprintf("(reverse-i-search)'%s': ", match_buf);
+ cmdedit_prmt_len = strlen(cmdedit_prompt);
+ goto do_redraw;
+ }
+ }
+ h--;
+ }
+
+ /* Not found */
+ match_buf[match_buf_len] = '\0';
+ beep();
+ continue;
+
+ do_redraw:
+ redraw(cmdedit_y, command_len - cursor);
+ } /* while (1) */
+
+ ret:
+ if (matched_history_line)
+ command_len = load_string(matched_history_line);
+
+ free((char*)cmdedit_prompt);
+ cmdedit_prompt = saved_prompt;
+ cmdedit_prmt_len = strlen(cmdedit_prompt);
+ redraw(cmdedit_y, command_len - cursor);
+
+ return ic;
+}
+#endif
+
/* maxsize must be >= 2.
* Returns:
* -1 on read errors or EOF, or on bare Ctrl-D,
@@ -2062,15 +2199,14 @@
* clutters the big switch a bit, but keeps all the code
* in one place.
*/
- enum {
- VI_CMDMODE_BIT = 0x40000000,
- /* 0x80000000 bit flags KEYCODE_xxx */
- };
int32_t ic, ic_raw;
fflush_all();
ic = ic_raw = lineedit_read_key(read_key_buffer, timeout);
+#if ENABLE_FEATURE_REVERSE_SEARCH
+ again:
+#endif
#if ENABLE_FEATURE_EDITING_VI
newdelflag = 1;
if (vi_cmdmode) {
@@ -2174,6 +2310,11 @@
while (cursor > 0 && !BB_isspace(command_ps[cursor-1]))
input_backspace();
break;
+#if ENABLE_FEATURE_REVERSE_SEARCH
+ case CTRL('R'):
+ ic = ic_raw = reverse_i_search();
+ goto again;
+#endif
#if ENABLE_FEATURE_EDITING_VI
case 'i'|VI_CMDMODE_BIT:
@@ -2327,7 +2468,7 @@
/* Rewrite the line with the selected history item */
/* change command */
command_len = load_string(state->history[state->cur_history] ?
- state->history[state->cur_history] : "", maxsize);
+ state->history[state->cur_history] : "");
/* redraw and go to eol (bol, in vi) */
redraw(cmdedit_y, (state->flags & VI_MODE) ? 9999 : 0);
break;