-----Original Message-----
From: acrn-dev@... <acrn-dev@...> On
Behalf Of Minggui Cao
Sent: Wednesday, July 27, 2022 12:55 AM
To: acrn-dev@...
Cc: Cao, Minggui <minggui.cao@...>
Subject: [acrn-dev] [PATCH v4] hv: shell: improve console to buffer history cmds

1. buffer history commands.
2. support up/down key to select history buffered commands

Signed-off-by: Minggui Cao <minggui.cao@...>

[note] will refactor 2nd patch after this one OK.

v3-->v4:
1. improve as Eddie's comments
2. remove move_chars, will use APIs.

v2-->v3:
1. cobile input_line with buffered_cmds as one to buffer/input
2. simplify some logic to handle up/down key

---
hypervisor/debug/shell.c | 122 +++++++++++++++++++++++++---------
hypervisor/debug/shell_priv.h | 10 ++-
2 files changed, 99 insertions(+), 33 deletions(-)

diff --git a/hypervisor/debug/shell.c b/hypervisor/debug/shell.c index
588e4aa0f..5ff72f1ed 100644
--- a/hypervisor/debug/shell.c
+++ b/hypervisor/debug/shell.c
@@ -33,7 +33,6 @@ static char shell_log_buf[SHELL_LOG_BUF_SIZE];
/* Input Line Other - Switch to the "other" input line (there are only two
* input lines total).
*/
-#define SHELL_INPUT_LINE_OTHER(v) (((v) + 1U) & 0x1U)

static int32_t shell_cmd_help(__unused int32_t argc, __unused char **argv);
static int32_t shell_version(__unused int32_t argc, __unused char **argv);
@@ -158,6 +157,14 @@ static struct shell_cmd shell_cmds[] = {
},
};

+/* for function key: up/down key */
+enum function_key {
+ KEY_NONE,
+
+ KEY_UP = 0x5B41,
+ KEY_DOWN = 0x5B42,
+};
+
/* The initial log level*/
uint16_t console_loglevel = CONFIG_CONSOLE_LOGLEVEL_DEFAULT; uint16_t
mem_loglevel = CONFIG_MEM_LOGLEVEL_DEFAULT; @@ -271,14 +278,74
@@ static uint16_t sanitize_vmid(uint16_t vmid)
return sanitized_vmid;
}

+static void clear_input_line(uint32_t len) {
+ while (len > 0) {
+ len--;
+ shell_puts("\b");
+ shell_puts(" \b");
+ }
+}
+
+static void handle_updown_key(enum function_key key_value) {
+ int32_t to_select, current_select = p_shell->to_select_index;
+
+ /* update current_select and p_shell->to_select_index as up/down key
*/
+ if (key_value == KEY_UP) {
+ /* if the ring buffer not full, just decrease one until to 0; if full,
need handle overflow case */
+ to_select = p_shell->to_select_index - 1;
+ if (to_select < 0) {
+ to_select += MAX_BUFFERED_CMDS;
+ }
+
+ if (p_shell->buffered_line[to_select][0] != '\0') {
+ current_select = to_select;
+ }
+
+ } else {
+ /* if down key and current is active line, not need update */
+ if (p_shell->to_select_index != p_shell->input_line_active) {
+ current_select = (p_shell->to_select_index + 1) %
MAX_BUFFERED_CMDS;
+ }
+ }
+
+ /* go up/down until first buffered cmd or current input line: user will
know it is end to select */
+ if (current_select != p_shell->input_line_active) {
+ p_shell->to_select_index = current_select;
+ }
+
+ if (strcmp(p_shell->buffered_line[current_select],
+p_shell->buffered_line[p_shell->input_line_active]) != 0) {
+
+ clear_input_line(p_shell->input_line_len);
+ shell_puts(p_shell->buffered_line[current_select]);
+
+ size_t len = strnlen_s(p_shell->buffered_line[current_select],
+SHELL_CMD_MAX_LEN);
+
+ memcpy_s(p_shell->buffered_line[p_shell->input_line_active],
SHELL_CMD_MAX_LEN,
+ p_shell->buffered_line[current_select], len + 1);
+ p_shell->input_line_len = len;
+ }
+}
+
static void shell_handle_special_char(char ch) {
+ enum function_key key_value = KEY_NONE;
+
switch (ch) {
- /* Escape character */
+ /* original function key value: ESC + key, so consume the next 2
+characters */
case 0x1b:
- /* Consume the next 2 characters */
- (void) shell_getc();
- (void) shell_getc();
+ key_value = (shell_getc() << 8) | shell_getc();
+
+ switch (key_value) {
+ case KEY_UP:
+ case KEY_DOWN:
+ handle_updown_key(key_value);
+ break;
+ default:
+ break;
+ }
+
break;
default:
/*
@@ -308,8 +375,7 @@ static bool shell_input_line(void)
p_shell->input_line_len--;

/* Null terminate the last character to erase it */
- p_shell->input_line[p_shell->input_line_active]
- [p_shell->input_line_len] = 0;
+
+p_shell->buffered_line[p_shell->input_line_active][p_shell->input_line_
+len] = 0;

/* Echo backspace */
shell_puts("\b");
@@ -345,12 +411,10 @@ static bool shell_input_line(void)
/* See if a "standard" prINTable ASCII character
received */
if ((ch >= 32) && (ch <= 126)) {
/* Add character to string */
- p_shell->input_line[p_shell-

input_line_active]

- [p_shell->input_line_len] =
ch;
+
+p_shell->buffered_line[p_shell->input_line_active][p_shell->input_line_
+len] = ch;
/* Echo back the input */
- shell_puts(&p_shell->input_line
- [p_shell->input_line_active]
- [p_shell->input_line_len]);
+ shell_puts(&p_shell->buffered_line[p_shell-

input_line_active]

+ [p_shell->input_line_len]);

/* Move to next character in string */
p_shell->input_line_len++;
@@ -425,33 +489,27 @@ static int32_t shell_process_cmd(const char
*p_input_line)

static int32_t shell_process(void)
{
- int32_t status;
+ int32_t status, former_index;
char *p_input_line;

- /* Check for the repeat command character in active input line.
- */
- if (p_shell->input_line[p_shell->input_line_active][0] == '.') {
- /* Repeat the last command (using inactive input line).
- */
- p_input_line =
- &p_shell->input_line[SHELL_INPUT_LINE_OTHER
- (p_shell->input_line_active)][0];
- } else {
- /* Process current command (using active input line). */
- p_input_line =
- &p_shell->input_line[p_shell->input_line_active][0];
+ /* Process current command (using active input line). */
+ p_input_line = p_shell->buffered_line[p_shell->input_line_active];
+
+ former_index = (p_shell->input_line_active + MAX_BUFFERED_CMDS -
1) %
+MAX_BUFFERED_CMDS;

- /* Switch active input line. */
- p_shell->input_line_active =
- SHELL_INPUT_LINE_OTHER(p_shell-

input_line_active);

+ /* just buffer current cmd if current is not empty and not same with
last buffered one */
+ if ((strnlen_s(p_input_line, SHELL_CMD_MAX_LEN) > 0) &&
+ (strcmp(p_input_line, p_shell-

buffered_line[former_index]) != 0)) {

+ p_shell->input_line_active = (p_shell->input_line_active + 1) %
+MAX_BUFFERED_CMDS;
}

+ p_shell->to_select_index = p_shell->input_line_active;
+
/* Process command */
status = shell_process_cmd(p_input_line);

/* Now that the command is processed, zero fill the input buffer */
- (void)memset((void *) p_shell->input_line[p_shell->input_line_active],
- 0, SHELL_CMD_MAX_LEN + 1U);
+ (void)memset(p_shell->buffered_line[p_shell->input_line_active], 0,
+SHELL_CMD_MAX_LEN + 1U);

/* Process command and return result to caller */
return status;
@@ -490,8 +548,10 @@ void shell_init(void)
p_shell->cmds = shell_cmds;
p_shell->cmd_count = ARRAY_SIZE(shell_cmds);

+ p_shell->to_select_index = 0;
+
/* Zero fill the input buffer */
- (void)memset((void *)p_shell->input_line[p_shell->input_line_active],
0U,
+ (void)memset((void
+*)p_shell->buffered_line[p_shell->input_line_active], 0U,
SHELL_CMD_MAX_LEN + 1U);
}

diff --git a/hypervisor/debug/shell_priv.h b/hypervisor/debug/shell_priv.h index
addad6555..902802b98 100644
--- a/hypervisor/debug/shell_priv.h
+++ b/hypervisor/debug/shell_priv.h
@@ -26,11 +26,17 @@ struct shell_cmd {

};

+#define MAX_BUFFERED_CMDS 8
+
/* Shell Control Block */
struct shell {
- char input_line[2][SHELL_CMD_MAX_LEN + 1U]; /* current & last */
+ /* a ring buffer to buffer former commands and use one as current
active input */
+ char buffered_line[MAX_BUFFERED_CMDS][SHELL_CMD_MAX_LEN +
1U];
uint32_t input_line_len; /* Length of current input line */
- uint32_t input_line_active; /* Active input line index */
+ int32_t input_line_active; /* Active input line index */
+
+ int32_t to_select_index; /* used for up/down key to select former
cmds
+*/
+
struct shell_cmd *cmds; /* cmds supported */
uint32_t cmd_count; /* Count of cmds supported */
};
--
2.25.1