shellmatta/src/shellmatta_utils.c

377 lines
12 KiB
C

/*
* Copyright (c) 2019 Stefan Strobel <stefan.strobel@shimatta.net>
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at https://mozilla.org/MPL/2.0/.
*/
/**
* @file shellmatta_utils.c
* @brief util/helper functions of shellmatta
* @author Stefan Strobel <stefan.strobel@shimatta.net>
*/
/**
* @addtogroup shellmatta_utils
* @{
*/
#include "shellmatta_utils.h"
#include "shellmatta.h"
#include <string.h>
/**
* @brief function to write an echo to the output depending on
* the echo enabled state of the instance
* @param[in] inst pointer to a shellmatta instance
* @param[in] data pointer to the data so send
* @param[in] length length of the data to send (in byte)
*/
void utils_writeEcho( shellmatta_instance_t *inst,
const char *data,
uint32_t length)
{
if(true == inst->echoEnabled)
{
inst->write(data, length);
}
}
/**
* @brief itoa like function to convert int to an ascii string
* @warning you have to provide a large enough buffer
* @param[in] value
* @param[in,out] buffer
* @param[in] base
* @return number of bytes in string
*/
uint32_t utils_shellItoa(int32_t value, char *buffer, uint32_t base)
{
char tempBuffer[34u];
uint32_t i;
uint32_t bufferIdx = 0u;
char digitValue;
/** -# check the base for plausibility */
if((2 <= base) && (16 >= base))
{
/** -# check for sign */
if(0 > value)
{
value = value * (-1);
buffer[0u] = '-';
bufferIdx += 1u;
}
/** -# loop through all digits in reverse order */
i = 0u;
do
{
digitValue = (char) (value % base);
tempBuffer[i] = (digitValue < 10) ? ('0' + digitValue) : (('A' - 10) + digitValue);
value /= base;
i ++;
}while(value > 0);
/** -# store the string in the correct order onto the buffer */
while(i > 0u)
{
buffer[bufferIdx] = tempBuffer[i - 1u];
i --;
bufferIdx ++;
}
}
return bufferIdx;
}
/**
* @brief tells the terminal to save the current cursor position
* @param[in] inst pointer to shellmatta instance
*/
void utils_saveCursorPos(shellmatta_instance_t *inst)
{
utils_writeEcho(inst, "\x1b[s", 3u);
}
/**
* @brief tells the terminal to restore the saved cursor position
* @param[in] inst pointer to shellmatta instance
*/
void utils_restoreCursorPos(shellmatta_instance_t *inst)
{
utils_writeEcho(inst, "\x1b[u", 3u);
}
/**
* @brief tells the terminal to erase the line on the right side of the
* cursor
* @param[in] inst pointer to shellmatta instance
*/
void utils_eraseLine(shellmatta_instance_t *inst)
{
utils_writeEcho(inst, "\x1b[K", 3u);
}
/**
* @brief moves the cursor back by the given amoung of characters
* @param[in] inst pointer to shellmatta instance
* @param[in] length number of characters to rewind
*/
void utils_rewindCursor(shellmatta_instance_t *inst, uint32_t length)
{
char terminalCmd[16];
size_t size;
length = SHELLMATTA_MIN (length, inst->cursor);
if(length > 0u)
{
terminalCmd[0] = '\x1b';
terminalCmd[1] = '[';
size = 2u + utils_shellItoa(length, &terminalCmd[2], 10);
terminalCmd[size] = 'D';
utils_writeEcho(inst, terminalCmd, size + 1u);
inst->cursor -= length;
}
}
/**
* @brief moves the cursor forward by the given amoung of characters
* @param[in] inst pointer to shellmatta instance
* @param[in] length number of characters to move forward
*/
void utils_forwardCursor(shellmatta_instance_t *inst, uint32_t length)
{
char terminalCmd[16];
size_t size;
length = SHELLMATTA_MIN (length, (inst->inputCount - inst->cursor));
if (length > 0u)
{
terminalCmd[0] = '\x1b';
terminalCmd[1] = '[';
size = 2u + utils_shellItoa(length, &terminalCmd[2], 10);
terminalCmd[size] = 'C';
utils_writeEcho(inst, terminalCmd, size + 1u);
inst->cursor += length;
}
}
/**
* @brief inserts the given amount of characters at the cursor position
* @param[in] inst pointer to shellmatta instance
* @param[in] data pointer to the data to be inserted
* @param[in] length length of the data to be inserted
* @todo this function shall check buffer overflows
*/
void utils_insertChars( shellmatta_instance_t *inst,
char *data,
uint32_t length)
{
if(0u != length)
{
/** -# check if we have to move chars in the buffer */
if( (inst->cursor != inst->inputCount)
&& (SHELLMATTA_MODE_INSERT == inst->mode))
{
/** -# move the existing chars */
for ( uint32_t i = inst->inputCount;
i > inst->cursor;
i --)
{
inst->buffer[i + length - 1] = inst->buffer[i - 1];
}
/** -# store and print the new chars */
memcpy(&(inst->buffer[inst->cursor]), data, length);
utils_writeEcho(inst, data, length);
/** -# print the other chars and restore the cursor to this position */
utils_eraseLine(inst);
utils_saveCursorPos(inst);
utils_writeEcho( inst,
&(inst->buffer[inst->cursor + length]),
inst->inputCount - inst->cursor);
utils_restoreCursorPos(inst);
inst->cursor += length;
inst->inputCount += length;
}
/** -# overwrite - if the cursor reaches the end of the input it is pushed further */
else
{
memcpy(&(inst->buffer[inst->cursor]), data, length);
utils_writeEcho(inst, data, length);
inst->cursor += length;
if(inst->cursor > inst->inputCount)
{
inst->inputCount = inst->cursor;
}
}
}
}
/**
* @brief removes the given amount of characters from the current cursor
* position
* @param[in] inst pointer to a shellmatta instance
* @param[in] length number of characters to remove
* @param[in] backspace remove characters left of the cursor
*/
void utils_removeChars( shellmatta_instance_t *inst,
uint32_t length,
bool backspace)
{
if(0u != length)
{
/** -# rewind the cursor in case of backspace */
if(true == backspace)
{
length = SHELLMATTA_MIN (length, inst->cursor);
utils_rewindCursor(inst, length);
}
else
{
length = SHELLMATTA_MIN (length, inst->inputCount - inst->cursor);
}
/** -# delete the char at the cursor position */
for ( uint32_t i = inst->cursor;
i < (inst->inputCount - length);
i++)
{
inst->buffer[i] = inst->buffer[i + length];
}
/** -# print the rest of the line again */
utils_eraseLine(inst);
utils_saveCursorPos(inst);
utils_writeEcho( inst,
&(inst->buffer[inst->cursor]),
(inst->inputCount - inst->cursor - length));
utils_restoreCursorPos(inst);
inst->inputCount -= length;
}
}
/**
* @brief clears the input buffer and removes the currend command from
* the terminal output
* @param[in] inst pointer to a shellmatta instance
*/
void utils_clearInput(shellmatta_instance_t *inst)
{
utils_rewindCursor(inst, inst->cursor);
utils_eraseLine(inst);
inst->inputCount = 0u;
inst->dirty = false;
}
/**
* @brief prints all possible commands with description and usage
* @param[in] handle handle shellmatta instance handle
* @param[in] arguments not used here
* @param[in] length not used here
* @return #SHELLMATTA_OK
* #SHELLMATTA_ERROR (buffer overflow)
*/
static shellmatta_retCode_t helpCmdFct(shellmatta_handle_t handle, const char *arguments, uint32_t length)
{
shellmatta_retCode_t ret = SHELLMATTA_OK;
shellmatta_instance_t *inst = (shellmatta_instance_t*) handle;
shellmatta_cmd_t *cmd = inst->cmdList;
size_t maxCmdLen = 0u;
size_t maxCmdAliasLen = 0u;
size_t maxCmdHelpLen = 0u;
size_t cmdLen = 0u;
size_t cmdAliasLen = 0u;
size_t cmdHelpLen = 0u;
uint32_t tabCnt = 0u;
static const char tabBuffer[] = { ' ', ' ', ' ', ' ',
' ', ' ', ' ', ' ',
' ', ' ', ' ', ' ',
' ', ' ', ' ', ' '};
/** -# loop through all commands to determine the lengths of each cmd */
while(NULL != cmd)
{
maxCmdLen = SHELLMATTA_MAX(maxCmdLen, strlen(cmd->cmd));
if(NULL != cmd->cmdAlias)
{
maxCmdAliasLen = SHELLMATTA_MAX(maxCmdAliasLen, strlen(cmd->cmdAlias));
}
if(NULL != cmd->helpText)
{
maxCmdHelpLen = SHELLMATTA_MAX(maxCmdHelpLen, strlen(cmd->helpText));
}
cmd = cmd->next;
}
/** -# loop through all commands and print all possible information */
cmd = inst->cmdList;
while(NULL != cmd)
{
/** -# determine the length of each field to add padding */
cmdLen = strlen(cmd->cmd);
cmdAliasLen = (NULL != cmd->cmdAlias) ? strlen(cmd->cmdAlias) : 0u;
cmdHelpLen = (NULL != cmd->helpText) ? strlen(cmd->helpText) : 0u;
inst->write(cmd->cmd, strlen(cmd->cmd));
tabCnt = (maxCmdLen - cmdLen) + 2u;
SHELLMATTA_PRINT_BUFFER(tabBuffer, tabCnt, inst->write);
if(NULL != cmd->cmdAlias)
{
inst->write(cmd->cmdAlias, cmdAliasLen);
}
tabCnt = (maxCmdAliasLen - cmdAliasLen) + 2u;
SHELLMATTA_PRINT_BUFFER(tabBuffer, tabCnt, inst->write);
if(NULL != cmd->helpText)
{
inst->write(cmd->helpText, cmdHelpLen);
}
tabCnt = (maxCmdHelpLen - cmdHelpLen) + 2u;
SHELLMATTA_PRINT_BUFFER(tabBuffer, tabCnt, inst->write);
if(NULL != cmd->usageText)
{
inst->write(cmd->usageText, strlen(cmd->usageText));
}
inst->write("\r\n", 2u);
cmd = cmd->next;
}
(void)arguments;
(void)length;
return ret;
}
const shellmatta_cmd_t helpCmd = {SHELLMATTA_HELP_COMMAND
, SHELLMATTA_HELP_ALIAS
, SHELLMATTA_HELP_HELP_TEXT
, SHELLMATTA_HELP_USAGE_TEXT
, helpCmdFct
, NULL};
/**
* @brief terminates an input and prints the prompt again
* @param[in] inst pointer to a shellmatta instance
*/
void utils_terminateInput(shellmatta_instance_t *inst)
{
inst->inputCount = 0u;
inst->lastNewlineIdx = 0u;
inst->hereLength = 0u;
inst->cursor = 0u;
inst->stdinIdx = 0u;
inst->stdinLength = 0u;
inst->continuousCmd = NULL;
inst->write("\r\n", 2u);
inst->write(inst->prompt, strlen(inst->prompt));
}
/**
* @}
*/