getcmd_ext.c

在LINUX中实现USB摄像头视频监控的完整源代码!全部是自己移值的

/*
 * vivi/drivers/serial/getcmd_ex.c: extended getcmd()
 *
 * Based on bootldr/getcmd.c
 *
 * Author: Janghoon Lyu <[e-mail]>
 * Date  : $Date: 2004/02/04 06:22:25 $
 *
 * $Revision: 1.1.1.1 $
 */

#include <config.h>
#include "getcmd.h"
#include <serial.h>
#include <printk.h>
#include <command.h>

#include <types.h>
#include <string.h>

static int hist_max = 0;
static int hist_add_idx = 0;
static int hist_cur = -1;
unsigned hist_num = 0;

char* hist_list[HIST_MAX];
char hist_lines[HIST_MAX][HIST_SIZE];

#define add_idx_minus_one() ((hist_add_idx == 0) ? hist_max : hist_add_idx-1)

static void 
hist_init(void)
{
	int i;

	hist_max = 0;
	hist_add_idx = 0;
	hist_cur = -1;
	hist_num = 0;

	for (i = 0; i < HIST_MAX; i++) {
		hist_list[i] = hist_lines[i];
		hist_list[i][0] = '\0';
	}
}

static void 
cread_add_to_hist(char *line)
{
	strcpy(hist_list[hist_add_idx], line);

	if (++hist_add_idx >= HIST_MAX)
		hist_add_idx = 0;

	if (hist_add_idx > hist_max)
		hist_max = hist_add_idx;

	hist_num++;
}

static char*
hist_prev(void)
{
	char *ret;
	int old_cur;

	if (hist_cur < 0)
		return NULL;

	old_cur = hist_cur;
	if (--hist_cur < 0)
		hist_cur = hist_max;

	if (hist_cur == hist_add_idx) {
		hist_cur = old_cur;
		ret = NULL;
	} else
		ret = hist_list[hist_cur];

	return (ret);
}

static char* 
hist_next(void)
{
	char *ret;

	if (hist_cur < 0)
		return NULL;

	if (hist_cur == hist_add_idx)
		return NULL;

	if (++hist_cur > hist_max)
		hist_cur = 0;

	if (hist_cur == hist_add_idx) {
		ret = "";
	} else
		ret = hist_list[hist_cur];

	return (ret);
}

static void 
cread_print_hist_list(void)
{
	int i;
	unsigned long n;

	n = hist_num - hist_max;

	i = hist_add_idx + 1;
	while (1) {
		if (i > hist_max)
			i = 0;
		if (i == hist_add_idx)
			break;
		printk("%s\n", hist_list[i]);
		n++;
		i++;
	}
}

#define BEGINNING_OF_LINE() {			\
	while (num) {				\
		getcmd_putch(CTL_BACKSPACE);	\
		num--;				\
	}					\
}

#define ERASE_TO_EOL() {				\
	if (num < eol_num) {				\
		int tmp;				\
		for (tmp = num; tmp < eol_num; tmp++)	\
			getcmd_putch(' ');		\
		while (tmp-- > num)			\
			getcmd_putch(CTL_BACKSPACE);	\
		eol_num = num;				\
	}						\
}

#define REFRESH_TO_EOL() {			\
	if (num < eol_num) {			\
		wlen = eol_num - num;		\
		putnstr(buf + num, wlen);	\
		num = eol_num;			\
	}					\
}	

static void 
cread_add_char(char ichar, int insert, unsigned long *num, 
               unsigned long *eol_num, char *buf, unsigned long len)
{
	unsigned long wlen;

	/* room ??? */
	if (insert || *num == *eol_num) {
		if (*eol_num > len - 1) {
			getcmd_cbeep();
			return;
		}
		(*eol_num)++;
	}

	if (insert) {
		wlen = *eol_num - *num;
		if (wlen > 1) {
			memmove(&buf[*num+1], &buf[*num], wlen-1);
		}

		buf[*num] = ichar;
		putnstr(buf + *num, wlen);
		(*num)++;
		while (--wlen) {
			getcmd_putch(CTL_BACKSPACE);
		}
	} else {
		/* echo the character */
		wlen = 1;
		buf[*num] = ichar;
		putnstr(buf + *num, wlen);
		(*num)++;
	}
}

static void 
cread_add_str(char *str, int strsize, int insert, unsigned long *num,
              unsigned long *eol_num, char *buf, unsigned long len)
{
	while (strsize--) {
		cread_add_char(*str, insert, num, eol_num, buf, len);
		str++;
	}
}

static int
cread_line(char *buf, unsigned int *len)
{
	unsigned long num = 0;
	unsigned long eol_num = 0;
	unsigned long rlen;
	unsigned long wlen;
	char ichar;
	int insert = 1;
	int esc_len = 0;
	int rc = 0;
	char esc_save[8];

	while (1) {
		rlen = 1;
		ichar = getcmd_getch();

		if ((ichar == '\n') || (ichar == '\r')) {
			printk("\n");
			break;
		}

		/*
		 * handle standard linux xterm esc sequences for arrow key, etc.
		 */
		if (esc_len != 0) {
			if (esc_len == 1) {
				if (ichar == '[') {
					esc_save[esc_len] = ichar;
					esc_len = 2;
				} else {
					cread_add_str(esc_save, esc_len, insert,
						      &num, &eol_num, buf, *len);
					esc_len = 0;
				}
				continue;
			}

			switch (ichar) {

			case 'D':	/* <- key */
				ichar = CTL_CH('b');
				esc_len = 0;
				break;
			case 'C':	/* -> key */
				ichar = CTL_CH('f');
				esc_len = 0;
				break;	/* pass off to ^F handler */
			case 'H':	/* Home key */
				ichar = CTL_CH('a');
				esc_len = 0;
				break;	/* pass off to ^A handler */
			case 'A':	/* up arrow */
				ichar = CTL_CH('p');
				esc_len = 0;
				break;	/* pass off to ^P handler */
			case 'B':	/* down arrow */
				ichar = CTL_CH('n');
				esc_len = 0;
				break;	/* pass off to ^N handler */
			default:
				esc_save[esc_len++] = ichar;
				cread_add_str(esc_save, esc_len, insert,
					      &num, &eol_num, buf, *len);
				esc_len = 0;
				continue;
			}
		}

		switch (ichar) {
			case 0x1b:
				if (esc_len == 0) {
					esc_save[esc_len] = ichar;
					esc_len = 1;
				} else {
					printk("impossible condition #876\n");
					esc_len = 0;
				}
				break;

			case CTL_CH('a'):
				BEGINNING_OF_LINE();
				break;
			case CTL_CH('f'):
				if (num < eol_num) {
					getcmd_putch(buf[num]);
					num++;
				}
				break;
			case CTL_CH('b'):
				if (num) {
					getcmd_putch(CTL_BACKSPACE);
					num--;
				}
				break;
			case CTL_CH('d'):
				if (num < eol_num) {
					wlen = eol_num - num - 1;
					if (wlen) {
						memmove(&buf[num], &buf[num+1], wlen);
						putnstr(buf + num, wlen);
					}

					getcmd_putch(' ');
					do {
						getcmd_putch(CTL_BACKSPACE);
					} while (wlen--);
					eol_num--;
				}
				break;
			case CTL_CH('k'):
				ERASE_TO_EOL();
				break;
			case CTL_CH('e'):
				REFRESH_TO_EOL();
				break;
			case CTL_CH('o'):
				insert = !insert;
				break;
			case CTL_CH('x'):
				BEGINNING_OF_LINE();
				ERASE_TO_EOL();
				break;
			case DEL:
			case DEL7:
			case 8:
				if (num) {
					wlen = eol_num - num;
					num--;
					memmove(&buf[num], &buf[num+1], wlen);
					getcmd_putch(CTL_BACKSPACE);
					putnstr(buf + num, wlen);
					getcmd_putch(' ');
					do {
						getcmd_putch(CTL_BACKSPACE);
					} while (wlen--);
					eol_num--;
				}
				break;
			case CTL_CH('p'):
			case CTL_CH('n'):
				{
				char * hline;

				esc_len = 0;

				if (ichar == CTL_CH('p'))
					hline = hist_prev();
				else
					hline = hist_next();

				if (!hline) {
					getcmd_cbeep();
					continue;
				}

				/* nuke the current line */
				/* first, go home */
				BEGINNING_OF_LINE();

				/* erase to end of line */
				ERASE_TO_EOL();

				/* copy new line into place and display */
				strcpy(buf, hline);
				eol_num = strlen(buf);
				REFRESH_TO_EOL();
				continue;
				}
			default:
				cread_add_char(ichar, insert,
					       &num, &eol_num, buf, *len);
				break;
		}
	}
	*len = eol_num;
	buf[eol_num] = '\0';	/* lose the newline */

	if (buf[0] && buf[0] != CREAD_HIST_CHAR)
		cread_add_to_hist(buf);
	hist_cur = hist_add_idx;

	return (rc);
}

void 
getcmd(char *buf, unsigned int len)
{
	static int initted = 0;

	if (!initted) {
		hist_init();
		initted = 1;
	}

	cread_line(buf, &len);
}