main.c

来自「uboot详细解读可用启动引导LINUX2.6内核」· C语言 代码 · 共 1,429 行 · 第 1/3 页

#ifdef CONFIG_BOOT_RETRY_TIME
/***************************************************************************
 * initialize command line timeout
 */
void init_cmd_timeout(void)
{
	char *s = getenv ("bootretry");

	if (s != NULL)
		retry_time = (int)simple_strtol(s, NULL, 10);
	else
		retry_time =  CONFIG_BOOT_RETRY_TIME;

	if (retry_time >= 0 && retry_time < CONFIG_BOOT_RETRY_MIN)
		retry_time = CONFIG_BOOT_RETRY_MIN;
}

/***************************************************************************
 * reset command line timeout to retry_time seconds
 */
void reset_cmd_timeout(void)
{
	endtime = endtick(retry_time);
}
#endif

#ifdef CONFIG_CMDLINE_EDITING

/*
 * cmdline-editing related codes from vivi.
 * Author: Janghoon Lyu <[e-mail]>
 */

#define putnstr(str,n)	do {			\
		printf ("%.*s", (int)n, str);	\
	} while (0)

#define CTL_CH(c)		((c) - 'a' + 1)

#define MAX_CMDBUF_SIZE		256

#define CTL_BACKSPACE		('\b')
#define DEL			((char)255)
#define DEL7			((char)127)
#define CREAD_HIST_CHAR		('!')

#define getcmd_putch(ch)	putc(ch)
#define getcmd_getch()		getc()
#define getcmd_cbeep()		getcmd_putch('\a')

#define HIST_MAX		20
#define HIST_SIZE		MAX_CMDBUF_SIZE

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);
}

#ifndef CONFIG_CMDLINE_EDITING
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;
		printf("%s\n", hist_list[i]);
		n++;
		i++;
	}
}
#endif /* CONFIG_CMDLINE_EDITING */

#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(const char *const prompt, 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;
#ifdef CONFIG_BOOT_RETRY_TIME
		while (!tstc()) {	/* while no incoming data */
			if (retry_time >= 0 && get_ticks() > endtime)
				return (-2);	/* timed out */
		}
#endif

		ichar = getcmd_getch();

		if ((ichar == '\n') || (ichar == '\r')) {
			putc('\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 {
				puts("impossible condition #876\n");
				esc_len = 0;
			}
			break;

		case CTL_CH('a'):
			BEGINNING_OF_LINE();
			break;
		case CTL_CH('c'):	/* ^C - break */
			*buf = '\0';	/* discard input */
			return (-1);
		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'):
		case CTL_CH('u'):
			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;
		}
#ifdef CONFIG_AUTO_COMPLETE
		case '\t': {
			int num2, col;

			/* do not autocomplete when in the middle */
			if (num < eol_num) {
				getcmd_cbeep();
				break;
			}

			buf[num] = '\0';
			col = strlen(prompt) + eol_num;
			num2 = num;
			if (cmd_auto_complete(prompt, buf, &num2, &col)) {
				col = num2 - num;
				num += col;
				eol_num += col;
			}
			break;
		}
#endif
		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);
}

#endif /* CONFIG_CMDLINE_EDITING */

/****************************************************************************/

/*
 * Prompt for input and read a line.
 * If  CONFIG_BOOT_RETRY_TIME is defined and retry_time >= 0,
 * time out when time goes past endtime (timebase time in ticks).
 * Return:	number of read characters
 *		-1 if break
 *		-2 if timed out
 */
int readline (const char *const prompt)
{
	return readline_into_buffer(prompt, console_buffer);
}


int readline_into_buffer (const char *const prompt, char * buffer)
{
	char *p = buffer;
#ifdef CONFIG_CMDLINE_EDITING
	unsigned int len=MAX_CMDBUF_SIZE;
	int rc;
	static int initted = 0;

	/*
	 * History uses a global array which is not
	 * writable until after relocation to RAM.
	 * Revert to non-history version if still
	 * running from flash.
	 */
	if (gd->flags & GD_FLG_RELOC) {
		if (!initted) {
			hist_init();
			initted = 1;
		}