Commit 3d846daa authored by Vasily Gorbik's avatar Vasily Gorbik Committed by Alexander Gordeev
Browse files

s390/boot: Add field width and padding handling to boot_printk() 



Enhance boot_printk() to support field width and padding across all
argument types for better formatting.

Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
Acked-by: default avatarHeiko Carstens <hca@linux.ibm.com>
Signed-off-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
parent 9291d572

arch/s390/boot/printk.c

+50 −18
Original line number Diff line number Diff line
@@ -13,13 +13,37 @@ 


const char hex_asc[] = "0123456789abcdef";



#define MAX_NUMLEN 17

static char *as_hex(char *dst, unsigned long val, int pad)

{

	char *p, *end = p = dst + max(pad, (int)__fls(val | 1) / 4 + 1);

	char *p = dst + max(pad, (int)__fls(val | 1) / 4 + 1);



	for (*p-- = 0; p >= dst; val >>= 4)

	for (*p-- = '\0'; p >= dst; val >>= 4)

		*p-- = hex_asc[val & 0x0f];

	return end;

	return dst;

}



static ssize_t strpad(char *dst, size_t dst_size, const char *src,

		      int _pad, bool zero_pad)

{

	ssize_t len = strlen(src), pad = _pad;

	char *p = dst;



	if (max(len, abs(pad)) >= dst_size)

		return -E2BIG;



	if (pad > len) {

		memset(p, zero_pad ? '0' : ' ', pad - len);

		p += pad - len;

	}

	memcpy(p, src, len);

	p += len;

	if (pad < 0 && -pad > len) {

		memset(p, ' ', -pad - len);

		p += -pad - len;

	}

	*p = '\0';

	return p - dst;

}



static char *symstart(char *p)
@@ -58,22 +82,22 @@ static noinline char *findsym(unsigned long ip, unsigned short *off, unsigned sh 
	return NULL;

}



static noinline char *strsym(void *ip)

#define MAX_SYMLEN 64

static noinline char *strsym(char *buf, void *ip)

{

	static char buf[64];

	unsigned short off;

	unsigned short len;

	char *p;



	p = findsym((unsigned long)ip, &off, &len);

	if (p) {

		strncpy(buf, p, sizeof(buf));

		strncpy(buf, p, MAX_SYMLEN);

		/* reserve 15 bytes for offset/len in symbol+0x1234/0x1234 */

		p = buf + strnlen(buf, sizeof(buf) - 15);

		p = buf + strnlen(buf, MAX_SYMLEN - 15);

		strcpy(p, "+0x");

		p = as_hex(p + 3, off, 0);

		strcpy(p, "/0x");

		as_hex(p + 3, len, 0);

		as_hex(p + 3, off, 0);

		strcat(p, "/0x");

		as_hex(p + strlen(p), len, 0);

	} else {

		as_hex(buf, (unsigned long)ip, 16);

	}
@@ -91,10 +115,13 @@ void boot_printk(const char *fmt, ...) 
{

	char buf[1024] = { 0 };

	char *end = buf + sizeof(buf) - 1; /* make sure buf is 0 terminated */

	unsigned long pad;

	char *p = buf;

	bool zero_pad;

	char *strval, *p = buf;

	char valbuf[MAX(MAX_SYMLEN, MAX_NUMLEN)];

	va_list args;

	char lenmod;

	ssize_t len;

	int pad;



	va_start(args, fmt);

	for (; p < end && *fmt; fmt++) {
@@ -106,7 +133,8 @@ void boot_printk(const char *fmt, ...) 
			*p++ = '%';

			continue;

		}

		pad = isdigit(*fmt) ? simple_strtol(fmt, (char **)&fmt, 10) : 0;

		zero_pad = (*fmt == '0');

		pad = simple_strtol(fmt, (char **)&fmt, 10);

		lenmod = (*fmt == 'h' || *fmt == 'l' || *fmt == 'z') ? *fmt++ : 0;

		if (lenmod == 'h' && *fmt == 'h') {

			lenmod = 'H';
@@ -116,21 +144,25 @@ void boot_printk(const char *fmt, ...) 
		case 's':

			if (lenmod)

				goto out;

			p = buf + strlcat(buf, va_arg(args, char *), sizeof(buf));

			strval = va_arg(args, char *);

			zero_pad = false;

			break;

		case 'p':

			if (*++fmt != 'S' || lenmod)

				goto out;

			p = buf + strlcat(buf, strsym(va_arg(args, void *)), sizeof(buf));

			strval = strsym(valbuf, va_arg(args, void *));

			zero_pad = false;

			break;

		case 'x':

			if (end - p <= max(sizeof(long) * 2, pad))

				goto out;

			p = as_hex(p, va_arg_len_type(args, lenmod, unsigned), pad);

			strval = as_hex(valbuf, va_arg_len_type(args, lenmod, unsigned), 0);

			break;

		default:

			goto out;

		}

		len = strpad(p, end - p, strval, pad, zero_pad);

		if (len == -E2BIG)

			break;

		p += len;

	}

out:

	va_end(args);