Hi,
I always stumble upon missing zero-padding every time I do something in
the bootloader. This time I really need it so that I can load a file
depending on a number. The files are named %02x-%02x-%02x if you were
wondering.
This implements the bare minimum to make it work. I don't claim it
fulfills a specific standard. It's based on the code in our kernel
printf.
Opinions?
Patrick
diff --git a/sys/lib/libsa/printf.c b/sys/lib/libsa/printf.c
index 0b3b5402a55..c48d31fb0a8 100644
--- a/sys/lib/libsa/printf.c
+++ b/sys/lib/libsa/printf.c
@@ -60,9 +60,16 @@
#include "stand.h"
-void kprintn(void (*)(int), u_long, int);
+/*
+ * macros for converting digits to letters and vice versa
+ */
+#define to_digit(c) ((c) - '0')
+#define is_digit(c) ((unsigned)to_digit(c) <= 9)
+#define to_char(n) ((n) + '0')
+
+void kprintn(void (*)(int), u_long, int, int);
#ifdef LIBSA_LONGLONG_PRINTF
-void kprintn64(void (*)(int), u_int64_t, int);
+void kprintn64(void (*)(int), u_int64_t, int, int);
#endif
void kdoprnt(void (*)(int), const char *, va_list);
@@ -91,7 +98,7 @@ kdoprnt(void (*put)(int), const char *fmt, va_list ap)
u_int64_t ull;
#endif
unsigned long ul;
- int ch, lflag;
+ int ch, lflag, zeropad, width, n;
char *p;
for (;;) {
@@ -101,10 +108,30 @@ kdoprnt(void (*put)(int), const char *fmt, va_list ap)
put(ch);
}
lflag = 0;
-reswitch: switch (ch = *fmt++) {
+ zeropad = 0;
+ width = 0;
+rflag: ch = *fmt++;
+reswitch: switch (ch) {
+ case '0':
+ /*
+ * ``Note that 0 is taken as a flag, not as the
+ * beginning of a field width.''
+ * -- ANSI X3J11
+ */
+ zeropad = 1;
+ goto rflag;
+ case '1': case '2': case '3': case '4':
+ case '5': case '6': case '7': case '8': case '9':
+ n = 0;
+ do {
+ n = 10 * n + to_digit(ch);
+ ch = *fmt++;
+ } while (is_digit(ch));
+ width = n;
+ goto reswitch;
case 'l':
lflag++;
- goto reswitch;
+ goto rflag;
#ifndef STRIPPED
case 'b':
{
@@ -112,7 +139,7 @@ reswitch: switch (ch = *fmt++) {
ul = va_arg(ap, int);
p = va_arg(ap, char *);
- kprintn(put, ul, *p++);
+ kprintn(put, ul, *p++, width);
if (!ul)
break;
@@ -149,7 +176,7 @@ reswitch: switch (ch = *fmt++) {
put('-');
ull = -(int64_t)ull;
}
- kprintn64(put, ull, 10);
+ kprintn64(put, ull, 10, width);
break;
}
#endif
@@ -159,31 +186,31 @@ reswitch: switch (ch = *fmt++) {
put('-');
ul = -(long)ul;
}
- kprintn(put, ul, 10);
+ kprintn(put, ul, 10, width);
break;
case 'o':
#ifdef LIBSA_LONGLONG_PRINTF
if (lflag > 1) {
ull = va_arg(ap, u_int64_t);
- kprintn64(put, ull, 8);
+ kprintn64(put, ull, 8, width);
break;
}
#endif
ul = lflag ?
va_arg(ap, u_long) : va_arg(ap, u_int);
- kprintn(put, ul, 8);
+ kprintn(put, ul, 8, width);
break;
case 'u':
#ifdef LIBSA_LONGLONG_PRINTF
if (lflag > 1) {
ull = va_arg(ap, u_int64_t);
- kprintn64(put, ull, 10);
+ kprintn64(put, ull, 10, width);
break;
}
#endif
ul = lflag ?
va_arg(ap, u_long) : va_arg(ap, u_int);
- kprintn(put, ul, 10);
+ kprintn(put, ul, 10, width);
break;
case 'p':
put('0');
@@ -193,7 +220,7 @@ reswitch: switch (ch = *fmt++) {
#ifdef LIBSA_LONGLONG_PRINTF
if (lflag > 1) {
ull = va_arg(ap, u_int64_t);
- kprintn64(put, ull, 16);
+ kprintn64(put, ull, 16, width);
break;
}
#else
@@ -207,6 +234,10 @@ reswitch: switch (ch = *fmt++) {
do {
*p++ = hexdig[ull & 15];
} while (ull >>= 4);
+ while ((p - buf) < width &&
+ (p - buf) < sizeof(buf)) {
+ *p++ = '0';
+ }
do {
put(*--p);
} while (p > buf);
@@ -215,7 +246,7 @@ reswitch: switch (ch = *fmt++) {
#endif
ul = lflag ?
va_arg(ap, u_long) : va_arg(ap, u_int);
- kprintn(put, ul, 16);
+ kprintn(put, ul, 16, width);
break;
default:
put('%');
@@ -231,7 +262,7 @@ reswitch: switch (ch = *fmt++) {
}
void
-kprintn(void (*put)(int), unsigned long ul, int base)
+kprintn(void (*put)(int), unsigned long ul, int base, int width)
{
/* hold a long in base 8 */
char *p, buf[(sizeof(long) * NBBY / 3) + 1];
@@ -240,6 +271,9 @@ kprintn(void (*put)(int), unsigned long ul, int base)
do {
*p++ = hexdig[ul % base];
} while (ul /= base);
+ while ((p - buf) < width && (p - buf) < sizeof(buf)) {
+ *p++ = '0';
+ }
do {
put(*--p);
} while (p > buf);
@@ -247,7 +281,7 @@ kprintn(void (*put)(int), unsigned long ul, int base)
#ifdef LIBSA_LONGLONG_PRINTF
void
-kprintn64(void (*put)(int), u_int64_t ull, int base)
+kprintn64(void (*put)(int), u_int64_t ull, int base, int width)
{
/* hold an int64_t in base 8 */
char *p, buf[(sizeof(u_int64_t) * NBBY / 3) + 1];
@@ -256,6 +290,9 @@ kprintn64(void (*put)(int), u_int64_t ull, int base)
do {
*p++ = hexdig[ull % base];
} while (ull /= base);
+ while ((p - buf) < width && (p - buf) < sizeof(buf)) {
+ *p++ = '0';
+ }
do {
put(*--p);
} while (p > buf);
