[PATCH v2 1/2] lib/vsprintf: refactor duplicate code to special_hex_number()

From: Andy Shevchenko
Date: Tue Dec 29 2015 - 11:43:01 EST


special_hex_number() is a helper to print a fixed size type in a hex format
with '0x' prefix, zero padding, and small letters. In the module we have
already several copies of such code. Consolidate them under
special_hex_number() helper.

There are couple of differences though.

It seems nobody cared about the output in case of CONFIG_KALLSYMS=n, when
printing symbol address, because the asked field width is not enough to care
last 2 characters in the string represantation of the pointer. Fixed here.

The %pNF specifier used to be allowed with a specific field width, though there
is neither any user of it nor mention the possibility in the documentation.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
lib/vsprintf.c | 53 +++++++++++++++++++++++++++--------------------------
1 file changed, 27 insertions(+), 26 deletions(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 88ed574..6946431 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -514,6 +514,20 @@ char *number(char *buf, char *end, unsigned long long num,
return buf;
}

+static noinline_for_stack
+char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
+{
+ struct printf_spec spec;
+
+ spec.type = FORMAT_TYPE_PTR;
+ spec.field_width = 2 + 2 * size; /* 0x + hex */
+ spec.flags = SPECIAL | SMALL | ZEROPAD;
+ spec.base = 16;
+ spec.precision = -1;
+
+ return number(buf, end, num, spec);
+}
+
static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
{
size_t size;
@@ -649,11 +663,7 @@ char *symbol_string(char *buf, char *end, void *ptr,

return string(buf, end, sym, spec);
#else
- spec.field_width = 2 * sizeof(void *);
- spec.flags |= SPECIAL | SMALL | ZEROPAD;
- spec.base = 16;
-
- return number(buf, end, value, spec);
+ return special_hex_number(buf, end, value, sizeof(void *));
#endif
}

@@ -1315,39 +1325,33 @@ char *uuid_string(char *buf, char *end, const u8 *addr,
}

static
-char *netdev_feature_string(char *buf, char *end, const u8 *addr,
- struct printf_spec spec)
+char *netdev_feature_string(char *buf, char *end, const void *addr)
{
- spec.flags |= SPECIAL | SMALL | ZEROPAD;
- if (spec.field_width == -1)
- spec.field_width = 2 + 2 * sizeof(netdev_features_t);
- spec.base = 16;
+ unsigned long long num = *(const netdev_features_t *)addr;
+ int size = sizeof(netdev_features_t);

- return number(buf, end, *(const netdev_features_t *)addr, spec);
+ return special_hex_number(buf, end, num, size);
}

static noinline_for_stack
-char *address_val(char *buf, char *end, const void *addr,
- struct printf_spec spec, const char *fmt)
+char *address_val(char *buf, char *end, const void *addr, const char *fmt)
{
unsigned long long num;
-
- spec.flags |= SPECIAL | SMALL | ZEROPAD;
- spec.base = 16;
+ int size;

switch (fmt[1]) {
case 'd':
num = *(const dma_addr_t *)addr;
- spec.field_width = sizeof(dma_addr_t) * 2 + 2;
+ size = sizeof(dma_addr_t);
break;
case 'p':
default:
num = *(const phys_addr_t *)addr;
- spec.field_width = sizeof(phys_addr_t) * 2 + 2;
+ size = sizeof(phys_addr_t);
break;
}

- return number(buf, end, num, spec);
+ return special_hex_number(buf, end, num, size);
}

static noinline_for_stack
@@ -1366,10 +1370,7 @@ char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
#ifdef CONFIG_COMMON_CLK
return string(buf, end, __clk_get_name(clk), spec);
#else
- spec.base = 16;
- spec.field_width = sizeof(unsigned long) * 2 + 2;
- spec.flags |= SPECIAL | SMALL | ZEROPAD;
- return number(buf, end, (unsigned long)clk, spec);
+ return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
#endif
}
}
@@ -1672,11 +1673,11 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
case 'N':
switch (fmt[1]) {
case 'F':
- return netdev_feature_string(buf, end, ptr, spec);
+ return netdev_feature_string(buf, end, ptr);
}
break;
case 'a':
- return address_val(buf, end, ptr, spec, fmt);
+ return address_val(buf, end, ptr, fmt);
case 'd':
return dentry_name(buf, end, ptr, spec, fmt);
case 'C':
--
2.6.4

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