diff options
| author | Robert P. J. Day <rpjday@crashcourse.ca> | 2008-07-25 01:45:31 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-07-25 10:53:27 -0700 |
| commit | fd193829744bc77392395cf8f47889235c97f0a3 (patch) | |
| tree | 05e2612ee5d824cb679f4a236b14907b828b6888 | |
| parent | cb345d7352aa9e692ef4b83c41d3e6e1cdb2f846 (diff) | |
lib: allow memparse() to accept a NULL and ignorable second parm
Extend memparse() to allow the caller to use a NULL second parameter, which
would represent no interest in returning the address of the end of the parsed
string.
In numerous cases, callers invoke memparse() to parse a possibly-suffixed
string (such as "64K" or "2G" or whatever) and define a character pointer to
accept the end pointer being returned by memparse() even though they have no
interest in it and promptly throw it away.
This (backward-compatible) enhancement allows callers to use NULL in the cases
where they just don't care about getting back that end pointer.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | lib/cmdline.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/lib/cmdline.c b/lib/cmdline.c index f596c08d213..5ba8a942a47 100644 --- a/lib/cmdline.c +++ b/lib/cmdline.c @@ -116,7 +116,7 @@ char *get_options(const char *str, int nints, int *ints) /** * memparse - parse a string with mem suffixes into a number * @ptr: Where parse begins - * @retptr: (output) Pointer to next char after parse completes + * @retptr: (output) Optional pointer to next char after parse completes * * Parses a string into a number. The number stored at @ptr is * potentially suffixed with %K (for kilobytes, or 1024 bytes), @@ -126,11 +126,13 @@ char *get_options(const char *str, int nints, int *ints) * megabyte, or one gigabyte, respectively. */ -unsigned long long memparse (char *ptr, char **retptr) +unsigned long long memparse(char *ptr, char **retptr) { - unsigned long long ret = simple_strtoull (ptr, retptr, 0); + char *endptr; /* local pointer to end of parsed string */ - switch (**retptr) { + unsigned long long ret = simple_strtoull(ptr, &endptr, 0); + + switch (*endptr) { case 'G': case 'g': ret <<= 10; @@ -140,10 +142,14 @@ unsigned long long memparse (char *ptr, char **retptr) case 'K': case 'k': ret <<= 10; - (*retptr)++; + endptr++; default: break; } + + if (retptr) + *retptr = endptr; + return ret; } |