path: root/lib/cmdline.c
diff options
authorRobert P. J. Day <rpjday@crashcourse.ca>2008-07-25 01:45:31 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-25 10:53:27 -0700
commitfd193829744bc77392395cf8f47889235c97f0a3 (patch)
tree05e2612ee5d824cb679f4a236b14907b828b6888 /lib/cmdline.c
parentcb345d7352aa9e692ef4b83c41d3e6e1cdb2f846 (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>
Diffstat (limited to 'lib/cmdline.c')
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++;
+ if (retptr)
+ *retptr = endptr;
return ret;