On Mon, 2016-02-22 at 16:24 -0500, Jessica Yu wrote: > Implement basic character sets for the '%[]' conversion specifier. > > The '%[]' conversion specifier matches a nonempty sequence of > characters > from the specified set of accepted (or with '^', rejected) characters > between the brackets. The substring matched is to be made up of > characters > in (or not in) the set. This implementation differs from its glibc > counterpart in that it does not support character ranges (e.g., 'a-z' > or > '0-9'), the hyphen '-' is *not* a special character, and the brackets > themselves cannot be matched. > > Signed-off-by: Jessica Yu <[email protected]> > --- > Patch based on linux-next-20160222. > > v2: > - Use kstrndup() to copy the character set from fmt instead of using > a > statically allocated array > > lib/vsprintf.c | 39 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 39 insertions(+) > > diff --git a/lib/vsprintf.c b/lib/vsprintf.c > index 525c8e1..93a6f52 100644 > --- a/lib/vsprintf.c > +++ b/lib/vsprintf.c > @@ -2714,6 +2714,45 @@ int vsscanf(const char *buf, const char *fmt, > va_list args) > num++; > } > continue; > + case '[': > + { > + char *s = (char *)va_arg(args, char *); > + char *set; > + size_t (*op)(const char *str, const char > *set); > + size_t len = 0; > + bool negate = (*(fmt) == '^'); > + > + if (field_width == -1) > + field_width = SHRT_MAX;
I'm not sure if it's needed here. It will count down till 0 in any case. > + > + op = negate ? &strcspn : &strspn; > + if (negate) > + fmt++; > + > + len = strcspn(fmt, "]"); > + /* invalid format; stop here */ > + if (!len) > + return num; > + > + set = kstrndup(fmt, len, GFP_KERNEL); > + if (!set) > + return num; > + > + /* advance fmt past ']' */ > + fmt += len + 1; > + > + len = (*op)(str, set); Can we use just normal form: op(); ? > + /* no matches */ > + if (!len) Memory leak here. > + return num; > + > + while (*str && len-- && field_width--) > + *s++ = *str++; Looks like strcpy() variant. First of all, is it possible to have *str == '\0' when len != 0? > + *s = '\0'; > + kfree(set); > + num++; > + } > + continue; > case 'o': > base = 8; > break; -- Andy Shevchenko <[email protected]> Intel Finland Oy
