cutils: unsigned int parsing functions

There are lots of duplicate parsing code using strto*() in QEMU, and
most of that code is broken in one way or another. Even the visitors
code have duplicate integer parsing code[1]. This introduces functions
to help parsing unsigned int values: parse_uint() and parse_uint_full().

Parsing functions for signed ints and floats will be submitted later.

parse_uint_full() has all the checks made by opts_type_uint64() at
opts-visitor.c:

 - Check for NULL (returns -EINVAL)
 - Check for negative numbers (returns -EINVAL)
 - Check for empty string (returns -EINVAL)
 - Check for overflow or other errno values set by strtoll() (returns
   -errno)
 - Check for end of string (reject invalid characters after number)
   (returns -EINVAL)

parse_uint() does everything above except checking for the end of the
string, so callers can continue parsing the remainder of string after
the number.

Unit tests included.

[1] string-input-visitor.c:parse_int() could use the same parsing code
    used by opts-visitor.c:opts_type_int(), instead of duplicating that
    logic.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit is contained in:
Eduardo Habkost 2013-02-04 16:27:45 -02:00 committed by Anthony Liguori
parent ff057ccb07
commit e3f9fe2d40
4 changed files with 357 additions and 0 deletions

View file

@ -173,6 +173,10 @@ int qemu_fdatasync(int fd);
int fcntl_setfl(int fd, int flag);
int qemu_parse_fd(const char *param);
int parse_uint(const char *s, unsigned long long *value, char **endptr,
int base);
int parse_uint_full(const char *s, unsigned long long *value, int base);
/*
* strtosz() suffixes used to specify the default treatment of an
* argument passed to strtosz() without an explicit suffix.