btrfs-progs: Improve the parse_size() error message

When using parse_size(), even non-numeric value is passed, it will only
give error message "ERROR: size value is empty", which is quite
confusing for end users.

This patch will introduce more meaningful error message for the
following new cases
1) Invalid size string (non-numeric string)
2) Minus size value (like "-1K")

Also this patch will take full use of endptr returned by strtoll() to
reduce unneeded loop.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
This commit is contained in:
Qu Wenruo 2014-06-13 10:55:57 +08:00 committed by David Sterba
parent 4da2751451
commit 445a3a0a51

70
utils.c
View File

@ -1638,20 +1638,57 @@ scan_again:
return 0; return 0;
} }
u64 parse_size(char *s) /*
* A not-so-good version fls64. No fascinating optimization since
* no one except parse_size use it
*/
static int fls64(u64 x)
{ {
int i; int i;
for (i = 0; i <64; i++)
if (x << i & (1UL << 63))
return 64 - i;
return 64 - i;
}
u64 parse_size(char *s)
{
char c; char c;
char *endptr;
u64 mult = 1; u64 mult = 1;
u64 ret;
for (i = 0; s && s[i] && isdigit(s[i]); i++) ; if (!s) {
if (!i) { fprintf(stderr, "ERROR: Size value is empty\n");
fprintf(stderr, "ERROR: size value is empty\n"); exit(1);
exit(50);
} }
if (s[0] == '-') {
if (s[i]) { fprintf(stderr,
c = tolower(s[i]); "ERROR: Size value '%s' is less equal than 0\n", s);
exit(1);
}
ret = strtoull(s, &endptr, 10);
if (endptr == s) {
fprintf(stderr, "ERROR: Size value '%s' is invalid\n", s);
exit(1);
}
if (endptr[0] && endptr[1]) {
fprintf(stderr, "ERROR: Illegal suffix contains character '%c' in wrong position\n",
endptr[1]);
exit(1);
}
/*
* strtoll returns LLONG_MAX when overflow, if this happens,
* need to call strtoull to get the real size
*/
if (errno == ERANGE && ret == ULLONG_MAX) {
fprintf(stderr,
"ERROR: Size value '%s' is too large for u64\n", s);
exit(1);
}
if (endptr[0]) {
c = tolower(endptr[0]);
switch (c) { switch (c) {
case 'e': case 'e':
mult *= 1024; mult *= 1024;
@ -1674,18 +1711,19 @@ u64 parse_size(char *s)
case 'b': case 'b':
break; break;
default: default:
fprintf(stderr, "ERROR: Unknown size descriptor " fprintf(stderr, "ERROR: Unknown size descriptor '%c'\n",
"'%c'\n", c); c);
exit(1); exit(1);
} }
} }
if (s[i] && s[i+1]) { /* Check whether ret * mult overflow */
fprintf(stderr, "ERROR: Illegal suffix contains " if (fls64(ret) + fls64(mult) - 1 > 64) {
"character '%c' in wrong position\n", fprintf(stderr,
s[i+1]); "ERROR: Size value '%s' is too large for u64\n", s);
exit(51); exit(1);
} }
return strtoull(s, NULL, 10) * mult; ret *= mult;
return ret;
} }
int open_file_or_dir3(const char *fname, DIR **dirstream, int open_flags) int open_file_or_dir3(const char *fname, DIR **dirstream, int open_flags)