diff options
Diffstat (limited to 'strtonum.c')
-rw-r--r-- | strtonum.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/strtonum.c b/strtonum.c new file mode 100644 index 0000000..c54a47a --- /dev/null +++ b/strtonum.c @@ -0,0 +1,71 @@ +/* + * Copyright (c) 2004 Ted Unangst and Todd Miller + * All rights reserved. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#ifndef HAVE_STRTONUM + +long long +strtonum(const char *numstr, long long minval, long long maxval, + const char **errstrp); + +#include <errno.h> +#include <limits.h> +#include <stdlib.h> + +#define INVALID 1 +#define TOOSMALL 2 +#define TOOLARGE 3 + +long long +strtonum(const char *numstr, long long minval, long long maxval, + const char **errstrp) +{ + long long ll = 0; + int error = 0; + char *ep; + struct errval { + const char *errstr; + int err; + } ev[4] = { + { NULL, 0 }, + { "invalid", EINVAL }, + { "too small", ERANGE }, + { "too large", ERANGE }, + }; + + ev[0].err = errno; + errno = 0; + if (minval > maxval) { + error = INVALID; + } else { + ll = strtoll(numstr, &ep, 10); + if (numstr == ep || *ep != '\0') + error = INVALID; + else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval) + error = TOOSMALL; + else if ((ll == LLONG_MAX && errno == ERANGE) || ll > maxval) + error = TOOLARGE; + } + if (errstrp != NULL) + *errstrp = ev[error].errstr; + errno = ev[error].err; + if (error) + ll = 0; + + return (ll); +} + +#endif |