diff --git a/src/utils/common.c b/src/utils/common.c index 26c401c70..64f476df4 100644 --- a/src/utils/common.c +++ b/src/utils/common.c @@ -183,6 +183,35 @@ void wpa_get_ntp_timestamp(u8 *buf) os_memcpy(buf + 4, (u8 *) &tmp, 4); } +/** + * wpa_scnprintf - Simpler-to-use snprintf function + * @buf: Output buffer + * @size: Buffer size + * @fmt: format + * + * Simpler snprintf version that doesn't require further error checks - the + * return value only indicates how many bytes were actually written, excluding + * the NULL byte (i.e., 0 on error, size-1 if buffer is not big enough). + */ +int wpa_scnprintf(char *buf, size_t size, const char *fmt, ...) +{ + va_list ap; + int ret; + + if (!size) + return 0; + + va_start(ap, fmt); + ret = vsnprintf(buf, size, fmt, ap); + va_end(ap); + + if (ret < 0) + return 0; + if ((size_t) ret >= size) + return size - 1; + + return ret; +} static inline int _wpa_snprintf_hex(char *buf, size_t buf_size, const u8 *data, size_t len, int uppercase) diff --git a/src/utils/common.h b/src/utils/common.h index 284e7e5cf..70d76a935 100644 --- a/src/utils/common.h +++ b/src/utils/common.h @@ -477,6 +477,7 @@ int hex2byte(const char *hex); int hexstr2bin(const char *hex, u8 *buf, size_t len); void inc_byte_array(u8 *counter, size_t len); void wpa_get_ntp_timestamp(u8 *buf); +int wpa_scnprintf(char *buf, size_t size, const char *fmt, ...); int wpa_snprintf_hex(char *buf, size_t buf_size, const u8 *data, size_t len); int wpa_snprintf_hex_uppercase(char *buf, size_t buf_size, const u8 *data, size_t len);