From 019391bf852771070cb739900f9e20ae6c41c746 Mon Sep 17 00:00:00 2001 From: Vladimir Kondratyev Date: Mon, 5 Jul 2021 03:20:42 +0300 Subject: LinuxKPI: Implement strscpy strscpy copies the src string, or as much of it as fits, into the dst buffer. The dst buffer is always NUL terminated, unless it's zero-sized. strscpy returns the number of characters copied (not including the trailing NUL) or -E2BIG if len is 0 or src was truncated. Currently drm-kmod replaces strscpy with strncpy that is not quite correct as strncpy does not NUL-terminate truncated strings and returns different values on exit. Reviewed by: hselasky, imp, manu MFC after: 2 weeks Differential revision: https://reviews.freebsd.org/D31005 --- sys/compat/linuxkpi/common/include/linux/string.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'sys/compat/linuxkpi/common/include/linux') diff --git a/sys/compat/linuxkpi/common/include/linux/string.h b/sys/compat/linuxkpi/common/include/linux/string.h index 39201e203162..659a48d93596 100644 --- a/sys/compat/linuxkpi/common/include/linux/string.h +++ b/sys/compat/linuxkpi/common/include/linux/string.h @@ -167,4 +167,20 @@ str_has_prefix(const char *str, const char *prefix) return (strncmp(str, prefix, len) == 0 ? len : 0); } +static inline ssize_t +strscpy(char* dst, const char* src, size_t len) +{ + size_t i; + + if (len <= INT_MAX) { + for (i = 0; i < len; i++) + if ('\0' == (dst[i] = src[i])) + return ((ssize_t)i); + if (i != 0) + dst[--i] = '\0'; + } + + return (-E2BIG); +} + #endif /* _LINUX_STRING_H_ */ -- cgit v1.2.3