diff options
Diffstat (limited to 'tools/testing/selftests/bpf/bpf_util.h')
| -rw-r--r-- | tools/testing/selftests/bpf/bpf_util.h | 48 |
1 files changed, 35 insertions, 13 deletions
diff --git a/tools/testing/selftests/bpf/bpf_util.h b/tools/testing/selftests/bpf/bpf_util.h index 5f6963a320d7..6cb56501a505 100644 --- a/tools/testing/selftests/bpf/bpf_util.h +++ b/tools/testing/selftests/bpf/bpf_util.h @@ -8,6 +8,7 @@ #include <errno.h> #include <syscall.h> #include <bpf/libbpf.h> /* libbpf_num_possible_cpus */ +#include <linux/args.h> static inline unsigned int bpf_num_possible_cpus(void) { @@ -21,25 +22,43 @@ static inline unsigned int bpf_num_possible_cpus(void) return possible_cpus; } -/* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst - * is zero-terminated string no matter what (unless sz == 0, in which case - * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs - * in what is returned. Given this is internal helper, it's trivial to extend - * this, when necessary. Use this instead of strncpy inside libbpf source code. +/* + * Simplified strscpy() implementation. The kernel one is in lib/string.c */ -static inline void bpf_strlcpy(char *dst, const char *src, size_t sz) +static inline ssize_t sized_strscpy(char *dest, const char *src, size_t count) { - size_t i; + long res = 0; - if (sz == 0) - return; + if (count == 0) + return -E2BIG; - sz--; - for (i = 0; i < sz && src[i]; i++) - dst[i] = src[i]; - dst[i] = '\0'; + while (count > 1) { + char c; + + c = src[res]; + dest[res] = c; + if (!c) + return res; + res++; + count--; + } + + /* Force NUL-termination. */ + dest[res] = '\0'; + + /* Return E2BIG if the source didn't stop */ + return src[res] ? -E2BIG : res; } +#define __strscpy0(dst, src, ...) \ + sized_strscpy(dst, src, sizeof(dst)) +#define __strscpy1(dst, src, size) \ + sized_strscpy(dst, src, size) + +#undef strscpy /* Redefine the placeholder from tools/include/linux/string.h */ +#define strscpy(dst, src, ...) \ + CONCATENATE(__strscpy, COUNT_ARGS(__VA_ARGS__))(dst, src, __VA_ARGS__) + #define __bpf_percpu_val_align __attribute__((__aligned__(8))) #define BPF_DECLARE_PERCPU(type, name) \ @@ -67,6 +86,9 @@ static inline void bpf_strlcpy(char *dst, const char *src, size_t sz) #define sys_gettid() syscall(SYS_gettid) #endif +/* and poison usage to ensure it does not creep back in. */ +#pragma GCC poison gettid + #ifndef ENOTSUPP #define ENOTSUPP 524 #endif |