From: Dmitry Safonov 0x7f454c46@gmail.com
Instead of pre-allocating a fixed-sized buffer of TEST_MSG_BUFFER_SIZE and printing into it, call vsnprintf() with str = NULL, which will return the needed size of the buffer. This hack is documented in man 3 vsnprintf.
Essentially, in C++ terms, it re-invents std::stringstream, which is going to be used to print different tracing paths and formatted strings. Use it straight away in __test_print() - which is thread-safe version of printing in selftests.
Signed-off-by: Dmitry Safonov 0x7f454c46@gmail.com --- tools/testing/selftests/net/tcp_ao/lib/aolib.h | 59 ++++++++++++++++++++++---- 1 file changed, 50 insertions(+), 9 deletions(-)
diff --git a/tools/testing/selftests/net/tcp_ao/lib/aolib.h b/tools/testing/selftests/net/tcp_ao/lib/aolib.h index fbc7f6111815..60a63419cabb 100644 --- a/tools/testing/selftests/net/tcp_ao/lib/aolib.h +++ b/tools/testing/selftests/net/tcp_ao/lib/aolib.h @@ -37,17 +37,58 @@ extern void __test_xfail(const char *buf); extern void __test_error(const char *buf); extern void __test_skip(const char *buf);
-__attribute__((__format__(__printf__, 2, 3))) -static inline void __test_print(void (*fn)(const char *), const char *fmt, ...) +static inline char *test_snprintf(const char *fmt, va_list vargs) { -#define TEST_MSG_BUFFER_SIZE 4096 - char buf[TEST_MSG_BUFFER_SIZE]; - va_list arg; + char *ret = NULL; + size_t size = 0; + va_list tmp; + int n = 0;
- va_start(arg, fmt); - vsnprintf(buf, sizeof(buf), fmt, arg); - va_end(arg); - fn(buf); + va_copy(tmp, vargs); + n = vsnprintf(ret, size, fmt, tmp); + if (n < 0) + return NULL; + + size = (size_t) n + 1; + ret = malloc(size); + if (ret == NULL) + return NULL; + + n = vsnprintf(ret, size, fmt, vargs); + if (n < 0 || n > size - 1) { + free(ret); + return NULL; + } + return ret; +} + +static __printf(1, 2) inline char *test_sprintf(const char *fmt, ...) +{ + va_list vargs; + char *ret; + + va_start(vargs, fmt); + ret = test_snprintf(fmt, vargs); + va_end(vargs); + + return ret; +} + +static __printf(2, 3) inline void __test_print(void (*fn)(const char *), + const char *fmt, ...) +{ + va_list vargs; + char *msg; + + va_start(vargs, fmt); + msg = test_snprintf(fmt, vargs); + va_end(vargs); + + if (!msg) + return; + + fn(msg); + free(msg); }
#define test_print(fmt, ...) \