| 1 | /* |
| 2 | * SPDX-License-Identifier: MIT |
| 3 | * |
| 4 | * Copyright (C) 2013-2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 5 | * Copyright (C) 2021 Norbert Lange <nolange79@gmail.com> |
| 6 | * |
| 7 | * Shared helper macro for tracelog and tracef. |
| 8 | */ |
| 9 | |
| 10 | #define LTTNG_UST_TRACELOG_VARARG(fmt, callback, ...) \ |
| 11 | do { \ |
| 12 | char local_buf[LTTNG_TRACE_PRINTF_BUFSIZE]; \ |
| 13 | char *alloc_buff = NULL, *msg = local_buf; \ |
| 14 | size_t len = 0; \ |
| 15 | va_list ap; \ |
| 16 | \ |
| 17 | if (caa_unlikely(fmt[0] == '%' && fmt[1] == 's' && fmt[2] == '\0')) { \ |
| 18 | va_start(ap, fmt); \ |
| 19 | msg = va_arg(ap, char *); \ |
| 20 | va_end(ap); \ |
| 21 | len = strlen(msg); \ |
| 22 | } else { \ |
| 23 | size_t buflen = sizeof(local_buf); \ |
| 24 | int ret; \ |
| 25 | \ |
| 26 | /* On-stack buffer attempt */ \ |
| 27 | va_start(ap, fmt); \ |
| 28 | ret = vsnprintf(msg, buflen, fmt, ap); \ |
| 29 | va_end(ap); \ |
| 30 | if (caa_unlikely(ret < 0)) \ |
| 31 | break; \ |
| 32 | len = (size_t)ret; \ |
| 33 | \ |
| 34 | if (caa_unlikely(len >= sizeof(local_buf))) { \ |
| 35 | buflen = len + 1; \ |
| 36 | alloc_buff = (char *)malloc(buflen); \ |
| 37 | if (!alloc_buff) \ |
| 38 | goto end; \ |
| 39 | msg = alloc_buff; \ |
| 40 | va_start(ap, fmt); \ |
| 41 | ret = vsnprintf(msg, buflen, fmt, ap); \ |
| 42 | va_end(ap); \ |
| 43 | lttng_ust_runtime_bug_on(ret < 0 || (size_t)ret != buflen - 1); \ |
| 44 | len = (size_t)ret; \ |
| 45 | } \ |
| 46 | } \ |
| 47 | \ |
| 48 | callback(__VA_ARGS__); \ |
| 49 | end: \ |
| 50 | /* Don't call a potentially instrumented forbidden free needlessly. */ \ |
| 51 | if (caa_unlikely(alloc_buff)) \ |
| 52 | free(alloc_buff); \ |
| 53 | } while(0) |
| 54 | |
| 55 | #define LTTNG_UST_TRACELOG_VALIST(fmt, ap, callback, ...) \ |
| 56 | do { \ |
| 57 | char local_buf[LTTNG_TRACE_PRINTF_BUFSIZE]; \ |
| 58 | char *alloc_buff = NULL, *msg = local_buf; \ |
| 59 | size_t len = 0; \ |
| 60 | \ |
| 61 | if (caa_unlikely(fmt[0] == '%' && fmt[1] == 's' && fmt[2] == '\0')) { \ |
| 62 | msg = va_arg(ap, char *); \ |
| 63 | len = strlen(msg); \ |
| 64 | } else { \ |
| 65 | size_t buflen = sizeof(local_buf); \ |
| 66 | va_list ap2; \ |
| 67 | int ret; \ |
| 68 | \ |
| 69 | va_copy(ap2, ap); \ |
| 70 | ret = vsnprintf(msg, buflen, fmt, ap2); \ |
| 71 | va_end(ap2); \ |
| 72 | if (caa_unlikely(ret < 0)) \ |
| 73 | break; \ |
| 74 | len = (size_t)ret; \ |
| 75 | \ |
| 76 | if (caa_unlikely(len >= sizeof(local_buf))) { \ |
| 77 | buflen = len + 1; \ |
| 78 | alloc_buff = (char *)malloc(buflen); \ |
| 79 | if (!alloc_buff) \ |
| 80 | goto end; \ |
| 81 | msg = alloc_buff; \ |
| 82 | ret = vsnprintf(msg, buflen, fmt, ap); \ |
| 83 | lttng_ust_runtime_bug_on(ret < 0 || (size_t)ret != buflen - 1); \ |
| 84 | len = (size_t)ret; \ |
| 85 | } \ |
| 86 | } \ |
| 87 | \ |
| 88 | callback(__VA_ARGS__); \ |
| 89 | end: \ |
| 90 | /* Don't call a potentially instrumented forbidden free needlessly. */ \ |
| 91 | if (caa_unlikely(alloc_buff)) \ |
| 92 | free(alloc_buff); \ |
| 93 | } while (0) |