Update unaligned vs aligned ring buffer access comment

[lttng-ust.git] / include / usterr-signal-safe.h

diff --git a/include/usterr-signal-safe.h b/include/usterr-signal-safe.h
index a2e99dafdcef3777c08906c3315fcd5f64461383..6123c0b3a54bed820f36fbc74d93a1fed661646f 100644 (file)
--- a/include/usterr-signal-safe.h
+++ b/include/usterr-signal-safe.h
@@ -12,33 +12,40 @@
 #include <sys/types.h>
 #include <errno.h>
 #include <stdarg.h>
+#include <stdbool.h>
 #include <stdio.h>
-#include <share.h>
-#include "lttng/ust-tid.h"
-
-enum ust_loglevel {
-       UST_LOGLEVEL_UNKNOWN = 0,
-       UST_LOGLEVEL_NORMAL,
-       UST_LOGLEVEL_DEBUG,
+#include <ust-share.h>
+#include "ust-tid.h"
+#include "ust-snprintf.h"
+
+enum ust_err_loglevel {
+       UST_ERR_LOGLEVEL_UNKNOWN = 0,
+       UST_ERR_LOGLEVEL_NORMAL,
+       UST_ERR_LOGLEVEL_DEBUG,
 };
 
-extern volatile enum ust_loglevel ust_loglevel;
-void init_usterr(void);
+extern volatile enum ust_err_loglevel ust_err_loglevel
+       __attribute__((visibility("hidden")));
+
+void ust_err_init(void)
+       __attribute__((visibility("hidden")));
 
 #ifdef LTTNG_UST_DEBUG
-static inline int ust_debug(void)
+static inline bool ust_err_debug_enabled(void)
 {
-       return 1;
+       return true;
 }
 #else /* #ifdef LTTNG_UST_DEBUG */
-static inline int ust_debug(void)
+static inline bool ust_err_debug_enabled(void)
 {
-       return ust_loglevel == UST_LOGLEVEL_DEBUG;
+       return ust_err_loglevel == UST_ERR_LOGLEVEL_DEBUG;
 }
 #endif /* #else #ifdef LTTNG_UST_DEBUG */
 
+/*
+ * The default component for error messages.
+ */
 #ifndef UST_COMPONENT
-//#error UST_COMPONENT is undefined
 #define UST_COMPONENT libust
 #endif
 
@@ -46,27 +53,24 @@ static inline int ust_debug(void)
 #define UST_XSTR(d) UST_STR(d)
 #define UST_STR(s) #s
 
-#define USTERR_MAX_LEN 512
+#define UST_ERR_MAX_LEN        512
 
-/* We sometimes print in the tracing path, and tracing can occur in
+/*
+ * We sometimes print in the tracing path, and tracing can occur in
  * signal handlers, so we must use a print method which is signal safe.
  */
-
-extern int ust_safe_snprintf(char *str, size_t n, const char *fmt, ...)
-       __attribute__ ((format (printf, 3, 4)));
-
-/* Can't use dynamic allocation. Limit ourselves to USTERR_MAX_LEN chars. */
+/* Can't use dynamic allocation. Limit ourselves to UST_ERR_MAX_LEN chars. */
 /* Add end of string in case of buffer overflow. */
 #define sigsafe_print_err(fmt, args...)                                        \
 do {                                                                   \
-       if (ust_debug()) {                                              \
-               char ____buf[USTERR_MAX_LEN];                           \
+       if (ust_err_debug_enabled()) {                                  \
+               char ____buf[UST_ERR_MAX_LEN];                          \
                int ____saved_errno;                                    \
                                                                        \
                ____saved_errno = errno;        /* signal-safety */     \
                ust_safe_snprintf(____buf, sizeof(____buf), fmt, ## args); \
                ____buf[sizeof(____buf) - 1] = 0;                       \
-               patient_write(STDERR_FILENO, ____buf, strlen(____buf)); \
+               ust_patient_write(STDERR_FILENO, ____buf, strlen(____buf)); \
                errno = ____saved_errno;        /* signal-safety */     \
                fflush(stderr);                                         \
        }                                                               \
@@ -95,10 +99,12 @@ do {                                                                        \
  */
 #define PERROR(call, args...)                                          \
        do {                                                            \
-               if (ust_debug()) {                                      \
-                       char buf[200] = "Error in strerror_r()";        \
-                       strerror_r(errno, buf, sizeof(buf));            \
-                       ERRMSG("Error: " call ": %s", ## args, buf);    \
+               if (ust_err_debug_enabled()) {                          \
+                       char perror_buf[200] = "Error in strerror_r()"; \
+                       strerror_r(errno, perror_buf,                   \
+                                       sizeof(perror_buf));            \
+                       ERRMSG("Error: " call ": %s", ## args,          \
+                                       perror_buf);                    \
                }                                                       \
        } while(0)
 #else
@@ -107,11 +113,13 @@ do {                                                                      \
  */
 #define PERROR(call, args...)                                          \
        do {                                                            \
-               if (ust_debug()) {                                      \
-                       char *buf;                                      \
-                       char tmp[200];                                  \
-                       buf = strerror_r(errno, tmp, sizeof(tmp));      \
-                       ERRMSG("Error: " call ": %s", ## args, buf);    \
+               if (ust_err_debug_enabled()) {                          \
+                       char *perror_buf;                               \
+                       char perror_tmp[200];                           \
+                       perror_buf = strerror_r(errno, perror_tmp,      \
+                                       sizeof(perror_tmp));            \
+                       ERRMSG("Error: " call ": %s", ## args,          \
+                                       perror_buf);                    \
                }                                                       \
        } while(0)
 #endif