MINOR: debug: use bit fields for the debug type and fatality

Till now the BUG_ON() series of macros has been relying on magic values
0,1,2, and 3 passed down the chain to decide whether to log a bug or a
warning, and whether to crash or just warn. But this doesn't capture the
whole usage and is causing difficulties because we also have type "check",
and these values are passed to variables historically named "crash" or
"taint" suggesting booleans while bit-exact checks have to be done.

Let's replace them with a combination that separately indicates:
  - the type (check, warning, bug, abort), one bit per type, expected
    to be exclusive
  - type fatality (warning or fatal), one bit per level, must be
    exclusive as well

This allows us to easily replace the checks and map the numbers to their
equivalent definitions. The macros are called DBG_DET_* (debug details),
and the "crash" and "taint" fields have been renamed "details" as well.

For now this is the exact equivalent of what we previously had.

diff --git a/include/haproxy/bug.h b/include/haproxy/bug.h
index c61693800943b355330038ca0d2c8dad13860440..d9cb907e8c0f3c0894e1fdc981ae046a6e34b238 100644 (file)
--- a/include/haproxy/bug.h
+++ b/include/haproxy/bug.h
@@ -168,7 +168,7 @@ struct debug_count {
 #endif
 
 /* report a bug on stderr */
-void complain(int *counter, const char *msg, int taint);
+void complain(int *counter, const char *msg, uint details);
 void ha_backtrace_to_stderr(int hint);
 
 /* Let's make DEBUG_STRESS equal to zero if not set or not valid, or to
@@ -234,6 +234,27 @@ static inline __attribute((always_inline,noreturn,unused)) void ha_crash_now(voi
 #endif // end of arch-specific ha_crash_now() definitions
 
 
+/* details of a debug event passed to _BUG_ON*(), allows to distinguish some
+ * causes (check, warn, bug, abort) and the fatality (none, warning, fatal).
+ * These are bit fields that can be ORed.
+ */
+#define DBG_DET_NONE            0x00000000
+#define DBG_DET_TYP_CHK         0x00000001
+#define DBG_DET_TYP_WRN         0x00000002
+#define DBG_DET_TYP_BUG         0x00000004
+#define DBG_DET_TYP_ABT         0x00000008
+#define DBG_DET_FAT_WARN        0x00000010
+#define DBG_DET_FAT_FATL        0x00000020
+// combinations
+#define DBG_WARN_CHK            (DBG_DET_FAT_WARN | DBG_DET_TYP_CHK)
+#define DBG_WARN_WRN            (DBG_DET_FAT_WARN | DBG_DET_TYP_WRN)
+#define DBG_WARN_BUG            (DBG_DET_FAT_WARN | DBG_DET_TYP_BUG)
+#define DBG_WARN_ABT            (DBG_DET_FAT_WARN | DBG_DET_TYP_ABT)
+#define DBG_FATL_CHK            (DBG_DET_FAT_FATL | DBG_DET_TYP_CHK)
+#define DBG_FATL_WRN            (DBG_DET_FAT_FATL | DBG_DET_TYP_WRN)
+#define DBG_FATL_BUG            (DBG_DET_FAT_FATL | DBG_DET_TYP_BUG)
+#define DBG_FATL_ABT            (DBG_DET_FAT_FATL | DBG_DET_TYP_ABT)
+
 /* ABORT_NOW() usually takes no argument and will cause the program to abort
  * exactly where it is. We prefer to emit an invalid instruction to preserve
  * all registers, but it may fall back to a regular abort depending on the
@@ -280,7 +301,7 @@ static __attribute__((noinline,noreturn,unused)) void abort_with_line(uint line)
 
 #define __ABORT_NOW(file, line, ...) do {                              \
                if (sizeof("" __VA_ARGS__) > 1)                         \
-                       complain(NULL, "\nABORT at " file ":" #line ": " __VA_ARGS__ "\n", 1); \
+                       complain(NULL, "\nABORT at " file ":" #line ": " __VA_ARGS__ "\n", DBG_FATL_ABT); \
                ha_backtrace_to_stderr(1);                              \
                abort_with_line(__LINE__);                              \
        } while (0)
@@ -373,28 +394,28 @@ extern __attribute__((__weak__)) struct debug_count __stop_dbg_cnt  HA_SECTION_S
 /* This is the generic low-level macro dealing with conditional warnings and
  * bugs. The caller decides whether to crash or not and what prefix and suffix
  * to pass. The macro returns the boolean value of the condition as an int for
- * the case where it wouldn't die. The <crash> flag is made of:
- *  - crash & 1: crash yes/no;
- *  - crash & 2: taint as bug instead of warn
+ * the case where it wouldn't die. The <details> flag is made of:
+ *  - details & DBG_DET_FAT_FATL: crash yes/no;
+ *  - details & DBG_DET_TYP_BUG: taint as bug instead of warn
  * The optional argument must be a single constant string that will be appended
  * on a second line after the condition message, to give a bit more context
  * about the problem.
  */
-#define _BUG_ON(cond, file, line, crash, pfx, sfx, ...)                                \
+#define _BUG_ON(cond, file, line, details, pfx, sfx, ...)                      \
        (void)(unlikely(cond) ? ({                                              \
                __DBG_COUNT(cond, file, line, DBG_BUG, __VA_ARGS__);            \
-               __BUG_ON(cond, file, line, crash, pfx, sfx, __VA_ARGS__);       \
+               __BUG_ON(cond, file, line, details, pfx, sfx, __VA_ARGS__);     \
                1; /* let's return the true condition */                        \
        }) : 0)
 
-#define __BUG_ON(cond, file, line, crash, pfx, sfx, ...) do {          \
+#define __BUG_ON(cond, file, line, details, pfx, sfx, ...) do {                \
                const char *msg;                                        \
                if (sizeof("" __VA_ARGS__) > 1)                         \
                        msg ="\n" pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx "\n" __VA_ARGS__ "\n"; \
                else                                                    \
                        msg = "\n" pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx "\n"; \
-               complain(NULL, msg, crash);                             \
-               if (crash & 1)                                          \
+               complain(NULL, msg, details);                           \
+               if (details & DBG_DET_FAT_FATL)                         \
                        ABORT_NOW();                                    \
                else                                                    \
                        ha_backtrace_to_stderr(0);                      \
@@ -405,14 +426,14 @@ extern __attribute__((__weak__)) struct debug_count __stop_dbg_cnt  HA_SECTION_S
  * certain unexpected conditions in field. Later on, in cores it will be
  * possible to verify these counters.
  */
-#define _BUG_ON_ONCE(cond, file, line, crash, pfx, sfx, ...)                   \
+#define _BUG_ON_ONCE(cond, file, line, details, pfx, sfx, ...)                 \
        (void)(unlikely(cond) ? ({                                              \
                __DBG_COUNT(cond, file, line, DBG_BUG_ONCE, __VA_ARGS__);       \
-               __BUG_ON_ONCE(cond, file, line, crash, pfx, sfx, __VA_ARGS__);  \
+               __BUG_ON_ONCE(cond, file, line, details, pfx, sfx, __VA_ARGS__);\
                1; /* let's return the true condition */                        \
        }) : 0)
 
-#define __BUG_ON_ONCE(cond, file, line, crash, pfx, sfx, ...) do {     \
+#define __BUG_ON_ONCE(cond, file, line, details, pfx, sfx, ...) do {   \
                static int __match_count_##line;                        \
                const char *msg;                                        \
                if (sizeof("" __VA_ARGS__) > 1)                         \
@@ -421,8 +442,8 @@ extern __attribute__((__weak__)) struct debug_count __stop_dbg_cnt  HA_SECTION_S
                        msg = "\n" pfx "condition \"" #cond "\" matched at " file ":" #line "" sfx "\n"; \
                if (_HA_ATOMIC_FETCH_ADD(&__match_count_##line, 1))     \
                        break;                                          \
-               complain(NULL, msg, crash);                             \
-               if (crash & 1)                                          \
+               complain(NULL, msg, details);                           \
+               if (details & DBG_DET_FAT_FATL)                         \
                        ABORT_NOW();                                    \
                else                                                    \
                        ha_backtrace_to_stderr(0);                      \
@@ -444,27 +465,27 @@ extern __attribute__((__weak__)) struct debug_count __stop_dbg_cnt  HA_SECTION_S
 #if defined(DEBUG_STRICT) && (DEBUG_STRICT > 0)
 # if defined(DEBUG_STRICT_ACTION) && (DEBUG_STRICT_ACTION < 1)
 /* Lowest level: BUG_ON() warns, WARN_ON() warns, CHECK_IF() warns */
-#  define BUG_ON(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, 2, "WARNING: bug ",   " (not crashing but process is untrusted now, please report to developers)", __VA_ARGS__)
-#  define WARN_ON(cond, ...)  _BUG_ON     (cond, __FILE__, __LINE__, 0, "WARNING: warn ",  " (please report to developers)", __VA_ARGS__)
-#  define CHECK_IF(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, 0, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
+#  define BUG_ON(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, DBG_WARN_BUG, "WARNING: bug ",   " (not crashing but process is untrusted now, please report to developers)", __VA_ARGS__)
+#  define WARN_ON(cond, ...)  _BUG_ON     (cond, __FILE__, __LINE__, DBG_WARN_WRN, "WARNING: warn ",  " (please report to developers)", __VA_ARGS__)
+#  define CHECK_IF(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, DBG_WARN_CHK, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
 #  define COUNT_IF(cond, ...) _COUNT_IF   (cond, __FILE__, __LINE__, __VA_ARGS__)
 # elif !defined(DEBUG_STRICT_ACTION) || (DEBUG_STRICT_ACTION == 1)
 /* default level: BUG_ON() crashes, WARN_ON() warns, CHECK_IF() warns */
-#  define BUG_ON(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, 3, "FATAL: bug ",     "", __VA_ARGS__)
-#  define WARN_ON(cond, ...)  _BUG_ON     (cond, __FILE__, __LINE__, 0, "WARNING: warn ",  " (please report to developers)", __VA_ARGS__)
-#  define CHECK_IF(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, 0, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
+#  define BUG_ON(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, DBG_FATL_BUG, "FATAL: bug ",     "", __VA_ARGS__)
+#  define WARN_ON(cond, ...)  _BUG_ON     (cond, __FILE__, __LINE__, DBG_WARN_WRN, "WARNING: warn ",  " (please report to developers)", __VA_ARGS__)
+#  define CHECK_IF(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, DBG_WARN_CHK, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
 #  define COUNT_IF(cond, ...) _COUNT_IF   (cond, __FILE__, __LINE__, __VA_ARGS__)
 # elif defined(DEBUG_STRICT_ACTION) && (DEBUG_STRICT_ACTION == 2)
 /* Stricter level: BUG_ON() crashes, WARN_ON() crashes, CHECK_IF() warns */
-#  define BUG_ON(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, 3, "FATAL: bug ",     "", __VA_ARGS__)
-#  define WARN_ON(cond, ...)  _BUG_ON     (cond, __FILE__, __LINE__, 1, "FATAL: warn ",    "", __VA_ARGS__)
-#  define CHECK_IF(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, 0, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
+#  define BUG_ON(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, DBG_FATL_BUG, "FATAL: bug ",     "", __VA_ARGS__)
+#  define WARN_ON(cond, ...)  _BUG_ON     (cond, __FILE__, __LINE__, DBG_FATL_WRN, "FATAL: warn ",    "", __VA_ARGS__)
+#  define CHECK_IF(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, DBG_WARN_CHK, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
 #  define COUNT_IF(cond, ...) _COUNT_IF   (cond, __FILE__, __LINE__, __VA_ARGS__)
 # elif defined(DEBUG_STRICT_ACTION) && (DEBUG_STRICT_ACTION >= 3)
 /* Developer/CI level: BUG_ON() crashes, WARN_ON() crashes, CHECK_IF() crashes */
-#  define BUG_ON(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, 3, "FATAL: bug ",     "", __VA_ARGS__)
-#  define WARN_ON(cond, ...)  _BUG_ON     (cond, __FILE__, __LINE__, 1, "FATAL: warn ",    "", __VA_ARGS__)
-#  define CHECK_IF(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, 1, "FATAL: check ",   "", __VA_ARGS__)
+#  define BUG_ON(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, DBG_FATL_BUG, "FATAL: bug ",     "", __VA_ARGS__)
+#  define WARN_ON(cond, ...)  _BUG_ON     (cond, __FILE__, __LINE__, DBG_FATL_WRN, "FATAL: warn ",    "", __VA_ARGS__)
+#  define CHECK_IF(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, DBG_FATL_CHK, "FATAL: check ",   "", __VA_ARGS__)
 #  define COUNT_IF(cond, ...) _COUNT_IF   (cond, __FILE__, __LINE__, __VA_ARGS__)
 # endif
 #else /* DEBUG_STRICT not defined below */
@@ -487,18 +508,18 @@ extern __attribute__((__weak__)) struct debug_count __stop_dbg_cnt  HA_SECTION_S
 #if defined(DEBUG_STRICT) && (DEBUG_STRICT > 1)
 # if defined(DEBUG_STRICT_ACTION) && (DEBUG_STRICT_ACTION < 1)
 /* Lowest level: BUG_ON() warns, CHECK_IF() warns */
-#  define BUG_ON_HOT(cond, ...)   _BUG_ON_ONCE(cond, __FILE__, __LINE__, 2, "WARNING: bug ",   " (not crashing but process is untrusted now, please report to developers)", __VA_ARGS__)
-#  define CHECK_IF_HOT(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, 0, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
+#  define BUG_ON_HOT(cond, ...)   _BUG_ON_ONCE(cond, __FILE__, __LINE__, DBG_WARN_BUG, "WARNING: bug ",   " (not crashing but process is untrusted now, please report to developers)", __VA_ARGS__)
+#  define CHECK_IF_HOT(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, DBG_WARN_CHK, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
 #  define COUNT_IF_HOT(cond, ...) _COUNT_IF   (cond, __FILE__, __LINE__, __VA_ARGS__)
 # elif !defined(DEBUG_STRICT_ACTION) || (DEBUG_STRICT_ACTION < 3)
 /* default level: BUG_ON() crashes, CHECK_IF() warns */
-#  define BUG_ON_HOT(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, 3, "FATAL: bug ",     "", __VA_ARGS__)
-#  define CHECK_IF_HOT(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, 0, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
+#  define BUG_ON_HOT(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, DBG_FATL_BUG, "FATAL: bug ",     "", __VA_ARGS__)
+#  define CHECK_IF_HOT(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, DBG_WARN_CHK, "WARNING: check ", " (please report to developers)", __VA_ARGS__)
 #  define COUNT_IF_HOT(cond, ...) _COUNT_IF   (cond, __FILE__, __LINE__, __VA_ARGS__)
 # elif defined(DEBUG_STRICT_ACTION) && (DEBUG_STRICT_ACTION >= 3)
 /* Developer/CI level: BUG_ON() crashes, CHECK_IF() crashes */
-#  define BUG_ON_HOT(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, 3, "FATAL: bug ",     "", __VA_ARGS__)
-#  define CHECK_IF_HOT(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, 1, "FATAL: check ",   "", __VA_ARGS__)
+#  define BUG_ON_HOT(cond, ...)   _BUG_ON     (cond, __FILE__, __LINE__, DBG_FATL_BUG, "FATAL: bug ",     "", __VA_ARGS__)
+#  define CHECK_IF_HOT(cond, ...) _BUG_ON_ONCE(cond, __FILE__, __LINE__, DBG_FATL_CHK, "FATAL: check ",   "", __VA_ARGS__)
 #  define COUNT_IF_HOT(cond, ...) _COUNT_IF   (cond, __FILE__, __LINE__, __VA_ARGS__)
 # endif
 #else /* DEBUG_STRICT <= 1 below */

diff --git a/src/debug.c b/src/debug.c
index faf98110cd015df72566abfb1fab500308e3f980..fa8b3c2c3c3278f47dedcf22fcd85ed64b1d44a5 100644 (file)
--- a/src/debug.c
+++ b/src/debug.c
@@ -966,15 +966,16 @@ void ha_stuck_warning(void)
 
 /* Complain with message <msg> on stderr. If <counter> is not NULL, it is
  * atomically incremented, and the message is only printed when the counter
- * was zero, so that the message is only printed once. <taint> is only checked
- * on bit 1, and will taint the process either for a bug (2) or warn (0).
+ * was zero, so that the message is only printed once. <details> is only
+ * checked on DBG_DET_TYP_BUG, and will taint the process either for a
+ * bug or warn.
  */
-void complain(int *counter, const char *msg, int taint)
+void complain(int *counter, const char *msg, uint details)
 {
        if (counter && _HA_ATOMIC_FETCH_ADD(counter, 1))
                return;
        DISGUISE(write(2, msg, strlen(msg)));
-       if (taint & 2)
+       if (details & (DBG_DET_TYP_BUG|DBG_DET_TYP_ABT))
                mark_tainted(TAINTED_BUG);
        else
                mark_tainted(TAINTED_WARN);