/*
* The UCW Library -- Miscellaneous Functions
*
- * (c) 1997--2008 Martin Mares <mj@ucw.cz>
+ * (c) 1997--2009 Martin Mares <mj@ucw.cz>
* (c) 2005 Tomas Valla <tom@ucw.cz>
* (c) 2006 Robert Spalek <robert@ucw.cz>
* (c) 2007 Pavel Charvat <pchar@ucw.cz>
#include "ucw/config.h"
#include <stdarg.h>
-/* Macros for handling structurues, offsets and alignment */
+/*** === Macros for handling structures, offsets and alignment ***/
-#define CHECK_PTR_TYPE(x, type) ((x)-(type)(x) + (type)(x))
-#define PTR_TO(s, i) &((s*)0)->i
-#define OFFSETOF(s, i) ((unsigned int) PTR_TO(s, i))
-#define SKIP_BACK(s, i, p) ((s *)((char *)p - OFFSETOF(s, i)))
+#define CHECK_PTR_TYPE(x, type) ((x)-(type)(x) + (type)(x)) /** Check that a pointer @x is of type @type. Fail compilation if not. **/
+#define PTR_TO(s, i) &((s*)0)->i /** Return OFFSETOF() in form of a pointer. **/
+#define OFFSETOF(s, i) ((uns)offsetof(s, i)) /** Offset of item @i from the start of structure @s **/
+#define SKIP_BACK(s, i, p) ((s *)((char *)p - OFFSETOF(s, i))) /** Given a pointer @p to item @i of structure @s, return a pointer to the start of the struct. **/
+
+/** Align an integer @s to the nearest higher multiple of @a (which should be a power of two) **/
#define ALIGN_TO(s, a) (((s)+a-1)&~(a-1))
+
+/** Align a pointer @p to the nearest higher multiple of @s. **/
#define ALIGN_PTR(p, s) ((uintptr_t)(p) % (s) ? (typeof(p))((uintptr_t)(p) + (s) - (uintptr_t)(p) % (s)) : (p))
+
#define UNALIGNED_PART(ptr, type) (((uintptr_t) (ptr)) % sizeof(type))
-/* Some other macros */
+/*** === Other utility macros ***/
-#define MIN(a,b) (((a)<(b))?(a):(b))
-#define MAX(a,b) (((a)>(b))?(a):(b))
-#define CLAMP(x,min,max) ({ int _t=x; (_t < min) ? min : (_t > max) ? max : _t; })
-#define ABS(x) ((x) < 0 ? -(x) : (x))
-#define ARRAY_SIZE(a) (sizeof(a)/sizeof(*(a)))
-#define STRINGIFY(x) #x
-#define STRINGIFY_EXPANDED(x) STRINGIFY(x)
-#define GLUE(x,y) x##y
-#define GLUE_(x,y) x##_##y
+#define MIN(a,b) (((a)<(b))?(a):(b)) /** Minimum of two numbers **/
+#define MAX(a,b) (((a)>(b))?(a):(b)) /** Maximum of two numbers **/
+#define CLAMP(x,min,max) ({ int _t=x; (_t < min) ? min : (_t > max) ? max : _t; }) /** Clip a number @x to interval [@min,@max] **/
+#define ABS(x) ((x) < 0 ? -(x) : (x)) /** Absolute value **/
+#define ARRAY_SIZE(a) (sizeof(a)/sizeof(*(a))) /** The number of elements of an array **/
+#define STRINGIFY(x) #x /** Convert macro parameter to a string **/
+#define STRINGIFY_EXPANDED(x) STRINGIFY(x) /** Convert an expanded macro parameter to a string **/
+#define GLUE(x,y) x##y /** Glue two tokens together **/
+#define GLUE_(x,y) x##_##y /** Glue two tokens together, separating them by an underscore **/
-#define COMPARE(x,y) do { if ((x)<(y)) return -1; if ((x)>(y)) return 1; } while(0)
-#define REV_COMPARE(x,y) COMPARE(y,x)
+#define COMPARE(x,y) do { if ((x)<(y)) return -1; if ((x)>(y)) return 1; } while(0) /** Numeric comparison function for qsort() **/
+#define REV_COMPARE(x,y) COMPARE(y,x) /** Reverse numeric comparison **/
#define COMPARE_LT(x,y) do { if ((x)<(y)) return 1; if ((x)>(y)) return 0; } while(0)
#define COMPARE_GT(x,y) COMPARE_LT(y,x)
-#define ROL(x, bits) (((x) << (bits)) | ((x) >> (sizeof(uns)*8 - (bits)))) /* Bitwise rotation of an uns to the left */
+#define ROL(x, bits) (((x) << (bits)) | ((uns)(x) >> (sizeof(uns)*8 - (bits)))) /** Bitwise rotation of an unsigned int to the left **/
+#define ROR(x, bits) (((uns)(x) >> (bits)) | ((x) << (sizeof(uns)*8 - (bits)))) /** Bitwise rotation of an unsigned int to the right **/
-/* GCC Extensions */
+/*** === Shortcuts for GCC Extensions ***/
#ifdef __GNUC__
#undef inline
-#define NONRET __attribute__((noreturn))
-#define UNUSED __attribute__((unused))
-#define CONSTRUCTOR __attribute__((constructor))
-#define PACKED __attribute__((packed))
-#define CONST __attribute__((const))
-#define PURE __attribute__((pure))
-#define FORMAT_CHECK(x,y,z) __attribute__((format(x,y,z)))
-#define likely(x) __builtin_expect((x),1)
-#define unlikely(x) __builtin_expect((x),0)
+#define NONRET __attribute__((noreturn)) /** Function does not return **/
+#define UNUSED __attribute__((unused)) /** Variable/parameter is knowingly unused **/
+#define CONSTRUCTOR __attribute__((constructor)) /** Call function upon start of program **/
+#define PACKED __attribute__((packed)) /** Structure should be packed **/
+#define CONST __attribute__((const)) /** Function depends only on arguments **/
+#define PURE __attribute__((pure)) /** Function depends only on arguments and global vars **/
+#define FORMAT_CHECK(x,y,z) __attribute__((format(x,y,z))) /** Checking of printf-like format strings **/
+#define likely(x) __builtin_expect((x),1) /** Use `if (likely(@x))` if @x is almost always true **/
+#define unlikely(x) __builtin_expect((x),0) /** Use `if (unlikely(@x))` to hint that @x is almost always false **/
#if __GNUC__ >= 4 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3
-#define ALWAYS_INLINE inline __attribute__((always_inline))
-#define NO_INLINE __attribute__((noinline))
+#define ALWAYS_INLINE inline __attribute__((always_inline)) /** Forcibly inline **/
+#define NO_INLINE __attribute__((noinline)) /** Forcibly uninline **/
#else
#define ALWAYS_INLINE inline
#endif
#if __GNUC__ >= 4
-#define LIKE_MALLOC __attribute__((malloc))
-#define SENTINEL_CHECK __attribute__((sentinel))
+#define LIKE_MALLOC __attribute__((malloc)) /** Function returns a "new" pointer **/
+#define SENTINEL_CHECK __attribute__((sentinel)) /** The last argument must be NULL **/
#else
#define LIKE_MALLOC
#define SENTINEL_CHECK
#error This program requires the GNU C compiler.
#endif
-/* Logging */
-
-#define L_DEBUG 'D' /* Debugging messages */
-#define L_INFO 'I' /* Informational msgs, warnings and errors */
-#define L_WARN 'W'
-#define L_ERROR 'E'
-#define L_INFO_R 'i' /* Errors caused by external events */
-#define L_WARN_R 'w'
-#define L_ERROR_R 'e'
-#define L_FATAL '!' /* die() */
-
-#define L_SIGHANDLER 0x10000 /* Avoid operations that are unsafe in signal handlers */
-
-extern char *log_title; /* NULL - print no title, default is program name given to log_init() */
-extern char *log_filename; /* Expanded name of the current log file */
-extern int log_pid; /* 0 if shouldn't be logged */
-extern int log_precise_timings; /* Include microsecond timestamps in log messages */
-extern void (*log_die_hook)(void);
-struct tm;
-extern void (*log_switch_hook)(struct tm *tm);
-
-void msg(uns cat, const char *fmt, ...) FORMAT_CHECK(printf,2,3);
-void vmsg(uns cat, const char *fmt, va_list args);
-void die(const char *, ...) NONRET FORMAT_CHECK(printf,1,2);
-void log_init(const char *argv0);
-void log_file(const char *name);
-void log_fork(void); /* Call after fork() to update log_pid */
-
-/* If the log name contains metacharacters for date and time, we switch the logs
- * automatically whenever the name changes. You can disable it and switch explicitly. */
-int log_switch(void);
-void log_switch_disable(void);
-void log_switch_enable(void);
+/***
+ * [[logging]]
+ *
+ * === Basic logging functions (see <<log:,Logging>> and <ucw/log.h> for more)
+ ***/
+
+enum log_levels { /** The available log levels to pass to msg() and friends. **/
+ L_DEBUG=0, // 'D' - Debugging
+ L_INFO, // 'I' - Informational
+ L_WARN, // 'W' - Warning
+ L_ERROR, // 'E' - Error, but non-critical
+ L_INFO_R, // 'i' - An alternative set of levels for messages caused by remote events
+ L_WARN_R, // 'w' (e.g., a packet received via network)
+ L_ERROR_R, // 'e'
+ L_FATAL, // '!' - Fatal error
+ L_MAX
+};
+
+#define LOG_LEVEL_NAMES P(DEBUG) P(INFO) P(WARN) P(ERROR) P(INFO_R) P(WARN_R) P(ERROR_R) P(FATAL)
+
+// Return the letter associated with a given severity level
+#define LS_LEVEL_LETTER(level) ("DIWEiwe!###"[( level )])
+
+#define L_SIGHANDLER 0x80000000 /** Avoid operations that are unsafe in signal handlers **/
+#define L_LOGGER_ERR 0x40000000 /** Used internally to avoid infinite reporting of logging errors **/
+
+/**
+ * This is the basic printf-like function for logging a message.
+ * The @flags contain the log level and possibly other flag bits (like `L_SIGHANDLER`).
+ **/
+void msg(uns flags, const char *fmt, ...) FORMAT_CHECK(printf,2,3);
+void vmsg(uns flags, const char *fmt, va_list args); /** A vararg version of msg(). **/
+void die(const char *, ...) NONRET FORMAT_CHECK(printf,1,2); /** Log a fatal error message and exit the program. **/
+
+extern char *log_title; /** An optional log message title. Set to program name by log_init(). **/
+extern int log_pid; /** An optional PID printed in each log message. Set to 0 if it shouldn't be logged. **/
+extern void (*log_die_hook)(void); /** An optional function called just before die() exists. **/
+
+void log_init(const char *argv0); /** Set @log_title to the program name extracted from @argv[0]. **/
+void log_fork(void); /** Call after fork() to update @log_pid. **/
+void log_file(const char *name); /** Establish logging to the named file. Also redirect stderr there. **/
void assert_failed(const char *assertion, const char *file, int line) NONRET;
void assert_failed_noinfo(void) NONRET;
#ifdef DEBUG_ASSERTS
+/**
+ * Check an assertion. If the condition @x is false, stop the program with a fatal error.
+ * Assertion checks are compiled only when `DEBUG_ASSERTS` is defined.
+ **/
#define ASSERT(x) ({ if (unlikely(!(x))) assert_failed(#x, __FILE__, __LINE__); 1; })
#else
#define ASSERT(x) ({ if (__builtin_constant_p(x) && !(x)) assert_failed_noinfo(); 1; })
#define COMPILE_ASSERT(name,x) typedef char _COMPILE_ASSERT_##name[!!(x)-1]
#ifdef LOCAL_DEBUG
-#define DBG(x,y...) msg(L_DEBUG, x,##y)
+#define DBG(x,y...) msg(L_DEBUG, x,##y) /** If `LOCAL_DEBUG` is defined before including <ucw/lib.h>, log a debug message. Otherwise do nothing. **/
#else
#define DBG(x,y...) do { } while(0)
#endif
-/* Memory allocation */
-
-#define xmalloc ucw_xmalloc
-#define xrealloc ucw_xrealloc
-#define xfree ucw_xfree
+/*** === Memory allocation ***/
/*
* Unfortunately, several libraries we might want to link to define
* their own xmalloc and we don't want to interfere with them, hence
* the renaming.
*/
-void *xmalloc(uns) LIKE_MALLOC;
-void *xrealloc(void *, uns);
-void xfree(void *);
+#define xmalloc ucw_xmalloc
+#define xrealloc ucw_xrealloc
+#define xfree ucw_xfree
-void *xmalloc_zero(uns) LIKE_MALLOC;
-char *xstrdup(const char *) LIKE_MALLOC;
+void *xmalloc(size_t) LIKE_MALLOC; /** Allocate memory and die() if there is none. **/
+void *xrealloc(void *, size_t); /** Reallocate memory and die() if there is none. **/
+void xfree(void *); /** Free memory allocated by xmalloc() or xrealloc(). **/
-/* timer.c */
+void *xmalloc_zero(size_t) LIKE_MALLOC; /** Allocate memory and fill it by zeroes. **/
+char *xstrdup(const char *) LIKE_MALLOC; /** Make a xmalloc()'ed copy of a string. Returns NULL for NULL string. **/
-timestamp_t get_timestamp(void);
+/*** === Trivial timers (timer.c) ***/
-void init_timer(timestamp_t *timer);
-uns get_timer(timestamp_t *timer);
-uns switch_timer(timestamp_t *old, timestamp_t *new);
+timestamp_t get_timestamp(void); /** Get current time as a millisecond timestamp. **/
-/* random.c */
+void init_timer(timestamp_t *timer); /** Initialize a timer. **/
+uns get_timer(timestamp_t *timer); /** Get the number of milliseconds since last init/get of a timer. **/
+uns switch_timer(timestamp_t *oldt, timestamp_t *newt); /** Stop ticking of one timer and resume another. **/
-uns random_u32(void);
-uns random_max(uns max);
-u64 random_u64(void);
-u64 random_max_u64(u64 max);
+/*** === Random numbers (random.c) ***/
+
+uns random_u32(void); /** Return a pseudorandom 32-bit number. **/
+uns random_max(uns max); /** Return a pseudorandom 32-bit number in range [0,@max). **/
+u64 random_u64(void); /** Return a pseudorandom 64-bit number. **/
+u64 random_max_u64(u64 max); /** Return a pseudorandom 64-bit number in range [0,@max). **/
/* mmap.c */
void setproctitle(const char *msg, ...) FORMAT_CHECK(printf,1,2);
char *getproctitle(void);
-/* randomkey.c */
-
-void randomkey(byte *buf, uns size);
-
/* exitstatus.c */
#define EXIT_STATUS_MSG_SIZE 32
void handle_signal(int signum);
void unhandle_signal(int signum);
-ucw_sighandler_t set_signal_handler(int signum, ucw_sighandler_t new);
+ucw_sighandler_t set_signal_handler(int signum, ucw_sighandler_t newh);
/* bigalloc.c */
projects / libucw.git / blobdiff