PostgreSQL Source Code  git master
elog.h
Go to the documentation of this file.
1 /*-------------------------------------------------------------------------
2  *
3  * elog.h
4  * POSTGRES error reporting/logging definitions.
5  *
6  *
7  * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
8  * Portions Copyright (c) 1994, Regents of the University of California
9  *
10  * src/include/utils/elog.h
11  *
12  *-------------------------------------------------------------------------
13  */
14 #ifndef ELOG_H
15 #define ELOG_H
16 
17 #include <setjmp.h>
18 
19 /* Error level codes */
20 #define DEBUG5 10 /* Debugging messages, in categories of
21  * decreasing detail. */
22 #define DEBUG4 11
23 #define DEBUG3 12
24 #define DEBUG2 13
25 #define DEBUG1 14 /* used by GUC debug_* variables */
26 #define LOG 15 /* Server operational messages; sent only to
27  * server log by default. */
28 #define LOG_SERVER_ONLY 16 /* Same as LOG for server reporting, but never
29  * sent to client. */
30 #define COMMERROR LOG_SERVER_ONLY /* Client communication problems; same as
31  * LOG for server reporting, but never
32  * sent to client. */
33 #define INFO 17 /* Messages specifically requested by user (eg
34  * VACUUM VERBOSE output); always sent to
35  * client regardless of client_min_messages,
36  * but by default not sent to server log. */
37 #define NOTICE 18 /* Helpful messages to users about query
38  * operation; sent to client and not to server
39  * log by default. */
40 #define WARNING 19 /* Warnings. NOTICE is for expected messages
41  * like implicit sequence creation by SERIAL.
42  * WARNING is for unexpected messages. */
43 #define ERROR 20 /* user error - abort transaction; return to
44  * known state */
45 /* Save ERROR value in PGERROR so it can be restored when Win32 includes
46  * modify it. We have to use a constant rather than ERROR because macros
47  * are expanded only when referenced outside macros.
48  */
49 #ifdef WIN32
50 #define PGERROR 20
51 #endif
52 #define FATAL 21 /* fatal error - abort process */
53 #define PANIC 22 /* take down the other backends with me */
54 
55  /* #define DEBUG DEBUG1 */ /* Backward compatibility with pre-7.3 */
56 
57 
58 /* macros for representing SQLSTATE strings compactly */
59 #define PGSIXBIT(ch) (((ch) - '0') & 0x3F)
60 #define PGUNSIXBIT(val) (((val) & 0x3F) + '0')
61 
62 #define MAKE_SQLSTATE(ch1,ch2,ch3,ch4,ch5) \
63  (PGSIXBIT(ch1) + (PGSIXBIT(ch2) << 6) + (PGSIXBIT(ch3) << 12) + \
64  (PGSIXBIT(ch4) << 18) + (PGSIXBIT(ch5) << 24))
65 
66 /* These macros depend on the fact that '0' becomes a zero in PGSIXBIT */
67 #define ERRCODE_TO_CATEGORY(ec) ((ec) & ((1 << 12) - 1))
68 #define ERRCODE_IS_CATEGORY(ec) (((ec) & ~((1 << 12) - 1)) == 0)
69 
70 /* SQLSTATE codes for errors are defined in a separate file */
71 #include "utils/errcodes.h"
72 
73 /*
74  * Provide a way to prevent "errno" from being accidentally used inside an
75  * elog() or ereport() invocation. Since we know that some operating systems
76  * define errno as something involving a function call, we'll put a local
77  * variable of the same name as that function in the local scope to force a
78  * compile error. On platforms that don't define errno in that way, nothing
79  * happens, so we get no warning ... but we can live with that as long as it
80  * happens on some popular platforms.
81  */
82 #if defined(errno) && defined(__linux__)
83 #define pg_prevent_errno_in_scope() int __errno_location pg_attribute_unused()
84 #elif defined(errno) && (defined(__darwin__) || defined(__freebsd__))
85 #define pg_prevent_errno_in_scope() int __error pg_attribute_unused()
86 #else
87 #define pg_prevent_errno_in_scope()
88 #endif
89 
90 
91 /*----------
92  * New-style error reporting API: to be used in this way:
93  * ereport(ERROR,
94  * (errcode(ERRCODE_UNDEFINED_CURSOR),
95  * errmsg("portal \"%s\" not found", stmt->portalname),
96  * ... other errxxx() fields as needed ...));
97  *
98  * The error level is required, and so is a primary error message (errmsg
99  * or errmsg_internal). All else is optional. errcode() defaults to
100  * ERRCODE_INTERNAL_ERROR if elevel is ERROR or more, ERRCODE_WARNING
101  * if elevel is WARNING, or ERRCODE_SUCCESSFUL_COMPLETION if elevel is
102  * NOTICE or below.
103  *
104  * ereport_domain() allows a message domain to be specified, for modules that
105  * wish to use a different message catalog from the backend's. To avoid having
106  * one copy of the default text domain per .o file, we define it as NULL here
107  * and have errstart insert the default text domain. Modules can either use
108  * ereport_domain() directly, or preferably they can override the TEXTDOMAIN
109  * macro.
110  *
111  * If elevel >= ERROR, the call will not return; we try to inform the compiler
112  * of that via pg_unreachable(). However, no useful optimization effect is
113  * obtained unless the compiler sees elevel as a compile-time constant, else
114  * we're just adding code bloat. So, if __builtin_constant_p is available,
115  * use that to cause the second if() to vanish completely for non-constant
116  * cases. We avoid using a local variable because it's not necessary and
117  * prevents gcc from making the unreachability deduction at optlevel -O0.
118  *----------
119  */
120 #ifdef HAVE__BUILTIN_CONSTANT_P
121 #define ereport_domain(elevel, domain, rest) \
122  do { \
123  pg_prevent_errno_in_scope(); \
124  if (errstart(elevel, __FILE__, __LINE__, PG_FUNCNAME_MACRO, domain)) \
125  errfinish rest; \
126  if (__builtin_constant_p(elevel) && (elevel) >= ERROR) \
127  pg_unreachable(); \
128  } while(0)
129 #else /* !HAVE__BUILTIN_CONSTANT_P */
130 #define ereport_domain(elevel, domain, rest) \
131  do { \
132  const int elevel_ = (elevel); \
133  pg_prevent_errno_in_scope(); \
134  if (errstart(elevel_, __FILE__, __LINE__, PG_FUNCNAME_MACRO, domain)) \
135  errfinish rest; \
136  if (elevel_ >= ERROR) \
137  pg_unreachable(); \
138  } while(0)
139 #endif /* HAVE__BUILTIN_CONSTANT_P */
140 
141 #define ereport(elevel, rest) \
142  ereport_domain(elevel, TEXTDOMAIN, rest)
143 
144 #define TEXTDOMAIN NULL
145 
146 extern bool errstart(int elevel, const char *filename, int lineno,
147  const char *funcname, const char *domain);
148 extern void errfinish(int dummy,...);
149 
150 extern int errcode(int sqlerrcode);
151 
152 extern int errcode_for_file_access(void);
153 extern int errcode_for_socket_access(void);
154 
155 extern int errmsg(const char *fmt,...) pg_attribute_printf(1, 2);
156 extern int errmsg_internal(const char *fmt,...) pg_attribute_printf(1, 2);
157 
158 extern int errmsg_plural(const char *fmt_singular, const char *fmt_plural,
159  unsigned long n,...) pg_attribute_printf(1, 4) pg_attribute_printf(2, 4);
160 
161 extern int errdetail(const char *fmt,...) pg_attribute_printf(1, 2);
162 extern int errdetail_internal(const char *fmt,...) pg_attribute_printf(1, 2);
163 
164 extern int errdetail_log(const char *fmt,...) pg_attribute_printf(1, 2);
165 
166 extern int errdetail_log_plural(const char *fmt_singular,
167  const char *fmt_plural,
168  unsigned long n,...) pg_attribute_printf(1, 4) pg_attribute_printf(2, 4);
169 
170 extern int errdetail_plural(const char *fmt_singular, const char *fmt_plural,
171  unsigned long n,...) pg_attribute_printf(1, 4) pg_attribute_printf(2, 4);
172 
173 extern int errhint(const char *fmt,...) pg_attribute_printf(1, 2);
174 
175 /*
176  * errcontext() is typically called in error context callback functions, not
177  * within an ereport() invocation. The callback function can be in a different
178  * module than the ereport() call, so the message domain passed in errstart()
179  * is not usually the correct domain for translating the context message.
180  * set_errcontext_domain() first sets the domain to be used, and
181  * errcontext_msg() passes the actual message.
182  */
183 #define errcontext set_errcontext_domain(TEXTDOMAIN), errcontext_msg
184 
185 extern int set_errcontext_domain(const char *domain);
186 
187 extern int errcontext_msg(const char *fmt,...) pg_attribute_printf(1, 2);
188 
189 extern int errhidestmt(bool hide_stmt);
190 extern int errhidecontext(bool hide_ctx);
191 
192 extern int errbacktrace(void);
193 
194 extern int errfunction(const char *funcname);
195 extern int errposition(int cursorpos);
196 
197 extern int internalerrposition(int cursorpos);
198 extern int internalerrquery(const char *query);
199 
200 extern int err_generic_string(int field, const char *str);
201 
202 extern int geterrcode(void);
203 extern int geterrposition(void);
204 extern int getinternalerrposition(void);
205 
206 
207 /*----------
208  * Old-style error reporting API: to be used in this way:
209  * elog(ERROR, "portal \"%s\" not found", stmt->portalname);
210  *----------
211  */
212 /*
213  * Using variadic macros, we can give the compiler a hint about the
214  * call not returning when elevel >= ERROR. See comments for ereport().
215  * Note that historically elog() has called elog_start (which saves errno)
216  * before evaluating "elevel", so we preserve that behavior here.
217  */
218 #ifdef HAVE__BUILTIN_CONSTANT_P
219 #define elog(elevel, ...) \
220  do { \
221  pg_prevent_errno_in_scope(); \
222  elog_start(__FILE__, __LINE__, PG_FUNCNAME_MACRO); \
223  elog_finish(elevel, __VA_ARGS__); \
224  if (__builtin_constant_p(elevel) && (elevel) >= ERROR) \
225  pg_unreachable(); \
226  } while(0)
227 #else /* !HAVE__BUILTIN_CONSTANT_P */
228 #define elog(elevel, ...) \
229  do { \
230  pg_prevent_errno_in_scope(); \
231  elog_start(__FILE__, __LINE__, PG_FUNCNAME_MACRO); \
232  { \
233  const int elevel_ = (elevel); \
234  elog_finish(elevel_, __VA_ARGS__); \
235  if (elevel_ >= ERROR) \
236  pg_unreachable(); \
237  } \
238  } while(0)
239 #endif /* HAVE__BUILTIN_CONSTANT_P */
240 
241 extern void elog_start(const char *filename, int lineno, const char *funcname);
242 extern void elog_finish(int elevel, const char *fmt,...) pg_attribute_printf(2, 3);
243 
244 
245 /* Support for constructing error strings separately from ereport() calls */
246 
247 extern void pre_format_elog_string(int errnumber, const char *domain);
248 extern char *format_elog_string(const char *fmt,...) pg_attribute_printf(1, 2);
249 
250 
251 /* Support for attaching context information to error reports */
252 
253 typedef struct ErrorContextCallback
254 {
255  struct ErrorContextCallback *previous;
256  void (*callback) (void *arg);
257  void *arg;
259 
261 
262 
263 /*----------
264  * API for catching ereport(ERROR) exits. Use these macros like so:
265  *
266  * PG_TRY();
267  * {
268  * ... code that might throw ereport(ERROR) ...
269  * }
270  * PG_CATCH();
271  * {
272  * ... error recovery code ...
273  * }
274  * PG_END_TRY();
275  *
276  * (The braces are not actually necessary, but are recommended so that
277  * pgindent will indent the construct nicely.) The error recovery code
278  * can either do PG_RE_THROW to propagate the error outwards, or do a
279  * (sub)transaction abort. Failure to do so may leave the system in an
280  * inconsistent state for further processing.
281  *
282  * For the common case that the error recovery code and the cleanup in the
283  * normal code path are identical, the following can be used instead:
284  *
285  * PG_TRY();
286  * {
287  * ... code that might throw ereport(ERROR) ...
288  * }
289  * PG_FINALLY();
290  * {
291  * ... cleanup code ...
292  * }
293  * PG_END_TRY();
294  *
295  * The cleanup code will be run in either case, and any error will be rethrown
296  * afterwards.
297  *
298  * You cannot use both PG_CATCH() and PG_FINALLY() in the same
299  * PG_TRY()/PG_END_TRY() block.
300  *
301  * Note: while the system will correctly propagate any new ereport(ERROR)
302  * occurring in the recovery section, there is a small limit on the number
303  * of levels this will work for. It's best to keep the error recovery
304  * section simple enough that it can't generate any new errors, at least
305  * not before popping the error stack.
306  *
307  * Note: an ereport(FATAL) will not be caught by this construct; control will
308  * exit straight through proc_exit(). Therefore, do NOT put any cleanup
309  * of non-process-local resources into the error recovery section, at least
310  * not without taking thought for what will happen during ereport(FATAL).
311  * The PG_ENSURE_ERROR_CLEANUP macros provided by storage/ipc.h may be
312  * helpful in such cases.
313  *
314  * Note: if a local variable of the function containing PG_TRY is modified
315  * in the PG_TRY section and used in the PG_CATCH section, that variable
316  * must be declared "volatile" for POSIX compliance. This is not mere
317  * pedantry; we have seen bugs from compilers improperly optimizing code
318  * away when such a variable was not marked. Beware that gcc's -Wclobbered
319  * warnings are just about entirely useless for catching such oversights.
320  *----------
321  */
322 #define PG_TRY() \
323  do { \
324  sigjmp_buf *_save_exception_stack = PG_exception_stack; \
325  ErrorContextCallback *_save_context_stack = error_context_stack; \
326  sigjmp_buf _local_sigjmp_buf; \
327  bool _do_rethrow = false; \
328  if (sigsetjmp(_local_sigjmp_buf, 0) == 0) \
329  { \
330  PG_exception_stack = &_local_sigjmp_buf
331 
332 #define PG_CATCH() \
333  } \
334  else \
335  { \
336  PG_exception_stack = _save_exception_stack; \
337  error_context_stack = _save_context_stack
338 
339 #define PG_FINALLY() \
340  } \
341  else \
342  _do_rethrow = true; \
343  { \
344  PG_exception_stack = _save_exception_stack; \
345  error_context_stack = _save_context_stack
346 
347 #define PG_END_TRY() \
348  } \
349  if (_do_rethrow) \
350  PG_RE_THROW(); \
351  PG_exception_stack = _save_exception_stack; \
352  error_context_stack = _save_context_stack; \
353  } while (0)
354 
355 /*
356  * Some compilers understand pg_attribute_noreturn(); for other compilers,
357  * insert pg_unreachable() so that the compiler gets the point.
358  */
359 #ifdef HAVE_PG_ATTRIBUTE_NORETURN
360 #define PG_RE_THROW() \
361  pg_re_throw()
362 #else
363 #define PG_RE_THROW() \
364  (pg_re_throw(), pg_unreachable())
365 #endif
366 
367 extern PGDLLIMPORT sigjmp_buf *PG_exception_stack;
368 
369 
370 /* Stuff that error handlers might want to use */
371 
372 /*
373  * ErrorData holds the data accumulated during any one ereport() cycle.
374  * Any non-NULL pointers must point to palloc'd data.
375  * (The const pointers are an exception; we assume they point at non-freeable
376  * constant strings.)
377  */
378 typedef struct ErrorData
379 {
380  int elevel; /* error level */
381  bool output_to_server; /* will report to server log? */
382  bool output_to_client; /* will report to client? */
383  bool show_funcname; /* true to force funcname inclusion */
384  bool hide_stmt; /* true to prevent STATEMENT: inclusion */
385  bool hide_ctx; /* true to prevent CONTEXT: inclusion */
386  const char *filename; /* __FILE__ of ereport() call */
387  int lineno; /* __LINE__ of ereport() call */
388  const char *funcname; /* __func__ of ereport() call */
389  const char *domain; /* message domain */
390  const char *context_domain; /* message domain for context message */
391  int sqlerrcode; /* encoded ERRSTATE */
392  char *message; /* primary error message (translated) */
393  char *detail; /* detail error message */
394  char *detail_log; /* detail error message for server log only */
395  char *hint; /* hint message */
396  char *context; /* context message */
397  char *backtrace; /* backtrace */
398  const char *message_id; /* primary message's id (original string) */
399  char *schema_name; /* name of schema */
400  char *table_name; /* name of table */
401  char *column_name; /* name of column */
402  char *datatype_name; /* name of datatype */
403  char *constraint_name; /* name of constraint */
404  int cursorpos; /* cursor index into query string */
405  int internalpos; /* cursor index into internalquery */
406  char *internalquery; /* text of internally-generated query */
407  int saved_errno; /* errno at entry */
408 
409  /* context containing associated non-constant strings */
411 } ErrorData;
412 
413 extern void EmitErrorReport(void);
414 extern ErrorData *CopyErrorData(void);
415 extern void FreeErrorData(ErrorData *edata);
416 extern void FlushErrorState(void);
417 extern void ReThrowError(ErrorData *edata) pg_attribute_noreturn();
418 extern void ThrowErrorData(ErrorData *edata);
419 extern void pg_re_throw(void) pg_attribute_noreturn();
420 
421 extern char *GetErrorContextStack(void);
422 
423 /* Hook for intercepting messages before they are sent to the server log */
424 typedef void (*emit_log_hook_type) (ErrorData *edata);
426 
427 
428 /* GUC-configurable parameters */
429 
430 typedef enum
431 {
432  PGERROR_TERSE, /* single-line error messages */
433  PGERROR_DEFAULT, /* recommended style */
434  PGERROR_VERBOSE /* all the facts, ma'am */
436 
437 extern int Log_error_verbosity;
438 extern char *Log_line_prefix;
439 extern int Log_destination;
440 extern char *Log_destination_string;
441 extern bool syslog_sequence_numbers;
442 extern bool syslog_split_messages;
443 
444 /* Log destination bitmap */
445 #define LOG_DESTINATION_STDERR 1
446 #define LOG_DESTINATION_SYSLOG 2
447 #define LOG_DESTINATION_EVENTLOG 4
448 #define LOG_DESTINATION_CSVLOG 8
449 
450 /* Other exported functions */
451 extern void DebugFileOpen(void);
452 extern char *unpack_sql_state(int sql_state);
453 extern bool in_error_recursion_trouble(void);
454 
455 #ifdef HAVE_SYSLOG
456 extern void set_syslog_parameters(const char *ident, int facility);
457 #endif
458 
459 /*
460  * Write errors to stderr (or by equal means when stderr is
461  * not available). Used before ereport/elog can be used
462  * safely (memory context, GUC load etc)
463  */
464 extern void write_stderr(const char *fmt,...) pg_attribute_printf(1, 2);
465 
466 #endif /* ELOG_H */
char * schema_name
Definition: elog.h:399
bool hide_stmt
Definition: elog.h:384
int errbacktrace(void)
Definition: elog.c:844
int errcode_for_file_access(void)
Definition: elog.c:631
int errposition(int cursorpos)
Definition: elog.c:1207
char * format_elog_string(const char *fmt,...) pg_attribute_printf(1
int sqlerrcode
Definition: elog.h:391
void elog_start(const char *filename, int lineno, const char *funcname)
Definition: elog.c:1380
void errfinish(int dummy,...)
Definition: elog.c:440
const char * funcname
Definition: elog.h:388
void ReThrowError(ErrorData *edata) pg_attribute_noreturn()
Definition: elog.c:1763
ErrorData * CopyErrorData(void)
Definition: elog.c:1584
int int int pg_attribute_printf(2, 4)
char * Log_line_prefix
Definition: elog.c:108
int lineno
Definition: elog.h:387
PGDLLIMPORT sigjmp_buf * PG_exception_stack
Definition: elog.c:93
char * internalquery
Definition: elog.h:406
int int errmsg_internal(const char *fmt,...) pg_attribute_printf(1
int int errhidestmt(bool hide_stmt)
Definition: elog.c:1150
void FreeErrorData(ErrorData *edata)
Definition: elog.c:1640
char struct ErrorContextCallback ErrorContextCallback
struct ErrorContextCallback * previous
Definition: elog.h:255
int int int errmsg_plural(const char *fmt_singular, const char *fmt_plural, unsigned long n,...) pg_attribute_printf(1
#define PGDLLIMPORT
Definition: c.h:1272
int cursorpos
Definition: elog.h:404
const char * context_domain
Definition: elog.h:390
int errhidecontext(bool hide_ctx)
Definition: elog.c:1169
bool syslog_sequence_numbers
Definition: elog.c:111
char * GetErrorContextStack(void)
Definition: elog.c:1886
const char * filename
Definition: elog.h:386
char * detail_log
Definition: elog.h:394
int errdetail_plural(const char *fmt_singular, const char *fmt_plural, unsigned long n,...) pg_attribute_printf(1
int errcode_for_socket_access(void)
Definition: elog.c:702
int set_errcontext_domain(const char *domain)
Definition: elog.c:1130
static void callback(struct sockaddr *addr, struct sockaddr *mask, void *unused)
Definition: test_ifaddrs.c:48
int geterrcode(void)
Definition: elog.c:1322
int geterrposition(void)
Definition: elog.c:1339
int internalerrquery(const char *query)
Definition: elog.c:1243
char * table_name
Definition: elog.h:400
bool output_to_server
Definition: elog.h:381
int internalpos
Definition: elog.h:405
int saved_errno
Definition: elog.h:407
bool hide_ctx
Definition: elog.h:385
bool errstart(int elevel, const char *filename, int lineno, const char *funcname, const char *domain)
Definition: elog.c:234
void ThrowErrorData(ErrorData *edata)
Definition: elog.c:1703
const char * ident
Definition: memnodes.h:89
int internalerrposition(int cursorpos)
Definition: elog.c:1223
char * backtrace
Definition: elog.h:397
char * datatype_name
Definition: elog.h:402
int elevel
Definition: elog.h:380
void elog_finish(int elevel, const char *fmt,...) pg_attribute_printf(2
static int elevel
Definition: vacuumlazy.c:143
char * detail
Definition: elog.h:393
void EmitErrorReport(void)
Definition: elog.c:1533
int int errdetail_internal(const char *fmt,...) pg_attribute_printf(1
PGDLLIMPORT emit_log_hook_type emit_log_hook
Definition: elog.c:104
const char * message_id
Definition: elog.h:398
int Log_destination
Definition: elog.c:109
bool show_funcname
Definition: elog.h:383
int errmsg(const char *fmt,...) pg_attribute_printf(1
void(* emit_log_hook_type)(ErrorData *edata)
Definition: elog.h:424
char * column_name
Definition: elog.h:401
int err_generic_string(int field, const char *str)
Definition: elog.c:1273
int getinternalerrposition(void)
Definition: elog.c:1356
PGErrorVerbosity
Definition: elog.h:430
char * hint
Definition: elog.h:395
void void pre_format_elog_string(int errnumber, const char *domain)
Definition: elog.c:1491
int errcontext_msg(const char *fmt,...) pg_attribute_printf(1
char * context
Definition: elog.h:396
struct MemoryContextData * assoc_context
Definition: elog.h:410
#define pg_attribute_noreturn()
Definition: c.h:147
int errhint(const char *fmt,...) pg_attribute_printf(1
int int int errdetail_log(const char *fmt,...) pg_attribute_printf(1
static char * filename
Definition: pg_dumpall.c:90
bool in_error_recursion_trouble(void)
Definition: elog.c:197
void pg_re_throw(void) pg_attribute_noreturn()
Definition: elog.c:1824
void write_stderr(const char *fmt,...) pg_attribute_printf(1
void * arg
bool syslog_split_messages
Definition: elog.c:112
int errfunction(const char *funcname)
Definition: elog.c:1190
void FlushErrorState(void)
Definition: elog.c:1678
int errdetail(const char *fmt,...) pg_attribute_printf(1
int Log_error_verbosity
Definition: elog.c:107
const char * domain
Definition: elog.h:389
char * constraint_name
Definition: elog.h:403
char * Log_destination_string
Definition: elog.c:110
char * unpack_sql_state(int sql_state)
Definition: elog.c:2939
int int int int errdetail_log_plural(const char *fmt_singular, const char *fmt_plural, unsigned long n,...) pg_attribute_printf(1
bool output_to_client
Definition: elog.h:382
char * message
Definition: elog.h:392
void DebugFileOpen(void)
Definition: elog.c:1953
PGDLLIMPORT ErrorContextCallback * error_context_stack
Definition: elog.c:91
struct ErrorData ErrorData
int errcode(int sqlerrcode)
Definition: elog.c:608