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elog.h
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1 /*-------------------------------------------------------------------------
2  *
3  * elog.h
4  * POSTGRES error reporting/logging definitions.
5  *
6  *
7  * Portions Copyright (c) 1996-2020, 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  * Before Postgres v12, extra parentheses were required around the
105  * list of auxiliary function calls; that's now optional.
106  *
107  * ereport_domain() allows a message domain to be specified, for modules that
108  * wish to use a different message catalog from the backend's. To avoid having
109  * one copy of the default text domain per .o file, we define it as NULL here
110  * and have errstart insert the default text domain. Modules can either use
111  * ereport_domain() directly, or preferably they can override the TEXTDOMAIN
112  * macro.
113  *
114  * When __builtin_constant_p is available and elevel >= ERROR we make a call
115  * to errstart_cold() instead of errstart(). This version of the function is
116  * marked with pg_attribute_cold which will coax supporting compilers into
117  * generating code which is more optimized towards non-ERROR cases. Because
118  * we use __builtin_constant_p() in the condition, when elevel is not a
119  * compile-time constant, or if it is, but it's < ERROR, the compiler has no
120  * need to generate any code for this branch. It can simply call errstart()
121  * unconditionally.
122  *
123  * If elevel >= ERROR, the call will not return; we try to inform the compiler
124  * of that via pg_unreachable(). However, no useful optimization effect is
125  * obtained unless the compiler sees elevel as a compile-time constant, else
126  * we're just adding code bloat. So, if __builtin_constant_p is available,
127  * use that to cause the second if() to vanish completely for non-constant
128  * cases. We avoid using a local variable because it's not necessary and
129  * prevents gcc from making the unreachability deduction at optlevel -O0.
130  *----------
131  */
132 #ifdef HAVE__BUILTIN_CONSTANT_P
133 #define ereport_domain(elevel, domain, ...) \
134  do { \
135  pg_prevent_errno_in_scope(); \
136  if (__builtin_constant_p(elevel) && (elevel) >= ERROR ? \
137  errstart_cold(elevel, domain) : \
138  errstart(elevel, domain)) \
139  __VA_ARGS__, errfinish(__FILE__, __LINE__, PG_FUNCNAME_MACRO); \
140  if (__builtin_constant_p(elevel) && (elevel) >= ERROR) \
141  pg_unreachable(); \
142  } while(0)
143 #else /* !HAVE__BUILTIN_CONSTANT_P */
144 #define ereport_domain(elevel, domain, ...) \
145  do { \
146  const int elevel_ = (elevel); \
147  pg_prevent_errno_in_scope(); \
148  if (errstart(elevel_, domain)) \
149  __VA_ARGS__, errfinish(__FILE__, __LINE__, PG_FUNCNAME_MACRO); \
150  if (elevel_ >= ERROR) \
151  pg_unreachable(); \
152  } while(0)
153 #endif /* HAVE__BUILTIN_CONSTANT_P */
154 
155 #define ereport(elevel, ...) \
156  ereport_domain(elevel, TEXTDOMAIN, __VA_ARGS__)
157 
158 #define TEXTDOMAIN NULL
159 
160 extern bool message_level_is_interesting(int elevel);
161 
162 extern bool errstart(int elevel, const char *domain);
163 extern pg_attribute_cold bool errstart_cold(int elevel, const char *domain);
164 extern void errfinish(const char *filename, int lineno, const char *funcname);
165 
166 extern int errcode(int sqlerrcode);
167 
168 extern int errcode_for_file_access(void);
169 extern int errcode_for_socket_access(void);
170 
171 extern int errmsg(const char *fmt,...) pg_attribute_printf(1, 2);
172 extern int errmsg_internal(const char *fmt,...) pg_attribute_printf(1, 2);
173 
174 extern int errmsg_plural(const char *fmt_singular, const char *fmt_plural,
175  unsigned long n,...) pg_attribute_printf(1, 4) pg_attribute_printf(2, 4);
176 
177 extern int errdetail(const char *fmt,...) pg_attribute_printf(1, 2);
178 extern int errdetail_internal(const char *fmt,...) pg_attribute_printf(1, 2);
179 
180 extern int errdetail_log(const char *fmt,...) pg_attribute_printf(1, 2);
181 
182 extern int errdetail_log_plural(const char *fmt_singular,
183  const char *fmt_plural,
184  unsigned long n,...) pg_attribute_printf(1, 4) pg_attribute_printf(2, 4);
185 
186 extern int errdetail_plural(const char *fmt_singular, const char *fmt_plural,
187  unsigned long n,...) pg_attribute_printf(1, 4) pg_attribute_printf(2, 4);
188 
189 extern int errhint(const char *fmt,...) pg_attribute_printf(1, 2);
190 
191 /*
192  * errcontext() is typically called in error context callback functions, not
193  * within an ereport() invocation. The callback function can be in a different
194  * module than the ereport() call, so the message domain passed in errstart()
195  * is not usually the correct domain for translating the context message.
196  * set_errcontext_domain() first sets the domain to be used, and
197  * errcontext_msg() passes the actual message.
198  */
199 #define errcontext set_errcontext_domain(TEXTDOMAIN), errcontext_msg
200 
201 extern int set_errcontext_domain(const char *domain);
202 
203 extern int errcontext_msg(const char *fmt,...) pg_attribute_printf(1, 2);
204 
205 extern int errhidestmt(bool hide_stmt);
206 extern int errhidecontext(bool hide_ctx);
207 
208 extern int errbacktrace(void);
209 
210 extern int errfunction(const char *funcname);
211 extern int errposition(int cursorpos);
212 
213 extern int internalerrposition(int cursorpos);
214 extern int internalerrquery(const char *query);
215 
216 extern int err_generic_string(int field, const char *str);
217 
218 extern int geterrcode(void);
219 extern int geterrposition(void);
220 extern int getinternalerrposition(void);
221 
222 
223 /*----------
224  * Old-style error reporting API: to be used in this way:
225  * elog(ERROR, "portal \"%s\" not found", stmt->portalname);
226  *----------
227  */
228 #define elog(elevel, ...) \
229  ereport(elevel, errmsg_internal(__VA_ARGS__))
230 
231 
232 /* Support for constructing error strings separately from ereport() calls */
233 
234 extern void pre_format_elog_string(int errnumber, const char *domain);
235 extern char *format_elog_string(const char *fmt,...) pg_attribute_printf(1, 2);
236 
237 
238 /* Support for attaching context information to error reports */
239 
240 typedef struct ErrorContextCallback
241 {
242  struct ErrorContextCallback *previous;
243  void (*callback) (void *arg);
244  void *arg;
246 
248 
249 
250 /*----------
251  * API for catching ereport(ERROR) exits. Use these macros like so:
252  *
253  * PG_TRY();
254  * {
255  * ... code that might throw ereport(ERROR) ...
256  * }
257  * PG_CATCH();
258  * {
259  * ... error recovery code ...
260  * }
261  * PG_END_TRY();
262  *
263  * (The braces are not actually necessary, but are recommended so that
264  * pgindent will indent the construct nicely.) The error recovery code
265  * can either do PG_RE_THROW to propagate the error outwards, or do a
266  * (sub)transaction abort. Failure to do so may leave the system in an
267  * inconsistent state for further processing.
268  *
269  * For the common case that the error recovery code and the cleanup in the
270  * normal code path are identical, the following can be used instead:
271  *
272  * PG_TRY();
273  * {
274  * ... code that might throw ereport(ERROR) ...
275  * }
276  * PG_FINALLY();
277  * {
278  * ... cleanup code ...
279  * }
280  * PG_END_TRY();
281  *
282  * The cleanup code will be run in either case, and any error will be rethrown
283  * afterwards.
284  *
285  * You cannot use both PG_CATCH() and PG_FINALLY() in the same
286  * PG_TRY()/PG_END_TRY() block.
287  *
288  * Note: while the system will correctly propagate any new ereport(ERROR)
289  * occurring in the recovery section, there is a small limit on the number
290  * of levels this will work for. It's best to keep the error recovery
291  * section simple enough that it can't generate any new errors, at least
292  * not before popping the error stack.
293  *
294  * Note: an ereport(FATAL) will not be caught by this construct; control will
295  * exit straight through proc_exit(). Therefore, do NOT put any cleanup
296  * of non-process-local resources into the error recovery section, at least
297  * not without taking thought for what will happen during ereport(FATAL).
298  * The PG_ENSURE_ERROR_CLEANUP macros provided by storage/ipc.h may be
299  * helpful in such cases.
300  *
301  * Note: if a local variable of the function containing PG_TRY is modified
302  * in the PG_TRY section and used in the PG_CATCH section, that variable
303  * must be declared "volatile" for POSIX compliance. This is not mere
304  * pedantry; we have seen bugs from compilers improperly optimizing code
305  * away when such a variable was not marked. Beware that gcc's -Wclobbered
306  * warnings are just about entirely useless for catching such oversights.
307  *----------
308  */
309 #define PG_TRY() \
310  do { \
311  sigjmp_buf *_save_exception_stack = PG_exception_stack; \
312  ErrorContextCallback *_save_context_stack = error_context_stack; \
313  sigjmp_buf _local_sigjmp_buf; \
314  bool _do_rethrow = false; \
315  if (sigsetjmp(_local_sigjmp_buf, 0) == 0) \
316  { \
317  PG_exception_stack = &_local_sigjmp_buf
318 
319 #define PG_CATCH() \
320  } \
321  else \
322  { \
323  PG_exception_stack = _save_exception_stack; \
324  error_context_stack = _save_context_stack
325 
326 #define PG_FINALLY() \
327  } \
328  else \
329  _do_rethrow = true; \
330  { \
331  PG_exception_stack = _save_exception_stack; \
332  error_context_stack = _save_context_stack
333 
334 #define PG_END_TRY() \
335  } \
336  if (_do_rethrow) \
337  PG_RE_THROW(); \
338  PG_exception_stack = _save_exception_stack; \
339  error_context_stack = _save_context_stack; \
340  } while (0)
341 
342 /*
343  * Some compilers understand pg_attribute_noreturn(); for other compilers,
344  * insert pg_unreachable() so that the compiler gets the point.
345  */
346 #ifdef HAVE_PG_ATTRIBUTE_NORETURN
347 #define PG_RE_THROW() \
348  pg_re_throw()
349 #else
350 #define PG_RE_THROW() \
351  (pg_re_throw(), pg_unreachable())
352 #endif
353 
354 extern PGDLLIMPORT sigjmp_buf *PG_exception_stack;
355 
356 
357 /* Stuff that error handlers might want to use */
358 
359 /*
360  * ErrorData holds the data accumulated during any one ereport() cycle.
361  * Any non-NULL pointers must point to palloc'd data.
362  * (The const pointers are an exception; we assume they point at non-freeable
363  * constant strings.)
364  */
365 typedef struct ErrorData
366 {
367  int elevel; /* error level */
368  bool output_to_server; /* will report to server log? */
369  bool output_to_client; /* will report to client? */
370  bool show_funcname; /* true to force funcname inclusion */
371  bool hide_stmt; /* true to prevent STATEMENT: inclusion */
372  bool hide_ctx; /* true to prevent CONTEXT: inclusion */
373  const char *filename; /* __FILE__ of ereport() call */
374  int lineno; /* __LINE__ of ereport() call */
375  const char *funcname; /* __func__ of ereport() call */
376  const char *domain; /* message domain */
377  const char *context_domain; /* message domain for context message */
378  int sqlerrcode; /* encoded ERRSTATE */
379  char *message; /* primary error message (translated) */
380  char *detail; /* detail error message */
381  char *detail_log; /* detail error message for server log only */
382  char *hint; /* hint message */
383  char *context; /* context message */
384  char *backtrace; /* backtrace */
385  const char *message_id; /* primary message's id (original string) */
386  char *schema_name; /* name of schema */
387  char *table_name; /* name of table */
388  char *column_name; /* name of column */
389  char *datatype_name; /* name of datatype */
390  char *constraint_name; /* name of constraint */
391  int cursorpos; /* cursor index into query string */
392  int internalpos; /* cursor index into internalquery */
393  char *internalquery; /* text of internally-generated query */
394  int saved_errno; /* errno at entry */
395 
396  /* context containing associated non-constant strings */
398 } ErrorData;
399 
400 extern void EmitErrorReport(void);
401 extern ErrorData *CopyErrorData(void);
402 extern void FreeErrorData(ErrorData *edata);
403 extern void FlushErrorState(void);
404 extern void ReThrowError(ErrorData *edata) pg_attribute_noreturn();
405 extern void ThrowErrorData(ErrorData *edata);
406 extern void pg_re_throw(void) pg_attribute_noreturn();
407 
408 extern char *GetErrorContextStack(void);
409 
410 /* Hook for intercepting messages before they are sent to the server log */
411 typedef void (*emit_log_hook_type) (ErrorData *edata);
413 
414 
415 /* GUC-configurable parameters */
416 
417 typedef enum
418 {
419  PGERROR_TERSE, /* single-line error messages */
420  PGERROR_DEFAULT, /* recommended style */
421  PGERROR_VERBOSE /* all the facts, ma'am */
423 
424 extern int Log_error_verbosity;
425 extern char *Log_line_prefix;
426 extern int Log_destination;
427 extern char *Log_destination_string;
428 extern bool syslog_sequence_numbers;
429 extern bool syslog_split_messages;
430 
431 /* Log destination bitmap */
432 #define LOG_DESTINATION_STDERR 1
433 #define LOG_DESTINATION_SYSLOG 2
434 #define LOG_DESTINATION_EVENTLOG 4
435 #define LOG_DESTINATION_CSVLOG 8
436 
437 /* Other exported functions */
438 extern void DebugFileOpen(void);
439 extern char *unpack_sql_state(int sql_state);
440 extern bool in_error_recursion_trouble(void);
441 
442 #ifdef HAVE_SYSLOG
443 extern void set_syslog_parameters(const char *ident, int facility);
444 #endif
445 
446 /*
447  * Write errors to stderr (or by equal means when stderr is
448  * not available). Used before ereport/elog can be used
449  * safely (memory context, GUC load etc)
450  */
451 extern void write_stderr(const char *fmt,...) pg_attribute_printf(1, 2);
452 
453 #endif /* ELOG_H */
char * schema_name
Definition: elog.h:386
#define pg_attribute_noreturn()
Definition: c.h:167
bool hide_stmt
Definition: elog.h:371
int errbacktrace(void)
Definition: elog.c:924
#define pg_attribute_cold
Definition: c.h:225
void pre_format_elog_string(int errnumber, const char *domain)
Definition: elog.c:1459
int errcode_for_file_access(void)
Definition: elog.c:714
int errposition(int cursorpos)
Definition: elog.c:1277
char * format_elog_string(const char *fmt,...) pg_attribute_printf(1
int sqlerrcode
Definition: elog.h:378
const char * funcname
Definition: elog.h:375
void ReThrowError(ErrorData *edata) pg_attribute_noreturn()
Definition: elog.c:1730
ErrorData * CopyErrorData(void)
Definition: elog.c:1552
int int int pg_attribute_printf(2, 4)
char * Log_line_prefix
Definition: elog.c:109
int lineno
Definition: elog.h:374
PGDLLIMPORT sigjmp_buf * PG_exception_stack
Definition: elog.c:94
char * internalquery
Definition: elog.h:393
int int errmsg_internal(const char *fmt,...) pg_attribute_printf(1
int int errhidestmt(bool hide_stmt)
Definition: elog.c:1220
void FreeErrorData(ErrorData *edata)
Definition: elog.c:1608
char struct ErrorContextCallback ErrorContextCallback
void errfinish(const char *filename, int lineno, const char *funcname)
Definition: elog.c:507
struct ErrorContextCallback * previous
Definition: elog.h:242
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:1313
int cursorpos
Definition: elog.h:391
const char * context_domain
Definition: elog.h:377
int errhidecontext(bool hide_ctx)
Definition: elog.c:1239
bool syslog_sequence_numbers
Definition: elog.c:112
char * GetErrorContextStack(void)
Definition: elog.c:1847
const char * filename
Definition: elog.h:373
char * detail_log
Definition: elog.h:381
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:785
int set_errcontext_domain(const char *domain)
Definition: elog.c:1200
static void callback(struct sockaddr *addr, struct sockaddr *mask, void *unused)
Definition: test_ifaddrs.c:48
int geterrcode(void)
Definition: elog.c:1392
int geterrposition(void)
Definition: elog.c:1409
int internalerrquery(const char *query)
Definition: elog.c:1313
char * table_name
Definition: elog.h:387
pg_attribute_cold bool errstart_cold(int elevel, const char *domain)
Definition: elog.c:318
bool output_to_server
Definition: elog.h:368
int internalpos
Definition: elog.h:392
int saved_errno
Definition: elog.h:394
bool hide_ctx
Definition: elog.h:372
void ThrowErrorData(ErrorData *edata)
Definition: elog.c:1671
const char * ident
Definition: memnodes.h:89
int internalerrposition(int cursorpos)
Definition: elog.c:1293
char * backtrace
Definition: elog.h:384
char * datatype_name
Definition: elog.h:389
int elevel
Definition: elog.h:367
static int elevel
Definition: vacuumlazy.c:333
char * detail
Definition: elog.h:380
void EmitErrorReport(void)
Definition: elog.c:1501
int int errdetail_internal(const char *fmt,...) pg_attribute_printf(1
PGDLLIMPORT emit_log_hook_type emit_log_hook
Definition: elog.c:105
const char * message_id
Definition: elog.h:385
int Log_destination
Definition: elog.c:110
bool show_funcname
Definition: elog.h:370
int errmsg(const char *fmt,...) pg_attribute_printf(1
void(* emit_log_hook_type)(ErrorData *edata)
Definition: elog.h:411
bool message_level_is_interesting(int elevel)
Definition: elog.c:264
char * column_name
Definition: elog.h:388
int err_generic_string(int field, const char *str)
Definition: elog.c:1343
int getinternalerrposition(void)
Definition: elog.c:1426
PGErrorVerbosity
Definition: elog.h:417
bool errstart(int elevel, const char *domain)
Definition: elog.c:334
char * hint
Definition: elog.h:382
int errcontext_msg(const char *fmt,...) pg_attribute_printf(1
char * context
Definition: elog.h:383
struct MemoryContextData * assoc_context
Definition: elog.h:397
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:91
bool in_error_recursion_trouble(void)
Definition: elog.c:285
void pg_re_throw(void) pg_attribute_noreturn()
Definition: elog.c:1791
void write_stderr(const char *fmt,...) pg_attribute_printf(1
void * arg
bool syslog_split_messages
Definition: elog.c:113
int errfunction(const char *funcname)
Definition: elog.c:1260
void FlushErrorState(void)
Definition: elog.c:1646
int errdetail(const char *fmt,...) pg_attribute_printf(1
int Log_error_verbosity
Definition: elog.c:108
const char * domain
Definition: elog.h:376
char * constraint_name
Definition: elog.h:390
char * Log_destination_string
Definition: elog.c:111
char * unpack_sql_state(int sql_state)
Definition: elog.c:2965
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:369
char * message
Definition: elog.h:379
void DebugFileOpen(void)
Definition: elog.c:1914
PGDLLIMPORT ErrorContextCallback * error_context_stack
Definition: elog.c:92
struct ErrorData ErrorData
int errcode(int sqlerrcode)
Definition: elog.c:691