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SQLite Requirement Matrix Details
mutex_alloc.html
Index Summary Markup Original
R-62139-20964-30258-06406-62558-17842-12310-23723 tcl slt th3 src
The sqlite3_mutex_alloc() routine allocates a new mutex and returns a pointer to it.
/* IMP: R-62139-20964 */
# EVIDENCE-OF: R-62139-20964 The sqlite3_mutex_alloc() routine allocates # a new mutex and returns a pointer to it.
R-35945-11759-33348-59186-12007-55771-30323-25128 tcl slt th3 src
The sqlite3_mutex_alloc() routine returns NULL if it is unable to allocate the requested mutex.
/* IMP: R-35945-11759 */
# EVIDENCE-OF: R-35945-11759 The sqlite3_mutex_alloc() routine returns # NULL if it is unable to allocate the requested mutex.
R-02445-31643-12462-38565-43200-47259-24553-56004 tcl slt th3 src
The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) cause sqlite3_mutex_alloc() to create a new mutex.
/* IMP: R-02445-31643 */
# EVIDENCE-OF: R-02445-31643 The first two constants (SQLITE_MUTEX_FAST # and SQLITE_MUTEX_RECURSIVE) cause sqlite3_mutex_alloc() to create a # new mutex.
R-31231-36717-57726-13439-19567-41766-26823-60811 tcl slt th3 src
The new mutex is recursive when SQLITE_MUTEX_RECURSIVE is used but not necessarily so when SQLITE_MUTEX_FAST is used.
/* IMP: R-31231-36717 */
# EVIDENCE-OF: R-31231-36717 The new mutex is recursive when # SQLITE_MUTEX_RECURSIVE is used but not necessarily so when # SQLITE_MUTEX_FAST is used.
R-15968-48708-39759-44208-63382-65413-21684-48201 tcl slt th3 src
The other allowed parameters to sqlite3_mutex_alloc() (anything other than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return a pointer to a static preexisting mutex.
/* IMP: R-15968-48708 */
# EVIDENCE-OF: R-15968-48708 The other allowed parameters to # sqlite3_mutex_alloc() (anything other than SQLITE_MUTEX_FAST and # SQLITE_MUTEX_RECURSIVE) each return a pointer to a static preexisting # mutex.
R-34489-53953-36029-13063-60538-08284-18396-26034 tcl slt th3 src
Nine static mutexes are used by the current version of SQLite.
/* IMP: R-34489-53953 */
# EVIDENCE-OF: R-34489-53953 Nine static mutexes are used by the current # version of SQLite.
R-22391-07186-37161-38876-45465-63159-33403-63078 tcl slt th3 src
Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() returns a different mutex on every call.
th3/cov1/mutex01.test:36 th3/cov1/mutex01.test:68
/* IMP: R-22391-07186 */
# EVIDENCE-OF: R-22391-07186 Note that if one of the dynamic mutex # parameters (SQLITE_MUTEX_FAST or SQLITE_MUTEX_RECURSIVE) is used then # sqlite3_mutex_alloc() returns a different mutex on every call.
R-10379-15557-17362-29530-27887-61401-49779-43037 tcl slt th3 src
For the static mutex types, the same mutex is returned on every call that has the same type number.
/* IMP: R-10379-15557 */
# EVIDENCE-OF: R-10379-15557 For the static mutex types, the same mutex # is returned on every call that has the same type number.
R-43589-15127-43886-39082-32655-09009-64323-07852 tcl slt th3 src
The sqlite3_mutex_free() routine deallocates a previously allocated dynamic mutex.
/* IMP: R-43589-15127 */
# EVIDENCE-OF: R-43589-15127 The sqlite3_mutex_free() routine # deallocates a previously allocated dynamic mutex.
R-14816-14138-45914-00386-55030-19688-47427-16370 tcl slt th3 src
The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt to enter a mutex.
/* IMP: R-14816-14138 */
# EVIDENCE-OF: R-14816-14138 The sqlite3_mutex_enter() and # sqlite3_mutex_try() routines attempt to enter a mutex.
R-60813-08986-02359-37993-40551-24945-25887-06253 tcl slt th3 src
If another thread is already within the mutex, sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return SQLITE_BUSY.
/* IMP: R-60813-08986 */
# EVIDENCE-OF: R-60813-08986 If another thread is already within the # mutex, sqlite3_mutex_enter() will block and sqlite3_mutex_try() will # return SQLITE_BUSY.
R-60364-48303-16474-64960-19278-15379-28844-42689 tcl slt th3 src
The sqlite3_mutex_try() interface returns SQLITE_OK upon successful entry.
/* IMP: R-60364-48303 */
# EVIDENCE-OF: R-60364-48303 The sqlite3_mutex_try() interface returns # SQLITE_OK upon successful entry.
R-07896-01909-17755-58747-61497-14681-53331-52466 tcl slt th3 src
Mutexes created using SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. In such cases, the mutex must be exited an equal number of times before another thread can enter.
/* IMP: R-07896-01909 */
# EVIDENCE-OF: R-07896-01909 Mutexes created using # SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same # thread. In such cases, the mutex must be exited an equal number of # times before another thread can enter.
R-20974-45876-55609-02198-26922-65375-59673-02037 tcl slt th3 src
Some systems (for example, Windows 95) do not support the operation implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() will always return SQLITE_BUSY. The SQLite core only ever uses sqlite3_mutex_try() as an optimization so this is acceptable behavior.
th3/th3mutex.c:167
/* IMP: R-20974-45876 */
# EVIDENCE-OF: R-20974-45876 Some systems (for example, Windows 95) do # not support the operation implemented by sqlite3_mutex_try(). On those # systems, sqlite3_mutex_try() will always return SQLITE_BUSY. The # SQLite core only ever uses sqlite3_mutex_try() as an optimization so # this is acceptable behavior.
R-39221-43493-49031-48260-11050-48204-23096-55403 tcl slt th3 src
The sqlite3_mutex_leave() routine exits a mutex that was previously entered by the same thread.
/* IMP: R-39221-43493 */
# EVIDENCE-OF: R-39221-43493 The sqlite3_mutex_leave() routine exits a # mutex that was previously entered by the same thread.
R-29989-03153-00644-12353-52386-44408-44979-16456 tcl slt th3 src
If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or sqlite3_mutex_leave() is a NULL pointer, then all three routines behave as no-ops.
th3/cov1/mutex01.test:79
/* IMP: R-29989-03153 */
# EVIDENCE-OF: R-29989-03153 If the argument to sqlite3_mutex_enter(), # sqlite3_mutex_try(), or sqlite3_mutex_leave() is a NULL pointer, then # all three routines behave as no-ops.