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Diffstat (limited to 'static/netbsd/man3/sqlite3_malloc.3')
| -rw-r--r-- | static/netbsd/man3/sqlite3_malloc.3 | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/static/netbsd/man3/sqlite3_malloc.3 b/static/netbsd/man3/sqlite3_malloc.3 new file mode 100644 index 00000000..0a5fd072 --- /dev/null +++ b/static/netbsd/man3/sqlite3_malloc.3 @@ -0,0 +1,128 @@ +.Dd January 24, 2024 +.Dt SQLITE3_MALLOC 3 +.Os +.Sh NAME +.Nm sqlite3_malloc , +.Nm sqlite3_malloc64 , +.Nm sqlite3_realloc , +.Nm sqlite3_realloc64 , +.Nm sqlite3_free , +.Nm sqlite3_msize +.Nd memory allocation subsystem +.Sh SYNOPSIS +.In sqlite3.h +.Ft void * +.Fo sqlite3_malloc +.Fa "int" +.Fc +.Ft void * +.Fo sqlite3_malloc64 +.Fa "sqlite3_uint64" +.Fc +.Ft void * +.Fo sqlite3_realloc +.Fa "void*" +.Fa "int" +.Fc +.Ft void * +.Fo sqlite3_realloc64 +.Fa "void*" +.Fa "sqlite3_uint64" +.Fc +.Ft void +.Fo sqlite3_free +.Fa "void*" +.Fc +.Ft sqlite3_uint64 +.Fo sqlite3_msize +.Fa "void*" +.Fc +.Sh DESCRIPTION +The SQLite core uses these three routines for all of its own internal +memory allocation needs. +"Core" in the previous sentence does not include operating-system specific +VFS implementation. +The Windows VFS uses native malloc() and free() for some operations. +.Pp +The sqlite3_malloc() routine returns a pointer to a block of memory +at least N bytes in length, where N is the parameter. +If sqlite3_malloc() is unable to obtain sufficient free memory, it +returns a NULL pointer. +If the parameter N to sqlite3_malloc() is zero or negative then sqlite3_malloc() +returns a NULL pointer. +.Pp +The sqlite3_malloc64(N) routine works just like sqlite3_malloc(N) except +that N is an unsigned 64-bit integer instead of a signed 32-bit integer. +.Pp +Calling sqlite3_free() with a pointer previously returned by sqlite3_malloc() +or sqlite3_realloc() releases that memory so that it might be reused. +The sqlite3_free() routine is a no-op if is called with a NULL pointer. +Passing a NULL pointer to sqlite3_free() is harmless. +After being freed, memory should neither be read nor written. +Even reading previously freed memory might result in a segmentation +fault or other severe error. +Memory corruption, a segmentation fault, or other severe error might +result if sqlite3_free() is called with a non-NULL pointer that was +not obtained from sqlite3_malloc() or sqlite3_realloc(). +.Pp +The sqlite3_realloc(X,N) interface attempts to resize a prior memory +allocation X to be at least N bytes. +If the X parameter to sqlite3_realloc(X,N) is a NULL pointer then its +behavior is identical to calling sqlite3_malloc(N). +If the N parameter to sqlite3_realloc(X,N) is zero or negative then +the behavior is exactly the same as calling sqlite3_free(X). +sqlite3_realloc(X,N) returns a pointer to a memory allocation of at +least N bytes in size or NULL if insufficient memory is available. +If M is the size of the prior allocation, then min(N,M) bytes of the +prior allocation are copied into the beginning of buffer returned by +sqlite3_realloc(X,N) and the prior allocation is freed. +If sqlite3_realloc(X,N) returns NULL and N is positive, then the prior +allocation is not freed. +.Pp +The sqlite3_realloc64(X,N) interfaces works the same as sqlite3_realloc(X,N) +except that N is a 64-bit unsigned integer instead of a 32-bit signed +integer. +.Pp +If X is a memory allocation previously obtained from sqlite3_malloc(), +sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then +sqlite3_msize(X) returns the size of that memory allocation in bytes. +The value returned by sqlite3_msize(X) might be larger than the number +of bytes requested when X was allocated. +If X is a NULL pointer then sqlite3_msize(X) returns zero. +If X points to something that is not the beginning of memory allocation, +or if it points to a formerly valid memory allocation that has now +been freed, then the behavior of sqlite3_msize(X) is undefined and +possibly harmful. +.Pp +The memory returned by sqlite3_malloc(), sqlite3_realloc(), sqlite3_malloc64(), +and sqlite3_realloc64() is always aligned to at least an 8 byte boundary, +or to a 4 byte boundary if the SQLITE_4_BYTE_ALIGNED_MALLOC +compile-time option is used. +.Pp +The pointer arguments to +.Fn sqlite3_free +and +.Fn sqlite3_realloc +must be either NULL or else pointers obtained from a prior invocation +of +.Fn sqlite3_malloc +or +.Fn sqlite3_realloc +that have not yet been released. +.Pp +The application must not read or write any part of a block of memory +after it has been released using +.Fn sqlite3_free +or +.Fn sqlite3_realloc . +.Sh IMPLEMENTATION NOTES +These declarations were extracted from the +interface documentation at line 2993. +.Bd -literal +SQLITE_API void *sqlite3_malloc(int); +SQLITE_API void *sqlite3_malloc64(sqlite3_uint64); +SQLITE_API void *sqlite3_realloc(void*, int); +SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); +SQLITE_API void sqlite3_free(void*); +SQLITE_API sqlite3_uint64 sqlite3_msize(void*); +.Ed |