diff options
Diffstat (limited to 'libmariadb/libmariadb/ma_array.c')
| -rw-r--r-- | libmariadb/libmariadb/ma_array.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/libmariadb/libmariadb/ma_array.c b/libmariadb/libmariadb/ma_array.c new file mode 100644 index 00000000..d067aa4a --- /dev/null +++ b/libmariadb/libmariadb/ma_array.c @@ -0,0 +1,172 @@ +/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB + 2016 MariaDB Corporation AB + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with this library; if not, write to the Free + Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, + MA 02111-1301, USA */ + +/* Handling of arrays that can grow dynamically. */ + +#undef SAFEMALLOC /* Problems with threads */ + +#include <ma_global.h> +#include <ma_sys.h> +#include "ma_string.h" +#include <memory.h> + +/* + Initiate array and alloc space for init_alloc elements. Array is usable + even if space allocation failed +*/ + +my_bool ma_init_dynamic_array(DYNAMIC_ARRAY *array, uint element_size, + uint init_alloc, uint alloc_increment CALLER_INFO_PROTO) +{ + if (!alloc_increment) + { + alloc_increment=max((8192-MALLOC_OVERHEAD)/element_size,16); + if (init_alloc > 8 && alloc_increment > init_alloc * 2) + alloc_increment=init_alloc*2; + } + + if (!init_alloc) + init_alloc=alloc_increment; + array->elements=0; + array->max_element=init_alloc; + array->alloc_increment=alloc_increment; + array->size_of_element=element_size; + if (!(array->buffer=(char*) malloc(element_size*init_alloc))) + { + array->max_element=0; + return(TRUE); + } + return(FALSE); +} + + +my_bool ma_insert_dynamic(DYNAMIC_ARRAY *array, void *element) +{ + void *buffer; + if (array->elements == array->max_element) + { /* Call only when necessary */ + if (!(buffer=ma_alloc_dynamic(array))) + return TRUE; + } + else + { + buffer=array->buffer+(array->elements * array->size_of_element); + array->elements++; + } + memcpy(buffer,element,(size_t) array->size_of_element); + return FALSE; +} + + + /* Alloc room for one element */ + +unsigned char *ma_alloc_dynamic(DYNAMIC_ARRAY *array) +{ + if (array->elements == array->max_element) + { + char *new_ptr; + if (!(new_ptr=(char*) realloc(array->buffer,(array->max_element+ + array->alloc_increment)* + array->size_of_element))) + return 0; + array->buffer=new_ptr; + array->max_element+=array->alloc_increment; + } + return (unsigned char *)array->buffer+(array->elements++ * array->size_of_element); +} + + + /* remove last element from array and return it */ + +unsigned char *ma_pop_dynamic(DYNAMIC_ARRAY *array) +{ + if (array->elements) + return (unsigned char *)array->buffer+(--array->elements * array->size_of_element); + return 0; +} + + +my_bool ma_set_dynamic(DYNAMIC_ARRAY *array, void * element, uint idx) +{ + if (idx >= array->elements) + { + if (idx >= array->max_element) + { + uint size; + char *new_ptr; + size=(idx+array->alloc_increment)/array->alloc_increment; + size*= array->alloc_increment; + if (!(new_ptr=(char*) realloc(array->buffer,size* + array->size_of_element))) + return TRUE; + array->buffer=new_ptr; + array->max_element=size; + } + memset((array->buffer+array->elements*array->size_of_element), 0, + (idx - array->elements)*array->size_of_element); + array->elements=idx+1; + } + memcpy(array->buffer+(idx * array->size_of_element),element, + (size_t) array->size_of_element); + return FALSE; +} + + +void ma_get_dynamic(DYNAMIC_ARRAY *array, void * element, uint idx) +{ + if (idx >= array->elements) + { + memset(element, 0, array->size_of_element); + return; + } + memcpy(element,array->buffer+idx*array->size_of_element, + (size_t) array->size_of_element); +} + + +void ma_delete_dynamic(DYNAMIC_ARRAY *array) +{ + if (array->buffer) + { + free(array->buffer); + array->buffer=0; + array->elements=array->max_element=0; + } +} + + +void ma_delete_dynamic_element(DYNAMIC_ARRAY *array, uint idx) +{ + char *ptr=array->buffer+array->size_of_element*idx; + array->elements--; + memmove(ptr,ptr+array->size_of_element, + (array->elements-idx)*array->size_of_element); +} + + +void ma_freeze_size(DYNAMIC_ARRAY *array) +{ + uint elements=max(array->elements,1); + + if (array->buffer && array->max_element != elements) + { + array->buffer=(char*) realloc(array->buffer, + elements*array->size_of_element); + array->max_element=elements; + } +} |