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Diffstat (limited to 'source4/lib/ldb/common/ldb_alloc.c')
-rw-r--r-- | source4/lib/ldb/common/ldb_alloc.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/source4/lib/ldb/common/ldb_alloc.c b/source4/lib/ldb/common/ldb_alloc.c new file mode 100644 index 0000000000..667759e832 --- /dev/null +++ b/source4/lib/ldb/common/ldb_alloc.c @@ -0,0 +1,174 @@ +/* + ldb database library + + Copyright (C) Andrew Tridgell 2004 + + ** NOTE! The following LGPL license applies to the ldb + ** library. This does NOT imply that all of Samba is released + ** under the LGPL + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with this library; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ + +/* + * Name: ldb + * + * Component: ldb alloc + * + * Description: functions for memory allocation + * + * Author: Andrew Tridgell + */ + +#include "includes.h" + + +/* + this allows the user to choose their own allocation function +*/ +int ldb_set_alloc(struct ldb_context *ldb, + void *(*alloc)(void *context, void *ptr, size_t size), + void *context) +{ + ldb->alloc_ops.alloc = alloc; + ldb->alloc_ops.context = context; + return 0; +} + +/* + this is the default memory allocation function +*/ +static void *ldb_default_alloc(void *context, void *ptr, size_t size) +{ + /* by setting LDB_ALLOC_OFS to non-zero the test suite can + catch any places where we incorrectly use the libc alloc + funcitons directly */ +#define LDB_ALLOC_OFS 4 + /* we don't assume a modern realloc function */ + if (ptr == NULL) { + ptr = malloc(size+LDB_ALLOC_OFS); + if (ptr) return ((char *)ptr)+LDB_ALLOC_OFS; + return NULL; + } + if (size == 0) { + free(((char *)ptr)-LDB_ALLOC_OFS); + return NULL; + } + ptr = realloc(((char *)ptr)-LDB_ALLOC_OFS, size+LDB_ALLOC_OFS); + if (ptr) { + return ((char *)ptr)+LDB_ALLOC_OFS; + } + return NULL; +} + +/* + all memory allocation goes via this function +*/ +void *ldb_realloc(struct ldb_context *ldb, void *ptr, size_t size) +{ + if (!ldb->alloc_ops.alloc) { + ldb_set_alloc(ldb, ldb_default_alloc, NULL); + } + return ldb->alloc_ops.alloc(ldb->alloc_ops.context, ptr, size); +} + +void *ldb_malloc(struct ldb_context *ldb, size_t size) +{ + return ldb_realloc(ldb, NULL, size); +} + +void ldb_free(struct ldb_context *ldb, void *ptr) +{ + if (ptr != NULL) { + ldb_realloc(ldb, ptr, 0); + } +} + +void *ldb_strndup(struct ldb_context *ldb, const char *str, size_t maxlen) +{ + size_t len = strnlen(str, maxlen); + void *ret; + ret = ldb_realloc(ldb, NULL, len+1); + if (ret) { + memcpy(ret, str, len); + ((char *)ret)[len] = 0; + } + return ret; +} + +void *ldb_strdup(struct ldb_context *ldb, const char *str) +{ + size_t len = strlen(str); + void *ret; + ret = ldb_realloc(ldb, NULL, len+1); + if (ret) { + memcpy(ret, str, len+1); + } + return ret; +} + +/* + a ldb wrapper for asprintf(), using ldb_malloc() +*/ +int ldb_asprintf(struct ldb_context *ldb, char **strp, const char *fmt, ...) +{ + int len, len2; + va_list ap; + + *strp = NULL; + + va_start(ap, fmt); + len = vsnprintf(NULL, 0, fmt, ap); + va_end(ap); + if (len < 0) { + return len; + } + + *strp = ldb_malloc(ldb, len+1); + if (! *strp) { + return -1; + } + + va_start(ap, fmt); + len2 = vsnprintf(*strp, len+1, fmt, ap); + va_end(ap); + + if (len2 != len) { + /* buggy (or non-C99) vsnprintf function */ + ldb_free(ldb, *strp); + return -1; + } + + return len; +} + +/* + realloc an array, checking for integer overflow in the array size +*/ +void *ldb_realloc_array(struct ldb_context *ldb, + void *ptr, size_t el_size, unsigned count) +{ +#define MAX_MALLOC_SIZE 0x7fffffff + + if (count == 0 || + count >= MAX_MALLOC_SIZE/el_size) { + return NULL; + } + if (!ptr) { + return ldb_malloc(ldb, el_size * count); + } + return ldb_realloc(ldb, ptr, el_size * count); +} + |