diff options
Diffstat (limited to 'db2/common/db_salloc.c')
| -rw-r--r-- | db2/common/db_salloc.c | 41 |
1 files changed, 26 insertions, 15 deletions
diff --git a/db2/common/db_salloc.c b/db2/common/db_salloc.c index f0202ddb90..0fa696bf7e 100644 --- a/db2/common/db_salloc.c +++ b/db2/common/db_salloc.c @@ -1,21 +1,21 @@ /*- * See the file LICENSE for redistribution information. * - * Copyright (c) 1996, 1997 + * Copyright (c) 1996, 1997, 1998 * Sleepycat Software. All rights reserved. */ #include "config.h" #ifndef lint -static const char sccsid[] = "@(#)db_salloc.c 10.6 (Sleepycat) 7/5/97"; +static const char sccsid[] = "@(#)db_salloc.c 10.13 (Sleepycat) 5/10/98"; #endif /* not lint */ #ifndef NO_SYSTEM_INCLUDES #include <sys/types.h> #include <errno.h> -#include <stdio.h> +#include <string.h> #endif #include "db_int.h" @@ -109,11 +109,13 @@ __db_shalloc(p, len, align, retp) *(void **)retp = rp; +#define SHALLOC_FRAGMENT 32 /* - * If there are at least 32 bytes of additional memory, divide - * the chunk into two chunks. + * If there are at least SHALLOC_FRAGMENT additional bytes of + * memory, divide the chunk into two chunks. */ - if ((u_int8_t *)rp >= (u_int8_t *)&elp->links + 32) { + if ((u_int8_t *)rp >= + (u_int8_t *)&elp->links + SHALLOC_FRAGMENT) { sp = rp; *--sp = elp->len - ((u_int8_t *)rp - (u_int8_t *)&elp->links); @@ -136,7 +138,7 @@ __db_shalloc(p, len, align, retp) return (0); } - /* Nothing found large enough; need to figure out how to grow region. */ + /* Nothing found large enough; need to grow the region. */ return (ENOMEM); } @@ -159,12 +161,18 @@ __db_shalloc_free(regionp, ptr) * Step back over flagged length fields to find the beginning of * the object and its real size. */ - for (sp = (size_t *)ptr; sp[-1] == ILLEGAL_SIZE; --sp); + for (sp = (size_t *)ptr; sp[-1] == ILLEGAL_SIZE; --sp) + ; ptr = sp; newp = (struct __data *)((u_int8_t *)ptr - sizeof(size_t)); free_size = newp->len; + /* Trash the returned memory. */ +#ifdef DIAGNOSTIC + memset(ptr, 0xff, free_size); +#endif + /* * Walk the list, looking for where this entry goes. * @@ -177,7 +185,8 @@ __db_shalloc_free(regionp, ptr) hp = (struct __head *)regionp; for (elp = SH_LIST_FIRST(hp, __data), lastp = NULL; elp != NULL && (void *)elp < (void *)ptr; - lastp = elp, elp = SH_LIST_NEXT(elp, links, __data)); + lastp = elp, elp = SH_LIST_NEXT(elp, links, __data)) + ; /* * Elp is either NULL (we reached the end of the list), or the slot @@ -259,32 +268,34 @@ __db_shsizeof(ptr) * Step back over flagged length fields to find the beginning of * the object and its real size. */ - for (sp = (size_t *)ptr; sp[-1] == ILLEGAL_SIZE; --sp); + for (sp = (size_t *)ptr; sp[-1] == ILLEGAL_SIZE; --sp) + ; elp = (struct __data *)((u_int8_t *)sp - sizeof(size_t)); return (elp->len); } -#ifdef DEBUG /* * __db_shalloc_dump -- * - * PUBLIC: void __db_shalloc_dump __P((FILE *, void *)); + * PUBLIC: void __db_shalloc_dump __P((void *, FILE *)); */ void -__db_shalloc_dump(fp, addr) - FILE *fp; +__db_shalloc_dump(addr, fp) void *addr; + FILE *fp; { struct __data *elp; + /* Make it easy to call from the debugger. */ if (fp == NULL) fp = stderr; + fprintf(fp, "%s\nMemory free list\n", DB_LINE); + for (elp = SH_LIST_FIRST((struct __head *)addr, __data); elp != NULL; elp = SH_LIST_NEXT(elp, links, __data)) fprintf(fp, "%#lx: %lu\t", (u_long)elp, (u_long)elp->len); fprintf(fp, "\n"); } -#endif |