1 | /* |
---|
2 | * Revision Control Information |
---|
3 | * |
---|
4 | * $Id: safe_mem.c,v 1.1.1.1 2008-11-14 20:40:10 hhkim Exp $ |
---|
5 | * |
---|
6 | */ |
---|
7 | /* LINTLIBRARY */ |
---|
8 | |
---|
9 | #include "util.h" |
---|
10 | |
---|
11 | /* |
---|
12 | * These are interface routines to be placed between a program and the |
---|
13 | * system memory allocator. |
---|
14 | * |
---|
15 | * It forces well-defined semantics for several 'borderline' cases: |
---|
16 | * |
---|
17 | * malloc() of a 0 size object is guaranteed to return something |
---|
18 | * which is not 0, and can safely be freed (but not dereferenced) |
---|
19 | * free() accepts (silently) an 0 pointer |
---|
20 | * realloc of a 0 pointer is allowed, and is equiv. to malloc() |
---|
21 | * For the IBM/PC it forces no object > 64K; note that the size argument |
---|
22 | * to malloc/realloc is a 'long' to catch this condition |
---|
23 | * |
---|
24 | * The function pointer MMoutOfMemory() contains a vector to handle a |
---|
25 | * 'out-of-memory' error (which, by default, points at a simple wrap-up |
---|
26 | * and exit routine). |
---|
27 | */ |
---|
28 | |
---|
29 | void (*MMoutOfMemory)(unsigned long) = MMout_of_memory; |
---|
30 | |
---|
31 | |
---|
32 | /* MMout_of_memory -- out of memory for lazy people, flush and exit */ |
---|
33 | void |
---|
34 | MMout_of_memory(unsigned long size) |
---|
35 | { |
---|
36 | (void) fflush(stdout); |
---|
37 | (void) fprintf(stderr, "\nout of memory allocating %lu bytes\n", size); |
---|
38 | exit(1); |
---|
39 | } |
---|
40 | |
---|
41 | |
---|
42 | void * |
---|
43 | MMalloc(unsigned long size) |
---|
44 | { |
---|
45 | void *p; |
---|
46 | |
---|
47 | #ifdef IBMPC |
---|
48 | if (size > 65000L) { |
---|
49 | if (MMoutOfMemory != (void (*)(unsigned long)) 0) (*MMoutOfMemory)(size); |
---|
50 | return NIL(void); |
---|
51 | } |
---|
52 | #endif |
---|
53 | if (size == 0) size = sizeof(long); |
---|
54 | if ((p = malloc(size)) == NIL(void)) { |
---|
55 | if (MMoutOfMemory != (void (*)(unsigned long)) 0) (*MMoutOfMemory)(size); |
---|
56 | return NIL(void); |
---|
57 | } |
---|
58 | return p; |
---|
59 | } |
---|
60 | |
---|
61 | |
---|
62 | void * |
---|
63 | MMrealloc(void *obj, unsigned long size) |
---|
64 | { |
---|
65 | void *p; |
---|
66 | |
---|
67 | #ifdef IBMPC |
---|
68 | if (size > 65000L) { |
---|
69 | if (MMoutOfMemory != (void (*)(unsigned long)) 0) (*MMoutOfMemory)(size); |
---|
70 | return NIL(void); |
---|
71 | } |
---|
72 | #endif |
---|
73 | if (obj == NIL(void)) return MMalloc(size); |
---|
74 | if (size <= 0) size = sizeof(long); |
---|
75 | if ((p = realloc(obj, size)) == NIL(void)) { |
---|
76 | if (MMoutOfMemory != (void (*)(unsigned long)) 0) (*MMoutOfMemory)(size); |
---|
77 | return NIL(void); |
---|
78 | } |
---|
79 | return p; |
---|
80 | } |
---|
81 | |
---|
82 | |
---|
83 | void |
---|
84 | MMfree(void *obj) |
---|
85 | { |
---|
86 | if (obj != 0) { |
---|
87 | free(obj); |
---|
88 | } |
---|
89 | } |
---|