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[xemacs-hg @ 2002-05-23 11:46:08 by ben] fix for raymond toy's crash, alloca crashes, some recover-session improvements files.el: Recover-session improvements: Only show session files where some files can actually be recovered, and show in chronological order. subr.el, menubar-items.el: As promised to rms, the functionality in truncate-string-with-continuation-dots has been merged into truncate-string-to-width. Change callers in menubar-items.el. select.el: Document some of these funs better. Fix problem where we were doing own-clipboard twice. Makefile.in.in: Add alloca.o. Ensure that alloca.s doesn't compile into alloca.o, but allocax.o (not that it's currently used or anything.) EmacsFrame.c, abbrev.c, alloc.c, alloca.c, callint.c, callproc.c, config.h.in, device-msw.c, device-x.c, dired.c, doc.c, editfns.c, emacs.c, emodules.c, eval.c, event-Xt.c, event-msw.c, event-stream.c, file-coding.c, fileio.c, filelock.c, fns.c, glyphs-gtk.c, glyphs-msw.c, glyphs-x.c, gui-x.c, input-method-xlib.c, intl-win32.c, lisp.h, lread.c, menubar-gtk.c, menubar-msw.c, menubar.c, mule-wnnfns.c, nt.c, objects-msw.c, process-nt.c, realpath.c, redisplay-gtk.c, redisplay-output.c, redisplay-x.c, redisplay.c, search.c, select-msw.c, sysdep.c, syswindows.h, text.c, text.h, ui-byhand.c: Fix Raymond Toy's crash. Repeat to self: 2^21 - 1 is NOT the same as (2 << 21) - 1. Fix crashes due to excessive alloca(). replace alloca() with ALLOCA(), which calls the C alloca() [which uses xmalloc()] when the size is too big. Insert in various places calls to try to flush the C alloca() stored info if there is any. Add MALLOC_OR_ALLOCA(), for places that expect to be alloca()ing large blocks. This xmalloc()s when too large and records an unwind-protect to free -- relying on the caller to unbind_to() elsewhere in the function. Use it in concat(). Use MALLOC instead of ALLOCA in select-msw.c. xemacs.mak: Add alloca.o.
author ben
date Thu, 23 May 2002 11:46:46 +0000
parents 3078fd1074e8
children 184461bc8de4
comparison
equal deleted inserted replaced
850:f915ad7befaf 851:e7ee5f8bde58
24 /* Synched up with: FSF 19.30. */ 24 /* Synched up with: FSF 19.30. */
25 25
26 /* Authorship: 26 /* Authorship:
27 27
28 FSF: A long time ago. 28 FSF: A long time ago.
29 Very few changes for XEmacs. 29 Some cleanups for XEmacs.
30 */ 30 */
31 31
32 #ifdef HAVE_CONFIG_H 32 #ifdef HAVE_CONFIG_H
33 #include <config.h> 33 #include <config.h>
34 #endif 34 #endif
35 35
36 /* XEmacs: If compiling with GCC 2, this file is theoretically not needed.
37 However, alloca() is broken under GCC 2 on many machines: you
38 cannot put a call to alloca() as part of an argument to a function.
39 */
40 /* If someone has defined alloca as a macro,
41 there must be some other way alloca is supposed to work. */
42 /* XEmacs sometimes uses the C alloca even when a builtin alloca is available,
43 because it's safer. */
44 #if defined (EMACS_WANTS_C_ALLOCA) || (!defined (alloca) && (!defined (__GNUC__) || __GNUC__ < 2))
45
46 #ifdef emacs 36 #ifdef emacs
47 #ifdef static 37 #include "lisp.h"
48 /* actually, only want this if static is defined as "" 38 #endif
49 -- this is for usg, in which emacs must undefine static
50 in order to make unexec workable
51 */
52 #ifndef STACK_DIRECTION
53 you
54 lose
55 -- must know STACK_DIRECTION at compile-time
56 #endif /* STACK_DIRECTION undefined */
57 #endif /* static */
58 #endif /* emacs */
59 39
60 /* If your stack is a linked list of frames, you have to 40 /* If your stack is a linked list of frames, you have to
61 provide an "address metric" ADDRESS_FUNCTION macro. */ 41 provide an "address metric" ADDRESS_FUNCTION macro. */
62 42
63 #if defined (CRAY) && defined (CRAY_STACKSEG_END) 43 #if defined (CRAY) && defined (CRAY_STACKSEG_END)
65 #define ADDRESS_FUNCTION(arg) (char *) i00afunc (&(arg)) 45 #define ADDRESS_FUNCTION(arg) (char *) i00afunc (&(arg))
66 #else 46 #else
67 #define ADDRESS_FUNCTION(arg) &(arg) 47 #define ADDRESS_FUNCTION(arg) &(arg)
68 #endif 48 #endif
69 49
70 #ifdef __STDC__ /* XEmacs change */
71 typedef void *pointer; 50 typedef void *pointer;
72 #else
73 typedef char *pointer;
74 #endif
75
76 /* XEmacs: With ERROR_CHECK_MALLOC defined, there is no xfree -- it's
77 a macro that does some stuff to try and trap invalid frees,
78 and then calls xfree_1 to actually do the work. */
79
80 #ifdef emacs
81 # ifdef ERROR_CHECK_MALLOC
82 void xfree_1 (pointer);
83 # define xfree xfree_1
84 # else
85 void xfree (pointer);
86 # endif
87 #endif
88 51
89 #ifndef NULL 52 #ifndef NULL
90 #define NULL 0 53 #define NULL 0
91 #endif
92
93 /* Different portions of Emacs need to call different versions of
94 malloc. The Emacs executable needs alloca to call xmalloc, because
95 ordinary malloc isn't protected from input signals. On the other
96 hand, the utilities in lib-src need alloca to call malloc; some of
97 them are very simple, and don't have an xmalloc routine.
98
99 Non-Emacs programs expect this to call use xmalloc.
100
101 Callers below should use malloc. */
102
103 #ifdef emacs
104 #define malloc xmalloc
105 #endif
106 #ifndef WIN32_NATIVE
107 extern pointer malloc ();
108 #else
109 extern void *malloc();
110 #endif 54 #endif
111 55
112 /* Define STACK_DIRECTION if you know the direction of stack 56 /* Define STACK_DIRECTION if you know the direction of stack
113 growth for your system; otherwise it will be automatically 57 growth for your system; otherwise it will be automatically
114 deduced at run-time. 58 deduced at run-time.
159 (b) keep track of stack depth. 103 (b) keep track of stack depth.
160 104
161 It is very important that sizeof(header) agree with malloc 105 It is very important that sizeof(header) agree with malloc
162 alignment chunk size. The following default should work okay. */ 106 alignment chunk size. The following default should work okay. */
163 107
164 #ifndef ALIGN_SIZE 108 #ifndef ALIGNMENT_SIZE
165 #define ALIGN_SIZE sizeof(double) 109 #define ALIGNMENT_SIZE sizeof(double)
166 #endif 110 #endif
167 111
168 typedef union hdr 112 typedef union hdr
169 { 113 {
170 char align[ALIGN_SIZE]; /* To force sizeof(header). */ 114 char align[ALIGNMENT_SIZE]; /* To force sizeof(header). */
171 struct 115 struct
172 { 116 {
173 union hdr *next; /* For chaining headers. */ 117 union hdr *next; /* For chaining headers. */
174 char *deep; /* For stack depth measure. */ 118 char *deep; /* For stack depth measure. */
175 } h; 119 } h;
183 was supposed to be taken from the current stack frame of the 127 was supposed to be taken from the current stack frame of the
184 caller, but that method cannot be made to work for some 128 caller, but that method cannot be made to work for some
185 implementations of C, for example under Gould's UTX/32. */ 129 implementations of C, for example under Gould's UTX/32. */
186 130
187 pointer 131 pointer
188 #ifdef EMACS_WANTS_C_ALLOCA 132 xemacs_c_alloca (unsigned int size)
189 c_alloca (size)
190 #else
191 alloca (size)
192 #endif
193 unsigned size;
194 { 133 {
195 auto char probe; /* Probes stack depth: */ 134 auto char probe; /* Probes stack depth: */
196 register char *depth = ADDRESS_FUNCTION (probe); 135 register char *depth = ADDRESS_FUNCTION (probe);
197 136
198 #if STACK_DIRECTION == 0 137 #if STACK_DIRECTION == 0
210 if ((STACK_DIR > 0 && hp->h.deep > depth) 149 if ((STACK_DIR > 0 && hp->h.deep > depth)
211 || (STACK_DIR < 0 && hp->h.deep < depth)) 150 || (STACK_DIR < 0 && hp->h.deep < depth))
212 { 151 {
213 register header *np = hp->h.next; 152 register header *np = hp->h.next;
214 153
215 free ((pointer) hp); /* Collect garbage. */ 154 #ifdef emacs
155 xfree (hp); /* Collect garbage. */
156 #else
157 free (hp); /* Collect garbage. */
158 #endif
216 159
217 hp = np; /* -> next header. */ 160 hp = np; /* -> next header. */
218 } 161 }
219 else 162 else
220 break; /* Rest are not deeper. */ 163 break; /* Rest are not deeper. */
221 164
222 last_alloca_header = hp; /* -> last valid storage. */ 165 last_alloca_header = hp; /* -> last valid storage. */
223 } 166 }
224 167
168 #ifdef emacs
169 need_to_check_c_alloca = size > 0 || last_alloca_header;
170 recompute_funcall_allocation_flag ();
171 #endif
172
225 if (size == 0) 173 if (size == 0)
226 return NULL; /* No allocation required. */ 174 return NULL; /* No allocation required. */
227 175
228 /* Allocate combined header + user data storage. */ 176 /* Allocate combined header + user data storage. */
229 177
230 { 178 {
179 #ifdef emacs
180 register pointer new = xmalloc (sizeof (header) + size);
181 #else
231 register pointer new = malloc (sizeof (header) + size); 182 register pointer new = malloc (sizeof (header) + size);
183 #endif
232 /* Address of header. */ 184 /* Address of header. */
233 185
234 ((header *) new)->h.next = last_alloca_header; 186 ((header *) new)->h.next = last_alloca_header;
235 ((header *) new)->h.deep = depth; 187 ((header *) new)->h.deep = depth;
236 188
507 return (result); 459 return (result);
508 } 460 }
509 461
510 #endif /* not CRAY2 */ 462 #endif /* not CRAY2 */
511 #endif /* CRAY */ 463 #endif /* CRAY */
512
513 #endif /* complicated expression at top of file */