1 /* unexec for GNU Emacs on Cygwin32.
2 Copyright (C) 1994, 1998 Free Software Foundation, Inc.
4 This file is part of XEmacs.
6 XEmacs is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by the
8 Free Software Foundation; either version 2, or (at your option) any
11 XEmacs is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with XEmacs; see the file COPYING. If not, write to the Free
18 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
23 /* This is a complete rewrite, some code snarfed from unexnt.c and
24 unexec.c, Andy Piper (andy@xemacs.org) 13-1-98 */
33 #define DONT_ENCAPSULATE /* filenames are external in unex*.c */
36 #define PERROR(arg) perror(arg);exit(-1)
39 unexec (char *, char *, void *, void *, void *)
41 PERROR("cannot unexec() a.out.h not installed");
50 #define ALLOC_UNIT 0xFFFF
51 #define ALLOC_MASK ~((unsigned long)(ALLOC_UNIT))
52 #define ALIGN_ALLOC(addr) \
53 ((((unsigned long)addr) + ALLOC_UNIT) & ALLOC_MASK)
54 /* Note that all sections must be aligned on a 0x1000 boundary so
55 this is the minimum size that our dummy bss can be. */
56 #define BSS_PAD_SIZE 0x1000
58 /* To prevent zero-initialized variables from being placed into the bss
59 section, use non-zero values to represent an uninitialized state. */
60 #define UNINIT_PTR ((void *) 0xF0A0F0A0)
61 #define UNINIT_LONG (0xF0A0F0A0L)
63 static void get_section_info (int a_out, char* a_name);
64 static void copy_executable_and_dump_data_section (int a_out, int a_new);
65 static void dup_file_area(int a_out, int a_new, long size);
67 static void write_int_to_bss(int a_out, int a_new, void* va, void* newval);
70 /* Cached info about the .data section in the executable. */
71 void* data_start_va = UNINIT_PTR;
72 unsigned long data_size = UNINIT_LONG;
74 /* Cached info about the .bss section in the executable. */
75 void* bss_start = UNINIT_PTR;
76 unsigned long bss_size = UNINIT_LONG;
77 int sections_reversed = 0;
80 SCNHDR f_data, f_bss, f_text, f_nextdata;
82 #define PERROR(arg) perror(arg);exit(-1)
83 #define CHECK_AOUT_POS(a) \
84 if (lseek(a_out, 0, SEEK_CUR) != a) \
86 printf("we are at %lx, should be at %lx\n", \
87 lseek(a_out, 0, SEEK_CUR), a); \
92 unexec (char *out_name, char *in_name, void *start_data,
93 void * d1, void * d2);
94 /* Dump out .data and .bss sections into a new executable. */
95 void unexec (char *out_name, char *in_name, void *start_data,
98 /* ugly nt hack - should be in lisp */
99 int a_new, a_out = -1;
100 char new_name[MAX_PATH], a_name[MAX_PATH];
103 /* Make sure that the input and output filenames have the
104 ".exe" extension...patch them up if they don't. */
105 strcpy (a_name, in_name);
106 ptr = a_name + strlen (a_name) - 4;
107 if (strcmp (ptr, ".exe"))
108 strcat (a_name, ".exe");
110 strcpy (new_name, out_name);
111 ptr = new_name + strlen (new_name) - 4;
112 if (strcmp (ptr, ".exe"))
113 strcat (new_name, ".exe");
115 /* We need to round off our heap to NT's allocation unit (64KB). */
116 /* round_heap (get_allocation_unit ()); */
118 if (a_name && (a_out = open (a_name, O_RDONLY | OPEN_BINARY)) < 0)
123 if ((a_new = open (new_name, O_WRONLY | O_TRUNC | O_CREAT | OPEN_BINARY,
129 /* Get the interesting section info, like start and size of .bss... */
130 get_section_info (a_out, a_name);
132 copy_executable_and_dump_data_section (a_out, a_new);
138 /* Flip through the executable and cache the info necessary for dumping. */
139 static void get_section_info (int a_out, char* a_name)
142 /* From lastfile.c */
143 extern char my_edata[];
145 if (read (a_out, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr))
150 if (f_hdr.e_magic != DOSMAGIC)
152 PERROR("unknown exe header");
155 /* Check the NT header signature ... */
156 if (f_hdr.nt_signature != NT_SIGNATURE)
158 PERROR("invalid nt header");
161 /* Flip through the sections for .data and .bss ... */
162 if (f_hdr.f_opthdr > 0)
164 if (read (a_out, &f_ohdr, AOUTSZ) != AOUTSZ)
169 /* Loop through .data & .bss section headers, copying them in.
170 With newer lds these are reversed so we have to cope with both */
171 lseek (a_out, sizeof (f_hdr) + f_hdr.f_opthdr, 0);
173 if (read (a_out, &f_text, sizeof (f_text)) != sizeof (f_text)
175 strcmp (f_text.s_name, ".text"))
177 PERROR ("no .text section");
180 /* The .bss section. */
181 if (read (a_out, &f_bss, sizeof (f_bss)) != sizeof (f_bss)
183 (strcmp (f_bss.s_name, ".bss") && strcmp (f_bss.s_name, ".data")))
185 PERROR ("no .bss / .data section");
188 /* check for reversed .bss and .data */
189 if (!strcmp(f_bss.s_name, ".data"))
191 printf(".data and .bss reversed\n");
192 sections_reversed = 1;
193 memcpy(&f_data, &f_bss, sizeof(f_bss));
196 /* The .data section. */
197 if (!sections_reversed)
199 if (read (a_out, &f_data, sizeof (f_data)) != sizeof (f_data)
201 strcmp (f_data.s_name, ".data"))
203 PERROR ("no .data section");
208 if (read (a_out, &f_bss, sizeof (f_bss)) != sizeof (f_bss)
210 strcmp (f_bss.s_name, ".bss"))
212 PERROR ("no .bss section");
216 bss_start = (void *) ((char*)f_ohdr.ImageBase + f_bss.s_vaddr);
217 bss_size = (unsigned long)((char*)&my_ebss-(char*)bss_start);
219 /* must keep bss data that we want to be blank as blank */
220 printf("found bss - keeping %lx of %lx bytes\n", bss_size, f_ohdr.bsize);
222 /* The .data section. */
223 data_start_va = (void *) ((char*)f_ohdr.ImageBase + f_data.s_vaddr);
225 /* We want to only write Emacs data back to the executable,
226 not any of the library data (if library data is included,
227 then a dumped Emacs won't run on system versions other
228 than the one Emacs was dumped on). */
229 data_size = (unsigned long)my_edata - (unsigned long)data_start_va;
230 printf("found data - keeping %lx of %lx bytes\n", data_size, f_ohdr.dsize);
232 /* The following data section - often .idata */
233 if (read (a_out, &f_nextdata, sizeof (f_nextdata)) != sizeof (f_nextdata)
235 strcmp (&f_nextdata.s_name[2], "data"))
237 PERROR ("no other data section");
241 /* The dump routines. */
244 copy_executable_and_dump_data_section (int a_out, int a_new)
247 unsigned long new_data_size, new_bss_size,
248 bss_padding, file_sz_change, data_padding=0,
249 f_data_s_vaddr = f_data.s_vaddr,
250 f_data_s_scnptr = f_data.s_scnptr,
251 f_bss_s_vaddr = f_bss.s_vaddr,
252 f_nextdata_s_scnptr = f_nextdata.s_scnptr;
256 extern int static_heap_dumped;
258 /* calculate new sizes:
260 f_ohdr.dsize is the total initialized data size on disk which is
261 f_data.s_size + f_idata.s_size.
263 f_ohdr.data_start is the base addres of all data and so should
266 *.s_vaddr is the virtual address of the start of the section
267 *normalized from f_ohdr.ImageBase.
269 *.s_paddr appears to be the number of bytes in the section
270 *actually used (whereas *.s_size is aligned).
272 bsize is now 0 since subsumed into .data
273 dsize is dsize + (f_data.s_vaddr - f_bss.s_vaddr)
274 f_data.s_vaddr is f_bss.s_vaddr
275 f_data.s_size is new dsize maybe.
276 what about s_paddr & s_scnptr? */
278 /* this is the amount the file increases in size */
279 if (!sections_reversed)
281 new_bss_size = f_data.s_vaddr - f_bss.s_vaddr;
286 new_bss_size = f_nextdata.s_vaddr - f_bss.s_vaddr;
287 data_padding = (f_bss.s_vaddr - f_data.s_vaddr) - f_data.s_size;
290 file_sz_change=(new_bss_size + data_padding) - BSS_PAD_SIZE;
291 new_data_size=f_ohdr.dsize + file_sz_change;
293 if (!sections_reversed)
295 f_data.s_vaddr = f_bss.s_vaddr;
297 f_data.s_paddr += file_sz_change;
299 if (f_data.s_size + f_nextdata.s_size != f_ohdr.dsize)
301 printf("section size doesn't tally with dsize %lx != %lx\n",
302 f_data.s_size + f_nextdata.s_size, f_ohdr.dsize);
305 f_data.s_size += file_sz_change;
306 lseek (a_new, 0, SEEK_SET);
307 /* write file header */
308 f_hdr.f_symptr += file_sz_change;
310 printf("writing file header\n");
311 if (write(a_new, &f_hdr, sizeof(f_hdr)) != sizeof(f_hdr))
313 PERROR("failed to write file header");
315 /* write optional header fixing dsize & bsize*/
316 printf("writing optional header\n");
317 printf("new data size is %lx, >= %lx\n", new_data_size,
318 f_ohdr.dsize + f_ohdr.bsize);
319 if (new_data_size < f_ohdr.dsize + f_ohdr.bsize )
321 PERROR("new data size is < approx");
323 f_ohdr.dsize=new_data_size;
324 f_ohdr.bsize=BSS_PAD_SIZE;
325 if (write(a_new, &f_ohdr, sizeof(f_ohdr)) != sizeof(f_ohdr))
327 PERROR("failed to write optional header");
329 /* write text as is */
330 printf("writing text header (unchanged)\n");
332 if (write(a_new, &f_text, sizeof(f_text)) != sizeof(f_text))
334 PERROR("failed to write text header");
337 /* Write small bss section. */
338 if (!sections_reversed)
340 f_bss.s_size = BSS_PAD_SIZE;
341 f_bss.s_paddr = BSS_PAD_SIZE;
342 f_bss.s_vaddr = f_data.s_vaddr - BSS_PAD_SIZE;
343 if (write(a_new, &f_bss, sizeof(f_bss)) != sizeof(f_bss))
345 PERROR("failed to write bss header");
349 /* write new data header */
350 printf("writing .data header\n");
352 if (write(a_new, &f_data, sizeof(f_data)) != sizeof(f_data))
354 PERROR("failed to write data header");
357 /* Write small bss section. */
358 if (sections_reversed)
360 f_bss.s_size = BSS_PAD_SIZE;
361 f_bss.s_paddr = BSS_PAD_SIZE;
362 f_bss.s_vaddr = f_nextdata.s_vaddr - BSS_PAD_SIZE;
363 if (write(a_new, &f_bss, sizeof(f_bss)) != sizeof(f_bss))
365 PERROR("failed to write bss header");
369 printf("writing following data header\n");
370 f_nextdata.s_scnptr += file_sz_change;
371 if (f_nextdata.s_lnnoptr != 0) f_nextdata.s_lnnoptr += file_sz_change;
372 if (f_nextdata.s_relptr != 0) f_nextdata.s_relptr += file_sz_change;
373 if (write(a_new, &f_nextdata, sizeof(f_nextdata)) != sizeof(f_nextdata))
375 PERROR("failed to write nextdata header");
378 /* copy other section headers adjusting the file offset */
379 for (i=0; i<(f_hdr.f_nscns-3); i++)
381 if (read (a_out, §ion, sizeof (section)) != sizeof (section))
383 PERROR ("no .data section");
386 section.s_scnptr += file_sz_change;
387 if (section.s_lnnoptr != 0) section.s_lnnoptr += file_sz_change;
388 if (section.s_relptr != 0) section.s_relptr += file_sz_change;
390 if (write(a_new, §ion, sizeof(section)) != sizeof(section))
392 PERROR("failed to write data header");
396 size=lseek(a_new, 0, SEEK_CUR);
397 CHECK_AOUT_POS(size);
399 /* copy eveything else until start of data */
400 size = f_data_s_scnptr - lseek (a_out, 0, SEEK_CUR);
402 printf ("copying executable up to data section ... %lx bytes\n",
404 dup_file_area(a_out, a_new, size);
406 CHECK_AOUT_POS(f_data_s_scnptr);
408 if (!sections_reversed)
410 /* dump bss + padding between sections, sans small bss pad */
411 printf ("dumping .bss into executable... %lx bytes\n", bss_size);
412 if (write(a_new, bss_start, bss_size) != (int)bss_size)
414 PERROR("failed to write bss section");
417 /* pad, needs to be zero */
418 bss_padding = (new_bss_size - bss_size) - BSS_PAD_SIZE;
421 PERROR("padded .bss too small");
423 printf ("padding .bss ... %lx bytes\n", bss_padding);
424 empty_space = malloc(bss_padding);
425 memset(empty_space, 0, bss_padding);
426 if (write(a_new, empty_space, bss_padding) != (int)bss_padding)
428 PERROR("failed to write bss section");
433 /* tell dumped version not to free pure heap */
434 static_heap_dumped = 1;
435 /* Get a pointer to the raw data in our address space. */
436 printf ("dumping .data section... %lx bytes\n", data_size);
437 if (write(a_new, data_start_va, data_size) != (int)data_size)
439 PERROR("failed to write data section");
441 /* were going to use free again ... */
442 static_heap_dumped = 0;
444 size = lseek(a_out, f_data_s_scnptr + data_size, SEEK_SET);
446 if (!sections_reversed)
448 size = f_nextdata_s_scnptr - size;
449 dup_file_area(a_out, a_new, size);
453 /* need to pad to bss with data in file */
454 printf ("padding .data ... %lx bytes\n", data_padding);
455 size = (f_bss_s_vaddr - f_data_s_vaddr) - data_size;
456 dup_file_area(a_out, a_new, size);
458 /* dump bss + padding between sections */
459 printf ("dumping .bss into executable... %lx bytes\n", bss_size);
460 if (write(a_new, bss_start, bss_size) != (int)bss_size)
462 PERROR("failed to write bss section");
465 /* pad, needs to be zero */
466 bss_padding = (new_bss_size - bss_size) - BSS_PAD_SIZE;
469 PERROR("padded .bss too small");
471 printf ("padding .bss ... %lx bytes\n", bss_padding);
472 empty_space = malloc(bss_padding);
473 memset(empty_space, 0, bss_padding);
474 if (write(a_new, empty_space, bss_padding) != (int)bss_padding)
476 PERROR("failed to write bss section");
479 if (lseek(a_new, 0, SEEK_CUR) != f_nextdata.s_scnptr)
481 printf("at %lx should be at %lx\n",
482 lseek(a_new, 0, SEEK_CUR),
483 f_nextdata.s_scnptr);
484 PERROR("file positioning error\n");
486 lseek(a_out, f_nextdata_s_scnptr, SEEK_SET);
489 CHECK_AOUT_POS(f_nextdata_s_scnptr);
491 /* now dump - nextdata don't need to do this cygwin ds is in .data! */
492 printf ("dumping following data section... %lx bytes\n", f_nextdata.s_size);
494 dup_file_area(a_out,a_new,f_nextdata.s_size);
496 /* write rest of file */
497 printf ("writing rest of file\n");
498 size = lseek(a_out, 0, SEEK_END);
499 size = size - (f_nextdata_s_scnptr + f_nextdata.s_size); /* length remaining in a_out */
500 lseek(a_out, f_nextdata_s_scnptr + f_nextdata.s_size, SEEK_SET);
502 dup_file_area(a_out, a_new, size);
506 * copy from aout to anew
508 static void dup_file_area(int a_out, int a_new, long size)
512 for (; size > 0; size -= sizeof (page))
514 n = size > sizeof (page) ? sizeof (page) : size;
515 if (read (a_out, page, n) != n || write (a_new, page, n) != n)
517 PERROR ("dump_out()");
523 static void write_int_to_bss(int a_out, int a_new, void* va, void* newval)
527 cpos = lseek(a_new, 0, SEEK_CUR);
528 if (va < bss_start || va > bss_start + f_data.s_size)
530 PERROR("address not in data space\n");
532 lseek(a_new, f_data.s_scnptr + ((unsigned long)va -
533 (unsigned long)bss_start), SEEK_SET);
534 if (write(a_new, newval, sizeof(int)) != (int)sizeof(int))
536 PERROR("failed to write int value");
538 lseek(a_new, cpos, SEEK_SET);
542 #endif /* HAVE_A_OUT_H */