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. */
57 #define BSS_PAD_SIZE 0x1000
59 #define BSS_PAD_SIZE 0
62 /* To prevent zero-initialized variables from being placed into the bss
63 section, use non-zero values to represent an uninitialized state. */
64 #define UNINIT_PTR ((void *) 0xF0A0F0A0)
65 #define UNINIT_LONG (0xF0A0F0A0L)
67 static void get_section_info (int a_out, char* a_name);
68 static void copy_executable_and_dump_data_section (int a_out, int a_new);
69 static void dup_file_area(int a_out, int a_new, long size);
71 static void write_int_to_bss(int a_out, int a_new, void* va, void* newval);
74 /* Cached info about the .data section in the executable. */
75 void* data_start_va = UNINIT_PTR;
76 unsigned long data_size = UNINIT_LONG;
78 /* Cached info about the .bss section in the executable. */
79 void* bss_start = UNINIT_PTR;
80 unsigned long bss_size = UNINIT_LONG;
81 int sections_reversed = 0;
84 SCNHDR f_data, f_bss, f_text, f_nextdata;
86 #define PERROR(arg) perror(arg);exit(-1)
87 #define CHECK_AOUT_POS(a) \
88 if (lseek(a_out, 0, SEEK_CUR) != a) \
90 printf("we are at %lx, should be at %lx\n", \
91 lseek(a_out, 0, SEEK_CUR), a); \
96 unexec (char *out_name, char *in_name, void *start_data,
97 void * d1, void * d2);
98 /* Dump out .data and .bss sections into a new executable. */
99 void unexec (char *out_name, char *in_name, void *start_data,
100 void * d1, void * d2)
102 /* ugly nt hack - should be in lisp */
103 int a_new, a_out = -1;
104 char new_name[MAX_PATH], a_name[MAX_PATH];
107 /* Make sure that the input and output filenames have the
108 ".exe" extension...patch them up if they don't. */
109 strcpy (a_name, in_name);
110 ptr = a_name + strlen (a_name) - 4;
111 if (strcmp (ptr, ".exe"))
112 strcat (a_name, ".exe");
114 strcpy (new_name, out_name);
115 ptr = new_name + strlen (new_name) - 4;
116 if (strcmp (ptr, ".exe"))
117 strcat (new_name, ".exe");
119 /* We need to round off our heap to NT's allocation unit (64KB). */
120 /* round_heap (get_allocation_unit ()); */
122 if (a_name && (a_out = open (a_name, O_RDONLY | OPEN_BINARY)) < 0)
127 if ((a_new = open (new_name, O_WRONLY | O_TRUNC | O_CREAT | OPEN_BINARY,
133 /* Get the interesting section info, like start and size of .bss... */
134 get_section_info (a_out, a_name);
136 copy_executable_and_dump_data_section (a_out, a_new);
142 /* Flip through the executable and cache the info necessary for dumping. */
143 static void get_section_info (int a_out, char* a_name)
146 /* From lastfile.c */
147 extern char my_edata[];
149 if (read (a_out, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr))
154 if (f_hdr.e_magic != DOSMAGIC)
156 PERROR("unknown exe header");
159 /* Check the NT header signature ... */
160 if (f_hdr.nt_signature != NT_SIGNATURE)
162 PERROR("invalid nt header");
165 /* Flip through the sections for .data and .bss ... */
166 if (f_hdr.f_opthdr > 0)
168 if (read (a_out, &f_ohdr, AOUTSZ) != AOUTSZ)
173 /* Loop through .data & .bss section headers, copying them in.
174 With newer lds these are reversed so we have to cope with both */
175 lseek (a_out, sizeof (f_hdr) + f_hdr.f_opthdr, 0);
177 if (read (a_out, &f_text, sizeof (f_text)) != sizeof (f_text)
179 strcmp (f_text.s_name, ".text"))
181 PERROR ("no .text section");
184 /* The .bss section. */
185 if (read (a_out, &f_bss, sizeof (f_bss)) != sizeof (f_bss)
187 (strcmp (f_bss.s_name, ".bss") && strcmp (f_bss.s_name, ".data")))
189 PERROR ("no .bss / .data section");
192 /* check for reversed .bss and .data */
193 if (!strcmp(f_bss.s_name, ".data"))
195 printf(".data and .bss reversed\n");
196 sections_reversed = 1;
197 memcpy(&f_data, &f_bss, sizeof(f_bss));
200 /* The .data section. */
201 if (!sections_reversed)
203 if (read (a_out, &f_data, sizeof (f_data)) != sizeof (f_data)
205 strcmp (f_data.s_name, ".data"))
207 PERROR ("no .data section");
212 if (read (a_out, &f_bss, sizeof (f_bss)) != sizeof (f_bss)
214 strcmp (f_bss.s_name, ".bss"))
216 PERROR ("no .bss section");
220 bss_start = (void *) ((char*)f_ohdr.ImageBase + f_bss.s_vaddr);
221 bss_size = (unsigned long)((char*)&my_ebss-(char*)bss_start);
223 /* must keep bss data that we want to be blank as blank */
224 printf("found bss - keeping %lx of %lx bytes\n", bss_size, f_ohdr.bsize);
226 /* The .data section. */
227 data_start_va = (void *) ((char*)f_ohdr.ImageBase + f_data.s_vaddr);
229 /* We want to only write Emacs data back to the executable,
230 not any of the library data (if library data is included,
231 then a dumped Emacs won't run on system versions other
232 than the one Emacs was dumped on). */
233 data_size = (unsigned long)my_edata - (unsigned long)data_start_va;
234 printf("found data - keeping %lx of %lx bytes\n", data_size, f_ohdr.dsize);
236 /* The following data section - often .idata */
237 if (read (a_out, &f_nextdata, sizeof (f_nextdata)) != sizeof (f_nextdata)
239 strcmp (&f_nextdata.s_name[2], "data"))
241 PERROR ("no other data section");
245 /* The dump routines. */
248 copy_executable_and_dump_data_section (int a_out, int a_new)
251 unsigned long new_data_size, new_bss_size,
252 bss_padding, file_sz_change, data_padding=0,
253 f_data_s_vaddr = f_data.s_vaddr,
254 f_data_s_scnptr = f_data.s_scnptr,
255 f_bss_s_vaddr = f_bss.s_vaddr,
256 f_nextdata_s_scnptr = f_nextdata.s_scnptr;
260 extern int static_heap_dumped;
262 /* calculate new sizes:
264 f_ohdr.dsize is the total initialized data size on disk which is
265 f_data.s_size + f_idata.s_size.
267 f_ohdr.data_start is the base addres of all data and so should
270 *.s_vaddr is the virtual address of the start of the section
271 *normalized from f_ohdr.ImageBase.
273 *.s_paddr appears to be the number of bytes in the section
274 *actually used (whereas *.s_size is aligned).
276 bsize is now 0 since subsumed into .data
277 dsize is dsize + (f_data.s_vaddr - f_bss.s_vaddr)
278 f_data.s_vaddr is f_bss.s_vaddr
279 f_data.s_size is new dsize maybe.
280 what about s_paddr & s_scnptr? */
282 /* this is the amount the file increases in size */
283 if (!sections_reversed)
285 new_bss_size = f_data.s_vaddr - f_bss.s_vaddr;
290 new_bss_size = f_nextdata.s_vaddr - f_bss.s_vaddr;
291 data_padding = (f_bss.s_vaddr - f_data.s_vaddr) - f_data.s_size;
294 file_sz_change=(new_bss_size + data_padding) - BSS_PAD_SIZE;
295 new_data_size=f_ohdr.dsize + file_sz_change;
297 if (!sections_reversed)
299 f_data.s_vaddr = f_bss.s_vaddr;
301 f_data.s_paddr += file_sz_change;
303 if (f_data.s_size + f_nextdata.s_size != f_ohdr.dsize)
305 printf("section size doesn't tally with dsize %lx != %lx\n",
306 f_data.s_size + f_nextdata.s_size, f_ohdr.dsize);
309 f_data.s_size += file_sz_change;
310 lseek (a_new, 0, SEEK_SET);
311 /* write file header */
312 f_hdr.f_symptr += file_sz_change;
317 printf("writing file header\n");
318 if (write(a_new, &f_hdr, sizeof(f_hdr)) != sizeof(f_hdr))
320 PERROR("failed to write file header");
322 /* write optional header fixing dsize & bsize*/
323 printf("writing optional header\n");
324 printf("new data size is %lx, >= %lx\n", new_data_size,
325 f_ohdr.dsize + f_ohdr.bsize);
326 if (new_data_size < f_ohdr.dsize + f_ohdr.bsize )
328 PERROR("new data size is < approx");
330 f_ohdr.dsize=new_data_size;
331 f_ohdr.bsize=BSS_PAD_SIZE;
332 if (write(a_new, &f_ohdr, sizeof(f_ohdr)) != sizeof(f_ohdr))
334 PERROR("failed to write optional header");
336 /* write text as is */
337 printf("writing text header (unchanged)\n");
339 if (write(a_new, &f_text, sizeof(f_text)) != sizeof(f_text))
341 PERROR("failed to write text header");
344 /* Write small bss section. */
345 if (!sections_reversed)
347 f_bss.s_size = BSS_PAD_SIZE;
348 f_bss.s_paddr = BSS_PAD_SIZE;
349 f_bss.s_vaddr = f_data.s_vaddr - BSS_PAD_SIZE;
350 if (write(a_new, &f_bss, sizeof(f_bss)) != sizeof(f_bss))
352 PERROR("failed to write bss header");
356 /* write new data header */
357 printf("writing .data header\n");
359 if (write(a_new, &f_data, sizeof(f_data)) != sizeof(f_data))
361 PERROR("failed to write data header");
364 /* Write small bss section. */
365 if (sections_reversed)
367 f_bss.s_size = BSS_PAD_SIZE;
368 f_bss.s_paddr = BSS_PAD_SIZE;
369 f_bss.s_vaddr = f_nextdata.s_vaddr - BSS_PAD_SIZE;
370 if (write(a_new, &f_bss, sizeof(f_bss)) != sizeof(f_bss))
372 PERROR("failed to write bss header");
376 printf("writing following data header\n");
377 f_nextdata.s_scnptr += file_sz_change;
378 if (f_nextdata.s_lnnoptr != 0) f_nextdata.s_lnnoptr += file_sz_change;
379 if (f_nextdata.s_relptr != 0) f_nextdata.s_relptr += file_sz_change;
380 if (write(a_new, &f_nextdata, sizeof(f_nextdata)) != sizeof(f_nextdata))
382 PERROR("failed to write nextdata header");
385 /* copy other section headers adjusting the file offset */
386 for (i=0; i<(f_hdr.f_nscns-3); i++)
388 if (read (a_out, §ion, sizeof (section)) != sizeof (section))
390 PERROR ("no .data section");
393 section.s_scnptr += file_sz_change;
394 if (section.s_lnnoptr != 0) section.s_lnnoptr += file_sz_change;
395 if (section.s_relptr != 0) section.s_relptr += file_sz_change;
397 if (write(a_new, §ion, sizeof(section)) != sizeof(section))
399 PERROR("failed to write data header");
403 /* dump bss to maintain offsets */
404 memset(&f_bss, 0, sizeof(f_bss));
405 if (write(a_new, &f_bss, sizeof(f_bss)) != sizeof(f_bss))
407 PERROR("failed to write bss header");
410 size=lseek(a_new, 0, SEEK_CUR);
411 CHECK_AOUT_POS(size);
413 /* copy eveything else until start of data */
414 size = f_data_s_scnptr - lseek (a_out, 0, SEEK_CUR);
416 printf ("copying executable up to data section ... %lx bytes\n",
418 dup_file_area(a_out, a_new, size);
420 CHECK_AOUT_POS(f_data_s_scnptr);
422 if (!sections_reversed)
424 /* dump bss + padding between sections, sans small bss pad */
425 printf ("dumping .bss into executable... %lx bytes\n", bss_size);
426 if (write(a_new, bss_start, bss_size) != (int)bss_size)
428 PERROR("failed to write bss section");
431 /* pad, needs to be zero */
432 bss_padding = (new_bss_size - bss_size) - BSS_PAD_SIZE;
435 PERROR("padded .bss too small");
437 printf ("padding .bss ... %lx bytes\n", bss_padding);
438 empty_space = malloc(bss_padding);
439 memset(empty_space, 0, bss_padding);
440 if (write(a_new, empty_space, bss_padding) != (int)bss_padding)
442 PERROR("failed to write bss section");
447 /* tell dumped version not to free pure heap */
448 static_heap_dumped = 1;
449 /* Get a pointer to the raw data in our address space. */
450 printf ("dumping .data section... %lx bytes\n", data_size);
451 if (write(a_new, data_start_va, data_size) != (int)data_size)
453 PERROR("failed to write data section");
455 /* were going to use free again ... */
456 static_heap_dumped = 0;
458 size = lseek(a_out, f_data_s_scnptr + data_size, SEEK_SET);
460 if (!sections_reversed)
462 size = f_nextdata_s_scnptr - size;
463 dup_file_area(a_out, a_new, size);
467 /* need to pad to bss with data in file */
468 printf ("padding .data ... %lx bytes\n", data_padding);
469 size = (f_bss_s_vaddr - f_data_s_vaddr) - data_size;
470 dup_file_area(a_out, a_new, size);
472 /* dump bss + padding between sections */
473 printf ("dumping .bss into executable... %lx bytes\n", bss_size);
474 if (write(a_new, bss_start, bss_size) != (int)bss_size)
476 PERROR("failed to write bss section");
479 /* pad, needs to be zero */
480 bss_padding = (new_bss_size - bss_size) - BSS_PAD_SIZE;
483 PERROR("padded .bss too small");
485 printf ("padding .bss ... %lx bytes\n", bss_padding);
486 empty_space = malloc(bss_padding);
487 memset(empty_space, 0, bss_padding);
488 if (write(a_new, empty_space, bss_padding) != (int)bss_padding)
490 PERROR("failed to write bss section");
493 if (lseek(a_new, 0, SEEK_CUR) != f_nextdata.s_scnptr)
495 printf("at %lx should be at %lx\n",
496 lseek(a_new, 0, SEEK_CUR),
497 f_nextdata.s_scnptr);
498 PERROR("file positioning error\n");
500 lseek(a_out, f_nextdata_s_scnptr, SEEK_SET);
503 CHECK_AOUT_POS(f_nextdata_s_scnptr);
505 /* now dump - nextdata don't need to do this cygwin ds is in .data! */
506 printf ("dumping following data section... %lx bytes\n", f_nextdata.s_size);
508 dup_file_area(a_out,a_new,f_nextdata.s_size);
510 /* write rest of file */
511 printf ("writing rest of file\n");
512 size = lseek(a_out, 0, SEEK_END);
513 size = size - (f_nextdata_s_scnptr + f_nextdata.s_size); /* length remaining in a_out */
514 lseek(a_out, f_nextdata_s_scnptr + f_nextdata.s_size, SEEK_SET);
516 dup_file_area(a_out, a_new, size);
520 * copy from aout to anew
522 static void dup_file_area(int a_out, int a_new, long size)
526 for (; size > 0; size -= sizeof (page))
528 n = size > sizeof (page) ? sizeof (page) : size;
529 if (read (a_out, page, n) != n || write (a_new, page, n) != n)
531 PERROR ("dump_out()");
537 static void write_int_to_bss(int a_out, int a_new, void* va, void* newval)
541 cpos = lseek(a_new, 0, SEEK_CUR);
542 if (va < bss_start || va > bss_start + f_data.s_size)
544 PERROR("address not in data space\n");
546 lseek(a_new, f_data.s_scnptr + ((unsigned long)va -
547 (unsigned long)bss_start), SEEK_SET);
548 if (write(a_new, newval, sizeof(int)) != (int)sizeof(int))
550 PERROR("failed to write int value");
552 lseek(a_new, cpos, SEEK_SET);
556 #endif /* HAVE_A_OUT_H */