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 */
35 #define DONT_ENCAPSULATE /* filenames are external in unex*.c */
38 #define PERROR(arg) perror(arg);exit(-1)
40 #if !defined(HAVE_A_OUT_H) && !defined(WIN32_NATIVE)
41 unexec (char *, char *, void *, void *, void *)
43 PERROR("cannot unexec() a.out.h not installed");
52 #include <../../include/a.out.h>
57 #define ALLOC_UNIT 0xFFFF
58 #define ALLOC_MASK ~((unsigned long)(ALLOC_UNIT))
59 #define ALIGN_ALLOC(addr) \
60 ((((unsigned long)addr) + ALLOC_UNIT) & ALLOC_MASK)
61 /* Note that all sections must be aligned on a 0x1000 boundary so
62 this is the minimum size that our dummy bss can be. */
64 #define BSS_PAD_SIZE 0x1000
66 #define BSS_PAD_SIZE 0
69 /* To prevent zero-initialized variables from being placed into the bss
70 section, use non-zero values to represent an uninitialized state. */
71 #define UNINIT_PTR ((void *) 0xF0A0F0A0)
72 #define UNINIT_LONG (0xF0A0F0A0L)
74 static void get_section_info (int a_out, char* a_name);
75 static void copy_executable_and_dump_data_section (int a_out, int a_new);
76 static void dup_file_area(int a_out, int a_new, long size);
78 static void write_int_to_bss(int a_out, int a_new, void* va, void* newval);
81 /* Cached info about the .data section in the executable. */
82 void* data_start_va = UNINIT_PTR;
83 unsigned long data_size = UNINIT_LONG;
85 /* Cached info about the .bss section in the executable. */
86 void* bss_start = UNINIT_PTR;
87 unsigned long bss_size = UNINIT_LONG;
88 int sections_reversed = 0;
91 SCNHDR f_data, f_bss, f_text, f_nextdata;
93 #define PERROR(arg) perror(arg);exit(-1)
94 #define CHECK_AOUT_POS(a) \
95 if (lseek(a_out, 0, SEEK_CUR) != a) \
97 printf("we are at %lx, should be at %lx\n", \
98 lseek(a_out, 0, SEEK_CUR), a); \
102 /* Dump out .data and .bss sections into a new executable. */
104 unexec (char *out_name, char *in_name, uintptr_t start_data,
105 uintptr_t d1, uintptr_t d2)
107 /* ugly nt hack - should be in lisp */
108 int a_new, a_out = -1;
109 char new_name[MAX_PATH], a_name[MAX_PATH];
112 /* Make sure that the input and output filenames have the
113 ".exe" extension...patch them up if they don't. */
114 strcpy (a_name, in_name);
115 ptr = a_name + strlen (a_name) - 4;
116 if (strcmp (ptr, ".exe"))
117 strcat (a_name, ".exe");
119 strcpy (new_name, out_name);
120 ptr = new_name + strlen (new_name) - 4;
121 if (strcmp (ptr, ".exe"))
122 strcat (new_name, ".exe");
124 /* We need to round off our heap to NT's allocation unit (64KB). */
125 /* round_heap (get_allocation_unit ()); */
127 if (a_name && (a_out = open (a_name, O_RDONLY | OPEN_BINARY)) < 0)
132 if ((a_new = open (new_name, O_WRONLY | O_TRUNC | O_CREAT | OPEN_BINARY,
138 /* Get the interesting section info, like start and size of .bss... */
139 get_section_info (a_out, a_name);
141 copy_executable_and_dump_data_section (a_out, a_new);
148 /* Flip through the executable and cache the info necessary for dumping. */
149 static void get_section_info (int a_out, char* a_name)
151 extern char my_ebss[];
152 /* From lastfile.c */
153 extern char my_edata[];
155 if (read (a_out, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr))
160 if (f_hdr.e_magic != DOSMAGIC)
162 PERROR("unknown exe header");
165 /* Check the NT header signature ... */
166 if (f_hdr.nt_signature != NT_SIGNATURE)
168 PERROR("invalid nt header");
171 /* Flip through the sections for .data and .bss ... */
172 if (f_hdr.f_opthdr > 0)
174 if (read (a_out, &f_ohdr, AOUTSZ) != AOUTSZ)
179 /* Loop through .data & .bss section headers, copying them in.
180 With newer lds these are reversed so we have to cope with both */
181 lseek (a_out, sizeof (f_hdr) + f_hdr.f_opthdr, 0);
183 if (read (a_out, &f_text, sizeof (f_text)) != sizeof (f_text)
185 strcmp (f_text.s_name, ".text"))
187 PERROR ("no .text section");
190 /* The .bss section. */
191 if (read (a_out, &f_bss, sizeof (f_bss)) != sizeof (f_bss)
193 (strcmp (f_bss.s_name, ".bss") && strcmp (f_bss.s_name, ".data")))
195 PERROR ("no .bss / .data section");
198 /* check for reversed .bss and .data */
199 if (!strcmp(f_bss.s_name, ".data"))
201 printf(".data and .bss reversed\n");
202 sections_reversed = 1;
203 memcpy(&f_data, &f_bss, sizeof(f_bss));
206 /* The .data section. */
207 if (!sections_reversed)
209 if (read (a_out, &f_data, sizeof (f_data)) != sizeof (f_data)
211 strcmp (f_data.s_name, ".data"))
213 PERROR ("no .data section");
218 if (read (a_out, &f_bss, sizeof (f_bss)) != sizeof (f_bss)
220 strcmp (f_bss.s_name, ".bss"))
222 PERROR ("no .bss section");
226 bss_start = (void *) ((char*)f_ohdr.ImageBase + f_bss.s_vaddr);
227 bss_size = (unsigned long)((char*)&my_ebss-(char*)bss_start);
229 /* must keep bss data that we want to be blank as blank */
230 printf("found bss - keeping %lx of %lx bytes\n", bss_size, f_ohdr.bsize);
232 /* The .data section. */
233 data_start_va = (void *) ((char*)f_ohdr.ImageBase + f_data.s_vaddr);
235 /* We want to only write Emacs data back to the executable,
236 not any of the library data (if library data is included,
237 then a dumped Emacs won't run on system versions other
238 than the one Emacs was dumped on). */
239 data_size = (unsigned long)my_edata - (unsigned long)data_start_va;
240 printf("found data - keeping %lx of %lx bytes\n", data_size, f_ohdr.dsize);
242 /* The following data section - often .idata */
243 if (read (a_out, &f_nextdata, sizeof (f_nextdata)) != sizeof (f_nextdata)
245 strcmp (&f_nextdata.s_name[2], "data"))
247 PERROR ("no other data section");
251 /* The dump routines. */
254 copy_executable_and_dump_data_section (int a_out, int a_new)
257 unsigned long new_data_size, new_bss_size,
258 bss_padding, file_sz_change, data_padding=0,
259 f_data_s_vaddr = f_data.s_vaddr,
260 f_data_s_scnptr = f_data.s_scnptr,
261 f_bss_s_vaddr = f_bss.s_vaddr,
262 f_nextdata_s_scnptr = f_nextdata.s_scnptr;
266 extern int static_heap_dumped;
268 /* calculate new sizes:
270 f_ohdr.dsize is the total initialized data size on disk which is
271 f_data.s_size + f_idata.s_size.
273 f_ohdr.data_start is the base addres of all data and so should
276 *.s_vaddr is the virtual address of the start of the section
277 *normalized from f_ohdr.ImageBase.
279 *.s_paddr appears to be the number of bytes in the section
280 *actually used (whereas *.s_size is aligned).
282 bsize is now 0 since subsumed into .data
283 dsize is dsize + (f_data.s_vaddr - f_bss.s_vaddr)
284 f_data.s_vaddr is f_bss.s_vaddr
285 f_data.s_size is new dsize maybe.
286 what about s_paddr & s_scnptr? */
288 /* this is the amount the file increases in size */
289 if (!sections_reversed)
291 new_bss_size = f_data.s_vaddr - f_bss.s_vaddr;
296 new_bss_size = f_nextdata.s_vaddr - f_bss.s_vaddr;
297 data_padding = (f_bss.s_vaddr - f_data.s_vaddr) - f_data.s_size;
300 if ((new_bss_size - bss_size) < BSS_PAD_SIZE)
302 PERROR (".bss free space too small");
305 file_sz_change=(new_bss_size + data_padding) - BSS_PAD_SIZE;
306 new_data_size=f_ohdr.dsize + file_sz_change;
308 if (!sections_reversed)
310 f_data.s_vaddr = f_bss.s_vaddr;
312 f_data.s_paddr += file_sz_change;
314 if (f_data.s_size + f_nextdata.s_size != f_ohdr.dsize)
316 printf("section size doesn't tally with dsize %lx != %lx\n",
317 f_data.s_size + f_nextdata.s_size, f_ohdr.dsize);
320 f_data.s_size += file_sz_change;
321 lseek (a_new, 0, SEEK_SET);
322 /* write file header */
323 f_hdr.f_symptr += file_sz_change;
328 printf("writing file header\n");
329 if (write(a_new, &f_hdr, sizeof(f_hdr)) != sizeof(f_hdr))
331 PERROR("failed to write file header");
333 /* write optional header fixing dsize & bsize*/
334 printf("writing optional header\n");
335 printf("new data size is %lx, >= %lx\n", new_data_size,
336 f_ohdr.dsize + f_ohdr.bsize);
337 if (new_data_size < f_ohdr.dsize + f_ohdr.bsize )
339 printf("warning: new data size is < approx\n");
341 f_ohdr.dsize=new_data_size;
342 f_ohdr.bsize=BSS_PAD_SIZE;
343 if (write(a_new, &f_ohdr, sizeof(f_ohdr)) != sizeof(f_ohdr))
345 PERROR("failed to write optional header");
347 /* write text as is */
348 printf("writing text header (unchanged)\n");
350 if (write(a_new, &f_text, sizeof(f_text)) != sizeof(f_text))
352 PERROR("failed to write text header");
355 /* Write small bss section. */
356 if (!sections_reversed)
358 f_bss.s_size = BSS_PAD_SIZE;
359 f_bss.s_paddr = BSS_PAD_SIZE;
360 f_bss.s_vaddr = f_data.s_vaddr - BSS_PAD_SIZE;
361 if (write(a_new, &f_bss, sizeof(f_bss)) != sizeof(f_bss))
363 PERROR("failed to write bss header");
367 /* write new data header */
368 printf("writing .data header\n");
370 if (write(a_new, &f_data, sizeof(f_data)) != sizeof(f_data))
372 PERROR("failed to write data header");
375 /* Write small bss section. */
376 if (sections_reversed)
378 f_bss.s_size = BSS_PAD_SIZE;
379 f_bss.s_paddr = BSS_PAD_SIZE;
380 f_bss.s_vaddr = f_nextdata.s_vaddr - BSS_PAD_SIZE;
381 if (write(a_new, &f_bss, sizeof(f_bss)) != sizeof(f_bss))
383 PERROR("failed to write bss header");
387 printf("writing following data header\n");
388 f_nextdata.s_scnptr += file_sz_change;
389 if (f_nextdata.s_lnnoptr != 0) f_nextdata.s_lnnoptr += file_sz_change;
390 if (f_nextdata.s_relptr != 0) f_nextdata.s_relptr += file_sz_change;
391 if (write(a_new, &f_nextdata, sizeof(f_nextdata)) != sizeof(f_nextdata))
393 PERROR("failed to write nextdata header");
396 /* copy other section headers adjusting the file offset */
397 for (i=0; i<(f_hdr.f_nscns-3); i++)
399 if (read (a_out, §ion, sizeof (section)) != sizeof (section))
401 PERROR ("no .data section");
404 section.s_scnptr += file_sz_change;
405 if (section.s_lnnoptr != 0) section.s_lnnoptr += file_sz_change;
406 if (section.s_relptr != 0) section.s_relptr += file_sz_change;
408 if (write(a_new, §ion, sizeof(section)) != sizeof(section))
410 PERROR("failed to write data header");
414 /* dump bss to maintain offsets */
415 memset(&f_bss, 0, sizeof(f_bss));
416 if (write(a_new, &f_bss, sizeof(f_bss)) != sizeof(f_bss))
418 PERROR("failed to write bss header");
421 size=lseek(a_new, 0, SEEK_CUR);
422 CHECK_AOUT_POS(size);
424 /* copy eveything else until start of data */
425 size = f_data_s_scnptr - lseek (a_out, 0, SEEK_CUR);
427 printf ("copying executable up to data section ... %lx bytes\n",
429 dup_file_area(a_out, a_new, size);
431 CHECK_AOUT_POS(f_data_s_scnptr);
433 if (!sections_reversed)
435 /* dump bss + padding between sections, sans small bss pad */
436 printf ("dumping .bss into executable... %lx bytes\n", bss_size);
437 if (write(a_new, bss_start, bss_size) != (int)bss_size)
439 PERROR("failed to write bss section");
442 /* pad, needs to be zero */
443 bss_padding = (new_bss_size - bss_size) - BSS_PAD_SIZE;
446 PERROR("padded .bss too small");
448 printf ("padding .bss ... %lx bytes\n", bss_padding);
449 empty_space = malloc(bss_padding);
450 memset(empty_space, 0, bss_padding);
451 if (write(a_new, empty_space, bss_padding) != (int)bss_padding)
453 PERROR("failed to write bss section");
458 /* tell dumped version not to free pure heap */
459 static_heap_dumped = 1;
460 /* Get a pointer to the raw data in our address space. */
461 printf ("dumping .data section... %lx bytes\n", data_size);
462 if (write(a_new, data_start_va, data_size) != (int)data_size)
464 PERROR("failed to write data section");
466 /* were going to use free again ... */
467 static_heap_dumped = 0;
469 size = lseek(a_out, f_data_s_scnptr + data_size, SEEK_SET);
471 if (!sections_reversed)
473 size = f_nextdata_s_scnptr - size;
474 dup_file_area(a_out, a_new, size);
478 /* need to pad to bss with data in file */
479 printf ("padding .data ... %lx bytes\n", data_padding);
480 size = (f_bss_s_vaddr - f_data_s_vaddr) - data_size;
481 dup_file_area(a_out, a_new, size);
483 /* dump bss + padding between sections */
484 printf ("dumping .bss into executable... %lx bytes\n", bss_size);
485 if (write(a_new, bss_start, bss_size) != (int)bss_size)
487 PERROR("failed to write bss section");
490 /* pad, needs to be zero */
491 bss_padding = (new_bss_size - bss_size) - BSS_PAD_SIZE;
494 PERROR("padded .bss too small");
496 printf ("padding .bss ... %lx bytes\n", bss_padding);
497 empty_space = malloc(bss_padding);
498 memset(empty_space, 0, bss_padding);
499 if (write(a_new, empty_space, bss_padding) != (int)bss_padding)
501 PERROR("failed to write bss section");
504 if (lseek(a_new, 0, SEEK_CUR) != f_nextdata.s_scnptr)
506 printf("at %lx should be at %lx\n",
507 lseek(a_new, 0, SEEK_CUR),
508 f_nextdata.s_scnptr);
509 PERROR("file positioning error\n");
511 lseek(a_out, f_nextdata_s_scnptr, SEEK_SET);
514 CHECK_AOUT_POS(f_nextdata_s_scnptr);
516 /* now dump - nextdata don't need to do this cygwin ds is in .data! */
517 printf ("dumping following data section... %lx bytes\n", f_nextdata.s_size);
519 dup_file_area(a_out,a_new,f_nextdata.s_size);
521 /* write rest of file */
522 printf ("writing rest of file\n");
523 size = lseek(a_out, 0, SEEK_END);
524 size = size - (f_nextdata_s_scnptr + f_nextdata.s_size); /* length remaining in a_out */
525 lseek(a_out, f_nextdata_s_scnptr + f_nextdata.s_size, SEEK_SET);
527 dup_file_area(a_out, a_new, size);
531 * copy from aout to anew
533 static void dup_file_area(int a_out, int a_new, long size)
537 for (; size > 0; size -= sizeof (page))
539 n = size > sizeof (page) ? sizeof (page) : size;
540 if (read (a_out, page, n) != n || write (a_new, page, n) != n)
542 PERROR ("dump_out()");
548 static void write_int_to_bss(int a_out, int a_new, void* va, void* newval)
552 cpos = lseek(a_new, 0, SEEK_CUR);
553 if (va < bss_start || va > bss_start + f_data.s_size)
555 PERROR("address not in data space\n");
557 lseek(a_new, f_data.s_scnptr + ((unsigned long)va -
558 (unsigned long)bss_start), SEEK_SET);
559 if (write(a_new, newval, sizeof(int)) != (int)sizeof(int))
561 PERROR("failed to write int value");
563 lseek(a_new, cpos, SEEK_SET);
567 #endif /* HAVE_A_OUT_H */