Commit | Line | Data |
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429ab54e | 1 | /* Copyright (C) 1985, 1986, 1987, 1988, 1992, 1993, 1994, 2001, 2002, 2003, |
76b6f707 | 2 | 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc. |
7dd63af1 RS |
3 | |
4 | This file is part of GNU Emacs. | |
5 | ||
9ec0b715 | 6 | GNU Emacs is free software: you can redistribute it and/or modify |
7dd63af1 | 7 | it under the terms of the GNU General Public License as published by |
9ec0b715 GM |
8 | the Free Software Foundation, either version 3 of the License, or |
9 | (at your option) any later version. | |
7dd63af1 RS |
10 | |
11 | GNU Emacs is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
9ec0b715 | 17 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ |
7dd63af1 RS |
18 | |
19 | ||
20 | /* | |
21 | * unexec.c - Convert a running program into an a.out file. | |
22 | * | |
23 | * Author: Spencer W. Thomas | |
24 | * Computer Science Dept. | |
25 | * University of Utah | |
26 | * Date: Tue Mar 2 1982 | |
27 | * Modified heavily since then. | |
28 | * | |
29 | * Synopsis: | |
30 | * unexec (new_name, a_name, data_start, bss_start, entry_address) | |
31 | * char *new_name, *a_name; | |
32 | * unsigned data_start, bss_start, entry_address; | |
33 | * | |
34 | * Takes a snapshot of the program and makes an a.out format file in the | |
35 | * file named by the string argument new_name. | |
36 | * If a_name is non-NULL, the symbol table will be taken from the given file. | |
37 | * On some machines, an existing a_name file is required. | |
38 | * | |
39 | * The boundaries within the a.out file may be adjusted with the data_start | |
40 | * and bss_start arguments. Either or both may be given as 0 for defaults. | |
41 | * | |
42 | * Data_start gives the boundary between the text segment and the data | |
43 | * segment of the program. The text segment can contain shared, read-only | |
44 | * program code and literal data, while the data segment is always unshared | |
45 | * and unprotected. Data_start gives the lowest unprotected address. | |
46 | * The value you specify may be rounded down to a suitable boundary | |
47 | * as required by the machine you are using. | |
48 | * | |
49 | * Specifying zero for data_start means the boundary between text and data | |
50 | * should not be the same as when the program was loaded. | |
51 | * If NO_REMAP is defined, the argument data_start is ignored and the | |
52 | * segment boundaries are never changed. | |
53 | * | |
54 | * Bss_start indicates how much of the data segment is to be saved in the | |
55 | * a.out file and restored when the program is executed. It gives the lowest | |
56 | * unsaved address, and is rounded up to a page boundary. The default when 0 | |
57 | * is given assumes that the entire data segment is to be stored, including | |
58 | * the previous data and bss as well as any additional storage allocated with | |
59 | * break (2). | |
60 | * | |
61 | * The new file is set up to start at entry_address. | |
62 | * | |
63 | * If you make improvements I'd like to get them too. | |
64 | * harpo!utah-cs!thomas, thomas@Utah-20 | |
65 | * | |
66 | */ | |
67 | ||
68 | /* Modified to support SysVr3 shared libraries by James Van Artsdalen | |
69 | * of Dell Computer Corporation. james@bigtex.cactus.org. | |
70 | */ | |
71 | ||
72 | /* There are several compilation parameters affecting unexec: | |
73 | ||
74 | * COFF | |
75 | ||
76 | Define this if your system uses COFF for executables. | |
265a9e55 | 77 | |
7dd63af1 RS |
78 | * NO_REMAP |
79 | ||
80 | Define this if you do not want to try to save Emacs's pure data areas | |
81 | as part of the text segment. | |
82 | ||
83 | Saving them as text is good because it allows users to share more. | |
84 | ||
85 | However, on machines that locate the text area far from the data area, | |
86 | the boundary cannot feasibly be moved. Such machines require | |
87 | NO_REMAP. | |
88 | ||
89 | Also, remapping can cause trouble with the built-in startup routine | |
90 | /lib/crt0.o, which defines `environ' as an initialized variable. | |
91 | Dumping `environ' as pure does not work! So, to use remapping, | |
92 | you must write a startup routine for your machine in Emacs's crt0.c. | |
93 | If NO_REMAP is defined, Emacs uses the system's crt0.o. | |
94 | ||
95 | * SECTION_ALIGNMENT | |
96 | ||
97 | Some machines that use COFF executables require that each section | |
98 | start on a certain boundary *in the COFF file*. Such machines should | |
99 | define SECTION_ALIGNMENT to a mask of the low-order bits that must be | |
100 | zero on such a boundary. This mask is used to control padding between | |
101 | segments in the COFF file. | |
102 | ||
103 | If SECTION_ALIGNMENT is not defined, the segments are written | |
104 | consecutively with no attempt at alignment. This is right for | |
105 | unmodified system V. | |
106 | ||
107 | * SEGMENT_MASK | |
108 | ||
109 | Some machines require that the beginnings and ends of segments | |
110 | *in core* be on certain boundaries. For most machines, a page | |
111 | boundary is sufficient. That is the default. When a larger | |
112 | boundary is needed, define SEGMENT_MASK to a mask of | |
113 | the bits that must be zero on such a boundary. | |
114 | ||
7dd63af1 RS |
115 | * ADJUST_EXEC_HEADER |
116 | ||
117 | This macro can be used to generate statements to adjust or | |
118 | initialize nonstandard fields in the file header | |
119 | ||
7dd63af1 RS |
120 | */ |
121 | ||
122 | #ifndef emacs | |
123 | #define PERROR(arg) perror (arg); return -1 | |
124 | #else | |
18160b98 | 125 | #include <config.h> |
7dd63af1 RS |
126 | #define PERROR(file) report_error (file, new) |
127 | #endif | |
128 | ||
129 | #ifndef CANNOT_DUMP /* all rest of file! */ | |
130 | ||
f914a6bf | 131 | #ifdef HAVE_COFF_H |
2a4487ac | 132 | #include <coff.h> |
3680bdc6 | 133 | #ifdef MSDOS |
8eb2807f RS |
134 | #if __DJGPP__ > 1 |
135 | #include <fcntl.h> /* for O_RDONLY, O_RDWR */ | |
c17a2102 KH |
136 | #include <crt0.h> /* for _crt0_startup_flags and its bits */ |
137 | static int save_djgpp_startup_flags; | |
8d228cb0 | 138 | #endif /* __DJGPP__ > 1 */ |
3680bdc6 RS |
139 | #define filehdr external_filehdr |
140 | #define scnhdr external_scnhdr | |
141 | #define syment external_syment | |
142 | #define auxent external_auxent | |
143 | #define n_numaux e_numaux | |
144 | #define n_type e_type | |
145 | struct aouthdr | |
146 | { | |
234d3183 RS |
147 | unsigned short magic; /* type of file */ |
148 | unsigned short vstamp; /* version stamp */ | |
149 | unsigned long tsize; /* text size in bytes, padded to FW bdry*/ | |
150 | unsigned long dsize; /* initialized data " " */ | |
151 | unsigned long bsize; /* uninitialized data " " */ | |
152 | unsigned long entry; /* entry pt. */ | |
153 | unsigned long text_start;/* base of text used for this file */ | |
154 | unsigned long data_start;/* base of data used for this file */ | |
3680bdc6 | 155 | }; |
3680bdc6 | 156 | #endif /* not MSDOS */ |
f914a6bf | 157 | #else /* not HAVE_COFF_H */ |
8d228cb0 | 158 | #include <a.out.h> |
f914a6bf | 159 | #endif /* not HAVE_COFF_H */ |
265a9e55 | 160 | |
f34e2e18 RS |
161 | /* Define getpagesize if the system does not. |
162 | Note that this may depend on symbols defined in a.out.h. */ | |
7dd63af1 RS |
163 | #include "getpagesize.h" |
164 | ||
165 | #ifndef makedev /* Try to detect types.h already loaded */ | |
166 | #include <sys/types.h> | |
265a9e55 | 167 | #endif /* makedev */ |
7dd63af1 RS |
168 | #include <stdio.h> |
169 | #include <sys/stat.h> | |
170 | #include <errno.h> | |
171 | ||
f914a6bf | 172 | #include <sys/file.h> |
2d30a233 RM |
173 | |
174 | #ifndef O_RDONLY | |
175 | #define O_RDONLY 0 | |
176 | #endif | |
177 | #ifndef O_RDWR | |
178 | #define O_RDWR 2 | |
179 | #endif | |
180 | ||
181 | ||
7dd63af1 RS |
182 | extern char *start_of_text (); /* Start of text */ |
183 | extern char *start_of_data (); /* Start of initialized data */ | |
184 | ||
7dd63af1 RS |
185 | static long block_copy_start; /* Old executable start point */ |
186 | static struct filehdr f_hdr; /* File header */ | |
187 | static struct aouthdr f_ohdr; /* Optional file header (a.out) */ | |
188 | long bias; /* Bias to add for growth */ | |
189 | long lnnoptr; /* Pointer to line-number info within file */ | |
190 | #define SYMS_START block_copy_start | |
191 | ||
192 | static long text_scnptr; | |
193 | static long data_scnptr; | |
194 | ||
c8b14b5f RS |
195 | static long coff_offset; |
196 | ||
7dd63af1 RS |
197 | static int pagemask; |
198 | ||
199 | /* Correct an int which is the bit pattern of a pointer to a byte | |
200 | into an int which is the number of a byte. | |
201 | This is a no-op on ordinary machines, but not on all. */ | |
202 | ||
7dd63af1 | 203 | #define ADDR_CORRECT(x) ((char *)(x) - (char*)0) |
7dd63af1 RS |
204 | |
205 | #ifdef emacs | |
206 | ||
2d30a233 RM |
207 | #include "lisp.h" |
208 | ||
7dd63af1 RS |
209 | static |
210 | report_error (file, fd) | |
211 | char *file; | |
212 | int fd; | |
213 | { | |
214 | if (fd) | |
215 | close (fd); | |
2d30a233 | 216 | report_file_error ("Cannot unexec", Fcons (build_string (file), Qnil)); |
7dd63af1 RS |
217 | } |
218 | #endif /* emacs */ | |
219 | ||
220 | #define ERROR0(msg) report_error_1 (new, msg, 0, 0); return -1 | |
221 | #define ERROR1(msg,x) report_error_1 (new, msg, x, 0); return -1 | |
222 | #define ERROR2(msg,x,y) report_error_1 (new, msg, x, y); return -1 | |
223 | ||
224 | static | |
225 | report_error_1 (fd, msg, a1, a2) | |
226 | int fd; | |
227 | char *msg; | |
228 | int a1, a2; | |
229 | { | |
230 | close (fd); | |
231 | #ifdef emacs | |
232 | error (msg, a1, a2); | |
233 | #else | |
234 | fprintf (stderr, msg, a1, a2); | |
235 | fprintf (stderr, "\n"); | |
236 | #endif | |
237 | } | |
238 | \f | |
239 | static int make_hdr (); | |
240 | static int copy_text_and_data (); | |
241 | static int copy_sym (); | |
242 | static void mark_x (); | |
243 | ||
7dd63af1 RS |
244 | /* **************************************************************** |
245 | * make_hdr | |
246 | * | |
247 | * Make the header in the new a.out from the header in core. | |
248 | * Modify the text and data sizes. | |
249 | */ | |
250 | static int | |
251 | make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) | |
252 | int new, a_out; | |
253 | unsigned data_start, bss_start, entry_address; | |
254 | char *a_name; | |
255 | char *new_name; | |
256 | { | |
257 | int tem; | |
7dd63af1 RS |
258 | auto struct scnhdr f_thdr; /* Text section header */ |
259 | auto struct scnhdr f_dhdr; /* Data section header */ | |
260 | auto struct scnhdr f_bhdr; /* Bss section header */ | |
261 | auto struct scnhdr scntemp; /* Temporary section header */ | |
262 | register int scns; | |
7dd63af1 | 263 | unsigned int bss_end; |
7dd63af1 RS |
264 | |
265 | pagemask = getpagesize () - 1; | |
266 | ||
267 | /* Adjust text/data boundary. */ | |
268 | #ifdef NO_REMAP | |
269 | data_start = (int) start_of_data (); | |
270 | #else /* not NO_REMAP */ | |
271 | if (!data_start) | |
272 | data_start = (int) start_of_data (); | |
273 | #endif /* not NO_REMAP */ | |
274 | data_start = ADDR_CORRECT (data_start); | |
275 | ||
276 | #ifdef SEGMENT_MASK | |
277 | data_start = data_start & ~SEGMENT_MASK; /* (Down) to segment boundary. */ | |
278 | #else | |
279 | data_start = data_start & ~pagemask; /* (Down) to page boundary. */ | |
280 | #endif | |
281 | ||
282 | bss_end = ADDR_CORRECT (sbrk (0)) + pagemask; | |
283 | bss_end &= ~ pagemask; | |
284 | ||
285 | /* Adjust data/bss boundary. */ | |
286 | if (bss_start != 0) | |
287 | { | |
288 | bss_start = (ADDR_CORRECT (bss_start) + pagemask); | |
289 | /* (Up) to page bdry. */ | |
290 | bss_start &= ~ pagemask; | |
291 | if (bss_start > bss_end) | |
292 | { | |
293 | ERROR1 ("unexec: Specified bss_start (%u) is past end of program", | |
294 | bss_start); | |
295 | } | |
296 | } | |
297 | else | |
298 | bss_start = bss_end; | |
299 | ||
300 | if (data_start > bss_start) /* Can't have negative data size. */ | |
301 | { | |
302 | ERROR2 ("unexec: data_start (%u) can't be greater than bss_start (%u)", | |
303 | data_start, bss_start); | |
304 | } | |
305 | ||
c8b14b5f RS |
306 | coff_offset = 0L; /* stays zero, except in DJGPP */ |
307 | ||
7dd63af1 RS |
308 | /* Salvage as much info from the existing file as possible */ |
309 | if (a_out >= 0) | |
310 | { | |
c8b14b5f RS |
311 | #ifdef MSDOS |
312 | #if __DJGPP__ > 1 | |
313 | /* Support the coff-go32-exe format with a prepended stub, since | |
314 | this is what GCC 2.8.0 and later generates by default in DJGPP. */ | |
315 | unsigned short mz_header[3]; | |
316 | ||
317 | if (read (a_out, &mz_header, sizeof (mz_header)) != sizeof (mz_header)) | |
318 | { | |
319 | PERROR (a_name); | |
320 | } | |
321 | if (mz_header[0] == 0x5a4d || mz_header[0] == 0x4d5a) /* "MZ" or "ZM" */ | |
322 | { | |
323 | coff_offset = (long)mz_header[2] * 512L; | |
324 | if (mz_header[1]) | |
325 | coff_offset += (long)mz_header[1] - 512L; | |
326 | lseek (a_out, coff_offset, 0); | |
327 | } | |
328 | else | |
329 | lseek (a_out, 0L, 0); | |
330 | #endif /* __DJGPP__ > 1 */ | |
331 | #endif /* MSDOS */ | |
7dd63af1 RS |
332 | if (read (a_out, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr)) |
333 | { | |
334 | PERROR (a_name); | |
335 | } | |
336 | block_copy_start += sizeof (f_hdr); | |
337 | if (f_hdr.f_opthdr > 0) | |
338 | { | |
339 | if (read (a_out, &f_ohdr, sizeof (f_ohdr)) != sizeof (f_ohdr)) | |
340 | { | |
341 | PERROR (a_name); | |
342 | } | |
343 | block_copy_start += sizeof (f_ohdr); | |
344 | } | |
345 | /* Loop through section headers, copying them in */ | |
c8b14b5f | 346 | lseek (a_out, coff_offset + sizeof (f_hdr) + f_hdr.f_opthdr, 0); |
7dd63af1 RS |
347 | for (scns = f_hdr.f_nscns; scns > 0; scns--) { |
348 | if (read (a_out, &scntemp, sizeof (scntemp)) != sizeof (scntemp)) | |
349 | { | |
350 | PERROR (a_name); | |
351 | } | |
352 | if (scntemp.s_scnptr > 0L) | |
353 | { | |
354 | if (block_copy_start < scntemp.s_scnptr + scntemp.s_size) | |
355 | block_copy_start = scntemp.s_scnptr + scntemp.s_size; | |
356 | } | |
357 | if (strcmp (scntemp.s_name, ".text") == 0) | |
358 | { | |
359 | f_thdr = scntemp; | |
360 | } | |
361 | else if (strcmp (scntemp.s_name, ".data") == 0) | |
362 | { | |
363 | f_dhdr = scntemp; | |
364 | } | |
365 | else if (strcmp (scntemp.s_name, ".bss") == 0) | |
366 | { | |
367 | f_bhdr = scntemp; | |
368 | } | |
369 | } | |
370 | } | |
371 | else | |
372 | { | |
373 | ERROR0 ("can't build a COFF file from scratch yet"); | |
374 | } | |
375 | ||
376 | /* Now we alter the contents of all the f_*hdr variables | |
377 | to correspond to what we want to dump. */ | |
378 | ||
7dd63af1 | 379 | f_hdr.f_flags |= (F_RELFLG | F_EXEC); |
7dd63af1 RS |
380 | #ifndef NO_REMAP |
381 | f_ohdr.text_start = (long) start_of_text (); | |
382 | f_ohdr.tsize = data_start - f_ohdr.text_start; | |
383 | f_ohdr.data_start = data_start; | |
384 | #endif /* NO_REMAP */ | |
385 | f_ohdr.dsize = bss_start - f_ohdr.data_start; | |
386 | f_ohdr.bsize = bss_end - bss_start; | |
7dd63af1 RS |
387 | /* On some machines, the old values are right. |
388 | ??? Maybe on all machines with NO_REMAP. */ | |
389 | f_thdr.s_size = f_ohdr.tsize; | |
390 | f_thdr.s_scnptr = sizeof (f_hdr) + sizeof (f_ohdr); | |
391 | f_thdr.s_scnptr += (f_hdr.f_nscns) * (sizeof (f_thdr)); | |
7dd63af1 RS |
392 | lnnoptr = f_thdr.s_lnnoptr; |
393 | #ifdef SECTION_ALIGNMENT | |
394 | /* Some systems require special alignment | |
395 | of the sections in the file itself. */ | |
396 | f_thdr.s_scnptr | |
397 | = (f_thdr.s_scnptr + SECTION_ALIGNMENT) & ~SECTION_ALIGNMENT; | |
398 | #endif /* SECTION_ALIGNMENT */ | |
7dd63af1 | 399 | text_scnptr = f_thdr.s_scnptr; |
7dd63af1 | 400 | f_dhdr.s_paddr = f_ohdr.data_start; |
7dd63af1 RS |
401 | f_dhdr.s_vaddr = f_ohdr.data_start; |
402 | f_dhdr.s_size = f_ohdr.dsize; | |
403 | f_dhdr.s_scnptr = f_thdr.s_scnptr + f_thdr.s_size; | |
404 | #ifdef SECTION_ALIGNMENT | |
405 | /* Some systems require special alignment | |
406 | of the sections in the file itself. */ | |
407 | f_dhdr.s_scnptr | |
408 | = (f_dhdr.s_scnptr + SECTION_ALIGNMENT) & ~SECTION_ALIGNMENT; | |
409 | #endif /* SECTION_ALIGNMENT */ | |
410 | #ifdef DATA_SECTION_ALIGNMENT | |
411 | /* Some systems require special alignment | |
412 | of the data section only. */ | |
413 | f_dhdr.s_scnptr | |
414 | = (f_dhdr.s_scnptr + DATA_SECTION_ALIGNMENT) & ~DATA_SECTION_ALIGNMENT; | |
415 | #endif /* DATA_SECTION_ALIGNMENT */ | |
416 | data_scnptr = f_dhdr.s_scnptr; | |
7dd63af1 | 417 | f_bhdr.s_paddr = f_ohdr.data_start + f_ohdr.dsize; |
7dd63af1 RS |
418 | f_bhdr.s_vaddr = f_ohdr.data_start + f_ohdr.dsize; |
419 | f_bhdr.s_size = f_ohdr.bsize; | |
420 | f_bhdr.s_scnptr = 0L; | |
7dd63af1 | 421 | bias = f_dhdr.s_scnptr + f_dhdr.s_size - block_copy_start; |
7dd63af1 RS |
422 | |
423 | if (f_hdr.f_symptr > 0L) | |
424 | { | |
425 | f_hdr.f_symptr += bias; | |
426 | } | |
427 | ||
428 | if (f_thdr.s_lnnoptr > 0L) | |
429 | { | |
430 | f_thdr.s_lnnoptr += bias; | |
431 | } | |
432 | ||
433 | #ifdef ADJUST_EXEC_HEADER | |
434 | ADJUST_EXEC_HEADER; | |
435 | #endif /* ADJUST_EXEC_HEADER */ | |
436 | ||
437 | if (write (new, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr)) | |
438 | { | |
439 | PERROR (new_name); | |
440 | } | |
441 | ||
442 | if (write (new, &f_ohdr, sizeof (f_ohdr)) != sizeof (f_ohdr)) | |
443 | { | |
444 | PERROR (new_name); | |
445 | } | |
446 | ||
7dd63af1 RS |
447 | if (write (new, &f_thdr, sizeof (f_thdr)) != sizeof (f_thdr)) |
448 | { | |
449 | PERROR (new_name); | |
450 | } | |
451 | ||
452 | if (write (new, &f_dhdr, sizeof (f_dhdr)) != sizeof (f_dhdr)) | |
453 | { | |
454 | PERROR (new_name); | |
455 | } | |
456 | ||
457 | if (write (new, &f_bhdr, sizeof (f_bhdr)) != sizeof (f_bhdr)) | |
458 | { | |
459 | PERROR (new_name); | |
460 | } | |
461 | ||
7dd63af1 RS |
462 | return (0); |
463 | ||
7dd63af1 RS |
464 | } |
465 | \f | |
730f4d72 EZ |
466 | write_segment (new, ptr, end) |
467 | int new; | |
468 | register char *ptr, *end; | |
469 | { | |
470 | register int i, nwrite, ret; | |
471 | char buf[80]; | |
472 | #ifndef USE_CRT_DLL | |
473 | extern int errno; | |
474 | #endif | |
475 | /* This is the normal amount to write at once. | |
476 | It is the size of block that NFS uses. */ | |
477 | int writesize = 1 << 13; | |
478 | int pagesize = getpagesize (); | |
479 | char zeros[1 << 13]; | |
480 | ||
481 | bzero (zeros, sizeof (zeros)); | |
482 | ||
483 | for (i = 0; ptr < end;) | |
484 | { | |
485 | /* Distance to next multiple of writesize. */ | |
486 | nwrite = (((int) ptr + writesize) & -writesize) - (int) ptr; | |
487 | /* But not beyond specified end. */ | |
488 | if (nwrite > end - ptr) nwrite = end - ptr; | |
489 | ret = write (new, ptr, nwrite); | |
490 | /* If write gets a page fault, it means we reached | |
491 | a gap between the old text segment and the old data segment. | |
492 | This gap has probably been remapped into part of the text segment. | |
493 | So write zeros for it. */ | |
494 | if (ret == -1 | |
495 | #ifdef EFAULT | |
496 | && errno == EFAULT | |
497 | #endif | |
498 | ) | |
499 | { | |
500 | /* Write only a page of zeros at once, | |
2b34df4e | 501 | so that we don't overshoot the start |
730f4d72 EZ |
502 | of the valid memory in the old data segment. */ |
503 | if (nwrite > pagesize) | |
504 | nwrite = pagesize; | |
505 | write (new, zeros, nwrite); | |
506 | } | |
507 | #if 0 /* Now that we have can ask `write' to write more than a page, | |
508 | it is legit for write do less than the whole amount specified. */ | |
509 | else if (nwrite != ret) | |
510 | { | |
511 | sprintf (buf, | |
512 | "unexec write failure: addr 0x%x, fileno %d, size 0x%x, wrote 0x%x, errno %d", | |
513 | ptr, new, nwrite, ret, errno); | |
514 | PERROR (buf); | |
515 | } | |
516 | #endif | |
517 | i += nwrite; | |
518 | ptr += nwrite; | |
519 | } | |
520 | } | |
7dd63af1 RS |
521 | /* **************************************************************** |
522 | * copy_text_and_data | |
523 | * | |
524 | * Copy the text and data segments from memory to the new a.out | |
525 | */ | |
526 | static int | |
527 | copy_text_and_data (new, a_out) | |
528 | int new, a_out; | |
529 | { | |
530 | register char *end; | |
531 | register char *ptr; | |
532 | ||
8eb2807f RS |
533 | #ifdef MSDOS |
534 | #if __DJGPP__ >= 2 | |
535 | /* Dump the original table of exception handlers, not the one | |
536 | where our exception hooks are registered. */ | |
537 | __djgpp_exception_toggle (); | |
c17a2102 KH |
538 | |
539 | /* Switch off startup flags that might have been set at runtime | |
540 | and which might change the way that dumped Emacs works. */ | |
541 | save_djgpp_startup_flags = _crt0_startup_flags; | |
542 | _crt0_startup_flags &= ~(_CRT0_FLAG_NO_LFN | _CRT0_FLAG_NEARPTR); | |
8eb2807f RS |
543 | #endif |
544 | #endif | |
545 | ||
7dd63af1 RS |
546 | lseek (new, (long) text_scnptr, 0); |
547 | ptr = (char *) f_ohdr.text_start; | |
7dd63af1 RS |
548 | end = ptr + f_ohdr.tsize; |
549 | write_segment (new, ptr, end); | |
550 | ||
551 | lseek (new, (long) data_scnptr, 0); | |
552 | ptr = (char *) f_ohdr.data_start; | |
553 | end = ptr + f_ohdr.dsize; | |
554 | write_segment (new, ptr, end); | |
555 | ||
8eb2807f RS |
556 | #ifdef MSDOS |
557 | #if __DJGPP__ >= 2 | |
558 | /* Restore our exception hooks. */ | |
559 | __djgpp_exception_toggle (); | |
c17a2102 KH |
560 | |
561 | /* Restore the startup flags. */ | |
562 | _crt0_startup_flags = save_djgpp_startup_flags; | |
8eb2807f RS |
563 | #endif |
564 | #endif | |
565 | ||
7dd63af1 RS |
566 | |
567 | return 0; | |
568 | } | |
7dd63af1 RS |
569 | \f |
570 | /* **************************************************************** | |
571 | * copy_sym | |
572 | * | |
573 | * Copy the relocation information and symbol table from the a.out to the new | |
574 | */ | |
575 | static int | |
576 | copy_sym (new, a_out, a_name, new_name) | |
577 | int new, a_out; | |
578 | char *a_name, *new_name; | |
579 | { | |
580 | char page[1024]; | |
581 | int n; | |
582 | ||
583 | if (a_out < 0) | |
584 | return 0; | |
585 | ||
7dd63af1 RS |
586 | if (SYMS_START == 0L) |
587 | return 0; | |
7dd63af1 | 588 | |
7dd63af1 | 589 | if (lnnoptr) /* if there is line number info */ |
c8b14b5f | 590 | lseek (a_out, coff_offset + lnnoptr, 0); /* start copying from there */ |
7dd63af1 | 591 | else |
c8b14b5f | 592 | lseek (a_out, coff_offset + SYMS_START, 0); /* Position a.out to symtab. */ |
7dd63af1 RS |
593 | |
594 | while ((n = read (a_out, page, sizeof page)) > 0) | |
595 | { | |
596 | if (write (new, page, n) != n) | |
597 | { | |
598 | PERROR (new_name); | |
599 | } | |
600 | } | |
601 | if (n < 0) | |
602 | { | |
603 | PERROR (a_name); | |
604 | } | |
605 | return 0; | |
606 | } | |
607 | \f | |
608 | /* **************************************************************** | |
609 | * mark_x | |
610 | * | |
eb8c3be9 | 611 | * After successfully building the new a.out, mark it executable |
7dd63af1 RS |
612 | */ |
613 | static void | |
614 | mark_x (name) | |
615 | char *name; | |
616 | { | |
617 | struct stat sbuf; | |
618 | int um; | |
619 | int new = 0; /* for PERROR */ | |
620 | ||
621 | um = umask (777); | |
622 | umask (um); | |
623 | if (stat (name, &sbuf) == -1) | |
624 | { | |
625 | PERROR (name); | |
626 | } | |
627 | sbuf.st_mode |= 0111 & ~um; | |
628 | if (chmod (name, sbuf.st_mode) == -1) | |
629 | PERROR (name); | |
630 | } | |
631 | \f | |
7dd63af1 RS |
632 | #ifndef COFF_BSD_SYMBOLS |
633 | ||
634 | /* | |
635 | * If the COFF file contains a symbol table and a line number section, | |
636 | * then any auxiliary entries that have values for x_lnnoptr must | |
637 | * be adjusted by the amount that the line number section has moved | |
638 | * in the file (bias computed in make_hdr). The #@$%&* designers of | |
639 | * the auxiliary entry structures used the absolute file offsets for | |
640 | * the line number entry rather than an offset from the start of the | |
641 | * line number section! | |
642 | * | |
643 | * When I figure out how to scan through the symbol table and pick out | |
644 | * the auxiliary entries that need adjustment, this routine will | |
645 | * be fixed. As it is now, all such entries are wrong and sdb | |
646 | * will complain. Fred Fish, UniSoft Systems Inc. | |
647 | */ | |
648 | ||
649 | /* This function is probably very slow. Instead of reopening the new | |
650 | file for input and output it should copy from the old to the new | |
651 | using the two descriptors already open (WRITEDESC and READDESC). | |
652 | Instead of reading one small structure at a time it should use | |
653 | a reasonable size buffer. But I don't have time to work on such | |
654 | things, so I am installing it as submitted to me. -- RMS. */ | |
655 | ||
656 | adjust_lnnoptrs (writedesc, readdesc, new_name) | |
657 | int writedesc; | |
658 | int readdesc; | |
659 | char *new_name; | |
660 | { | |
661 | register int nsyms; | |
662 | register int new; | |
7dd63af1 RS |
663 | struct syment symentry; |
664 | union auxent auxentry; | |
7dd63af1 RS |
665 | |
666 | if (!lnnoptr || !f_hdr.f_symptr) | |
667 | return 0; | |
668 | ||
3680bdc6 RS |
669 | #ifdef MSDOS |
670 | if ((new = writedesc) < 0) | |
671 | #else | |
2d30a233 | 672 | if ((new = open (new_name, O_RDWR)) < 0) |
3680bdc6 | 673 | #endif |
7dd63af1 RS |
674 | { |
675 | PERROR (new_name); | |
676 | return -1; | |
677 | } | |
678 | ||
679 | lseek (new, f_hdr.f_symptr, 0); | |
680 | for (nsyms = 0; nsyms < f_hdr.f_nsyms; nsyms++) | |
681 | { | |
682 | read (new, &symentry, SYMESZ); | |
683 | if (symentry.n_numaux) | |
684 | { | |
685 | read (new, &auxentry, AUXESZ); | |
686 | nsyms++; | |
1ba3de00 RS |
687 | if (ISFCN (symentry.n_type) || symentry.n_type == 0x2400) |
688 | { | |
689 | auxentry.x_sym.x_fcnary.x_fcn.x_lnnoptr += bias; | |
690 | lseek (new, -AUXESZ, 1); | |
691 | write (new, &auxentry, AUXESZ); | |
692 | } | |
7dd63af1 RS |
693 | } |
694 | } | |
3680bdc6 | 695 | #ifndef MSDOS |
7dd63af1 | 696 | close (new); |
3680bdc6 RS |
697 | #endif |
698 | return 0; | |
7dd63af1 RS |
699 | } |
700 | ||
701 | #endif /* COFF_BSD_SYMBOLS */ | |
702 | ||
730f4d72 EZ |
703 | /* **************************************************************** |
704 | * unexec | |
705 | * | |
706 | * driving logic. | |
707 | */ | |
708 | unexec (new_name, a_name, data_start, bss_start, entry_address) | |
709 | char *new_name, *a_name; | |
710 | unsigned data_start, bss_start, entry_address; | |
711 | { | |
712 | int new, a_out = -1; | |
713 | ||
714 | if (a_name && (a_out = open (a_name, O_RDONLY)) < 0) | |
715 | { | |
716 | PERROR (a_name); | |
717 | } | |
718 | if ((new = creat (new_name, 0666)) < 0) | |
719 | { | |
720 | PERROR (new_name); | |
721 | } | |
722 | ||
723 | if (make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) < 0 | |
724 | || copy_text_and_data (new, a_out) < 0 | |
725 | || copy_sym (new, a_out, a_name, new_name) < 0 | |
730f4d72 EZ |
726 | #ifndef COFF_BSD_SYMBOLS |
727 | || adjust_lnnoptrs (new, a_out, new_name) < 0 | |
730f4d72 EZ |
728 | #endif |
729 | ) | |
730 | { | |
731 | close (new); | |
732 | /* unlink (new_name); /* Failed, unlink new a.out */ | |
733 | return -1; | |
734 | } | |
735 | ||
736 | close (new); | |
737 | if (a_out >= 0) | |
738 | close (a_out); | |
739 | mark_x (new_name); | |
740 | return 0; | |
741 | } | |
742 | ||
7dd63af1 | 743 | #endif /* not CANNOT_DUMP */ |
ab5796a9 MB |
744 | |
745 | /* arch-tag: 62409b69-e27a-4a7c-9413-0210d6b54e7f | |
746 | (do not change this comment) */ |