Commit | Line | Data |
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429ab54e | 1 | /* Copyright (C) 1985, 1986, 1987, 1988, 1992, 1993, 1994, 2001, 2002, 2003, |
114f9c96 | 2 | 2004, 2005, 2006, 2007, 2008, 2009, 2010 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 | 134 | #include <fcntl.h> /* for O_RDONLY, O_RDWR */ |
c17a2102 KH |
135 | #include <crt0.h> /* for _crt0_startup_flags and its bits */ |
136 | static int save_djgpp_startup_flags; | |
3680bdc6 RS |
137 | #define filehdr external_filehdr |
138 | #define scnhdr external_scnhdr | |
139 | #define syment external_syment | |
140 | #define auxent external_auxent | |
141 | #define n_numaux e_numaux | |
142 | #define n_type e_type | |
143 | struct aouthdr | |
144 | { | |
234d3183 RS |
145 | unsigned short magic; /* type of file */ |
146 | unsigned short vstamp; /* version stamp */ | |
147 | unsigned long tsize; /* text size in bytes, padded to FW bdry*/ | |
148 | unsigned long dsize; /* initialized data " " */ | |
149 | unsigned long bsize; /* uninitialized data " " */ | |
150 | unsigned long entry; /* entry pt. */ | |
151 | unsigned long text_start;/* base of text used for this file */ | |
152 | unsigned long data_start;/* base of data used for this file */ | |
3680bdc6 | 153 | }; |
3680bdc6 | 154 | #endif /* not MSDOS */ |
f914a6bf | 155 | #else /* not HAVE_COFF_H */ |
8d228cb0 | 156 | #include <a.out.h> |
f914a6bf | 157 | #endif /* not HAVE_COFF_H */ |
265a9e55 | 158 | |
f34e2e18 RS |
159 | /* Define getpagesize if the system does not. |
160 | Note that this may depend on symbols defined in a.out.h. */ | |
7dd63af1 RS |
161 | #include "getpagesize.h" |
162 | ||
163 | #ifndef makedev /* Try to detect types.h already loaded */ | |
164 | #include <sys/types.h> | |
265a9e55 | 165 | #endif /* makedev */ |
7dd63af1 RS |
166 | #include <stdio.h> |
167 | #include <sys/stat.h> | |
168 | #include <errno.h> | |
169 | ||
f914a6bf | 170 | #include <sys/file.h> |
2d30a233 RM |
171 | |
172 | #ifndef O_RDONLY | |
173 | #define O_RDONLY 0 | |
174 | #endif | |
175 | #ifndef O_RDWR | |
176 | #define O_RDWR 2 | |
177 | #endif | |
178 | ||
179 | ||
7dd63af1 RS |
180 | extern char *start_of_text (); /* Start of text */ |
181 | extern char *start_of_data (); /* Start of initialized data */ | |
182 | ||
7dd63af1 RS |
183 | static long block_copy_start; /* Old executable start point */ |
184 | static struct filehdr f_hdr; /* File header */ | |
185 | static struct aouthdr f_ohdr; /* Optional file header (a.out) */ | |
186 | long bias; /* Bias to add for growth */ | |
187 | long lnnoptr; /* Pointer to line-number info within file */ | |
188 | #define SYMS_START block_copy_start | |
189 | ||
190 | static long text_scnptr; | |
191 | static long data_scnptr; | |
192 | ||
c8b14b5f RS |
193 | static long coff_offset; |
194 | ||
7dd63af1 RS |
195 | static int pagemask; |
196 | ||
197 | /* Correct an int which is the bit pattern of a pointer to a byte | |
198 | into an int which is the number of a byte. | |
199 | This is a no-op on ordinary machines, but not on all. */ | |
200 | ||
7dd63af1 | 201 | #define ADDR_CORRECT(x) ((char *)(x) - (char*)0) |
7dd63af1 RS |
202 | |
203 | #ifdef emacs | |
204 | ||
d7306fe6 | 205 | #include <setjmp.h> |
2d30a233 RM |
206 | #include "lisp.h" |
207 | ||
7dd63af1 RS |
208 | static |
209 | report_error (file, fd) | |
210 | char *file; | |
211 | int fd; | |
212 | { | |
213 | if (fd) | |
214 | close (fd); | |
2d30a233 | 215 | report_file_error ("Cannot unexec", Fcons (build_string (file), Qnil)); |
7dd63af1 RS |
216 | } |
217 | #endif /* emacs */ | |
218 | ||
219 | #define ERROR0(msg) report_error_1 (new, msg, 0, 0); return -1 | |
220 | #define ERROR1(msg,x) report_error_1 (new, msg, x, 0); return -1 | |
221 | #define ERROR2(msg,x,y) report_error_1 (new, msg, x, y); return -1 | |
222 | ||
223 | static | |
224 | report_error_1 (fd, msg, a1, a2) | |
225 | int fd; | |
226 | char *msg; | |
227 | int a1, a2; | |
228 | { | |
229 | close (fd); | |
230 | #ifdef emacs | |
231 | error (msg, a1, a2); | |
232 | #else | |
233 | fprintf (stderr, msg, a1, a2); | |
234 | fprintf (stderr, "\n"); | |
235 | #endif | |
236 | } | |
237 | \f | |
238 | static int make_hdr (); | |
239 | static int copy_text_and_data (); | |
240 | static int copy_sym (); | |
241 | static void mark_x (); | |
242 | ||
7dd63af1 RS |
243 | /* **************************************************************** |
244 | * make_hdr | |
245 | * | |
246 | * Make the header in the new a.out from the header in core. | |
247 | * Modify the text and data sizes. | |
248 | */ | |
249 | static int | |
250 | make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) | |
251 | int new, a_out; | |
252 | unsigned data_start, bss_start, entry_address; | |
253 | char *a_name; | |
254 | char *new_name; | |
255 | { | |
256 | int tem; | |
7dd63af1 RS |
257 | auto struct scnhdr f_thdr; /* Text section header */ |
258 | auto struct scnhdr f_dhdr; /* Data section header */ | |
259 | auto struct scnhdr f_bhdr; /* Bss section header */ | |
260 | auto struct scnhdr scntemp; /* Temporary section header */ | |
261 | register int scns; | |
7dd63af1 | 262 | unsigned int bss_end; |
7dd63af1 RS |
263 | |
264 | pagemask = getpagesize () - 1; | |
265 | ||
266 | /* Adjust text/data boundary. */ | |
267 | #ifdef NO_REMAP | |
268 | data_start = (int) start_of_data (); | |
269 | #else /* not NO_REMAP */ | |
270 | if (!data_start) | |
271 | data_start = (int) start_of_data (); | |
272 | #endif /* not NO_REMAP */ | |
273 | data_start = ADDR_CORRECT (data_start); | |
274 | ||
275 | #ifdef SEGMENT_MASK | |
276 | data_start = data_start & ~SEGMENT_MASK; /* (Down) to segment boundary. */ | |
277 | #else | |
278 | data_start = data_start & ~pagemask; /* (Down) to page boundary. */ | |
279 | #endif | |
280 | ||
281 | bss_end = ADDR_CORRECT (sbrk (0)) + pagemask; | |
282 | bss_end &= ~ pagemask; | |
283 | ||
284 | /* Adjust data/bss boundary. */ | |
285 | if (bss_start != 0) | |
286 | { | |
287 | bss_start = (ADDR_CORRECT (bss_start) + pagemask); | |
288 | /* (Up) to page bdry. */ | |
289 | bss_start &= ~ pagemask; | |
290 | if (bss_start > bss_end) | |
291 | { | |
292 | ERROR1 ("unexec: Specified bss_start (%u) is past end of program", | |
293 | bss_start); | |
294 | } | |
295 | } | |
296 | else | |
297 | bss_start = bss_end; | |
298 | ||
299 | if (data_start > bss_start) /* Can't have negative data size. */ | |
300 | { | |
301 | ERROR2 ("unexec: data_start (%u) can't be greater than bss_start (%u)", | |
302 | data_start, bss_start); | |
303 | } | |
304 | ||
c8b14b5f RS |
305 | coff_offset = 0L; /* stays zero, except in DJGPP */ |
306 | ||
7dd63af1 RS |
307 | /* Salvage as much info from the existing file as possible */ |
308 | if (a_out >= 0) | |
309 | { | |
c8b14b5f | 310 | #ifdef MSDOS |
c8b14b5f RS |
311 | /* Support the coff-go32-exe format with a prepended stub, since |
312 | this is what GCC 2.8.0 and later generates by default in DJGPP. */ | |
313 | unsigned short mz_header[3]; | |
314 | ||
315 | if (read (a_out, &mz_header, sizeof (mz_header)) != sizeof (mz_header)) | |
316 | { | |
317 | PERROR (a_name); | |
318 | } | |
319 | if (mz_header[0] == 0x5a4d || mz_header[0] == 0x4d5a) /* "MZ" or "ZM" */ | |
320 | { | |
321 | coff_offset = (long)mz_header[2] * 512L; | |
322 | if (mz_header[1]) | |
323 | coff_offset += (long)mz_header[1] - 512L; | |
324 | lseek (a_out, coff_offset, 0); | |
325 | } | |
326 | else | |
327 | lseek (a_out, 0L, 0); | |
c8b14b5f | 328 | #endif /* MSDOS */ |
7dd63af1 RS |
329 | if (read (a_out, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr)) |
330 | { | |
331 | PERROR (a_name); | |
332 | } | |
333 | block_copy_start += sizeof (f_hdr); | |
334 | if (f_hdr.f_opthdr > 0) | |
335 | { | |
336 | if (read (a_out, &f_ohdr, sizeof (f_ohdr)) != sizeof (f_ohdr)) | |
337 | { | |
338 | PERROR (a_name); | |
339 | } | |
340 | block_copy_start += sizeof (f_ohdr); | |
341 | } | |
342 | /* Loop through section headers, copying them in */ | |
c8b14b5f | 343 | lseek (a_out, coff_offset + sizeof (f_hdr) + f_hdr.f_opthdr, 0); |
7dd63af1 RS |
344 | for (scns = f_hdr.f_nscns; scns > 0; scns--) { |
345 | if (read (a_out, &scntemp, sizeof (scntemp)) != sizeof (scntemp)) | |
346 | { | |
347 | PERROR (a_name); | |
348 | } | |
349 | if (scntemp.s_scnptr > 0L) | |
350 | { | |
351 | if (block_copy_start < scntemp.s_scnptr + scntemp.s_size) | |
352 | block_copy_start = scntemp.s_scnptr + scntemp.s_size; | |
353 | } | |
354 | if (strcmp (scntemp.s_name, ".text") == 0) | |
355 | { | |
356 | f_thdr = scntemp; | |
357 | } | |
358 | else if (strcmp (scntemp.s_name, ".data") == 0) | |
359 | { | |
360 | f_dhdr = scntemp; | |
361 | } | |
362 | else if (strcmp (scntemp.s_name, ".bss") == 0) | |
363 | { | |
364 | f_bhdr = scntemp; | |
365 | } | |
366 | } | |
367 | } | |
368 | else | |
369 | { | |
370 | ERROR0 ("can't build a COFF file from scratch yet"); | |
371 | } | |
372 | ||
373 | /* Now we alter the contents of all the f_*hdr variables | |
374 | to correspond to what we want to dump. */ | |
375 | ||
7dd63af1 | 376 | f_hdr.f_flags |= (F_RELFLG | F_EXEC); |
7dd63af1 RS |
377 | #ifndef NO_REMAP |
378 | f_ohdr.text_start = (long) start_of_text (); | |
379 | f_ohdr.tsize = data_start - f_ohdr.text_start; | |
380 | f_ohdr.data_start = data_start; | |
381 | #endif /* NO_REMAP */ | |
382 | f_ohdr.dsize = bss_start - f_ohdr.data_start; | |
383 | f_ohdr.bsize = bss_end - bss_start; | |
7dd63af1 RS |
384 | /* On some machines, the old values are right. |
385 | ??? Maybe on all machines with NO_REMAP. */ | |
386 | f_thdr.s_size = f_ohdr.tsize; | |
387 | f_thdr.s_scnptr = sizeof (f_hdr) + sizeof (f_ohdr); | |
388 | f_thdr.s_scnptr += (f_hdr.f_nscns) * (sizeof (f_thdr)); | |
7dd63af1 RS |
389 | lnnoptr = f_thdr.s_lnnoptr; |
390 | #ifdef SECTION_ALIGNMENT | |
391 | /* Some systems require special alignment | |
392 | of the sections in the file itself. */ | |
393 | f_thdr.s_scnptr | |
394 | = (f_thdr.s_scnptr + SECTION_ALIGNMENT) & ~SECTION_ALIGNMENT; | |
395 | #endif /* SECTION_ALIGNMENT */ | |
7dd63af1 | 396 | text_scnptr = f_thdr.s_scnptr; |
7dd63af1 | 397 | f_dhdr.s_paddr = f_ohdr.data_start; |
7dd63af1 RS |
398 | f_dhdr.s_vaddr = f_ohdr.data_start; |
399 | f_dhdr.s_size = f_ohdr.dsize; | |
400 | f_dhdr.s_scnptr = f_thdr.s_scnptr + f_thdr.s_size; | |
401 | #ifdef SECTION_ALIGNMENT | |
402 | /* Some systems require special alignment | |
403 | of the sections in the file itself. */ | |
404 | f_dhdr.s_scnptr | |
405 | = (f_dhdr.s_scnptr + SECTION_ALIGNMENT) & ~SECTION_ALIGNMENT; | |
406 | #endif /* SECTION_ALIGNMENT */ | |
407 | #ifdef DATA_SECTION_ALIGNMENT | |
408 | /* Some systems require special alignment | |
409 | of the data section only. */ | |
410 | f_dhdr.s_scnptr | |
411 | = (f_dhdr.s_scnptr + DATA_SECTION_ALIGNMENT) & ~DATA_SECTION_ALIGNMENT; | |
412 | #endif /* DATA_SECTION_ALIGNMENT */ | |
413 | data_scnptr = f_dhdr.s_scnptr; | |
7dd63af1 | 414 | f_bhdr.s_paddr = f_ohdr.data_start + f_ohdr.dsize; |
7dd63af1 RS |
415 | f_bhdr.s_vaddr = f_ohdr.data_start + f_ohdr.dsize; |
416 | f_bhdr.s_size = f_ohdr.bsize; | |
417 | f_bhdr.s_scnptr = 0L; | |
7dd63af1 | 418 | bias = f_dhdr.s_scnptr + f_dhdr.s_size - block_copy_start; |
7dd63af1 RS |
419 | |
420 | if (f_hdr.f_symptr > 0L) | |
421 | { | |
422 | f_hdr.f_symptr += bias; | |
423 | } | |
424 | ||
425 | if (f_thdr.s_lnnoptr > 0L) | |
426 | { | |
427 | f_thdr.s_lnnoptr += bias; | |
428 | } | |
429 | ||
430 | #ifdef ADJUST_EXEC_HEADER | |
431 | ADJUST_EXEC_HEADER; | |
432 | #endif /* ADJUST_EXEC_HEADER */ | |
433 | ||
434 | if (write (new, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr)) | |
435 | { | |
436 | PERROR (new_name); | |
437 | } | |
438 | ||
439 | if (write (new, &f_ohdr, sizeof (f_ohdr)) != sizeof (f_ohdr)) | |
440 | { | |
441 | PERROR (new_name); | |
442 | } | |
443 | ||
7dd63af1 RS |
444 | if (write (new, &f_thdr, sizeof (f_thdr)) != sizeof (f_thdr)) |
445 | { | |
446 | PERROR (new_name); | |
447 | } | |
448 | ||
449 | if (write (new, &f_dhdr, sizeof (f_dhdr)) != sizeof (f_dhdr)) | |
450 | { | |
451 | PERROR (new_name); | |
452 | } | |
453 | ||
454 | if (write (new, &f_bhdr, sizeof (f_bhdr)) != sizeof (f_bhdr)) | |
455 | { | |
456 | PERROR (new_name); | |
457 | } | |
458 | ||
7dd63af1 RS |
459 | return (0); |
460 | ||
7dd63af1 RS |
461 | } |
462 | \f | |
730f4d72 EZ |
463 | write_segment (new, ptr, end) |
464 | int new; | |
465 | register char *ptr, *end; | |
466 | { | |
467 | register int i, nwrite, ret; | |
468 | char buf[80]; | |
730f4d72 EZ |
469 | /* This is the normal amount to write at once. |
470 | It is the size of block that NFS uses. */ | |
471 | int writesize = 1 << 13; | |
472 | int pagesize = getpagesize (); | |
473 | char zeros[1 << 13]; | |
474 | ||
72af86bd | 475 | memset (zeros, 0, sizeof (zeros)); |
730f4d72 EZ |
476 | |
477 | for (i = 0; ptr < end;) | |
478 | { | |
479 | /* Distance to next multiple of writesize. */ | |
480 | nwrite = (((int) ptr + writesize) & -writesize) - (int) ptr; | |
481 | /* But not beyond specified end. */ | |
482 | if (nwrite > end - ptr) nwrite = end - ptr; | |
483 | ret = write (new, ptr, nwrite); | |
484 | /* If write gets a page fault, it means we reached | |
485 | a gap between the old text segment and the old data segment. | |
486 | This gap has probably been remapped into part of the text segment. | |
487 | So write zeros for it. */ | |
488 | if (ret == -1 | |
489 | #ifdef EFAULT | |
490 | && errno == EFAULT | |
491 | #endif | |
492 | ) | |
493 | { | |
494 | /* Write only a page of zeros at once, | |
2b34df4e | 495 | so that we don't overshoot the start |
730f4d72 EZ |
496 | of the valid memory in the old data segment. */ |
497 | if (nwrite > pagesize) | |
498 | nwrite = pagesize; | |
499 | write (new, zeros, nwrite); | |
500 | } | |
501 | #if 0 /* Now that we have can ask `write' to write more than a page, | |
502 | it is legit for write do less than the whole amount specified. */ | |
503 | else if (nwrite != ret) | |
504 | { | |
505 | sprintf (buf, | |
506 | "unexec write failure: addr 0x%x, fileno %d, size 0x%x, wrote 0x%x, errno %d", | |
507 | ptr, new, nwrite, ret, errno); | |
508 | PERROR (buf); | |
509 | } | |
510 | #endif | |
511 | i += nwrite; | |
512 | ptr += nwrite; | |
513 | } | |
514 | } | |
7dd63af1 RS |
515 | /* **************************************************************** |
516 | * copy_text_and_data | |
517 | * | |
518 | * Copy the text and data segments from memory to the new a.out | |
519 | */ | |
520 | static int | |
521 | copy_text_and_data (new, a_out) | |
522 | int new, a_out; | |
523 | { | |
524 | register char *end; | |
525 | register char *ptr; | |
526 | ||
8eb2807f | 527 | #ifdef MSDOS |
8eb2807f RS |
528 | /* Dump the original table of exception handlers, not the one |
529 | where our exception hooks are registered. */ | |
530 | __djgpp_exception_toggle (); | |
c17a2102 KH |
531 | |
532 | /* Switch off startup flags that might have been set at runtime | |
533 | and which might change the way that dumped Emacs works. */ | |
534 | save_djgpp_startup_flags = _crt0_startup_flags; | |
535 | _crt0_startup_flags &= ~(_CRT0_FLAG_NO_LFN | _CRT0_FLAG_NEARPTR); | |
8eb2807f RS |
536 | #endif |
537 | ||
7dd63af1 RS |
538 | lseek (new, (long) text_scnptr, 0); |
539 | ptr = (char *) f_ohdr.text_start; | |
7dd63af1 RS |
540 | end = ptr + f_ohdr.tsize; |
541 | write_segment (new, ptr, end); | |
542 | ||
543 | lseek (new, (long) data_scnptr, 0); | |
544 | ptr = (char *) f_ohdr.data_start; | |
545 | end = ptr + f_ohdr.dsize; | |
546 | write_segment (new, ptr, end); | |
547 | ||
8eb2807f | 548 | #ifdef MSDOS |
8eb2807f RS |
549 | /* Restore our exception hooks. */ |
550 | __djgpp_exception_toggle (); | |
c17a2102 KH |
551 | |
552 | /* Restore the startup flags. */ | |
553 | _crt0_startup_flags = save_djgpp_startup_flags; | |
8eb2807f | 554 | #endif |
8eb2807f | 555 | |
7dd63af1 RS |
556 | |
557 | return 0; | |
558 | } | |
7dd63af1 RS |
559 | \f |
560 | /* **************************************************************** | |
561 | * copy_sym | |
562 | * | |
563 | * Copy the relocation information and symbol table from the a.out to the new | |
564 | */ | |
565 | static int | |
566 | copy_sym (new, a_out, a_name, new_name) | |
567 | int new, a_out; | |
568 | char *a_name, *new_name; | |
569 | { | |
570 | char page[1024]; | |
571 | int n; | |
572 | ||
573 | if (a_out < 0) | |
574 | return 0; | |
575 | ||
7dd63af1 RS |
576 | if (SYMS_START == 0L) |
577 | return 0; | |
7dd63af1 | 578 | |
7dd63af1 | 579 | if (lnnoptr) /* if there is line number info */ |
c8b14b5f | 580 | lseek (a_out, coff_offset + lnnoptr, 0); /* start copying from there */ |
7dd63af1 | 581 | else |
c8b14b5f | 582 | lseek (a_out, coff_offset + SYMS_START, 0); /* Position a.out to symtab. */ |
7dd63af1 RS |
583 | |
584 | while ((n = read (a_out, page, sizeof page)) > 0) | |
585 | { | |
586 | if (write (new, page, n) != n) | |
587 | { | |
588 | PERROR (new_name); | |
589 | } | |
590 | } | |
591 | if (n < 0) | |
592 | { | |
593 | PERROR (a_name); | |
594 | } | |
595 | return 0; | |
596 | } | |
597 | \f | |
598 | /* **************************************************************** | |
599 | * mark_x | |
600 | * | |
eb8c3be9 | 601 | * After successfully building the new a.out, mark it executable |
7dd63af1 RS |
602 | */ |
603 | static void | |
604 | mark_x (name) | |
605 | char *name; | |
606 | { | |
607 | struct stat sbuf; | |
608 | int um; | |
609 | int new = 0; /* for PERROR */ | |
610 | ||
611 | um = umask (777); | |
612 | umask (um); | |
613 | if (stat (name, &sbuf) == -1) | |
614 | { | |
615 | PERROR (name); | |
616 | } | |
617 | sbuf.st_mode |= 0111 & ~um; | |
618 | if (chmod (name, sbuf.st_mode) == -1) | |
619 | PERROR (name); | |
620 | } | |
621 | \f | |
7dd63af1 RS |
622 | |
623 | /* | |
624 | * If the COFF file contains a symbol table and a line number section, | |
625 | * then any auxiliary entries that have values for x_lnnoptr must | |
626 | * be adjusted by the amount that the line number section has moved | |
627 | * in the file (bias computed in make_hdr). The #@$%&* designers of | |
628 | * the auxiliary entry structures used the absolute file offsets for | |
629 | * the line number entry rather than an offset from the start of the | |
630 | * line number section! | |
631 | * | |
632 | * When I figure out how to scan through the symbol table and pick out | |
633 | * the auxiliary entries that need adjustment, this routine will | |
634 | * be fixed. As it is now, all such entries are wrong and sdb | |
635 | * will complain. Fred Fish, UniSoft Systems Inc. | |
636 | */ | |
637 | ||
638 | /* This function is probably very slow. Instead of reopening the new | |
639 | file for input and output it should copy from the old to the new | |
640 | using the two descriptors already open (WRITEDESC and READDESC). | |
641 | Instead of reading one small structure at a time it should use | |
642 | a reasonable size buffer. But I don't have time to work on such | |
643 | things, so I am installing it as submitted to me. -- RMS. */ | |
644 | ||
645 | adjust_lnnoptrs (writedesc, readdesc, new_name) | |
646 | int writedesc; | |
647 | int readdesc; | |
648 | char *new_name; | |
649 | { | |
650 | register int nsyms; | |
651 | register int new; | |
7dd63af1 RS |
652 | struct syment symentry; |
653 | union auxent auxentry; | |
7dd63af1 RS |
654 | |
655 | if (!lnnoptr || !f_hdr.f_symptr) | |
656 | return 0; | |
657 | ||
3680bdc6 RS |
658 | #ifdef MSDOS |
659 | if ((new = writedesc) < 0) | |
660 | #else | |
2d30a233 | 661 | if ((new = open (new_name, O_RDWR)) < 0) |
3680bdc6 | 662 | #endif |
7dd63af1 RS |
663 | { |
664 | PERROR (new_name); | |
665 | return -1; | |
666 | } | |
667 | ||
668 | lseek (new, f_hdr.f_symptr, 0); | |
669 | for (nsyms = 0; nsyms < f_hdr.f_nsyms; nsyms++) | |
670 | { | |
671 | read (new, &symentry, SYMESZ); | |
672 | if (symentry.n_numaux) | |
673 | { | |
674 | read (new, &auxentry, AUXESZ); | |
675 | nsyms++; | |
1ba3de00 RS |
676 | if (ISFCN (symentry.n_type) || symentry.n_type == 0x2400) |
677 | { | |
678 | auxentry.x_sym.x_fcnary.x_fcn.x_lnnoptr += bias; | |
679 | lseek (new, -AUXESZ, 1); | |
680 | write (new, &auxentry, AUXESZ); | |
681 | } | |
7dd63af1 RS |
682 | } |
683 | } | |
3680bdc6 | 684 | #ifndef MSDOS |
7dd63af1 | 685 | close (new); |
3680bdc6 RS |
686 | #endif |
687 | return 0; | |
7dd63af1 RS |
688 | } |
689 | ||
730f4d72 EZ |
690 | /* **************************************************************** |
691 | * unexec | |
692 | * | |
693 | * driving logic. | |
694 | */ | |
695 | unexec (new_name, a_name, data_start, bss_start, entry_address) | |
696 | char *new_name, *a_name; | |
697 | unsigned data_start, bss_start, entry_address; | |
698 | { | |
699 | int new, a_out = -1; | |
700 | ||
701 | if (a_name && (a_out = open (a_name, O_RDONLY)) < 0) | |
702 | { | |
703 | PERROR (a_name); | |
704 | } | |
705 | if ((new = creat (new_name, 0666)) < 0) | |
706 | { | |
707 | PERROR (new_name); | |
708 | } | |
709 | ||
710 | if (make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) < 0 | |
711 | || copy_text_and_data (new, a_out) < 0 | |
712 | || copy_sym (new, a_out, a_name, new_name) < 0 | |
730f4d72 | 713 | || adjust_lnnoptrs (new, a_out, new_name) < 0 |
730f4d72 EZ |
714 | ) |
715 | { | |
716 | close (new); | |
717 | /* unlink (new_name); /* Failed, unlink new a.out */ | |
718 | return -1; | |
719 | } | |
720 | ||
721 | close (new); | |
722 | if (a_out >= 0) | |
723 | close (a_out); | |
724 | mark_x (new_name); | |
725 | return 0; | |
726 | } | |
727 | ||
7dd63af1 | 728 | #endif /* not CANNOT_DUMP */ |
ab5796a9 MB |
729 | |
730 | /* arch-tag: 62409b69-e27a-4a7c-9413-0210d6b54e7f | |
731 | (do not change this comment) */ |