Use a 32-bit floating-point limb size; support 8-bit float
[nasm.git] / output / outelf32.c
blob62f6c37e4e062448443396defa5647177dea8018
1 /* outelf.c output routines for the Netwide Assembler to produce
2 * ELF32 (i386 of course) object file format
4 * The Netwide Assembler is copyright (C) 1996 Simon Tatham and
5 * Julian Hall. All rights reserved. The software is
6 * redistributable under the licence given in the file "Licence"
7 * distributed in the NASM archive.
8 */
10 #include "compiler.h"
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include <string.h>
15 #include <ctype.h>
16 #include <inttypes.h>
18 #include "nasm.h"
19 #include "nasmlib.h"
20 #include "stdscan.h"
21 #include "outform.h"
23 #ifdef OF_ELF32
26 * Relocation types.
28 enum reloc_type {
29 R_386_32 = 1, /* ordinary absolute relocation */
30 R_386_PC32 = 2, /* PC-relative relocation */
31 R_386_GOT32 = 3, /* an offset into GOT */
32 R_386_PLT32 = 4, /* a PC-relative offset into PLT */
33 R_386_COPY = 5, /* ??? */
34 R_386_GLOB_DAT = 6, /* ??? */
35 R_386_JUMP_SLOT = 7, /* ??? */
36 R_386_RELATIVE = 8, /* ??? */
37 R_386_GOTOFF = 9, /* an offset from GOT base */
38 R_386_GOTPC = 10, /* a PC-relative offset _to_ GOT */
39 /* These are GNU extensions, but useful */
40 R_386_16 = 20, /* A 16-bit absolute relocation */
41 R_386_PC16 = 21, /* A 16-bit PC-relative relocation */
42 R_386_8 = 22, /* An 8-bit absolute relocation */
43 R_386_PC8 = 23 /* An 8-bit PC-relative relocation */
46 struct Reloc {
47 struct Reloc *next;
48 int32_t address; /* relative to _start_ of section */
49 int32_t symbol; /* symbol index */
50 int type; /* type of relocation */
53 struct Symbol {
54 int32_t strpos; /* string table position of name */
55 int32_t section; /* section ID of the symbol */
56 int type; /* symbol type */
57 int other; /* symbol visibility */
58 int32_t value; /* address, or COMMON variable align */
59 int32_t size; /* size of symbol */
60 int32_t globnum; /* symbol table offset if global */
61 struct Symbol *next; /* list of globals in each section */
62 struct Symbol *nextfwd; /* list of unresolved-size symbols */
63 char *name; /* used temporarily if in above list */
66 #define SHT_PROGBITS 1
67 #define SHT_NOBITS 8
69 #define SHF_WRITE 1
70 #define SHF_ALLOC 2
71 #define SHF_EXECINSTR 4
73 struct Section {
74 struct SAA *data;
75 uint32_t len, size, nrelocs;
76 int32_t index;
77 int type; /* SHT_PROGBITS or SHT_NOBITS */
78 int align; /* alignment: power of two */
79 uint32_t flags; /* section flags */
80 char *name;
81 struct SAA *rel;
82 int32_t rellen;
83 struct Reloc *head, **tail;
84 struct Symbol *gsyms; /* global symbols in section */
87 #define SECT_DELTA 32
88 static struct Section **sects;
89 static int nsects, sectlen;
91 #define SHSTR_DELTA 256
92 static char *shstrtab;
93 static int shstrtablen, shstrtabsize;
95 static struct SAA *syms;
96 static uint32_t nlocals, nglobs;
98 static int32_t def_seg;
100 static struct RAA *bsym;
102 static struct SAA *strs;
103 static uint32_t strslen;
105 static FILE *elffp;
106 static efunc error;
107 static evalfunc evaluate;
109 static struct Symbol *fwds;
111 static char elf_module[FILENAME_MAX];
113 extern struct ofmt of_elf32;
114 extern struct ofmt of_elf;
116 #define SHN_ABS 0xFFF1
117 #define SHN_COMMON 0xFFF2
118 #define SHN_UNDEF 0
120 #define SYM_GLOBAL 0x10
122 #define STT_NOTYPE 0 /* Symbol type is unspecified */
123 #define STT_OBJECT 1 /* Symbol is a data object */
124 #define STT_FUNC 2 /* Symbol is a code object */
125 #define STT_SECTION 3 /* Symbol associated with a section */
126 #define STT_FILE 4 /* Symbol's name is file name */
127 #define STT_COMMON 5 /* Symbol is a common data object */
128 #define STT_TLS 6 /* Symbol is thread-local data object*/
129 #define STT_NUM 7 /* Number of defined types. */
131 #define STV_DEFAULT 0
132 #define STV_INTERNAL 1
133 #define STV_HIDDEN 2
134 #define STV_PROTECTED 3
136 #define GLOBAL_TEMP_BASE 16 /* bigger than any constant sym id */
138 #define SEG_ALIGN 16 /* alignment of sections in file */
139 #define SEG_ALIGN_1 (SEG_ALIGN-1)
141 static const char align_str[SEG_ALIGN] = ""; /* ANSI will pad this with 0s */
143 #define ELF_MAX_SECTIONS 16 /* really 10, but let's play safe */
144 static struct ELF_SECTDATA {
145 void *data;
146 int32_t len;
147 bool is_saa;
148 } *elf_sects;
149 static int elf_nsect;
150 static int32_t elf_foffs;
152 static void elf_write(void);
153 static void elf_sect_write(struct Section *, const uint8_t *,
154 uint32_t);
155 static void elf_section_header(int, int, int, void *, bool, int32_t, int, int,
156 int, int);
157 static void elf_write_sections(void);
158 static struct SAA *elf_build_symtab(int32_t *, int32_t *);
159 static struct SAA *elf_build_reltab(int32_t *, struct Reloc *);
160 static void add_sectname(char *, char *);
162 /* this stuff is needed for the stabs debugging format */
163 #define N_SO 0x64 /* ID for main source file */
164 #define N_SOL 0x84 /* ID for sub-source file */
165 #define N_BINCL 0x82
166 #define N_EINCL 0xA2
167 #define N_SLINE 0x44
168 #define TY_STABSSYMLIN 0x40 /* ouch */
170 struct stabentry {
171 uint32_t n_strx;
172 uint8_t n_type;
173 uint8_t n_other;
174 uint16_t n_desc;
175 uint32_t n_value;
178 struct erel {
179 int offset, info;
182 struct symlininfo {
183 int offset;
184 int section; /* section index */
185 char *name; /* shallow-copied pointer of section name */
188 struct linelist {
189 struct symlininfo info;
190 int line;
191 char *filename;
192 struct linelist *next;
193 struct linelist *last;
196 static struct linelist *stabslines = 0;
197 static int stabs_immcall = 0;
198 static int currentline = 0;
199 static int numlinestabs = 0;
200 static char *stabs_filename = 0;
201 static int symtabsection;
202 static uint8_t *stabbuf = 0, *stabstrbuf = 0, *stabrelbuf = 0;
203 static int stablen, stabstrlen, stabrellen;
205 static struct dfmt df_stabs;
206 static struct Symbol *lastsym;
208 void stabs32_init(struct ofmt *, void *, FILE *, efunc);
209 void stabs32_linenum(const char *filename, int32_t linenumber, int32_t);
210 void stabs32_deflabel(char *, int32_t, int32_t, int, char *);
211 void stabs32_directive(const char *, const char *);
212 void stabs32_typevalue(int32_t);
213 void stabs32_output(int, void *);
214 void stabs32_generate(void);
215 void stabs32_cleanup(void);
217 /* end of stabs debugging stuff */
220 * Special section numbers which are used to define ELF special
221 * symbols, which can be used with WRT to provide PIC relocation
222 * types.
224 static int32_t elf_gotpc_sect, elf_gotoff_sect;
225 static int32_t elf_got_sect, elf_plt_sect;
226 static int32_t elf_sym_sect;
228 static void elf_init(FILE * fp, efunc errfunc, ldfunc ldef, evalfunc eval)
230 elffp = fp;
231 error = errfunc;
232 evaluate = eval;
233 (void)ldef; /* placate optimisers */
234 sects = NULL;
235 nsects = sectlen = 0;
236 syms = saa_init((int32_t)sizeof(struct Symbol));
237 nlocals = nglobs = 0;
238 bsym = raa_init();
239 strs = saa_init(1L);
240 saa_wbytes(strs, "\0", 1L);
241 saa_wbytes(strs, elf_module, (int32_t)(strlen(elf_module) + 1));
242 strslen = 2 + strlen(elf_module);
243 shstrtab = NULL;
244 shstrtablen = shstrtabsize = 0;;
245 add_sectname("", "");
247 fwds = NULL;
249 elf_gotpc_sect = seg_alloc();
250 ldef("..gotpc", elf_gotpc_sect + 1, 0L, NULL, false, false, &of_elf32,
251 error);
252 elf_gotoff_sect = seg_alloc();
253 ldef("..gotoff", elf_gotoff_sect + 1, 0L, NULL, false, false, &of_elf32,
254 error);
255 elf_got_sect = seg_alloc();
256 ldef("..got", elf_got_sect + 1, 0L, NULL, false, false, &of_elf32,
257 error);
258 elf_plt_sect = seg_alloc();
259 ldef("..plt", elf_plt_sect + 1, 0L, NULL, false, false, &of_elf32,
260 error);
261 elf_sym_sect = seg_alloc();
262 ldef("..sym", elf_sym_sect + 1, 0L, NULL, false, false, &of_elf32,
263 error);
265 def_seg = seg_alloc();
268 static void elf_cleanup(int debuginfo)
270 struct Reloc *r;
271 int i;
273 (void)debuginfo;
275 elf_write();
276 fclose(elffp);
277 for (i = 0; i < nsects; i++) {
278 if (sects[i]->type != SHT_NOBITS)
279 saa_free(sects[i]->data);
280 if (sects[i]->head)
281 saa_free(sects[i]->rel);
282 while (sects[i]->head) {
283 r = sects[i]->head;
284 sects[i]->head = sects[i]->head->next;
285 nasm_free(r);
288 nasm_free(sects);
289 saa_free(syms);
290 raa_free(bsym);
291 saa_free(strs);
292 if (of_elf32.current_dfmt) {
293 of_elf32.current_dfmt->cleanup();
297 static void add_sectname(char *firsthalf, char *secondhalf)
299 int len = strlen(firsthalf) + strlen(secondhalf);
300 while (shstrtablen + len + 1 > shstrtabsize)
301 shstrtab = nasm_realloc(shstrtab, (shstrtabsize += SHSTR_DELTA));
302 strcpy(shstrtab + shstrtablen, firsthalf);
303 strcat(shstrtab + shstrtablen, secondhalf);
304 shstrtablen += len + 1;
307 static int elf_make_section(char *name, int type, int flags, int align)
309 struct Section *s;
311 s = nasm_malloc(sizeof(*s));
313 if (type != SHT_NOBITS)
314 s->data = saa_init(1L);
315 s->head = NULL;
316 s->tail = &s->head;
317 s->len = s->size = 0;
318 s->nrelocs = 0;
319 if (!strcmp(name, ".text"))
320 s->index = def_seg;
321 else
322 s->index = seg_alloc();
323 add_sectname("", name);
324 s->name = nasm_malloc(1 + strlen(name));
325 strcpy(s->name, name);
326 s->type = type;
327 s->flags = flags;
328 s->align = align;
329 s->gsyms = NULL;
331 if (nsects >= sectlen)
332 sects =
333 nasm_realloc(sects, (sectlen += SECT_DELTA) * sizeof(*sects));
334 sects[nsects++] = s;
336 return nsects - 1;
339 static int32_t elf_section_names(char *name, int pass, int *bits)
341 char *p;
342 unsigned flags_and, flags_or;
343 int type, align, i;
346 * Default is 32 bits.
348 if (!name) {
349 *bits = 32;
350 return def_seg;
353 p = name;
354 while (*p && !isspace(*p))
355 p++;
356 if (*p)
357 *p++ = '\0';
358 flags_and = flags_or = type = align = 0;
360 while (*p && isspace(*p))
361 p++;
362 while (*p) {
363 char *q = p;
364 while (*p && !isspace(*p))
365 p++;
366 if (*p)
367 *p++ = '\0';
368 while (*p && isspace(*p))
369 p++;
371 if (!nasm_strnicmp(q, "align=", 6)) {
372 align = atoi(q + 6);
373 if (align == 0)
374 align = 1;
375 if ((align - 1) & align) { /* means it's not a power of two */
376 error(ERR_NONFATAL, "section alignment %d is not"
377 " a power of two", align);
378 align = 1;
380 } else if (!nasm_stricmp(q, "alloc")) {
381 flags_and |= SHF_ALLOC;
382 flags_or |= SHF_ALLOC;
383 } else if (!nasm_stricmp(q, "noalloc")) {
384 flags_and |= SHF_ALLOC;
385 flags_or &= ~SHF_ALLOC;
386 } else if (!nasm_stricmp(q, "exec")) {
387 flags_and |= SHF_EXECINSTR;
388 flags_or |= SHF_EXECINSTR;
389 } else if (!nasm_stricmp(q, "noexec")) {
390 flags_and |= SHF_EXECINSTR;
391 flags_or &= ~SHF_EXECINSTR;
392 } else if (!nasm_stricmp(q, "write")) {
393 flags_and |= SHF_WRITE;
394 flags_or |= SHF_WRITE;
395 } else if (!nasm_stricmp(q, "nowrite")) {
396 flags_and |= SHF_WRITE;
397 flags_or &= ~SHF_WRITE;
398 } else if (!nasm_stricmp(q, "progbits")) {
399 type = SHT_PROGBITS;
400 } else if (!nasm_stricmp(q, "nobits")) {
401 type = SHT_NOBITS;
405 if (!strcmp(name, ".comment") ||
406 !strcmp(name, ".shstrtab") ||
407 !strcmp(name, ".symtab") || !strcmp(name, ".strtab")) {
408 error(ERR_NONFATAL, "attempt to redefine reserved section"
409 "name `%s'", name);
410 return NO_SEG;
413 for (i = 0; i < nsects; i++)
414 if (!strcmp(name, sects[i]->name))
415 break;
416 if (i == nsects) {
417 if (!strcmp(name, ".text"))
418 i = elf_make_section(name, SHT_PROGBITS,
419 SHF_ALLOC | SHF_EXECINSTR, 16);
420 else if (!strcmp(name, ".rodata"))
421 i = elf_make_section(name, SHT_PROGBITS, SHF_ALLOC, 4);
422 else if (!strcmp(name, ".data"))
423 i = elf_make_section(name, SHT_PROGBITS,
424 SHF_ALLOC | SHF_WRITE, 4);
425 else if (!strcmp(name, ".bss"))
426 i = elf_make_section(name, SHT_NOBITS,
427 SHF_ALLOC | SHF_WRITE, 4);
428 else
429 i = elf_make_section(name, SHT_PROGBITS, SHF_ALLOC, 1);
430 if (type)
431 sects[i]->type = type;
432 if (align)
433 sects[i]->align = align;
434 sects[i]->flags &= ~flags_and;
435 sects[i]->flags |= flags_or;
436 } else if (pass == 1) {
437 if ((type && sects[i]->type != type)
438 || (align && sects[i]->align != align)
439 || (flags_and && ((sects[i]->flags & flags_and) != flags_or)))
440 error(ERR_WARNING, "section attributes ignored on"
441 " redeclaration of section `%s'", name);
444 return sects[i]->index;
447 static void elf_deflabel(char *name, int32_t segment, int32_t offset,
448 int is_global, char *special)
450 int pos = strslen;
451 struct Symbol *sym;
452 bool special_used = false;
454 #if defined(DEBUG) && DEBUG>2
455 fprintf(stderr,
456 " elf_deflabel: %s, seg=%ld, off=%ld, is_global=%d, %s\n",
457 name, segment, offset, is_global, special);
458 #endif
459 if (name[0] == '.' && name[1] == '.' && name[2] != '@') {
461 * This is a NASM special symbol. We never allow it into
462 * the ELF symbol table, even if it's a valid one. If it
463 * _isn't_ a valid one, we should barf immediately.
465 if (strcmp(name, "..gotpc") && strcmp(name, "..gotoff") &&
466 strcmp(name, "..got") && strcmp(name, "..plt") &&
467 strcmp(name, "..sym"))
468 error(ERR_NONFATAL, "unrecognised special symbol `%s'", name);
469 return;
472 if (is_global == 3) {
473 struct Symbol **s;
475 * Fix up a forward-reference symbol size from the first
476 * pass.
478 for (s = &fwds; *s; s = &(*s)->nextfwd)
479 if (!strcmp((*s)->name, name)) {
480 struct tokenval tokval;
481 expr *e;
482 char *p = special;
484 while (*p && !isspace(*p))
485 p++;
486 while (*p && isspace(*p))
487 p++;
488 stdscan_reset();
489 stdscan_bufptr = p;
490 tokval.t_type = TOKEN_INVALID;
491 e = evaluate(stdscan, NULL, &tokval, NULL, 1, error, NULL);
492 if (e) {
493 if (!is_simple(e))
494 error(ERR_NONFATAL, "cannot use relocatable"
495 " expression as symbol size");
496 else
497 (*s)->size = reloc_value(e);
501 * Remove it from the list of unresolved sizes.
503 nasm_free((*s)->name);
504 *s = (*s)->nextfwd;
505 return;
507 return; /* it wasn't an important one */
510 saa_wbytes(strs, name, (int32_t)(1 + strlen(name)));
511 strslen += 1 + strlen(name);
513 lastsym = sym = saa_wstruct(syms);
515 sym->strpos = pos;
516 sym->type = is_global ? SYM_GLOBAL : 0;
517 sym->other = STV_DEFAULT;
518 sym->size = 0;
519 if (segment == NO_SEG)
520 sym->section = SHN_ABS;
521 else {
522 int i;
523 sym->section = SHN_UNDEF;
524 if (nsects == 0 && segment == def_seg) {
525 int tempint;
526 if (segment != elf_section_names(".text", 2, &tempint))
527 error(ERR_PANIC,
528 "strange segment conditions in ELF driver");
529 sym->section = nsects;
530 } else {
531 for (i = 0; i < nsects; i++)
532 if (segment == sects[i]->index) {
533 sym->section = i + 1;
534 break;
539 if (is_global == 2) {
540 sym->size = offset;
541 sym->value = 0;
542 sym->section = SHN_COMMON;
544 * We have a common variable. Check the special text to see
545 * if it's a valid number and power of two; if so, store it
546 * as the alignment for the common variable.
548 if (special) {
549 bool err;
550 sym->value = readnum(special, &err);
551 if (err)
552 error(ERR_NONFATAL, "alignment constraint `%s' is not a"
553 " valid number", special);
554 else if ((sym->value | (sym->value - 1)) != 2 * sym->value - 1)
555 error(ERR_NONFATAL, "alignment constraint `%s' is not a"
556 " power of two", special);
558 special_used = true;
559 } else
560 sym->value = (sym->section == SHN_UNDEF ? 0 : offset);
562 if (sym->type == SYM_GLOBAL) {
564 * If sym->section == SHN_ABS, then the first line of the
565 * else section would cause a core dump, because its a reference
566 * beyond the end of the section array.
567 * This behaviour is exhibited by this code:
568 * GLOBAL crash_nasm
569 * crash_nasm equ 0
570 * To avoid such a crash, such requests are silently discarded.
571 * This may not be the best solution.
573 if (sym->section == SHN_UNDEF || sym->section == SHN_COMMON) {
574 bsym = raa_write(bsym, segment, nglobs);
575 } else if (sym->section != SHN_ABS) {
577 * This is a global symbol; so we must add it to the linked
578 * list of global symbols in its section. We'll push it on
579 * the beginning of the list, because it doesn't matter
580 * much which end we put it on and it's easier like this.
582 * In addition, we check the special text for symbol
583 * type and size information.
585 sym->next = sects[sym->section - 1]->gsyms;
586 sects[sym->section - 1]->gsyms = sym;
588 if (special) {
589 int n = strcspn(special, " \t");
591 if (!nasm_strnicmp(special, "function", n))
592 sym->type |= STT_FUNC;
593 else if (!nasm_strnicmp(special, "data", n) ||
594 !nasm_strnicmp(special, "object", n))
595 sym->type |= STT_OBJECT;
596 else if (!nasm_strnicmp(special, "notype", n))
597 sym->type |= STT_NOTYPE;
598 else
599 error(ERR_NONFATAL, "unrecognised symbol type `%.*s'",
600 n, special);
601 special += n;
603 while (isspace(*special))
604 ++special;
605 if (*special) {
606 n = strcspn(special, " \t");
607 if (!nasm_strnicmp(special, "default", n))
608 sym->other = STV_DEFAULT;
609 else if (!nasm_strnicmp(special, "internal", n))
610 sym->other = STV_INTERNAL;
611 else if (!nasm_strnicmp(special, "hidden", n))
612 sym->other = STV_HIDDEN;
613 else if (!nasm_strnicmp(special, "protected", n))
614 sym->other = STV_PROTECTED;
615 else
616 n = 0;
617 special += n;
620 if (*special) {
621 struct tokenval tokval;
622 expr *e;
623 int fwd = 0;
624 char *saveme = stdscan_bufptr; /* bugfix? fbk 8/10/00 */
626 while (special[n] && isspace(special[n]))
627 n++;
629 * We have a size expression; attempt to
630 * evaluate it.
632 stdscan_reset();
633 stdscan_bufptr = special + n;
634 tokval.t_type = TOKEN_INVALID;
635 e = evaluate(stdscan, NULL, &tokval, &fwd, 0, error,
636 NULL);
637 if (fwd) {
638 sym->nextfwd = fwds;
639 fwds = sym;
640 sym->name = nasm_strdup(name);
641 } else if (e) {
642 if (!is_simple(e))
643 error(ERR_NONFATAL, "cannot use relocatable"
644 " expression as symbol size");
645 else
646 sym->size = reloc_value(e);
648 stdscan_bufptr = saveme; /* bugfix? fbk 8/10/00 */
650 special_used = true;
653 sym->globnum = nglobs;
654 nglobs++;
655 } else
656 nlocals++;
658 if (special && !special_used)
659 error(ERR_NONFATAL, "no special symbol features supported here");
662 static void elf_add_reloc(struct Section *sect, int32_t segment, int type)
664 struct Reloc *r;
666 r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
667 sect->tail = &r->next;
668 r->next = NULL;
670 r->address = sect->len;
671 if (segment == NO_SEG)
672 r->symbol = 0;
673 else {
674 int i;
675 r->symbol = 0;
676 for (i = 0; i < nsects; i++)
677 if (segment == sects[i]->index)
678 r->symbol = i + 2;
679 if (!r->symbol)
680 r->symbol = GLOBAL_TEMP_BASE + raa_read(bsym, segment);
682 r->type = type;
684 sect->nrelocs++;
688 * This routine deals with ..got and ..sym relocations: the more
689 * complicated kinds. In shared-library writing, some relocations
690 * with respect to global symbols must refer to the precise symbol
691 * rather than referring to an offset from the base of the section
692 * _containing_ the symbol. Such relocations call to this routine,
693 * which searches the symbol list for the symbol in question.
695 * R_386_GOT32 references require the _exact_ symbol address to be
696 * used; R_386_32 references can be at an offset from the symbol.
697 * The boolean argument `exact' tells us this.
699 * Return value is the adjusted value of `addr', having become an
700 * offset from the symbol rather than the section. Should always be
701 * zero when returning from an exact call.
703 * Limitation: if you define two symbols at the same place,
704 * confusion will occur.
706 * Inefficiency: we search, currently, using a linked list which
707 * isn't even necessarily sorted.
709 static int32_t elf_add_gsym_reloc(struct Section *sect,
710 int32_t segment, int32_t offset,
711 int type, bool exact)
713 struct Reloc *r;
714 struct Section *s;
715 struct Symbol *sym, *sm;
716 int i;
719 * First look up the segment/offset pair and find a global
720 * symbol corresponding to it. If it's not one of our segments,
721 * then it must be an external symbol, in which case we're fine
722 * doing a normal elf_add_reloc after first sanity-checking
723 * that the offset from the symbol is zero.
725 s = NULL;
726 for (i = 0; i < nsects; i++)
727 if (segment == sects[i]->index) {
728 s = sects[i];
729 break;
731 if (!s) {
732 if (exact && offset != 0)
733 error(ERR_NONFATAL, "unable to find a suitable global symbol"
734 " for this reference");
735 else
736 elf_add_reloc(sect, segment, type);
737 return offset;
740 if (exact) {
742 * Find a symbol pointing _exactly_ at this one.
744 for (sym = s->gsyms; sym; sym = sym->next)
745 if (sym->value == offset)
746 break;
747 } else {
749 * Find the nearest symbol below this one.
751 sym = NULL;
752 for (sm = s->gsyms; sm; sm = sm->next)
753 if (sm->value <= offset && (!sym || sm->value > sym->value))
754 sym = sm;
756 if (!sym && exact) {
757 error(ERR_NONFATAL, "unable to find a suitable global symbol"
758 " for this reference");
759 return 0;
762 r = *sect->tail = nasm_malloc(sizeof(struct Reloc));
763 sect->tail = &r->next;
764 r->next = NULL;
766 r->address = sect->len;
767 r->symbol = GLOBAL_TEMP_BASE + sym->globnum;
768 r->type = type;
770 sect->nrelocs++;
772 return offset - sym->value;
775 static void elf_out(int32_t segto, const void *data, uint32_t type,
776 int32_t segment, int32_t wrt)
778 struct Section *s;
779 int32_t realbytes = type & OUT_SIZMASK;
780 int32_t addr;
781 uint8_t mydata[4], *p;
782 int i;
783 static struct symlininfo sinfo;
785 type &= OUT_TYPMASK;
788 * handle absolute-assembly (structure definitions)
790 if (segto == NO_SEG) {
791 if (type != OUT_RESERVE)
792 error(ERR_NONFATAL, "attempt to assemble code in [ABSOLUTE]"
793 " space");
794 return;
797 s = NULL;
798 for (i = 0; i < nsects; i++)
799 if (segto == sects[i]->index) {
800 s = sects[i];
801 break;
803 if (!s) {
804 int tempint; /* ignored */
805 if (segto != elf_section_names(".text", 2, &tempint))
806 error(ERR_PANIC, "strange segment conditions in ELF driver");
807 else {
808 s = sects[nsects - 1];
809 i = nsects - 1;
813 /* again some stabs debugging stuff */
814 if (of_elf32.current_dfmt) {
815 sinfo.offset = s->len;
816 sinfo.section = i;
817 sinfo.name = s->name;
818 of_elf32.current_dfmt->debug_output(TY_STABSSYMLIN, &sinfo);
820 /* end of debugging stuff */
822 if (s->type == SHT_NOBITS && type != OUT_RESERVE) {
823 error(ERR_WARNING, "attempt to initialize memory in"
824 " BSS section `%s': ignored", s->name);
825 if (type == OUT_REL2ADR)
826 realbytes = 2;
827 else if (type == OUT_REL4ADR)
828 realbytes = 4;
829 s->len += realbytes;
830 return;
833 if (type == OUT_RESERVE) {
834 if (s->type == SHT_PROGBITS) {
835 error(ERR_WARNING, "uninitialized space declared in"
836 " non-BSS section `%s': zeroing", s->name);
837 elf_sect_write(s, NULL, realbytes);
838 } else
839 s->len += realbytes;
840 } else if (type == OUT_RAWDATA) {
841 if (segment != NO_SEG)
842 error(ERR_PANIC, "OUT_RAWDATA with other than NO_SEG");
843 elf_sect_write(s, data, realbytes);
844 } else if (type == OUT_ADDRESS) {
845 bool gnu16 = false;
846 addr = *(int32_t *)data;
847 if (segment != NO_SEG) {
848 if (segment % 2) {
849 error(ERR_NONFATAL, "ELF format does not support"
850 " segment base references");
851 } else {
852 if (wrt == NO_SEG) {
853 if (realbytes == 2) {
854 gnu16 = true;
855 elf_add_reloc(s, segment, R_386_16);
856 } else {
857 elf_add_reloc(s, segment, R_386_32);
859 } else if (wrt == elf_gotpc_sect + 1) {
861 * The user will supply GOT relative to $$. ELF
862 * will let us have GOT relative to $. So we
863 * need to fix up the data item by $-$$.
865 addr += s->len;
866 elf_add_reloc(s, segment, R_386_GOTPC);
867 } else if (wrt == elf_gotoff_sect + 1) {
868 elf_add_reloc(s, segment, R_386_GOTOFF);
869 } else if (wrt == elf_got_sect + 1) {
870 addr = elf_add_gsym_reloc(s, segment, addr,
871 R_386_GOT32, true);
872 } else if (wrt == elf_sym_sect + 1) {
873 if (realbytes == 2) {
874 gnu16 = true;
875 addr = elf_add_gsym_reloc(s, segment, addr,
876 R_386_16, false);
877 } else {
878 addr = elf_add_gsym_reloc(s, segment, addr,
879 R_386_32, false);
881 } else if (wrt == elf_plt_sect + 1) {
882 error(ERR_NONFATAL, "ELF format cannot produce non-PC-"
883 "relative PLT references");
884 } else {
885 error(ERR_NONFATAL, "ELF format does not support this"
886 " use of WRT");
887 wrt = NO_SEG; /* we can at least _try_ to continue */
891 p = mydata;
892 if (gnu16) {
893 error(ERR_WARNING | ERR_WARN_GNUELF,
894 "16-bit relocations in ELF is a GNU extension");
895 WRITESHORT(p, addr);
896 } else {
897 if (realbytes != 4 && segment != NO_SEG) {
898 error(ERR_NONFATAL,
899 "Unsupported non-32-bit ELF relocation");
901 WRITELONG(p, addr);
903 elf_sect_write(s, mydata, realbytes);
904 } else if (type == OUT_REL2ADR) {
905 if (segment == segto)
906 error(ERR_PANIC, "intra-segment OUT_REL2ADR");
907 if (segment != NO_SEG && segment % 2) {
908 error(ERR_NONFATAL, "ELF format does not support"
909 " segment base references");
910 } else {
911 if (wrt == NO_SEG) {
912 error(ERR_WARNING | ERR_WARN_GNUELF,
913 "16-bit relocations in ELF is a GNU extension");
914 elf_add_reloc(s, segment, R_386_PC16);
915 } else {
916 error(ERR_NONFATAL,
917 "Unsupported non-32-bit ELF relocation");
920 p = mydata;
921 WRITESHORT(p, *(int32_t *)data - realbytes);
922 elf_sect_write(s, mydata, 2L);
923 } else if (type == OUT_REL4ADR) {
924 if (segment == segto)
925 error(ERR_PANIC, "intra-segment OUT_REL4ADR");
926 if (segment != NO_SEG && segment % 2) {
927 error(ERR_NONFATAL, "ELF format does not support"
928 " segment base references");
929 } else {
930 if (wrt == NO_SEG) {
931 elf_add_reloc(s, segment, R_386_PC32);
932 } else if (wrt == elf_plt_sect + 1) {
933 elf_add_reloc(s, segment, R_386_PLT32);
934 } else if (wrt == elf_gotpc_sect + 1 ||
935 wrt == elf_gotoff_sect + 1 ||
936 wrt == elf_got_sect + 1) {
937 error(ERR_NONFATAL, "ELF format cannot produce PC-"
938 "relative GOT references");
939 } else {
940 error(ERR_NONFATAL, "ELF format does not support this"
941 " use of WRT");
942 wrt = NO_SEG; /* we can at least _try_ to continue */
945 p = mydata;
946 WRITELONG(p, *(int32_t *)data - realbytes);
947 elf_sect_write(s, mydata, 4L);
951 static void elf_write(void)
953 int nsections, align;
954 int scount;
955 char *p;
956 int commlen;
957 char comment[64];
958 int i;
960 struct SAA *symtab;
961 int32_t symtablen, symtablocal;
964 * Work out how many sections we will have. We have SHN_UNDEF,
965 * then the flexible user sections, then the four fixed
966 * sections `.comment', `.shstrtab', `.symtab' and `.strtab',
967 * then optionally relocation sections for the user sections.
969 if (of_elf32.current_dfmt == &df_stabs)
970 nsections = 8;
971 else
972 nsections = 5; /* SHN_UNDEF and the fixed ones */
974 add_sectname("", ".comment");
975 add_sectname("", ".shstrtab");
976 add_sectname("", ".symtab");
977 add_sectname("", ".strtab");
978 for (i = 0; i < nsects; i++) {
979 nsections++; /* for the section itself */
980 if (sects[i]->head) {
981 nsections++; /* for its relocations */
982 add_sectname(".rel", sects[i]->name);
986 if (of_elf32.current_dfmt == &df_stabs) {
987 /* in case the debug information is wanted, just add these three sections... */
988 add_sectname("", ".stab");
989 add_sectname("", ".stabstr");
990 add_sectname(".rel", ".stab");
994 * Do the comment.
996 *comment = '\0';
997 commlen =
998 2 + sprintf(comment + 1, "The Netwide Assembler %s", NASM_VER);
1001 * Output the ELF header.
1003 fwrite("\177ELF\1\1\1\0\0\0\0\0\0\0\0\0", 16, 1, elffp);
1004 fwriteint16_t(1, elffp); /* ET_REL relocatable file */
1005 fwriteint16_t(3, elffp); /* EM_386 processor ID */
1006 fwriteint32_t(1L, elffp); /* EV_CURRENT file format version */
1007 fwriteint32_t(0L, elffp); /* no entry point */
1008 fwriteint32_t(0L, elffp); /* no program header table */
1009 fwriteint32_t(0x40L, elffp); /* section headers straight after
1010 * ELF header plus alignment */
1011 fwriteint32_t(0L, elffp); /* 386 defines no special flags */
1012 fwriteint16_t(0x34, elffp); /* size of ELF header */
1013 fwriteint16_t(0, elffp); /* no program header table, again */
1014 fwriteint16_t(0, elffp); /* still no program header table */
1015 fwriteint16_t(0x28, elffp); /* size of section header */
1016 fwriteint16_t(nsections, elffp); /* number of sections */
1017 fwriteint16_t(nsects + 2, elffp); /* string table section index for
1018 * section header table */
1019 fwriteint32_t(0L, elffp); /* align to 0x40 bytes */
1020 fwriteint32_t(0L, elffp);
1021 fwriteint32_t(0L, elffp);
1024 * Build the symbol table and relocation tables.
1026 symtab = elf_build_symtab(&symtablen, &symtablocal);
1027 for (i = 0; i < nsects; i++)
1028 if (sects[i]->head)
1029 sects[i]->rel = elf_build_reltab(&sects[i]->rellen,
1030 sects[i]->head);
1033 * Now output the section header table.
1036 elf_foffs = 0x40 + 0x28 * nsections;
1037 align = ((elf_foffs + SEG_ALIGN_1) & ~SEG_ALIGN_1) - elf_foffs;
1038 elf_foffs += align;
1039 elf_nsect = 0;
1040 elf_sects = nasm_malloc(sizeof(*elf_sects) * (2 * nsects + 10));
1042 elf_section_header(0, 0, 0, NULL, false, 0L, 0, 0, 0, 0); /* SHN_UNDEF */
1043 scount = 1; /* needed for the stabs debugging to track the symtable section */
1044 p = shstrtab + 1;
1045 for (i = 0; i < nsects; i++) {
1046 elf_section_header(p - shstrtab, sects[i]->type, sects[i]->flags,
1047 (sects[i]->type == SHT_PROGBITS ?
1048 sects[i]->data : NULL), true,
1049 sects[i]->len, 0, 0, sects[i]->align, 0);
1050 p += strlen(p) + 1;
1051 scount++; /* dito */
1053 elf_section_header(p - shstrtab, 1, 0, comment, false, (int32_t)commlen, 0, 0, 1, 0); /* .comment */
1054 scount++; /* dito */
1055 p += strlen(p) + 1;
1056 elf_section_header(p - shstrtab, 3, 0, shstrtab, false, (int32_t)shstrtablen, 0, 0, 1, 0); /* .shstrtab */
1057 scount++; /* dito */
1058 p += strlen(p) + 1;
1059 elf_section_header(p - shstrtab, 2, 0, symtab, true, symtablen, nsects + 4, symtablocal, 4, 16); /* .symtab */
1060 symtabsection = scount; /* now we got the symtab section index in the ELF file */
1061 p += strlen(p) + 1;
1062 elf_section_header(p - shstrtab, 3, 0, strs, true, strslen, 0, 0, 1, 0); /* .strtab */
1063 for (i = 0; i < nsects; i++)
1064 if (sects[i]->head) {
1065 p += strlen(p) + 1;
1066 elf_section_header(p - shstrtab, 9, 0, sects[i]->rel, true,
1067 sects[i]->rellen, nsects + 3, i + 1, 4, 8);
1069 if (of_elf32.current_dfmt == &df_stabs) {
1070 /* for debugging information, create the last three sections
1071 which are the .stab , .stabstr and .rel.stab sections respectively */
1073 /* this function call creates the stab sections in memory */
1074 stabs32_generate();
1076 if ((stabbuf) && (stabstrbuf) && (stabrelbuf)) {
1077 p += strlen(p) + 1;
1078 elf_section_header(p - shstrtab, 1, 0, stabbuf, false, stablen,
1079 nsections - 2, 0, 4, 12);
1081 p += strlen(p) + 1;
1082 elf_section_header(p - shstrtab, 3, 0, stabstrbuf, false,
1083 stabstrlen, 0, 0, 4, 0);
1085 p += strlen(p) + 1;
1086 /* link -> symtable info -> section to refer to */
1087 elf_section_header(p - shstrtab, 9, 0, stabrelbuf, false,
1088 stabrellen, symtabsection, nsections - 3, 4,
1092 fwrite(align_str, align, 1, elffp);
1095 * Now output the sections.
1097 elf_write_sections();
1099 nasm_free(elf_sects);
1100 saa_free(symtab);
1103 static struct SAA *elf_build_symtab(int32_t *len, int32_t *local)
1105 struct SAA *s = saa_init(1L);
1106 struct Symbol *sym;
1107 uint8_t entry[16], *p;
1108 int i;
1110 *len = *local = 0;
1113 * First, an all-zeros entry, required by the ELF spec.
1115 saa_wbytes(s, NULL, 16L); /* null symbol table entry */
1116 *len += 16;
1117 (*local)++;
1120 * Next, an entry for the file name.
1122 p = entry;
1123 WRITELONG(p, 1); /* we know it's 1st entry in strtab */
1124 WRITELONG(p, 0); /* no value */
1125 WRITELONG(p, 0); /* no size either */
1126 WRITESHORT(p, STT_FILE); /* type FILE */
1127 WRITESHORT(p, SHN_ABS);
1128 saa_wbytes(s, entry, 16L);
1129 *len += 16;
1130 (*local)++;
1133 * Now some standard symbols defining the segments, for relocation
1134 * purposes.
1136 for (i = 1; i <= nsects; i++) {
1137 p = entry;
1138 WRITELONG(p, 0); /* no symbol name */
1139 WRITELONG(p, 0); /* offset zero */
1140 WRITELONG(p, 0); /* size zero */
1141 WRITESHORT(p, STT_SECTION); /* type, binding, and visibility */
1142 WRITESHORT(p, i); /* section id */
1143 saa_wbytes(s, entry, 16L);
1144 *len += 16;
1145 (*local)++;
1149 * Now the other local symbols.
1151 saa_rewind(syms);
1152 while ((sym = saa_rstruct(syms))) {
1153 if (sym->type & SYM_GLOBAL)
1154 continue;
1155 p = entry;
1156 WRITELONG(p, sym->strpos);
1157 WRITELONG(p, sym->value);
1158 WRITELONG(p, sym->size);
1159 WRITECHAR(p, sym->type); /* type and binding */
1160 WRITECHAR(p, sym->other); /* visibility */
1161 WRITESHORT(p, sym->section);
1162 saa_wbytes(s, entry, 16L);
1163 *len += 16;
1164 (*local)++;
1168 * Now the global symbols.
1170 saa_rewind(syms);
1171 while ((sym = saa_rstruct(syms))) {
1172 if (!(sym->type & SYM_GLOBAL))
1173 continue;
1174 p = entry;
1175 WRITELONG(p, sym->strpos);
1176 WRITELONG(p, sym->value);
1177 WRITELONG(p, sym->size);
1178 WRITECHAR(p, sym->type); /* type and binding */
1179 WRITECHAR(p, sym->other); /* visibility */
1180 WRITESHORT(p, sym->section);
1181 saa_wbytes(s, entry, 16L);
1182 *len += 16;
1185 return s;
1188 static struct SAA *elf_build_reltab(int32_t *len, struct Reloc *r)
1190 struct SAA *s;
1191 uint8_t *p, entry[8];
1193 if (!r)
1194 return NULL;
1196 s = saa_init(1L);
1197 *len = 0;
1199 while (r) {
1200 int32_t sym = r->symbol;
1202 if (sym >= GLOBAL_TEMP_BASE)
1203 sym += -GLOBAL_TEMP_BASE + (nsects + 2) + nlocals;
1205 p = entry;
1206 WRITELONG(p, r->address);
1207 WRITELONG(p, (sym << 8) + r->type);
1208 saa_wbytes(s, entry, 8L);
1209 *len += 8;
1211 r = r->next;
1214 return s;
1217 static void elf_section_header(int name, int type, int flags,
1218 void *data, bool is_saa, int32_t datalen,
1219 int link, int info, int align, int eltsize)
1221 elf_sects[elf_nsect].data = data;
1222 elf_sects[elf_nsect].len = datalen;
1223 elf_sects[elf_nsect].is_saa = is_saa;
1224 elf_nsect++;
1226 fwriteint32_t((int32_t)name, elffp);
1227 fwriteint32_t((int32_t)type, elffp);
1228 fwriteint32_t((int32_t)flags, elffp);
1229 fwriteint32_t(0L, elffp); /* no address, ever, in object files */
1230 fwriteint32_t(type == 0 ? 0L : elf_foffs, elffp);
1231 fwriteint32_t(datalen, elffp);
1232 if (data)
1233 elf_foffs += (datalen + SEG_ALIGN_1) & ~SEG_ALIGN_1;
1234 fwriteint32_t((int32_t)link, elffp);
1235 fwriteint32_t((int32_t)info, elffp);
1236 fwriteint32_t((int32_t)align, elffp);
1237 fwriteint32_t((int32_t)eltsize, elffp);
1240 static void elf_write_sections(void)
1242 int i;
1243 for (i = 0; i < elf_nsect; i++)
1244 if (elf_sects[i].data) {
1245 int32_t len = elf_sects[i].len;
1246 int32_t reallen = (len + SEG_ALIGN_1) & ~SEG_ALIGN_1;
1247 int32_t align = reallen - len;
1248 if (elf_sects[i].is_saa)
1249 saa_fpwrite(elf_sects[i].data, elffp);
1250 else
1251 fwrite(elf_sects[i].data, len, 1, elffp);
1252 fwrite(align_str, align, 1, elffp);
1256 static void elf_sect_write(struct Section *sect,
1257 const uint8_t *data, uint32_t len)
1259 saa_wbytes(sect->data, data, len);
1260 sect->len += len;
1263 static int32_t elf_segbase(int32_t segment)
1265 return segment;
1268 static int elf_directive(char *directive, char *value, int pass)
1270 (void)directive;
1271 (void)value;
1272 (void)pass;
1273 return 0;
1276 static void elf_filename(char *inname, char *outname, efunc error)
1278 strcpy(elf_module, inname);
1279 standard_extension(inname, outname, ".o", error);
1282 static const char *elf_stdmac[] = {
1283 "%define __SECT__ [section .text]",
1284 "%macro __NASM_CDecl__ 1",
1285 "%define $_%1 $%1",
1286 "%endmacro",
1287 NULL
1289 static int elf_set_info(enum geninfo type, char **val)
1291 (void)type;
1292 (void)val;
1293 return 0;
1296 static struct dfmt df_stabs = {
1297 "ELF32 (i386) stabs debug format for Linux",
1298 "stabs",
1299 stabs32_init,
1300 stabs32_linenum,
1301 stabs32_deflabel,
1302 stabs32_directive,
1303 stabs32_typevalue,
1304 stabs32_output,
1305 stabs32_cleanup
1308 struct dfmt *elf32_debugs_arr[2] = { &df_stabs, NULL };
1310 struct ofmt of_elf32 = {
1311 "ELF32 (i386) object files (e.g. Linux)",
1312 "elf32",
1313 NULL,
1314 elf32_debugs_arr,
1315 &null_debug_form,
1316 elf_stdmac,
1317 elf_init,
1318 elf_set_info,
1319 elf_out,
1320 elf_deflabel,
1321 elf_section_names,
1322 elf_segbase,
1323 elf_directive,
1324 elf_filename,
1325 elf_cleanup
1328 struct ofmt of_elf = {
1329 "ELF (short name for ELF32) ",
1330 "elf",
1331 NULL,
1332 elf32_debugs_arr,
1333 &null_debug_form,
1334 elf_stdmac,
1335 elf_init,
1336 elf_set_info,
1337 elf_out,
1338 elf_deflabel,
1339 elf_section_names,
1340 elf_segbase,
1341 elf_directive,
1342 elf_filename,
1343 elf_cleanup
1345 /* again, the stabs debugging stuff (code) */
1347 void stabs32_init(struct ofmt *of, void *id, FILE * fp, efunc error)
1349 (void)of;
1350 (void)id;
1351 (void)fp;
1352 (void)error;
1355 void stabs32_linenum(const char *filename, int32_t linenumber, int32_t segto)
1357 (void)segto;
1359 if (!stabs_filename) {
1360 stabs_filename = (char *)nasm_malloc(strlen(filename) + 1);
1361 strcpy(stabs_filename, filename);
1362 } else {
1363 if (strcmp(stabs_filename, filename)) {
1364 /* yep, a memory leak...this program is one-shot anyway, so who cares...
1365 in fact, this leak comes in quite handy to maintain a list of files
1366 encountered so far in the symbol lines... */
1368 /* why not nasm_free(stabs_filename); we're done with the old one */
1370 stabs_filename = (char *)nasm_malloc(strlen(filename) + 1);
1371 strcpy(stabs_filename, filename);
1374 stabs_immcall = 1;
1375 currentline = linenumber;
1378 void stabs32_deflabel(char *name, int32_t segment, int32_t offset, int is_global,
1379 char *special)
1381 (void)name;
1382 (void)segment;
1383 (void)offset;
1384 (void)is_global;
1385 (void)special;
1388 void stabs32_directive(const char *directive, const char *params)
1390 (void)directive;
1391 (void)params;
1394 void stabs32_typevalue(int32_t type)
1396 int32_t stype, ssize;
1397 switch (TYM_TYPE(type)) {
1398 case TY_LABEL:
1399 ssize = 0;
1400 stype = STT_NOTYPE;
1401 break;
1402 case TY_BYTE:
1403 ssize = 1;
1404 stype = STT_OBJECT;
1405 break;
1406 case TY_WORD:
1407 ssize = 2;
1408 stype = STT_OBJECT;
1409 break;
1410 case TY_DWORD:
1411 ssize = 4;
1412 stype = STT_OBJECT;
1413 break;
1414 case TY_FLOAT:
1415 ssize = 4;
1416 stype = STT_OBJECT;
1417 break;
1418 case TY_QWORD:
1419 ssize = 8;
1420 stype = STT_OBJECT;
1421 break;
1422 case TY_TBYTE:
1423 ssize = 10;
1424 stype = STT_OBJECT;
1425 break;
1426 case TY_OWORD:
1427 ssize = 8;
1428 stype = STT_OBJECT;
1429 break;
1430 case TY_COMMON:
1431 ssize = 0;
1432 stype = STT_COMMON;
1433 break;
1434 case TY_SEG:
1435 ssize = 0;
1436 stype = STT_SECTION;
1437 break;
1438 case TY_EXTERN:
1439 ssize = 0;
1440 stype = STT_NOTYPE;
1441 break;
1442 case TY_EQU:
1443 ssize = 0;
1444 stype = STT_NOTYPE;
1445 break;
1446 default:
1447 ssize = 0;
1448 stype = STT_NOTYPE;
1449 break;
1451 if (stype == STT_OBJECT && !lastsym->type) {
1452 lastsym->size = ssize;
1453 lastsym->type = stype;
1457 void stabs32_output(int type, void *param)
1459 struct symlininfo *s;
1460 struct linelist *el;
1461 if (type == TY_STABSSYMLIN) {
1462 if (stabs_immcall) {
1463 s = (struct symlininfo *)param;
1464 if (!(sects[s->section]->flags & SHF_EXECINSTR))
1465 return; /* we are only interested in the text stuff */
1466 numlinestabs++;
1467 el = (struct linelist *)nasm_malloc(sizeof(struct linelist));
1468 el->info.offset = s->offset;
1469 el->info.section = s->section;
1470 el->info.name = s->name;
1471 el->line = currentline;
1472 el->filename = stabs_filename;
1473 el->next = 0;
1474 if (stabslines) {
1475 stabslines->last->next = el;
1476 stabslines->last = el;
1477 } else {
1478 stabslines = el;
1479 stabslines->last = el;
1483 stabs_immcall = 0;
1486 #define WRITE_STAB(p,n_strx,n_type,n_other,n_desc,n_value) \
1487 do {\
1488 WRITELONG(p,n_strx); \
1489 WRITECHAR(p,n_type); \
1490 WRITECHAR(p,n_other); \
1491 WRITESHORT(p,n_desc); \
1492 WRITELONG(p,n_value); \
1493 } while (0)
1495 /* for creating the .stab , .stabstr and .rel.stab sections in memory */
1497 void stabs32_generate(void)
1499 int i, numfiles, strsize, numstabs = 0, currfile, mainfileindex;
1500 uint8_t *sbuf, *ssbuf, *rbuf, *sptr, *rptr;
1501 char **allfiles;
1502 int *fileidx;
1504 struct linelist *ptr;
1506 ptr = stabslines;
1508 allfiles = (char **)nasm_malloc(numlinestabs * sizeof(char *));
1509 for (i = 0; i < numlinestabs; i++)
1510 allfiles[i] = 0;
1511 numfiles = 0;
1512 while (ptr) {
1513 if (numfiles == 0) {
1514 allfiles[0] = ptr->filename;
1515 numfiles++;
1516 } else {
1517 for (i = 0; i < numfiles; i++) {
1518 if (!strcmp(allfiles[i], ptr->filename))
1519 break;
1521 if (i >= numfiles) {
1522 allfiles[i] = ptr->filename;
1523 numfiles++;
1526 ptr = ptr->next;
1528 strsize = 1;
1529 fileidx = (int *)nasm_malloc(numfiles * sizeof(int));
1530 for (i = 0; i < numfiles; i++) {
1531 fileidx[i] = strsize;
1532 strsize += strlen(allfiles[i]) + 1;
1534 mainfileindex = 0;
1535 for (i = 0; i < numfiles; i++) {
1536 if (!strcmp(allfiles[i], elf_module)) {
1537 mainfileindex = i;
1538 break;
1542 /* worst case size of the stab buffer would be:
1543 the sourcefiles changes each line, which would mean 1 SOL, 1 SYMLIN per line
1545 sbuf =
1546 (uint8_t *)nasm_malloc((numlinestabs * 2 + 3) *
1547 sizeof(struct stabentry));
1549 ssbuf = (uint8_t *)nasm_malloc(strsize);
1551 rbuf = (uint8_t *)nasm_malloc(numlinestabs * 8 * (2 + 3));
1552 rptr = rbuf;
1554 for (i = 0; i < numfiles; i++) {
1555 strcpy((char *)ssbuf + fileidx[i], allfiles[i]);
1557 ssbuf[0] = 0;
1559 stabstrlen = strsize; /* set global variable for length of stab strings */
1561 sptr = sbuf;
1562 ptr = stabslines;
1563 numstabs = 0;
1565 if (ptr) {
1566 /* this is the first stab, its strx points to the filename of the
1567 the source-file, the n_desc field should be set to the number
1568 of remaining stabs
1570 WRITE_STAB(sptr, fileidx[0], 0, 0, 0, strlen(allfiles[0] + 12));
1572 /* this is the stab for the main source file */
1573 WRITE_STAB(sptr, fileidx[mainfileindex], N_SO, 0, 0, 0);
1575 /* relocation table entry */
1577 /* Since the symbol table has two entries before */
1578 /* the section symbols, the index in the info.section */
1579 /* member must be adjusted by adding 2 */
1581 WRITELONG(rptr, (sptr - sbuf) - 4);
1582 WRITELONG(rptr, ((ptr->info.section + 2) << 8) | R_386_32);
1584 numstabs++;
1585 currfile = mainfileindex;
1588 while (ptr) {
1589 if (strcmp(allfiles[currfile], ptr->filename)) {
1590 /* oops file has changed... */
1591 for (i = 0; i < numfiles; i++)
1592 if (!strcmp(allfiles[i], ptr->filename))
1593 break;
1594 currfile = i;
1595 WRITE_STAB(sptr, fileidx[currfile], N_SOL, 0, 0,
1596 ptr->info.offset);
1597 numstabs++;
1599 /* relocation table entry */
1600 WRITELONG(rptr, (sptr - sbuf) - 4);
1601 WRITELONG(rptr, ((ptr->info.section + 2) << 8) | R_386_32);
1604 WRITE_STAB(sptr, 0, N_SLINE, 0, ptr->line, ptr->info.offset);
1605 numstabs++;
1607 /* relocation table entry */
1609 WRITELONG(rptr, (sptr - sbuf) - 4);
1610 WRITELONG(rptr, ((ptr->info.section + 2) << 8) | R_386_32);
1612 ptr = ptr->next;
1616 ((struct stabentry *)sbuf)->n_desc = numstabs;
1618 nasm_free(allfiles);
1619 nasm_free(fileidx);
1621 stablen = (sptr - sbuf);
1622 stabrellen = (rptr - rbuf);
1623 stabrelbuf = rbuf;
1624 stabbuf = sbuf;
1625 stabstrbuf = ssbuf;
1628 void stabs32_cleanup(void)
1630 struct linelist *ptr, *del;
1631 if (!stabslines)
1632 return;
1633 ptr = stabslines;
1634 while (ptr) {
1635 del = ptr;
1636 ptr = ptr->next;
1637 nasm_free(del);
1639 if (stabbuf)
1640 nasm_free(stabbuf);
1641 if (stabrelbuf)
1642 nasm_free(stabrelbuf);
1643 if (stabstrbuf)
1644 nasm_free(stabstrbuf);
1647 #endif /* OF_ELF */